Science.gov

Sample records for ac electric drive

  1. A PWM transistor inverter for an ac electric vehicle drive

    NASA Technical Reports Server (NTRS)

    Slicker, J. M.

    1981-01-01

    A prototype system consisting of closely integrated motor, inverter, and transaxle has been built in order to demonstrate the feasibility of a three-phase ac transistorized inverter for electric vehicle applications. The microprocessor-controlled inverter employs monolithic power transistors to drive an oil-cooled, three-phase induction traction motor at a peak output power of 30 kW from a 144 V battery pack. Transistor safe switching requirements are discussed, and a circuit is presented for recovering trapped snubber inductor energy at transistor turn-off.

  2. Progress on advanced dc and ac induction drives for electric vehicles

    NASA Technical Reports Server (NTRS)

    Schwartz, H. J.

    1982-01-01

    Progress is reported in the development of complete electric vehicle propulsion systems, and the results of tests on the Road Load Simulator of two such systems representative of advanced dc and ac drive technology are presented. One is the system used in the DOE's ETV-1 integrated test vehicle which consists of a shunt wound dc traction motor under microprocessor control using a transistorized controller. The motor drives the vehicle through a fixed ratio transmission. The second system uses an ac induction motor controlled by transistorized pulse width modulated inverter which drives through a two speed automatically shifted transmission. The inverter and transmission both operate under the control of a microprocessor. The characteristics of these systems are also compared with the propulsion system technology available in vehicles being manufactured at the inception of the DOE program and with an advanced, highly integrated propulsion system upon which technology development was recently initiated.

  3. Evaluation of semiconductor devices for Electric and Hybrid Vehicle (EHV) ac-drive applications, volume 1

    NASA Technical Reports Server (NTRS)

    Lee, F. C.; Chen, D. Y.; Jovanovic, M.; Hopkins, D. C.

    1985-01-01

    The results of evaluation of power semiconductor devices for electric hybrid vehicle ac drive applications are summarized. Three types of power devices are evaluated in the effort: high power bipolar or Darlington transistors, power MOSFETs, and asymmetric silicon control rectifiers (ASCR). The Bipolar transistors, including discrete device and Darlington devices, range from 100 A to 400 A and from 400 V to 900 V. These devices are currently used as key switching elements inverters for ac motor drive applications. Power MOSFETs, on the other hand, are much smaller in current rating. For the 400 V device, the current rating is limited to 25 A. For the main drive of an electric vehicle, device paralleling is normally needed to achieve practical power level. For other electric vehicle (EV) related applications such as battery charger circuit, however, MOSFET is advantageous to other devices because of drive circuit simplicity and high frequency capability. Asymmetrical SCR is basically a SCR device and needs commutation circuit for turn off. However, the device poses several advantages, i.e., low conduction drop and low cost.

  4. Frequency Domain Analysis of Beat-Less Control Method for Converter-Inverter Driving Systems Applied to AC Electric Cars

    NASA Astrophysics Data System (ADS)

    Kimura, Akira

    In inverter-converter driving systems for AC electric cars, the DC input voltage of an inverter contains a ripple component with a frequency that is twice as high as the line voltage frequency, because of a single-phase converter. The ripple component of the inverter input voltage causes pulsations on torques and currents of driving motors. To decrease the pulsations, a beat-less control method, which modifies a slip frequency depending on the ripple component, is applied to the inverter control. In the present paper, the beat-less control method was analyzed in the frequency domain. In the first step of the analysis, transfer functions, which revealed the relationship among the ripple component of the inverter input voltage, the slip frequency, the motor torque pulsation and the current pulsation, were derived with a synchronous rotating model of induction motors. An analysis model of the beat-less control method was then constructed using the transfer functions. The optimal setting of the control method was obtained according to the analysis model. The transfer functions and the analysis model were verified through simulations.

  5. Electric versus hydraulic drives

    SciTech Connect

    Not Available

    1983-01-01

    This volume records the proceedings of a conference organised by the Engineering Manufacturing Industries Division of the Institution of Mechanical Engineers. Topics considered include high performance position control - a review of the current state of developments; hydrostatic drives - present and future; electric drives - present and future trends; electrical and hydraulic drives for heavy industrial robots; the development of an electro-mechanical tilt system for the advanced passenger train; industrial hydraulic ring mains - effective or efficient. the comparison of performance of servo feed-drive systems; overhead crane drives; the future of d.c. servodrives; the choice of actuator for military systems; linear electro-hydraulic actuators; and actuation for industrial robots.

  6. Electric vehicles: Driving range

    NASA Astrophysics Data System (ADS)

    Kempton, Willett

    2016-09-01

    For uptake of electric vehicles to increase, consumers' driving-range needs must be fulfilled. Analysis of the driving patterns of personal vehicles in the US now shows that today's electric vehicles can meet all travel needs on almost 90% of days from a single overnight charge.

  7. ac propulsion system for an electric vehicle

    NASA Technical Reports Server (NTRS)

    Geppert, S.

    1980-01-01

    It is pointed out that dc drives will be the logical choice for current production electric vehicles (EV). However, by the mid-80's, there is a good chance that the price and reliability of suitable high-power semiconductors will allow for a competitive ac system. The driving force behind the ac approach is the induction motor, which has specific advantages relative to a dc shunt or series traction motor. These advantages would be an important factor in the case of a vehicle for which low maintenance characteristics are of primary importance. A description of an EV ac propulsion system is provided, taking into account the logic controller, the inverter, the motor, and a two-speed transmission-differential-axle assembly. The main barrier to the employment of the considered propulsion system in EV is not any technical problem, but inverter transistor cost.

  8. Electric vehicle drive train with contactor protection

    DOEpatents

    Konrad, C.E.; Benson, R.A.

    1994-11-29

    A drive train for an electric vehicle includes a traction battery, a power drive circuit, a main contactor for connecting and disconnecting the traction battery and the power drive circuit, a voltage detector across contacts of the main contactor, and a controller for controlling the main contactor to prevent movement of its contacts to the closed position when the voltage across the contacts exceeds a predetermined threshold, to thereby protect the contacts of the contactor. The power drive circuit includes an electric traction motor and a DC-to-AC inverter with a capacitive input filter. The controller also inhibits the power drive circuit from driving the motor and thereby discharging the input capacitor if the contacts are inadvertently opened during motoring. A precharging contactor is controlled to charge the input filter capacitor prior to closing the main contactor to further protect the contacts of the main contactor. 3 figures.

  9. Electric vehicle drive train with contactor protection

    DOEpatents

    Konrad, Charles E.; Benson, Ralph A.

    1994-01-01

    A drive train for an electric vehicle includes a traction battery, a power drive circuit, a main contactor for connecting and disconnecting the traction battery and the power drive circuit, a voltage detector across contacts of the main contactor, and a controller for controlling the main contactor to prevent movement of its contacts to the closed position when the voltage across the contacts exceeds a predetermined threshold, to thereby protect the contacts of the contactor. The power drive circuit includes an electric traction motor and a DC-to-AC inverter with a capacitive input filter. The controller also inhibits the power drive circuit from driving the motor and thereby discharging the input capacitor if the contacts are inadvertently opened during motoring. A precharging contactor is controlled to charge the input filter capacitor prior to closing the main contactor to further protect the contacts of the main contactor.

  10. Electric vehicle drive train components

    SciTech Connect

    Silver, F.

    1994-12-31

    Power Control Systems has developed a family of electric vehicle drive systems that range from 65 horsepower through 300 horse power. These propulsion systems support vehicle applications ranging from light cars and pickups to buses and trucks weighing as much as 40,000 lbs (18,400 kg). These robust systems are designed specifically for automotive applications including safety, electromagnetic emissions, and environment ruggedness. Dolphin Drive Systems are very flexible. Their inverter controllers are programmable and can be provided as stand alone components matched to customer specified motors. A selection of pre-calibrated systems including motor and inverter/controller can be provided. Accessory tools are also available for customer self programming. Dolphin Drive Systems provide precision control of AC induction motors providing excellent torque-speed performance usually eliminating the need for multistage transmissions. In addition, they are very efficient over a wide speed/torque range. This provides for excellent power management over a variety of continuous speed and stop and go applications.

  11. Electric vehicle drive systems

    NASA Astrophysics Data System (ADS)

    Appleyard, M.

    1992-01-01

    New legislation in the State of California requires that 2% of vehicles sold there from 1998 will be 'zero-emitting'. This provides a unique market opportunity for developers of electric vehicles but substantial improvements in the technology are probably required if it is to be successfully exploited. There are around a dozen types of battery that are potentially relevant to road vehicles but, at the present, lead/acid and sodium—sulphur come closest to combining acceptable performance, life and cost. To develop an efficient, lightweight electric motor system requires up-to-date techniques of magnetics design, and the latest power-electronic and microprocessor control methods. Brushless machines, coupled with solid-state inverters, offer the most economical solution for mass production, even though their development costs are higher than for direct-current commutator machines. Fitted to a small car, even the highest energy-density batteries will only provide around 200 km average range before recharging. Therefore, some form of supplementary on-board power generation will probably be needed to secure widespread acceptance by the driving public. Engine-driven generators of quite low power can achieve useful increases in urban range but will fail to qualify as 'zero-emitting'. On the other hand, if the same function could be economically performed by a small fuel-cell using hydrogen derived from a methanol reformer, then most of the flexibility provided by conventional vehicles would be retained. The market prospects for electric cars would then be greatly enhanced and their dependence on very advanced battery technology would be reduced.

  12. AC drive system efficiency evaluation. Final report

    SciTech Connect

    Langley, R.

    1998-12-01

    Industrial and commercial facilities are continually searching for ways to reduce costs while increasing revenues. One way of accomplishing this objective is to reduce energy consumption costs. Industrial and commercial facilities, in their heavy reliance on electric motors, are by far the largest consumers of electric power. In fact, electric motors consume more than fifty percent of all generated electric energy. The use of energy efficient motors and electronic adjustable-speed drives (ASDs) can provide industries with a means for reducing energy costs. Taking advantage of available contracts with incentives for energy conservation, industries can justify the costs for retrofitting old inefficient production lines with state-of-the-art, efficient, process equipment. The use of ASDs for improving process control and increasing process efficiency has been well documented. To this point, however, there are no published research reports or technical papers presenting energy efficiency data for ASDs and ASD/motor systems at load conditions other than rated load conditions. The IEC-1800 standard does call for manufacturers to report the ASD or the ASD/motor system efficiency at rated load and base speed conditions. This report presents energy efficiency test data for two 150-hp ASD/motor combinations. Each test was conducted at multiple load torque and speed setpoints, which includes interpretations and discussions of the test results. The report presents test standards, test procedures, and test data that show how the energy efficiencies of ASD/motor system components relate. 51 figs., 13 tabs.

  13. An AC drive system for a battery driven moped

    SciTech Connect

    Nandi, S.; Saha, S.; Sharon, M.; Sundersingh, V.P.

    1995-12-31

    A petrol driven moped is converted to an electric one by replacing the petrol engine by a three phase 1.5 HR, AC squirrel cage induction motor drive system. The motor voltage rating selected is 200 V to keep the DC boost voltage level to a reasonable value.f the power source used is a high energy density, 24 V, 110 Ah, Ni-Zn battery. A modified indirect current controlled step-up chopper as well as a standard push-pull DC-DC boost converter is studied for the boost scheme. A simple three phase quasi-square wave inverter is designed along with suitable protection for driving the motor. Successful trial test of the system has been conducted at the laboratory.

  14. Promising Electric Aircraft Drive Systems

    NASA Technical Reports Server (NTRS)

    Dudley, Michael R.

    2010-01-01

    An overview of electric aircraft propulsion technology performance thresholds for key power system components is presented. A weight comparison of electric drive systems with equivalent total delivered energy is made to help identify component performance requirements, and promising research and development opportunities.

  15. Drive axle for electric vehicle

    SciTech Connect

    Travis, J.M.

    1981-06-02

    An electric powered vehicle drive axle is disclosed. The axle of the present invention comprises a ring gear; a first pinion gear for rotating the ring gear; a differential carried by the ring gear; a pair of axle shafts driven by the differential for rotatably driving a pair of drive wheels; the device supported and enclosed by a housing. A second pinion gear is employed which rotatably engages the ring gear. A first electric motor rotatably connected to the first pinion gear is connected to a power source for rotatably driving the vehicle. A second electric motor/generator is connected to the second pinion gear and electrically connected to the power source. The second electric motor/generator selectively powers the differential or derives power from the differential to recharge the power source as dictated by the power needs of the electric vehicle. A plurality of bevel gears are deployed along the length of the axles. Each bevel gear is rotatably connected to a pair of opposed bevel gears, each opposed bevel gear is rotatably connected to an electric motor/generator. By selectively and electrically causing the plurality of motors/generators to either power the axle or be powered by the axle optimum efficiency and recharging of the battery over a range of vehicle operating conditions is obtained.

  16. Measurement of coupling resonance driving terms with the AC dipole

    SciTech Connect

    Miyamoto, R.

    2010-10-01

    Resonance driving terms for linear coupled betatron motion in a synchrotron ring can be determined from corresponding spectral lines of an excited coherent beam motion. An AC dipole is one of instruments to excite such a motion. When a coherent motion is excited with an AC dipole, measured Courant-Snyder parameters and betatron phase advance have apparent modulations, as if there is an additional quadrupole field at the location of the AC dipole. Hence, measurements of these parameters using the AC dipole require a proper interpretation of observed quantities. The situation is similar in measurements of resonance driving terms using the AC dipole. In this note, we derive an expression of coupled betatron motion excited with two AC dipoles in presence of skew quadrupole fields, discuss an impact of this quadrupole like effect of the AC dipole on a measurement of coupling resonance driving terms, and present an analytical method to determine the coupling resonance driving terms from quantities observed using the AC dipole.

  17. Alternating-Current Motor Drive for Electric Vehicles

    NASA Technical Reports Server (NTRS)

    Krauthamer, S.; Rippel, W. E.

    1982-01-01

    New electric drive controls speed of a polyphase as motor by varying frequency of inverter output. Closed-loop current-sensing circuit automatically adjusts frequency of voltage-controlled oscillator that controls inverter frequency, to limit starting and accelerating surges. Efficient inverter and ac motor would give electric vehicles extra miles per battery charge.

  18. Sequential control by speed drive for ac motor

    NASA Astrophysics Data System (ADS)

    Barsoum, Nader

    2012-11-01

    The speed drive for ac motor is widely used in the industrial field to allow direct control for the speed and torque without any feedback from the motor shaft. By using the ABB ACS800 speed drive unit, the speed and torque can be controlled using sequential control method. Sequential control is one of the application control method provided in the ABB ACS800 Drive, where a set of events or action performed in a particular order one after the other to control the speed and torque of the ac motor. It was claimed that sequential control method is using the preset seven constant speeds being provided in ABB ACS800 drive to control the speed and torque in a continuous and sequential manner. The characteristics and features of controlling the speed and torque using sequential control method can be investigated by observing the graphs and curves plotted which are obtained from the practical result. Sequential control can run either in the Direct Torque Control (DTC) or Scalar motor control mode. By using sequential control method, the ABB ACS800 drive can be programmed to run the motor automatically according to the time setting of the seven preset constant speeds. Besides, the intention of this project is to generate a new form of the experimental set up.

  19. Multilevel converters for large electric drives

    SciTech Connect

    Tolbert, L.M.; Peng, F.Z.

    1997-11-01

    Traditional two-level high frequency pulse width modulation (PWM) inverters for motor drives have several problems associated with their high frequency switching which produces common-mode voltage and high voltage change (dV/dt) rates to the motor windings. Multilevel inverters solve these problems because their devices can switch at a much lower frequency. Two different multilevel topologies are identified for use as a converter for electric drives, a cascade inverter with separate dc sources and a back-to-back diode clamped converter. The cascade inverter is a natural fit for large automotive all electric drives because of the high VA ratings possible and because it uses several levels of dc voltage sources which would be available from batteries or fuel cells. The back to back diode damped converter is ideal where a source of ac voltage is available such as a hybrid electric vehicle. Simulation and experimental results show the superiority of these two converters over PWM based drives.

  20. The ac propulsion system for an electric vehicle, phase 1

    NASA Technical Reports Server (NTRS)

    Geppert, S.

    1981-01-01

    A functional prototype of an electric vehicle ac propulsion system was built consisting of a 18.65 kW rated ac induction traction motor, pulse width modulated (PWM) transistorized inverter, two speed mechanically shifted automatic transmission, and an overall drive/vehicle controller. Design developmental steps, and test results of individual components and the complex system on an instrumented test frame are described. Computer models were developed for the inverter, motor and a representative vehicle. A preliminary reliability model and failure modes effects analysis are given.

  1. Manipulating Flames with AC Electric Fields

    NASA Astrophysics Data System (ADS)

    Bishop, Kyle

    2013-11-01

    Time-oscillating electric fields applied to plasmas present in flames create steady flows of gas capable of shaping, directing, enhancing, or even extinguishing flames. Interestingly, electric winds induced by AC electric fields can be stronger that those due to static fields of comparable magnitude. Furthermore, unlike static fields, the electric force due to AC fields is localized near the surface of the flame. Consequently, the AC response depends only on the local field at the surface of the flame - not on the position of the electrodes used to generate the field. These results suggest that oscillating electric fields can be used to manipulate and control combustion processes at a distance. To characterize and explain these effects, we investigate a simple experimental system comprising a laminar methane-air flame positioned between two parallel-plate electrodes. We quantify both the electric and hydrodynamic response of the flame as a function of frequency and magnitude of the applied field. A theoretical model shows how steady gas flows emerge from the time-averaged electrical force due to the field-induced motion of ions generated within the flame and by their disappearance by recombination. These results provide useful insights into the application of AC fields to direct combustion processes.

  2. Performance testing of the AC propulsion ELX electric vehicle

    NASA Astrophysics Data System (ADS)

    Kramer, W. E.; MacDowall, R. D.; Burke, A. F.

    1994-06-01

    Performance testing of the AC Propulsion ELX electric vehicle is described. Test data are presented and analyzed. The ELX vehicle is the first of a series of electric vehicles of interest to the California Air Resources Board. The test series is being conducted under a Cooperative Research and Development Agreement (CRADA) between the US Department of energy and the California Air Resources Board. The tests which were conducted showed that the AC Propulsion ELX electric vehicle has exceptional acceleration and range performance. When the vehicle's battery was fully charged, the vehicle can accelerate from 0 to 96 km/h in about 10 seconds. Energy consumption and range tests using consecutive FUDS and HWFET Driving cycles (the all-electric cycle) indicate that the energy economy of the AC Propulsion ELX electric vehicle with regenerative braking is 97 W(center dot)h/km, with a range of 153 km (95 miles). Computer simulations performed using the SIMPLEV Program indicate that the vehicle would have a range of 327 km (203 miles) on the all-electric cycle if the lead acid batteries were replaced with NiMH batteries having an energy density of 67 W(center dot)h/kg. Comparisons of FUDS test data with and without regenerative braking indicated that regenerative braking reduced the energy consumption of the ELX vehicle by approximately 25%.

  3. Performance testing of the AC propulsion ELX electric vehicle

    SciTech Connect

    Kramer, W.E.; MacDowall, R.D.; Burke, A.F.

    1994-06-01

    Performance testing of the AC Propulsion ELX electric vehicle is described. Test data are presented and analyzed. The ELX vehicle is the first of a series of electric vehicles of interest to the California Air Resources Board. The test series is being conducted under a Cooperative Research and Development Agreement (CRADA) between the US Department of energy and the California Air Resources Board. The tests which were conducted showed that the AC Propulsion ELX electric vehicle has exceptional acceleration and range performance. when the vehicle`s battery was fully charged, the vehicle can accelerate from 0 to 96 km/h in about 10 seconds. Energy consumption and range tests using consecutive FUDS and HWFET Driving cycles (the all-electric cycle) indicate that the energy economy of the AC Propulsion ELX electric vehicle with regenerative braking is 97 W{center_dot}h/km, with a range of 153 km (95 miles). Computer simulations performed using the SIMPLEV Program indicate that the vehicle would have a range of 327 km (203 miles) on the all-electric cycle if the lead acid batteries were replaced with NiMH batteries having an energy density of 67 W{center_dot}h/kg. Comparisons of FUDS test data with and without regenerative braking indicated that regenerative braking reduced the energy consumption of the ELX vehicle by approximately 25%.

  4. Efficient alternatives for electric drives

    SciTech Connect

    Comnes, G.A.; Barnes, R.W.

    1987-11-01

    This analysis of industrial electric motors describes the current motor stock, its energy use and operating characteristics, and innovations that could change current use patterns. It provides calculations characterizing the economic attractiveness of several existing and potential options. One attractive option given particular attention is the adjustable-speed drive which can replace throttles or valves for many pumping operations. A major conclusion is that, throughout industry, options that are both energy-saving and economically attractive appear to penetrate markets more slowly than would be socially optimal. The final section examines characteristics of industry that may contribute to slow market penetration. 29 refs., 14 figs., 14 tabs.

  5. AC propulsion system for an electric vehicle, phase 2

    NASA Technical Reports Server (NTRS)

    Slicker, J. M.

    1983-01-01

    A second-generation prototype ac propulsion system for a passenger electric vehicle was designed, fabricated, tested, installed in a modified Mercury Lynx vehicle and track tested at the Contractor's site. The system consisted of a Phase 2, 18.7 kw rated ac induction traction motor, a 192-volt, battery powered, pulse-width-modulated, transistorized inverter packaged for under rear seat installation, a 2-axis, 2-speed, automatically-shifted mechanical transaxle and a microprocessor-based powertrain/vehicle controller. A diagnostics computer to assist tuning and fault finding was fabricated. Dc-to-mechanical-system efficiency varied from 78% to 82% as axle speed/torque ranged from 159 rpm/788 nm to 65 rpm/328 nm. Track test efficiency results suggest that the ac system will be equal or superior to dc systems when driving urban cycles. Additional short-term work is being performed under a third contract phase (AC-3) to raise transaxle efficiency to predicted levels, and to improve starting and shifting characteristics. However, the long-term challenge to the system's viability remains inverter cost. A final report on the Phase 2 system, describing Phase 3 modifications, will be issued at the conclusion of AC-3.

  6. A driving scheme to reduce AC LED flicker

    NASA Astrophysics Data System (ADS)

    Tan, Jianchuan; Narendran, Nadarajah

    2013-09-01

    Light flicker is a common but unwelcome phenomenon in conventional lighting applications. In solid-state lighting, driving or dimming methods also give rise to light flicker. AC LED products in today's marketplace suffer from flicker, which stems from the arrangement of the micro-LEDs and the driving method. Research has shown that light flicker can be a health hazard to humans. Several solutions have been proposed to reduce light flicker in solid-state lighting applications; however, most have drawbacks in terms of power and other performance. This paper proposes a circuit design to reduce light flicker from AC LEDs while maintaining a normal power factor and high power efficiency. The circuit is composed of one resistive branch and one capacitive branch, and each branch drives a load which is made up of high-voltage LEDs. Percent flicker, power factor, and power efficiency were selected as three metrics, and their benchmarks were set to evaluate the performance of this circuit. Phase shift between the two branches was selected as a factor that could determine the circuit performance. The variations of percent flicker, power factor, and power efficiency as a function of phase shift were identified by theoretical analysis and were verified by experiments. The experimental results show that an optimal solution can be achieved for this circuit design at proper phase shift, where the benchmarks of the three metrics are reached.

  7. Rotating Drive for Electrical-Arc Machining

    NASA Technical Reports Server (NTRS)

    Fransen, C. D.

    1986-01-01

    Rotating drive improves quality of holes made by electrical-arc machining. Mechanism (Uni-tek, rotary head, or equivalent) attached to electrical-arc system. Drive rotates electrode as though it were mechanical drill, while an arc disintegrates metal in workpiece, thereby creating hole. Rotating electrode method often used in electric-discharge machining. NASA innovation is application of technique to electrical-arc machining.

  8. System and method for determining stator winding resistance in an AC motor using motor drives

    DOEpatents

    Lu, Bin; Habetler, Thomas G; Zhang, Pinjia

    2013-02-26

    A system and method for determining the stator winding resistance of AC motors is provided. The system includes an AC motor drive having an input connectable to an AC source and an output connectable to an input terminal of an AC motor, a pulse width modulation (PWM) converter having switches therein to control current flow and terminal voltages in the AC motor, and a control system connected to the PWM converter. The control system generates a command signal to cause the PWM converter to control an output of the AC motor drive corresponding to an input to the AC motor, selectively generates a modified command signal to cause the PWM converter to inject a DC signal into the output of the AC motor drive, and determines a stator winding resistance of the AC motor based on the DC signal of at least one of the voltage and current.

  9. Advanced ac powertrain for electric vehicles

    SciTech Connect

    Slicker, J.M.; Kalns, L.

    1985-01-01

    The design of an ac propulsion system for an electric vehicle includes a three-phase induction motor, transistorized PWM inverter/battery charger, microprocessor-based controller, and two-speed automatic transaxle. This system was built and installed in a Mercury Lynx test bed vehicle as part of a Department of Energy propulsion system development program. An integral part of the inverter is a 4-kw battery charger which utilizes one of the bridge transistors. The overall inverter strategy for this configuration is discussed. The function of the microprocessor-based controller is described. Typical test results of the total vehicle and each of its major components are given, including system efficiencies and test track performance results.

  10. Power Electronic Transformer based Three-Phase PWM AC Drives

    NASA Astrophysics Data System (ADS)

    Basu, Kaushik

    A Transformer is used to provide galvanic isolation and to connect systems at different voltage levels. It is one of the largest and most expensive component in most of the high voltage and high power systems. Its size is inversely proportional to the operating frequency. The central idea behind a power electronic transformer (PET) also known as solid state transformer is to reduce the size of the transformer by increasing the frequency. Power electronic converters are used to change the frequency of operation. Steady reduction in the cost of the semiconductor switches and the advent of advanced magnetic materials with very low loss density and high saturation flux density implies economic viability and feasibility of a design with high power density. Application of PET is in generation of power from renewable energy sources, especially wind and solar. Other important application include grid tied inverters, UPS e.t.c. In this thesis non-resonant, single stage, bi-directional PET is considered. The main objective of this converter is to generate adjustable speed and magnitude pulse width modulated (PWM) ac waveforms from an ac or dc grid with a high frequency ac link. The windings of a high frequency transformer contains leakage inductance. Any switching transition of the power electronic converter connecting the inductive load and the transformer requires commutation of leakage energy. Commutation by passive means results in power loss, decrease in the frequency of operation, distortion in the output voltage waveform, reduction in reliability and power density. In this work a source based partially loss-less commutation of leakage energy has been proposed. This technique also results in partial soft-switching. A series of converters with novel PWM strategies have been proposed to minimize the frequency of leakage inductance commutation. These PETs achieve most of the important features of modern PWM ac drives including 1) Input power factor correction, 2) Common

  11. Instabilities across the isotropic conductivity point in a nematic phenyl benzoate under AC driving.

    PubMed

    Kumar, Pramoda; Patil, Shivaram N; Hiremath, Uma S; Krishnamurthy, K S

    2007-08-01

    We characterize the sequence of bifurcations generated by ac fields in a nematic layer held between unidirectionally rubbed ITO electrodes. The material, which possesses a negative dielectric anisotropy epsilona and an inversion temperature for electrical conductivity anisotropy sigmaa, exhibits a monostable tilted alignment near TIN, the isotropic-nematic point. On cooling, an anchoring transition to the homeotropic configuration occurs close to the underlying smectic phase. The field experiments are performed for (i) negative sigmaa and homeotropic alignment, and (ii) weakly positive sigmaa and nearly homeotropic alignment. Under ac driving, the Freedericksz transition is followed by bifurcation into various patterned states. Among them are the striped states that seem to belong to the dielectric regime and localized hybrid instabilities. Very significantly, the patterned instabilities are not excited by dc fields, indicating their possible gradient flexoelectric origin. The Carr-Helfrich mechanism-based theories that take account of flexoelectric terms can explain the observed electroconvective effects only in part. PMID:17616118

  12. Electric-drive tractability indicator integrated in hybrid electric vehicle tachometer

    DOEpatents

    Tamai, Goro; Zhou, Jing; Weslati, Feisel

    2014-09-02

    An indicator, system and method of indicating electric drive usability in a hybrid electric vehicle. A tachometer is used that includes a display having an all-electric drive portion and a hybrid drive portion. The all-electric drive portion and the hybrid drive portion share a first boundary which indicates a minimum electric drive usability and a beginning of hybrid drive operation of the vehicle. The indicated level of electric drive usability is derived from at least one of a percent battery discharge, a percent maximum torque provided by the electric drive, and a percent electric drive to hybrid drive operating cost for the hybrid electric vehicle.

  13. An AC motor drive with power factor control for low cost applications

    NASA Astrophysics Data System (ADS)

    Bellar, Maria Dias

    2000-10-01

    The front-end rectifier followed by a pulse-width modulated voltage source inverter (PWM-VSI) has been a well-established power converter configuration for many industrial drives. The increasing costs on the utility usage, due to power quality regulations, and the need to improve the VA capacity of systems, e.g. off-shore drilling rigs, have increased the interest in the development of power electronic equipment with power factor control capability. Electrical motors consume a large amount of the available electrical energy, and this energy tends to increase due to the massive emerging applications of electrical motor drives in appliances and in industrial processes. Therefore, the improvement of the power factor of these low power drive systems, usually in the range from fractional horse-power (hp) to 1 hp, is of particular interest. For these power ratings, the system configuration usually comprises a single-phase to three-phase type of converter with additional circuitry for power factor control (PFC). However, this approach has an impact on the system cost and packaging. In this work, a new concept of integrating motor and power factor controls by using a single-phase to three-phase DSP based six-switch converter topology is presented. Unlike other configurations using extra switch(es) and/or extra boost inductor, in this circuit the boost action, for input current shaping, is done by the motor leakage inductances. The power factor control and inverter operation are performed by applying two modulating signals to the SPWM control logic of the converter. In this dissertation, the converter operation and a proposed control strategy will be explained. Simulation and experimental results for a DSP based induction motor drive will be provided as proof of concept. The feasibility and potential of this configuration for ac motor drive applications will be established. The impact of this scheme on the machine operation will also be discussed.

  14. Integrated Inverter For Driving Multiple Electric Machines

    DOEpatents

    Su, Gui-Jia [Knoxville, TN; Hsu, John S [Oak Ridge, TN

    2006-04-04

    An electric machine drive (50) has a plurality of inverters (50a, 50b) for controlling respective electric machines (57, 62), which may include a three-phase main traction machine (57) and two-phase accessory machines (62) in a hybrid or electric vehicle. The drive (50) has a common control section (53, 54) for controlling the plurality of inverters (50a, 50b) with only one microelectronic processor (54) for controlling the plurality of inverters (50a, 50b), only one gate driver circuit (53) for controlling conduction of semiconductor switches (S1-S10) in the plurality of inverters (50a, 50b), and also includes a common dc bus (70), a common dc bus filtering capacitor (C1) and a common dc bus voltage sensor (67). The electric machines (57, 62) may be synchronous machines, induction machines, or PM machines and may be operated in a motoring mode or a generating mode.

  15. Improved transistorized AC motor controller for battery powered urban electric passenger vehicles

    NASA Technical Reports Server (NTRS)

    Peak, S. C.

    1982-01-01

    An ac motor controller for an induction motor electric vehicle drive system was designed, fabricated, tested, evaluated, and cost analyzed. A vehicle performance analysis was done to establish the vehicle tractive effort-speed requirements. These requirements were then converted into a set of ac motor and ac controller requirements. The power inverter is a three-phase bridge using power Darlington transistors. The induction motor was optimized for use with an inverter power source. The drive system has a constant torque output to base motor speed and a constant horsepower output to maximum speed. A gear shifting transmission is not required. The ac controller was scaled from the base 20 hp (41 hp peak) at 108 volts dec to an expanded horsepower and battery voltage range. Motor reversal was accomplished by electronic reversal of the inverter phase sequence. The ac controller can also be used as a boost chopper battery charger. The drive system was tested on a dynamometer and results are presented. The current-controlled pulse width modulation control scheme yielded improved motor current waveforms. The ac controller favors a higher system voltage.

  16. Direct drive options for electric propulsion systems

    NASA Technical Reports Server (NTRS)

    Hamley, John A.

    1995-01-01

    Power processing units (PPU's) in an electric propulsion system provide many challenging integration issues. The PPU must provide power to the electric thruster while maintaining compatibility with all of the spacecraft power and data systems. Inefficiencies in the power processor produce heat, which must be radiated to the environment in order to ensure reliable operation. Although PPU efficiencies are generally greater than 0.9, heat loads are often substantial. This heat must be rejected by thermal control systems which generally have specific masses of 15-30 kg/kW. PPU's also represent a large fraction of the electric propulsion system dry mass. Simplification or elimination of power processing in a propulsion system would reduce the electric propulsion system specific mass and improve the overall reliability and performance. A direct drive system would eliminate all or some of the power supplies required to operate a thruster by directly connecting the various thruster loads to the solar array. The development of concentrator solar arrays has enabled power bus voltages in excess of 300 V which is high enough for direct drive applications for Hall thrusters such as the Stationary Plasma Thruster (SPT). The option of solar array direct drive for SPT's is explored to provide a comparison between conventional and direct drive system mass.

  17. Oscillation control system for electric motor drive

    DOEpatents

    Slicker, James M.; Sereshteh, Ahmad

    1988-01-01

    A feedback system for controlling mechanical oscillations in the torsionally complaint drive train of an electric or other vehicle. Motor speed is converted in a processor to estimate state signals in which a plant model which are used to electronically modify thetorque commands applied to the motor.

  18. Oscillation control system for electric motor drive

    DOEpatents

    Slicker, J.M.; Sereshteh, A.

    1988-08-30

    A feedback system for controlling mechanical oscillations in the torsionally complaint drive train of an electric or other vehicle. Motor speed is converted in a processor to estimate state signals in which a plant model which are used to electronically modify the torque commands applied to the motor. 5 figs.

  19. Leakage current and commutation losses reduction in electric drives for Hybrid Electric Vehicle

    NASA Astrophysics Data System (ADS)

    Miliani, El Hadj

    2014-06-01

    Nowadays, leakage current and inverter losses, produced by adjustable-speed AC drive systems become one of the main interested subject for researchers on Electric Vehicle (EV) and Hybrid Electric Vehicle (HEV) technology. The continuous advancements in solid state device engineering have considerably minimized the switching transients for power switches but the high dv/dt and high switching frequency have caused many adverse effects such as shaft voltage, bearing current, leakage current and electromagnetic interference (EMI). The major objective of this paper is to investigate and suppress of the adverse effects of a PWM inverter feeding AC motor in EV and HEV. A technique to simultaneously reduce the leakage current and the switching losses is presented in this paper. Based on a discontinuous space vector pulse width modulation (DSVPWM) and a modular switches gate resistance, inverter losses and leakage current are reduced. Algorithms are presented and implemented on a DSP controller and experimental results are presented.

  20. Improved SCR ac Motor Controller for Battery Powered Urban Electric Vehicles

    NASA Technical Reports Server (NTRS)

    Latos, T. S.

    1982-01-01

    An improved ac motor controller, which when coupled to a standard ac induction motor and a dc propulsion battery would provide a complete electric vehicle power train with the exception of the mechanical transmission and drive wheels was designed. In such a system, the motor controller converts the dc electrical power available at the battery terminals to ac electrical power for the induction motor in response to the drivers commands. The performance requirements of a hypothetical electric vehicle with an upper weight bound of 1590 kg (3500 lb) were used to determine the power rating of the controller. Vehicle acceleration capability, top speed, and gradeability requisites were contained in the Society of Automotive Engineers (SAE) Schedule 227a(d) driving cycle. The important capabilities contained in this driving cycle are a vehicle acceleration requirement of 0 to 72.4 kmph (0 to 45 mph) in 28 seconds a top speed of 88.5 kmph (55 mph), and the ability to negotiate a 10% grade at 48 kmph (30 mph). A 10% grade is defined as one foot of vertical rise per 10 feet of horizontal distance.

  1. Advanced AC permanent magnet axial flux disc motor for electric passenger vehicle

    NASA Technical Reports Server (NTRS)

    Kliman, G. B.

    1982-01-01

    An ac permanent magnet axial flux disc motor was developed to operate with a thyristor load commutated inverter as part of an electric vehicle drive system. The motor was required to deliver 29.8 kW (40 hp) peak and 10.4 kW (14 hp) average with a maximum speed of 11,000 rpm. It was also required to run at leading power factor to commutate the inverter. Three motors were built.

  2. Equivalent Electrical Circuit Representations of AC Quantized Hall Resistance Standards

    PubMed Central

    Cage, M. E.; Jeffery, A.; Matthews, J.

    1999-01-01

    We use equivalent electrical circuits to analyze the effects of large parasitic impedances existing in all sample probes on four-terminal-pair measurements of the ac quantized Hall resistance RH. The circuit components include the externally measurable parasitic capacitances, inductances, lead resistances, and leakage resistances of ac quantized Hall resistance standards, as well as components that represent the electrical characteristics of the quantum Hall effect device (QHE). Two kinds of electrical circuit connections to the QHE are described and considered: single-series “offset” and quadruple-series. (We eliminated other connections in earlier analyses because they did not provide the desired accuracy with all sample probe leads attached at the device.) Exact, but complicated, algebraic equations are derived for the currents and measured quantized Hall voltages for these two circuits. Only the quadruple-series connection circuit meets our desired goal of measuring RH for both ac and dc currents with a one-standard-deviation uncertainty of 10−8 RH or less during the same cool-down with all leads attached at the device. The single-series “offset” connection circuit meets our other desired goal of also measuring the longitudinal resistance Rx for both ac and dc currents during that same cool-down. We will use these predictions to apply small measurable corrections, and uncertainties of the corrections, to ac measurements of RH in order to realize an intrinsic ac quantized Hall resistance standard of 10−8 RH uncertainty or less.

  3. Trapping of Rb Atoms by ac Electric Fields

    SciTech Connect

    Schlunk, Sophie; Marian, Adela; Geng, Peter; Meijer, Gerard; Schoellkopf, Wieland; Mosk, Allard P.

    2007-06-01

    We demonstrate trapping of an ultracold gas of neutral atoms in a macroscopic ac electric trap. Three-dimensional confinement is obtained by switching between two saddle-point configurations of the electric field. Stable trapping is observed in a narrow range of switching frequencies around 60 Hz. The dynamic confinement of the atoms is directly visualized at different phases of the ac switching cycle. We observe about 10{sup 5} Rb atoms in the 1 mm{sup 3} large and several microkelvins deep trap with a lifetime of approximately 5 s.

  4. New Technique of AC drive in Tokamak using Permanent Magnets

    NASA Astrophysics Data System (ADS)

    Matteucci, Jackson; Zolfaghari, Ali

    2013-10-01

    This study investigates a new technique of capturing the rotational energy of alternating permanent magnets in order to inductively drive an alternating current in tokamak devices. The use of rotational motion bypasses many of the pitfalls seen in typical inductive and non-inductive current drives. Three specific designs are presented and assessed in the following criteria: the profile of the current generated, the RMS loop voltage generated as compared to the RMS power required to maintain it, the system's feasibility from an engineering perspective. All of the analysis has been done under ideal E&M conditions using the Maxwell 3D program. Preliminary results indicate that it is possible to produce an over 99% purely toroidal current with a RMS d Φ/dt of over 150 Tm2/s, driven by 20 MW or less of rotational power. The proposed mechanism demonstrates several key advantages including an efficient mechanical drive system, the generation of pure toroidal currents, and the potential for a quasi-steady state fusion reactor. The following quantities are presented for various driving frequencies and magnet strengths: plasma current generated, loop voltage, torque and power required. This project has been supported by DOE Funding under the SULI program.

  5. Wind-powered asynchronous AC/DC/AC converter system. [for electric power supply regulation

    NASA Technical Reports Server (NTRS)

    Reitan, D. K.

    1973-01-01

    Two asynchronous ac/dc/ac systems are modelled that utilize wind power to drive a variable or constant hertz alternator. The first system employs a high power 60-hertz inverter tie to the large backup supply of the power company to either supplement them from wind energy, storage, or from a combination of both at a preset desired current; rectifier and inverter are identical and operate in either mode depending on the silicon control rectifier firing angle. The second system employs the same rectification but from a 60-hertz alternator arrangement; it provides mainly dc output, some sinusoidal 60-hertz from the wind bus and some high harmonic content 60-hertz from an 800-watt inverter.

  6. C/NOFS Observations of AC Electric Field Fields Associated with Equatorial Spread-F

    NASA Technical Reports Server (NTRS)

    Pfaff, R.; Liebrecht, C.

    2009-01-01

    The Vector Electric Field Investigation (VEFI) on the C/NOFS equatorial satellite provides a unique data set in which to acquire detailed knowledge of irregularities associated with the equatorial ionosphere and in particular with spread-F depletions. We present vector AC electric field observations, primarily gathered within the ELF band (1 Hz to 250 Hz) on C/NOFS that address a variety of key questions regarding how plasma irregularities, from meter to kilometer scales, are created and evolve. The data will be used to explore the anisotropy/isotropy of the waves, their wavelength and phase velocity, as well as their spectral distributions. When analyzed in conjunction with the driving DC electric fields and detailed plasma number density measurements, the combined data reveal important information concerning the instability mechanisms themselves. We also present high resolution, vector measurements of intense lower hybrid waves that have been detected on numerous occasions by the VEFI burst memory VLF electric field channels.

  7. Lipid Bilayer Vesicle Dynamics in AC Electric Fields

    NASA Astrophysics Data System (ADS)

    McConnell, Lane; Vlahovska, Petia; Miksis, Michael

    2014-11-01

    Vesicles are closed, fluid-filled lipid bilayers which are mechanically similar to biological cells and which undergo shape transitions in the presence of electric fields. Here we model the vesicle membrane as an infinitely thin, capacitive, area-incompressible interface with the surrounding fluids acting as charge-advecting leaky dielectrics. We then implement the boundary integral method to numerically investigate the dynamics of a vesicle in various AC electric field profiles. Our numerical results are then compared with recent small deformation theory and experimental data. We also note our observation of a new theoretical vesicle behavior that has yet to be observed experimentally.

  8. Microfluidic flow-focusing in ac electric fields.

    PubMed

    Tan, Say Hwa; Semin, Benoît; Baret, Jean-Christophe

    2014-03-21

    We demonstrate the control of droplet sizes by an ac voltage applied across microelectrodes patterned around a flow-focusing junction. The electrodes do not come in contact with the fluids to avoid electrochemical effects. We found several regimes of droplet production in electric fields, controlled by the connection of the chip, the conductivity of the dispersed phase and the frequency of the applied field. A simple electrical modelling of the chip reveals that the effective voltage at the tip of the liquid to be dispersed controls the production mechanism. At low voltages (≲ 600 V), droplets are produced in dripping regime; the droplet size is a function of the ac electric field. The introduction of an effective capillary number that takes into account the Maxwell stress can explain the dependance of droplet size with the applied voltage. At higher voltages (≳ 600 V), jets are observed. The stability of droplet production is a function of the fluid conductivity and applied field frequency reported in a set of flow diagrams. PMID:24401868

  9. Mechanism for AC Electric Field Deflection of Flames

    NASA Astrophysics Data System (ADS)

    Chemama, Michael; Bishop, Kyle; Cademartiri, Ludovico; Brenner, Michael P.; Whitesides, Georges M.

    2010-11-01

    Effects of electric fields on flames have been observed and studied since the 19th century. It is well known that the presence of an electric field can modify the shape of a burner or candle-like diffusion flame. Most experimental observations and theoretical analyses focused on DC fields. Recent experiments show that a flame can also be bent and even put out by an AC field. To explain how a zero time average cause can give rise to a net effect on the flame we develop a perturbation theory of the combustion equations modified to allow for the presence of the field and completed by Maxwell's equation. Theoretical and numerical analyses of the equations indeed show that the AC field creates a force whose magnitude is comparable to gravity for high enough fields (1e5 V/m). The dependency of this critical field on the frequency and the effect on the flame shape are also obtained and compared to experimental results.

  10. Long-range response in ac electricity grids.

    PubMed

    Jung, Daniel; Kettemann, Stefan

    2016-07-01

    Local changes in the topology of electricity grids can cause overloads far away from the disturbance [D. Witthaut and M. Timme, Eur. Phys. J. B 86, 377 (2013)EPJBFY1434-602810.1140/epjb/e2013-40469-4], making the prediction of the robustness against changes in the topology-for example, caused by power outages or grid extensions-a challenging task. The impact of single-line additions on the long-range response of dc electricity grids has recently been studied [D. Labavić, R. Suciu, H. Meyer-Ortmanns, and S. Kettemann, Eur. Phys. J.: Spec. Top. 223, 2517 (2014)1951-635510.1140/epjst/e2014-02273-0]. By solving the real part of the static ac load flow equations, we conduct a similar investigation for ac grids. In a regular two-dimensional grid graph with cyclic boundary conditions, we find a power law decay for the change of power flow as a function of distance to the disturbance over a wide range of distances. The power exponent increases and saturates for large system sizes. By applying the same analysis to the German transmission grid topology, we show that also in real-world topologies a long-ranged response can be found. PMID:27575148

  11. Long-range response in ac electricity grids

    NASA Astrophysics Data System (ADS)

    Jung, Daniel; Kettemann, Stefan

    2016-07-01

    Local changes in the topology of electricity grids can cause overloads far away from the disturbance [D. Witthaut and M. Timme, Eur. Phys. J. B 86, 377 (2013), 10.1140/epjb/e2013-40469-4], making the prediction of the robustness against changes in the topology—for example, caused by power outages or grid extensions—a challenging task. The impact of single-line additions on the long-range response of dc electricity grids has recently been studied [D. Labavić, R. Suciu, H. Meyer-Ortmanns, and S. Kettemann, Eur. Phys. J.: Spec. Top. 223, 2517 (2014), 10.1140/epjst/e2014-02273-0]. By solving the real part of the static ac load flow equations, we conduct a similar investigation for ac grids. In a regular two-dimensional grid graph with cyclic boundary conditions, we find a power law decay for the change of power flow as a function of distance to the disturbance over a wide range of distances. The power exponent increases and saturates for large system sizes. By applying the same analysis to the German transmission grid topology, we show that also in real-world topologies a long-ranged response can be found.

  12. Long-range response in ac electricity grids.

    PubMed

    Jung, Daniel; Kettemann, Stefan

    2016-07-01

    Local changes in the topology of electricity grids can cause overloads far away from the disturbance [D. Witthaut and M. Timme, Eur. Phys. J. B 86, 377 (2013)EPJBFY1434-602810.1140/epjb/e2013-40469-4], making the prediction of the robustness against changes in the topology-for example, caused by power outages or grid extensions-a challenging task. The impact of single-line additions on the long-range response of dc electricity grids has recently been studied [D. Labavić, R. Suciu, H. Meyer-Ortmanns, and S. Kettemann, Eur. Phys. J.: Spec. Top. 223, 2517 (2014)1951-635510.1140/epjst/e2014-02273-0]. By solving the real part of the static ac load flow equations, we conduct a similar investigation for ac grids. In a regular two-dimensional grid graph with cyclic boundary conditions, we find a power law decay for the change of power flow as a function of distance to the disturbance over a wide range of distances. The power exponent increases and saturates for large system sizes. By applying the same analysis to the German transmission grid topology, we show that also in real-world topologies a long-ranged response can be found.

  13. 28. View of operating machinery shoeing electric motor, clutch drive ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    28. View of operating machinery shoeing electric motor, clutch drive wheel and hand-painted alignment dial, (Nov. 25, 1988) - University Heights Bridge, Spanning Harlem River at 207th Street & West Harlem Road, New York County, NY

  14. 7. DETAIL OF GATE LIFTING GEARS AND ELECTRIC DRIVE MOTOR ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. DETAIL OF GATE LIFTING GEARS AND ELECTRIC DRIVE MOTOR (LEFT BACKGROUND) FOR NEW YORK CANAL HEADWORKS. VIEW TO EAST. - Boise Project, Boise River Diversion Dam, Across Boise River, Boise, Ada County, ID

  15. Particle Agglomeration in Bipolar Barb Agglomerator Under AC Electric Field

    NASA Astrophysics Data System (ADS)

    Huang, Chao; Ma, Xiuqin; Sun, Youshan; Wang, Meiyan; Zhang, Changping; Lou, Yueya

    2015-04-01

    The development of an efficient technology for removing fine particles in flue gas is essential as the haze is becoming more and more serious. To improve agglomeration effectiveness of fine particles, a dual zone electric agglomeration device consisting of a charging chamber and an agglomeration chamber with bipolar barb electrodes was developed. The bipolar barb electric agglomerator with a polar distance of 200 mm demonstrates good agglomeration effectiveness for particles with a size less than 8.0 μm under applied AC electric field. An optimal condition for achieving better agglomeration effectiveness was found to be as follows: flue gas flow velocity of 3.00 m/s, particle concentration of 2.00 g/m3, output voltage of 35 kV and length of the barb of 16 mm. In addition, 4.0-6.0 μm particles have the best effectiveness with the variation of particle volume occupancy of -3.2. supported by the Key Technology R&D Program of Hebei, China (No. 13211207D)

  16. AC Electric Field Activated Shape Memory Polymer Composite

    NASA Technical Reports Server (NTRS)

    Kang, Jin Ho; Siochi, Emilie J.; Penner, Ronald K.; Turner, Travis L.

    2011-01-01

    Shape memory materials have drawn interest for applications like intelligent medical devices, deployable space structures and morphing structures. Compared to other shape memory materials like shape memory alloys (SMAs) or shape memory ceramics (SMCs), shape memory polymers (SMPs) have high elastic deformation that is amenable to tailored of mechanical properties, have lower density, and are easily processed. However, SMPs have low recovery stress and long response times. A new shape memory thermosetting polymer nanocomposite (LaRC-SMPC) was synthesized with conductive fillers to enhance its thermo-mechanical characteristics. A new composition of shape memory thermosetting polymer nanocomposite (LaRC-SMPC) was synthesized with conductive functionalized graphene sheets (FGS) to enhance its thermo-mechanical characteristics. The elastic modulus of LaRC-SMPC is approximately 2.7 GPa at room temperature and 4.3 MPa above its glass transition temperature. Conductive FGSs-doped LaRC-SMPC exhibited higher conductivity compared to pristine LaRC SMP. Applying an electric field at between 0.1 Hz and 1 kHz induced faster heating to activate the LaRC-SMPC s shape memory effect relative to applying DC electric field or AC electric field at frequencies exceeding1 kHz.

  17. Kondo physics in the single-electron transistor with ac driving

    SciTech Connect

    Nordlander, Peter; Wingreen, Ned S.; Meir, Yigal; Langreth, David C.

    2000-01-15

    Using a time-dependent Anderson Hamiltonian, a quantum dot with an ac voltage applied to a nearby gate is investigated. A rich dependence of the linear response conductance on the external frequency and driving amplitude is demonstrated. At low frequencies a sufficiently strong ac potential produces sidebands of the Kondo peak in the spectral density of the dot, and a slow, roughly logarithmic decrease in conductance over several decades of frequency. At intermediate frequencies, the conductance of the dot displays an oscillatory behavior due to the appearance of Kondo resonances of the satellites of the dot level. At high frequencies, the conductance of the dot can vary rapidly due to the interplay between photon-assisted tunneling and the Kondo resonance. (c) 2000 The American Physical Society.

  18. Electrical motor/generator drive apparatus and method

    DOEpatents

    Su, Gui Jia

    2013-02-12

    The present disclosure includes electrical motor/generator drive systems and methods that significantly reduce inverter direct-current (DC) bus ripple currents and thus the volume and cost of a capacitor. The drive methodology is based on a segmented drive system that does not add switches or passive components but involves reconfiguring inverter switches and motor stator winding connections in a way that allows the formation of multiple, independent drive units and the use of simple alternated switching and optimized Pulse Width Modulation (PWM) schemes to eliminate or significantly reduce the capacitor ripple current.

  19. Electromagnetic interference assessment of an ion drive electric propulsion system

    NASA Technical Reports Server (NTRS)

    Whittlesey, A. C.

    1981-01-01

    An electric propulsion thrust system has the capability of providing a high specific impulse for long duration scientific missions in space. The EMI from the elements of an ion engine was characterized. The compatibility of ion drive electric propulsion systems with typical interplanetary spacecraft engineering was predicted.

  20. An adaptive fuzzy controller for permanent-magnet AC servo drives

    SciTech Connect

    Le-Huy, H.

    1995-12-31

    This paper presents a theoretical study on a model-reference adaptive fuzzy logic controller for vector-controlled permanent-magnet ac servo drives. In the proposed system, fuzzy logic is used to implement the direct controller as well as the adaptation mechanism. The operation of the direct fuzzy controller and the fuzzy logic based adaptation mechanism is studied. The control performance of the adaptive fuzzy controller is evaluated by simulation for various operating conditions. The results are compared with that provided by a non-adaptive fuzzy controller. The implementation of proposed adaptive fuzzy controller is discussed.

  1. Fuzzy based power factor improvement strategy for a multiple connected AC-DC converter fed drive

    NASA Astrophysics Data System (ADS)

    Radhakrishnan, N.; Muthiah, Ramaswamy

    2012-01-01

    The main focus of this paper is to design a Fuzzy based control algorithm to realize an improvement in the input power factor of a multiple connected AC-DC converter fed drive system. It incorporates the role of fuzzy inference principles to generate appropriate PWM pulses for the power switches at the second stage of the power module. The philosophy is developed, with a view to reshape the input current phasor and enables it to align with the supply voltage wave in the perspective of improving the input power factor. The closed loop scheme evaluated using MATLAB based simulation exhibits an enhancement in supply power factor over a range of operating loads in addition to illustrating the speed regulating capability of the drive.

  2. Colleges Drive Research on Electric Cars

    ERIC Educational Resources Information Center

    Basken, Paul

    2009-01-01

    As the General Motors Corporation shuts assembly plants and veers toward bankruptcy, the lonely remnants of one of its top technological achievements--the first modern mass-produced electric car--lie scattered across a few dozen American college campuses. GM produced and leased to customers more than 1,000 "EV1" automobiles beginning in 1996. In…

  3. Universal features of particle motion in ac electric fields

    NASA Astrophysics Data System (ADS)

    Niemeyer, L.; Seeger, M.

    2015-11-01

    Mobile particles present as contaminants in high voltage gas insulated switchgear (GIS) may constitute a risk for insulation failure. The understanding of their motion in the electric field of the insulation gap is therefore essential for quality control in manufacturing, commissioning and in service monitoring. Published research on particle motion in ac electric fields has shown that this rather complex process depends on numerous parameters, many of which remain unknown under practical conditions. This renders modelling, generalization of experimental data and practical application difficult. The scope of this paper therefore is to develop a unified description of particle motion which minimizes the number of controlling parameters, enables the comparison of experimental data and allows simple interpretation relations to be derived. This is achieved by making the controlling equations dimensionless with an appropriate choice of reference values and by using simplifying assumptions for the specific conditions prevailing in GIS. The resulting generalized description of the process can then be summarized in the form of 2D patterns (dynamic maps). Approximate scaling relations are derived between specific features of these patterns and particle-related parameters. A reference case is discussed in detail. The non-linear character of the equation of motion suggests that the particle motion may be a deterministic process with chaotic features. This is confirmed by a preliminary chaos-theoretical analysis of the process.

  4. FY2014 Electric Drive Technologies Annual Progress Report

    SciTech Connect

    2014-12-01

    The Electric Drive Technologies research and development (R&D) subprogram within the DOE Vehicle Technologies Office (VTO) provides support and guidance for many cutting-edge automotive technologies under development. Research is focused on developing power electronics (PE), electric motor, and traction drive system (TDS) technologies that will reduce system cost and improve their efficiency in transforming battery energy to useful work. The R&D is also aimed at better understanding and improving how various components of tomorrow’s automobiles will function as a unified system to improve fuel efficiency.

  5. Electric machine and current source inverter drive system

    DOEpatents

    Hsu, John S

    2014-06-24

    A drive system includes an electric machine and a current source inverter (CSI). This integration of an electric machine and an inverter uses the machine's field excitation coil for not only flux generation in the machine but also for the CSI inductor. This integration of the two technologies, namely the U machine motor and the CSI, opens a new chapter for the component function integration instead of the traditional integration by simply placing separate machine and inverter components in the same housing. Elimination of the CSI inductor adds to the CSI volumetric reduction of the capacitors and the elimination of PMs for the motor further improve the drive system cost, weight, and volume.

  6. Understanding Electric Interactions in Suspensions in Gradient AC Electric Fields I:. Experimental

    NASA Astrophysics Data System (ADS)

    Shen, Yan; Qiu, Zhiyong; Tada, Shigeru

    When neutrally buoyant poly alpha olefin particles in corn oil were exposed to a gradient ac electric field generated by a spatially periodic electrode array, these particles experienced the negative dielectrophoresis and instability in all the suspensions of concentration range from 0.01% to 5% (v/v). One critical particle concentration was experimentally determined as 1% (v/v) below which the particles in corn oil were segregated to form island-like structures in the lower electric field regions; and above which, particles only formed straight stripes. The island-like structure was suspended in the lowest electric field area. Specially designed experiments with a suspension of 1.126% (v/v) confirmed that there exists particle instability. Anisotropic properties of electric interactions are responsible for particle instability in all the suspensions of different concentrations and island-like structures were formed only in the dilute suspensions in which the particle instability has enough space to be developed.

  7. DC-AC Cascaded H-Bridge Multilevel Boost Inverter With No Inductors for Electric/Hybrid Electric Vehicle Applications

    SciTech Connect

    Tolbert, Leon M; Ozpineci, Burak; Du, Zhong; Chiasson, John N

    2009-01-01

    This paper presents a cascaded H-bridge multilevel boost inverter for electric vehicle (EV) and hybrid EV (HEV) applications implemented without the use of inductors. Currently available power inverter systems for HEVs use a dc-dc boost converter to boost the battery voltage for a traditional three-phase inverter. The present HEV traction drive inverters have low power density, are expensive, and have low efficiency because they need a bulky inductor. A cascaded H-bridge multilevel boost inverter design for EV and HEV applications implemented without the use of inductors is proposed in this paper. Traditionally, each H-bridge needs a dc power supply. The proposed design uses a standard three-leg inverter (one leg for each phase) and an H-bridge in series with each inverter leg which uses a capacitor as the dc power source. A fundamental switching scheme is used to do modulation control and to produce a five-level phase voltage. Experiments show that the proposed dc-ac cascaded H-bridge multilevel boost inverter can output a boosted ac voltage without the use of inductors.

  8. Concentrating membrane proteins using asymmetric traps and AC electric fields.

    PubMed

    Cheetham, Matthew R; Bramble, Jonathan P; McMillan, Duncan G G; Krzeminski, Lukasz; Han, Xiaojun; Johnson, Benjamin R G; Bushby, Richard J; Olmsted, Peter D; Jeuken, Lars J C; Marritt, Sophie J; Butt, Julea N; Evans, Stephen D

    2011-05-01

    Membrane proteins are key components of the plasma membrane and are responsible for control of chemical ionic gradients, metabolite and nutrient transfer, and signal transduction between the interior of cells and the external environment. Of the genes in the human genome, 30% code for membrane proteins (Krogh et al. J. Mol. Biol.2001, 305, 567). Furthermore, many FDA-approved drugs target such proteins (Overington et al. Nat. Rev. Drug Discovery 2006, 5, 993). However, the structure-function relationships of these are notably sparse because of difficulties in their purification and handling outside of their membranous environment. Methods that permit the manipulation of membrane components while they are still in the membrane would find widespread application in separation, purification, and eventual structure-function determination of these species (Poo et al. Nature 1977, 265, 602). Here we show that asymmetrically patterned supported lipid bilayers in combination with AC electric fields can lead to efficient manipulation of charged components. We demonstrate the concentration and trapping of such components through the use of a "nested trap" and show that this method is capable of yielding an approximately 30-fold increase in the average protein concentration. Upon removal of the field, the material remains trapped for several hours as a result of topographically restricted diffusion. Our results indicate that this method can be used for concentrating and trapping charged membrane components while they are still within their membranous environment. We anticipate that our approach could find widespread application in the manipulation and study of membrane proteins.

  9. Concentrating membrane proteins using asymmetric traps and AC electric fields.

    PubMed

    Cheetham, Matthew R; Bramble, Jonathan P; McMillan, Duncan G G; Krzeminski, Lukasz; Han, Xiaojun; Johnson, Benjamin R G; Bushby, Richard J; Olmsted, Peter D; Jeuken, Lars J C; Marritt, Sophie J; Butt, Julea N; Evans, Stephen D

    2011-05-01

    Membrane proteins are key components of the plasma membrane and are responsible for control of chemical ionic gradients, metabolite and nutrient transfer, and signal transduction between the interior of cells and the external environment. Of the genes in the human genome, 30% code for membrane proteins (Krogh et al. J. Mol. Biol.2001, 305, 567). Furthermore, many FDA-approved drugs target such proteins (Overington et al. Nat. Rev. Drug Discovery 2006, 5, 993). However, the structure-function relationships of these are notably sparse because of difficulties in their purification and handling outside of their membranous environment. Methods that permit the manipulation of membrane components while they are still in the membrane would find widespread application in separation, purification, and eventual structure-function determination of these species (Poo et al. Nature 1977, 265, 602). Here we show that asymmetrically patterned supported lipid bilayers in combination with AC electric fields can lead to efficient manipulation of charged components. We demonstrate the concentration and trapping of such components through the use of a "nested trap" and show that this method is capable of yielding an approximately 30-fold increase in the average protein concentration. Upon removal of the field, the material remains trapped for several hours as a result of topographically restricted diffusion. Our results indicate that this method can be used for concentrating and trapping charged membrane components while they are still within their membranous environment. We anticipate that our approach could find widespread application in the manipulation and study of membrane proteins. PMID:21476549

  10. Development of a computer algorithm for the analysis of variable-frequency AC drives: Case studies included

    NASA Technical Reports Server (NTRS)

    Kankam, M. David; Benjamin, Owen

    1991-01-01

    The development of computer software for performance prediction and analysis of voltage-fed, variable-frequency AC drives for space power applications is discussed. The AC drives discussed include the pulse width modulated inverter (PWMI), a six-step inverter and the pulse density modulated inverter (PDMI), each individually connected to a wound-rotor induction motor. Various d-q transformation models of the induction motor are incorporated for user-selection of the most applicable model for the intended purpose. Simulation results of selected AC drives correlate satisfactorily with published results. Future additions to the algorithm are indicated. These improvements should enhance the applicability of the computer program to the design and analysis of space power systems.

  11. Using fleets of electric-drive vehicles for grid support

    NASA Astrophysics Data System (ADS)

    Tomić, Jasna; Kempton, Willett

    Electric-drive vehicles can provide power to the electric grid when they are parked (vehicle-to-grid power). We evaluated the economic potential of two utility-owned fleets of battery-electric vehicles to provide power for a specific electricity market, regulation, in four US regional regulation services markets. The two battery-electric fleet cases are: (a) 100 Th!nk City vehicle and (b) 252 Toyota RAV4. Important variables are: (a) the market value of regulation services, (b) the power capacity (kW) of the electrical connections and wiring, and (c) the energy capacity (kWh) of the vehicle's battery. With a few exceptions when the annual market value of regulation was low, we find that vehicle-to-grid power for regulation services is profitable across all four markets analyzed. Assuming now more than current Level 2 charging infrastructure (6.6 kW) the annual net profit for the Th!nk City fleet is from US 7000 to 70,000 providing regulation down only. For the RAV4 fleet the annual net profit ranges from US 24,000 to 260,000 providing regulation down and up. Vehicle-to-grid power could provide a significant revenue stream that would improve the economics of grid-connected electric-drive vehicles and further encourage their adoption. It would also improve the stability of the electrical grid.

  12. Wavelet analysis of electric adjustable speed drive waveforms

    SciTech Connect

    Czarkowski, D.; Domijan, A. Jr.

    1998-10-01

    The three most common adjustable speed drives (ASDs) used in HVAC equipment, namely, pulse-width modulated (PWM) induction drive, brushless-dc drive, and switched-reluctance drive, generate non-periodic and nonstationary electric waveforms with sharp edges and transients. Deficiencies of Fourier transform methods in analysis of such ASD waveforms prompted an application of the wavelet transform. Results of discrete wavelet transform (DWT) analysis of PWM inverter-fed motor waveforms are presented. The best mother wavelet for analysis of the recorded waveforms is selected. Data compression properties of the selected mother wavelet are compared to those of the fast Fourier transform (FFT). Multilevel feature detection of ASD waveforms using the DWT is shown.

  13. Droplet condensation on superhydrophobic surfaces with enhanced dewetting under a tangential AC electric field

    NASA Astrophysics Data System (ADS)

    Yan, Xinzhu; Li, Jian; Li, Licheng; Huang, Zhengyong; Wang, Feipeng; Wei, Yuan

    2016-10-01

    In this Letter, the dewetting behavior of superhydrophobic condensing surfaces under a tangential AC electric field is reported. The surface coverage of condensed droplets only exhibits a negligible increase with time. The jumping frequency of droplets is enhanced. The AC electric field motivates the dynamic transition of droplets from stretch to recoil, resulting in the counterforce propelling droplet jumping. The considerable horizontal component of jumping velocity facilitates droplet departure from superhydrophobic surfaces. Both the amplitude and frequency of AC voltage are important factors for droplet departure and dewetting effect. Thereby, the tangential electric field provides a unique and easily implementable approach to enhance droplet removal from superhydrophobic condensing surfaces.

  14. Electric Motor Thermal Management for Electric Traction Drives (Presentation)

    SciTech Connect

    Bennion, K.; Cousineau, J.; Moreno, G.

    2014-09-01

    Thermal constraints place significant limitations on how electric motors ultimately perform. Finite element analysis and computational fluid dynamics modeling approaches are being increasingly utilized in the design and analysis of electric motors. As the models become more sophisticated, it is important to have detailed and accurate knowledge of material thermal properties and convective heat transfer coefficients. In this work, the thermal properties and inter-lamination thermal contact resistances were measured for different stator lamination materials. Also, convective heat transfer coefficients of automatic transmission fluid (ATF) jets were measured to better understand the heat transfer of ATF impinging on motor copper windings. Experiments were carried out at various ATF temperatures and jet velocities to quantify the influence of these parameters on heat transfer coefficients.

  15. Fast electric dipole transitions in Ra-Ac nuclei

    SciTech Connect

    Ahmad, I.

    1985-01-01

    Lifetime of levels in /sup 225/Ra, /sup 225/Ac, and /sup 227/Ac have been measured by delayed coincidence techniques and these have been used to determine the E1 gamma-ray transition probabilities. The reduced E1 transition probabilities. The reduced E1 transition probabilities in /sup 225/Ra and /sup 225/Ac are about two orders of magnitude larger than the values in mid-actinide nuclei. On the other hand, the E1 rate in /sup 227/Ac is similar to those measured in heavier actinides. Previous studies suggest the presence of octupole deformation in all the three nuclei. The present investigation indicates that fast E1 transitions occur for nuclei with octupole deformation. However, the studies also show that there is no one-to-one correspondence between E1 rate and octupole deformation. 13 refs., 4 figs.

  16. Understanding Electric Interactions in Suspensions in Gradient AC Electric Fields II:. Simulations and Application Exploration

    NASA Astrophysics Data System (ADS)

    Tada, Shigeru; Shen, Yan; Jacqmin, David; Fu, Bingmei; Qiu, Zhiyong

    We used numerical simulations of a continuous model and the molecular dynamics model to understand the particle instability, formation of island-like structures and existence of one critical particle concentration of 1% (v/v) for formation of island-like structures in the suspension in a gradient AC electric field reported in Paper I. The simulations of the continuous model show that the critical concentration of 1% (v/v) is the concentration of which the particles of a suspension are just fully filling the lower field region finally. According to the MD simulations, the particles instability does exist in the corn oil in a gradient AC electric field, anisotropic polarization interactions among the particles are responsible for the particle instability and have memory, and the memory is still kept even when the particles are transported by a dielectrophoresis force. The island-like structures can be regarded as signature of the memory. We explored possibilities to apply our findings in biomedical fields.

  17. Split-Stirling-cycle displacer linear-electric drive

    NASA Technical Reports Server (NTRS)

    Ackermann, R. A.; Bhate, S. K.; Byrne, D. V.

    1983-01-01

    The retrofit of a 1/4-W split-Stirling cooler with a linear driven on the displacer was achieved and its performance characterized. The objective of this work was to demonstrate that a small linear motor could be designed to meet the existing envelope specifications of the cooler and that an electric linear drive on the displacer could improve the cooler's reliability and performance. The paper describes the characteristics of this motor and presents cooler test results.

  18. Numeric description of space charge in polyethylene under ac electric fields

    NASA Astrophysics Data System (ADS)

    Zhao, J.; Xu, Z.; Chen, G.; Lewin, P. L.

    2010-12-01

    Space charge in polyethylene-based insulation materials and its effect on the local electric field under a dc environment have been extensively examined over the last few decades while the behavior of space charge under ac stress has received less attention. Space charge phenomenon under ac electric fields becomes an important issue with increased operating field strength in many applications, such as next generation high voltage cables. In this paper, a bipolar charge transport model has been developed to simulate space charge in polymers under ac electric fields. Obtained simulation results show that there is a small quantity of phase-dependent bipolar charge accumulation in the vicinity of the electrodes that does not move into the bulk under ac stress. This causes a slight distortion of the local field in the bulk. However, at lower frequencies less than 1 Hz, there is increased charge accumulation and penetration. Comparison with available experimental data suggests that the model is capable of describing the underlying physics of charge behavior when a dielectric material is subjected to ac electric fields. Due to the weak charge movement in the bulk, the conduction current density is small and hence the displacement component dominates the total current density and this increases linearly with ac frequency.

  19. Electric field in an AC dielectric barrier discharge overlapped with a nanosecond pulse discharge

    NASA Astrophysics Data System (ADS)

    Goldberg, Benjamin M.; Shkurenkov, Ivan; Adamovich, Igor V.; Lempert, Walter R.

    2016-08-01

    The effect of ns discharge pulses on the AC barrier discharge in hydrogen in plane-to-plane geometry is studied using time-resolved measurements of the electric field in the plasma. The AC discharge was operated at a pressure of 300 Torr at frequencies of 500 and 1750 Hz, with ns pulses generated when the AC voltage was near zero. The electric field vector is measured by ps four-wave mixing technique, which generates coherent IR signal proportional to the square of electric field. Absolute calibration was done using an electrostatic (sub-breakdown) field applied to the discharge electrodes, when no plasma was generated. The results are compared with one-dimensional kinetic modeling of the AC discharge and the nanosecond pulse discharge, predicting behavior of both individual micro-discharges and their cumulative effect on the electric field distribution in the electrode gap, using stochastic averaging based on the experimental micro-discharge temporal probability distribution during the AC period. Time evolution of the electric field in the AC discharge without ns pulses, controlled by a superposition of random micro-discharges, exhibits a nearly ‘flat top’ distribution with the maximum near breakdown threshold, reproduced quite well by kinetic modeling. Adding ns pulse discharges on top of the AC voltage waveform changes the AC discharge behavior in a dramatic way, inducing transition from random micro-discharges to a more regular, near-1D discharge. In this case, reproducible volumetric AC breakdown is produced at a well-defined moment after each ns pulse discharge. During the reproducible AC breakdown, the electric field in the plasma exhibits a sudden drop, which coincides in time with a well-defined current pulse. This trend is also predicted by the kinetic model. Analysis of kinetic modeling predictions shows that this effect is caused by large-volume ionization and neutralization of surface charges on the dielectrics by ns discharge pulses. The present

  20. Test plan for performance testing of the Eaton AC-3 electric vehicle

    SciTech Connect

    Crumley, R.L.; Heiselmann, H.W.

    1985-04-01

    An alternating current (ac) propulsion system for an electric vehicle has been developed and tested by the Eaton Corporation. The test bed vehicle is a modified 1981 Mercury Lynx. The test plan has been prepared specifically for the third modification to this test bed and identified as the Eaton AC-3. The scope of the EG and G testing at INEL to be done on the Eaton AC-3 will include coastdown and dynamometer tests but will not include environmental, on-road, or track testing. Coastdown testing will be performed in accordance with SAE J-1263 (SAE Recommended Practice for Road Load Measurement and Dynamometer Simulation Using Coastdown Techniques).

  1. Storing the Electric Energy Produced by an AC Generator

    ERIC Educational Resources Information Center

    Carvalho, P. Simeao; Lima, Ana Paula; Carvalho, Pedro Simeao

    2010-01-01

    Producing energy from renewable energy sources is nowadays a priority in our society. In many cases this energy comes as electric energy, and when we think about electric energy generators, one major issue is how we can store that energy. In this paper we discuss how this can be done and give some ideas for applications that can serve as a…

  2. An extended car-following model with consideration of the electric vehicle's driving range

    NASA Astrophysics Data System (ADS)

    Tang, Tie-Qiao; Chen, Liang; Yang, Shi-Chun; Shang, Hua-Yan

    2015-07-01

    In this paper, we propose a car-following model to explore the influences of the electric vehicle's driving range on the driving behavior under four traffic situations. The numerical results illustrate that the electric vehicle's behavior of exchanging battery at the charge station can destroy the stability of traffic flow and produce some prominent jams, and that the influences are related to the electric vehicle's driving range, i.e., the shorter the driving range is, the greater the effects are.

  3. Driving Electric Vehicle by EMG Signal Considering Frequency Components

    NASA Astrophysics Data System (ADS)

    Aso, Shinichi; Sasaki, Akinori; Hashimoto, Hiroshi; Ishii, Chiharu

    This paper proposes a useful method driving the electric vehicle by EMG signals (Electromyographic signals) which are filtered on the basis of frequency components which change with muscle contraction. This method estimates strength of muscular tension by a single EMG signal. By our method, user is able to control speed of the electric vehicle by strength of muscular tension. The method of speed control may give user good or bad operation feeling in the meaning of SD (Semantic Differential) method and factor analysis. The operation feeling is evaluated by experiment on EMG interface in cases of using filters or not. As a result, it is shown that operation feeling is influenced by this method.

  4. Electric vehicle drive train with direct coupling transmission

    DOEpatents

    Tankersley, Jerome B.; Boothe, Richard W.; Konrad, Charles E.

    1995-01-01

    An electric vehicle drive train includes an electric motor and an associated speed sensor, a transmission operable in a speed reduction mode or a direct coupled mode, and a controller responsive to the speed sensor for operating the transmission in the speed reduction mode when the motor is below a predetermined value, and for operating the motor in the direct coupled mode when the motor speed is above a predetermined value. The controller reduces the speed of the motor, such as by regeneratively braking the motor, when changing from the speed reduction mode to the direct coupled mode. The motor speed may be increased when changing from the direct coupled mode to the speed reduction mode. The transmission is preferably a single stage planetary gearbox.

  5. Electric vehicle drive train with rollback detection and compensation

    DOEpatents

    Konrad, C.E.

    1994-12-27

    An electric vehicle drive train includes a controller for detecting and compensating for vehicle rollback, as when the vehicle is started upward on an incline. The vehicle includes an electric motor rotatable in opposite directions corresponding to opposite directions of vehicle movement. A gear selector permits the driver to select an intended or desired direction of vehicle movement. If a speed and rotational sensor associated with the motor indicates vehicle movement opposite to the intended direction of vehicle movement, the motor is driven to a torque output magnitude as a nonconstant function of the rollback speed to counteract the vehicle rollback. The torque function may be either a linear function of speed or a function of the speed squared. 6 figures.

  6. Electric vehicle drive train with rollback detection and compensation

    DOEpatents

    Konrad, Charles E.

    1994-01-01

    An electric vehicle drive train includes a controller for detecting and compensating for vehicle rollback, as when the vehicle is started upward on an incline. The vehicle includes an electric motor rotatable in opposite directions corresponding to opposite directions of vehicle movement. A gear selector permits the driver to select an intended or desired direction of vehicle movement. If a speed and rotational sensor associated with the motor indicates vehicle movement opposite to the intended direction of vehicle movement, the motor is driven to a torque output magnitude as a nonconstant function of the rollback speed to counteract the vehicle rollback. The torque function may be either a linear function of speed or a function of the speed squared.

  7. Electric vehicle drive train with direct coupling transmission

    DOEpatents

    Tankersley, J.B.; Boothe, R.W.; Konrad, C.E.

    1995-04-04

    An electric vehicle drive train includes an electric motor and an associated speed sensor, a transmission operable in a speed reduction mode or a direct coupled mode, and a controller responsive to the speed sensor for operating the transmission in the speed reduction mode when the motor is below a predetermined value, and for operating the motor in the direct coupled mode when the motor speed is above a predetermined value. The controller reduces the speed of the motor, such as by regeneratively braking the motor, when changing from the speed reduction mode to the direct coupled mode. The motor speed may be increased when changing from the direct coupled mode to the speed reduction mode. The transmission is preferably a single stage planetary gearbox. 6 figures.

  8. [Effect of air-electric fields on driving and reaction patterns. Test subjects in the car driving simulator (author's transl)].

    PubMed

    Anselm, D; Danner, M; Kirmaier, N; König, H L; Müller-Limmroth, W; Reis, A; Schauerte, W

    1977-06-10

    In the relevant frequency range of about 10 Hertz cars can be considered very largely as Faraday cages and consequently as screens against air-electric fields. This may have a negative influence on driving and reaction patterns as a result. In an extensive investigation 48 subjects in a driving simulator were exposed to definite artificially produced air-electric fields. The self-rating of the performance and concentration of the subjects, reaction times and driving errors were determined. While the reaction times remained practically constant, the driving behavior of the subjects improved.

  9. Road load simulator tests of the Gould Phase I functional model silicon controlled rectifier ac motor controller for electric vehicles

    SciTech Connect

    Gourash, F.

    1984-02-01

    This report presents the test results for a functional model ac motor controller for electric vehicles and a three-phase induction motor which were dynamically tested on the Lewis Research Center road load simulator. Results show that the controller has the capability to meet the SAE-J227a D cycle test schedule and to accelerate a 1576-kg (3456-lb) simulated vehicle to a cruise speed of 88.5 km/hr (55 mph). Combined motor controller efficiency is 72 percent and the power inverter efficiency alone is 89 percent for the cruise region of the D cycle. Steady state test results for motoring, regeneration, and thermal data obtained by operating the simulator as a conventional dynamometer are in agreement with the contractor's previously reported data. The regeneration test results indicate that a reduction in energy requirements for urban driving cycles is attainable with regenerative braking. Test results and data in this report serve as a data base for further development of ac motor controllers and propulsion systems for electric vehicles. The controller uses state-of-the-art silicon controlled rectifier (SCR) power semiconductors and microprocessor-based logic and control circuitry. The controller was developed by Gould Laboratories under a Lewis contract for the Department of Energy's Electric and Hybrid Vehicle program.

  10. Road load simulator tests of the Gould phase 1 functional model silicon controlled rectifier ac motor controller for electric vehicles

    NASA Technical Reports Server (NTRS)

    Gourash, F.

    1984-01-01

    The test results for a functional model ac motor controller for electric vehicles and a three-phase induction motor which were dynamically tested on the Lewis Research Center road load simulator are presented. Results show that the controller has the capability to meet the SAE-J227a D cycle test schedule and to accelerate a 1576-kg (3456-lb) simulated vehicle to a cruise speed of 88.5 km/hr (55 mph). Combined motor controller efficiency is 72 percent and the power inverter efficiency alone is 89 percent for the cruise region of the D cycle. Steady state test results for motoring, regeneration, and thermal data obtained by operating the simulator as a conventional dynamometer are in agreement with the contractor's previously reported data. The regeneration test results indicate that a reduction in energy requirements for urban driving cycles is attainable with regenerative braking. Test results and data in this report serve as a data base for further development of ac motor controllers and propulsion systems for electric vehicles. The controller uses state-of-the-art silicon controlled rectifier (SCR) power semiconductors and microprocessor-based logic and control circuitry. The controller was developed by Gould Laboratories under a Lewis contract for the Department of Energy's Electric and Hybrid Vehicle program.

  11. Statistical Characterization of Medium-Duty Electric Vehicle Drive Cycles

    SciTech Connect

    Prohaska, Robert; Duran, Adam; Ragatz, Adam; Kelly, Kenneth

    2015-05-03

    In an effort to help commercialize technologies for electric vehicles (EVs) through deployment and demonstration projects, the U.S. Department of Energy's (DOE's) American Recovery and Reinvestment Act (ARRA) provided funding to participating U.S. companies to cover part of the cost of purchasing new EVs. Within the medium- and heavy-duty commercial vehicle segment, both Smith Electric Newton and and Navistar eStar vehicles qualified for such funding opportunities. In an effort to evaluate the performance characteristics of the new technologies deployed in these vehicles operating under real world conditions, data from Smith Electric and Navistar medium-duty EVs were collected, compiled, and analyzed by the National Renewable Energy Laboratory's (NREL) Fleet Test and Evaluation team over a period of 3 years. More than 430 Smith Newton EVs have provided data representing more than 150,000 days of operation. Similarly, data have been collected from more than 100 Navistar eStar EVs, resulting in a comparative total of more than 16,000 operating days. Combined, NREL has analyzed more than 6 million kilometers of driving and 4 million hours of charging data collected from commercially operating medium-duty electric vehicles in various configurations. In this paper, extensive duty-cycle statistical analyses are performed to examine and characterize common vehicle dynamics trends and relationships based on in-use field data. The results of these analyses statistically define the vehicle dynamic and kinematic requirements for each vehicle, aiding in the selection of representative chassis dynamometer test cycles and the development of custom drive cycles that emulate daily operation. In this paper, the methodology and accompanying results of the duty-cycle statistical analysis are presented and discussed. Results are presented in both graphical and tabular formats illustrating a number of key relationships between parameters observed within the data set that relate to

  12. A study of some features of ac and dc electric power systems for a space station

    NASA Technical Reports Server (NTRS)

    Hanania, J. I.

    1983-01-01

    This study analyzes certain selected topics in rival dc and high frequency ac electric power systems for a Space Station. The interaction between the Space Station and the plasma environment is analyzed, leading to a limit on the voltage for the solar array and a potential problem with resonance coupling at high frequencies. Certain problems are pointed out in the concept of a rotary transformer, and further development work is indicated in connection with dc circuit switching, special design of a transmission conductor for the ac system, and electric motors. The question of electric shock hazards, particularly at high frequency, is also explored. and a problem with reduced skin resistance and therefore increased hazard with high frequency ac is pointed out. The study concludes with a comparison of the main advantages and disadvantages of the two rival systems, and it is suggested that the choice between the two should be made after further studies and development work are completed.

  13. Resonant tunneling of interacting electrons in an AC electric field

    SciTech Connect

    Elesin, V. F.

    2013-11-15

    The problem of the effect of electron-electron interaction on the static and dynamic properties of a double-barrier nanostructure (resonant tunneling diode (RTD)) is studied in terms of a coherent tunneling model, which includes a set of Schrödinger and Poisson equations with open boundary conditions. Explicit analytical expressions are derived for dc and ac potentials and reduced (active and reactive) currents in the quasi-classical approximation over a wide frequency range. These expressions are used to analyze the frequency characteristics of RTD. It is shown that the interaction can radically change the form of these expressions, especially in the case of a hysteretic I-V characteristic. In this case, the active current and the ac potentials can increase sharply at both low and high frequencies. For this increase to occur, it is necessary to meet quantum regime conditions and to choose a proper working point in the I-V characteristic of RTD. The possibility of appearance of specific plasma oscillations, which can improve the high-frequency characteristics of RTD, is predicted. It is found that the active current can be comparable with the resonant dc current of RTD.

  14. Efficacy of an AC sinusoidal electric field for apoptosis induction in lung carcinoma cells (A549)

    NASA Astrophysics Data System (ADS)

    Park, Hyoun-Hyang; Lee, Seung S.; Hoon Lee, Dae

    2012-08-01

    An AC sinusoidal electric field was applied to lung carcinoma cells for the induction of apoptosis. The occurrence of apoptosis was determined by analysis of Annexin V/PI and DNA fragmentation. Additional evidence of apoptosis was confirmed by caspase-3 cleavage and disruption of mitochondrial membrane potential. These results demonstrated that the expression of apoptosis can be controlled by varying the magnitude and the duration of the field, and that the application of an AC electric field can stimulate the apoptosis via mitochondria-mediated pathway.

  15. Study of DC and AC electric field effect on Pisum sativum seeds growth

    NASA Astrophysics Data System (ADS)

    Mahmood, Bahar; Jaleh, Sojoodi; Yasaman, Yasaie

    2014-07-01

    In this research the effect of electric field on two groups of wet and dry Pisum sativum seeds growth was studied. To generate the required electric field a parallel-plate capacitor with round copper plates of 30 cm diameter was used. The experiments were performed once in fixed exposure duration of 8 min in variable DC electric field of 0.25-1.5 kV/m. The other experiments were performed in variable fields of 50-125 kV/m in fixed exposure duration of 8 min, in two groups of AC and DC electric fields. The experiments were repeated three times. In each experiment 10 seeds were used and there was a sham exposed group for comparison, too. After application of electric field, the seeds were kept for six days in the same growth chamber with the temperature of 25 ± 1 °C and 12 h light/12 h darkness. On the 6th day length of stems and height of roots were measured. After doing statistical analysis, in low intensities of DC electric field, the highest significant increase of mean growth (The average of stem length and the height of roots) was seen in 1.5 kV/m in wet seeds. In high intensities of DC and AC electric fields, the highest significant increase of mean growth was seen in AC electric field of 100 kV/m in wet seeds.

  16. Socially optimal electric driving range of plug-in hybrid electric vehicles

    DOE PAGES

    Kontou, Eleftheria; Yin, Yafeng; Lin, Zhenhong

    2015-07-25

    Our study determines the optimal electric driving range of plug-in hybrid electric vehicles (PHEVs) that minimizes the daily cost borne by the society when using this technology. An optimization framework is developed and applied to datasets representing the US market. Results indicate that the optimal range is 16 miles with an average social cost of 3.19 per day when exclusively charging at home, compared to 3.27 per day of driving a conventional vehicle. The optimal range is found to be sensitive to the cost of battery packs and the price of gasoline. Moreover, when workplace charging is available, the optimalmore » electric driving range surprisingly increases from 16 to 22 miles, as larger batteries would allow drivers to better take advantage of the charging opportunities to achieve longer electrified travel distances, yielding social cost savings. If workplace charging is available, the optimal density is to deploy a workplace charger for every 3.66 vehicles. Finally, the diversification of the battery size, i.e., introducing a pair and triple of electric driving ranges to the market, could further decrease the average societal cost per PHEV by 7.45% and 11.5% respectively.« less

  17. Socially optimal electric driving range of plug-in hybrid electric vehicles

    SciTech Connect

    Kontou, Eleftheria; Yin, Yafeng; Lin, Zhenhong

    2015-07-25

    Our study determines the optimal electric driving range of plug-in hybrid electric vehicles (PHEVs) that minimizes the daily cost borne by the society when using this technology. An optimization framework is developed and applied to datasets representing the US market. Results indicate that the optimal range is 16 miles with an average social cost of 3.19 per day when exclusively charging at home, compared to 3.27 per day of driving a conventional vehicle. The optimal range is found to be sensitive to the cost of battery packs and the price of gasoline. Moreover, when workplace charging is available, the optimal electric driving range surprisingly increases from 16 to 22 miles, as larger batteries would allow drivers to better take advantage of the charging opportunities to achieve longer electrified travel distances, yielding social cost savings. If workplace charging is available, the optimal density is to deploy a workplace charger for every 3.66 vehicles. Finally, the diversification of the battery size, i.e., introducing a pair and triple of electric driving ranges to the market, could further decrease the average societal cost per PHEV by 7.45% and 11.5% respectively.

  18. Electric properties of carbon nano-onion/polyaniline composites: a combined electric modulus and ac conductivity study

    NASA Astrophysics Data System (ADS)

    Papathanassiou, Anthony N.; Mykhailiv, Olena; Echegoyen, Luis; Sakellis, Ilias; Plonska-Brzezinska, Marta E.

    2016-07-01

    The complex electric modulus and the ac conductivity of carbon nano-onion/polyaniline composites were studied from 1 mHz to 1 MHz at isothermal conditions ranging from 15 K to room temperature. The temperature dependence of the electric modulus and the dc conductivity analyses indicate a couple of hopping mechanisms. The distinction between thermally activated processes and the determination of cross-over temperature were achieved by exploring the temperature dependence of the fractional exponent of the dispersive ac conductivity and the bifurcation of the scaled ac conductivity isotherms. The results are analyzed by combining the granular metal model (inter-grain charge tunneling of extended electron states located within mesoscopic highly conducting polyaniline grains) and a 3D Mott variable range hopping model (phonon assisted tunneling within the carbon nano-onions and clusters).

  19. Simulational studies of epitaxial semiconductor superlattices: Quantum dynamical phenomena in ac and dc electric fields

    SciTech Connect

    Reynolds, J.

    1997-10-08

    Using high-accuracy numerical methods the author investigates the dynamics of independent electrons in both ideal and realistic superlattices subject to arbitrary ac and/or dc electric fields. For a variety of superlattice potentials, optically excited initial wave packets, and combinations of ac and dc electric fields, he numerically solves the time-dependent Schroedinger equation. In the case of ideal periodic superlattice potentials, he investigates a long list of dynamical phenomena involving multiple miniband transitions and time-dependent electric fields. These include acceleration effects associated with interminiband transitions in strong fields, Zener resonances between minibands, dynamic localization with ac fields, increased single-miniband transport with an auxiliary resonant ac field, and enhanced or suppressed interminiband probability exchange using an auxiliary ac field. For all of the cases studied, the resulting time-dependent wave function is analyzed by projecting the data onto convenient orthonormal bases. This allows a detailed comparison with approximately analytic treatments. In an effort to explain the rapid decay of experimentally measured Bloch oscillation (BO) signals the author incorporates a one-dimensional representation of interface roughness (IR) into their superlattice potential. He shows that as a result of IR, the electron dynamics can be characterized in terms of many discrete, incommensurate frequencies near the Block frequency. Chapters 2, 3, 4 and 5 have been removed from this report and will be processed separately.

  20. Evaluation of 2004 Toyota Prius Hybrid Electric Drive System

    SciTech Connect

    Staunton, Robert H; Ayers, Curtis William; Chiasson, J. N.; Burress, Timothy A; Marlino, Laura D

    2006-05-01

    The 2004 Toyota Prius is a hybrid automobile equipped with a gasoline engine and a battery- and generator-powered electric motor. Both of these motive-power sources are capable of providing mechanical-drive power for the vehicle. The engine can deliver a peak-power output of 57 kilowatts (kW) at 5000 revolutions per minute (rpm) while the motor can deliver a peak-power output of 50 kW over the speed range of 1200-1540 rpm. Together, this engine-motor combination has a specified peak-power output of 82 kW at a vehicle speed of 85 kilometers per hour (km/h). In operation, the 2004 Prius exhibits superior fuel economy compared to conventionally powered automobiles. To acquire knowledge and thereby improve understanding of the propulsion technology used in the 2004 Prius, a full range of design characterization studies were conducted to evaluate the electrical and mechanical characteristics of the 2004 Prius and its hybrid electric drive system. These characterization studies included (1) a design review, (2) a packaging and fabrication assessment, (3) bench-top electrical tests, (4) back-electromotive force (emf) and locked rotor tests, (5) loss tests, (6) thermal tests at elevated temperatures, and most recently (7) full-design-range performance testing in a controlled laboratory environment. This final test effectively mapped the electrical and thermal results for motor/inverter operation over the full range of speeds and shaft loads that these assemblies are designed for in the Prius vehicle operations. This testing was undertaken by the Oak Ridge National Laboratory (ORNL) as part of the U.S. Department of Energy (DOE) - Energy Efficiency and Renewable Energy (EERE) FreedomCAR and Vehicle Technologies (FCVT) program through its vehicle systems technologies subprogram. The thermal tests at elevated temperatures were conducted late in 2004, and this report does not discuss this testing in detail. The thermal tests explored the derating of the Prius motor design if

  1. Evaluation of 2004 Toyota Prius Hybrid Electric Drive System

    SciTech Connect

    Staunton, R.H.; Ayers, C.W.; Chiasson, J.N.; Burress, B.A.; Marlino, L.D.

    2006-05-01

    The 2004 Toyota Prius is a hybrid automobile equipped with a gasoline engine and a battery- and generator-powered electric motor. Both of these motive-power sources are capable of providing mechanical-drive power for the vehicle. The engine can deliver a peak-power output of 57 kilowatts (kW) at 5000 revolutions per minute (rpm) while the motor can deliver a peak-power output of 50 kW over the speed range of 1200-1540 rpm. Together, this engine-motor combination has a specified peak-power output of 82 kW at a vehicle speed of 85 kilometers per hour (km/h). In operation, the 2004 Prius exhibits superior fuel economy compared to conventionally powered automobiles. To acquire knowledge and thereby improve understanding of the propulsion technology used in the 2004 Prius, a full range of design characterization studies were conducted to evaluate the electrical and mechanical characteristics of the 2004 Prius and its hybrid electric drive system. These characterization studies included (1) a design review, (2) a packaging and fabrication assessment, (3) bench-top electrical tests, (4) back-electromotive force (emf) and locked rotor tests, (5) loss tests, (6) thermal tests at elevated temperatures, and most recently (7) full-design-range performance testing in a controlled laboratory environment. This final test effectively mapped the electrical and thermal results for motor/inverter operation over the full range of speeds and shaft loads that these assemblies are designed for in the Prius vehicle operations. This testing was undertaken by the Oak Ridge National Laboratory (ORNL) as part of the U.S. Department of Energy (DOE)-Energy Efficiency and Renewable Energy (EERE) FreedomCAR and Vehicle Technologies (FCVT) program through its vehicle systems technologies subprogram. The thermal tests at elevated temperatures were conducted late in 2004, and this report does not discuss this testing in detail. The thermal tests explored the derating of the Prius motor design if

  2. Highway vehicle electric drive in the United States : 2009 status and issues.

    SciTech Connect

    Santini, D. J.; Energy Systems

    2011-02-16

    The status of electric drive technology in the United States as of early 2010 is documented. Rapidly evolving electric drive technologies discussed include hybrid electric vehicles, multiple types of plug-in hybrid electric vehicles, and battery electric vehicles. Recent trends for hybrids are quantified. Various plug-in vehicles entering the market in the near term are examined. The technical and economic requirements for electric drive to more broadly succeed in a wider range of highway vehicle applications are described, and implications for the most promising new markets are provided. Federal and selected state government policy measures promoting and preparing for electric drive are discussed. Taking these into account, judgment on areas where increased Clean Cities funds might be most productively focused over the next five years are provided. In closing, the request by Clean Cities for opinion on the broad range of research needs providing near-term support to electric drive is fulfilled.

  3. Analytic formulation for the ac electrical conductivity in two- temperature, strongly coupled, overdense plasma: FORTRAN subroutine

    SciTech Connect

    Cauble, R.; Rozmus, W.

    1993-10-21

    A FORTRAN subroutine for the calculation of the ac electrical conductivity in two-temperature, strongly coupled, overdense plasma is presented. The routine is the result of a model calculation based on classical transport theory with application to plasmas created by the interaction of short pulse lasers and solids. The formulation is analytic and the routine is self-contained.

  4. Fuzzy Inference Based Obstacle Avoidance Control of Electric Powered Wheelchair Considering Driving Risk

    NASA Astrophysics Data System (ADS)

    Kiso, Atsushi; Murakami, Hiroki; Seki, Hirokazu

    This paper describes a novel obstacle avoidance control scheme of electric powered wheelchairs for realizing the safe driving in various environments. The “electric powered wheelchair” which generates the driving force by electric motors is expected to be widely used as a mobility support system for elderly people and disabled people; however, the driving performance must be further improved because the number of driving accidents caused by elderly operator's narrow sight and joystick operation errors is increasing. This paper proposes a novel obstacle avoidance control scheme based on fuzzy algorithm to prevent driving accidents. The proposed control system determines the driving direction by fuzzy algorithm based on the information of the joystick operation and distance to obstacles measured by ultrasonic sensors. Fuzzy rules to determine the driving direction are designed surely to avoid passers-by and walls considering the human's intent and driving environments. Some driving experiments on the practical situations show the effectiveness of the proposed control system.

  5. An optimization study on PEFC drive electric vehicle

    SciTech Connect

    Kishida, K.; Tanaka, M.; Kanai, K.

    1996-12-31

    Efforts have been made to develop fuel cell powered EVs (electric vehicles) in several countries and to demonstrate its high potential. Since 1990 fuel cell research has been conducted at FUT (the Fukui University of Technology) beginning with PAFC. Research effort is now being focused upon the application of fuel cells to the EV drive as this technology shows great future potential, particularly in the area concerning environmental protection. PEFC (Polymer Electrolyte Fuel Cell) has been chosen as the fuel cell for the EV power source because it possesses an inherent high power density and it also has another important feature; operation can be started under ambient temperature without preheating. The principal objective of this research is to pursue the optimum system of a PEFC drive EV. The size of the prototype vehicle in the university project is limited to a certain range and the capacity of the PEFG stack is also limited, for the time being anyway, as the PEFC technology is still under developmental stage in Japan. A 1.5 kW class PEFC stack has become available for the research at FUT by courtesy of a PEFC developer.

  6. Contact-Free Templating of 3-D Colloidal Structures Using Spatially Nonuniform AC Electric Fields.

    PubMed

    Raveendran, Joshua; Wood, Jeffery A; Docoslis, Aristides

    2016-09-20

    The formation of ordered and regularly shaped structures of colloidal particles with the aid of spatially nonuniform electric fields is a modern research area of great interest. This work illustrates how alternating current (AC) electrokinetic effects (dielectrophoresis, electroosmosis) can serve as contact-free templates, inside which colloidal microspheres can assemble into a variety of shapes and sizes. We show how three-dimensional colloidal structures of square, circular, and diamond shape of many tens of micrometers in size can be reproducibly formed with a single set of quadrupolar microelectrodes. Numerical simulations performed help to explain the role of AC electroosmosis and AC dielectrophoresis on the shaping of these structures as a function of applied voltage and frequency. We also demonstrate how the templating repertoire is further enhanced with the simultaneous application of a second, individually controlled AC electric field, which enables a variety of asymmetric colloidal structures to be produced using the same set of quadrupolar microelectrodes. As the preservation of shape and size of such electric-field templated structures after medium evaporation still remains a big challenge, here we also report on a novel method that permits the stabilization and isolation of these particle assemblies through medium gelation and subsequent hydrogel removal with a UV/ozone treatment.

  7. Contact-Free Templating of 3-D Colloidal Structures Using Spatially Nonuniform AC Electric Fields.

    PubMed

    Raveendran, Joshua; Wood, Jeffery A; Docoslis, Aristides

    2016-09-20

    The formation of ordered and regularly shaped structures of colloidal particles with the aid of spatially nonuniform electric fields is a modern research area of great interest. This work illustrates how alternating current (AC) electrokinetic effects (dielectrophoresis, electroosmosis) can serve as contact-free templates, inside which colloidal microspheres can assemble into a variety of shapes and sizes. We show how three-dimensional colloidal structures of square, circular, and diamond shape of many tens of micrometers in size can be reproducibly formed with a single set of quadrupolar microelectrodes. Numerical simulations performed help to explain the role of AC electroosmosis and AC dielectrophoresis on the shaping of these structures as a function of applied voltage and frequency. We also demonstrate how the templating repertoire is further enhanced with the simultaneous application of a second, individually controlled AC electric field, which enables a variety of asymmetric colloidal structures to be produced using the same set of quadrupolar microelectrodes. As the preservation of shape and size of such electric-field templated structures after medium evaporation still remains a big challenge, here we also report on a novel method that permits the stabilization and isolation of these particle assemblies through medium gelation and subsequent hydrogel removal with a UV/ozone treatment. PMID:27541583

  8. ac powertrain for an electric vehicle. Phase 2 and Phase 3 final report

    SciTech Connect

    Slicker, J.M.

    1984-11-01

    This report describes work relating to Phases 2 and 3 development and testing of an ac powertrain for a 25 hp four-passenger electric vehicle. The system, which consists of a two-speed automatic mechanical transaxle, 18.6 kW ac induction traction motor, 33.6 kW inverter and overall logic controller, was installed and evaluated in a converted Mercury Lynx rolling test bed vehicle. An on-board charger and an auxiliary dc-to-dc converter were integrated into the inverter/controller package.

  9. AC electric field induced droplet deformation in a microfluidic T-junction.

    PubMed

    Xi, Heng-Dong; Guo, Wei; Leniart, Michael; Chong, Zhuang Zhi; Tan, Say Hwa

    2016-08-01

    We present for the first time an experimental study on the droplet deformation induced by an AC electric field in droplet-based microfluidics. It is found that the deformation of the droplets becomes stronger with increasing electric field intensity and frequency. The measured electric field intensity dependence of the droplet deformation is consistent with an early theoretical prediction for stationary droplets. We also proposed a simple equivalent circuit model to account for the frequency dependence of the droplet deformation. The model well explains our experimental observations. In addition, we found that the droplets can be deformed repeatedly by applying an amplitude modulation (AM) signal. PMID:27173587

  10. Electromagnetic interference assessment of an ion drive electric propulsion system

    NASA Technical Reports Server (NTRS)

    Whittlesey, A. C.

    1979-01-01

    The electromagnetic interference (EMI) form elements of an ion drive electric propulsion system was analyzed, and the effects of EMI interaction with a typical interplanetary spacecraft engineering and scientific subsystems were predicted. SEMCAP, a computerized electromagnetic compatibility assessment code, was used to analyze the impact of EMI noise sources on 65 engineering/telemetry circuits and 48 plasma wave and planetary radio astronomy channels measuring over the range of 100 Hz to 40 MHz in a spacecraft of the Voyager type; manual methods were used to evaluate electrostatics, magnetics, and communications effects. Results indicate that some conducted and radiated spectra are in excess of electromagnetic compatibility specification limits; direct design changes may be required for filtering and shielding of thrust system elements. The worst source of broadband radiated noise appears to be the power processor. The magnetic field necessary to thruster operation is equivalent to about 18 amp-sq m per amp of beam current at right angles to the axis caused by the neutralizer/plume loop.

  11. Electro-worming: The behaviors of Caenorhabditis (C.) elegans in DC and AC electric fields

    NASA Astrophysics Data System (ADS)

    Chuang, Han-Sheng; Raizen, David M.; Dabbish, Nooreen; Bau, Haim H.

    2011-09-01

    The video showcases how C. elegans worms respond to DC and AC electrical stimulations. Gabel et al (2007) demonstrated that in the presence of DC and low frequency AC fields, worms of stage L2 and larger propel themselves towards the cathode. Rezai et al (2010) have demonstrated that this phenomenon, dubbed electrotaxis, can be used to control the motion of worms. In the video, we reproduce Rezai's experimental results. Furthermore, we show, for the first time, that worms can be trapped with high frequency, nonuniform electric fields. We studied the effect of the electric field on the nematode as a function of field intensity and frequency and identified a range of electric field intensities and frequencies that trap worms without apparent adverse effect on their viability. Worms tethered by dielectrophoresis (DEP) avoid blue light, indicating that at least some of the nervous system functions remain unimpaired in the presence of the electric field. DEP is useful to dynamically confine nematodes for observations, sort them according to size, and separate dead worms from live ones.

  12. AC electric field induced dipole-based on-chip 3D cell rotation.

    PubMed

    Benhal, Prateek; Chase, J Geoffrey; Gaynor, Paul; Oback, Björn; Wang, Wenhui

    2014-08-01

    The precise rotation of suspended cells is one of the many fundamental manipulations used in a wide range of biotechnological applications such as cell injection and enucleation in nuclear transfer (NT) cloning. Noticeably scarce among the existing rotation techniques is the three-dimensional (3D) rotation of cells on a single chip. Here we present an alternating current (ac) induced electric field-based biochip platform, which has an open-top sub-mm square chamber enclosed by four sidewall electrodes and two bottom electrodes, to achieve rotation about the two axes, thus 3D cell rotation. By applying an ac potential to the four sidewall electrodes, an in-plane (yaw) rotating electric field is generated and in-plane rotation is achieved. Similarly, by applying an ac potential to two opposite sidewall electrodes and the two bottom electrodes, an out-of-plane (pitch) rotating electric field is generated and rolling rotation is achieved. As a prompt proof-of-concept, bottom electrodes were constructed with transparent indium tin oxide (ITO) using the standard lift-off process and the sidewall electrodes were constructed using a low-cost micro-milling process and then assembled to form the chip. Through experiments, we demonstrate rotation of bovine oocytes of ~120 μm diameter about two axes, with the capability of controlling the rotation direction and the rate for each axis through control of the ac potential amplitude, frequency, and phase shift, and cell medium conductivity. The maximum observed rotation rate reached nearly 140° s⁻¹, while a consistent rotation rate reached up to 40° s⁻¹. Rotation rate spectra for zona pellucida-intact and zona pellucida-free oocytes were further compared and found to have no effective difference. This simple, transparent, cheap-to-manufacture, and open-top platform allows additional functional modules to be integrated to become a more powerful cell manipulation system.

  13. Novel Straight and Circular Road Driving Control of Electric Power Assisted Wheelchair Based on Fuzzy Algorithm

    NASA Astrophysics Data System (ADS)

    Seki, Hirokazu; Tadakuma, Susumu

    This paper describes a novel straight and circular road driving control scheme for electric power assisted wheelchairs. “Electric power assisted wheelchair” which assists the driving force by electric motors is expected to be widely used as a mobility support system for elderly people and disabled people, however, the performance of the straight and circular road driving must be further improved because the two wheels drive independently. This paper proposes a novel driving control scheme based on fuzzy algorithm to realize the stable and reliable driving on straight and circular roads. The suitable assisted torque of the right and left wheels is determined by fuzzy algorithm based on the posture angular velocity of the wheelchair and the human input torque proportion of the right and left wheels. Some experiments on the practical roads show the effectiveness of the proposed control system.

  14. Driving Control for Electric Power Assisted Wheelchair Based on Regenerative Brake

    NASA Astrophysics Data System (ADS)

    Seki, Hirokazu; Takahashi, Kazuki; Tadakuma, Susumu

    This paper describes a novel safety driving control scheme for electric power assisted wheelchairs based on the regenerative braking system. “Electric power assisted wheelchair” which assists the driving force by electric motors is expected to be widely used as a mobility support system for elderly people and disabled people, however, the safe and secure driving performance especially on downhill roads must be further improved because electric power assisted wheelchairs have no braking devices. The proposed control system automatically switches the driving mode, from “assisting mode” to “braking mode”, based on the wheelchair's velocity and the declined angle and smoothly suppresses the wheelchair's acceleration based on variable duty ratio control in order to realize the safety driving and to improve the ride quality. Some experiments on the practical roads and subjective evaluation show the effectiveness of the proposed control system.

  15. A high switching frequency IGBT PWM rectifier/inverter system for ac motor drives operating from single phase supply

    NASA Astrophysics Data System (ADS)

    Thiyagarajah, K.; Ranganathan, V. T.; Ramakrishna Iyengar, B. S.

    1991-10-01

    A pulse-width-modulated (PWM) rectifier/inverter system using insulated-gate-bipolar-transistors (IGBTs), capable of switching at 20 kHz is reported. The base drive circuit for the IGBT, incorporating short-circuit protection, is presented. The inverter uses an Undeland snubber together with a simple energy recovery circuit, which ensures reliable and efficient operation even for 20 kHz switching. The front end for the system is a regenerative single phase full-bridge IGBT inverter along with an ac reactor. Steady-state design considerations are explained, and control techniques for unity power factor operation and fast current control of the front end converter, in a rotating as well as a stationary reference frame, are discussed and compared. Results from computer simulations and experimental results for a 1.5-kW prototype system are presented.

  16. The ac and dc electric field meters developed for the US Department of Energy

    NASA Technical Reports Server (NTRS)

    Kirkham, H.; Johnston, A.; Jackson, S.; Sheu, K.

    1987-01-01

    Two space-potential electric field meters developed at the Jet Propulsion Laboratory under the auspices of the U.S. Department of Energy are described. One of the meters was designed to measure dc fields, the other ac fields. Both meters use fiber optics to couple a small measuring probe to a remote readout device, so as to minimize field perturbation due to the presence of the probe. By using coherent detection, it has been possible to produce instruments whose operating range extends from about 10 V/m up to about 2.5 kV/cm, without the need for range switching on the probe. The electrical and mechanical design of both meters are described in detail. Data from laboratory tests are presented, as well as the results of the tests at the National Bureau of Standards and the Electric Power Research Institute's High Voltage Transmission Research Facility.

  17. Characteristics of ac capillary discharge produced in electrically conductive water solution

    NASA Astrophysics Data System (ADS)

    DeBaerdemaeker, F.; Simek, M.; Schmidt, J.; Leys, C.

    2007-05-01

    Basic electrical, optical and calorimetric characteristics of an ac (50 Hz) driven capillary discharge produced in a water solution were studied for initial water solution conductivity in the range 50-1000 µS cm-1. Typical current and voltage waveforms and emission intensities produced by several electronically excited species were recorded with high time resolution. The evolution of the electrical current, power and capillary resistance was inspected during positive ac half-cycle for various operational regimes. A fast relaxation of the discharge following a breakdown event was observed. Optical measurements indicate that radiative species are mostly generated during the first few hundreds of nanoseconds of plasma generation and that the average duration of plasma emission induced by a discharge pulse is of the order of a few microseconds. Results of calorimetric measurements are in good agreement with average electrical measurements and support the assumption that the discharge is a constant source of heat delivered to the liquid. Assuming that only a fraction of the heat released inside the capillary can be transported by conduction through the capillary wall and via its orifices, the processes of bubble formation, expulsion and re-filling the capillary with 'fresh' water must play a key role in maintaining a thermal balance during long-time steady-state operation of the device. Furthermore, a simplified numerical model and a first order energy deposition calculation prove the plausibility of the bubble breakdown mechanism.

  18. Integrated Vehicle Thermal Management - Combining Fluid Loops in Electric Drive Vehicles (Presentation)

    SciTech Connect

    Rugh, J. P.

    2013-07-01

    Plug-in hybrid electric vehicles and electric vehicles have increased vehicle thermal management complexity, using separate coolant loop for advanced power electronics and electric motors. Additional thermal components result in higher costs. Multiple cooling loops lead to reduced range due to increased weight. Energy is required to meet thermal requirements. This presentation for the 2013 Annual Merit Review discusses integrated vehicle thermal management by combining fluid loops in electric drive vehicles.

  19. Advice and Hints in Training the Mentally Handicapped to Drive Electric Wheelchairs.

    ERIC Educational Resources Information Center

    Birath, Gunnar

    The booklet is intended to help train people with mild mental retardation to drive electric wheelchairs. The systematic training incorporates features of adequate time, stress upon generalization, and a relaxed and secure environment. Lessons are presented on the following skill areas: preparation, starting and stopping, driving straight ahead,…

  20. Modeling of Nanoparticle-Mediated Electric Field Enhancement Inside Biological Cells Exposed to AC Electric Fields

    NASA Astrophysics Data System (ADS)

    Tiwari, Pawan K.; Kang, Sung Kil; Kim, Gon Jun; Choi, Jun; Mohamed, A.-A. H.; Lee, Jae Koo

    2009-08-01

    We present in this article the effect of alternating electric field at kilohertz (kHz) and megahertz (MHz) frequencies on the biological cells in presence and absence of nanoparticles. The induced electric field strength distribution in the region around cell membrane and nucleus envelope display different behavior at kHz and MHz frequencies. The attachment of gold nanoparticles (GNPs), especially gold nanowires around the surface of nucleus induce enhanced electric field strengths. The induced field strengths are dependent on the length of nanowire and create varying field regions when the length of nanowire is increased from 2 to 4 µm. The varying nanowire length increased the induced field strengths inside nucleoplasm and region adjacent to the nucleus in the cytoplasm. We investigated a process of electrostatic disruption of nucleus membrane when the induced electric field strength across the nucleus exceeds its tensile strength.

  1. A multicylinder free-piston Stirling engine for application in Stirling-electric drive systems

    NASA Astrophysics Data System (ADS)

    de Graaff, Peter J.

    This study gives a short introduction to Stirling-electric drive systems and their applications. The development of a Stirling-electric drive system concentrates on the design of a free-piston Stirling engine (FPSE), which will form the most important part of the system. One of the most important ideas behind the design of the FPSE is that a simple, robust, and efficient electric power generator has to be developed which can run on any available liquid for gaseous fuel and which can easily be plugged into a larger system, such as a Stirling-electric drive system. The benefits are found mainly in the silent and environmentally friendly operation of the system, but also in the free positioning of the FPSE and the ease with which a mechanical connection can be made between the electric motor and the load.

  2. Effect of an AC electric field on the conductance of single-wall semiconductor-type carbon nanotubes

    SciTech Connect

    Belonenko, M. B.; Glazov, S. Yu.; Mescheryakova, N. E.

    2010-09-15

    The effect of an ac electric field on the conductance of a system of single-wall semiconductor-type carbon nanotubes placed in a dc electric field is considered. The strength vectors of dc and ac electric fields are directed along the nanotube axis. The electronic system of carbon nanotubes is considered in the context of the Boltzmann kinetic equation in the relaxation-time approximation. The dependence of the current density in the system on the characteristics of applied fields is studied. The effect of absolute negative conductance is detected.

  3. Comprehensive Analysis of Human Cells Motion under an Irrotational AC Electric Field in an Electro-Microfluidic Chip

    PubMed Central

    Kermarrec, Frédérique; Gidrol, Xavier; Peyrade, David

    2014-01-01

    AC electrokinetics is a versatile tool for contact-less manipulation or characterization of cells and has been widely used for separation based on genotype translation to electrical phenotypes. Cells responses to an AC electric field result in a complex combination of electrokinetic phenomena, mainly dielectrophoresis and electrohydrodynamic forces. Human cells behaviors to AC electrokinetics remain unclear over a large frequency spectrum as illustrated by the self-rotation effect observed recently. We here report and analyze human cells behaviors in different conditions of medium conductivity, electric field frequency and magnitude. We also observe the self-rotation of human cells, in the absence of a rotational electric field. Based on an analytical competitive model of electrokinetic forces, we propose an explanation of the cell self-rotation. These experimental results, coupled with our model, lead to the exploitation of the cell behaviors to measure the intrinsic dielectric properties of JURKAT, HEK and PC3 human cell lines. PMID:24736275

  4. An Impulse Electric Motor for Driving Recording Instruments

    NASA Technical Reports Server (NTRS)

    Joachim, W F

    1923-01-01

    The chief purpose in undertaking the development of this synchronous motor was the creation of a very small, compact power source, capable of driving the film drums of the recording aircraft instruments designed by the staff of the National Advisory Committee for Aeronautics.

  5. Standard and nonstandard nematic electrohydrodynamic convection in the presence of asymmetric ac electric fields

    NASA Astrophysics Data System (ADS)

    Low, Jonathan; Hogan, S. John

    2008-10-01

    In planar nematic electrohydrodynamic convection (EHC), a microscopic liquid crystal cell is driven by a homogeneous ac electric field, which, if strong enough, causes the fluid to destabilize into a regular pattern-forming state. We consider asymmetric electric fields E(t)=E(t+T)≠-E(t+T/2) , which leads to the possibility of three different types of instabilities at onset: conductive, dielectric, and subharmonic. The first two are already well known as they are easily produced when the system is driven by symmetric electric fields; the third can only occur when the electric field symmetry is broken. We present theoretical results on EHC using linear stability analysis and Floquet theory. We consider rigid and free boundary conditions, extending the model to two Fourier modes in the vertical plane, the inclusion of flexoelectricity, and using standard (nematic electric conductivity σa>0 and dielectric anisotorpy γa<0 ) and nonstandard (σa<0) material parameters. We make full use of a three-dimensional linear model where two mutually perpendicular planar wave numbers q and p can be varied. Our results show that there is a qualitative difference between the boundary conditions used, which is also dependent on how many vertical Fourier modes were used in the model. We have obtained threshold values favoring oblique rolls in subharmonic and dielectric regimes in parameter space. For the nonstandard EHC parameter values, both conduction and subharmonic regimes disappear and only the dielectric threshold exists.

  6. Offshore operations report. ESP - the electrical submersible pump. Part 7. Applying variable frequency drives to esps

    SciTech Connect

    Watson, A.J.

    1983-11-15

    The oil industry has begun using variable frequency drives on electric submersible pumps. In March 1983, there were approximately 350 variable frequency drives successfully operating on electrical submersible pumps throughout the world. Three types of variable frequency drives available are the current source inverter, the pulse width modulation, and the variable voltage source inverter. A short discussion of each type is given to explain why the variable voltage inverter is used most often in oil field applications and why it has been a success.

  7. The AC (Alternating Current) Electrical Behavior of Multi-layered Thermoelectric Devices

    NASA Astrophysics Data System (ADS)

    Alim, Mohammad A.; Budak, Satilmis; Bhattacharjee, Sudip

    2016-08-01

    In this study the ac (alternating current) small-signal electrical data in the frequency range 5 Hz ≤ f ≤ 13 MHz are obtained for the multi-layered thermoelectric (TE) devices to extract underlying operative mechanisms via an equivalent circuit model. This model is developed from the complex plane plots in conjunction with the Bode plot. It is observed that the inductive behavior is prevalent for both unbombarded and bombarded TE devices regardless of the doses as both types are observed as somewhat weak in thermoelectric properties. The bombarded multi-layered devices followed a systematic pattern in ac behavior via semicircular relaxation both in the impedance and admittance planes for the same measured data. This pattern is attributed to the transition from one lumped behavior to two distinct mechanisms. It is observed that the␣conductive nature of the equivalent circuit model via non-blocking (non-capacitive) elements, attributed to the underlying operative electrical paths between the two opposite electrodes across the multi-layered device exists, satisfying direct current conditions of the equivalent circuit model. The inductive behavior at high frequencies originates from the conductive aspect of the lumped response of the device in addition to the contribution of the electrode leads. Thus, the proposed equivalent circuit model contains external inductance that verifies a meaningful representation of the multi-layered TE device, though weak in thermoelectric properties.

  8. Combination of ac electroosmosis and dielectrophoresis for particle manipulation on electrically-induced microscale wave structures

    NASA Astrophysics Data System (ADS)

    Chung, Cheng-Che; Glawdel, Tomasz; Ren, Carolyn L.; Chang, Hsien-Chang

    2015-03-01

    This work presents a simple method to fabricate controllable microscale wave structures on the top of regular interdigitated electrode (IDE) arrays using electrically-assisted lithography techniques. Smooth wave structures are extremely difficult, if not impossible, to fabricate using traditional multilayer photolithography technology. The fabricated wave structures were carefully measured using an optical profiler and the measured wave profiles were used in the numerical simulation of electrical field and for evaluating the parameters influencing the fabricated wave structure. It is demonstrated that the combined smooth wave structure and IDE array offer unique capability for particle manipulation including particle concentration, aggregation and separation. Particle motion manipulated via the combined wave structure and IDE array is governed by ac electroosmosis (ACEO), dielectrophoresis (DEP) or a combination of both depending on the applied frequency. At lower frequencies (~30 kHz), ACEO dominates and particles are driven to move along the valleys of the wave structures; while at higher frequencies (~200 kHz), DEP force dominates which concentrates particles at the peaks of the wave structures. In addition, varying the ac waveform from sine-wave to square-wave allows for dynamic control of particle motion. Size-dependent particle separation over the wave structure is also demonstrated for a mixture of 0.5 µm and 2 µm particles that are separated into two populations by the joint effects of drag and DEP forces when being pumped to flow via ACEO.

  9. The AC (Alternating Current) Electrical Behavior of Multi-layered Thermoelectric Devices

    NASA Astrophysics Data System (ADS)

    Alim, Mohammad A.; Budak, Satilmis; Bhattacharjee, Sudip

    2016-11-01

    In this study the ac (alternating current) small-signal electrical data in the frequency range 5 Hz ≤ f ≤ 13 MHz are obtained for the multi-layered thermoelectric (TE) devices to extract underlying operative mechanisms via an equivalent circuit model. This model is developed from the complex plane plots in conjunction with the Bode plot. It is observed that the inductive behavior is prevalent for both unbombarded and bombarded TE devices regardless of the doses as both types are observed as somewhat weak in thermoelectric properties. The bombarded multi-layered devices followed a systematic pattern in ac behavior via semicircular relaxation both in the impedance and admittance planes for the same measured data. This pattern is attributed to the transition from one lumped behavior to two distinct mechanisms. It is observed that the conductive nature of the equivalent circuit model via non-blocking (non-capacitive) elements, attributed to the underlying operative electrical paths between the two opposite electrodes across the multi-layered device exists, satisfying direct current conditions of the equivalent circuit model. The inductive behavior at high frequencies originates from the conductive aspect of the lumped response of the device in addition to the contribution of the electrode leads. Thus, the proposed equivalent circuit model contains external inductance that verifies a meaningful representation of the multi-layered TE device, though weak in thermoelectric properties.

  10. CAD-CAE in Electrical Machines and Drives Teaching.

    ERIC Educational Resources Information Center

    Belmans, R.; Geysen, W.

    1988-01-01

    Describes the use of computer-aided design (CAD) techniques in teaching the design of electrical motors. Approaches described include three technical viewpoints, such as electromagnetics, thermal, and mechanical aspects. Provides three diagrams, a table, and conclusions. (YP)

  11. Extended cage adjustable speed electric motors and drive packages

    DOEpatents

    Hsu, John S.

    1999-01-01

    The rotor cage of a motor is extended, a second stator is coupled to this extended rotor cage, and the windings have the same number of poles. The motor torque and speed can be controlled by either injecting energy into or extracting energy out from the rotor cage. The motor produces less harmonics than existing doubly-fed motors. Consequently, a new type of low cost, high efficiency drive is produced.

  12. Extended cage adjustable speed electric motors and drive packages

    DOEpatents

    Hsu, J.S.

    1999-03-23

    The rotor cage of a motor is extended, a second stator is coupled to this extended rotor cage, and the windings have the same number of poles. The motor torque and speed can be controlled by either injecting energy into or extracting energy out from the rotor cage. The motor produces less harmonics than existing doubly-fed motors. Consequently, a new type of low cost, high efficiency drive is produced. 12 figs.

  13. Energy Characteristics of Electric Drive of Oscillatory Motion at the Shock-Free Start

    NASA Astrophysics Data System (ADS)

    Payuk, L. A.; Voronina, N. A.; Galtseva, O. V.

    2016-01-01

    The peculiarity of operation of oscillatory electric drive with doubly-fed motor at realization of algorithm of shock-free start was considered. The method of evaluating of energy parameters of such motors operating at the resonance mode with yueTOM of quantitative and qualitative components of the process of energy conversion by an electric motor (doubly-fed motor) is proposed. The calculation of energy characteristics of electric drive of this type was made, the results of calculation show an increase of energy efficiency (an average, generalized efficiency coefficient nE increased by 10%), which confirms the practical significance of the research object.

  14. Influence of AC and DC electrical stimulation on wound healing in pigs: a biomechanical analysis.

    PubMed

    Kambic, H E; Reyes, E; Manning, T; Waters, K C; Reger, S I

    1993-01-01

    To evaluate the effects of electrical stimulation on the mechanical properties of healing skin, 20 Hanford mini-pigs weighing 10-15 kg with trochanteric pressure ulcers were subjected to electrical stimulation. Examination of the biomechanical properties of the skin and changes in wound area and volume was done on previously wounded and healing pigskin subject to AC or DC electrical stimulation. The behavior of normal pigskin was compared to (1) denervated controls, (2) denervated AC-stimulated skin, and (3) denervated DC-stimulated skin. A denervated limb trochanteric pressure sore model developed in house permitted the use of a 6.5-mm percutaneous cancellous screw for wound formation and a 3-cm-diameter spring compression indentor to create reproducible and uniformly controlled grade 3 or higher tissue ulcers in the monoplegic hind limbs. Denervation was accomplished by right unilateral extradural rhizotomies from L2 to S1 nerve roots. Electrodes were placed 1 cm distal and proximal to the wound periphery, and wounds were stimulated 2 h/day, 5 days/week for 30 days. Dumbbell-shaped skin specimens with a length to width ratio of 3:1 were uniaxially loaded in tension until failure at an extension rate of 150 mm/min. The stiffness values for skin samples oriented parallel to the current flow were reduced by nearly half the values obtained for normal controls. Statistical differences (P < .05) were found for stress, Young modulus, and stiffness when compared to normal skin. Samples oriented in the perpendicular direction were comparable to normal skin (P = NS).(ABSTRACT TRUNCATED AT 250 WORDS)

  15. Road load simulator tests of the Gould phase 1 functional model silicon controlled rectifier ac motor controller for electric vehicles. Final Report

    SciTech Connect

    Gourash, F.

    1984-02-01

    The test results for a functional model ac motor controller for electric vehicles and a three-phase induction motor which were dynamically tested on the Lewis Research Center road load simulator are presented. Results show that the controller has the capability to meet the SAE-J227a D cycle test schedule and to accelerate a 1576-kg (3456-lb) simulated vehicle to a cruise speed of 88.5 km/hr (55 mph). Combined motor controller efficiency is 72 percent and the power inverter efficiency alone is 89 percent for the cruise region of the D cycle. Steady state test results for motoring, regeneration, and thermal data obtained by operating the simulator as a conventional dynamometer are in agreement with the contractor's previously reported data. The regeneration test results indicate that a reduction in energy requirements for urban driving cycles is attainable with regenerative braking. Test results and data in this report serve as a data base for further development of ac motor controllers and propulsion systems for electric vehicles. The controller uses state-of-the-art silicon controlled rectifier (SCR) power semiconductors and microprocessor-based logic and control circuitry. The controller was developed by Gould Laboratories under a Lewis contract for the Department of Energy's Electric and Hybrid Vehicle program.

  16. Influence of constant and ac electric fields on ferromagnetic resonance in magnetoelectric composites

    NASA Astrophysics Data System (ADS)

    Tatarenko, A. S.; Bichurin, M. I.; Petrov, V. M.; Fillipov, D. A.; Srinivasan, G.

    2004-03-01

    A composite of ferromagnetic and ferroelectric phases is expected to show magnetoelectric coupling that is mediated by mechanical deformation. For such composites, we proposed a model to treat the magnetoelectric (ME) coupling at frequencies corresponding to ferromagnetic resonance (FMR) [1,2]. The effect manifests as a shift in the resonance field when subjected to a constant electric field. Here we discuss a theory for the influence of both dc and high frequency electric fields on FMR in the composites. The model predicts a significant increase in the strength of ME coupling when the electric field is tuned to the electromechanical resonance (EMR) frequency. We assume the composite to be a homogeneous medium. By solving combined elastostatics, electrostatics and magnetostatics equations, we estimate the ME constants using effective parameters. The calculations are for 3-0, 0-3 and 2-2 connectivities. Expressions for ME coefficients are obtained as a function of interface coupling and the volume fraction for the piezoelectric phase. Under the influence of a constant electric field E, our model predicts a shift in the ferromagnetic resonance field that is proportional to ME constants. In the presence of an ac electric field, we estimate a strong ME coupling when the frequency is tuned to EMR. As an example, the FMR field shift at 9.3 GHz due an ac electrical field tuned to EMR at 350 kHz is determined for multilayer and bulk composites of nickel ferrite - lead zirconate titanate. It is shown that ME interactions are enhanced by several orders of magnitude compared to off resonance values. 1. M.I. Bichurin, I. A. Kornev, V. M. Petrov, A. S. Tatarenko, Yu. V. Kiliba, and G. Srinivasan. Phys. Rev. B 64, 094409 (2001). 2. M.I. Bichurin, V. M. Petrov, Yu. V. Kiliba, and G. Srinivasan. Phys. Rev. B 66, 134404 (2002). - supported by grants from the Russian Ministry of Education (Å02-3.4-278), the Universities of Russia Foundation (UNR 01.01.007), and the National Science

  17. Model-Based Analysis of Electric Drive Options for Medium-Duty Parcel Delivery Vehicles: Preprint

    SciTech Connect

    Barnitt, R. A.; Brooker, A. D.; Ramroth, L.

    2010-12-01

    Medium-duty vehicles are used in a broad array of fleet applications, including parcel delivery. These vehicles are excellent candidates for electric drive applications due to their transient-intensive duty cycles, operation in densely populated areas, and relatively high fuel consumption and emissions. The National Renewable Energy Laboratory (NREL) conducted a robust assessment of parcel delivery routes and completed a model-based techno-economic analysis of hybrid electric vehicle (HEV) and plug-in hybrid electric vehicle configurations. First, NREL characterized parcel delivery vehicle usage patterns, most notably daily distance driven and drive cycle intensity. Second, drive-cycle analysis results framed the selection of drive cycles used to test a parcel delivery HEV on a chassis dynamometer. Next, measured fuel consumption results were used to validate simulated fuel consumption values derived from a dynamic model of the parcel delivery vehicle. Finally, NREL swept a matrix of 120 component size, usage, and cost combinations to assess impacts on fuel consumption and vehicle cost. The results illustrated the dependency of component sizing on drive-cycle intensity and daily distance driven and may allow parcel delivery fleets to match the most appropriate electric drive vehicle to their fleet usage profile.

  18. Plasma Compression using Rotating Electric Fields - the Strong Drive Regime

    SciTech Connect

    Danielson, J. R.; Surko, C. M.

    2006-10-18

    The rotating wall technique has proven to be an excellent method to create high-density, single-component plasmas in Penning-Malmberg traps. It has become useful, and sometimes critical, for applications such as antihydrogen production and the tailoring of ion crystals and positron beams. Azimuthally phased rf fields apply a torque that injects angular momentum and produces radial plasma compression as it spins the plasma up. Recently, we discovered a new 'strong-drive' regime in which plasmas can be compressed until the E x B rotation frequency, fE (where fE {proportional_to} n, the plasma density) approaches the applied frequency, fRW. We review here highlights of a recently published study of this regime [Danielson, et al., Phys. Plasmas 13, 055706 (2006)]. Good compression is achieved over a broad range of RW frequencies without the need to tune to a plasma mode. Setting the plasma density can be done simply and reliably by tuning fRW. Characteristics of this strong-drive regime and the resulting high-density steady states are discussed.

  19. Study on A.C. electrical properties of pure and L-serine doped ADP crystals

    NASA Astrophysics Data System (ADS)

    Joshi, J. H.; Dixit, K. P.; Joshi, M. J.; Parikh, K. D.

    2016-05-01

    Ammonium Dihydrogen Phosphate (ADP) crystals have a wide range of applications in integrated and nonlinear optics. Amino acids having significant properties like molecular chirality, zwitter ionic nature, etc. attracted many researchers to dope them in various NLO crystals. In the present study, pure and different weight percentage L-serine doped ADP crystals were grown by slow solvent evaporation technique at room temperature. The A.C. electrical study was carried out for palletized samples at room temperature. The Nyquist plot showed two semi circles for pure ADP indicated the effect of grain and grain boundary, whereas the doped ADP samples exhibited the single semi circle suggesting the effect of grain. The values resistance and capacitance for grain and grain boundary were calculated. The effect of doping was clearly seen in the grain capacitance and resistance values. The dielectric constant and dielectric loss decreased with increase in frequency for all samples. The Jonscher power law was applied for A.C. conductivity for pure and doped ADP samples. The imaginary part of modulus and impedance versus frequency were drawn and the value of stretch exponent (β) was calculated for all the samples.

  20. Hall-Effect Based Semi-Fast AC On-Board Charging Equipment for Electric Vehicles

    PubMed Central

    Milanés-Montero, María Isabel; Gallardo-Lozano, Javier; Romero-Cadaval, Enrique; González-Romera, Eva

    2011-01-01

    The expected increase in the penetration of electric vehicles (EV) and plug-in hybrid electric vehicles (PHEV) will produce unbalanced conditions, reactive power consumption and current harmonics drawn by the battery charging equipment, causing a great impact on the power quality of the future smart grid. A single-phase semi-fast electric vehicle battery charger is proposed in this paper. This ac on-board charging equipment can operate in grid-to-vehicle (G2V) mode, and also in vehicle-to-grid (V2G) mode, transferring the battery energy to the grid when the vehicle is parked. The charger is controlled with a Perfect Harmonic Cancellation (PHC) strategy, contributing to improve the grid power quality, since the current demanded or injected has no harmonic content and a high power factor. Hall-effect current and voltage transducers have been used in the sensor stage to carry out this control strategy. Experimental results with a laboratory prototype are presented. PMID:22163697

  1. Hall-effect based semi-fast AC on-board charging equipment for electric vehicles.

    PubMed

    Milanés-Montero, María Isabel; Gallardo-Lozano, Javier; Romero-Cadaval, Enrique; González-Romera, Eva

    2011-01-01

    The expected increase in the penetration of electric vehicles (EV) and plug-in hybrid electric vehicles (PHEV) will produce unbalanced conditions, reactive power consumption and current harmonics drawn by the battery charging equipment, causing a great impact on the power quality of the future smart grid. A single-phase semi-fast electric vehicle battery charger is proposed in this paper. This ac on-board charging equipment can operate in grid-to-vehicle (G2V) mode, and also in vehicle-to-grid (V2G) mode, transferring the battery energy to the grid when the vehicle is parked. The charger is controlled with a Perfect Harmonic Cancellation (PHC) strategy, contributing to improve the grid power quality, since the current demanded or injected has no harmonic content and a high power factor. Hall-effect current and voltage transducers have been used in the sensor stage to carry out this control strategy. Experimental results with a laboratory prototype are presented.

  2. Evaluation of 2005 Honda Accord Hybrid Electric Drive System

    SciTech Connect

    Staunton, R.H.; Burress, T.A.; Marlino, L.D.

    2006-09-11

    The Hybrid Electric Vehicle (HEV) program officially began in 1993 as a five-year, cost-shared partnership between the U.S. Department of Energy (DOE) and American auto manufacturers: General Motors, Ford, and Daimler Chrysler. Currently, HEV research and development is conducted by DOE through its FreedomCAR and Vehicle Technologies (FCVT) program. The mission of the FCVT program is to develop more energy efficient and environmentally friendly highway transportation technologies. Program activities include research, development, demonstration, testing, technology validation, and technology transfer. These activities are aimed at developing technologies that can be domestically produced in a clean and cost-competitive manner. The vehicle systems technologies subprogram, which is one of four subprograms under the FCVT program, supports the efforts of the FreedomCAR through a three-phase approach [1] intended to: (1) Identify overall propulsion and vehicle-related needs by analyzing programmatic goals and reviewing industry's recommendations and requirements, then develop the appropriate technical targets for systems, subsystems, and component research and development activities; (2) Develop and validate individual subsystems and components, including electric motors, emission control devices, battery systems, power electronics, accessories, and devices to reduce parasitic losses; and (3) Determine how well the components and subassemblies work together in a vehicle environment or as a complete propulsion system and whether the efficiency and performance targets at the vehicle level have been achieved. The research performed under the vehicle systems subprogram will help remove technical and cost barriers to enable technology for use in such advanced vehicles as hybrid electric, plug-in electric, and fuel-cell-powered vehicles.

  3. Recovery Act - Sustainable Transportation: Advanced Electric Drive Vehicle Education Program

    SciTech Connect

    Caille, Gary

    2013-12-13

    The collective goals of this effort include: 1) reach all facets of this society with education regarding electric vehicles (EV) and plug–in hybrid electric vehicles (PHEV), 2) prepare a workforce to service these advanced vehicles, 3) create web–based learning at an unparalleled level, 4) educate secondary school students to prepare for their future and 5) train the next generation of professional engineers regarding electric vehicles. The Team provided an integrated approach combining secondary schools, community colleges, four–year colleges and community outreach to provide a consistent message (Figure 1). Colorado State University Ventures (CSUV), as the prime contractor, plays a key program management and co–ordination role. CSUV is an affiliate of Colorado State University (CSU) and is a separate 501(c)(3) company. The Team consists of CSUV acting as the prime contractor subcontracted to Arapahoe Community College (ACC), CSU, Motion Reality Inc. (MRI), Georgia Institute of Technology (Georgia Tech) and Ricardo. Collaborators are Douglas County Educational Foundation/School District and Gooru (www.goorulearning.org), a nonprofit web–based learning resource and Google spin–off.

  4. A Driving Behaviour Model of Electrical Wheelchair Users

    PubMed Central

    Hamam, Y.; Djouani, K.; Daachi, B.; Steyn, N.

    2016-01-01

    In spite of the presence of powered wheelchairs, some of the users still experience steering challenges and manoeuvring difficulties that limit their capacity of navigating effectively. For such users, steering support and assistive systems may be very necessary. To appreciate the assistance, there is need that the assistive control is adaptable to the user's steering behaviour. This paper contributes to wheelchair steering improvement by modelling the steering behaviour of powered wheelchair users, for integration into the control system. More precisely, the modelling is based on the improved Directed Potential Field (DPF) method for trajectory planning. The method has facilitated the formulation of a simple behaviour model that is also linear in parameters. To obtain the steering data for parameter identification, seven individuals participated in driving the wheelchair in different virtual worlds on the augmented platform. The obtained data facilitated the estimation of user parameters, using the ordinary least square method, with satisfactory regression analysis results. PMID:27148362

  5. A Driving Behaviour Model of Electrical Wheelchair Users.

    PubMed

    Onyango, S O; Hamam, Y; Djouani, K; Daachi, B; Steyn, N

    2016-01-01

    In spite of the presence of powered wheelchairs, some of the users still experience steering challenges and manoeuvring difficulties that limit their capacity of navigating effectively. For such users, steering support and assistive systems may be very necessary. To appreciate the assistance, there is need that the assistive control is adaptable to the user's steering behaviour. This paper contributes to wheelchair steering improvement by modelling the steering behaviour of powered wheelchair users, for integration into the control system. More precisely, the modelling is based on the improved Directed Potential Field (DPF) method for trajectory planning. The method has facilitated the formulation of a simple behaviour model that is also linear in parameters. To obtain the steering data for parameter identification, seven individuals participated in driving the wheelchair in different virtual worlds on the augmented platform. The obtained data facilitated the estimation of user parameters, using the ordinary least square method, with satisfactory regression analysis results. PMID:27148362

  6. Ac response of an electron gas under a strong electric-field bias

    SciTech Connect

    Ma, S. ); Shung, K.W. Solid State Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 )

    1993-10-15

    A linear ac response theory of an electron gas under a strong, static electric field ([bold E]) is presented, and applied to doped GaAs for a detailed calculation. This is a generalization of the force-balance transport equation developed by Ting [ital et] [ital al]., with which the nonlinear conductivity under a strong field can be studied. The dynamic screening effect is included in the theory and studied analytically. The result is expressed by a modified Drude formula, with an effective lifetime which is a function of the frequency and also of [bold E]---both its magnitude and its direction. The calculated optical reflectivity and absorption rate show anomalous structure at frequencies close to the plasmon oscillation, when the nonlinear dc effect due to a strong [bold E] is important. The anomaly is expected to be experimentally measurable.

  7. Downward Slope Driving Control for Electric Powered Wheelchair Based on Capacitor Regenerative Brake

    NASA Astrophysics Data System (ADS)

    Seki, Hirokazu; Takahashi, Yoshiaki

    This paper describes a novel capacitor regenerative braking control scheme of electric powered wheelchairs for efficient driving on downward slopes. An electric powered wheelchair, which generates the driving force by electric motors, is expected to be widely used as a mobility support system for elderly people and disabled people; however the energy efficiency has to be further improved because it is driven only by battery energy. This study proposes a capacitor regenerative braking circuit and two types of velocity control schemes with variable duty ratio. The proposed regenerative braking circuit is based on the step-up/down circuit with additional resistance and connects right and left motors in series in order to obtain a larger braking power. Some driving experiments on a practical downward slope show the effectiveness of the proposed control system.

  8. On the efficiency of electrical submersible pumps equipped with variable frequency drives: A field study

    SciTech Connect

    Patterson, M.M.

    1996-02-01

    A field study was conducted on 18 electrical-submersible-pump- (ESP-) equipped wells operating in the Williston basin. Fifteen of these wells were run with variable frequency drives (VFD`s). The purpose of the study was to determine the efficiency and operating characteristics of ESP`s operating with VFD`s and compare them to those without. Voltage, current, power, and frequency were measured at the drive input, the drive output, and ESP input. Production data were recorded and power and efficiency were calculated at all measurement locations and compared to published data.

  9. Analytic formulation for the ac electrical conductivity in two-temperature, strongly coupled, overdense plasma: FORTRAN subroutine

    NASA Astrophysics Data System (ADS)

    Cauble, R.; Rozmus, W.

    1993-10-01

    A FORTRAN subroutine for the calculation of the ac electrical conductivity in two-temperature, strongly coupled, overdense plasma is presented. The routine is the result of a model calculation based on classical transport theory with application to plasmas created by the interaction of short pulse lasers and solids. The formulation is analytic and the routine is self-contained.

  10. Viability and economics of building or purchasing, driving and maintaining an electric car

    SciTech Connect

    Tauber, L.A.

    1995-12-31

    This paper discusses the viability and economics of building or purchasing, driving and maintaining an electric car for commuting in the 90`s and beyond. Currently there are mandates in place that require that by the year 1998, two percent of the vehicles sold in California be {open_quotes}Zero Emission Vehicles{close_quotes} (ZEV). This same mandate has been imposed in many of the New England states as well. The {open_quotes}Big Three{close_quotes} automakers have answered with electric cars that surpass the $40,000 mark. What can the average person do, who wants to drive an electric car, but can`t afford these expensive prototypes? This paper will describe one approach to building an affordable electric car, with excellent performance and range. Additionally, there will be actual examples of these cars, using the design techniques outlined in this paper.

  11. Human aquaporin 4 gating dynamics in dc and ac electric fields: A molecular dynamics study

    NASA Astrophysics Data System (ADS)

    Garate, J.-A.; English, Niall J.; MacElroy, J. M. D.

    2011-02-01

    Water self-diffusion within human aquaporin 4 has been studied using molecular dynamics (MD) simulations in the absence and presence of external ac and dc electric fields. The computed diffusive (pd) and osmotic (pf) permeabilities under zero-field conditions are (0.718 ± 0.24) × 10-14 cm3 s-1 and (2.94 ± 0.47) × 10-14 cm3 s-1, respectively; our pf agrees with the experimental value of (1.50 ± 0.6) × 10-14 cm3 s-1. A gating mechanism has been proposed in which side-chain dynamics of residue H201, located in the selectivity filter, play an essential role. In addition, for nonequilibrium MD in external fields, it was found that water dipole orientation within the constriction region of the channel is affected by electric fields (e-fields) and that this governs the permeability. It was also found that the rate of side-chain flipping motion of residue H201 is increased in the presence of e-fields, which influences water conductivity further.

  12. From driving cycle analysis to understanding battery performance in real-life electric hybrid vehicle operation

    NASA Astrophysics Data System (ADS)

    Liaw, Bor Yann; Dubarry, Matthieu

    This paper proposes a methodology and approach to understand battery performance and life through driving cycle and duty cycle analyses from electric and hybrid vehicle (EHV) operation in real-world situations. Conducting driving cycle analysis with trip data collected from EHV operation in real life is very difficult and challenging. In fact, no comprehensive approach has been accepted to date, except those using standard driving cycles on a dynamometer or a track. Similarly, analyzing duty cycle performance of a battery under real-life operation faces the same challenge. A successful driving cycle analysis, however, can significantly enhance our understanding of EHV performance in real-life driving. Likewise, we also expect similar results through duty cycle analysis for batteries. Since 1995, we have been developing tools to analyze EHV and power source performance. In particular, we were able to collect data from a fleet of 15 Hyundai Santa Fe electric sports utility vehicles (e-SUVs) operated on Oahu, Hawaii; from July 2001 to June 2003 to allow driving and duty cycle analyses in order to understand battery pack performance from a variety of EHV operating conditions. We thus developed a comprehensive approach that comprises fuzzy logic pattern recognition (FL-PR) techniques to perform driving and duty cycle analyses. This approach has been successfully applied to EHV performance analysis via the creation of a compositional driving profile called "driving cycle profile" (DrCP) for each trip. The same approach was used to analyze battery performance via the construction of "duty cycle profile" (DuCP) to express battery usage under various operating conditions. The combination of the two analyses enables us to understand both the usage profile of EHV and battery performance in synergetic details and in a systematic manner using a pattern recognition technique.

  13. Optimizing and Diversifying Electric Vehicle Driving Range for U.S. Drivers

    SciTech Connect

    Lin, Zhenhong

    2014-08-11

    Properly determining the driving range is critical for accurately predicting the sales and social benefits of battery electric vehicles (BEVs). This study proposes a framework for optimizing the driving range by minimizing the sum of battery price, electricity cost, and range limitation cost referred to as the "range-related cost" as a measurement of range anxiety. The objective function is linked to policy-relevant parameters, including battery cost and price markup, battery utilization, charging infrastructure availability, vehicle efficiency, electricity and gasoline prices, household vehicle ownership, daily driving patterns, discount rate, and perceived vehicle lifetime. Qualitative discussion of the framework and its empirical application to a sample (N=36664) representing new car drivers in the United States is included. The quantitative results strongly suggest that ranges of less than 100 miles are likely to be more popular in the BEV market for a long period of time. The average optimal range among U.S. drivers is found to be largely inelastic. Still, battery cost reduction significantly drives BEV demand toward longer ranges, whereas improvement in the charging infrastructure is found to significantly drive BEV demand toward shorter ranges. In conclusion, the bias of a single-range assumption and the effects of range optimization and diversification in reducing such biases are both found to be significant.

  14. Optimizing and Diversifying Electric Vehicle Driving Range for U.S. Drivers

    DOE PAGES

    Lin, Zhenhong

    2014-08-11

    Properly determining the driving range is critical for accurately predicting the sales and social benefits of battery electric vehicles (BEVs). This study proposes a framework for optimizing the driving range by minimizing the sum of battery price, electricity cost, and range limitation cost referred to as the "range-related cost" as a measurement of range anxiety. The objective function is linked to policy-relevant parameters, including battery cost and price markup, battery utilization, charging infrastructure availability, vehicle efficiency, electricity and gasoline prices, household vehicle ownership, daily driving patterns, discount rate, and perceived vehicle lifetime. Qualitative discussion of the framework and its empiricalmore » application to a sample (N=36664) representing new car drivers in the United States is included. The quantitative results strongly suggest that ranges of less than 100 miles are likely to be more popular in the BEV market for a long period of time. The average optimal range among U.S. drivers is found to be largely inelastic. Still, battery cost reduction significantly drives BEV demand toward longer ranges, whereas improvement in the charging infrastructure is found to significantly drive BEV demand toward shorter ranges. In conclusion, the bias of a single-range assumption and the effects of range optimization and diversification in reducing such biases are both found to be significant.« less

  15. Sub-micrometer particles produced by a low-powered AC electric arc in liquids.

    PubMed

    Jaworski, Jacek A; Fleury, Eric

    2012-01-01

    The article presents the report of the production of composites of sub-micrometer metal particles in matrix consisted of the metal compounds by means of an AC electric arc in water and paraffin solutions using electrodes carbon-metal and metal-metal (metal: Ni, Fe, Co, Cu). The advantage of this method is the low electric power (from 5 to 10 W) needed in comparison to standard DC arc-discharge methods (0.8 to 3 kW). This method enables the production of particles from conductive material also in wide range of temperature and in solvent which could be either transparent to light or opaque. Moreover the solvent can be electrolyte or insulating liquid. The microstructure of the composite layer was investigated by scanning electron microscopy (SEM), Electron Probe Microanalysis (EPMA) and X-ray. During particles production in water metal oxides were created. Additionally using cobalt-copper, nickel-copper as couple electrodes, insoluble in water copper (II) hydroxide crystal grains were created additionally which crystals shape was depended on transition metal. For iron-copper couple electrodes system the copper (II) hydroxide was not formed. Experiments with sequence production of Ni and Fe particles with C electrode assisting in molten paraffin let to obtain both Ni and Fe particles surrounded by paraffin. After solidification the material was insulator but if locally magnetic field influenced on the liquid solution in that place after solidification a new composite was created which was electric current conductor with resistivity around 0.1 omega x m, was attracted by magnetic field and presented magneto resistance around 0.4% in changing magnetic field in a range 150 mT. After mixing the concentrated paraffin with normal paraffin resistivity of the mixture increased and it became photosensitive and created small voltage under light influence. PMID:22524027

  16. DETAIL OF GENERAL ELECTRIC 250HP SYNCHRONOUS MOTOR FROM DRIVE END. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DETAIL OF GENERAL ELECTRIC 250-HP SYNCHRONOUS MOTOR FROM DRIVE END. MOTOR BADGE PLATE READS 263 AMP, 400 VOLT, FRAME 6274-D #4940649, 250 HORSEPOWER, TYPE TSR, 3 PHASE, 60 CYCLE, SPEED 300 RPM. - Shenandoah-Dives Mill, 135 County Road 2, Silverton, San Juan County, CO

  17. Low speed, long term tracking electric drive system has zero backlash

    NASA Technical Reports Server (NTRS)

    Richter, H. L.; Stoller, F. W.

    1967-01-01

    Electric drive system provides low speed, long term tracking of targets that move at a sidereal rate. It utilizes eddy-current energized actuators that are free from radio frequency interference generation and a solid state feedback amplifier with provisions for antibacklash biasing.

  18. Comparison of Plug-In Hybrid Electric Vehicle Battery Life Across Geographies and Drive-Cycles

    SciTech Connect

    Smith, K.; Warleywine, M.; Wood, E.; Neubauer, J.; Pesaran, A.

    2012-06-01

    In a laboratory environment, it is cost prohibitive to run automotive battery aging experiments across a wide range of possible ambient environment, drive cycle and charging scenarios. Since worst-case scenarios drive the conservative sizing of electric-drive vehicle batteries, it is useful to understand how and why those scenarios arise and what design or control actions might be taken to mitigate them. In an effort to explore this problem, this paper applies a semi-empirical life model of the graphite/nickel-cobalt-aluminum lithium-ion chemistry to investigate impacts of geographic environments under storage and simplified cycling conditions. The model is then applied to analyze complex cycling conditions, using battery charge/discharge profiles generated from simulations of PHEV10 and PHEV40 vehicles across 782 single-day driving cycles taken from Texas travel survey data.

  19. A traction control strategy with an efficiency model in a distributed driving electric vehicle.

    PubMed

    Lin, Cheng; Cheng, Xingqun

    2014-01-01

    Both active safety and fuel economy are important issues for vehicles. This paper focuses on a traction control strategy with an efficiency model in a distributed driving electric vehicle. In emergency situation, a sliding mode control algorithm was employed to achieve antislip control through keeping the wheels' slip ratios below 20%. For general longitudinal driving cases, an efficiency model aiming at improving the fuel economy was built through an offline optimization stream within the two-dimensional design space composed of the acceleration pedal signal and the vehicle speed. The sliding mode control strategy for the joint roads and the efficiency model for the typical drive cycles were simulated. Simulation results show that the proposed driving control approach has the potential to apply to different road surfaces. It keeps the wheels' slip ratios within the stable zone and improves the fuel economy on the premise of tracking the driver's intention. PMID:25197697

  20. A traction control strategy with an efficiency model in a distributed driving electric vehicle.

    PubMed

    Lin, Cheng; Cheng, Xingqun

    2014-01-01

    Both active safety and fuel economy are important issues for vehicles. This paper focuses on a traction control strategy with an efficiency model in a distributed driving electric vehicle. In emergency situation, a sliding mode control algorithm was employed to achieve antislip control through keeping the wheels' slip ratios below 20%. For general longitudinal driving cases, an efficiency model aiming at improving the fuel economy was built through an offline optimization stream within the two-dimensional design space composed of the acceleration pedal signal and the vehicle speed. The sliding mode control strategy for the joint roads and the efficiency model for the typical drive cycles were simulated. Simulation results show that the proposed driving control approach has the potential to apply to different road surfaces. It keeps the wheels' slip ratios within the stable zone and improves the fuel economy on the premise of tracking the driver's intention.

  1. A Traction Control Strategy with an Efficiency Model in a Distributed Driving Electric Vehicle

    PubMed Central

    Lin, Cheng

    2014-01-01

    Both active safety and fuel economy are important issues for vehicles. This paper focuses on a traction control strategy with an efficiency model in a distributed driving electric vehicle. In emergency situation, a sliding mode control algorithm was employed to achieve antislip control through keeping the wheels' slip ratios below 20%. For general longitudinal driving cases, an efficiency model aiming at improving the fuel economy was built through an offline optimization stream within the two-dimensional design space composed of the acceleration pedal signal and the vehicle speed. The sliding mode control strategy for the joint roads and the efficiency model for the typical drive cycles were simulated. Simulation results show that the proposed driving control approach has the potential to apply to different road surfaces. It keeps the wheels' slip ratios within the stable zone and improves the fuel economy on the premise of tracking the driver's intention. PMID:25197697

  2. Electron-radiation effects on the ac and dc electrical properties and unpaired electron densities of three aerospace polymers

    NASA Technical Reports Server (NTRS)

    Long, Sheila Ann T.; Long, Edward R., Jr.; Ries, Heidi R.; Harries, Wynford L.

    1986-01-01

    The effects of gigarad-level total absorbed doses from 1-MeV electrons on the post-irradiation alternating-current (ac) and direct-current (dc) electrical properties and the unpaired electron densities have been studied for Kapton, Ultem, and Mylar. The unpaired electron densities (determined from electron paramagnetic resonance spectroscopy) and the dc electrical conductivities of the irradiated materials were monitored as functions of time following the exposures to determine their decay characteristics at room temperature. The elevated-temperature ac electrical dissipations of the Ultem and Mylar were affected by the radiation. The dc conductivity of the Kapton increased by five orders of magnitude, while the dc conductivities of the Ultem and Mylar increased by less than an order of magnitude, due to the radiation. The observed radiation-generated changes in the ac electrical dissipations are explained in terms of known radiation-generated changes in the molecular structures of the three materials. A preliminary model relating the dc electrical conductivity and the unpaired electron density in the Kapton is proposed.

  3. Evaluation of semiconductor devices for Electric and Hybrid Vehicle (EHV) ac-drive applications, volume 2

    NASA Technical Reports Server (NTRS)

    Lee, F. C.; Chen, D. Y.; Jovanic, M.; Hopkins, D. C.

    1985-01-01

    Test data of switching times characterization of bipolar transistors, of field effect transistor's switching times on-resistance and characterization, comparative data of field effect transistors, and test data of field effect transistor's parallel operation characterization are given. Data is given in the form of graphs.

  4. Thermal Management of Power Electronics and Electric Motors for Electric-Drive Vehicles (Presentation)

    SciTech Connect

    Narumanchi, S.

    2014-09-01

    This presentation is an overview of the power electronics and electric motor thermal management and reliability activities at NREL. The focus is on activities funded by the Department of Energy Vehicle Technologies Office Advanced Power Electronics and Electric Motors Program.

  5. Response Surface Energy Modeling of an Electric Vehicle over a Reduced Composite Drive Cycle

    SciTech Connect

    Jehlik, Forrest; LaClair, Tim J.

    2014-04-01

    Response surface methodology (RSM) techniques were applied to develop a predictive model of electric vehicle (EV) energy consumption over the Environmental Protection Agency's (EPA) standardized drive cycles. The model is based on measurements from a synthetic composite drive cycle. The synthetic drive cycle is a minimized statistical composite of the standardized urban (UDDS), highway (HWFET), and US06 cycles. The composite synthetic drive cycle is 20 minutes in length thereby reducing testing time of the three standard EPA cycles by over 55%. Vehicle speed and acceleration were used as model inputs for a third order least squared regression model predicting vehicle battery power output as a function of the drive cycle. The approach reduced three cycles and 46 minutes of drive time to a single test of 20 minutes. Application of response surface modeling to the synthetic drive cycle is shown to predict energy consumption of the three EPA cycles within 2.6% of the actual measured values. Additionally, the response model may be used to predict energy consumption of any cycle within the speed/acceleration envelope of the synthetic cycle. This technique results in reducing test time, which additionally provides a model that may be used to expand the analysis and understanding of the vehicle under consideration.

  6. Frequency and voltage dependent profile of dielectric properties, electric modulus and ac electrical conductivity in the PrBaCoO nanofiber capacitors

    NASA Astrophysics Data System (ADS)

    Demirezen, S.; Kaya, A.; Yerişkin, S. A.; Balbaşı, M.; Uslu, İ.

    In this study, praseodymium barium cobalt oxide nanofiber interfacial layer was sandwiched between Au and n-Si. Frequency and voltage dependence of ε‧, ε‧, tanδ, electric modulus (M‧ and M″) and σac of PrBaCoO nanofiber capacitor have been investigated by using impedance spectroscopy method. The obtained experimental results show that the values of ε‧, ε‧, tanδ, M‧, M″ and σac of the PrBaCoO nanofiber capacitor are strongly dependent on frequency of applied bias voltage. The values of ε‧, ε″ and tanδ show a steep decrease with increasing frequency for each forward bias voltage, whereas the values of σac and the electric modulus increase with increasing frequency. The high dispersion in ε‧ and ε″ values at low frequencies may be attributed to the Maxwell-Wagner and space charge polarization. The high values of ε‧ may be due to the interfacial effects within the material, PrBaCoO nanofibers interfacial layer and electron effect. The values of M‧ and M″ reach a maximum constant value corresponding to M∞ ≈ 1/ε∞ due to the relaxation process at high frequencies, but both the values of M‧ and M″ approach almost to zero at low frequencies. The changes in the dielectric and electrical properties with frequency can be also attributed to the existence of Nss and Rs of the capacitors. As a result, the change in the ε‧, ε″, tanδ, M‧, M″ and ac electric conductivity (σac) is a result of restructuring and reordering of charges at the PrBaCoO/n-Si interface under an external electric field or voltage and interface polarization.

  7. Performance criteria guideline for three explosion protection methods of electrical equipment rated up to 15,000 volts AC

    NASA Astrophysics Data System (ADS)

    Linley, L. J.; Luper, A. B.; Dunn, J. H.

    1982-12-01

    The Bureau of Mines, U.S. Department of the Interior, is reviewing explosion protection methods for use in gassy coal mines. This performance criteria guideline is an evaluation of three explosion protection methods of machines electrically powered with voltages up to 15,000 volts ac. A sufficient amount of basic research has been accomplished to verify that the explosion proof and pressurized enclosure methods can provide adequate explosion protection with the present state of the art up to 15,000 volts ac. This routine application of the potted enclosure as a stand alone protection method requires further investigation or development in order to clarify performance criteria and verification certification requirements. An extensive literature search, a series of high voltage tests, and a design evaluation of the three explosion protection methods indicate that the explosion proof, pressurized, and potted enclosures can all be used to enclose up to 15,000 volts ac.

  8. Performance criteria guideline for three explosion protection methods of electrical equipment rated up to 15,000 volts AC

    NASA Technical Reports Server (NTRS)

    Linley, L. J.; Luper, A. B.; Dunn, J. H.

    1982-01-01

    The Bureau of Mines, U.S. Department of the Interior, is reviewing explosion protection methods for use in gassy coal mines. This performance criteria guideline is an evaluation of three explosion protection methods of machines electrically powered with voltages up to 15,000 volts ac. A sufficient amount of basic research has been accomplished to verify that the explosion proof and pressurized enclosure methods can provide adequate explosion protection with the present state of the art up to 15,000 volts ac. This routine application of the potted enclosure as a stand alone protection method requires further investigation or development in order to clarify performance criteria and verification certification requirements. An extensive literature search, a series of high voltage tests, and a design evaluation of the three explosion protection methods indicate that the explosion proof, pressurized, and potted enclosures can all be used to enclose up to 15,000 volts ac.

  9. Mesoscopic turbulence and local order in Janus particles self-propelling under an ac electric field.

    PubMed

    Nishiguchi, Daiki; Sano, Masaki

    2015-11-01

    To elucidate mechanisms of mesoscopic turbulence exhibited by active particles, we experimentally study turbulent states of nonliving self-propelled particles. We realize an experimental system with dense suspensions of asymmetrical colloidal particles (Janus particles) self-propelling on a two-dimensional surface under an ac electric field. Velocity fields of the Janus particles in the crowded situation can be regarded as a sort of turbulence because it contains many vortices and their velocities change abruptly. Correlation functions of their velocity field reveal the coexistence of polar alignment and antiparallel alignment interactions, which is considered to trigger mesoscopic turbulence. Probability distributions of local order parameters for polar and nematic orders indicate the formation of local clusters with particles moving in the same direction. A broad peak in the energy spectrum of the velocity field appears at the spatial scales where the polar alignment and the cluster formation are observed. Energy is injected at the particle scale and conserved quantities such as energy could be cascading toward the larger clusters. PMID:26651697

  10. Mesoscopic turbulence and local order in Janus particles self-propelling under an ac electric field

    NASA Astrophysics Data System (ADS)

    Nishiguchi, Daiki; Sano, Masaki

    2015-11-01

    To elucidate mechanisms of mesoscopic turbulence exhibited by active particles, we experimentally study turbulent states of nonliving self-propelled particles. We realize an experimental system with dense suspensions of asymmetrical colloidal particles (Janus particles) self-propelling on a two-dimensional surface under an ac electric field. Velocity fields of the Janus particles in the crowded situation can be regarded as a sort of turbulence because it contains many vortices and their velocities change abruptly. Correlation functions of their velocity field reveal the coexistence of polar alignment and antiparallel alignment interactions, which is considered to trigger mesoscopic turbulence. Probability distributions of local order parameters for polar and nematic orders indicate the formation of local clusters with particles moving in the same direction. A broad peak in the energy spectrum of the velocity field appears at the spatial scales where the polar alignment and the cluster formation are observed. Energy is injected at the particle scale and conserved quantities such as energy could be cascading toward the larger clusters.

  11. Elimination of harmonic induced viable bifurcations with TCSC for ac-fed electric arc furnaces

    NASA Astrophysics Data System (ADS)

    Varan, Metin; Uyarog˜lu, Yılmaz

    2012-11-01

    AC-fed electric arc furnaces (EAFs) are known with their unbalanced, excessively nonlinear and time varying load characteristics. The nonlinear oscillations produced by EAF operation cause several problems to interconnected feed system. Injection of harmonics/interharmonics and rising flicker effects on the feed system are two of major problems produced by EAF. These nonlinear effects result into quasistatic changes in the feed system parameters (L - R) . In last decade many studies have been reported that such quasistatic changes in the feed system parameters result in viable bifurcation formations which strictly cause sudden and drastic changes on system behaviors. This paper presents an analytical control procedure to eliminate viable bifurcation points on L - I and R - I curves that cause sudden resonant peak arc currents. After control procedure, stability margins of EAF are extended into larger levels and viable bifurcation points on the feed system parameter have been eliminated. During study, possible roles of small parameter changes of uncontrolled EAF around bifurcation points and controlled EAF have been traced over time series analysis, phase plane analysis and bifurcation diagrams. A wide collection of useful dynamic analysis procedures for the exploration of studied arc furnace dynamics have been handled through the AUTO open-source algorithms.

  12. Fuel-Cell-Powered Electric Motor Drive Analyzed for a Large Airplane

    NASA Technical Reports Server (NTRS)

    Brown, Gerald V.; Choi, Benjamin B.

    2005-01-01

    Because of its high efficiency, fuel cell technology may be used to launch a new generation of more-electric aeropropulsion and power systems for future aircraft. Electric-motor-driven airplanes using fuel-cell powerplants would be beneficial to the environment because of fuel savings, low noise, and zero carbon-dioxide emissions. In spite of the fuel cell s efficiency benefit, to produce the same shaft drive power, a fuel cell- powered electric-drive system must be definitely heavier than a turbine-drive system. However, the fuel-cell system s overall efficiency from fuel-to-shaft power is higher than for a turbine-drive system. This means that the fuel consumption rate could be lower than for a conventional system. For heavier, fuel-laden planes for longer flights, we might achieve substantial fuel savings. In the airplane industry, in fact, an efficiency gain of even a few percentage points can make a major economic difference in operating costs.

  13. Advanced single permanent magnet axipolar ironless stator ac motor for electric passenger vehicles

    NASA Technical Reports Server (NTRS)

    Beauchamp, E. D.; Hadfield, J. R.; Wuertz, K. L.

    1983-01-01

    A program was conducted to design and develop an advanced-concept motor specifically created for propulsion of electric vehicles with increased range, reduced energy consumption, and reduced life-cycle costs in comparison with conventional systems. The motor developed is a brushless, dc, rare-earth cobalt, permanent magnet, axial air gap inductor machine that uses an ironless stator. Air cooling is inherent provided by the centrifugal-fan action of the rotor poles. An extensive design phase was conducted, which included analysis of the system performance versus the SAE J227a(D) driving cycle. A proof-of-principle model was developed and tested, and a functional model was developed and tested. Full generator-level testing was conducted on the functional model, recording electromagnetic, thermal, aerodynamic, and acoustic noise data. The machine demonstrated 20.3 kW output at 1466 rad/s and 160 dc. The novel ironless stator demonstated the capability to continuously operate at peak current. The projected system performance based on the use of a transistor inverter is 23.6 kW output power at 1466 rad/s and 83.3 percent efficiency. Design areas of concern regarding electric vehicle applications include the inherently high windage loss and rotor inertia.

  14. Controller for controlling operation of at least one electrical load operating on an AC supply, and a method thereof

    DOEpatents

    Cantin, Luc; Deschenes, Mario; D'Amours, Mario

    1995-08-15

    A controller is provided for controlling operation of at least one electrical load operating on an AC supply having a typical frequency, the AC supply being provided via power transformers by an electrical power distribution grid. The controller is associated with the load and comprises an input interface for coupling the controller to the grid, a frequency detector for detecting the frequency of the AC supply and producing a signal indicative of the frequency, memory modules for storing preprogrammed commands, a frequency monitor for reading the signal indicative of the frequency and producing frequency data derived thereof, a selector for selecting at least one of the preprogrammed commands with respect to the frequency data, a control unit for producing at least one command signal representative of the selected preprogrammed commands, and an output interface including a device responsive to the command signal for controlling the load. Therefore, the load can be controlled by means of the controller depending on the frequency of the AC supply.

  15. Driving modes for designing the cornering response of fully electric vehicles with multiple motors

    NASA Astrophysics Data System (ADS)

    De Novellis, Leonardo; Sorniotti, Aldo; Gruber, Patrick

    2015-12-01

    Fully electric vehicles with multiple drivetrains allow a significant variation of the steady-state and transient cornering responses through the individual control of the electric motor drives. As a consequence, alternative driving modes can be created that provide the driver the option to select the preferred dynamic vehicle behavior. This article presents a torque-vectoring control structure based on the combination of feedforward and feedback contributions for the continuous control of vehicle yaw rate. The controller is specifically developed to be easily implementable on real-world vehicles. A novel model-based procedure for the definition of the control objectives is described in detail, together with the automated tuning process of the algorithm. The implemented control functions are demonstrated with experimental vehicle tests. The results show the possibilities of torque-vectoring control in designing the vehicle understeer characteristic.

  16. Characterization, performance, and prediction of a lead-acid battery under simulated electric vehicle driving requirements

    NASA Technical Reports Server (NTRS)

    Ewashinka, J. G.; Bozek, J. M.

    1981-01-01

    A state-of-the-art 6-V battery module in current use by the electric vehicle industry was tested at the NASA Lewis Research Center to determine its performance characteristics under the SAE J227a driving schedules B, C, and D. The primary objective of the tests was to determine the effects of periods of recuperation and long and short periods of electrical regeneration in improving the performance of the battery module and hence extendng the vehicle range. A secondary objective was to formulate a computer program that would predict the performance of this battery module for the above driving schedules. The results show excellent correlation between the laboratory tests and predicted results. The predicted performance compared with laboratory tests was within +2.4 to -3.7 percent for the D schedule, +0.5 to -7.1 percent for the C schedule, and better than -11.4 percent for the B schedule.

  17. Scientific Laboratory Platform for Testing the Electric Vehicle Equipped with DC Drive

    NASA Astrophysics Data System (ADS)

    Brazis, V.; Kroics, K.; Grigans, L.

    2014-12-01

    The authors present a test platform for the low-power DC electric motor of a traction vehicle or a high-power motor scaled in the traction and braking modes. The load emulator of the traction drive is made using an induction motor controlled by a frequency converter. A microcontroller controls the bi-directional DC/DC converter and sends a speed reference signal to the frequency converter. The test bench is meant for determination of the power consumption by motor in various speed cycles, and will be used to demonstrate the operation of electric vehicle to students and to investigate the charging/discharging strategies of energy sources.

  18. Statistical Characterization of Medium-Duty Electric Vehicle Drive Cycles; NREL (National Renewable Energy Laboratory)

    SciTech Connect

    Prohaska, R.; Duran, A.; Ragatz, A.; Kelly, K.

    2015-05-03

    With funding from the U.S. Department of Energy’s Vehicle Technologies Office, the National Renewable Energy Laboratory (NREL) conducts real-world performance evaluations of advanced medium- and heavy-duty fleet vehicles. Evaluation results can help vehicle manufacturers fine-tune their designs and assist fleet managers in selecting fuel-efficient, low-emission vehicles that meet their economic and operational goals. In 2011, NREL launched a large-scale performance evaluation of medium-duty electric vehicles. With support from vehicle manufacturers Smith and Navistar, NREL research focused on characterizing vehicle operation and drive cycles for electric delivery vehicles operating in commercial service across the nation.

  19. Implications of driving patterns on well-to-wheel performance of plug-in hybrid electric vehicles.

    PubMed

    Raykin, Leon; MacLean, Heather L; Roorda, Matthew J

    2012-06-01

    This study examines how driving patterns (distance and conditions) and the electricity generation supply interact to impact well-to-wheel (WTW) energy use and greenhouse gas (GHG) emissions of plug-in hybrid electric vehicles (PHEVs). The WTW performance of a PHEV is compared with that of a similar (nonplug-in) gasoline hybrid electric vehicle and internal combustion engine vehicle (ICEV). Driving PHEVs for short distances between recharging generally results in lower WTW total and fossil energy use and GHG emissions per kilometer compared to driving long distances, but the extent of the reductions depends on the electricity supply. For example, the shortest driving pattern in this study with hydroelectricity uses 81% less fossil energy than the longest driving pattern. However, the shortest driving pattern with coal-based electricity uses only 28% less fossil energy. Similar trends are observed in reductions relative to the nonplug-in vehicles. Irrespective of the electricity supply, PHEVs result in greater reductions in WTW energy use and GHG emissions relative to ICEVs for city than highway driving conditions. PHEVs charging from coal facilities only reduce WTW energy use and GHG emissions relative to ICEVs for certain favorable driving conditions. The study results have implications for environmentally beneficial PHEV adoption and usage patterns. PMID:22568681

  20. Implications of driving patterns on well-to-wheel performance of plug-in hybrid electric vehicles.

    PubMed

    Raykin, Leon; MacLean, Heather L; Roorda, Matthew J

    2012-06-01

    This study examines how driving patterns (distance and conditions) and the electricity generation supply interact to impact well-to-wheel (WTW) energy use and greenhouse gas (GHG) emissions of plug-in hybrid electric vehicles (PHEVs). The WTW performance of a PHEV is compared with that of a similar (nonplug-in) gasoline hybrid electric vehicle and internal combustion engine vehicle (ICEV). Driving PHEVs for short distances between recharging generally results in lower WTW total and fossil energy use and GHG emissions per kilometer compared to driving long distances, but the extent of the reductions depends on the electricity supply. For example, the shortest driving pattern in this study with hydroelectricity uses 81% less fossil energy than the longest driving pattern. However, the shortest driving pattern with coal-based electricity uses only 28% less fossil energy. Similar trends are observed in reductions relative to the nonplug-in vehicles. Irrespective of the electricity supply, PHEVs result in greater reductions in WTW energy use and GHG emissions relative to ICEVs for city than highway driving conditions. PHEVs charging from coal facilities only reduce WTW energy use and GHG emissions relative to ICEVs for certain favorable driving conditions. The study results have implications for environmentally beneficial PHEV adoption and usage patterns.

  1. Progress of the Computer-Aided Engineering of Electric Drive Vehicle Batteries (CAEBAT) (Presentation)

    SciTech Connect

    Pesaran, A. A.; Han, T.; Hartridge, S.; Shaffer, C.; Kim, G. H.; Pannala, S.

    2013-06-01

    This presentation, Progress of Computer-Aided Engineering of Electric Drive Vehicle Batteries (CAEBAT) is about simulation and computer-aided engineering (CAE) tools that are widely used to speed up the research and development cycle and reduce the number of build-and-break steps, particularly in the automotive industry. Realizing this, DOE?s Vehicle Technologies Program initiated the CAEBAT project in April 2010 to develop a suite of software tools for designing batteries.

  2. Climate Control Load Reduction Strategies for Electric Drive Vehicles in Warm Weather

    SciTech Connect

    Jeffers, M. A.; Chaney, L.; Rugh, J. P.

    2015-04-30

    Passenger compartment climate control is one of the largest auxiliary loads on a vehicle. Like conventional vehicles, electric vehicles (EVs) require climate control to maintain occupant comfort and safety, but cabin heating and air conditioning have a negative impact on driving range for all electric vehicles. Range reduction caused by climate control and other factors is a barrier to widespread adoption of EVs. Reducing the thermal loads on the climate control system will extend driving range, thereby reducing consumer range anxiety and increasing the market penetration of EVs. Researchers at the National Renewable Energy Laboratory have investigated strategies for vehicle climate control load reduction, with special attention toward EVs. Outdoor vehicle thermal testing was conducted on two 2012 Ford Focus Electric vehicles to evaluate thermal management strategies for warm weather, including solar load reduction and cabin pre-ventilation. An advanced thermal test manikin was used to assess a zonal approach to climate control. In addition, vehicle thermal analysis was used to support testing by exploring thermal load reduction strategies, evaluating occupant thermal comfort, and calculating EV range impacts. Through stationary cooling tests and vehicle simulations, a zonal cooling configuration demonstrated range improvement of 6%-15%, depending on the drive cycle. A combined cooling configuration that incorporated thermal load reduction and zonal cooling strategies showed up to 33% improvement in EV range.

  3. Batteries for electric drive vehicles: Evaluation of future characteristics and costs through a Delphi study

    SciTech Connect

    Vyas, A.D.; Ng, H.K.; Anderson, J.L.; Santini, D.J.

    1997-07-01

    Uncertainty about future costs and operating attributes of electric drive vehicles (EVs and HEVs) has contributed to considerable debate regarding the market viability of such vehicles. One way to deal with such uncertainty, common to most emerging technologies, is to pool the judgments of experts in the field. Data from a two-stage Delphi study are used to project the future costs and operating characteristics of electric drive vehicles. The experts projected basic vehicle characteristics for EVs and HEVs for the period 2000-2020. They projected the mean EV range at 179 km in 2000, 270 km in 2010, and 358 km in 2020. The mean HEV range on battery power was projected as 145 km in 2000, 212 km in 2010, and 244 km in 2020. Experts` opinions on 10 battery technologies are analyzed and characteristics of initial battery packs for the mean power requirements are presented. A procedure to compute the cost of replacement battery packs is described, and the resulting replacement costs are presented. Projected vehicle purchase prices and fuel and maintenance costs are also presented. The vehicle purchase price and curb weight predictions would be difficult to achieve with the mean battery characteristics. With the battery replacement costs added to the fuel and maintenance costs, the conventional ICE vehicle is projected to have a clear advantage over electric drive vehicles through the projection period.

  4. Nonsinusoidal electrical measurement accuracy in adjustable-speed motors and drives

    SciTech Connect

    Domijan, A.; Czarkowski, D.; Johnson, J.H.

    1998-11-01

    Accurate measurements of voltage, current, and power under nonsinusoidal conditions are essential for determining the efficiency of a drive system and performing separation of losses between an adjustable-speed drive (ASD) and an electric motor. That information is invaluable for equipment designers, manufacturers, and users. Three modern power meters and analyzers were tested to determine their accuracy with various nonsinusoidal waveforms applied. The meters were subjected to waveforms that are characteristic to the three most common fractional and integral horsepower ASD technologies, namely, pulsewidth modulation induction, brushless dc, and switched-reluctance drives. The tests were performed under field conditions and in a computer-controlled laboratory environment. The obtained results show that some meters are able to measure accurately electric power at the input to ASD`s. However, the output power of ASD`s for brushless dc and switched-reluctance technology was not measured with acceptable accuracy by any of the tested meters. Possible reasons of meters inaccuracies and suggestions for performance improvement are presented. Conclusions on the present state of ASD electric power measurements and recommendations for further research are given.

  5. Effect of electric field configuration on streamer and partial discharge phenomena in a hydrocarbon insulating liquid under AC stress

    NASA Astrophysics Data System (ADS)

    Liu, Z.; Liu, Q.; Wang, Z. D.

    2016-05-01

    This paper concerns pre-breakdown phenomena, including streamer characteristics from a fundamental perspective and partial discharge (PD) measurements from an industrial perspective, in a hydrocarbon insulating liquid. The aim was to investigate the possible changes of the liquid’s streamer and PD characteristics and their correlations when the uniformity of the AC electric field varies. In the experiments, a plane-to-plane electrode system incorporating a needle protrusion was used in addition to a needle-to-plane electrode system. When the applied electric field became more uniform, fewer radial branches occurred and streamer propagation towards the ground electrode was enhanced. The transition from streamer propagation dominated breakdown in divergent fields to streamer initiation dominated breakdown in uniform fields was evidenced. Relationships between streamer and PD characteristics were established, which were found to be electric field dependent. PD of the same apparent charge would indicate longer streamers if the electric field is more uniform.

  6. Kinesin-2 KIF3AC and KIF3AB Can Drive Long-Range Transport along Microtubules

    PubMed Central

    Guzik-Lendrum, Stephanie; Rank, Katherine C.; Bensel, Brandon M.; Taylor, Keenan C.; Rayment, Ivan; Gilbert, Susan P.

    2015-01-01

    Mammalian KIF3AC is classified as a heterotrimeric kinesin-2 that is best known for organelle transport in neurons, yet in vitro studies to characterize its single molecule behavior are lacking. The results presented show that a KIF3AC motor that includes the native helix α7 sequence for coiled-coil formation is highly processive with run lengths of ∼1.23 μm and matching those exhibited by conventional kinesin-1. This result was unexpected because KIF3AC exhibits the canonical kinesin-2 neck-linker sequence that has been reported to be responsible for shorter run lengths observed for another heterotrimeric kinesin-2, KIF3AB. However, KIF3AB with its native neck linker and helix α7 is also highly processive with run lengths of ∼1.62 μm and exceeding those of KIF3AC and kinesin-1. Loop L11, a component of the microtubule-motor interface and implicated in activating ADP release upon microtubule collision, is significantly extended in KIF3C as compared with other kinesins. A KIF3AC encoding a truncation in KIF3C loop L11 (KIF3ACΔL11) exhibited longer run lengths at ∼1.55 μm than wild-type KIF3AC and were more similar to KIF3AB run lengths, suggesting that L11 also contributes to tuning motor processivity. The steady-state ATPase results show that shortening L11 does not alter kcat, consistent with the observation that single molecule velocities are not affected by this truncation. However, shortening loop L11 of KIF3C significantly increases the microtubule affinity of KIF3ACΔL11, revealing another structural and mechanistic property that can modulate processivity. The results presented provide new, to our knowledge, insights to understand structure-function relationships governing processivity and a better understanding of the potential of KIF3AC for long-distance transport in neurons. PMID:26445448

  7. Oak Ridge National Laboratory Annual Progress Report for the Electric Drive Technologies Program

    SciTech Connect

    Ozpineci, Burak

    2015-10-01

    The US Department of Energy (DOE) announced in May 2011 a new cooperative research effort comprising DOE, the US Council for Automotive Research (composed of automakers Ford Motor Company, General Motors Company, and Chrysler Group), Tesla Motors, and representatives of the electric utility and petroleum industries. Known as U.S. DRIVE (Driving Research and Innovation for Vehicle efficiency and Energy sustainability), it represents DOE’s commitment to developing public–private partnerships to fund high-risk–high-reward research into advanced automotive technologies. The new partnership replaces and builds upon the partnership known as FreedomCAR (derived from “Freedom” and “Cooperative Automotive Research”) that ran from 2002 through 2010 and the Partnership for a New Generation of Vehicles initiative that ran from 1993 through 2001. Oak Ridge National Laboratory’s (ORNL’s) Electric Drive Technologies (EDT) subprogram within the DOE Vehicle Technologies Office (VTO) provides support and guidance for many cutting-edge automotive technologies now under development. Research is focused on developing revolutionary new power electronics (PE), electric motor (EM), and traction drive system (TDS) technologies that will leapfrog current on-the-road technologies, leading to lower cost and better efficiency in transforming battery energy to useful work. The research and development (R&D) is also aimed at achieving a greater understanding of and improvements in the way the various new components of tomorrow’s automobiles will function as a unified system to improve fuel efficiency through research in more efficient TDSs. In supporting the development of advanced vehicle propulsion systems, the EDT subprogram fosters the development of technologies that will significantly improve efficiency, costs, and fuel economy

  8. The Measurement of Surface Cracks in Metals by Using a.c. Electric Fields

    NASA Astrophysics Data System (ADS)

    Michael, D. H.; Waechter, R. T.; Collins, R.

    1982-05-01

    This paper describes some recent studies associated with the development of an instrument, the Crack Microgauge, at University College London, for the detection and measurement of surface cracks in metals by using a.c. electric currents in the metal surface. The design of the instrument has enhanced the accuracy of measurement of surface voltages in the neighbourhood of surface-breaking cracks to the point where it is now advantageous to consider the distribution of surface voltages by mathematical analysis. This enables better use to be made of the instrument since measurements can then be more accurately interpreted in terms of crack size and geometry. In contrast, earlier applications of the method relied on the calibration of the instruments against test blocks. The first generation of users of the Crack Microgauge interpreted their readings according to a simple one-dimensional normal crack model. This, however, is an oversimplification for cracks of finite aspect ratio and it leads to underestimates of centre-line crack depth typically of the order of 30-40<%> when the aspect ratio is about 3. The first major contribution of the theory was therefore to provide a model for surface current flow around cracks of finite aspect ratio. For this purpose a useful unfolding theorem was deduced in cases in which the current skin depth is small compared with crack dimensions. This allows the surface field to be unfolded into a plane distribution of potential satisfying Laplace's equation, and it enables us to obtain solutions for many different crack shapes by using standard mathematical methods. An account of these developments is given in ξ 2 of this paper. The unfolding of the surface field gives the global distribution of surface current around a crack, that is, on the length scale of the crack dimensions. On the length scale of the skin depth, however, the solutions need modification in the neighbourhood of the surface and interior edges of the crack. In

  9. Causal Analysis of the Inadvertent Contact with an Uncontrolled Electrical Hazardous Energy Source (120 Volts AC)

    SciTech Connect

    David E. James; Dennis E. Raunig; Sean S. Cunningham

    2014-10-01

    On September 25, 2013, a Health Physics Technician (HPT) was performing preparations to support a pneumatic transfer from the HFEF Decon Cell to the Room 130 Glovebox in HFEF, per HFEF OI 3165 section 3.5, Field Preparations. This activity involves an HPT setting up and climbing a portable ladder to remove the 14-C meter probe from above ball valve HBV-7. The HPT source checks the meter and probe and then replaces the probe above HBV-7, which is located above Hood ID# 130 HP. At approximately 13:20, while reaching past the HBV-7 valve position indicator switches in an attempt to place the 14-C meter probe in the desired location, the HPT’s left forearm came in contact with one of the three sets of exposed terminals on the valve position indication switches for HBV 7. This resulted in the HPT receiving an electrical shock from a 120 Volt AC source. Upon moving the arm, following the electrical shock, the HPT noticed two exposed electrical connections on a switch. The HPT then notified the HFEF HPT Supervisor, who in turn notified the MFC Radiological Controls Manager and HFEF Operations Manager of the situation. Work was stopped in the area and the hazard was roped off and posted to prevent access to the hazard. The HPT was escorted by the HPT Supervisor to the MFC Dispensary and then preceded to CFA medical for further evaluation. The individual was evaluated and released without any medical restrictions. Causal Factor (Root Cause) A3B3C01/A5B2C08: - Knowledge based error/Attention was given to wrong issues - Written Communication content LTA, Incomplete/situation not covered The Causal Factor (root cause) was attention being given to the wrong issues during the creation, reviews, verifications, and actual performance of HFEF OI-3165, which covers the need to perform the weekly source check and ensure placement of the probe prior to performing a “rabbit” transfer. This resulted in the hazard not being identified and mitigated in the procedure. Work activities

  10. Evaluation of 2004 Toyota Prius Hybrid Electric Drive System Interim Report

    SciTech Connect

    Ayers, C.W.

    2004-11-23

    Laboratory tests were conducted to evaluate the electrical and mechanical performance of the 2004 Toyota Prius and its hybrid electric drive system. As a hybrid vehicle, the 2004 Prius uses both a gasoline-powered internal combustion engine and a battery-powered electric motor as motive power sources. Innovative algorithms for combining these two power sources results in improved fuel efficiency and reduced emissions compared to traditional automobiles. Initial objectives of the laboratory tests were to measure motor and generator back-electromotive force (emf) voltages and determine gearbox-related power losses over a specified range of shaft speeds and lubricating oil temperatures. Follow-on work will involve additional performance testing of the motor, generator, and inverter. Information contained in this interim report summarizes the test results obtained to date, describes preliminary conclusions and findings, and identifies additional areas for further study.

  11. Speed Sensorless Induction Motor Drives for Electrical Actuators: Schemes, Trends and Tradeoffs

    NASA Technical Reports Server (NTRS)

    Elbuluk, Malik E.; Kankam, M. David

    1997-01-01

    For a decade, induction motor drive-based electrical actuators have been under investigation as potential replacement for the conventional hydraulic and pneumatic actuators in aircraft. Advantages of electric actuator include lower weight and size, reduced maintenance and operating costs, improved safety due to the elimination of hazardous fluids and high pressure hydraulic and pneumatic actuators, and increased efficiency. Recently, the emphasis of research on induction motor drives has been on sensorless vector control which eliminates flux and speed sensors mounted on the motor. Also, the development of effective speed and flux estimators has allowed good rotor flux-oriented (RFO) performance at all speeds except those close to zero. Sensorless control has improved the motor performance, compared to the Volts/Hertz (or constant flux) controls. This report evaluates documented schemes for speed sensorless drives, and discusses the trends and tradeoffs involved in selecting a particular scheme. These schemes combine the attributes of the direct and indirect field-oriented control (FOC) or use model adaptive reference systems (MRAS) with a speed-dependent current model for flux estimation which tracks the voltage model-based flux estimator. Many factors are important in comparing the effectiveness of a speed sensorless scheme. Among them are the wide speed range capability, motor parameter insensitivity and noise reduction. Although a number of schemes have been proposed for solving the speed estimation, zero-speed FOC with robustness against parameter variations still remains an area of research for speed sensorless control.

  12. Sensitivity of Battery Electric Vehicle Economics to Drive Patterns, Vehicle Range, and Charge Strategies

    SciTech Connect

    Neubauer, J.; Brooker, A.; Wood, E.

    2012-07-01

    Battery electric vehicles (BEVs) offer the potential to reduce both oil imports and greenhouse gas emissions, but high upfront costs discourage many potential purchasers. Making an economic comparison with conventional alternatives is complicated in part by strong sensitivity to drive patterns, vehicle range, and charge strategies that affect vehicle utilization and battery wear. Identifying justifiable battery replacement schedules and sufficiently accounting for the limited range of a BEV add further complexity to the issue. The National Renewable Energy Laboratory developed the Battery Ownership Model to address these and related questions. The Battery Ownership Model is applied here to examine the sensitivity of BEV economics to drive patterns, vehicle range, and charge strategies when a high-fidelity battery degradation model, financially justified battery replacement schedules, and two different means of accounting for a BEV's unachievable vehicle miles traveled (VMT) are employed. We find that the value of unachievable VMT with a BEV has a strong impact on the cost-optimal range, charge strategy, and battery replacement schedule; that the overall cost competitiveness of a BEV is highly sensitive to vehicle-specific drive patterns; and that common cross-sectional drive patterns do not provide consistent representation of the relative cost of a BEV.

  13. Battery Electric Vehicle Driving and Charging Behavior Observed Early in The EV Project

    SciTech Connect

    John Smart; Stephen Schey

    2012-04-01

    As concern about society's dependence on petroleum-based transportation fuels increases, many see plug-in electric vehicles (PEV) as enablers to diversifying transportation energy sources. These vehicles, which include plug-in hybrid electric vehicles (PHEV), range-extended electric vehicles (EREV), and battery electric vehicles (BEV), draw some or all of their power from electricity stored in batteries, which are charged by the electric grid. In order for PEVs to be accepted by the mass market, electric charging infrastructure must also be deployed. Charging infrastructure must be safe, convenient, and financially sustainable. Additionally, electric utilities must be able to manage PEV charging demand on the electric grid. In the Fall of 2009, a large scale PEV infrastructure demonstration was launched to deploy an unprecedented number of PEVs and charging infrastructure. This demonstration, called The EV Project, is led by Electric Transportation Engineering Corporation (eTec) and funded by the U.S. Department of Energy. eTec is partnering with Nissan North America to deploy up to 4,700 Nissan Leaf BEVs and 11,210 charging units in five market areas in Arizona, California, Oregon, Tennessee, and Washington. With the assistance of the Idaho National Laboratory, eTec will collect and analyze data to characterize vehicle consumer driving and charging behavior, evaluate the effectiveness of charging infrastructure, and understand the impact of PEV charging on the electric grid. Trials of various revenue systems for commercial and public charging infrastructure will also be conducted. The ultimate goal of The EV Project is to capture lessons learned to enable the mass deployment of PEVs. This paper is the first in a series of papers documenting the progress and findings of The EV Project. This paper describes key research objectives of The EV Project and establishes the project background, including lessons learned from previous infrastructure deployment and PEV

  14. An optimal torque distribution control strategy for four-independent wheel drive electric vehicles

    NASA Astrophysics Data System (ADS)

    Li, Bin; Goodarzi, Avesta; Khajepour, Amir; Chen, Shih-ken; Litkouhi, Baktiar

    2015-08-01

    In this paper, an optimal torque distribution approach is proposed for electric vehicle equipped with four independent wheel motors to improve vehicle handling and stability performance. A novel objective function is formulated which works in a multifunctional way by considering the interference among different performance indices: forces and moment errors at the centre of gravity of the vehicle, actuator control efforts and tyre workload usage. To adapt different driving conditions, a weighting factors tuning scheme is designed to adjust the relative weight of each performance in the objective function. The effectiveness of the proposed optimal torque distribution is evaluated by simulations with CarSim and Matlab/Simulink. The simulation results under different driving scenarios indicate that the proposed control strategy can effectively improve the vehicle handling and stability even in slippery road conditions.

  15. Optimal investment and scheduling of distributed energy resources with uncertainty in electric vehicles driving schedules

    SciTech Connect

    Cardoso, Goncalo; Stadler, Michael; Bozchalui, Mohammed C.; Sharma, Ratnesh; Marnay, Chris; Barbosa-Povoa, Ana; Ferrao, Paulo

    2013-12-06

    The large scale penetration of electric vehicles (EVs) will introduce technical challenges to the distribution grid, but also carries the potential for vehicle-to-grid services. Namely, if available in large enough numbers, EVs can be used as a distributed energy resource (DER) and their presence can influence optimal DER investment and scheduling decisions in microgrids. In this work, a novel EV fleet aggregator model is introduced in a stochastic formulation of DER-CAM [1], an optimization tool used to address DER investment and scheduling problems. This is used to assess the impact of EV interconnections on optimal DER solutions considering uncertainty in EV driving schedules. Optimization results indicate that EVs can have a significant impact on DER investments, particularly if considering short payback periods. Furthermore, results suggest that uncertainty in driving schedules carries little significance to total energy costs, which is corroborated by results obtained using the stochastic formulation of the problem.

  16. The PEGASUS Drive: A nuclear electric propulsion system for the space exploration initiative

    SciTech Connect

    Coomes, E.P.; Dagle, J.E.

    1990-10-01

    The advantages of using electric propulsion for propulsion are well-known in the aerospace community. The high specific impulse, lower propellant requirements, and lower system mass make it a very attractive propulsion option for the Space Exploration Initiative (SEI), especially for the transport of cargo. One such propulsion system is the PEGASUS Drive (Coomes et al. 1987). In its original configuration, the PEGASUS Drive consisted of a 10-MWe power source coupled to a 6-MW magnetoplasmadynamic (MPD) thruster system. The PEGASUS Drive propelled a manned vehicle to Mars and back in 601 days. By removing the crew and their associated support systems from the spacecraft and by incorporating technology advances in reactor design and heat rejection systems, a second generation PEGASUS Drive can be developed with an alpha less than two. Utilizing this propulsion system, a 400-MT cargo vehicle, assembled and loaded in low Earth orbit (LEO), could deliver 262 MT of supplies and hardware to Mars 282 days after escaping Earth orbit. Upon arrival at Mars the transport vehicle would place its cargo in the desired parking orbit around Mars and then proceed to synchronous orbit above the desired landing sight. Using a laser transmitter, PEGASUS would provide 2-MWe on the surface to operate automated systems deployed earlier and then provide surface power to support crew activities after their arrival. The additional supplies and hardware, coupled with the availability of megawatt levels of electric power on the Mars surface, would greatly enhance and even expand the mission options being considered under SEI. 9 refs., 1 fig., 1 tab.

  17. Study on AC-DC Electrical Conductivities in Warm Dense Matter Generated by Pulsed-power Discharge with Isochoric Vessel

    NASA Astrophysics Data System (ADS)

    Sasaki, Toru; Ohuchi, Takumi; Takahashi, Takuya; Kawaguchi, Yoshinari; Saito, Hirotaka; Miki, Yasutoshi; Takahashi, Kazumasa; Kikuchi, Takashi; Aso, Tsukasa; Harada, Nob.

    2016-03-01

    To observe AC and DC electrical conductivity in warm dense matter (WDM), we have demonstrated to apply the spectroscopic ellipsometry for a pulsed-power discharge with isochoric vessel. At 10 μs from the beginning of discharge, the generated parameters by using pulsed-power discharge with isochoric vessel are 0.1 ρ s (ρ s: solid density) of density and 4000 K of temperature, respectively. The DC electrical conductivity for above parameters is estimated to be 104 S/m. In order to measure the AC electrical conductivity, we have developed a four-detector spectroscopic ellipsometer with a multichannel spectrometer. The multichannel spectrometer, in which consists of a 16-channel photodiode array, a two-stages voltage adder, and a flat diffraction grating, has 10 MHz of the frequency response with covered visible spectrum. For applying the four-detector spectroscopic ellipsometer, we observe the each observation signal evolves the polarized behavior compared to the ratio as I 1/I 2.

  18. Modeling, Simulation Design and Control of Hybrid-Electric Vehicle Drives

    SciTech Connect

    Giorgio Rizzoni

    2005-09-30

    Ohio State University (OSU) is uniquely poised to establish such a center, with interdisciplinary emphasis on modeling, simulation, design and control of hybrid-electric drives for a number of reasons, some of which are: (1) The OSU Center for Automotive Research (CAR) already provides an infrastructure for interdisciplinary automotive research and graduate education; the facilities available at OSU-CAR in the area of vehicle and powertrain research are among the best in the country. CAR facilities include 31,000 sq. feet of space, multiple chassis and engine dynamometers, an anechoic chamber, and a high bay area. (2) OSU has in excess of 10 graduate level courses related to automotive systems. A graduate level sequence has already been initiated with GM. In addition, an Automotive Systems Engineering (ASE) program cosponsored by the mechanical and electrical engineering programs, had been formulated earlier at OSU, independent of the GATE program proposal. The main objective of the ASE is to provide multidisciplinary graduate education and training in the field of automotive systems to Masters level students. This graduate program can be easily adapted to fulfill the spirit of the GATE Center of Excellence. (3) A program in Mechatronic Systems Engineering has been in place at OSU since 1994; this program has a strong emphasis on automotive system integration issues, and has emphasized hybrid-electric vehicles as one of its application areas. (4) OSU researchers affiliated with CAR have been directly involved in the development and study of: HEV modeling and simulation; electric drives; transmission design and control; combustion engines; and energy storage systems. These activities have been conducted in collaboration with government and automotive industry sponsors; further, the same researchers have been actively involved in continuing education programs in these areas with the automotive industry. The proposed effort will include: (1) The development of a

  19. A modified integral sliding mode control to lateral stabilisation of 4-wheel independent drive electric vehicles

    NASA Astrophysics Data System (ADS)

    Alipour, Hasan; Bagher Bannae Sharifian, Mohammad; Sabahi, Mehran

    2014-12-01

    This paper presents a novel sliding mode controller (SMC) and its application in the lateral stability control of a 4-wheel independent drive electric vehicle. The structure of the SMC is modified and online-tuned to ensure vehicle system stability, and to track the desired vehicle motion references when an in-wheel motor fault happens. The proposed controller is faster, more accurate, more robust, and with smaller chattering than common SMCs chatter. The effectiveness of the introduced approach is investigated through conducted simulations in the CARSIM and MATLAB software environments.

  20. Model predictive torque control with an extended prediction horizon for electrical drive systems

    NASA Astrophysics Data System (ADS)

    Wang, Fengxiang; Zhang, Zhenbin; Kennel, Ralph; Rodríguez, José

    2015-07-01

    This paper presents a model predictive torque control method for electrical drive systems. A two-step prediction horizon is achieved by considering the reduction of the torque ripples. The electromagnetic torque and the stator flux error between predicted values and the references, and an over-current protection are considered in the cost function design. The best voltage vector is selected by minimising the value of the cost function, which aims to achieve a low torque ripple in two intervals. The study is carried out experimentally. The results show that the proposed method achieves good performance in both steady and transient states.

  1. AC Electric Field-Induced Trapping of Microparticles in Pinched Microconfinements.

    PubMed

    Dey, Ranabir; Shaik, Vaseem Akram; Chakraborty, Debapriya; Ghosal, Sandip; Chakraborty, Suman

    2015-06-01

    The trapping of charged microparticles under confinement in a converging-diverging microchannel, under a symmetric AC field of tunable frequency, is studied. We show that at low frequencies, the trapping characteristics stem from the competing effects of positive dielectrophoresis and the linear electrokinetic phenomena of electroosmosis and electrophoresis. It is found, somewhat unexpectedly, that electroosmosis and electrophoresis significantly affect the concentration profile of the trapped analyte, even for a symmetric AC field. However, at intermediate frequencies, the microparticle trapping mechanism is predominantly a consequence of positive dielectrophoresis. We substantiate our experimental results for the microparticle concentration distribution, along the converging-diverging microchannel, with a detailed theoretical analysis that takes into account all of the relevant frequency-dependent electrokinetic phenomena. This study should be useful in understanding the response of biological components such as cells to applied AC fields. Moreover, it will have potential applications in the design of efficient point-of-care diagnostic devices for detecting biomarkers and also possibly in some recent strategies in cancer therapy using AC fields. PMID:25954982

  2. Module Twelve: Series AC Resistive-Reactive Circuits; Basic Electricity and Electronics Individualized Learning System.

    ERIC Educational Resources Information Center

    Bureau of Naval Personnel, Washington, DC.

    The module covers series circuits which contain both resistive and reactive components and methods of solving these circuits for current, voltage, impedance, and phase angle. The module is divided into six lessons: voltage and impedance in AC (alternating current) series circuits, vector computations, rectangular and polar notation, variational…

  3. High-voltage Array Ground Test for Direct-drive Solar Electric Propulsion

    NASA Technical Reports Server (NTRS)

    Howell, Joe T.; Mankins, John C.; O'Neill, Mark J.

    2005-01-01

    Development is underway on a unique high-power solar concentrator array called Stretched Lens Array (SLA) for direct drive electric propulsion. These SLA performance attributes closely match the critical needs of solar electric propulsion (SEP) systems, which may be used for "space tugs" to fuel-efficiently transport cargo from low earth orbit (LEO) to low lunar orbit (LLO), in support of NASA s robotic and human exploration missions. Later SEP systems may similarly transport cargo from the earth-moon neighborhood to the Mars neighborhood. This paper will describe the SLA SEP technology, discuss ground tests already completed, and present plans for future ground tests and future flight tests of SLA SEP systems.

  4. Control algorithm of electric vehicle in coasting mode based on driving feeling

    NASA Astrophysics Data System (ADS)

    Sun, Daxu; Lan, Fengchong; Zhou, Yunjiao; Chen, Jiqing

    2015-05-01

    Coasting in gear is a common driving mode for the conventional vehicle equipped with the internal combustion engine (ICE), and the assistant braking function of ICE is utilized to decelerate the vehicle in this mode. However, the electric vehicle (EV) does not have this feature in the coasting mode due to the relatively small inertia of the driving motor, so it will cause the driver cannot obtain the similar driving feeling to that of the conventional vehicle, and even a traffic accident may occur if the driver cannot immediately adapt to the changes. In this paper, the coasting control for EV is researched based on the driving feeling. A conventional vehicle equipped with continuously variable transmission (CVT) is taken as the reference vehicle, and the combined simulation model of EV is established based on AVL CRUISE and MATLAB/Simulink. The torque characteristic of the CVT output shaft is measured in coasting mode, and the data are smoothed and fitted to a polynomial curve. For the EV in coasting mode, if the state of charge (SOC) of the battery is below 95%, the polynomial curve is used as the control target for the torque characteristic of the driving motor, otherwise, the required torque is replaced by hydraulic braking torque to keep the same deceleration. The co-simulation of Matlab/Simulink/Stateflow and AVL CRUISE, as well as the hardware-in-loop experiment combined with dSPACE are carried out to verify the effectiveness and the real-time performance of the control algorithm. The results show that the EV with coasting braking control system has similar driving feeling to that of the reference vehicle, meanwhile, the battery SOC can be increased by 0.036% and 0.021% in the initial speed of 100 km/h and 50 km/h, respectively. The proposed control algorithm for EV is beneficial to improve the driving feeling in coasting mode, and it also makes the EV has the assistant braking function.

  5. Statistical Characterization of Medium-Duty Electric Vehicle Drive Cycles: Preprint

    SciTech Connect

    Prohaska, R.; Duran, A.; Ragatz, A.; Kelly, K.

    2015-05-01

    In an effort to help commercialize technologies for electric vehicles (EVs) through deployment and demonstration projects, the U.S. Department of Energy’s (DOE's) American Recovery and Reinvestment Act (ARRA) provided funding to participating U.S. companies to cover part of the cost of purchasing new EVs. Within the medium- and heavy-duty commercial vehicle segment, both Smith Electric Newton and and Navistar eStar vehicles qualified for such funding opportunities. In an effort to evaluate the performance characteristics of the new technologies deployed in these vehicles operating under real world conditions, data from Smith Electric and Navistar medium-duty EVs were collected, compiled, and analyzed by the National Renewable Energy Laboratory's (NREL) Fleet Test and Evaluation team over a period of 3 years. More than 430 Smith Newton EVs have provided data representing more than 150,000 days of operation. Similarly, data have been collected from more than 100 Navistar eStar EVs, resulting in a comparative total of more than 16,000 operating days. Combined, NREL has analyzed more than 6 million kilometers of driving and 4 million hours of charging data collected from commercially operating medium-duty electric vehicles in various configurations. In this paper, extensive duty-cycle statistical analyses are performed to examine and characterize common vehicle dynamics trends and relationships based on in-use field data. The results of these analyses statistically define the vehicle dynamic and kinematic requirements for each vehicle, aiding in the selection of representative chassis dynamometer test cycles and the development of custom drive cycles that emulate daily operation. In this paper, the methodology and accompanying results of the duty-cycle statistical analysis are presented and discussed. Results are presented in both graphical and tabular formats illustrating a number of key relationships between parameters observed within the data set that relate to

  6. Drive Control Scheme of Electric Power Assisted Wheelchair Based on Neural Network Learning of Human Wheelchair Operation Characteristics

    NASA Astrophysics Data System (ADS)

    Tanohata, Naoki; Seki, Hirokazu

    This paper describes a novel drive control scheme of electric power assisted wheelchairs based on neural network learning of human wheelchair operation characteristics. “Electric power assisted wheelchair” which enhances the drive force of the operator by employing electric motors is expected to be widely used as a mobility support system for elderly and disabled people. However, some handicapped people with paralysis of the muscles of one side of the body cannot maneuver the wheelchair as desired because of the difference in the right and left input force. Therefore, this study proposes a neural network learning system of such human wheelchair operation characteristics and a drive control scheme with variable distribution and assistance ratios. Some driving experiments will be performed to confirm the effectiveness of the proposed control system.

  7. Electrically driving large magnetic Reynolds number flows on the Madison plasma dynamo experiment

    NASA Astrophysics Data System (ADS)

    Weisberg, David; Wallace, John; Peterson, Ethan; Endrezzi, Douglass; Forest, Cary B.; Desangles, Victor

    2015-11-01

    Electrically-driven plasma flows, predicted to excite a large-scale dynamo instability, have been generated in the Madison plasma dynamo experiment (MPDX), at the Wisconsin Plasma Astrophysics Laboratory. Numerical simulations show that certain topologies of these simply-connected flows may be optimal for creating a plasma dynamo and predict critical thresholds as low as Rmcrit =μ0 σLV = 250 . MPDX plasmas are shown to exceed this critical Rm , generating large (L = 1 . 4 m), warm (Te > 10 eV), unmagnetized (MA > 1) plasmas where Rm < 600 . Plasma flow is driven using ten thermally emissive LaB6 cathodes which generate a J × B torque in Helium plasmas. Detailed Mach probe measurements of plasma velocity for two flow topologies will be presented: edge-localized drive using the multi-cusp boundary field, and volumetric drive using an axial Helmholtz field. Radial velocity profiles show that edge-driven flow is established via ion viscosity but is limited by a volumetric neutral drag force (χ ~ 1 / (ντin)), and measurements of velocity shear compare favorably to Braginskii transport theory. Volumetric flow drive is shown to produce stronger velocity shear, and is characterized by the radial potential gradient as determined by global charge balance.

  8. Electric characterization of (Sr, Sr-Ba, Ba) M-type ferrites by AC measurements[Alternating Current

    SciTech Connect

    Huanosta-Tera, A.; Lira-Hueso, R. de; Perez-Orta, O.; Palomares-Sanchez, S.A.; Ponce-Castaneda, S.; Mirabal-Garcia, M.

    2000-02-01

    Considering the electrical conductivity in ceramics, necessary reference should be given to dynamic processes occurring as a function of frequency and temperature. Although the most immediate interest in ferrites lies in their magnetic properties, technological applications require a wider knowledge of general physical properties as well. This is especially applicable when the materials are studied as a function of composition or when adding different modifiers. In this report, the authors present results of the ac and dc electric characteristics of a family of magneto-plumbite-type hexaferrites, where Ba gradually substitutes Sr in the Ba{sub x}Sr{sub 1{minus}x}Fe{sub 12}O{sub 19} compound (0 {le} x {le} 1). The results were determined over a wide range of frequencies and temperatures.

  9. Characterization of In-Use Medium Duty Electric Vehicle Driving and Charging Behavior: Preprint

    SciTech Connect

    Duran, A.; Ragatz, A.; Prohaska, R.; Kelly, K.; Walkowicz, K.

    2014-11-01

    The U.S. Department of Energy's American Recovery and Reinvestment Act (ARRA) deployment and demonstration projects are helping to commercialize technologies for all-electric vehicles (EVs). Under the ARRA program, data from Smith Electric and Navistar medium duty EVs have been collected, compiled, and analyzed in an effort to quantify the impacts of these new technologies. Over a period of three years, the National Renewable Energy Laboratory (NREL) has compiled data from over 250 Smith Newton EVs for a total of over 100,000 days of in-use operation. Similarly, data have been collected from over 100 Navistar eStar vehicles, with over 15,000 operating days having been analyzed. NREL has analyzed a combined total of over 4 million kilometers of driving and 1 million hours of charging data for commercial operating medium duty EVs. In this paper, the authors present an overview of medium duty EV operating and charging behavior based on in-use data collected from both Smith and Navistar vehicles operating in the United States. Specifically, this paper provides an introduction to the specifications and configurations of the vehicles examined; discusses the approach and methodology of data collection and analysis, and presents detailed results regarding daily driving and charging behavior. In addition, trends observed over the course of multiple years of data collection are examined, and conclusions are drawn about early deployment behavior and ongoing adjustments due to new and improving technology. Results and metrics such as average daily driving distance, route aggressiveness, charging frequency, and liter per kilometer diesel equivalent fuel consumption are documented and discussed.

  10. Direct yaw moment control for distributed drive electric vehicle handling performance improvement

    NASA Astrophysics Data System (ADS)

    Yu, Zhuoping; Leng, Bo; Xiong, Lu; Feng, Yuan; Shi, Fenmiao

    2016-05-01

    For a distributed drive electric vehicle (DDEV) driven by four in-wheel motors, advanced vehicle dynamic control methods can be realized easily because motors can be controlled independently, quickly and precisely. And direct yaw-moment control (DYC) has been widely studied and applied to vehicle stability control. Good vehicle handling performance: quick yaw rate transient response, small overshoot, high steady yaw rate gain, etc, is required by drivers under normal conditions, which is less concerned, however. Based on the hierarchical control methodology, a novel control system using direct yaw moment control for improving handling performance of a distributed drive electric vehicle especially under normal driving conditions has been proposed. The upper-loop control system consists of two parts: a state feedback controller, which aims to realize the ideal transient response of yaw rate, with a vehicle sideslip angle observer; and a steering wheel angle feedforward controller designed to achieve a desired yaw rate steady gain. Under the restriction of the effect of poles and zeros in the closed-loop transfer function on the system response and the capacity of in-wheel motors, the integrated time and absolute error (ITAE) function is utilized as the cost function in the optimal control to calculate the ideal eigen frequency and damper coefficient of the system and obtain optimal feedback matrix and feedforward matrix. Simulations and experiments with a DDEV under multiple maneuvers are carried out and show the effectiveness of the proposed method: yaw rate rising time is reduced, steady yaw rate gain is increased, vehicle steering characteristic is close to neutral steer and drivers burdens are also reduced. The control system improves vehicle handling performance under normal conditions in both transient and steady response. State feedback control instead of model following control is introduced in the control system so that the sense of control intervention to

  11. Effect of nanosilica on optical, electric modulus and AC conductivity of polyvinyl alcohol/polyaniline films

    NASA Astrophysics Data System (ADS)

    El-Sayed, Somyia; Abel-Baset, Tarob; Elfadl, Azza Abou; Hassen, Arafa

    2015-05-01

    Nanosilica (NS) was synthesized by a sol-gel method and mixed with 0.98 polyvinyl alcohol (PVA)/0.02 polyaniline (PANI) in different amounts to produce nanocomposite films. High-resolution transmission electron microscopy (HR-TEM) revealed the average particle size of the NS to be ca. 15 nm. Scanning electron microscopy (SEM) showed that the NS was well-dispersed on the surface of the PVA/PNAI films. The Fourier transform infrared (FTIR) spectra of the samples showed a significant change in the intensity of the characteristic peak of the functional groups in the composite films with the amount of NS added. The absorbance and refractive index (n) of the composites were studied in the UV-vis range, and the optical energy band gap, Eg, and different optical parameters were calculated. The dielectric loss modulus, M″ and ac conductivity, σac, of the samples were studied within 300-425 K and 0.1 kHz-5 MHz, respectively. Two relaxation peaks were observed in the frequency dependence of the dielectric loss modulus, M″. The behavior of σac(f) for the composite films indicated that the conduction mechanism was correlated barrier hopping (CBH). The results of this work are discussed and compared with those of previous studies of similar composites.

  12. How much do electric drive vehicles matter to future U.S. emissions?

    PubMed

    Babaee, Samaneh; Nagpure, Ajay S; DeCarolis, Joseph F

    2014-01-01

    Hybrid, plug-in hybrid, and battery electric vehicles--known collectively as electric drive vehicles (EDVs)--may represent a clean and affordable option to meet growing U.S. light duty vehicle (LDV) demand. The goal of this study is 2-fold: identify the conditions under which EDVs achieve high LDV market penetration in the U.S. and quantify the associated change in CO2, SO2, and NOX emissions through midcentury. We employ the Integrated MARKAL-EFOM System (TIMES), a bottom-up energy system model, along with a U.S. data set developed for this analysis. To characterize EDV deployment through 2050, varying assumptions related to crude oil and natural gas prices, a CO2 policy, a federal renewable portfolio standard, and vehicle battery cost were combined to form 108 different scenarios. Across these scenarios, oil prices and battery cost have the biggest effect on EDV deployment. The model results do not demonstrate a clear and consistent trend toward lower system-wide emissions as EDV deployment increases. In addition to the trade-off between lower tailpipe and higher electric sector emissions associated with plug-in vehicles, the scenarios produce system-wide emissions effects that often mask the effect of EDV deployment. PMID:24386958

  13. How much do electric drive vehicles matter to future U.S. emissions?

    PubMed

    Babaee, Samaneh; Nagpure, Ajay S; DeCarolis, Joseph F

    2014-01-01

    Hybrid, plug-in hybrid, and battery electric vehicles--known collectively as electric drive vehicles (EDVs)--may represent a clean and affordable option to meet growing U.S. light duty vehicle (LDV) demand. The goal of this study is 2-fold: identify the conditions under which EDVs achieve high LDV market penetration in the U.S. and quantify the associated change in CO2, SO2, and NOX emissions through midcentury. We employ the Integrated MARKAL-EFOM System (TIMES), a bottom-up energy system model, along with a U.S. data set developed for this analysis. To characterize EDV deployment through 2050, varying assumptions related to crude oil and natural gas prices, a CO2 policy, a federal renewable portfolio standard, and vehicle battery cost were combined to form 108 different scenarios. Across these scenarios, oil prices and battery cost have the biggest effect on EDV deployment. The model results do not demonstrate a clear and consistent trend toward lower system-wide emissions as EDV deployment increases. In addition to the trade-off between lower tailpipe and higher electric sector emissions associated with plug-in vehicles, the scenarios produce system-wide emissions effects that often mask the effect of EDV deployment.

  14. Frequency and voltage dependence dielectric properties, ac electrical conductivity and electric modulus profiles in Al/Co3O4-PVA/p-Si structures

    NASA Astrophysics Data System (ADS)

    Bilkan, Çiğdem; Azizian-Kalandaragh, Yashar; Altındal, Şemsettin; Shokrani-Havigh, Roya

    2016-11-01

    In this research a simple microwave-assisted method have been used for preparation of cobalt oxide nanostructures. The as-prepared sample has been investigated by UV-vis spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM). On the other hand, frequency and voltage dependence of both the real and imaginary parts of dielectric constants (ε‧, ε″) and electric modulus (M‧ and M″), loss tangent (tanδ), and ac electrical conductivity (σac) values of Al/Co3O4-PVA/p-Si structures were obtained in the wide range of frequency and voltage using capacitance (C) and conductance (G/ω) data at room temperature. The values of ε‧, ε″ and tanδ were found to decrease with increasing frequency almost for each applied bias voltage, but the changes in these parameters become more effective in the depletion region at low frequencies due to the charges at surface states and their relaxation time and polarization effect. While the value of σ is almost constant at low frequency, increases almost as exponentially at high frequency which are corresponding to σdc and σac, respectively. The M‧ and M″ have low values at low frequencies region and then an increase with frequency due to short-range mobility of charge carriers. While the value of M‧ increase with increasing frequency, the value of M″ shows two peak and the peaks positions shifts to higher frequency with increasing applied voltage due to the decrease of the polarization and Nss effects with increasing frequency.

  15. A Novel Inductor-less DC-AC Cascaded H-bridge Multilevel Boost Inverter for Electric/Hybrid Electric Vehicle Applications

    SciTech Connect

    Du, Zhong; Ozpineci, Burak; Tolbert, Leon M; Chiasson, John N

    2007-01-01

    This paper presents an inductorless cascaded H- bridge multilevel boost inverter for EV and HEV applications. Currently available power inverter systems for HEVs use a DC- DC boost converter to boost the battery voltage for a traditional 3-phase inverter. The present HEV traction drive inverters have low power density, are expensive, and have low efficiency because they need a bulky inductor. An inductorless cascaded H-bridge multilevel boost inverter for EV and HEV applications is proposed in this paper. Traditionally, each H-bridge needs a DC power supply. The proposed inductorless cascaded H-bridge multilevel boost inverter uses a standard 3-leg inverter (one leg for each phase) and an H-bridge in series with each inverter leg which uses a capacitor as the DC power source. Fundamental switching scheme is used to do modulation control and to produce a 5-level phase voltage. Experiments show that the proposed inductorless DC-AC cascaded H-bridge multilevel boost inverter can output a boosted AC voltage.

  16. Impact of real world driving pattern and all-electric range on battery sizing and cost of plug-in hybrid electric two-wheeler

    NASA Astrophysics Data System (ADS)

    Amjad, Shaik; Rudramoorthy, R.; Neelakrishnan, S.; Varman, K. Sri Raja; Arjunan, T. V.

    2011-03-01

    This study addresses the impact of an actual drive pattern on the sizing and cost of a battery pack for a plug-in hybrid electric two-wheeler. To estimate the daily average travel distance in fixing the all-electric range of two wheelers, a study conducted in Coimbatore city is presented. A MATLAB simulation model developed for estimating the energy and power requirements in an all-electric strategy using an Indian driving cycle (IDC) and a real-world driving pattern are discussed. The simulation results reveal the impact of the real-world driving pattern on energy consumption and also the influence of all-electric range in sizing the battery pack. To validate the results, a plug-in hybrid electric two-wheeler developed by modifying a standard two-wheeler has been tested on the road with the help of the IDC simulator kit. An annual battery cost comparison shows that nickel-metal-hydride batteries are more economical and suitable for in plug-in hybrid electric two-wheelers.

  17. Mechanical design and driving mechanism of an isokinetic functional electrical stimulation-based leg stepping trainer.

    PubMed

    Hamzaid, N A; Fornusek, C; Ruys, A; Davis, G M

    2007-12-01

    The mechanical design of a constant velocity (isokinetic) leg stepping trainer driven by functional electrical stimulation-evoked muscle contractions was the focus of this paper. The system was conceived for training the leg muscles of neurologically-impaired patients. A commercially available slider crank mechanism for elliptical stepping exercise was adapted to a motorized isokinetic driving mechanism. The exercise system permits constant-velocity pedalling at cadences of 1-60 rev x min(-1). The variable-velocity feature allows low pedalling forces for individuals with very weak leg muscles, yet provides resistance to higher pedalling effort in stronger patients. In the future, the system will be integrated with a computer-controlled neuromuscular stimulator and a feedback control unit to monitor training responses of spinal cord-injured, stroke and head injury patients.

  18. Mechanical design and driving mechanism of an isokinetic functional electrical stimulation-based leg stepping trainer.

    PubMed

    Hamzaid, N A; Fornusek, C; Ruys, A; Davis, G M

    2007-12-01

    The mechanical design of a constant velocity (isokinetic) leg stepping trainer driven by functional electrical stimulation-evoked muscle contractions was the focus of this paper. The system was conceived for training the leg muscles of neurologically-impaired patients. A commercially available slider crank mechanism for elliptical stepping exercise was adapted to a motorized isokinetic driving mechanism. The exercise system permits constant-velocity pedalling at cadences of 1-60 rev x min(-1). The variable-velocity feature allows low pedalling forces for individuals with very weak leg muscles, yet provides resistance to higher pedalling effort in stronger patients. In the future, the system will be integrated with a computer-controlled neuromuscular stimulator and a feedback control unit to monitor training responses of spinal cord-injured, stroke and head injury patients. PMID:18274073

  19. Prospects for the application of GaN power devices in hybrid electric vehicle drive systems

    NASA Astrophysics Data System (ADS)

    Su, Ming; Chen, Chingchi; Rajan, Siddharth

    2013-07-01

    GaN, a wide bandgap semiconductor successfully implemented in optical and high-speed electronic devices, has gained momentum in recent years for power electronics applications. Along with rapid progress in material and device processing technologies, high-voltage transistors over 600 V have been reported by a number of teams worldwide. These advances make GaN highly attractive for the growing market of electrified vehicles, which currently employ bipolar silicon devices in the 600-1200 V class for the traction inverter. However, to capture this billion-dollar power market, GaN has to compete with existing IGBT products and deliver higher performance at comparable or lower cost. This paper reviews key achievements made by the GaN semiconductor industry, requirements of the automotive electric drive system and remaining challenges for GaN power devices to fit in the inverter application of hybrid vehicles.

  20. Physical and electrical models for interpreting AC and DC transport measurements in polymer solar cells

    NASA Astrophysics Data System (ADS)

    McIntyre, Max; Tzolov, Marian; Cossel, Raquel; Peeler, Seth

    We have fabricated and studied bulk heterojunction solar cells using a mixture of the low bandgap material PCPDTBT and PCBM-C60. Our transport studies show that the devices in dark have good rectification and they respond to AC voltage as a simple RC circuit. The illumination causes an additional contribution to the impedance, which varies with the level of illumination. One proposed model is that photo-generated charges can become trapped in potential wells. These charges then follow a Debye relaxation process, which contributes to a varying dielectric constant. Another proposed model is based on a RC circuit model with two capacitors which can describe the varying capacitance behavior. The physical mechanism for this model is that photo-generated charges become accumulated at the interface between PCPDTBT and PCBM-C60 and form an additional layer of charge. We will show that our circuit models and their analogous physical models can predict the AC and DC responses of polymer solar cells.

  1. Some AC electrical properties of Li-Mg ferrites[Alternating Current

    SciTech Connect

    Bellad, S.S.; Watawe, S.C.; Chougule, B.K.

    1999-05-01

    The ac resistivity ({rho}{sub ac}), dielectric constant ({epsilon}{prime}), dielectric loss tangent (tan {delta}) and initial permeability ({mu}{sub i}) of mixed Li{sub 0.5{minus}x/2}Mg{sub x}Fe{sub 2.5{minus}x/2}O{sub 4} (where x = 0.1, 0.2, 0.3, 0.4, 0.5, and 0.6) ferrite system were measured at room temperature as a function of frequency in the range from 1 kHz to 1 MHz. The resistivity of all the samples decreased with increase in frequency, indicating that the samples exhibited normal ferrimagnetic behavior. The compositional variation of resistivity and dielectric constant indicated the inverse trends of each other. The sample with x = 0.3 showed the lowest resistivity and the highest dielectric constant. The dielectric loss tangent showed maxima at 3 kHz for x = 0.2 samples and at 15--20 kHz for x = 0.3 and 0.4 samples. All of the variations are explained on the basis of Fe{sup 2+}/Fe{sup 3+} ion concentration on octahedral sites as well as the electronic hopping frequency between Fe{sup 2+} {leftrightarrow} Fe{sup 3+} ions.

  2. Planar micro-nano-coils for electrically driving liquid crystal microlenses based on wireless power transmission

    NASA Astrophysics Data System (ADS)

    Chen, Cheng; Hu, Wei; Luo, Jun; Lei, Yu; Tong, Qing; Zhang, Xinyu; Sang, Hongshi; Xie, Changsheng

    2015-12-01

    In this paper, the planar micro-nano-coils (PMNCs) with diverse planar spiral structures are designed for electrically driving and controlling liquid crystal microlenses (LCMs) based on wireless power transmission approaches. The PMNCs with different basic shapes are fabricated, including typical micro-triangle, micro-square, micro-pentagon, micro-hexagon, and micro-circle. According to the designed microstructures, using loop iterative approximation means based on Greenhouse algorithm, the inductance values of the microcoils can be calculated through combining self-inductance with mutual-inductance. In experiments, both the wet and dry etching technologies are adapted to obtain the desired PMNCs over aluminum-coated glass substrates. The etching technologies utilized by us are implemented on initial glass substrates spread by photoresist mask, which has been processed by common ultraviolet lithography. And the wet and dry etching technologies are different in the way of eroding aluminum film. Usually, the wet etching is a kind of the chemical reaction of alkali element in the developing liquid used, but the dry etching is a type of physical etching process such as the ion beam etching so as to fabricate microstructures with smaller size than that of wet etching. After the fabrication of the PMNCs, the electrical testing circuit for the inductance of the PMNCs is built to obtain their actual inductance values. By comparing inductances with theoretical prediction, the improved PMNCs are proposed for driving and controlling LCMs, which demonstrates enhanced light transmission efficiency of the PMNCs, and makes it more efficient to adjust LCMs developed by us.

  3. Theoretical analysis of AC electric field transmission into biological tissue through frozen saline for electroporation.

    PubMed

    Xiao, Chunyan; Rubinsky, Boris

    2014-12-01

    An analytical model was used to explore the feasibility of sinusoidal electric field transmission across a frozen saline layer into biological tissue. The study is relevant to electroporation and permeabilization of the cell membrane by electric fields. The concept was analyzed for frequencies in the range of conventional electroporation frequencies and electric field intensity. Theoretical analysis for a variety of tissues show that the transmission of electroporation type electric fields through a layer of frozen saline into tissue is feasible and the behavior of this composite system depends on tissue type, frozen domain temperature, and frequency. Freezing could become a valuable method for adherence of electroporation electrodes to moving tissue surfaces, such as the heart in the treatment of atrial fibrillation or blood vessels for the treatment of restenosis.

  4. Physics-Based Modeling of Electric Operation, Heat Transfer, and Scrap Melting in an AC Electric Arc Furnace

    NASA Astrophysics Data System (ADS)

    Opitz, Florian; Treffinger, Peter

    2016-04-01

    Electric arc furnaces (EAF) are complex industrial plants whose actual behavior depends upon numerous factors. Due to its energy intensive operation, the EAF process has always been subject to optimization efforts. For these reasons, several models have been proposed in literature to analyze and predict different modes of operation. Most of these models focused on the processes inside the vessel itself. The present paper introduces a dynamic, physics-based model of a complete EAF plant which consists of the four subsystems vessel, electric system, electrode regulation, and off-gas system. Furthermore the solid phase is not treated to be homogenous but a simple spatial discretization is employed. Hence it is possible to simulate the energy input by electric arcs and fossil fuel burners depending on the state of the melting progress. The model is implemented in object-oriented, equation-based language Modelica. The simulation results are compared to literature data.

  5. Structural, Optical and AC Electrical Properties of Ce3+-Doped TiO2-SiO2 Matrices

    NASA Astrophysics Data System (ADS)

    Vidyadharan, Viji; Vasudevan, Prathibha; Karthika, S.; Joseph, Cyriac; Unnikrishnan, N. V.; Biju, P. R.

    2015-08-01

    We report the structural, photoluminescence and alternating current (AC) electrical properties of Ce3+-doped titanosilicate matrices prepared by nonhydrolytic sol-gel method, with different annealing temperatures. The structural characterization of the prepared samples was done by x-ray diffraction, energy dispersive spectrum and Fourier transform infrared spectroscopy measurements. The thermal stability of the prepared matrices was studied by the differential scanning calorimetric analysis. The photoluminescence spectrum shows two luminescence bands centered at 360 nm and 464 nm corresponding to the transitions 2D3/2 to 2F7/2 and 2F5/2, respectively. The dielectric responses of the samples were investigated for the frequency range 1 kHz-3 MHz at room temperature. The variation of AC conductivity, real part of dielectric constant ɛ' and imaginary part of dielectric constant ɛ″ with frequency were also studied. The Cole-Cole parameters were calculated and the semicircles observed in the plots indicate a single relaxation process which can be modelled by an equivalent parallel resistor-capacitor circuit.

  6. Composite rod insulators for ac power lines; Electrical performance of various designs at a coastal testing station

    SciTech Connect

    Houlgate, R.G.; Swift, D.A. )

    1990-10-01

    The electrical performance of thirty-six composite insulators - of four commercial types for each AC system level of 34.5 kV, 230 kV and 500 kV - has been determined at the CEGB insulator testing station, Brighton, England. The weathershed materials were epoxy-resin, ethylene propylene rubber and silicone rubber; half of the 230 kV insulators had no stress rings. Surface leakage current was recorded for surge levels of 25 mA, 150 mA and 500 mA; a special technique was developed to obtain the flashover statistics of the 500 kV insulators, thereby enabling performance of the composite insulator to be quantified relative to that of a string of cap and pin porcelain insulators of anti-fog design, the deterioration of the insulators was observed by making regular visual inspections. The practical consequences of the findings and the causes of the degradation are discussed.

  7. AC electric field induced dielectrophoretic assembly behavior of gold nanoparticles in a wide frequency range

    NASA Astrophysics Data System (ADS)

    Liu, Weiyu; Wang, Chunhui; Ding, Haitao; Shao, Jinyou; Ding, Yucheng

    2016-05-01

    In this work, we focus on frequency-dependence of pearl chain formations (PCF) of gold nanoparticles driven by AC dielectrophoresis (DEP), especially in a low field-frequency range, where induced double-layer charging effect at ideally polarizable surfaces on particle DEP behavior and surrounding liquid motion need not be negligible. As field frequency varies, grown features of DEP assembly structures ranging from low-frequency non-bridged gap to high-frequency single gold nanoparticle-made nanowires bridging the electrodes are demonstrated experimentally. Specifically, at 10 kHz, a kind of novel channel-like structure with parallel opposing banks is formed at the center of interelectrode gap. In stark contrast, at 1 MHz, thin PCF with diameter of 100 nm is created along the shortest distance of the isolation spacing. Moreover, a particular conductive path of nanoparticle chains is produced at 1 MHz in a DEP device embedded with multiple floating electrodes. A theoretical framework taking into account field-induced double-layer polarization at both the particle/electrolyte and electrode/electrolyte interface is developed to correlate these experimental observations with induced-charge electrokinetic (ICEK) phenomenon. And a RC circuit model is helpful in accounting for the formation of this particular non-bridged channel-like structure induced by a low-frequency AC voltage. As compared to thin PCF formed at high field frequency that effectively short circuits the electrode pair, though it is difficult for complete PCF bridging to occur at low frequency, the non-bridged conducting microstructure has potential to further miniaturize the size of electrode gap fabricated by standard micromachining process and may find useful application in biochemical sensing.

  8. Time dependence of electrical bioimpedance on porcine liver and kidney under a 50 Hz ac current.

    PubMed

    Spottorno, J; Multigner, M; Rivero, G; Alvarez, L; de la Venta, J; Santos, M

    2008-03-21

    The purpose of this work is to study the changes of the bioimpedance from its 'in vivo' value to the values measured in a few hours after the excision from the body. The evolution of electrical impedance with time after surgical extraction has been studied on two porcine organs: the liver and the kidney. Both in vivo and ex vivo measurements of electrical impedance, measuring its real and imaginary components, have been performed. The in vivo measurements have been carried out with the animal anaesthetized. The ex vivo measurements have been made more than 2 h after the extraction of the organ. The latter experiment has been carried out at two different stabilized temperatures: at normal body temperature and at the standard preservation temperature for transplant surgery. The measurements show a correlation between the biological evolution and the electrical bioimpedance of the organs, which increases from its in vivo value immediately after excision, multiplying its value by 2 in a few hours.

  9. Simulation and mathematical analyses of AC electric field driven apoptosis via microtubule disintegration

    NASA Astrophysics Data System (ADS)

    Tiwari, Pawan K.

    2015-09-01

    The moderate intensity alternating current electric fields with frequencies ranging between a few tens of kilohertz and a few tens of megahertz, also known as tumor treating fields (TTFs) are utilized as a modality in the electrotherapeutic treatment of the cancer cells. The application of sub-MHz TTF on the cancer cell results in the inducement of higher electric field at the furrow between the daughter cells, and such apoptosis stimulating phenomenon is investigated through the Maxwell two-dimensional (2D) finite element simulations. A furrow distance of the order of size of the nucleus accounts for the intense electric field inducement disintegrating the microtubule via the processes of its surface disruption and tubulin dimer detachment. A simulation and mathematical analyses of the microtubule disintegration mechanism is formulated to ascertain one of the factors causing an apoptosis of the cancer cells, and consequently checking their proliferation.

  10. Electrical Experiments. VT-214-12-2. Part II. A-C Across the Line Control.

    ERIC Educational Resources Information Center

    Connecticut State Dept. of Education, Hartford. Div. of Vocational Education.

    Designed for high school electronics students, this second document in a series of six electrical learning activity packages focuses on alternating current across-the-line control. An introductory section gives the objective for the activities, an introduction, and an outline of the content. The remainder of the activity book is comprised of…

  11. Destruction of Emulsions by an AC Electric Field: Importance of Partial Merging

    NASA Astrophysics Data System (ADS)

    Thiam, Abdou Rachid; Bremond, Nicolas; Bibette, Jerome

    2010-03-01

    Electrocoalescence is basically the process of blending droplets by the application of an electric field. The approach is used in petroleum refineries for the separation of water in oil emulsions (that is, by coalescing water droplets), and more recently in biotechnology industry, for the fusion of micro reactors. In a first step, we will focus on the coalesce condition for two drops under a given electric field. Microfluidics offers a comfortable setup therefore, as we sought to span a range of initial conditions in terms of the distance between the droplets, their sizes, and also a region of the applied electric field. Thus, we could establish a stability diagram according to the initial conditions and droplets' composition, which displays three domains referred to as: coalescence, no coalescence and a third one of partial coalescence, where the droplets coalesce for a brief moment then separate right afterwards. We proceeded then by generalizing the setup to the case of a stream of droplets, and we found that the evolution of the stream can be predicted by the behaviour of the local pairs of droplets, as seen in the previous step. The main outcome of that study is the total destruction of an emulsion above a critical volume fraction for a given amplitude of electric field.

  12. Electrical Experiments. VT-214-12-4. Part IV. A-C Reduced Voltage Controls.

    ERIC Educational Resources Information Center

    Connecticut State Dept. of Education, Hartford. Div. of Vocational Education.

    Designed for high school electronics students, this fourth document in a series of six electrical learning activity packages focuses on alternating current-reduced voltage controls. An introductory section gives the objective for the activities, an introduction, and an outline of the content. The remainder of the guidebook is comprised of…

  13. Converting a commercial electric direct-drive robot to operate from joint torque commands

    SciTech Connect

    Muir, P.F.

    1991-07-01

    Many robot control algorithms for high performance in-contact operations including hybrid force/position, stiffness control and impedance control approaches require the command the joint torques. However, most commercially available robots do not provide joint torque command capabilities. The joint command at the user level is typically position or velocity and at the control developer level is voltage, current, or pulse-width, and the torque generated is a nonlinear function of the command and joint position. To enable the application of high performance in-contact control algorithms to commercially available robots, and thereby facilitate technology transfer from the robot control research community to commercial applications, an methodology has been developed to linearize the torque characteristics of electric motor-amplifier combinations. A four degree of freedom Adept 2 robot, having pulse-width modulation amplifiers and both variable reluctance and brushless DC motors, is converted to operate from joint torque commands to demonstrate the methodology. The commercial robot controller is replaced by a VME-based system incorporating special purpose hardware and firmware programmed from experimental data. The performance improvement is experimentally measured and graphically displayed using three-dimensional plots of torque vs command vs position. The average percentage torque deviation over the command and position ranges is reduced from as much as 76% to below 5% for the direct-drive joints 1, 2 and 4 and is cut by one half in the remaining ball-screw driven joint 3. Further, the torque deviation of the direct-drive joints drops below 2.5% if only the upper 90% of the torque range is considered. 23 refs., 20 figs., 2 tabs.

  14. Changes of Excitability in M1 Induced by Neuromuscular Electrical Stimulation Differ Between Presence and Absence of Voluntary Drive

    ERIC Educational Resources Information Center

    Sugawara, Kenichi; Tanabe, Shigeo; Higashi, Toshio; Tsurumi, Takamasa; Kasai, Tatsuya

    2011-01-01

    The aim of this study is to investigate excitability changes in the human motor cortex induced by variable therapeutic electrical stimulations (TESs) with or without voluntary drive. We recorded motor-evoked potentials (MEPs) from extensor and flexor carpi radialis (FCR) muscles at rest and during FCR muscle contraction after the application of…

  15. Frequency-dependent electrodeformation of giant phospholipid vesicles in AC electric field

    PubMed Central

    2010-01-01

    A model of vesicle electrodeformation is described which obtains a parametrized vesicle shape by minimizing the sum of the membrane bending energy and the energy due to the electric field. Both the vesicle membrane and the aqueous media inside and outside the vesicle are treated as leaky dielectrics, and the vesicle itself is modeled as a nearly spherical shape enclosed within a thin membrane. It is demonstrated (a) that the model achieves a good quantitative agreement with the experimentally determined prolate-to-oblate transition frequencies in the kilohertz range and (b) that the model can explain a phase diagram of shapes of giant phospholipid vesicles with respect to two parameters: the frequency of the applied alternating current electric field and the ratio of the electrical conductivities of the aqueous media inside and outside the vesicle, explored in a recent paper (S. Aranda et al., Biophys J 95:L19–L21, 2008). A possible use of the frequency-dependent shape transitions of phospholipid vesicles in conductometry of microliter samples is discussed. PMID:21886342

  16. Direct simulation of phase delay effects on induced-charge electro-osmosis under large ac electric fields.

    PubMed

    Sugioka, Hideyuki

    2016-08-01

    The standard theory of induced-charge electro-osmosis (ICEO) often overpredicts experimental values of ICEO velocities. Using a nonsteady direct multiphysics simulation technique based on the coupled Poisson-Nernst-Planck and Stokes equations for an electrolyte around a conductive cylinder subject to an ac electric field, we find that a phase delay effect concerning an ion response provides a fundamental mechanism for electrokinetic suppression. A surprising aspect of our findings is that the phase delay effect occurs even at much lower frequencies (e.g., 50 Hz) than the generally believed charging frequency of an electric double layer (typically, 1 kHz) and it can decrease the electrokinetic velocities in one to several orders. In addition, we find that the phase delay effect may also cause a change in the electrokinetic flow directions (i.e., flow reversal) depending on the geometrical conditions. We believe that our findings move toward a more complete understanding of complex experimental nonlinear electrokinetic phenomena.

  17. Direct simulation of phase delay effects on induced-charge electro-osmosis under large ac electric fields

    NASA Astrophysics Data System (ADS)

    Sugioka, Hideyuki

    2016-08-01

    The standard theory of induced-charge electro-osmosis (ICEO) often overpredicts experimental values of ICEO velocities. Using a nonsteady direct multiphysics simulation technique based on the coupled Poisson-Nernst-Planck and Stokes equations for an electrolyte around a conductive cylinder subject to an ac electric field, we find that a phase delay effect concerning an ion response provides a fundamental mechanism for electrokinetic suppression. A surprising aspect of our findings is that the phase delay effect occurs even at much lower frequencies (e.g., 50 Hz) than the generally believed charging frequency of an electric double layer (typically, 1 kHz) and it can decrease the electrokinetic velocities in one to several orders. In addition, we find that the phase delay effect may also cause a change in the electrokinetic flow directions (i.e., flow reversal) depending on the geometrical conditions. We believe that our findings move toward a more complete understanding of complex experimental nonlinear electrokinetic phenomena.

  18. Direct simulation of phase delay effects on induced-charge electro-osmosis under large ac electric fields.

    PubMed

    Sugioka, Hideyuki

    2016-08-01

    The standard theory of induced-charge electro-osmosis (ICEO) often overpredicts experimental values of ICEO velocities. Using a nonsteady direct multiphysics simulation technique based on the coupled Poisson-Nernst-Planck and Stokes equations for an electrolyte around a conductive cylinder subject to an ac electric field, we find that a phase delay effect concerning an ion response provides a fundamental mechanism for electrokinetic suppression. A surprising aspect of our findings is that the phase delay effect occurs even at much lower frequencies (e.g., 50 Hz) than the generally believed charging frequency of an electric double layer (typically, 1 kHz) and it can decrease the electrokinetic velocities in one to several orders. In addition, we find that the phase delay effect may also cause a change in the electrokinetic flow directions (i.e., flow reversal) depending on the geometrical conditions. We believe that our findings move toward a more complete understanding of complex experimental nonlinear electrokinetic phenomena. PMID:27627362

  19. Energy analysis of electric vehicles using batteries or fuel cells through well-to-wheel driving cycle simulations

    NASA Astrophysics Data System (ADS)

    Campanari, Stefano; Manzolini, Giampaolo; Garcia de la Iglesia, Fernando

    This work presents a study of the energy and environmental balances for electric vehicles using batteries or fuel cells, through the methodology of the well to wheel (WTW) analysis, applied to ECE-EUDC driving cycle simulations. Well to wheel balances are carried out considering different scenarios for the primary energy supply. The fuel cell electric vehicles (FCEV) are based on the polymer electrolyte membrane (PEM) technology, and it is discussed the possibility to feed the fuel cell with (i) hydrogen directly stored onboard and generated separately by water hydrolysis (using renewable energy sources) or by conversion processes using coal or natural gas as primary energy source (through gasification or reforming), (ii) hydrogen generated onboard with a fuel processor fed by natural gas, ethanol, methanol or gasoline. The battery electric vehicles (BEV) are based on Li-ion batteries charged with electricity generated by central power stations, either based on renewable energy, coal, natural gas or reflecting the average EU power generation feedstock. A further alternative is considered: the integration of a small battery to FCEV, exploiting a hybrid solution that allows recovering energy during decelerations and substantially improves the system energy efficiency. After a preliminary WTW analysis carried out under nominal operating conditions, the work discusses the simulation of the vehicles energy consumption when following standardized ECE-EUDC driving cycle. The analysis is carried out considering different hypothesis about the vehicle driving range, the maximum speed requirements and the possibility to sustain more aggressive driving cycles. The analysis shows interesting conclusions, with best results achieved by BEVs only for very limited driving range requirements, while the fuel cell solutions yield best performances for more extended driving ranges where the battery weight becomes too high. Results are finally compared to those of conventional internal

  20. The complete frequency spectrum of physiological tremor can be recreated by broadband mechanical or electrical drive.

    PubMed

    Vernooij, Carlijn Andrea; Lakie, Martin; Reynolds, Raymond Francis

    2015-01-15

    Two frequency peaks of variable preponderance have been reported for human physiological finger tremor. The high-frequency peak (20-25 Hz, seen only in postural tremor) is generally attributed to mechanical resonance, whereas the lower frequency peak (8-12 Hz, seen in both postural and kinetic tremor) is usually attributed to synchronous central or reflexive neural drive. In this study, we determine whether mechanical resonance could generate both peaks. In relaxed subjects, an artificial finger tremor was evoked by random mechanical perturbations of the middle finger or random electrical muscular stimulation of the finger extensor muscle. The high and the low frequencies observed in physiological tremor could both be created by either type of artificial input at appropriate input intensity. Resonance, inferred from cross-spectral gain and phase, occurred at both frequencies. To determine any neural contribution, we compared truly passive subjects with those who exhibited some electromyographic (EMG) activity in the finger extensor; artificially created tremor spectra were almost identical between groups. We also applied electrical stimuli to two clinically deafferented subjects lacking stretch reflexes. They exhibited the same artificial tremor spectrum as control subjects. These results suggest that both typical physiological finger tremor frequencies can be reproduced by random artificial input; neither requires synchronized neural input. We therefore suggest that mechanical resonance could generate both dominant frequency peaks characteristic of physiological finger tremor. The inverse relationship between the input intensity and the resulting tremor frequency can be explained by a movement-dependent reduction in muscle stiffness, a conjecture we support using a simple computational model. PMID:25376782

  1. Influence of electrical fields (AC and DC) on phytoremediation of metal polluted soils with rapeseed (Brassica napus) and tobacco (Nicotiana tabacum).

    PubMed

    Bi, Ran; Schlaak, Michael; Siefert, Eike; Lord, Richard; Connolly, Helen

    2011-04-01

    The combined use of electrokinetic remediation and phytoremediation to decontaminate soil polluted with heavy metals has been demonstrated in a laboratory-scale experiment. The plants species selected were rapeseed and tobacco. Three kinds of soil were used: un-contaminated soil from forest area (S1), artificially contaminated soil with 15mgkg(-1) Cd (S2) and multi-contaminated soil with Cd, Zn and Pb from an industrial area (S3). Three treatment conditions were applied to the plants growing in the experimental vessels: control (no electrical field), alternating current electrical field (AC, 1Vcm(-1)) and direct current electrical field (DC, 1Vcm(-1)) with switching polarity every 3h. The electrical fields were applied for 30d for rapeseed and 90d for tobacco, each experiment had three replicates. After a total of 90d growth for rapeseed and of 180d for tobacco, the plants were harvested. The pH variation from anode to cathode was eliminated by switching the polarity of the DC field. The plants reacted differently under the applied electrical field. Rapeseed biomass was enhanced under the AC field and no negative effect was found under DC field. However, no enhancement of the tobacco biomass under the AC treatment was found. The DC field had a negative influence on biomass production on tobacco plants. In general, Cd content was higher in both species growing in S2 treated with AC field compared to the control. Metal uptake (Cd, Cu, Zn and Pb) per rapeseed plant shoot was enhanced by the application of AC field in all soils. PMID:21237480

  2. Study of the Advantages of Internal Permanent Magnet Drive Motor with Selectable Windings for Hybrid-Electric Vehicles

    SciTech Connect

    Otaduy, P.J.; Hsu, J.S.; Adams, D.J.

    2007-11-30

    This report describes research performed on the viability of changing the effectively active number of turns in the stator windings of an internal permanent magnet (IPM) electric motor to strengthen or weaken the magnetic fields in order to optimize the motor's performance at specific operating speeds and loads. Analytical and simulation studies have been complemented with research on switching mechanisms to accomplish the task. The simulation studies conducted examine the power and energy demands on a vehicle following a series of standard driving cycles and the impact on the efficiency and battery size of an electrically propelled vehicle when it uses an IPM motor with turn-switching capabilities. Both full driving cycle electric propulsion and propulsion limited starting from zero to a set speed have been investigated.

  3. High power ac/dc variable R dynamic electrical load simulator

    NASA Technical Reports Server (NTRS)

    Joncas, K. P.

    1974-01-01

    A study program was undertaken to investigate various concepts and techniques for identifying and simulating both the steady-state and dynamic characteristics of electrical loads for use during integrated system test and evaluation. The development of hardware capable of providing the simulation capability is discussed. A general purpose simulator was developed with the capability of realizing a variety of models where element values were discretely variable. The different models, each corresponding to real spacecraft equipment, are set up manually for each case by suitable switching and patching. The models are capable of duplicating the dynamic and steady-state response of real loads at full power.

  4. Tools for Designing Thermal Management of Batteries in Electric Drive Vehicles (Presentation)

    SciTech Connect

    Pesaran, A.; Keyser, M.; Kim, G. H.; Santhanagopalan, S.; Smith, K.

    2013-02-01

    Temperature has a significant impact on life, performance, and safety of lithium-ion battery technology, which is expected to be the energy storage of choice for electric drive vehicles (xEVs). High temperatures degrade Li-ion cells faster while low temperatures reduce power and energy capabilities that could have cost, reliability, range, or drivability implications. Thermal management of battery packs in xEVs is essential to keep the cells in the desired temperature range and also reduce cell-to-cell temperature variations, both of which impact life and performance. The value that the battery thermal management system provides in reducing battery life and improving performance outweighs its additional cost and complexity. Tools that are essential for thermal management of batteries are infrared thermal imaging, isothermal calorimetry, thermal conductivity meter and computer-aided thermal analysis design software. This presentation provides details of these tools that NREL has used and we believe are needed to design right-sized battery thermal management systems.

  5. Driving and controlling molecular surface rotors with a terahertz electric field.

    PubMed

    Neumann, Jan; Gottschalk, Kay E; Astumian, R Dean

    2012-06-26

    Great progress has been made in the design and synthesis of molecular motors and rotors. Loosely inspired by biomolecular machines such as kinesin and the FoF1 ATPsynthase, these molecules are hoped to provide elements for construction of more elaborate structures that can carry out tasks at the nanoscale corresponding to the tasks accomplished by elementary machines in the macroscopic world. Most of the molecular motors synthesized to date suffer from the drawback that they operate relatively slowly (less than kHz). Here we show by molecular dynamics studies of a diethyl sulfide rotor on a gold(111) surface that a high-frequency oscillating electric field normal to the surface can drive directed rotation at GHz frequencies. The maximum directed rotation rate is 10(10) rotations per second, significantly faster than the rotation of previously reported directional molecular rotors. Understanding the fundamental basis of directed motion of surface rotors is essential for the further development of efficient externally driven artificial rotors. Our results represent a step toward the design of a surface-bound molecular rotary motor with a tunable rotation frequency and direction. PMID:22574650

  6. Hazard detection in noise-related incidents - the role of driving experience with battery electric vehicles.

    PubMed

    Cocron, Peter; Bachl, Veronika; Früh, Laura; Koch, Iris; Krems, Josef F

    2014-12-01

    The low noise emission of battery electric vehicles (BEVs) has led to discussions about how to address potential safety issues for other road users. Legislative actions have already been undertaken to implement artificial sounds. In previous research, BEV drivers reported that due to low noise emission they paid particular attention to pedestrians and bicyclists. For the current research, we developed a hazard detection task to test whether drivers with BEV experience respond faster to incidents, which arise due to the low noise emission, than inexperienced drivers. The first study (N=65) revealed that BEV experience only played a minor role in drivers' response to hazards resulting from low BEV noise. The tendency to respond, reaction times and hazard evaluations were similar among experienced and inexperienced BEV drivers; only small trends in the assumed direction were observed. Still, both groups clearly differentiated between critical and non-critical scenarios and responded accordingly. In the second study (N=58), we investigated additionally if sensitization to low noise emission of BEVs had an effect on hazard perception in incidents where the noise difference is crucial. Again, participants in all groups differentiated between critical and non-critical scenarios. Even though trends in response rates and latencies occurred, experience and sensitization to low noise seemed to only play a minor role in detecting hazards due to low BEV noise. An additional global evaluation of BEV noise further suggests that even after a short test drive, the lack of noise is perceived more as a comfort feature than a safety threat.

  7. Resonant snubber based soft-switching inverters for electric propulsion drives

    SciTech Connect

    Lai, J.S.

    1996-05-01

    This paper summarizes recently developed soft-switching inverters and proposes two alternative options for electric propulsion drives. The newly developed soft-switching inverter employs an auxiliary switch and a resonant inductor per phase to produce a zero voltage across the main switch so that the main switch can turn on at the zero-voltage condition. Both the auxiliary switch and the resonant inductor are operating at a fractional duty, and thus are small in size as compared to the main inverter circuit components. Operation modes in a complete zero-voltage switching cycle for the single-phase soft-switching inverter are described in detail with graphical explanations. The circuit operation was first verified by a computer simulation and then tested with an 1-kW single-phase and an 100-kW three-phase inverters. Experimental results are presented to show the superior performance in efficiency improvement, EMI reduction, and dv/dt reduction of the proposed soft-switching inverters.

  8. Direct activation of the Mauthner cell by electric field pulses drives ultrarapid escape responses

    PubMed Central

    Tabor, Kathryn M.; Bergeron, Sadie A.; Horstick, Eric J.; Jordan, Diana C.; Aho, Vilma; Porkka-Heiskanen, Tarja; Haspel, Gal

    2014-01-01

    Rapid escape swims in fish are initiated by the Mauthner cells, giant reticulospinal neurons with unique specializations for swift responses. The Mauthner cells directly activate motoneurons and facilitate predator detection by integrating acoustic, mechanosensory, and visual stimuli. In addition, larval fish show well-coordinated escape responses when exposed to electric field pulses (EFPs). Sensitization of the Mauthner cell by genetic overexpression of the voltage-gated sodium channel SCN5 increased EFP responsiveness, whereas Mauthner ablation with an engineered variant of nitroreductase with increased activity (epNTR) eliminated the response. The reaction time to EFPs is extremely short, with many responses initiated within 2 ms of the EFP. Large neurons, such as Mauthner cells, show heightened sensitivity to extracellular voltage gradients. We therefore tested whether the rapid response to EFPs was due to direct activation of the Mauthner cells, bypassing delays imposed by stimulus detection and transmission by sensory cells. Consistent with this, calcium imaging indicated that EFPs robustly activated the Mauthner cell but only rarely fired other reticulospinal neurons. Further supporting this idea, pharmacological blockade of synaptic transmission in zebrafish did not affect Mauthner cell activity in response to EFPs. Moreover, Mauthner cells transgenically expressing a tetrodotoxin (TTX)-resistant voltage-gated sodium channel retained responses to EFPs despite TTX suppression of action potentials in the rest of the brain. We propose that EFPs directly activate Mauthner cells because of their large size, thereby driving ultrarapid escape responses in fish. PMID:24848468

  9. AC electric field for rapid assembly of nanostructured polyaniline onto microsized gap for sensor devices.

    PubMed

    La Ferrara, Vera; Rametta, Gabriella; De Maria, Antonella

    2015-07-01

    Interconnected network of nanostructured polyaniline (PANI) is giving strong potential for enhancing device performances than bulk PANI counterparts. For nanostructured device processing, the main challenge is to get prototypes on large area by requiring precision, low cost and high rate assembly. Among processes meeting these requests, the alternate current electric fields are often used for nanostructure assembling. For the first time, we show the assembly of nanostructured PANI onto large electrode gaps (30-60 μm width) by applying alternate current electric fields, at low frequencies, to PANI particles dispersed in acetonitrile (ACN). An important advantage is the short assembly time, limited to 5-10 s, although electrode gaps are microsized. That encouraging result is due to a combination of forces, such as dielectrophoresis (DEP), induced-charge electrokinetic (ICEK) flow and alternate current electroosmotic (ACEO) flow, which speed up the assembly process when low frequencies and large electrode gaps are used. The main achievement of the present study is the development of ammonia sensors created by direct assembling of nanostructured PANI onto electrodes. Sensors exhibit high sensitivity to low gas concentrations as well as excellent reversibility at room temperature, even after storage in air.

  10. Electrical Characteristics, Electrode Sheath and Contamination Layer Behavior of a Meso-Scale Premixed Methane-Air Flame Under AC/DC Electric Fields

    NASA Astrophysics Data System (ADS)

    Chen, Qi; Yan, Limin; Zhang, Hao; Li, Guoxiu

    2016-05-01

    Electrical characteristics of a nozzle-attached meso-scale premixed methane-air flame under low-frequency AC (0-4300 V, 0-500 Hz) and DC (0-3300 V) electric fields were studied. I-V curves were measured under different experimental conditions to estimate the magnitude of the total current 100-102 μA, the electron density 1015-1016 m-3 and further the power dissipation ≤ 0.7 W in the reaction zone. At the same time, the meso-scale premixed flame conductivity 10-4-10-3 Ω-1·m-1 as a function of voltage and frequency was experimentally obtained and was believed to represent a useful order-of magnitude estimate. Moreover, the influence of the collision sheath relating to Debye length (31-98 μm) and the contamination layer of an active electrode on measurements was discussed, based on the combination of simulation and theoretical analysis. As a result, the electrode sheath dimension was evaluated to less than 0.5 mm, which indicated a complex effect of the collision sheath on the current measurements. The surface contamination effect of an active electrode was further analyzed using the SEM imaging method, which showed elements immigration during the contamination layer formation process. supported by National Natural Science Foundation of China (No. 51376021), and the Fundamental Research Fund for Major Universities (No. 2013JBM079)

  11. Electrical Characteristics, Electrode Sheath and Contamination Layer Behavior of a Meso-Scale Premixed Methane-Air Flame Under AC/DC Electric Fields

    NASA Astrophysics Data System (ADS)

    Chen, Qi; Yan, Limin; Zhang, Hao; Li, Guoxiu

    2016-05-01

    Electrical characteristics of a nozzle-attached meso-scale premixed methane-air flame under low-frequency AC (0-4300 V, 0-500 Hz) and DC (0-3300 V) electric fields were studied. I-V curves were measured under different experimental conditions to estimate the magnitude of the total current 100-102 μA, the electron density 1015-1016 m‑3 and further the power dissipation ≤ 0.7 W in the reaction zone. At the same time, the meso-scale premixed flame conductivity 10‑4-10‑3 Ω‑1·m‑1 as a function of voltage and frequency was experimentally obtained and was believed to represent a useful order-of magnitude estimate. Moreover, the influence of the collision sheath relating to Debye length (31–98 μm) and the contamination layer of an active electrode on measurements was discussed, based on the combination of simulation and theoretical analysis. As a result, the electrode sheath dimension was evaluated to less than 0.5 mm, which indicated a complex effect of the collision sheath on the current measurements. The surface contamination effect of an active electrode was further analyzed using the SEM imaging method, which showed elements immigration during the contamination layer formation process. supported by National Natural Science Foundation of China (No. 51376021), and the Fundamental Research Fund for Major Universities (No. 2013JBM079)

  12. AC Electric Field Enhances Cryopreservation Efficiency of Sprague-Dawley Rat Liver During a Slow Freezing Procedure.

    PubMed

    Ma, Ya H; Qin, Guo F; Li, Jing; Ding, Gui R; Xu, Sheng L; Zhou, Yan; Guo, Guo Z

    2016-02-01

    Slow freezing coupled with an AC electric field (ACEF) has been demonstrated to miniaturize the ice crystals of a 0.9% (w/v) NaCl solution in a prior study. The aim of this study was to assess the effect of ACEF on Sprague-Dawley (SD) rat liver in vitro during the slow cooling procedure. SD rat liver exposed to an oscillating electric field was frozen in a programmed freezer initially down to -30°C at a cooling rate of -1°C/min and continuing down to -80°C at a cooling rate of -5°C/min. The cryovials were finally transferred into liquid nitrogen for 7 days. The frequency range was 0-20 MHz, and peak field strength was 1,000 V/m. For the sham and electric-exposed groups, the freezing solution consisted of 0%, 2.5%, 5.0%, 7.5%, or 10% (v/v) dimethyl sulfoxide (DMSO) Dulbecco's modified Eagles' medium culture solution, and fresh tissue was selected as the control group. The changes in cell survival rate, adenosine triphosphate (ATP) content, and morphology of fresh and frozen-thawed liver tissue were examined. Compared with the sham group with 5.0% DMSO, the result showed that slow freezing coupled with 2.45 MHz or 5 MHz ACEF significantly increased the relative survival rate by 43.27% and 26.31% (P < 0.001), respectively. However, ACEF exposure increased the ATP content compared with the sham group. Especially in 5% and 10% DMSO with 2.45 MHz ACEF exposure, the ATP content approximated the fresh group (7.3 ± 2.7 nmol/piece), corresponding to 94.52% and 80.82%. In addition, the cellular membrane and some organelles (e.g., mitochondria) in the electric-exposed group appeared to be more intact according to the transmission electron microscopy images. The underlying mechanism might be that the ACEF affects the formation and growth of the ice crystallization, and thus inhibits cryoinjury. These results show that ACEF would provide an efficient method for cryopreservation banking with a low concentration of CPA during the slow freezing process

  13. A novel design of DC-AC electrical machine rotary converter for hybrid solar and wind energy applications

    NASA Astrophysics Data System (ADS)

    Mohammed, K. G.; Ramli, A. Q.; Amirulddin, U. A. U.

    2013-06-01

    This paper proposes the design of a new bi-directional DC-AC rotary converter machine to convert a d.c. voltage to three-phase voltage and vice-versa using a two-stage energy conversion machine. The rotary converter consists of two main stages which are combined into single frame. These two stages are constructed from three main electromagnetic components. The first inner electromagnetic component represents the input stage that enables the DC power generated by solar energy from photo-voltaic cells to be transformed by the second and third components electro-magnetically to produce multi-phase voltages at the output stage. At the same time, extra kinetic energy from wind, which is sufficiently available, can be added to existing torque on the second electromagnetic component. Both of these input energies will add up to the final energy generated at the output terminals. Therefore, the machine will be able to convert solar and wind energies to the output terminals simultaneously. If the solar energy is low, the available wind energy will be able to provide energy to the output terminals and at the same time charges the batteries which are connected as backup system. At this moment, the machine behaves as wind turbine. The energy output from the machine benefits from two energy sources which are solar and wind. At night when the solar energy is not available and also the load is low, the wind energy is able to charge the batteries and at the same time provides output electrical power to the remaining the load. Therefore, the proposed system will have high usage of available renewable energy as compared to separated wind or solar systems. MATLAB codes are used to calculate the required dimensions, the magnetic and electrical circuits parameters to design of the new bi-directional rotary converter machine.

  14. Development and Implementation of Degree Programs in Electric Drive Vehicle Technology

    SciTech Connect

    Ng, Simon

    2013-09-30

    The Electric-drive Vehicle Engineering (EVE) MS degree and graduate certificate programs have been continuing to make good progress, thanks to the funding and the guidance from DOE grant management group, the support from our University and College administrations, and to valuable inputs and feedback from our Industrial Advisory Board as well as our project partners Macomb Community College and NextEnergy. Table 1 below lists originally proposed Statement of Project Objectives (SOPO), which have all been completed successfully. Our program and course enrollments continue to be good and increasing, as shown in later sections. Our graduating students continue to get good job offers from local EV-related companies. Following the top recommendation from our Industrial Advisory Board, we were fortunate enough to be accepted into the prestigious EcoCAR2 (http://www.ecocar2.org/) North America university design competition, and have been having some modest success with the competition. But most importantly, EcoCAR2 offers the most holistic educational environment for integrating real-world engineering and design with our EVE graduate curriculum. Such integrations include true real-world hands-on course projects based on EcoCAR2 related tasks for the students, and faculty curricular and course improvements based on lessons and best practices learned from EcoCAR2. We are in the third and last year of EcoCAR2, and we have already formed a core group of students in pursuit of EcoCAR”3”, for which the proposal is due in early December.

  15. Dynamics of completely unfolded and native proteins through solid-state nanopores as a function of electric driving force.

    PubMed

    Oukhaled, Abdelghani; Cressiot, Benjamin; Bacri, Laurent; Pastoriza-Gallego, Manuela; Betton, Jean-Michel; Bourhis, Eric; Jede, Ralf; Gierak, Jacques; Auvray, Loïc; Pelta, Juan

    2011-05-24

    We report experimentally the dynamic properties of the entry and transport of unfolded and native proteins through a solid-state nanopore as a function of applied voltage, and we discuss the experimental data obtained as compared to theory. We show an exponential increase in the event frequency of current blockades and an exponential decrease in transport times as a function of the electric driving force. The normalized current blockage ratio remains constant or decreases for folded or unfolded proteins, respectively, as a function of the transmembrane potential. The unfolded protein is stretched under the electric driving force. The dwell time of native compact proteins in the pore is almost 1 order of magnitude longer than that of unfolded proteins, and the event frequency for both protein conformations is low. We discuss the possible phenomena hindering the transport of proteins through the pores, which could explain these anomalous dynamics, in particular, electro-osmotic counterflow and protein adsorption on the nanopore wall.

  16. Battery Wear from Disparate Duty-Cycles: Opportunities for Electric-Drive Vehicle Battery Health Management; Preprint

    SciTech Connect

    Smith, K.; Earleywine, M.; Wood, E.; Pesaran, A.

    2012-10-01

    Electric-drive vehicles utilizing lithium-ion batteries experience wholly different degradation patterns than do conventional vehicles, depending on geographic ambient conditions and consumer driving and charging patterns. A semi-empirical life-predictive model for the lithium-ion graphite/nickel-cobalt-aluminum chemistry is presented that accounts for physically justified calendar and cycling fade mechanisms. An analysis of battery life for plug-in hybrid electric vehicles considers 782 duty-cycles from travel survey data superimposed with climate data from multiple geographic locations around the United States. Based on predicted wear distributions, opportunities for extending battery life including modification of battery operating limits, thermal and charge control are discussed.

  17. High-Voltage High-Energy Stretched Lens Array Square-Rigger (SLASR) for Direct-Drive Solar Electric Propulsion

    NASA Technical Reports Server (NTRS)

    Howell, Joe T.; O'Neill, Mark J.; Mankins, John C.

    2006-01-01

    Development is underway on a unique high-voltage, high energy solar concentrator array called Stretched Lens Array Square-Rigger (SLASR) for direct drive electric propulsion. The SLASR performance attributes closely match the critical needs of solar electric propulsion (SEP) systems, which may be used for space tugs to fuel efficiently transport cargo from low earth orbit (LEO) to low lunar orbit (LLO), in support of NASA's robotic and human exploration missions. Later SEP systems may similarly transport cargo from the earth-moon neighborhood to the Mars neighborhood. This paper will describe the SLASR technology, discuss SLASR developments and ground testing, and outline plans for future SLASR technology maturation.

  18. Angular Velocity's Neural Network Observer of the Electric Drive of TVR - IM Type Implemented in Software Environment LabVIEW

    NASA Astrophysics Data System (ADS)

    Kozlova, L.; Bolovin, E.; Payuk, L.

    2016-06-01

    One of the common ways to manage a smooth starting and stopping of asynchronous motors are soft-start system. For this provision is necessary to use a closed speed asynchronous electric drive of tiristor voltage regulator - induction motor (TVR-IM) type. Using real sensors significantly increases the cost of installation and also introduces a number of inconveniences in the operation of the actuator. Observer has clear advantages that are created on artificial neural network. Creating a neural network observer in program graphic programming LabVIEW will allow to evaluate the speed of rotation of the asynchronous electric.

  19. Transistors for Electric Motor Drives: High-Performance GaN HEMT Modules for Agile Power Electronics

    SciTech Connect

    2010-09-01

    ADEPT Project: Transphorm is developing transistors with gallium nitride (GaN) semiconductors that could be used to make cost-effective, high-performance power converters for a variety of applications, including electric motor drives which transmit power to a motor. A transistor acts like a switch, controlling the electrical energy that flows around an electrical circuit. Most transistors today use low-cost silicon semiconductors to conduct electrical energy, but silicon transistors don’t operate efficiently at high speeds and voltage levels. Transphorm is using GaN as a semiconductor material in its transistors because GaN performs better at higher voltages and frequencies, and it is more energy efficient than straight silicon. However, Transphorm is using inexpensive silicon as a base to help keep costs low. The company is also packaging its transistors with other electrical components that can operate quickly and efficiently at high power levels—increasing the overall efficiency of both the transistor and the entire motor drive.

  20. Dielectric spectroscopy studies and ac electrical conductivity on (AuZn)/TiO2/p-GaAs(110) MIS structures

    NASA Astrophysics Data System (ADS)

    Şafak Asar, Yasemin; Asar, Tarık; Altındal, Şemsettin; Özçelik, Süleyman

    2015-09-01

    In this study, we investigated temperature and voltage dependence of dielectric properties and ac electrical conductivity (σac) of (AuZn)/TiO2/p-GaAs(110) metal-insulator-semiconductor structures in the temperature range of 80-290 K using the capacitance-voltage ? and conductance-voltage ? measurements at 1 MHz. The intersection/crossing behaviour of C-V plots at sufficiently high forward biases and the increase in σac with increasing temperature was attributed to the lack of sufficient number of enough free charge carriers at low temperatures. The values of the dielectric constant (ε‧), dielectric loss (ε″), loss tangent ?, ac electrical conductivity (σac), the real and imaginary parts of electric modulus (?) were found to be strong functions of temperature and applied bias voltage. The Cole-Cole plots between ? have shown only one semicircle for each temperature. This indicates one of the relaxation processes was suppressed and this can be attributed to the surface polarization effect. On the other hand, ? plot has a peak for each temperature. The ? plots revealed two linear regions with different slopes for sufficiently high forward biases (0.0, 0.5, and 1.0 V) which correspond to low (80-200 K) and moderate/intermediate (230-290 K) temperatures. Thus, the values of activation energy (Ea) were obtained from the slope of these Arrhenius plots for two linear regions as 87.3 and 3.4 meV, respectively, at 1.0 V. On the other hand, Mott plots have only one linear region except for 260 and 290 K and Mott parameters were determined from these plots at 0.0, 0.5 and 1.0 V.

  1. The New NASA-STD-4005 and NASA-HDBK-4006, Essentials for Direct-Drive Solar Electric Propulsion

    NASA Technical Reports Server (NTRS)

    Ferguson, Dale C.

    2007-01-01

    High voltage solar arrays are necessary for direct-drive solar electric propulsion, which has many advantages, including simplicity and high efficiency. Even when direct-drive is not used, the use of high voltage solar arrays leads to power transmission and conversion efficiencies in electric propulsion Power Management and Distribution. Nevertheless, high voltage solar arrays may lead to temporary power disruptions, through the so-called primary electrostatic discharges, and may permanently damage arrays, through the so-called permanent sustained discharges between array strings. Design guidance is needed to prevent these solar array discharges, and to prevent high power drains through coupling between the electric propulsion devices and the high voltage solar arrays. While most electric propulsion systems may operate outside of Low Earth Orbit, the plasmas produced by their thrusters may interact with the high voltage solar arrays in many ways similarly to Low Earth Orbit plasmas. A brief description of previous experiences with high voltage electric propulsion systems will be given in this paper. There are two new official NASA documents available free through the NASA Standards website to help in designing and testing high voltage solar arrays for electric propulsion. They are NASA-STD-4005, the Low Earth Orbit Spacecraft Charging Design Standard, and NASA-HDBK-4006, the Low Earth Orbit Spacecraft Charging Design Handbook. Taken together, they can both educate the high voltage array designer in the engineering and science of spacecraft charging in the presence of dense plasmas and provide techniques for designing and testing high voltage solar arrays to prevent electrical discharges and power drains.

  2. Overview of the Safety Issues Associated with the Compressed Natural Gas Fuel System and Electric Drive System in a Heavy Hybrid Electric Vehicle

    SciTech Connect

    Nelson, S.C.

    2002-11-14

    This report evaluates the hazards that are unique to a compressed-natural-gas (CNG)-fueled heavy hybrid electric vehicle (HEV) design compared with a conventional heavy vehicle. The unique design features of the heavy HEV are the CNG fuel system for the internal-combustion engine (ICE) and the electric drive system. This report addresses safety issues with the CNG fuel system and the electric drive system. Vehicles on U. S. highways have been propelled by ICEs for several decades. Heavy-duty vehicles have typically been fueled by diesel fuel, and light-duty vehicles have been fueled by gasoline. The hazards and risks posed by ICE vehicles are well understood and have been generally accepted by the public. The economy, durability, and safety of ICE vehicles have established a standard for other types of vehicles. Heavy-duty (i.e., heavy) HEVs have recently been introduced to U. S. roadways, and the hazards posed by these heavy HEVs can be compared with the hazards posed by ICE vehicles. The benefits of heavy HEV technology are based on their potential for reduced fuel consumption and lower exhaust emissions, while the disadvantages are the higher acquisition cost and the expected higher maintenance costs (i.e., battery packs). The heavy HEV is more suited for an urban drive cycle with stop-and-go driving conditions than for steady expressway speeds. With increasing highway congestion and the resulting increased idle time, the fuel consumption advantage for heavy HEVs (compared with conventional heavy vehicles) is enhanced by the HEVs' ability to shut down. Any increase in fuel cost obviously improves the economics of a heavy HEV. The propulsion system for a heavy HEV is more complex than the propulsion system for a conventional heavy vehicle. The heavy HEV evaluated in this study has in effect two propulsion systems: an ICE fueled by CNG and an electric drive system with additional complexity and failure modes. This additional equipment will result in a less

  3. Hybrid-Electric Passenger Car Carbon Dioxide and Fuel Consumption Benefits Based on Real-World Driving.

    PubMed

    Holmén, Britt A; Sentoff, Karen M

    2015-08-18

    Hybrid-electric vehicles (HEVs) have lower fuel consumption and carbon dioxide (CO2) emissions than conventional vehicles (CVs), on average, based on laboratory tests, but there is a paucity of real-world, on-road HEV emissions and performance data needed to assess energy use and emissions associated with real-world driving, including the effects of road grade. This need is especially great as the electrification of the passenger vehicle fleet (from HEVs to PHEVs to BEVs) increases in response to climate and energy concerns. We compared tailpipe CO2 emissions and fuel consumption of an HEV passenger car to a CV of the same make and model during real-world, on-the-road network driving to quantify the in-use benefit of one popular full HEV technology. Using vehicle specific power (VSP) assignments that account for measured road grade, the mean CV/HEV ratios of CO2 tailpipe emissions or fuel consumption defined the corresponding HEV "benefit" factor for each VSP class (1 kW/ton resolution). Averaging over all VSP classes for driving in all seasons, including temperatures from -13 to +35 °C in relatively steep (-13.2 to +11.5% grade), hilly terrain, mean (±SD) CO2 emission benefit factors were 4.5 ± 3.6, 2.5 ± 1.7, and 1.4 ± 0.5 for city, exurban/suburban arterial and highway driving, respectively. Benefit factor magnitude corresponded to the frequency of electric-drive-only (EDO) operation, which was modeled as a logarithmic function of VSP. A combined model explained 95% of the variance in HEV benefit for city, 75% for arterial and 57% for highway driving. Benefit factors consistently exceeded 2 for VSP classes with greater than 50% EDO (i.e., only city and arterial driving). The reported HEV benefits account for real-world road grade that is often neglected in regulatory emissions and fuel economy tests. Fuel use HEV benefit factors were 1.3 and 2 for the regulatory highway (HWFET) and city (FTP) cycles, respectively, 18% and 31% higher than the EPA adjusted

  4. Hybrid-Electric Passenger Car Carbon Dioxide and Fuel Consumption Benefits Based on Real-World Driving.

    PubMed

    Holmén, Britt A; Sentoff, Karen M

    2015-08-18

    Hybrid-electric vehicles (HEVs) have lower fuel consumption and carbon dioxide (CO2) emissions than conventional vehicles (CVs), on average, based on laboratory tests, but there is a paucity of real-world, on-road HEV emissions and performance data needed to assess energy use and emissions associated with real-world driving, including the effects of road grade. This need is especially great as the electrification of the passenger vehicle fleet (from HEVs to PHEVs to BEVs) increases in response to climate and energy concerns. We compared tailpipe CO2 emissions and fuel consumption of an HEV passenger car to a CV of the same make and model during real-world, on-the-road network driving to quantify the in-use benefit of one popular full HEV technology. Using vehicle specific power (VSP) assignments that account for measured road grade, the mean CV/HEV ratios of CO2 tailpipe emissions or fuel consumption defined the corresponding HEV "benefit" factor for each VSP class (1 kW/ton resolution). Averaging over all VSP classes for driving in all seasons, including temperatures from -13 to +35 °C in relatively steep (-13.2 to +11.5% grade), hilly terrain, mean (±SD) CO2 emission benefit factors were 4.5 ± 3.6, 2.5 ± 1.7, and 1.4 ± 0.5 for city, exurban/suburban arterial and highway driving, respectively. Benefit factor magnitude corresponded to the frequency of electric-drive-only (EDO) operation, which was modeled as a logarithmic function of VSP. A combined model explained 95% of the variance in HEV benefit for city, 75% for arterial and 57% for highway driving. Benefit factors consistently exceeded 2 for VSP classes with greater than 50% EDO (i.e., only city and arterial driving). The reported HEV benefits account for real-world road grade that is often neglected in regulatory emissions and fuel economy tests. Fuel use HEV benefit factors were 1.3 and 2 for the regulatory highway (HWFET) and city (FTP) cycles, respectively, 18% and 31% higher than the EPA adjusted

  5. Changes of excitability in M1 induced by neuromuscular electrical stimulation differ between presence and absence of voluntary drive.

    PubMed

    Sugawara, Kenichi; Tanabe, Shigeo; Higashi, Toshio; Tsurumi, Takamasa; Kasai, Tatsuya

    2011-06-01

    The aim of this study is to investigate excitability changes in the human motor cortex induced by variable therapeutic electrical stimulations (TESs) with or without voluntary drive. We recorded motor-evoked potentials (MEPs) from extensor and flexor carpi radialis (FCR) muscles at rest and during FCR muscle contraction after the application of TES on FCR. TES application conditions were changed intensities, frequencies, and trains. In addition, to evaluate the contribution of M1 inhibitory circuits to the effects of TES application, we also recorded MEPs using paired-pulse transcranial magnetic stimulation. In resting muscle states, an increase in TES intensity resulted in an increase in MEP ratio in both the muscles. In contrast, when TES was applied to FCR during contraction, MEP ratios of both the muscles decreased with increased number of pulse trains. However, under both the states, MEP ratios decreased induced by paired-pulse transcranial magnetic stimulation in extensor carpi radialis to which TES was not applied. Excitability changes in M1 induced by TES application were reversibly modulated depending on the presence or absence of voluntary drive. This study showed that the therapy and the voluntary drive of the target muscles act together, and complement the effects of each other, which may be beneficial for optimizing the rehabilitation if the therapy accompanies voluntary drive. PMID:21088609

  6. Changes of excitability in M1 induced by neuromuscular electrical stimulation differ between presence and absence of voluntary drive.

    PubMed

    Sugawara, Kenichi; Tanabe, Shigeo; Higashi, Toshio; Tsurumi, Takamasa; Kasai, Tatsuya

    2011-06-01

    The aim of this study is to investigate excitability changes in the human motor cortex induced by variable therapeutic electrical stimulations (TESs) with or without voluntary drive. We recorded motor-evoked potentials (MEPs) from extensor and flexor carpi radialis (FCR) muscles at rest and during FCR muscle contraction after the application of TES on FCR. TES application conditions were changed intensities, frequencies, and trains. In addition, to evaluate the contribution of M1 inhibitory circuits to the effects of TES application, we also recorded MEPs using paired-pulse transcranial magnetic stimulation. In resting muscle states, an increase in TES intensity resulted in an increase in MEP ratio in both the muscles. In contrast, when TES was applied to FCR during contraction, MEP ratios of both the muscles decreased with increased number of pulse trains. However, under both the states, MEP ratios decreased induced by paired-pulse transcranial magnetic stimulation in extensor carpi radialis to which TES was not applied. Excitability changes in M1 induced by TES application were reversibly modulated depending on the presence or absence of voluntary drive. This study showed that the therapy and the voluntary drive of the target muscles act together, and complement the effects of each other, which may be beneficial for optimizing the rehabilitation if the therapy accompanies voluntary drive.

  7. Design and analysis of new fault-tolerant permanent magnet motors for four-wheel-driving electric vehicles

    NASA Astrophysics Data System (ADS)

    Liu, Guohai; Gong, Wensheng; Chen, Qian; Jian, Linni; Shen, Yue; Zhao, Wenxiang

    2012-04-01

    In this paper, a novel in-wheel permanent-magnet (PM) motor for four-wheel-driving electrical vehicles is proposed. It adopts an outer-rotor topology, which can help generate a large drive torque, in order to achieve prominent dynamic performance of the vehicle. Moreover, by adopting single-layer concentrated-windings, fault-tolerant teeth, and the optimal combination of slot and pole numbers, the proposed motor inherently offers negligible electromagnetic coupling between different phase windings, hence, it possesses a fault-tolerant characteristic. Meanwhile, the phase back electromotive force waveforms can be designed to be sinusoidal by employing PMs with a trapezoidal shape, eccentric armature teeth, and unequal tooth widths. The electromagnetic performance is comprehensively investigated and the optimal design is conducted by using the finite-element method.

  8. Plasmon and coupled plasmon-phonon modes in graphene in the presence of a driving electric field

    NASA Astrophysics Data System (ADS)

    Zhao, C. X.; Xu, W.; Dong, H. M.; Peeters, F. M.

    2014-05-01

    We present a theoretical study of the plasmon and coupled plasmon-phonon modes induced by intraband electron-electron interaction in graphene in the presence of driving dc electric field. We find that the electric field dependence of these collective excitation modes in graphene differs significantly from that in a conventional two-dimensional electron gas with a parabolic energy spectrum. This is due mainly to the fact that graphene has a linear energy spectrum and the Fermi velocity of electrons in graphene is much larger than the drift velocity of electrons. The obtained results demonstrate that the plasmon and coupled plasmon-phonon modes in graphene can be tuned by applying not only the gate voltage but also the source-to-drain field. The manipulation of plasmon and coupled plasmon-phonon modes by source-to-drain voltage can let graphene be more conveniently applied as an advanced plasmonic material.

  9. High-Voltage High-Energy Stretched Lens Array Square-Rigger (SLASR) for Direct-Drive Solar Electric Propulsion

    NASA Technical Reports Server (NTRS)

    Howell, Joe T.; O'Neill, Mark; Mankins, John C.

    2006-01-01

    Development is underway on a unique high-voltage, high-energy solar concentrator array called Stretched Lens Array Square-Rigger (SLASR) for direct drive electric propulsion. The SLASR performance attributes closely match the critical needs of solar electric propulsion (SEP) systems, which may be used for space tugs to fuel-efficiently transport cargo from low earth orbit (LEO) to low lunar orbit (LLO), in support of NASA s robotic and human exploration missions. Later SEP systems may similarly transport cargo from the earth-moon neighborhood to the Mars neighborhood. This paper will describe the SLASR technology, discuss SLASR developments and ground testing, and outline plans for future SLASR technology maturation.

  10. Electric Drive Dynamic Thermal System Model for Advanced Vehicle Propulsion Technologies: Cooperative Research and Development Final Report, CRADA Number CRD-09-360

    SciTech Connect

    Bennion, K.

    2013-10-01

    Electric drive systems, which include electric machines and power electronics, are a key enabling technology for advanced vehicle propulsion systems that reduce the dependence of the U.S. transportation sector on petroleum. However, to penetrate the market, these electric drive technologies must enable vehicle solutions that are economically viable. The push to make critical electric drivesystems smaller, lighter, and more cost-effective brings respective challenges associated with heat removal and system efficiency. In addition, the wide application of electric drive systems to alternative propulsion technologies ranging from integrated starter generators, to hybrid electric vehicles, to full electric vehicles presents challenges in terms of sizing critical components andthermal management systems over a range of in-use operating conditions. This effort focused on developing a modular modeling methodology to enable multi-scale and multi-physics simulation capabilities leading to generic electric drive system models applicable to alternative vehicle propulsion configurations. The primary benefit for the National Renewable Energy Laboratory (NREL) is the abilityto define operating losses with the respective impact on component sizing, temperature, and thermal management at the component, subsystem, and system level. However, the flexible nature of the model also allows other uses related to evaluating the impacts of alternative component designs or control schemes depending on the interests of other parties.

  11. Drive Control of an Electric Vehicle by a Non-linear Controller

    NASA Astrophysics Data System (ADS)

    Mubin, Marizan; Ouchi, Shigeto; Anabuki, Masatoshi; Hirata, Hiroshi

    The driving force of automobiles is transmitted by the frictional force between the tires and the road surface. This frictional force is a function of the weight of the car-body and the friction coefficient μ between the tires and the road surface. The friction coefficient μ is also a function of the following parameters: the slip ratio λ determined by the car-body speed and the wheel speed, and the condition of the road surface. Slippage of automobiles which causes much damage often occurs during accelerating and braking. In this paper, we propose a new drive control system which has an effect on acceleration and braking. In the drive control system, a non-linear controller designed by using a Lyapunov function is used. This non-linear controller has two functions: first one is μ control which moves the car-body, another one is λ control. The controller is designed in order that μ and λ work at noslip and with slip respectively. As another controller, a disturbance observer is used for estimating the car-body speed which is difficult to be measured. Then, this lead to the proof of the stability condition of the combined system which consists of two controllers: the non-linear controller and the disturbance observer. Finally, the effectiveness of this control system is proved by a very satisfactory simulation and experimental results for two cases.

  12. The analysis of diagnostics possibilities of the Dual- Drive electric power steering system using diagnostics scanner and computer method

    NASA Astrophysics Data System (ADS)

    Szczypiński-Sala, W.; Dobaj, K.

    2016-09-01

    The article presents the analysis of diagnostics possibilities of electric power steering system using computer diagnostics scanner. Several testing attempts were performed. There were analyzed the changes of torque moment exerted on steering wheel by the driver and the changes of the angle of rotation steering wheel accompanying them. The tests were conducted in variable conditions comprising wheel load and the friction coefficient of tyre road interaction. Obtained results enabled the analysis of the influence of changeable operations conditions, possible to acquire in diagnostics scanners of chosen parameters of electric power steering system. Moreover, simulation model of operation, electric drive power steering system with the use of the Matlab simulation software was created. The results of the measurements obtained in road conditions served to verify this model. Subsequently, model response to inputs change of the device was analyzed and its reaction to various constructional and exploitative parameters was checked. The entirety of conducted work constitutes a step to create a diagnostic monitor possible to use in self-diagnosis of electric power steering system.

  13. A 42-V Electrical and Hybrid Driving System Based on a Vehicular Waste-Heat Thermoelectric Generator

    NASA Astrophysics Data System (ADS)

    Deng, Y. D.; Fan, W.; Ling, K.; Su, C. Q.

    2012-06-01

    A 42-V powernet has been recognized as the next generation of vehicle electrical systems, and the waste-heat thermoelectric generator is becoming the future of vehicular energy conservation and emission reduction technologies. In this paper, effective utilization of vehicular waste-heat energy is proposed by introducing an electrical and hybrid driving system, which is an assemblage of a waste-heat thermoelectric generator, a 42-V powernet, and an integrated starter and generator (ISG). A vehicle model and the submodels for the new system have been built on the ADVISOR platform based on MATLAB/Simulink, and the dynamic performance of the vehicle model tested using the Economic Commission for Europe-Europe Urban Dynamometer Cycle driving cycle. The simulation results indicate that application of a 42-V waste-heat thermoelectric vehicle could be an integrated approach for fuel economy improvement and emission reduction, compared with a conventional internal combustion engine vehicle and an ISG-type 42-V vehicle.

  14. Near-term hybrid vehicle program, phase 1. Appendix B: Design trade-off studies. [various hybrid/electric power train configurations and electrical and mechanical drive-line components

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The relative attractiveness of various hybrid/electric power train configurations and electrical and mechanical drive-line components was studied. The initial screening was concerned primarily with total vehicle weight and economic factors and identified the hybrid power train combinations which warranted detailed evaluation over various driving cycles. This was done using a second-by-second vehicle simulation program which permitted the calculations of fuel economy, electricity usage, and emissions as a function of distance traveled in urban and highway driving. Power train arrangement possibilities were examined in terms of their effect on vehicle handling, safety, serviceability, and passenger comfort. A dc electric drive system utilizing a separately excited motor with field control and battery switching was selected for the near term hybrid vehicle. Hybrid vehicle simulations showed that for the first 30 mi (the electric range of the vehicle) in urban driving, the fuel economy was 80 mpg using a gasoline engine and 100 mpg using a diesel engine. In urban driving the hybrid would save about 75% of the fuel used by the conventional vehicle and in combined urban/highway driving the fuel saving is about 50%.

  15. A drive for all users

    SciTech Connect

    Drury, W.; Satya, T.

    1995-12-31

    The forces of industrial automation and efficiency, both in terms of process capability and energy, continue to fuel the rapid growth in the market for electrical variable speed drives. This demand coupled with the need for improved performance and the inevitable consequence of growth, results in a fiercely competitive market place. Within such an environment the claim of ``A drive for all users`` is not new, and those with some knowledge of the drives industry will consider any such claim with great skepticism. The literature on drives is littered with industrialists, and more than a few academics, claiming to have the ultimate drive, the optimum for each and every application. This situation is particularly true in the case of AC drive technology. The documented battles between proponents of current source verses PWM voltage source, not to mention the quest for the ultimate PWM strategy, have resulted in substantial deforestation of the planet. This paper makes no such unqualified claim rather it describes a very substantial and significant step towards such a eutopia.

  16. Electrical stress-induced instability of amorphous indium-gallium-zinc oxide thin-film transistors under bipolar ac stress

    SciTech Connect

    Lee, Sangwon; Jeon, Kichan; Park, Jun-Hyun; Kim, Sungchul; Kong, Dongsik; Kim, Dong Myong; Kim, Dae Hwan; Kim, Sangwook; Kim, Sunil; Hur, Jihyun; Park, Jae Chul; Song, Ihun; Kim, Chang Jung; Park, Youngsoo; Jung, U-In

    2009-09-28

    Bipolar ac stress-induced instability of amorphous indium-gallium-zinc oxide (a-IGZO) thin-film transistors is comparatively investigated with that under a positive dc gate bias stress. While the positive dc gate bias stress-induced threshold voltage shift ({delta}V{sub T}) is caused by the charge trapping into the interface/gate dielectric as reported in previous works, the dominant mechanism of the ac stress-induced {delta}V{sub T} is observed to be due to the increase in the acceptorlike deep states of the density of states (DOS) in the a-IGZO active layer. Furthermore, it is found that the variation of deep states in the DOS makes a parallel shift in the I{sub DS}-V{sub GS} curve with an insignificant change in the subthreshold slope, as well as the deformation of the C{sub G}-V{sub G} curves.

  17. Microfabricated AC impedance sensor

    DOEpatents

    Krulevitch, Peter; Ackler, Harold D.; Becker, Frederick; Boser, Bernhard E.; Eldredge, Adam B.; Fuller, Christopher K.; Gascoyne, Peter R. C.; Hamilton, Julie K.; Swierkowski, Stefan P.; Wang, Xiao-Bo

    2002-01-01

    A microfabricated instrument for detecting and identifying cells and other particles based on alternating current (AC) impedance measurements. The microfabricated AC impedance sensor includes two critical elements: 1) a microfluidic chip, preferably of glass substrates, having at least one microchannel therein and with electrodes patterned on both substrates, and 2) electrical circuits that connect to the electrodes on the microfluidic chip and detect signals associated with particles traveling down the microchannels. These circuits enable multiple AC impedance measurements of individual particles at high throughput rates with sufficient resolution to identify different particle and cell types as appropriate for environmental detection and clinical diagnostic applications.

  18. Analysis of Off-Board Powered Thermal Preconditioning in Electric Drive Vehicles: Preprint

    SciTech Connect

    Barnitt, R. A.; Brooker, A. D.; Ramroth, L.; Rugh , J.; Smith, K. A.

    2010-12-01

    Following a hot or cold thermal soak, vehicle climate control systems (air conditioning or heat) are required to quickly attain a cabin temperature comfortable to the vehicle occupants. In a plug-in hybrid electric or electric vehicle (PEV) equipped with electric climate control systems, the traction battery is the sole on-board power source. Depleting the battery for immediate climate control results in reduced charge-depleting (CD) range and additional battery wear. PEV cabin and battery thermal preconditioning using off-board power supplied by the grid or a building can mitigate the impacts of climate control. This analysis shows that climate control loads can reduce CD range up to 35%. However, cabin thermal preconditioning can increase CD range up to 19% when compared to no thermal preconditioning. In addition, this analysis shows that while battery capacity loss over time is driven by ambient temperature rather than climate control loads, concurrent battery thermal preconditioning can reduce capacity loss up to 7% by reducing pack temperature in a high ambient temperature scenario.

  19. Electromechanical properties of high coupling single crystals under large electric drive and uniaxial compression.

    PubMed

    Amin, Ahmed

    2005-10-01

    This work investigates the 33-mode electromechanical response of relaxor-ferroelectric lead magnesium niobate-lead titanate (PMN-PT) single crystals when driven with large fields approximately 0.4 MV/m under a combined direct current (DC) field and mechanical bias similar to those used in the design of sound projectors. It demonstrates that the remarkable small signal length extensional coupling (k33 > 0.90) and other electromechanical properties of morphotropic PMN-PT single crystals prevail under large drive. The observed k33 roll-off at 42 MPa compressive stress is analyzed in terms of the recent structural data and the high-order Devonshire theory of possible ferroelectric-ferroelectric transition trajectories.

  20. Torque linearizing hardware for the electric joint motors of a direct-drive robot

    SciTech Connect

    Muir, P.F.; Bryan, J.R.

    1991-12-31

    Many emerging high-performance robot control algorithms require the command of the joint torques; yet no known commercial robots provide such a capability. In this paper, we describe the design, development, testing and application of a VMEbus-based torque linearizing joint interface board (JIB). One JIB resides between the robot control processor and each joint motor amplifier. The JIB provides the control processor with the capability to read the motor position and apply accurate motor torques. The torque command capability derives from the application of a 128k {times} 8 EPROM lookup table for each motor phase. Because joint motor torque is dependent upon the torque command and the motor position, the hardware is designed to utilize the torque command and the current motor position as the address to retrieve the proper pulse-width for the PWM motor amplifier. The table look-up cycle operates independently of the robot controller at a 40KHz rate to provide constant joint torque as the motor rotates. We identify the proper table entries by an automated in situ data collection procedure. Static torque generation results show that the torque deviations are reduced from as much as 76% to below 5% for each of the three direct-drive motors (two are variable reluctance motors and one is brushless DC) on an AdeptTwo robot. These torque deviations are reduced below 2.5% if only the upper 90% of the torque range is considered. The torque deviations of the non-direct-drive joint are reduced by 50%. Dynamic robot edge following experiments show that the robot speed of operation can be more than doubled for a given applied force accuracy by utilizing the joint torque linearizing boards. 8 refs.

  1. Torque linearizing hardware for the electric joint motors of a direct-drive robot

    SciTech Connect

    Muir, P.F.; Bryan, J.R.

    1991-01-01

    Many emerging high-performance robot control algorithms require the command of the joint torques; yet no known commercial robots provide such a capability. In this paper, we describe the design, development, testing and application of a VMEbus-based torque linearizing joint interface board (JIB). One JIB resides between the robot control processor and each joint motor amplifier. The JIB provides the control processor with the capability to read the motor position and apply accurate motor torques. The torque command capability derives from the application of a 128k {times} 8 EPROM lookup table for each motor phase. Because joint motor torque is dependent upon the torque command and the motor position, the hardware is designed to utilize the torque command and the current motor position as the address to retrieve the proper pulse-width for the PWM motor amplifier. The table look-up cycle operates independently of the robot controller at a 40KHz rate to provide constant joint torque as the motor rotates. We identify the proper table entries by an automated in situ data collection procedure. Static torque generation results show that the torque deviations are reduced from as much as 76% to below 5% for each of the three direct-drive motors (two are variable reluctance motors and one is brushless DC) on an AdeptTwo robot. These torque deviations are reduced below 2.5% if only the upper 90% of the torque range is considered. The torque deviations of the non-direct-drive joint are reduced by 50%. Dynamic robot edge following experiments show that the robot speed of operation can be more than doubled for a given applied force accuracy by utilizing the joint torque linearizing boards. 8 refs.

  2. Torque linearizing hardware for the electric joint motors of a direct-drive robot

    NASA Astrophysics Data System (ADS)

    Muir, P. F.; Bryan, J. R.

    Many emerging high-performance robot control algorithms require the command of the joint torques, yet no known commercial robots provide such a capability. We describe the design, development, testing, and application of a VMEbus-based torque linearizing joint interface board (JIB). One JIB resides between the robot control processor and each joint motor amplifier. The JIB provides the control processor with the capability to read the motor position and apply accurate motor torques. The torque command capability derives from the application of a 128k x 8 EPROM lookup table for each motor phase. Because joint motor torque is dependent upon the torque command and the motor position, the hardware is designed to utilize the torque command and the current motor position as the address to retrieve the proper pulse-width for the PWM motor amplifier. The table look-up cycle operates independently of the robot controller at a 40KHz rate to provide constant joint torque as the motor rotates. We identify the proper table entries by an automated in situ data collection procedure. Static torque generation results show that the torque deviations are reduced from as much as 76 percent to below 5 percent for each of the three direct-drive motors (two are variable reluctance motors and one is brushless DC) on an AdeptTwo robot. These torque deviations are reduced below 2.5 percent if only the upper 90 percent of the torque range is considered. The torque deviations of the non-direct-drive joint are reduced by 50 percent. Dynamic robot edge following experiments show that the robot speed of operation can be more than doubled for a given applied force accuracy by utilizing the joint torque linearizing boards.

  3. Driving and braking control of PM synchronous motor based on low-resolution hall sensor for battery electric vehicle

    NASA Astrophysics Data System (ADS)

    Gu, Jing; Ouyang, Minggao; Li, Jianqiu; Lu, Dongbin; Fang, Chuan; Ma, Yan

    2013-01-01

    Resolvers are normally employed for rotor positioning in motors for electric vehicles, but resolvers are expensive and vulnerable to vibrations. Hall sensors have the advantages of low cost and high reliability, but the positioning accuracy is low. Motors with Hall sensors are typically controlled by six-step commutation algorithm, which brings high torque ripple. This paper studies the high-performance driving and braking control of the in-wheel permanent magnetic synchronous motor (PMSM) based on low-resolution Hall sensors. Field oriented control (FOC) based on Hall-effect sensors is developed to reduce the torque ripple. The positioning accuracy of the Hall sensors is improved by interpolation between two consecutive Hall signals using the estimated motor speed. The position error from the misalignment of the Hall sensors is compensated by the precise calibration of Hall transition timing. The braking control algorithms based on six-step commutation and FOC are studied. Two variants of the six-step commutation braking control, namely, half-bridge commutation and full-bridge commutation, are discussed and compared, which shows that the full-bridge commutation could better explore the potential of the back electro-motive forces (EMF), thus can deliver higher efficiency and smaller current ripple. The FOC braking is analyzed with the phasor diagrams. At a given motor speed, the motor turns from the regenerative braking mode into the plug braking mode if the braking torque exceeds a certain limit, which is proportional to the motor speed. Tests in the dynamometer show that a smooth control could be realized by FOC driving control and the highest efficiency and the smallest current ripple could be achieved by FOC braking control, compared to six-step commutation braking control. Therefore, FOC braking is selected as the braking control algorithm for electric vehicles. The proposed research ensures a good motor control performance while maintaining low cost and high

  4. Micro Climate Assessment of Grid-Connected Electric Drive Vehicles and Charging Infrastructure. Final Report

    SciTech Connect

    Schey, Stephen; Francfort, Jim

    2015-12-01

    Battelle Energy Alliance, LLC, managing and operating contractor for the U.S. Department of Energy’s Idaho National Laboratory, is the lead laboratory for the U.S. Department of Energy’s advanced vehicle testing. Battelle Energy Alliance, LLC contracted with Intertek Testing Services, North America to conduct several U.S. Department of Defense-based micro-climate studies to identify potential U.S. Department of Defense transportation systems that are strong candidates for introduction or expansion of plug-in electric vehicles (PEVs). The study included Joint Base Lewis McChord, located in Washington State; Naval Air Station Whidbey Island, located in Washington State; and United States Marine Corp Base Camp Lejeune, located in North Carolina. The project was divided into four tasks for each of the three bases studied. Task 1 consisted of surveying the non-tactical fleet of vehicles to begin review of vehicle mission assignments and types of vehicles in service. In Task 2, the daily operational characteristics of the vehicles were identified to select vehicles for further monitoring and attachment of data loggers. Task 3 recorded vehicle movements in order to characterize the vehicles’ missions. Results of the data analysis and observations were provided. Individual observations of these selected vehicles provided the basis for recommendations related to PEV adoption (i.e., whether a battery electric vehicle or plug-in hybrid electric vehicle [collectively referred to as PEVs] can fulfill the mission requirements). It also provided the basis for recommendations related to placement of PEV charging infrastructure. In Task 4, an implementation approach was provided for near-term adoption of PEVs into the respective fleets. Each facility was provided detailed reports on each of these tasks. This paper summarizes and provides observations on the project and completes Intertek’s required actions.

  5. Solar Arrays for Direct-Drive Electric Propulsion: Arcing at High Voltages

    NASA Technical Reports Server (NTRS)

    Schneider, Todd A.; Mikellides, I. G.; Jongeward, G. A.; Peterson, T.; Kerslake, T. W.; Snyder, D.; Ferguson, D.

    2004-01-01

    The results from an experimental investigation to assess arcing during operation of high voltage solar arrays in a plasma environment are presented. The experiments were part of an effort to develop systems that would allow safe operation of Hall-Effect Thrustefls) in direct-drive mode. Arc discharges are generated when the array is biased negative with respect to the plasma. If sustained for long periods of time between adjacent solar cells, arcs may severely damage a solar array, thus significantly shortening its lifetime. Most often sustained arcs are triggered by plasma produced during short-duration discharge arcs (approximately 20 microseconds). These trigger arcs are sparked between the semiconducting cell and the covering dielectric. Both trigger and sustained (greater than 1 millisecond) arcs have been captured during the tests. Current and voltage waveforms associated with the different arc events are presented. The test results have defined operational limits (thresholds) for the various array concepts studied that minimize the likelihood of damage from sustained arcs. Experimental trends regarding the effect of the solar array substrate on arc duration are also presented.

  6. Reliable, Efficient and Cost-Effective Electric Power Converter for Small Wind Turbines Based on AC-link Technology

    SciTech Connect

    Darren Hammell; Mark Holveck; DOE Project Officer - Keith Bennett

    2006-08-01

    Grid-tied inverter power electronics have been an Achilles heel of the small wind industry, providing opportunity for new technologies to provide lower costs, greater efficiency, and improved reliability. The small wind turbine market is also moving towards the 50-100kW size range. The unique AC-link power conversion technology provides efficiency, reliability, and power quality advantages over existing technologies, and Princeton Power will adapt prototype designs used for industrial asynchronous motor control to a 50kW small wind turbine design.

  7. Time-dependent changes in motor cortical excitability by electrical stimulation combined with voluntary drive.

    PubMed

    Sugawara, Kenichi; Yamaguchi, Tomofumi; Tanabe, Shigeo; Suzuki, Tomotaka; Saito, Kei; Higashi, Toshio

    2014-04-16

    Prolonged changes in primary motor cortex excitability in response to combined neuromuscular electrical stimulation (NMES) and voluntary contraction with motor evoked potentials (MEPs) were investigated by transcranial magnetic stimulation and recorded by mechanomyography. Participants included 22 healthy individuals. NMES was applied to the extensor carpi radialis (ECR) by voluntary ECR contraction with 20% maximum voluntary contraction (MVC) of wrist extension. MEPs were recorded from the flexor carpi radialis (FCR) and ECR at rest with NMES, at 20% MVC with NMES (combined), and at 20% MVC alone. Significant conditional effects were revealed in ECR and FCR. In the combined condition, MEPs showed gradual enhancement, and those in FCR were more inhibited than those in the control condition. Voluntary contraction with NMES increased primary motor cortex excitability in the agonist muscle, whereas the antagonist muscle might affect reciprocal modulation in the combined condition. PMID:24356108

  8. Radial electric field 3D modeling for wire arrays driving dynamic hohlraums on Z.

    SciTech Connect

    Mock, Raymond Cecil

    2007-06-01

    The anode-cathode structure of the Z-machine wire array results in a higher negative radial electric field (Er) on the wires near the cathode relative to the anode. The magnitude of this field has been shown to anti-correlate with the axial radiation top/bottom symmetry in the DH (Dynamic Hohlraum). Using 3D modeling, the structure of this field is revealed for different wire-array configurations and for progressive mechanical alterations, providing insight for minimizing the negative Er on the wire array in the anode-to-cathode region of the DH. Also, the 3D model is compared to Sasorov's approximation, which describes Er at the surface of the wire in terms of wire-array parameters.

  9. FPGA-based voltage and current dual drive system for high frame rate electrical impedance tomography.

    PubMed

    Khan, Shadab; Manwaring, Preston; Borsic, Andrea; Halter, Ryan

    2015-04-01

    Electrical impedance tomography (EIT) is used to image the electrical property distribution of a tissue under test. An EIT system comprises complex hardware and software modules, which are typically designed for a specific application. Upgrading these modules is a time-consuming process, and requires rigorous testing to ensure proper functioning of new modules with the existing ones. To this end, we developed a modular and reconfigurable data acquisition (DAQ) system using National Instruments' (NI) hardware and software modules, which offer inherent compatibility over generations of hardware and software revisions. The system can be configured to use up to 32-channels. This EIT system can be used to interchangeably apply current or voltage signal, and measure the tissue response in a semi-parallel fashion. A novel signal averaging algorithm, and 512-point fast Fourier transform (FFT) computation block was implemented on the FPGA. FFT output bins were classified as signal or noise. Signal bins constitute a tissue's response to a pure or mixed tone signal. Signal bins' data can be used for traditional applications, as well as synchronous frequency-difference imaging. Noise bins were used to compute noise power on the FPGA. Noise power represents a metric of signal quality, and can be used to ensure proper tissue-electrode contact. Allocation of these computationally expensive tasks to the FPGA reduced the required bandwidth between PC, and the FPGA for high frame rate EIT. In 16-channel configuration, with a signal-averaging factor of 8, the DAQ frame rate at 100 kHz exceeded 110 frames s (-1), and signal-to-noise ratio exceeded 90 dB across the spectrum. Reciprocity error was found to be for frequencies up to 1 MHz. Static imaging experiments were performed on a high-conductivity inclusion placed in a saline filled tank; the inclusion was clearly localized in the reconstructions obtained for both absolute current and voltage mode data. PMID:25376037

  10. FPGA-based voltage and current dual drive system for high frame rate electrical impedance tomography.

    PubMed

    Khan, Shadab; Manwaring, Preston; Borsic, Andrea; Halter, Ryan

    2015-04-01

    Electrical impedance tomography (EIT) is used to image the electrical property distribution of a tissue under test. An EIT system comprises complex hardware and software modules, which are typically designed for a specific application. Upgrading these modules is a time-consuming process, and requires rigorous testing to ensure proper functioning of new modules with the existing ones. To this end, we developed a modular and reconfigurable data acquisition (DAQ) system using National Instruments' (NI) hardware and software modules, which offer inherent compatibility over generations of hardware and software revisions. The system can be configured to use up to 32-channels. This EIT system can be used to interchangeably apply current or voltage signal, and measure the tissue response in a semi-parallel fashion. A novel signal averaging algorithm, and 512-point fast Fourier transform (FFT) computation block was implemented on the FPGA. FFT output bins were classified as signal or noise. Signal bins constitute a tissue's response to a pure or mixed tone signal. Signal bins' data can be used for traditional applications, as well as synchronous frequency-difference imaging. Noise bins were used to compute noise power on the FPGA. Noise power represents a metric of signal quality, and can be used to ensure proper tissue-electrode contact. Allocation of these computationally expensive tasks to the FPGA reduced the required bandwidth between PC, and the FPGA for high frame rate EIT. In 16-channel configuration, with a signal-averaging factor of 8, the DAQ frame rate at 100 kHz exceeded 110 frames s (-1), and signal-to-noise ratio exceeded 90 dB across the spectrum. Reciprocity error was found to be for frequencies up to 1 MHz. Static imaging experiments were performed on a high-conductivity inclusion placed in a saline filled tank; the inclusion was clearly localized in the reconstructions obtained for both absolute current and voltage mode data.

  11. Stability enhancement and fuel economy of the 4-wheel-drive hybrid electric vehicles by optimal tyre force distribution

    NASA Astrophysics Data System (ADS)

    Goodarzi, Avesta; Mohammadi, Masoud

    2014-04-01

    In this paper, vehicle stability control and fuel economy for a 4-wheel-drive hybrid vehicle are investigated. The integrated controller is designed within three layers. The first layer determines the total yaw moment and total lateral force made by using an optimal controller method to follow the desired dynamic behaviour of a vehicle. The second layer determines optimum tyre force distribution in order to optimise tyre usage and find out how the tyres should share longitudinal and lateral forces to achieve a target vehicle response under the assumption that all four wheels can be independently steered, driven, and braked. In the third layer, the active steering, wheel slip, and electrical motor torque controllers are designed. In the front axle, internal combustion engine (ICE) is coupled to an electric motor (EM). The control strategy has to determine the power distribution between ICE and EM to minimise fuel consumption and allowing the vehicle to be charge sustaining. Finally, simulations performed in MATLAB/SIMULINK environment show that the proposed structure could enhance the vehicle stability and fuel economy in different manoeuvres.

  12. Variability of particle number emissions from diesel and hybrid diesel-electric buses in real driving conditions.

    PubMed

    Sonntag, Darrell B; Gao, H Oliver; Holmén, Britt A

    2008-08-01

    A linear mixed model was developed to quantify the variability of particle number emissions from transit buses tested in real-world driving conditions. Two conventional diesel buses and two hybrid diesel-electric buses were tested throughout 2004 under different aftertreatments, fuels, drivers, and bus routes. The mixed model controlled the confounding influence of factors inherent to on-board testing. Statistical tests showed that particle number emissions varied significantly according to the after treatment, bus route, driver, bus type, and daily temperature, with only minor variability attributable to differences between fuel types. The daily setup and operation of the sampling equipment (electrical low pressure impactor) and mini-dilution system contributed to 30-84% of the total random variability of particle measurements among tests with diesel oxidation catalysts. By controlling for the sampling day variability, the model better defined the differences in particle emissions among bus routes. In contrast, the low particle number emissions measured with diesel particle filters (decreased by over 99%) did not vary according to operating conditions or bus type but did vary substantially with ambient temperature.

  13. Experimental Verification of Electric Drive Technologies Based on Artificial Intelligence Tools

    NASA Technical Reports Server (NTRS)

    Rubaai, Ahmed; Kankam, David (Technical Monitor)

    2003-01-01

    A laboratory implementation of a fuzzy logic-tracking controller using a low cost Motorola MC68HC11E9 microprocessor is described in this report. The objective is to design the most optimal yet practical controller that can be implemented and marketed, and which gives respectable performance, even when the system loads, inertia and parameters are varying. A distinguishing feature of this work is the by-product goal of developing a marketable, simple, functional and low cost controller. Additionally, real-time nonlinearities are not ignored, and a mathematical model is not required. A number of components have been designed, built and tested individually, and in various combinations of hardware and software segments. These components have been integrated with a brushless motor to constitute the drive system. A microprocessor-based FLC is incorporated to provide robust speed and position control. Design objectives that are difficult to express mathematically can be easily incorporated in a fuzzy logic-based controller by linguistic information (in the form of fuzzy IF-THEN rules). The theory and design are tested in the laboratory using a hardware setup. Several test cases have been conducted to confirm the effectiveness of the proposed controller. The results indicate excellent tracking performance for both speed and position trajectories. For the purpose of comparison, a bang-bang controller has been tested. The fuzzy logic controller performs significantly better than the traditional bang-bang controller. The bang-bang controller has been shown to be relatively inaccurate and lacking in robustness. Description of the implementation hardware system is also given.

  14. Dielectric properties and study of AC electrical conduction mechanisms by non-overlapping small polaron tunneling model in Bis(4-acetylanilinium) tetrachlorocuprate(II) compound

    NASA Astrophysics Data System (ADS)

    Abkari, A.; Chaabane, I.; Guidara, K.

    2016-09-01

    In the present work, the synthesis and characterization of the Bis(4-acetylanilinium) tetrachlorocuprate(II) compound are presented. The structure of this compound is analyzed by X-ray diffraction which confirms the formation of single phase and is in good agreement the literature. Indeed, the Thermo gravimetric Analysis (TGA) shows that the decomposition of the compound is observed in the range of 420-520 K. However, the differential thermal analysis (DTA) indicates the presence of a phase transition at T=363 k. Furthermore, the dielectric properties and AC conductivity were studied over a temperature range (338-413 K) and frequency range (200 Hz-5 MHz) using complex impedance spectroscopy. Dielectric measurements confirmed such thermal analyses by exhibiting the presence of an anomaly in the temperature range of 358-373 K. The complex impedance plots are analyzed by an electrical equivalent circuit consisting of resistance, constant phase element (CPE) and capacitance. The activation energy values of two distinct regions are obtained from log σT vs 1000/T plot and are found to be E=1.27 eV (T<363 K) and E=1.09 eV (363 Kac conductivity, σac, has been analyzed by Jonscher's universal power law σ(ω)=σdc+Aωs. The value of s is to be temperature-dependent, which has a tendency to increase with temperature and the non-overlapping small polaron tunneling (NSPT) model is the most applicable conduction mechanism in the title compound. Complex impedance spectra of [C8H10NO]2CuCl4 at different temperatures.

  15. Driving rural energy access: a second-life application for electric-vehicle batteries

    NASA Astrophysics Data System (ADS)

    Ambrose, Hanjiro; Gershenson, Dimitry; Gershenson, Alexander; Kammen, Daniel

    2014-09-01

    Building rural energy infrastructure in developing countries remains a significant financial, policy and technological challenge. The growth of the electric vehicle (EV) industry will rapidly expand the resource of partially degraded, ‘retired’, but still usable batteries in 2016 and beyond. These batteries can become the storage hubs for community-scale grids in the developing world. We model the resource and performance potential and the technological and economic aspects of the utilization of retired EV batteries in rural and decentralized mini- and micro-grids. We develop and explore four economic scenarios across three battery chemistries to examine the impacts on transport and recycling logistics. We find that EVs sold through 2020 will produce 120-549 GWh in retired storage potential by 2028. Outlining two use scenarios for decentralized systems, we discuss the possible impacts on global electrification rates. We find that used EV batteries can provide a cost-effective and lower environmental impact alternative to existing lead-acid storage systems in these applications.

  16. A Soft-Switching Inverter for High-Temperature Advanced Hybrid Electric Vehicle Traction Motor Drives

    SciTech Connect

    Lai, Jason; Yu, Wensong; Sun, Pengwei; Leslie, Scott; Prusia, Duane; Arnet, Beat; Smith, Chris; Cogan, Art

    2012-03-31

    The state-of-the-art hybrid electric vehicles (HEVs) require the inverter cooling system to have a separate loop to avoid power semiconductor junction over temperatures because the engine coolant temperature of 105°C does not allow for much temperature rise in silicon devices. The proposed work is to develop an advanced soft-switching inverter that will eliminate the device switching loss and cut down the power loss so that the inverter can operate at high-temperature conditions while operating at high switching frequencies with small current ripple in low inductance based permanent magnet motors. The proposed tasks also include high-temperature packaging and thermal modeling and simulation to ensure the packaged module can operate at the desired temperature. The developed module will be integrated with the motor and vehicle controller for dynamometer and in-vehicle testing to prove its superiority. This report will describe the detailed technical design of the soft-switching inverters and their test results. The experiments were conducted both in module level for the module conduction and switching characteristics and in inverter level for its efficiency under inductive and dynamometer load conditions. The performance will be compared with the DOE original specification.

  17. Efficacy of low level electric current (A-C) for controlling quagga mussles in the Welland Canal

    SciTech Connect

    Fears, C.; Mackie, G.L.

    1995-06-01

    The efficacy of systems (for which patents are pending) which use low-voltage A-C currents for preventing settlement and attachment by zebra mussels were tested with steel rods and plates placed near the intake of a pulp and paper plant in the Welland Canal at Thorold, Ontario. Six racks made of 16 ft. (4.9 m), 2x4s (5.1 x 10.2 cm) were placed into the Welland Canal on August 5, 1994. One rack had 1/8th in (3.2 mm) diam x 12 in (30.5 cm) long steel rods, each separated by 2 in (5.1 cm) attached to pressure treated wood and concrete blocks and an A-C current of 16 v (or 8 v/in); rack 2 had steel rods of the same configuration but 12 v (or 6 v/in) was applied; rack 3 was identical to these but no current was applied and was used as a rod control. The remaining three racks had steel plates, each plate being 3 in (7.6 cm) wide X 24 in (61 cm) long X 1/4 in (6.4 mm) thick and separated by 2 in (5.1 cm); one had 12 v applied (or 6 v/in), another had 16 v applied (or 8 v/in), and the third had no current and was used as a plate control. The racks were placed on the upstream and downstream side of the intake at a depth of about 7 ft (2.1 m) where the mussels populations were heaviest (as determined by SCUBA diving). All mussels were quagga mussels (Dreissena bugensis). The racks were pulled in mid November after settlement was complete and the results showed: (1) complete prevention of settlement of both new recruits and translocators at 8 volts/in with steel rods on both wood and concrete surfaces and with steel plate trash bars; (2) partial prevention of settlement at 6 volts/in with steel rods on both wood and concrete surfaces and steel plates; and (3) that, at current kilowatt hr rates, total efficacy at 8 volts/in would cost approximately $10.80/day/1000 sq ft using rods to protect concrete walls and about $16.32/day/1000 sq ft to protect 3 in wide x 1/4 in thick trash bars. These costs can be reduced even further with pulse dosed AC currents.

  18. Observer-based higher order sliding mode control of power factor in three-phase AC/DC converter for hybrid electric vehicle applications

    NASA Astrophysics Data System (ADS)

    Liu, Jianxing; Laghrouche, Salah; Wack, Maxime

    2014-06-01

    In this paper, a full-bridge boost power converter topology is studied for power factor control, using output higher order sliding mode control. The AC/DC converters are used for charging the battery and super-capacitor in hybrid electric vehicles from the utility. The proposed control forces the input currents to track the desired values, which can control the output voltage while keeping the power factor close to one. Super-twisting sliding mode observer is employed to estimate the input currents and load resistance only from the measurement of output voltage. Lyapunov analysis shows the asymptotic convergence of the closed-loop system to zero. Multi-rate simulation illustrates the effectiveness and robustness of the proposed controller in the presence of measurement noise.

  19. PM Motor Parametric Design Analyses for a Hybrid Electric Vehicle Traction Drive Application

    SciTech Connect

    Staunton, R.H.

    2004-10-11

    The Department of Energy's (DOE) Office of FreedomCAR (Cooperative Automotive Research) and Vehicle Technologies office has a strong interest in making rapid progress in permanent magnet (PM) machine development. The DOE FreedomCAR program is directing various technology development projects that will advance the technology and hopefully lead to a near-term request for proposals (RFP) for a to-be-determined level of initial production. This aggressive approach is possible because the technology is clearly within reach and the approach is deemed essential, based on strong market demand, escalating fuel prices, and competitive considerations. In response, this study began parallel development paths that included a literature search/review, development and utilization of multiple parametric models, verification of the modeling methodology, development of an interior PM (IPM) machine baseline design, development of alternative machine baseline designs, and cost analyses for several candidate machines. This report summarizes the results of these activities as of September 2004. This report provides background and summary information for recent machine parametric studies and testing programs that demonstrate both the potential capabilities and technical limitations of brushless PM machines (axial gap and radial gap), the IPM machine, the surface-mount PM machines (interior or exterior rotor), induction machines, and switched-reluctance machines. The FreedomCAR program, while acknowledging the progress made by Oak Ridge National Laboratory (ORNL), Delphi, Delco-Remy International, and others in these programs, has redirected efforts toward a ''short path'' to a marketable and competitive PM motor for hybrid electric vehicle (HEV) traction applications. The program has developed a set of performance targets for the type of traction machine desired. The short-path approach entails a comprehensive design effort focusing on the IPM machine and meeting the performance targets

  20. Driving mechanisms of ionic polymer actuators having electric double layer capacitor structures.

    PubMed

    Imaizumi, Satoru; Kato, Yuichi; Kokubo, Hisashi; Watanabe, Masayoshi

    2012-04-26

    Two solid polymer electrolytes, composed of a polyether-segmented polyurethaneurea (PEUU) and either a lithium salt (lithium bis(trifluoromethanesulfonyl)amide: Li[NTf2]) or a nonvolatile ionic liquid (1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)amide: [C2mim][NTf2]), were prepared in order to utilize them as ionic polymer actuators. These salts were preferentially dissolved in the polyether phases. The ionic transport mechanism of the polyethers was discussed in terms of the diffusion coefficients and ionic transference numbers of the incorporated ions, which were estimated by means of pulsed-field gradient spin-echo (PGSE) NMR. There was a distinct difference in the ionic transport properties of each polymer electrolyte owing to the difference in the magnitude of interactions between the cations and the polyether. The anionic diffusion coefficient was much faster than that of the cation in the polyether/Li[NTf2] electrolyte, whereas the cation diffused faster than the anion in the polyether/[C2mim][NTf2] electrolyte. Ionic polymer actuators, which have a solid-state electric-double-layer-capacitor (EDLC) structure, were prepared using these polymer electrolyte membranes and ubiquitous carbon materials such as activated carbon and acetylene black. On the basis of the difference in the motional direction of each actuator against applied voltages, a simple model of the actuation mechanisms was proposed by taking the difference in ionic transport properties into consideration. This model discriminated the behavior of the actuators in terms of the products of transference numbers and ionic volumes. The experimentally observed behavior of the actuators was successfully explained by this model. PMID:22489566

  1. PM Motor Parametric Design Analyses for Hybrid Electric Vehicle Traction Drive Application: Interim Report

    SciTech Connect

    Staunton, R.H.

    2004-08-11

    The Department of Energy's (DOE) Office of FreedomCAR (Cooperative Automotive Research) and Vehicle Technologies has a strong interest in making rapid progress in permanent magnet (PM) machine development. The program is directing various technology development projects that will advance the technology and lead to request for proposals (RFP) for manufacturer prototypes. This aggressive approach is possible because the technology is clearly within reach and the approach is deemed essential, based on strong market demand, escalating fuel prices, and competitive considerations. In response, this study began parallel development paths that included a literature search/review, development and utilization of multiple parametric models to determine the effects of design parameters, verification of the modeling methodology, development of an interior PM (IPM) machine baseline design, development of alternative machine baseline designs, and cost analyses for several candidate machines. This interim progress report summarizes the results of these activities as of June 2004. This report provides background and summary information for recent machine parametric studies and testing programs that demonstrate both the potential capabilities and technical limitations of brushless PM machines (axial gap and radial gap), the IPM machine, the surface-mount PM machines (interior or exterior rotor), induction machines, and switched reluctance machines. The FreedomCAR program, while acknowledging the progress made by Oak Ridge National Laboratory, Delphi, Delco-Remy International, and others in these programs, has redirected efforts toward a ''short path'' to a marketable and competitive PM motor for hybrid electric vehicle traction applications. The program has developed a set of performance targets for the type of traction machine desired. The short-path approach entails a comprehensive design effort focusing on the IPM machine and meeting the performance targets. The selection of the

  2. Modeling the performance and cost of lithium-ion batteries for electric-drive vehicles.

    SciTech Connect

    Nelson, P. A. Gallagher, K. G. Bloom, I. Dees, D. W.

    2011-10-20

    This report details the Battery Performance and Cost model (BatPaC) developed at Argonne National Laboratory for lithium-ion battery packs used in automotive transportation. The model designs the battery for a specified power, energy, and type of vehicle battery. The cost of the designed battery is then calculated by accounting for every step in the lithium-ion battery manufacturing process. The assumed annual production level directly affects each process step. The total cost to the original equipment manufacturer calculated by the model includes the materials, manufacturing, and warranty costs for a battery produced in the year 2020 (in 2010 US$). At the time this report is written, this calculation is the only publically available model that performs a bottom-up lithium-ion battery design and cost calculation. Both the model and the report have been publically peer-reviewed by battery experts assembled by the U.S. Environmental Protection Agency. This report and accompanying model include changes made in response to the comments received during the peer-review. The purpose of the report is to document the equations and assumptions from which the model has been created. A user of the model will be able to recreate the calculations and perhaps more importantly, understand the driving forces for the results. Instructions for use and an illustration of model results are also presented. Almost every variable in the calculation may be changed by the user to represent a system different from the default values pre-entered into the program. The distinct advantage of using a bottom-up cost and design model is that the entire power-to-energy space may be traversed to examine the correlation between performance and cost. The BatPaC model accounts for the physical limitations of the electrochemical processes within the battery. Thus, unrealistic designs are penalized in energy density and cost, unlike cost models based on linear extrapolations. Additionally, the

  3. Transport of particles and microorganisms in microfluidic channels using rectified ac electro-osmotic flow

    PubMed Central

    Wu, Wen-I; Selvaganapathy, P. Ravi; Ching, Chan Y.

    2011-01-01

    A new method is demonstrated to transport particles, cells, and other microorganisms using rectified ac electro-osmotic flows in open microchannels. The rectified flow is obtained by synchronous zeta potential modulation with the driving potential in the microchannel. Experiments were conducted to transport both neutral, charged particles, and microorganisms of various sizes. A maximum speed of 50 μm∕s was obtained for 8 μm polystyrene beads, without any electrolysis, using a symmetrical square waveform driving electric field of 5 V∕mm at 10 Hz and a 360 V gate potential with its polarity synchronized with the driving potential (phase lag=0°). PMID:21522497

  4. Research recommendations for ac interfacing between electric utility transmission and distribution systems and wind, photovoltaics, and OTEC energy systems

    NASA Astrophysics Data System (ADS)

    Longrigg, P.; Buell, E. H.

    1985-03-01

    Work that deals semiquantitatively with many integration problems that may have to be solved as wind, photovoltaic, and ocean energy systems are tied into electrical transmission utility grids is documented. The problems that will arise as these distributed storage and generation (DSG) energy systems are integrated into the electric utility grids are not yet fully known, and their extent may depend on the level of penetration of the DSGs into the grid network. Aspects of DSG integration covered are fuse and relay coordination, harmonics, communications, control protocols, safety, and artificial intelligence (computer driven controls). An appendix on the effects of electromagnetic pulse is also included.

  5. ELECTRICAL AND ELECTRONIC INDUSTRIAL CONTROL. A-C CONVENTIONAL MAGNETIC MOTOR CONTROL, PART II, UNIT 6, ASSIGNMENTS.

    ERIC Educational Resources Information Center

    SUTTON, MACK C.

    THIS STUDY GUIDE IS FOR INDIVIDUAL STUDENT USE IN STUDYING ALTERNATING CURRENT CONVENTIONAL MAGNETIC MOTOR CONTROL IN ELECTRICAL-ELECTRONIC PROGRAMS. IT WAS DEVELOPED BY AN INSTRUCTIONAL MATERIALS SPECIALIST AND ADVISERS. EACH OF THE 10 ASSIGNMENT SHEETS PROVIDES THE LESSON SUBJECT, PURPOSE, INTRODUCTORY INFORMATION, STUDY REFERENCES,…

  6. ELECTRICAL AND ELECTRONIC INDUSTRIAL CONTROL. A-C CONVENTIONAL MAGNETIC MOTOR CONTROL, PART II, UNIT 6, INSTRUCTOR'S GUIDE.

    ERIC Educational Resources Information Center

    SUTTON, MACK C.

    THIS GUIDE IS FOR TEACHER USE IN DIRECTING INDIVIDUAL STUDY OF ALTERNATING CURRENT CONVENTIONAL MAGNETIC MOTOR CONTROL IN ELECTRICAL-ELECTRONIC PROGRAMS. IT WAS DEVELOPED BY AN INSTRUCTIONAL MATERIALS SPECIALIST AND ADVISERS. EACH OF THE 10 INSTRUCTOR'S SHEETS GIVES THE LESSON SUBJECT, PURPOSE, INTRODUCTORY INFORMATION, REFERENCES, SUPPLEMENTARY…

  7. ELECTRICAL AND ELECTRONIC INDUSTRIAL CONTROL. A-C CONVENTIONAL MAGNETIC MOTOR CONTROL, PART I, UNIT 5, INSTRUCTOR'S GUIDE.

    ERIC Educational Resources Information Center

    SUTTON, MACK C.

    THIS GUIDE IS FOR TEACHER USE IN DIRECTING INDIVIDUAL STUDY OF ALTERNATING CURRENT CONVENTIONAL MAGNETIC MOTOR CONTROL IN ELECTRICAL-ELECTRONIC PROGRAMS. IT WAS DEVELOPED BY AN INSTRUCTIONAL MATERIALS SPECIALIST AND ADVISERS. EACH OF THE 10 INSTRUCTOR'S SHEETS GIVES THE LESSON SUBJECT, PURPOSE, INTRODUCTORY INFORMATION, REFERENCES, AND…

  8. ELECTRICAL AND ELECTRONIC INDUSTRIAL CONTROL. A-C CONVENTIONAL MAGNETIC MOTOR CONTROL, PART I, UNIT 5, ASSIGNMENTS.

    ERIC Educational Resources Information Center

    SUTTON, MACK C.

    THIS GUIDE IS FOR INDIVIDUAL STUDENT USE IN STUDYING ALTERNATING CURRENT CONVENTIONAL MAGNETIC MOTOR CONTROL IN ELECTRICAL-ELECTRONIC PROGRAMS. IT WAS DEVELOPED BY AN INSTRUCTIONAL MATERIALS SPECIALIST AND ADVISERS. EACH OF THE 10 ASSIGNMENT SHEETS PROVIDES THE LESSON SUBJECT, PURPOSE, INTRODUCTORY INFORMATION, STUDY REFERENCES, SUPPLEMENTARY…

  9. Dynamic characteristics of double-barrier nanostructures with asymmetric barriers of finite height and widths in a strong ac electric field

    SciTech Connect

    Chuenkov, V. A.

    2013-12-15

    The theory of the interaction of a monoenergetic flow of injected electrons with a strong high-frequency ac electric field in resonant-tunneling diode (RTD) structures with asymmetric barriers of finite height and width is generalized. In the quasi-classical approximation, electron wavefunctions and tunneling functions in the quantum well and barriers are found. Analytical expressions for polarization currents in RTDs are derived in both the general case and in a number of limiting cases. It is shown that the polarization currents and radiation power in RTDs with asymmetric barriers strongly depend on the ratio of the probabilities of electron tunneling through the emitter and collector barriers. In the quantum mode, when δ = ε − ε{sub r} = ħω ≪ Γ (ε is the energy of electrons injected in the RTD, ħ is Planck’s constant, ω is the ac field frequency, ε{sub r} and Γ are the energy and width of the resonance level, respectively), the active polarization current in a field of E ≈ 2.8ħω/ea (e is the electron charge and a is the quantum-well width) reaches a maximum equal in magnitude to 84% of the direct resonant current, if the probability of electron tunneling through the emitter barrier is much higher than that through the collector barrier. The radiation-generation power at frequencies of ω = 10{sup 12}–10{sup 13} s{sup −1} can reach 10{sup 5}–10{sup 6} W/cm{sup 2} in this case.

  10. AC Loss Calculation of REBCO Cables by the Combination of Electric Circuit Model and 2D Finite Element Method

    NASA Astrophysics Data System (ADS)

    Noji, H.

    This study investigates the losses in a two conducting-layer REBCO cable fabricated by researchers at Furukawa Electric Co. Ltd. The losses were calculated using a combination of my electric circuit (EC) model with a two-dimensional finite element method (2D FEM). The helical pitches of the tapes in each layer, P1 and P2, were adjusted to equalize the current in both cable layers, although the loss calculation assumed infinite helical pitches and the same current in each layer at first. The results showed that the losses depended on the relative tape-position angle between the layers (θ/θ'), because the vertical field between adjacent tapes in the same layer varied with θ/θ'. When simulating the real cable, the helical pitches were adjusted and the layer currents were calculated by the EC model. These currents were input to the 2D FEM to compute the losses. The losses changed along the cable length because the difference between P1 and P2 altered the θ/θ' along this direction. The average angle-dependent and position-dependent losses were equal and closely approximated the measured losses. As an example to reduce the loss in this cable, the angle and the helical pitches were fixed at θ/θ' = 0.5 and P1 = P2 = 100 mm (S-direction). The calculation with these conditions indicated that the loss is about one order of magnitude lower than the measurement.

  11. Experimental and theoretical study of AC electrical conduction mechanisms of Organic-inorganic hybrid compound Bis (4-acetylanilinium) tetrachlorocadmiate (II)

    NASA Astrophysics Data System (ADS)

    Jellibi, A.; Chaabane, I.; Guidara, K.

    2016-06-01

    A new organic-inorganic bis (4-acetylaniline) tetrachlorocadmate [C8H10NO]2[CdCl4] can be obtained by slow evaporation at room temperature and characterized by X-ray powder diffraction. It crystallized in an orthorhombic system (Cmca space group). The material electrical properties were characterized by impedance spectroscopy technique in the frequency range from 209 Hz-5 MHz and temperature 413 to 460 K. Besides, the impedance plots show semicircle arcs at different temperatures and an electrical equivalent circuit has been proposed to interpret the impedance results. The circuits consist of the parallel combination of a resistance (R), capacitance (C) and fractal capacitance (CPE). The variation of the exponent s as a function of temperature suggested that the conduction mechanism in Bis (4-acetylanilinium) tetrachlorocadmiate compound is governed by two processes which can be ascribed to a hopping transport mechanism: correlated barrier hopping (CBH) model below 443 K and the small polaron tunneling (SPT) model above 443 K.

  12. An automatically-shifted two-speed transaxle system for an electric vehicle

    NASA Technical Reports Server (NTRS)

    Gordon, H. S.; Hassman, G. V.

    1980-01-01

    An automatic shifting scheme for a two speed transaxle for use with an electric vehicle propulsion system is described. The transaxle system was to be installed in an instrumented laboratory propulsion system of an ac electric vehicle drive train. The transaxle which had been fabricated is also described.

  13. Uncertainty evaluation in the measurement of power frequency electric and magnetic fields from AC overhead power lines.

    PubMed

    Ztoupis, I N; Gonos, I F; Stathopulos, I A

    2013-11-01

    Measurements of power frequency electric and magnetic fields from alternating current power lines are carried out in order to evaluate the exposure levels of the human body on the general public. For any electromagnetic field measurement, it is necessary to define the sources of measurement uncertainty and determine the total measurement uncertainty. This paper is concerned with the problems of measurement uncertainty estimation, as the measurement uncertainty budget calculation techniques recommended in standardising documents and research studies are barely described. In this work the total uncertainty of power frequency field measurements near power lines in various measurement sites is assessed by considering not only all available equipment data, but also contributions that depend on the measurement procedures, environmental conditions and characteristics of the field source, which are considered to increase the error of measurement. A detailed application example for power frequency field measurements is presented here by accredited laboratory.

  14. The effect of electric field geometry on the performance of electromembrane extraction systems: footprints of a third driving force along with migration and diffusion.

    PubMed

    Moazami, Hamid Reza; Hosseiny Davarani, Saied Saeed; Mohammadi, Jamil; Nojavan, Saeed; Abrari, Masoud

    2015-09-01

    The distribution of electric field vectors was first calculated for electromembrane extraction (EME) systems in classical and cylindrical electrode geometries. The results showed that supported liquid membrane (SLM) has a general field amplifying effect due to its lower dielectric constant in comparison with aqueous donor/acceptor solutions. The calculated norms of the electric field vector showed that a DC voltage of 50 V can create huge electric field strengths up to 64 kV m(-1) and 111 kV m(-1) in classical and cylindrical geometries respectively. In both cases, the electric field strength reached its peak value on the inner wall of the SLM. In the case of classical geometry, the field strength was a function of the polar position of the SLM whereas the field strength in cylindrical geometry was angularly uniform. In order to investigate the effect of the electrode geometry on the performance of real EME systems, the analysis was carried out in three different geometries including classical, helical and cylindrical arrangements using naproxen and sodium diclofenac as the model analytes. Despite higher field strength and extended cross sectional area, the helical and cylindrical geometries gave lower recoveries with respect to the classical EME. The observed decline of the signal was proved to be against the relations governing migration and diffusion processes, which means that a third driving force is involved in EME. The third driving force is the interaction between the radially inhomogeneous electric field and the analyte in its neutral form.

  15. Simulation of an ac electro-osmotic pump with step microelectrodes

    NASA Astrophysics Data System (ADS)

    Kim, Byoung Jae; Lee, Seung-Hyun; Rezazadeh, Soghra; Sung, Hyung Jin

    2011-05-01

    Pumps with step microelectrodes subjected to an ac voltage are known to have faster pumping rates than those with planar asymmetric microelectrodes. The driving force for pumping in these systems is ac electro-osmosis. This paper aims to understand the flow behaviors of pumps with step microelectrodes by using a realistic model applicable to high external voltages. This model takes the steric effect due to the finite sizes of ions into account and copes with the exponential sensitivity of the counterion concentration to voltage. The effects on the pumping flow rate of varying the pump parameters were investigated. The geometrical parameters were optimized, and the effects of varying the ac frequency and amplitude were examined. The electrical potential of the fluid and the electrical charge at the electrode surface were solved simultaneously, and the Stokes equation was used to describe the fluid flow.

  16. Engineering model of the electric drives of separation device for simulation of automatic control systems of reactive power compensation by means of serially connected capacitors

    NASA Astrophysics Data System (ADS)

    Juromskiy, V. M.

    2016-09-01

    It is developed a mathematical model for an electric drive of high-speed separation device in terms of the modeling dynamic systems Simulink, MATLAB. The model is focused on the study of the automatic control systems of the power factor (Cosφ) of an actuator by compensating the reactive component of the total power by switching a capacitor bank in series with the actuator. The model is based on the methodology of the structural modeling of dynamic processes.

  17. Characterization of the near-term electric vehicle (ETV-1) breadboard propulsion system over the SAE J227a driving schedule D

    NASA Technical Reports Server (NTRS)

    Sargent, N. B.; Dustin, M. O.

    1981-01-01

    The electric test vehicle one (ETV-1) was built from the ground up with present state of the art technology. Two vehicles were built and are presently being evaluated by NASA's Jet Propulsion Laboratory (JPL). A duplicate set of propulsion system components was built, mounted on a breadboard, and delivered to NASA's Lewis Research Center for testing on the road load simulator (RLS). Driving cycle tests completed on the system are described.

  18. ac current generation in chiral magnetic insulators and Skyrmion motion induced by the spin Seebeck effect.

    PubMed

    Lin, Shi-Zeng; Batista, Cristian D; Reichhardt, Charles; Saxena, Avadh

    2014-05-01

    We show that a temperature gradient induces an ac electric current in multiferroic insulators when the sample is embedded in a circuit. We also show that a thermal gradient can be used to move magnetic Skyrmions in insulating chiral magnets: the induced magnon flow from the hot to the cold region drives the Skyrmions in the opposite direction via a magnonic spin transfer torque. Both results are combined to compute the effect of Skyrmion motion on the ac current generation and demonstrate that Skyrmions in insulators are a promising route for spin caloritronics applications.

  19. ac current generation in chiral magnetic insulators and Skyrmion motion induced by the spin Seebeck effect.

    PubMed

    Lin, Shi-Zeng; Batista, Cristian D; Reichhardt, Charles; Saxena, Avadh

    2014-05-01

    We show that a temperature gradient induces an ac electric current in multiferroic insulators when the sample is embedded in a circuit. We also show that a thermal gradient can be used to move magnetic Skyrmions in insulating chiral magnets: the induced magnon flow from the hot to the cold region drives the Skyrmions in the opposite direction via a magnonic spin transfer torque. Both results are combined to compute the effect of Skyrmion motion on the ac current generation and demonstrate that Skyrmions in insulators are a promising route for spin caloritronics applications. PMID:24856718

  20. Influence of temperature on the electric, dielectric and AC conductivity properties of nano-crystalline zinc substituted cobalt ferrite synthesized by solution combustion technique

    NASA Astrophysics Data System (ADS)

    Rani, Ritu; Kumar, Gagan; Batoo, Khalid M.; Singh, M.

    2014-06-01

    Cobalt-zinc nanoferrites with formulae Co ZnFeO, where x = 0.0, 0.1, 0.2 and 0.3, have been synthesized by solution combustion technique. The variation of DC resistivity with temperature shows the semiconducting behavior of all nanoferrites. The dielectric properties such as dielectric constant (') and dielectric loss tangent (tan are investigated as a function of temperature and frequency. Dielectric constant and loss tangent are found to be increasing with an increase in temperature while with an increase in frequency both, ' and tan , are found to be decreasing. The dielectric properties have been explained on the basis of space charge polarization according to Maxwell-Wagner's two-layer model and the hopping of charge between Fe and Fe. Further, a very high value of dielectric constant and a low value of tan are the prime achievements of the present work. The AC electrical conductivity ( is studied as a function of temperature as well as frequency and is observed to be increasing with the increase in temperature and frequency.

  1. Vehicle dynamics control of four in-wheel motor drive electric vehicle using gain scheduling based on tyre cornering stiffness estimation

    NASA Astrophysics Data System (ADS)

    Xiong, Lu; Yu, Zhuoping; Wang, Yang; Yang, Chen; Meng, Yufeng

    2012-06-01

    This paper focuses on the vehicle dynamic control system for a four in-wheel motor drive electric vehicle, aiming at improving vehicle stability under critical driving conditions. The vehicle dynamics controller is composed of three modules, i.e. motion following control, control allocation and vehicle state estimation. Considering the strong nonlinearity of the tyres under critical driving conditions, the yaw motion of the vehicle is regulated by gain scheduling control based on the linear quadratic regulator theory. The feed-forward and feedback gains of the controller are updated in real-time by online estimation of the tyre cornering stiffness, so as to ensure the control robustness against environmental disturbances as well as parameter uncertainty. The control allocation module allocates the calculated generalised force requirements to each in-wheel motor based on quadratic programming theory while taking the tyre longitudinal/lateral force coupling characteristic into consideration. Simulations under a variety of driving conditions are carried out to verify the control algorithm. Simulation results indicate that the proposed vehicle stability controller can effectively stabilise the vehicle motion under critical driving conditions.

  2. Subcontract Report: Final Report on Assessment of Motor Technologies for Traction Drives of Hybrid and Electric Vehicles (Subcontract #4000080341)

    SciTech Connect

    Fezzler, Raymond

    2011-03-01

    Currently, interior permanent magnet (IPM) motors with rare-earth (RE) magnets are almost universally used for hybrid and electric vehicles (EVs) because of their superior properties, particularly power density. However, there is now a distinct possibility of limited supply or very high cost of RE magnets that could make IPM motors unavailable or too expensive. Because development of electric motors is a critical part of the U.S. Department of Energy (DOE) Advanced Power Electronics and Motors activity, DOE needs to determine which options should be investigated and what barriers should be addressed. Therefore, in order to provide a basis for deciding which research topics should be pursued, an assessment of various motor technologies was conducted to determine which, if any, is potentially capable of meeting FreedomCAR 2015 and 2020 targets. Highest priority was given to IPM, surface mounted permanent magnet (SPM), induction, and switched reluctance (SR) motors. Also of interest, but with lesser emphasis, were wheel motors, multiple-rotor motors, motors with external excitation, and several others that emerged from the assessment. Cost and power density (from a design perspective, the power density criterion translates to torque density) are emerging as the two most important properties of motors for traction drives in hybrid and EVs, although efficiency and specific power also are very important. The primary approach for this assessment involved interviews with original equipment manufacturers (OEMs), their suppliers, and other technical experts. For each technology, the following issues were discussed: (1) The current state-of-the-art performance and cost; (2) Recent trends in the technology; (3) Inherent characteristics of the motor - which ones limit the ability of the technology to meet the targets and which ones aid in meeting the target; (4) What research and development (R&D) would be needed to meet the targets; and (5) The potential for the technology to

  3. 27. INTERIOR VIEW LOOKING SOUTHWEST IN THE ELECTRICAL MOTOR ROOM. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    27. INTERIOR VIEW LOOKING SOUTHWEST IN THE ELECTRICAL MOTOR ROOM. FROM LEFT TO RIGHT. DC GENERATOR, AC MOTOR, OLD DC GENERATOR, OPENING FOR THE BELT TO THE CLUTCH ASSEMBLY FOR THE MILL POWER SYSTEM. THE BOARDS THAT ARE ASKEW WERE PROTECTION AROUND THE DRIVE BELT. THE SMALL MOTOR IN THE FOREGROUND IS THE MOTOR THAT MOST RECENTLY POWERED THE MILL'S BELT DRIVE SYSTEM. - Standard Gold Mill, East of Bodie Creek, Northeast of Bodie, Bodie, Mono County, CA

  4. AC photovoltaic module magnetic fields

    SciTech Connect

    Jennings, C.; Chang, G.J.; Reyes, A.B.; Whitaker, C.M.

    1997-12-31

    Implementation of alternating current (AC) photovoltaic (PV) modules, particularly for distributed applications such as PV rooftops and facades, may be slowed by public concern about electric and magnetic fields (EMF). This paper documents magnetic field measurements on an AC PV module, complementing EMF research on direct-current PV modules conducted by PG and E in 1993. Although not comprehensive, the PV EMF data indicate that 60 Hz magnetic fields (the EMF type of greatest public concern) from PV modules are comparable to, or significantly less than, those from household appliances. Given the present EMF research knowledge, AC PV module EMF may not merit considerable concern.

  5. Effect of regional grid mix, driving patterns and climate on the comparative carbon footprint of gasoline and plug-in electric vehicles in the United States

    NASA Astrophysics Data System (ADS)

    Yuksel, Tugce; Tamayao, Mili-Ann M.; Hendrickson, Chris; Azevedo, Inês M. L.; Michalek, Jeremy J.

    2016-04-01

    We compare life cycle greenhouse gas (GHG) emissions from several light-duty passenger gasoline and plug-in electric vehicles (PEVs) across US counties by accounting for regional differences due to marginal grid mix, ambient temperature, patterns of vehicle miles traveled (VMT), and driving conditions (city versus highway). We find that PEVs can have larger or smaller carbon footprints than gasoline vehicles, depending on these regional factors and the specific vehicle models being compared. The Nissan Leaf battery electric vehicle has a smaller carbon footprint than the most efficient gasoline vehicle (the Toyota Prius) in the urban counties of California, Texas and Florida, whereas the Prius has a smaller carbon footprint in the Midwest and the South. The Leaf is lower emitting than the Mazda 3 conventional gasoline vehicle in most urban counties, but the Mazda 3 is lower emitting in rural Midwest counties. The Chevrolet Volt plug-in hybrid electric vehicle has a larger carbon footprint than the Prius throughout the continental US, though the Volt has a smaller carbon footprint than the Mazda 3 in many urban counties. Regional grid mix, temperature, driving conditions, and vehicle model all have substantial implications for identifying which technology has the lowest carbon footprint, whereas regional patterns of VMT have a much smaller effect. Given the variation in relative GHG implications, it is unlikely that blunt policy instruments that favor specific technology categories can ensure emission reductions universally.

  6. Simultaneous distribution of AC and DC power

    DOEpatents

    Polese, Luigi Gentile

    2015-09-15

    A system and method for the transport and distribution of both AC (alternating current) power and DC (direct current) power over wiring infrastructure normally used for distributing AC power only, for example, residential and/or commercial buildings' electrical wires is disclosed and taught. The system and method permits the combining of AC and DC power sources and the simultaneous distribution of the resulting power over the same wiring. At the utilization site a complementary device permits the separation of the DC power from the AC power and their reconstruction, for use in conventional AC-only and DC-only devices.

  7. Strategic responses to CO2 emission reduction targets drive shift in U.S. electric sector water use

    EPA Science Inventory

    The reliance of the U.S. electric sector on water makes this sector vulnerable to climate change and variability. We use the EPAUS9r MARKAL model to investigate changes in U.S. electric sector water withdrawal and consumption through 2055 under alternative energy system-wide CO2...

  8. Electromechanical systems with transient high power response operating from a resonant AC link

    NASA Technical Reports Server (NTRS)

    Burrows, Linda M.; Hansen, Irving G.

    1992-01-01

    The combination of an inherently robust asynchronous (induction) electrical machine with the rapid control of energy provided by a high frequency resonant AC link enables the efficient management of higher power levels with greater versatility. This could have a variety of applications from launch vehicles to all-electric automobiles. These types of systems utilize a machine which is operated by independent control of both the voltage and frequency. This is made possible by using an indirect field-oriented control method which allows instantaneous torque control in all four operating quadrants. Incorporating the AC link allows the converter in these systems to switch at the zero crossing of every half cycle of the AC waveform. This zero loss switching of the link allows rapid energy variations to be achieved without the usual frequency proportional switching loss. Several field-oriented control systems were developed by LeRC and General Dynamics Space Systems Division under contract to NASA. A description of a single motor, electromechanical actuation system is presented. Then, focus is on a conceptual design for an AC electric vehicle. This design incorporates an induction motor/generator together with a flywheel for peak energy storage. System operation and implications along with the associated circuitry are addressed. Such a system would greatly improve all-electric vehicle ranges over the Federal Urban Driving Cycle (FUD).

  9. Use of an AC electric field in galvanotactic on/off switching of the motion of a microstructure blotted by Serratia marcescens

    NASA Astrophysics Data System (ADS)

    Tran, Trung-Hieu; Hyung Kim, Dal; Kim, Jihoon; Jun Kim, Min; Byun, Doyoung

    2011-08-01

    In this study, we manipulated the swimming direction of bacteria and controlled the switching off movement by using dc and ac galvanotaxis. The microstructures blotted by Serratia marcescens could be spontaneously manipulated and switched off at the desired position. The optimum ac frequency for switching off the microstructural motion was 7 Hz. We built a mathematical model to analyze and understand the oscillating motion of microstructure.

  10. Electrically powered hand tool

    DOEpatents

    Myers, Kurt S.; Reed, Teddy R.

    2007-01-16

    An electrically powered hand tool is described and which includes a three phase electrical motor having a plurality of poles; an electrical motor drive electrically coupled with the three phase electrical motor; and a source of electrical power which is converted to greater than about 208 volts three-phase and which is electrically coupled with the electrical motor drive.

  11. 21 CFR 886.1630 - AC-powered photostimulator.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...) Identification. An AC-powered photostimulator is an AC-powered device intended to provide light stimulus which allows measurement of retinal or visual function by perceptual or electrical methods (e.g.,...

  12. Integrated Testing, Simulation and Analysis of Electric Drive Options for Medium-Duty Parcel Delivery Vehicles: Preprint

    SciTech Connect

    Ramroth, L. A.; Gonder, J.; Brooker, A.

    2012-09-01

    The National Renewable Energy Laboratory verified diesel-conventional and diesel-hybrid parcel delivery vehicle models to evaluate petroleum reduction and cost implications of plug-in hybrid gasoline and diesel variants. These variants are run on a field-data-derived design matrix to analyze the effects of drive cycle, distance, battery replacements, battery capacity, and motor power on fuel consumption and lifetime cost. Two cost scenarios using fuel prices corresponding to forecasted highs for 2011 and 2030 and battery costs per kilowatt-hour representing current and long-term targets compare plug-in hybrid lifetime costs with diesel conventional lifetime costs. Under a future cost scenario of $100/kWh battery energy and $5/gal fuel, plug-in hybrids are cost effective. Assuming a current cost of $700/kWh and $3/gal fuel, they rarely recoup the additional motor and battery cost. The results highlight the importance of understanding the application's drive cycle, daily driving distance, and kinetic intensity. For instances in the current-cost scenario where the additional plug-in hybrid cost is regained in fuel savings, the combination of kinetic intensity and daily distance travelled does not coincide with the usage patterns observed in the field data. If the usage patterns were adjusted, the hybrids could become cost effective.

  13. Operation Method for AC Motor Control during Power Interruption in Direct AC/AC Converter System

    NASA Astrophysics Data System (ADS)

    Shizu, Keiichiro; Azuma, Satoshi

    Direct AC/AC converters have been studied due to their potential use in power converters with no DC-link capacitor, which can contribute to the miniaturization of power converters. However, the absence of a DC-link capacitor makes it difficult to control the AC motor during power interruption. First, this paper proposes a system that realizes AC motor control during power interruption by utilizing a clamp capacitor. In general, direct AC/AC converters have a clamp circuit consisting of a rectifier diode(s) and a clamp capacitor in order to avoid over-voltages. In the proposed system, there is an additional semiconductor switch reverse-parallel to the rectifier diode(s), and the clamp capacitor voltage can be utilized for AC motor control by turning on the additional switch. Second, this paper discusses an operation method for AC motor control and clamp capacitor voltage control during power interruption. In the proposed method “DC-link voltage control”, the kinetic energy in the AC motor is transformed into electrical energy and stored in the clamp capacitor; the clamp capacitor is therefore charged and the capacitor voltage is controlled to remain constant at an instruction value. Third, this paper discusses a switching operation during power interruption. A dead-time is introduced between the operation of turning off all switches on the rectifier side and the operation of turning on the additional switch, which prevents the occurrence of a short circuit between the interrupted power source and the clamp capacitor. Finally, experimental results are presented. During power interruptions, an output current was continuously obtained and the clamp capacitor voltage was maintained to be equal to the instruction value of the capacitor voltage. These results indicate that both AC motor control and capacitor voltage control were successfully achieved by using the proposed system.

  14. Lectures on magnetohydrodynamical drives

    NASA Astrophysics Data System (ADS)

    Loigom, Villem

    The paper deals with nonconventional types of electrical machines and drives - magnetohydrodynamical (MHD) machines and drives. In cardinal it is based on the research conducted with participation of the author in Tallinn Technical University at the Institute of Electrical Drives and Power Electronics, where the use of magnetohydrodynamical motors and drives in the metallurgical and casting industries have been studied for a long time. Major research interests include the qualities and applications of the induction MHD-drives for set in the motion (pumping, turning, dosing, mixing, etc.) non-ferrous molten metals like Al, Mg, Sn, Pb, Na, K, and their alloys. The first part of the paper describes induction MHD motors and their electrohydraulical qualities. In the second part energy conversion problems are described. Also, on the basis of the analogy between electromechanical and electrohydraulical phenomenas, static and dynamic qualities of MHD drives with induction MHD machines are discussed.

  15. AC Electrokinetics of Physiological Fluids for Biomedical Applications.

    PubMed

    Lu, Yi; Liu, Tingting; Lamanda, Ariana C; Sin, Mandy L Y; Gau, Vincent; Liao, Joseph C; Wong, Pak Kin

    2015-12-01

    Alternating current (AC) electrokinetics is a collection of processes for manipulating bulk fluid mass and embedded objects with AC electric fields. The ability of AC electrokinetics to implement the major microfluidic operations, such as pumping, mixing, concentration, and separation, makes it possible to develop integrated systems for clinical diagnostics in nontraditional health care settings. The high conductivity of physiological fluids presents new challenges and opportunities for AC electrokinetics-based diagnostic systems. In this review, AC electrokinetic phenomena in conductive physiological fluids are described followed by a review of the basic microfluidic operations and the recent biomedical applications of AC electrokinetics. The future prospects of AC electrokinetics for clinical diagnostics are presented.

  16. Dual excitation multiphase electrostatic drive

    SciTech Connect

    Niino, Toshiki; Higuchi, Toshiro |; Egawa, Saku

    1995-12-31

    A novel electrostatic drive technology named Dual Excitation Multiphase Electrostatic Drive (DEMED) was presented. A basic DEMED consisted of two plastic films in which 3-phase parallel electrodes were embedded and was driven by a 3-phase ac excitation to the electrodes. Static characteristics of DEMED were calculated and tested and the results agreed very well. Three prototype motors of DEMED were fabricated using commercially available technique. The first prototype consisted of a single slider and stator and generated a linear motion with a slider`s motion range of about 5mm. It weighed 7g and generated a power of 1.6W and a thrust force of 4.4N. The second prototype consisted of 50 layer stack of linear motors, summing their outputs. It weighed 3.6kg and generated a propulsive force of 310N being powered with boosted commercial 3-phase electricity. The third prototype consisted of a rotor and a stator in which electrodes were arranged radially and generated rotational motion. The maximum power of 36mW was generated by the prototype weighing only 260mg for its rotor and stator. From the results of the numerical calculation, a practical design methodology for the motor was determined. An optimal design for a motor employing currently available material and fabrication techniques is provided as an example. Analyses predict that force generation over the interfacial area between the slider and stator of this motor would be 3,900N/m{sup 2}.

  17. Evaluation of a Smartphone Platform as a Wireless Interface Between Tongue Drive System and Electric-Powered Wheelchairs

    PubMed Central

    Kim, Jeonghee; Huo, Xueliang; Minocha, Julia; Holbrook, Jaimee; Laumann, Anne; Ghovanloo, Maysam

    2013-01-01

    Tongue drive system (TDS) is a new wireless assistive technology (AT) for the mobility impaired population. It provides users with the ability to drive powered wheelchairs (PWC) and access computers using their unconstrained tongue motion. Migration of the TDS processing unit and user interface platform from a bulky personal computer to a smartphone (iPhone) has significantly facilitated its usage by turning it into a true wireless and wearable AT. After implementation of the necessary interfacing hardware and software to allow the smartphone to act as a bridge between the TDS and PWC, the wheelchair navigation performance and associated learning was evaluated in nine able-bodied subjects in five sessions over a 5-week period. Subjects wore magnetic tongue studs over the duration of the study and drove the PWC in an obstacle course with their tongue using three different navigation strategies; namely unlatched, latched, and semiproportional. Qualitative aspects of using the TDS–iPhone–PWC interface were also evaluated via a five-point Likert scale questionnaire. Subjects showed more than 20% improvement in the overall completion time between the first and second sessions, and maintained a modest improvement of ~9% per session over the following three sessions. PMID:22531737

  18. Evaluation of a smartphone platform as a wireless interface between tongue drive system and electric-powered wheelchairs.

    PubMed

    Kim, Jeonghee; Huo, Xueliang; Minocha, Julia; Holbrook, Jaimee; Laumann, Anne; Ghovanloo, Maysam

    2012-06-01

    Tongue drive system (TDS) is a new wireless assistive technology (AT) for the mobility impaired population. It provides users with the ability to drive powered wheelchairs (PWC) and access computers using their unconstrained tongue motion. Migration of the TDS processing unit and user interface platform from a bulky personal computer to a smartphone (iPhone) has significantly facilitated its usage by turning it into a true wireless and wearable AT. After implementation of the necessary interfacing hardware and software to allow the smartphone to act as a bridge between the TDS and PWC, the wheelchair navigation performance and associated learning was evaluated in nine able-bodied subjects in five sessions over a 5-week period. Subjects wore magnetic tongue studs over the duration of the study and drove the PWC in an obstacle course with their tongue using three different navigation strategies; namely unlatched, latched, and semiproportional. Qualitative aspects of using the TDS-iPhone-PWC interface were also evaluated via a five-point Likert scale questionnaire. Subjects showed more than 20% improvement in the overall completion time between the first and second sessions, and maintained a modest improvement of ∼9% per session over the following three sessions. PMID:22531737

  19. Electricity Demand of PHEVs Operated by Private Households and Commercial Fleets: Effects of Driving and Charging Behavior

    SciTech Connect

    John Smart; Matthew Shirk; Ken Kurani; Casey Quinn; Jamie Davies

    2010-11-01

    Automotive and energy researchers have made considerable efforts to predict the impact of plug-in hybrid vehicle (PHEV) charging on the electrical grid. This work has been done primarily through computer modeling and simulation. The US Department of Energy’s (DOE) Advanced Vehicle Testing Activity (AVTA), in partnership with the University of California at Davis’s Institute for Transportation Stuides, have been collecting data from a diverse fleet of PHEVs. The AVTA is conducted by the Idaho National Laboratory for DOE’s Vehicle Technologies Program. This work provides the opportunity to quantify the petroleum displacement potential of early PHEV models, and also observe, rather than simulate, the charging behavior of vehicle users. This paper presents actual charging behavior and the resulting electricity demand from these PHEVs operating in undirected, real-world conditions. Charging patterns are examined for both commercial-use and personal-use vehicles. Underlying reasons for charging behavior in both groups are also presented.

  20. All-organic electrostrictive polymer composites with low driving electrical voltages for micro-fluidic pump applications.

    PubMed

    Le, Minh Quyen; Capsal, Jean-Fabien; Galineau, Jérémy; Ganet, Florent; Yin, Xunqian; Yang, Mingchia Dawn; Chateaux, Jean-François; Renaud, Louis; Malhaire, Christophe; Cottinet, Pierre-Jean; Liang, Richard

    2015-07-03

    This paper focuses on the improvement of a relaxor ferroelectric terpolymer, i.e., poly (vinylidene fluoride-trifluoroethylene-chlorofluoroethylene) [P(VDF-TrFE-CFE)], filled with a bis(2-ethylhexyl) phthalate (DEHP). The developed material gave rise to a significantly increased longitudinal electrostrictive strain, as well as an increased mechanical energy density under a relatively low electric field. These features were attributed to the considerably enhanced dielectric permittivity and a decreased Young modulus as a result of the introduction of only small DEHP plasticizer molecules. In addition, the plasticizer-filled terpolymer only exhibited a slight decrease of the dielectric breakdown strength, which was a great advantage with respect to the traditional polymer-based electrostrictive composites. More importantly, the approach proposed herein is promising for the future development and scale-up of new high-performance electrostrictive dielectrics under low applied electrical fields through modification simply by blending with a low-cost plasticizer. An experimental demonstration based on a flexible micro-fluidic application is described at the end of this paper, confirming the attractive characteristics of the proposed materials as well as the feasibility of integrating them as micro-actuators in small-scale devices.

  1. All-organic electrostrictive polymer composites with low driving electrical voltages for micro-fluidic pump applications

    NASA Astrophysics Data System (ADS)

    Le, Minh Quyen; Capsal, Jean-Fabien; Galineau, Jérémy; Ganet, Florent; Yin, Xunqian; Yang, Mingchia (Dawn); Chateaux, Jean-François; Renaud, Louis; Malhaire, Christophe; Cottinet, Pierre-Jean; Liang, Richard

    2015-07-01

    This paper focuses on the improvement of a relaxor ferroelectric terpolymer, i.e., poly (vinylidene fluoride-trifluoroethylene-chlorofluoroethylene) [P(VDF-TrFE-CFE)], filled with a bis(2-ethylhexyl) phthalate (DEHP). The developed material gave rise to a significantly increased longitudinal electrostrictive strain, as well as an increased mechanical energy density under a relatively low electric field. These features were attributed to the considerably enhanced dielectric permittivity and a decreased Young modulus as a result of the introduction of only small DEHP plasticizer molecules. In addition, the plasticizer-filled terpolymer only exhibited a slight decrease of the dielectric breakdown strength, which was a great advantage with respect to the traditional polymer-based electrostrictive composites. More importantly, the approach proposed herein is promising for the future development and scale-up of new high-performance electrostrictive dielectrics under low applied electrical fields through modification simply by blending with a low-cost plasticizer. An experimental demonstration based on a flexible micro-fluidic application is described at the end of this paper, confirming the attractive characteristics of the proposed materials as well as the feasibility of integrating them as micro-actuators in small-scale devices.

  2. CONTROL ROD DRIVE

    DOEpatents

    Chapellier, R.A.; Rogers, I.

    1961-06-27

    Accurate and controlled drive for the control rod is from an electric motor. A hydraulic arrangement is provided to balance a piston against which a control rod is urged by the application of fluid pressure. The electric motor drive of the control rod for normal operation is made through the aforementioned piston. In the event scramming is required, the fluid pressure urging the control rod against the piston is relieved and an opposite fluid pressure is applied. The lack of mechanical connection between the electric motor and control rod facilitates the scramming operation.

  3. 21 CFR 880.5500 - AC-powered patient lift.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false AC-powered patient lift. 880.5500 Section 880.5500... Devices § 880.5500 AC-powered patient lift. (a) Identification. An AC-powered lift is an electrically powered device either fixed or mobile, used to lift and transport patients in the horizontal or...

  4. 21 CFR 880.5500 - AC-powered patient lift.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false AC-powered patient lift. 880.5500 Section 880.5500... Devices § 880.5500 AC-powered patient lift. (a) Identification. An AC-powered lift is an electrically powered device either fixed or mobile, used to lift and transport patients in the horizontal or...

  5. 21 CFR 880.5500 - AC-powered patient lift.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false AC-powered patient lift. 880.5500 Section 880.5500... Devices § 880.5500 AC-powered patient lift. (a) Identification. An AC-powered lift is an electrically powered device either fixed or mobile, used to lift and transport patients in the horizontal or...

  6. 21 CFR 880.5500 - AC-powered patient lift.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false AC-powered patient lift. 880.5500 Section 880.5500... Devices § 880.5500 AC-powered patient lift. (a) Identification. An AC-powered lift is an electrically powered device either fixed or mobile, used to lift and transport patients in the horizontal or...

  7. Magnitude and value of electric vehicle emissions reductions for six driving cycles in four US cities with varying air quality problems

    SciTech Connect

    Wang, Q.; Santini, D.L.

    1992-12-31

    The emissions of logically competing mid-1990 gasoline vehicles (GVs) and electric vehicles (EVs) are estimated as if the vehicles were driven in the same pattern of driving. Six different driving cycles are evaluated, ranging in speed from 7 to 49 miles per hour (mph). These steps are repeated using specifics of fuel composition, electric power mix, and environmental conditions applicable to Chicago, Denver, Los Angeles, and New York in the month of July. The year 2000 emissions differences for each of four regulated pollutants - HC, CO, NO{sub x,} SO{sub x} - are estimated. CO{sub 2} emissions are also estimated. With use of EVs, HC and CO emissions are consistently lowered by 98% or more. CO{sub 2} emissions reductions are uniformly large at low speed, but variable at high speed. It is found that initially introduced EVs could achieve 100% emission reductions in Chicago by using off-peak power from nuclear power plants for EV electricity generation. Emissions reductions occur for all combinations in Los Angeles, and for most combinations in New York, excepting SO{sub x}. NO{sub x} emissions are reduced in all four cities. An ``avoided cost`` value for each regulated pollutant is estimated for each of the cities. The values for each city depend on severity of air quality violations. It is estimated that the emissions reduction value of EVs driven an average of one and one half hours per day in Los Angeles ranges from $1050 to $3,900; $590 to $2100 in New York; $270 to $1200 in Chicago, and $330 to $1250 in Denver (1989$). Assuming a range of about 100 miles in congested conditions with speeds of 10 mph or less, the estimates range from $3600 to $13300 for Los Angeles; $2004 to $7200 for New York; $930 to $2930 for Chicago; and $1120 to $4290 for Denver. Low estimates are obtained using EPA`s draft Mobile5 model for GV emissions, high values by using California`s EMFAC7EP-SCF1 model. The dollar value benefit estimates include no economic value.

  8. Magnitude and value of electric vehicle emissions reductions for six driving cycles in four US cities with varying air quality problems

    SciTech Connect

    Wang, Q. ); Santini, D.L. )

    1992-01-01

    The emissions of logically competing mid-1990 gasoline vehicles (GVs) and electric vehicles (EVs) are estimated as if the vehicles were driven in the same pattern of driving. Six different driving cycles are evaluated, ranging in speed from 7 to 49 miles per hour (mph). These steps are repeated using specifics of fuel composition, electric power mix, and environmental conditions applicable to Chicago, Denver, Los Angeles, and New York in the month of July. The year 2000 emissions differences for each of four regulated pollutants - HC, CO, NO[sub x,] SO[sub x] - are estimated. CO[sub 2] emissions are also estimated. With use of EVs, HC and CO emissions are consistently lowered by 98% or more. CO[sub 2] emissions reductions are uniformly large at low speed, but variable at high speed. It is found that initially introduced EVs could achieve 100% emission reductions in Chicago by using off-peak power from nuclear power plants for EV electricity generation. Emissions reductions occur for all combinations in Los Angeles, and for most combinations in New York, excepting SO[sub x]. NO[sub x] emissions are reduced in all four cities. An avoided cost'' value for each regulated pollutant is estimated for each of the cities. The values for each city depend on severity of air quality violations. It is estimated that the emissions reduction value of EVs driven an average of one and one half hours per day in Los Angeles ranges from $1050 to $3,900; $590 to $2100 in New York; $270 to $1200 in Chicago, and $330 to $1250 in Denver (1989$). Assuming a range of about 100 miles in congested conditions with speeds of 10 mph or less, the estimates range from $3600 to $13300 for Los Angeles; $2004 to $7200 for New York; $930 to $2930 for Chicago; and $1120 to $4290 for Denver. Low estimates are obtained using EPA's draft Mobile5 model for GV emissions, high values by using California's EMFAC7EP-SCF1 model. The dollar value benefit estimates include no economic value.

  9. Onboard power line conditioning system for an electric or hybrid vehicle

    DOEpatents

    Kajouke, Lateef A.; Perisic, Milun

    2016-06-14

    A power line quality conditioning system for a vehicle includes an onboard rechargeable direct current (DC) energy storage system and an onboard electrical system coupled to the energy storage system. The energy storage system provides DC energy to drive an electric traction motor of the vehicle. The electrical system operates in a charging mode such that alternating current (AC) energy from a power grid external to the vehicle is converted to DC energy to charge the DC energy storage system. The electrical system also operates in a vehicle-to-grid power conditioning mode such that DC energy from the DC energy storage system is converted to AC energy to condition an AC voltage of the power grid.

  10. Modeling the Performance and Cost of Lithium-Ion Batteries for Electric-Drive Vehicles - SECOND EDITION

    SciTech Connect

    Nelson, Paul A.; Gallagher, Kevin G.; Bloom, Ira D.; Dees, Dennis W.

    2012-01-01

    This report details the Battery Performance and Cost model (BatPaC) developed at Argonne National Laboratory for lithium-ion battery packs used in automotive transportation. The model designs the battery for a specified power, energy, and type of vehicle battery. The cost of the designed battery is then calculated by accounting for every step in the lithium-ion battery manufacturing process. The assumed annual production level directly affects each process step. The total cost to the original equipment manufacturer calculated by the model includes the materials, manufacturing, and warranty costs for a battery produced in the year 2020 (in 2010 US$). At the time this report is written, this calculation is the only publicly available model that performs a bottom-up lithium-ion battery design and cost calculation. Both the model and the report have been publicly peer-reviewed by battery experts assembled by the U.S. Environmental Protection Agency. This report and accompanying model include changes made in response to the comments received during the peer-review. The purpose of the report is to document the equations and assumptions from which the model has been created. A user of the model will be able to recreate the calculations and perhaps more importantly, understand the driving forces for the results. Instructions for use and an illustration of model results are also presented. Almost every variable in the calculation may be changed by the user to represent a system different from the default values pre-entered into the program. The distinct advantage of using a bottom-up cost and design model is that the entire power-to-energy space may be traversed to examine the correlation between performance and cost. The BatPaC model accounts for the physical limitations of the electrochemical processes within the battery. Thus, unrealistic designs are penalized in energy density and cost, unlike cost models based on linear extrapolations. Additionally, the consequences on

  11. Frequency modulation drive for a piezoelectric motor

    DOEpatents

    Mittas, Anthony

    2001-01-01

    A piezoelectric motor has peak performance at a specific frequency f.sub.1 that may vary over a range of frequencies. A drive system is disclosed for operating such a motor at peak performance without feedback. The drive system consists of the motor and an ac source connected to power the motor, the ac source repeatedly generating a frequency over a range from f.sub.1 -.DELTA.x to f.sub.1 +.DELTA.y.

  12. Driving Sodium-Potassium Pumps With An Oscillating Electric Field: Effects On Muscle Recovery In The Human Biceps Brachii

    NASA Astrophysics Data System (ADS)

    Bovyn, Matt; Chen, Wei; Lanes, Olivia; Mast, Jason

    2013-03-01

    Dr. Chen has developed a technique called synchronization modulation, which uses an oscillating electric field to increase the rate at which the sodium-potassium pumps in the cell membrane work. Because the sodium-potassium pump is integral in the recovery of skeletal muscle fibers after an action potential, we investigated the effects of applying synchronization modulation to muscles which had already undergone fatigue due to repeated action potentials during exercise. Fatigue was induced in human subjects' biceps brachii through isometric contraction. Surface electromyography measurements of fatigue index were used to quantify how the muscle recovered over the minutes following fatigue, both when synchronization modulation was applied and when it was absent. The preliminary results were inconclusive, but it is hoped that in later work it will be shown that applying synchronization modulation is effective in increasing the rate at which the muscle recovers to its initial state. This would demonstrate not only that synchronization modulation can be successfully applied to human muscle, but also that it has many potential applications in sports medicine and novel disease treatments. Work done as part of an REU program at the University of South Florida

  13. Starting Phenomena and Temperature-rise under vvvf Supply of Three-Phase Squirrel-Cage ac Traction Motor of Electric Locomotive

    NASA Astrophysics Data System (ADS)

    Paul, R. N.; Arya, L. D.; Verma, H. K.

    2012-09-01

    In three-phase squirrel-cage ac traction motor, temperature-rise calculation during variable-voltage and variable-frequency starting is of vital importance and has to be predicted and critically examined. Under voltage source inverter supply with PWM, the generation of harmonics by inverter supply reduces the output during starting due to higher harmonic losses, thereby reducing the starting tractive effort in kN on locomotive wheel. Stator and rotor temperature-rises during starting have been determined for average acceleration torque in segmental zone (calculated from variable acceleration) which have been presented in the paper with both copper and aluminium alloy rotor bars.

  14. AC resistance measuring instrument

    DOEpatents

    Hof, P.J.

    1983-10-04

    An auto-ranging AC resistance measuring instrument for remote measurement of the resistance of an electrical device or circuit connected to the instrument includes a signal generator which generates an AC excitation signal for application to a load, including the device and the transmission line, a monitoring circuit which provides a digitally encoded signal representing the voltage across the load, and a microprocessor which operates under program control to provide an auto-ranging function by which range resistance is connected in circuit with the load to limit the load voltage to an acceptable range for the instrument, and an auto-compensating function by which compensating capacitance is connected in shunt with the range resistance to compensate for the effects of line capacitance. After the auto-ranging and auto-compensation functions are complete, the microprocessor calculates the resistance of the load from the selected range resistance, the excitation signal, and the load voltage signal, and displays of the measured resistance on a digital display of the instrument. 8 figs.

  15. AC Resistance measuring instrument

    DOEpatents

    Hof, Peter J.

    1983-01-01

    An auto-ranging AC resistance measuring instrument for remote measurement of the resistance of an electrical device or circuit connected to the instrument includes a signal generator which generates an AC excitation signal for application to a load, including the device and the transmission line, a monitoring circuit which provides a digitally encoded signal representing the voltage across the load, and a microprocessor which operates under program control to provide an auto-ranging function by which range resistance is connected in circuit with the load to limit the load voltage to an acceptable range for the instrument, and an auto-compensating function by which compensating capacitance is connected in shunt with the range resistance to compensate for the effects of line capacitance. After the auto-ranging and auto-compensation functions are complete, the microprocessor calculates the resistance of the load from the selected range resistance, the excitation signal, and the load voltage signal, and displays of the measured resistance on a digital display of the instrument.

  16. DC/DC Power Converter for Super-Capacitor Supplied by Electric Power Splitter

    NASA Astrophysics Data System (ADS)

    Haubert, T.; Mindl, P.

    The aim of the article is design of DC/DC converter and discussing of problematic supply using electric power splitter. The electric power splitter with AC/DC converter is source for the DC/DC converter, which is dedicated for charging and discharging of hybrid car drive super-capacitor energy storage. The electric power splitter is synchronous machine with two rotating parts. First rotor contains permanent magnet and the second rotor contains three-phase windings. The amplitude of output voltage depends on difference between first and second rotor speed. The main role of the DC/DC converter is to optimize energy content in super-capacitor storage used to acceleration and deceleration driving period of the passenger car with hybrid electric vehicle (HEV) drive system using electric power splitter.

  17. Quality-Factor Enhancement of Nanoelectromechanical Systems by Capacitive Driving Beyond Resonance

    NASA Astrophysics Data System (ADS)

    Barois, T.; Perisanu, S.; Poncharal, P.; Vincent, P.; Purcell, S. T.; Ayari, A.

    2016-07-01

    Nanoelectromechanical systems are considered as ultrasensitive devices for mass and force detection. Capacitive actuation is widely used in these devices but is known to degrade the quality factor of the resonator due to dc electrostatic damping. We report the enhancement of the quality factor of SiC vibrating nanowires detected nano-optomechanically and electrically by applying an ac capacitive driving at a frequency above both the resonance frequency and the electrical cutoff frequency. Self-oscillations are demonstrated for optimal conditions. We develop an analytical model of the phenomenon and show that it can lead to an improvement of the force sensitivity.

  18. Control rod drive

    DOEpatents

    Hawke, Basil C.

    1986-01-01

    A control rod drive uses gravitational forces to insert one or more control rods upwardly into a reactor core from beneath the reactor core under emergency conditions. The preferred control rod drive includes a vertically movable weight and a mechanism operatively associating the weight with the control rod so that downward movement of the weight is translated into upward movement of the control rod. The preferred control rod drive further includes an electric motor for driving the control rods under normal conditions, an electrically actuated clutch which automatically disengages the motor during a power failure and a decelerator for bringing the control rod to a controlled stop when it is inserted under emergency conditions into a reactor core.

  19. Digital ac monitor

    DOEpatents

    Hart, G.W.; Kern, E.C. Jr.

    1987-06-09

    An apparatus and method is provided for monitoring a plurality of analog ac circuits by sampling the voltage and current waveform in each circuit at predetermined intervals, converting the analog current and voltage samples to digital format, storing the digitized current and voltage samples and using the stored digitized current and voltage samples to calculate a variety of electrical parameters; some of which are derived from the stored samples. The non-derived quantities are repeatedly calculated and stored over many separate cycles then averaged. The derived quantities are then calculated at the end of an averaging period. This produces a more accurate reading, especially when averaging over a period in which the power varies over a wide dynamic range. Frequency is measured by timing three cycles of the voltage waveform using the upward zero crossover point as a starting point for a digital timer. 24 figs.

  20. Digital ac monitor

    DOEpatents

    Hart, George W.; Kern, Jr., Edward C.

    1987-06-09

    An apparatus and method is provided for monitoring a plurality of analog ac circuits by sampling the voltage and current waveform in each circuit at predetermined intervals, converting the analog current and voltage samples to digital format, storing the digitized current and voltage samples and using the stored digitized current and voltage samples to calculate a variety of electrical parameters; some of which are derived from the stored samples. The non-derived quantities are repeatedly calculated and stored over many separate cycles then averaged. The derived quantities are then calculated at the end of an averaging period. This produces a more accurate reading, especially when averaging over a period in which the power varies over a wide dynamic range. Frequency is measured by timing three cycles of the voltage waveform using the upward zero crossover point as a starting point for a digital timer.

  1. iDriving (Intelligent Driving)

    2012-09-17

    iDriving identifies the driving style factors that have a major impact on fuel economy. An optimization framework is used with the aim of optimizing a driving style with respect to these driving factors. A set of polynomial metamodels is constructed to reflect the responses produced in fuel economy by changing the driving factors. The optimization framework is used to develop a real-time feedback system, including visual instructions, to enable drivers to alter their driving stylesmore » in responses to actual driving conditions to improve fuel efficiency.« less

  2. Electric and hybrid vehicle systems assessment seminar: proceedings

    SciTech Connect

    Not Available

    1984-03-15

    The following twenty papers are included in these proceedings: (1) electric and hybrid vehicle assessment overview, (2) electric and hybrid vehicle systems considerations, (3) advanced vehicle assessment, (4) hybrid vehicle assessment, (5) battery optimization considerations, (6) alkaline battery technology, (7) lead-acid batteries, (8) nickel-iron batteries, (9) zinc-chloride batteries, (10) zinc-bromine batteries, (11) sodium-sulfur batteries, (12) system/battery design interaction for a lithium-method sulfide van battery, (13) iorn-air batteries, (14) aluminium-air cells, (15) fuel cell overview, (16) variable-reluctance motor drives, (17) electric vehicle design, (18) advanced electric vehicle powertrain program, (19) Eaton ac drivetrains, and (20) JET Propulsion Laboratory ac power system. (MOW)

  3. Driving platform for OLED lighting investigations

    NASA Astrophysics Data System (ADS)

    Vogel, Uwe; Elgner, Andreas; Kreye, Daniel; Amelung, Jörg; Scholles, Michael

    2006-08-01

    OLED technology may be excellently suitable for lighting applications by combining high efficiency, cost effective manufacturing and the use of low cost materials. Certain issues remain to be solved so far, including OLED brightness, color, lifetime, large area uniformity and encapsulation. Another aspect, that might be capable in addressing some of the mentioned issues, is OLED lighting electrical driving. We report on the design of a driving platform for OLED lighting test panels or substrates. It is intended for being a test environment for lighting substrates as well as demonstration/presentation environment. It is based on a 128-channel passive-matrix driver/controller ASIC OC2. Its key component is an MSP430-compatible 16-bit micro-controller core including embedded Flash memory (program), EEPROM (parameter), and RAM (data memory). A significant feature of the device is an electronic approach for improving the lifetime/uniformity behavior of connected OLED. The embedded micro-controller is the key to the high versatility of OC2, since by firmware modification it can be adapted to various applications and conditions. Here its application for an OLED lighting driving platform is presented. Major features of this platform are PC-control mode (via USB interface), stand-alone mode (no external control necessary, just power supply), on-board OLED panel parameter storage, flat geometry of OLED lighting panel carrier (board), AC and DC driving regimes, adjustable reverse voltage, dedicated user SW (PC/Windows-based), sub-tile patterning and single sub-tile control, combination of multiple channels for increasing driving current. This publication contains results of the project "High Brightness OLEDs for ICT & Next Generation Lighting Applications" (OLLA), funded by the European Commission.

  4. A Multi-Level Grid Interactive Bi-directional AC/DC-DC/AC Converter and a Hybrid Battery/Ultra-capacitor Energy Storage System with Integrated Magnetics for Plug-in Hybrid Electric Vehicles

    SciTech Connect

    Onar, Omer C

    2011-01-01

    This study presents a bi-directional multi-level power electronic interface for the grid interactions of plug-in hybrid electric vehicles (PHEVs) as well as a novel bi-directional power electronic converter for the combined operation of battery/ultracapacitor hybrid energy storage systems (ESS). The grid interface converter enables beneficial vehicle-to-grid (V2G) interactions in a high power quality and grid friendly manner; i.e, the grid interface converter ensures that all power delivered to/from grid has unity power factor and almost zero current harmonics. The power electronic converter that provides the combined operation of battery/ultra-capacitor system reduces the size and cost of the conventional ESS hybridization topologies while reducing the stress on the battery, prolonging the battery lifetime, and increasing the overall vehicle performance and efficiency. The combination of hybrid ESS is provided through an integrated magnetic structure that reduces the size and cost of the inductors of the ESS converters. Simulation and experimental results are included as prove of the concept presenting the different operation modes of the proposed converters.

  5. CONTROL ROD DRIVE

    DOEpatents

    Chapellier, R.A.

    1960-05-24

    BS>A drive mechanism was invented for the control rod of a nuclear reactor. Power is provided by an electric motor and an outside source of fluid pressure is utilized in conjunction with the fluid pressure within the reactor to balance the loadings on the motor. The force exerted on the drive mechanism in the direction of scramming the rod is derived from the reactor fluid pressure so that failure of the outside pressure source will cause prompt scramming of the rod.

  6. Testing of a direct drive generator for wind turbines

    SciTech Connect

    Sondergaard, L.M.

    1996-12-31

    The normal drive train of a wind turbine consists a gearbox and a 4 to 8 poles asynchronous generator. The gearbox is an expensive and unreliable components and this paper deals with testing of a direct drive synchronous generator for a gearless wind turbine. The Danish company Belt Electric has constructed and manufactured a 27 kW prototype radial flux PM-generator (DD600). They have used cheap hard ferrite magnets in the rotor of this PM-generator. This generator has been tested at Riso and the test results are investigated and analyzed in this paper. The tests have been done with three different load types (1: resistance; 2: diode rectifier, DC-capacitor, resistance; 3: AC-capacitor, diode rectifier, DC-capacitor, resistance). 1 ref., 9 figs., 5 tabs.

  7. Electrical properties of AC{sub 3}B{sub 4}O{sub 12}-type perovskite ceramics with different cation vacancies

    SciTech Connect

    Li, Guizhong; Chen, Zhi; Sun, Xiaojun; Liu, Laijun; Fang, Liang; Elouadi, Brahim

    2015-05-15

    Highlights: • AC{sub 3}B{sub 4}O{sub 12} perovskite with different concentration cation vacancies were prepared. • Cell parameter decreases with the increase of concentration of cation vacancies. • PTCO and CTO remain high dielectric permittivity but depress loss greatly. • Dielectric loss associates with cation vacancies and motion of oxygen vacancies. - Abstract: AC{sub 3}B{sub 4}O{sub 12}-type perovskite CaCu{sub 3}Ti{sub 4}O{sub 12} (CCTO), □{sub 0.34}Pr{sub 0.67}Cu{sub 3}Ti{sub 4}O{sub 12} (PCTO), □{sub 1}Cu{sub 3}Ta{sub 2}Ti{sub 2}O{sub 12} (CTTO), □{sub 2}Cu{sub 2}Ta{sub 4}O{sub 12} (CTO) ceramics with different concentration cation vacancies were prepared through traditional solid state reaction method. X-ray diffraction analysis indicated that CCTO and PCTO are perovskite cubic with space group Im-3 (no. 204) while CTTO and CTO are Pm-3 (no. 200). Cell parameter of the samples dramatically increases with the increase of cation vacancies. Dielectric permittivity of them maintains very high value of ∼10{sup 4} from room temperature to 550 K but the dielectric loss is depressed with the increase of cation vacancies in the same space group. The dielectric properties and conductivity behavior were described by the Debye relaxation and the universal dielectric response, respectively. The effect mechanism of cation vacancy and crystal structure on carrier transposition were discussed.

  8. Analyses of temperature-dependent interface states, series resistances, and AC electrical conductivities of Al/p—Si and Al/Bi4Ti3O12/p—Si structures by using the admittance spectroscopy method

    NASA Astrophysics Data System (ADS)

    Mert, Yıldırım; Perihan, Durmuş; Şemsettin, Altındal

    2013-10-01

    In this study, Al/p—Si and Al/Bi4Ti3O12/p—Si structures are fabricated and their interface states (Nss), the values of series resistance (Rs), and AC electrical conductivity (σac) are obtained each as a function of temperature using admittance spectroscopy method which includes capacitance—voltage (C—V) and conductance—voltage (G—V) measurements. In addition, the effect of interfacial Bi4Ti3O12 (BTO) layer on the performance of the structure is investigated. The voltage-dependent profiles of Nss and Rs are obtained from the high-low frequency capacitance method and the Nicollian method, respectively. Experimental results show that Nss and Rs, as strong functions of temperature and applied bias voltage, each exhibit a peak, whose position shifts towards the reverse bias region, in the depletion region. Such a peak behavior is attributed to the particular distribution of Nss and the reordering and restructuring of Nss under the effect of temperature. The values of activation energy (Ea), obtained from the slope of the Arrhenius plot, of both structures are obtained to be bias voltage-independent, and the Ea of the metal-ferroelectric-semiconductor (MFS) structure is found to be half that of the metal—semiconductor (MS) structure. Furthermore, other main electrical parameters, such as carrier concentration of acceptor atoms (NA), built-in potential (Vbi), Fermi energy (EF), image force barrier lowering (Δ Φb), and barrier height (Φb), are extracted using reverse bias C-2—V characteristics as a function of temperature.

  9. Drugged Driving

    MedlinePlus

    ... Infographics » Drugged Driving Drugged Driving Email Facebook Twitter Text Description of Infographic Top Right Figure : In 2009, ... crash than those who don't smoke. Bottom Text: Develop Social Strategies Offer to be a designated ...

  10. Impaired Driving

    MedlinePlus

    ... Risk Factors BAC Effects Prevention Additional Resources How big is the problem? In 2014, 9,967 people ... Driving: A Threat to Everyone (October 2011) Additional Data Drunk Driving State Data and Maps Motor Vehicle ...

  11. The techniques of metallic foil electrically exploding driving hypervelocity flyer to more than 10 km/s for shock wave physics experiments.

    PubMed

    Wang, Guiji; He, Jia; Zhao, Jianheng; Tan, Fuli; Sun, Chengwei; Mo, Jianjun; Xong, Xin; Wu, Gang

    2011-09-01

    Electrical explosion of metallic foil or wire is widely used to the fields of material science (preparation of nao-meter materials), dynamics of materials, and high energy density physics. In this paper, the techniques of gaining hypervelocity flyer driven by electrical explosion of metallic foil were researched, which are used to study dynamics of materials and hypervelocity impact modeling of space debris. Based on low inductance technologies of pulsed storage energy capacitor, detonator switch and parallel plate transmission lines with solid films insulation, two sets of experimental apparatuses with storage energy of 14.4 kJ and 40 kJ were developed for launching hypervelocity flyer. By means of the diagnostic technologies of velocity interferometer system for any reflectors and fibre-optic pins, the hypervelocity polyester (Mylar) flyers were gained. For the apparatus of 14.4 kJ, flyer of diameter φ6 ~ φ10 mm and thickness of 0.1 ~ 0.2 mm was accelerated to the hypervelocity of 10 ~ 14 km/s. And for the apparatus of 40 kJ, flyer of diameter φ20 ~ 30 mm and thickness of 0.2 mm was launched to the velocity of 5 ~ 8 km/s. The flatness of the flyer is not more than 34 ns for the flyer with diameter of 20 mm, and less than 22 ns for the flyer with diameter of 10 mm. Based on the Lagrange hydrodynamic code, one dimensional simulation was done by introducing database of equation of states, discharging circuit equation and Joule heat equation, and modifying energy equation. The simulation results are well agreed with the experimental results in accelerating processing. The simulation results can provide good advices in designing new experiments and developing new experimental devices. Finally, some experiments of materials dynamics and hypervelocity impact of space debris were done by using the apparatus above. The results show that the apparatus of metallic foil electrically exploding driving hypervelocity flyer is a good and versatile tool for shock dynamics.

  12. The techniques of metallic foil electrically exploding driving hypervelocity flyer to more than 10 km/s for shock wave physics experiments

    NASA Astrophysics Data System (ADS)

    Wang, Guiji; He, Jia; Zhao, Jianheng; Tan, Fuli; Sun, Chengwei; Mo, Jianjun; Xong, Xin; Wu, Gang

    2011-09-01

    Electrical explosion of metallic foil or wire is widely used to the fields of material science (preparation of nao-meter materials), dynamics of materials, and high energy density physics. In this paper, the techniques of gaining hypervelocity flyer driven by electrical explosion of metallic foil were researched, which are used to study dynamics of materials and hypervelocity impact modeling of space debris. Based on low inductance technologies of pulsed storage energy capacitor, detonator switch and parallel plate transmission lines with solid films insulation, two sets of experimental apparatuses with storage energy of 14.4 kJ and 40 kJ were developed for launching hypervelocity flyer. By means of the diagnostic technologies of velocity interferometer system for any reflectors and fibre-optic pins, the hypervelocity polyester (Mylar) flyers were gained. For the apparatus of 14.4 kJ, flyer of diameter ϕ6 ˜ ϕ10 mm and thickness of 0.1 ˜ 0.2 mm was accelerated to the hypervelocity of 10 ˜ 14 km/s. And for the apparatus of 40 kJ, flyer of diameter ϕ20 ˜ 30 mm and thickness of 0.2 mm was launched to the velocity of 5 ˜ 8 km/s. The flatness of the flyer is not more than 34 ns for the flyer with diameter of 20 mm, and less than 22 ns for the flyer with diameter of 10 mm. Based on the Lagrange hydrodynamic code, one dimensional simulation was done by introducing database of equation of states, discharging circuit equation and Joule heat equation, and modifying energy equation. The simulation results are well agreed with the experimental results in accelerating processing. The simulation results can provide good advices in designing new experiments and developing new experimental devices. Finally, some experiments of materials dynamics and hypervelocity impact of space debris were done by using the apparatus above. The results show that the apparatus of metallic foil electrically exploding driving hypervelocity flyer is a good and versatile tool for shock dynamics.

  13. Variation in the electrical properties of 100 V/100 a rated mesh and stripe TDMOSFETs (Trench Double-Diffused MOSFETs) for motor drive applications

    NASA Astrophysics Data System (ADS)

    Na, Kyoung-Il; Kah, Dong-Ha; Kim, Sang-Gi; Koo, Jin-Gun; Kim, Jongdae; Yang, Yil-Suk; Lee, Jin-Ho

    2012-05-01

    The vertical power metal-oxide semiconductor field-effect transistors (MOSFETs) with deep trench structures are the most promising candidates to overcome the trade-off relationship between the ON-resistance (R ON ) and the blocking voltage (BV DS ). Especially, 100 V/100 A rated trench power MOSFETs are used in components of many power systems, such as motors and LED lighting drive ICs, DC-DC converters in electric vehicles, and so on. In this work, we studied variations of the electrical characteristics, such as threshold voltage (V TH ), BV DS , and drain current drivability, with p-well doping concentration via the SILVACO simulator. From simulation results, we found the BV DS and the drain current (I D ) as functions of the p-well doping concentration at an ion implantation energy of 80 keV. With increasing of p-well doping concentration in the guard ring region, both V TH and BV DS slowly increased, but I D decreased, because the boron lateral diffusion during the fabrication process below gate trench region affected the doping concentration of the p-body at the active region. Additionally, 100 V/100 A rated trench double-diffused MOSFETs (TDMOSFETs) with meshes and stripes were successfully developed by using a silicon deep etching process. The variations in the electrical properties, such as V TH , BV DS , and drain current drivability, of the two different kinds of fabricated devices, with cell design and density in TDMOSFETs were also studied. The BV DS and the V TH in the stripe-type TDMOSFET were 110 and 3 V, respectively. However, the V TH of mesh-type device was smaller 0.5 V than that of stripe-type because of corner effect. The BV DS improved about 20 V compared to stripe-type TDMOSFET due to edge termination, and the maximum drain current (I D.MAX ) was improved by about 10% due to an increase in the gate width at the same chip size. These effects were reflected in devices with different cell densities. When the cell density was increased, however

  14. Military Curricula for Vocational & Technical Education. Basic Electricity and Electronics Individualized Learning System. CANTRAC A-100-0010. Module Twelve: Series AC Resistive-Reactive Circuits. Study Booklet.

    ERIC Educational Resources Information Center

    Chief of Naval Education and Training Support, Pensacola, FL.

    This individualized learning module on series alternating current resistive-reactive circuits is one in a series of modules for a course in basic electricity and electronics. The course is one of a number of military-developed curriculum packages selected for adaptation to vocational instructional and curriculum development in a civilian setting.…

  15. Military Curricula for Vocational & Technical Education. Basic Electricity and Electronics Individualized Learning System. CANTRAC A-100-0010. Module Fourteen: Parallel AC Resistive-Reactive Circuits. Study Booklet.

    ERIC Educational Resources Information Center

    Chief of Naval Education and Training Support, Pensacola, FL.

    This individualized learning module on parallel alternating current resistive-reaction circuits is one in a series of modules for a course in basic electricity and electronics. The course is one of a number of military-developed curriculum packages selected for adaptation to vocational instructional and curriculum development in a civilian…

  16. Co-existence of multiple attractors in the PWM controlled DC drives

    NASA Astrophysics Data System (ADS)

    Kundu, Susmita; Kar, Urmila; Chakrabarty, K.

    2013-07-01

    DC shunt and series drives are extensively used in the industry. The occurrence of bifurcation and chaos in dc shunt and permanent magnet drives are well known. It is observed that the behavior of the drives not only depends on the value of system parameters but also on the value of initial conditions. Multiple attractors can exist for same parameter value. Different choice of initial conditions gives different periodic behavior of the system. The drive is intended to operate in a parameter range to give period-1 behavior. We report the existence of sub- harmonic oscillations in the period-1 region of the bifurcation diagram along with co-existing attractor with fractal basin boundaries in PWM controlled dc series drives. The series drive is extensively used in electric traction and other applications. The dc drives are run with dc input voltage. This dc voltage may be derived from a dc source or an ac source with a rectifier. The dc series drive shows different bifurcation behavior when different types of input voltage and switching elements are used. The existence of period-1, period-2 and period-4 orbits are observed with different initial conditions in the desired period-1 region of the bifurcation diagram. The dependence of system's behavior on initial condition may render the system's behavior unpredictable. These phenomena may have serious implication in performance.

  17. Single channel double-duct liquid metal electrical generator using a magnetohydrodynamic device

    DOEpatents

    Haaland, C.M.; Deeds, W.E.

    1999-07-13

    A single channel double-duct liquid metal electrical generator using a magnetohydrodynamic (MHD) device. The single channel device provides useful output AC electric energy. The generator includes a two-cylinder linear-piston engine which drives liquid metal in a single channel looped around one side of the MHD device to form a double-duct contra-flowing liquid metal MHD generator. A flow conduit network and drive mechanism are provided for moving liquid metal with an oscillating flow through a static magnetic field to produce useful AC electric energy at practical voltages and currents. Variable stroke is obtained by controlling the quantity of liquid metal in the channel. High efficiency is obtained over a wide range of frequency and power output. 5 figs.

  18. Single channel double-duct liquid metal electrical generator using a magnetohydrodynamic device

    DOEpatents

    Haaland, Carsten M.; Deeds, W. Edward

    1999-01-01

    A single channel double-duct liquid metal electrical generator using a magnetohydrodynamic (MHD) device. The single channel device provides useful output AC electric energy. The generator includes a two-cylinder linear-piston engine which drives liquid metal in a single channel looped around one side of the MHD device to form a double-duct contra-flowing liquid metal MHD generator. A flow conduit network and drive mechanism are provided for moving liquid metal with an oscillating flow through a static magnetic field to produce useful AC electric energy at practical voltages and currents. Variable stroke is obtained by controlling the quantity of liquid metal in the channel. High efficiency is obtained over a wide range of frequency and power output.

  19. Emergence of periodic order in electric-field-driven planar nematic liquid crystals: an exclusive ac effect absent in static fields.

    PubMed

    Krishnamurthy, K S; Kumar, Pramoda

    2007-11-01

    We report, for a nematic liquid crystal with a low conductivity anisotropy, an ac field generated transition from a uniformly planar to a periodically modulated director configuration with the wave vector parallel to the initial director. Significantly, with unblocked electrodes, this instability is not excited by dc fields. Additionally, in very low frequency square wave fields, it occurs transiently after each polarity reversal, vanishing completely during field constancy. The time of occurrence of maximum distortion after polarity reversal decreases exponentially with voltage. The time dependence of optical phase change during transient distortion is nearly Gaussian. The pattern threshold Vc is linear in sqrt[f], f denoting the frequency; the critical wave number qc of the modulation scales nearly linearly as sqrt[f] to a peak at approximately 50 Hz before falling slightly thereafter. The observed Vc(f) and qc(f) characteristics differ from the predictions of the standard model (SM). The instability may be interpreted as a special case of the Carr-Helfrich distortion suppressed in static fields due to weak charge focusing and strong charge injection. Its transient nature in the low frequency regime is suggestive of the possible role of gradient flexoelectric effect in its occurrence. The study includes measurement of certain elastic and viscosity parameters relevant to the application of the SM. PMID:18233671

  20. On the variation in the electrical properties and ac conductivity of through-thickness nano-porous anodic alumina with temperature

    NASA Astrophysics Data System (ADS)

    Tahir, Mahmood; Mehmood, Mazhar; Nadeem, Muhammad; Waheed, Abdul; Tanvir, Muhammad Tauseef

    2013-09-01

    The electrical response of self-organized through-thickness anodic alumina with hexagonal arrangement of cylindrical pores has been studied as a function of temperature. Mechanically stable thick porous anodic alumina was prepared, by through-thickness anodic oxidation of aluminum sheet in sulfuric acid, with extremely high aspect ratio pores exhibiting fairly uniform diameter and interpore distance. It was observed that the electrical properties of through-thickness anodic alumina are very sensitive to minute changes in temperature and the role of surface conductivity in governing its electrical response cannot be overlooked. At high frequencies, intrinsic dielectric response of anodic alumina was dominant. The frequency-dependent conductivity behavior at low and intermediate frequencies was explained on the basis of correlated barrier hopping (CBH) and quantum mechanical tunneling (QMT) models, respectively. Experimental data was modeled using an equivalent circuit consisting of Debye circuit, for bulk alumina, parallel to surface conduction path. The surface conduction was primarily based on two circuits in series, each with a parallel arrangement of a resistor and a constant phase element. This suggested heterogeneity in alumina pore surface, possibly related with islands of physisorbed water separated by the regions of chemisorbed water. Temperature dependence of some circuit elements has been analyzed to express different charge migration phenomena occurring in nano-porous anodic alumina.

  1. QPSK modulation for AC-power-signal-biased visible light communication system

    NASA Astrophysics Data System (ADS)

    Liu, Yu-Feng; Yeh, Chien-Hung; Chow, Chi-Wai; Liu, Yang

    2013-01-01

    With the integration of light emitting diode (LED), visible light communication (VLC) can provide wireless communication link using the lightning system. Due to the consideration of power efficiency, AC-LED has the design of reducing energy waste with alternating current from the power outlet. In this work, we propose an AC-power-signalbiased system that provides communication on both DC-LED and AC-LED. The bias circuit is designed to combine ACpower signal and the message signal with QPSK format. This driving scheme needs no AC-to-DC converters and it is suitable for driving AC LED. Synchronization is completed to avoid threshold effect of LED.

  2. Pile Driving

    NASA Technical Reports Server (NTRS)

    1987-01-01

    Machine-oriented structural engineering firm TERA, Inc. is engaged in a project to evaluate the reliability of offshore pile driving prediction methods to eventually predict the best pile driving technique for each new offshore oil platform. Phase I Pile driving records of 48 offshore platforms including such information as blow counts, soil composition and pertinent construction details were digitized. In Phase II, pile driving records were statistically compared with current methods of prediction. Result was development of modular software, the CRIPS80 Software Design Analyzer System, that companies can use to evaluate other prediction procedures or other data bases.

  3. ACS: ALMA Common Software

    NASA Astrophysics Data System (ADS)

    Chiozzi, Gianluca; Šekoranja, Matej

    2013-02-01

    ALMA Common Software (ACS) provides a software infrastructure common to all ALMA partners and consists of a documented collection of common patterns and components which implement those patterns. The heart of ACS is based on a distributed Component-Container model, with ACS Components implemented as CORBA objects in any of the supported programming languages. ACS provides common CORBA-based services such as logging, error and alarm management, configuration database and lifecycle management. Although designed for ALMA, ACS can and is being used in other control systems and distributed software projects, since it implements proven design patterns using state of the art, reliable technology. It also allows, through the use of well-known standard constructs and components, that other team members whom are not authors of ACS easily understand the architecture of software modules, making maintenance affordable even on a very large project.

  4. 49 CFR 538.6 - Measurement of driving range.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... set forth in 40 CFR part 600. The driving range of a passenger automobile model type using electricity... 49 Transportation 6 2014-10-01 2014-10-01 false Measurement of driving range. 538.6 Section 538.6... Measurement of driving range. The driving range of a passenger automobile model type not using electricity...

  5. 49 CFR 538.6 - Measurement of driving range.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... set forth in 40 CFR part 600. The driving range of a passenger automobile model type using electricity... 49 Transportation 6 2013-10-01 2013-10-01 false Measurement of driving range. 538.6 Section 538.6... Measurement of driving range. The driving range of a passenger automobile model type not using electricity...

  6. 49 CFR 538.6 - Measurement of driving range.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... set forth in 40 CFR part 600. The driving range of a passenger automobile model type using electricity... 49 Transportation 6 2010-10-01 2010-10-01 false Measurement of driving range. 538.6 Section 538.6... Measurement of driving range. The driving range of a passenger automobile model type not using electricity...

  7. 49 CFR 538.6 - Measurement of driving range.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... set forth in 40 CFR part 600. The driving range of a passenger automobile model type using electricity... 49 Transportation 6 2012-10-01 2012-10-01 false Measurement of driving range. 538.6 Section 538.6... Measurement of driving range. The driving range of a passenger automobile model type not using electricity...

  8. 49 CFR 538.5 - Minimum driving range.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 6 2010-10-01 2010-10-01 false Minimum driving range. 538.5 Section 538.5... Minimum driving range. (a) The minimum driving range that a passenger automobile must have in order to be... electricity. (b) The minimum driving range that a passenger automobile using electricity as an...

  9. 49 CFR 538.5 - Minimum driving range.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 6 2012-10-01 2012-10-01 false Minimum driving range. 538.5 Section 538.5... Minimum driving range. (a) The minimum driving range that a passenger automobile must have in order to be... electricity. (b) The minimum driving range that a passenger automobile using electricity as an...

  10. 49 CFR 538.5 - Minimum driving range.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 6 2014-10-01 2014-10-01 false Minimum driving range. 538.5 Section 538.5... Minimum driving range. (a) The minimum driving range that a passenger automobile must have in order to be... electricity. (b) The minimum driving range that a passenger automobile using electricity as an...

  11. 49 CFR 538.5 - Minimum driving range.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 6 2011-10-01 2011-10-01 false Minimum driving range. 538.5 Section 538.5... Minimum driving range. (a) The minimum driving range that a passenger automobile must have in order to be... electricity. (b) The minimum driving range that a passenger automobile using electricity as an...

  12. 49 CFR 538.6 - Measurement of driving range.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... set forth in 40 CFR part 600. The driving range of a passenger automobile model type using electricity... 49 Transportation 6 2011-10-01 2011-10-01 false Measurement of driving range. 538.6 Section 538.6... Measurement of driving range. The driving range of a passenger automobile model type not using electricity...

  13. 49 CFR 538.5 - Minimum driving range.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 6 2013-10-01 2013-10-01 false Minimum driving range. 538.5 Section 538.5... Minimum driving range. (a) The minimum driving range that a passenger automobile must have in order to be... electricity. (b) The minimum driving range that a passenger automobile using electricity as an...

  14. The Bearingless Electrical Machine

    NASA Technical Reports Server (NTRS)

    Bichsel, J.

    1992-01-01

    Electromagnetic bearings allow the suspension of solids. For rotary applications, the most important physical effect is the force of a magnetic circuit to a high permeable armature, called the MAXWELL force. Contrary to the commonly used MAXWELL bearings, the bearingless electrical machine will take advantage of the reaction force of a conductor carrying a current in a magnetic field. This kind of force, called Lorentz force, generates the torque in direct current, asynchronous and synchronous machines. The magnetic field, which already exists in electrical machines and helps to build up the torque, can also be used for the suspension of the rotor. Besides the normal winding of the stator, a special winding was added, which generates forces for levitation. So a radial bearing, which is integrated directly in the active part of the machine, and the motor use the laminated core simultaneously. The winding was constructed for the levitating forces in a special way so that commercially available standard ac inverters for drives can be used. Besides wholly magnetic suspended machines, there is a wide range of applications for normal drives with ball bearings. Resonances of the rotor, especially critical speeds, can be damped actively.

  15. Small-Signal ac Analysis

    NASA Technical Reports Server (NTRS)

    Jagielski, James M.; Chen, Jess

    1987-01-01

    Program simulates power circuits and systems. Small Signal A.C. Analysis program (SSAC) valuable tool for design and analysis of electrical-power-system circuits. By combining "black box" power-system components operating in specified manner, user characterizes system modeled. Menu-driven program proved simple and cost effective in development and modification of arbitrary power-system configurations. Package includes sample data from Dynamic Explorer satellite family. Results compared favorable to calculations from such general circuit-analysis programs as SPICE. Written in FORTRAN 77.

  16. CONTROL ROD DRIVE MECHANISM FOR A NUCLEAR REACTOR

    DOEpatents

    Hawke, B.C.; Liederbach, F.J.; Lones, W.

    1963-05-14

    A lead-screw-type control rod drive featuring an electric motor and a fluid motor arranged to provide a selectably alternative driving means is described. The electric motor serves to drive the control rod slowly during normal operation, while the fluid motor, assisted by an automatic declutching of the electric motor, affords high-speed rod insertion during a scram. (AEC)

  17. Distracted Driving

    MedlinePlus

    ... combines all three types of distraction. 3 How big is the problem? Deaths In 2013, 3,154 ... European countries. More A CDC study analyzed 2011 data on distracted driving, including talking on a cell ...

  18. Lipid nanotube formation using space-regulated electric field above interdigitated electrodes.

    PubMed

    Bi, Hongmei; Fu, Dingguo; Wang, Lei; Han, Xiaojun

    2014-04-22

    Lipid nanotubes have great potential in biology and nanotechnology. Here we demonstrate a method to form lipid nanotubes using space-regulated AC electric fields above coplanar interdigitated electrodes. The AC electric field distribution can be regulated by solution height above the electrodes. The ratio of field component in x axis (Ex) to field component in z axis (Ez) increases dramatically at solution height below 50 μm; therefore, at lower solution height, the force from Ex predominantly drives lipids to form lipid nanotubes along with the electric field direction. The forces exerted on the lipid nanotube during its formation were analyzed in detail, and an equation was obtained to describe the relationship among nanotube length and field frequency, amplitude, and time. We believe that the presented approach opens a way to design and prepare nanoscale materials with unique structural and functional properties using space-regulated electric fields.

  19. U.S. DRIVE

    SciTech Connect

    2012-03-16

    U.S. DRIVE, which stands for United States Driving Research and Innovation for Vehicle efficiency and Energy sustainability, is an expanded government-industry partnership among the U.S. Department of Energy; USCAR, representing Chrysler Group LLC, Ford Motor Company and General Motors; Tesla Motors; five energy companies – BP America, Chevron Corporation, ConocoPhillips, ExxonMobil Corporation, and Shell Oil Products US; two utilities – Southern California Edison and Michigan-based DTE Energy; and the Electric Power Research Institute (EPRI). The U.S. DRIVE mission is to accelerate the development of pre-competitive and innovative technologies to enable a full range of affordable and clean advanced light-duty vehicles, as well as related energy infrastructure.

  20. Basic concepts of induced AC voltages on pipelines

    SciTech Connect

    Kirkpatrick, E.L.

    1995-07-01

    The phenomena of induced AC on pipelines sharing common rights-of-way with overhead high-voltage electrical transmission power lines is discussed. Basic concepts and techniques for personnel safety and some pipeline protective measures are reviewed.

  1. Variable frequency drive applications guide

    SciTech Connect

    Laloudakis, D.J.

    1991-10-01

    Traditionally, fans and pumps have been designed to be capable of handling the maximum demand of the system in which they are installed. However, quite often the actual demand can vary and it can be much lower than the original design capacity. These situations have been corrected in the past through additions of outlet dampers to fans or throttling valves to pumps. While these can be effective and simple controls they severely affect the efficiency of the system. Variable frequency (speed) is the most efficient means of capacity control. The most cost effective method of achieving variable speed capacity control is using AC adjustable frequency drives. AC adjustable frequency controls convert any fixed speed AC motor into an adjustable speed device. Adjusting the speed of a motor, by controlling the frequency of the AC power to that motor, reduces its horsepower requirements. According to pump and fan laws, capacity is proportional to speed while horsepower is proportional to the cube of the speed. Therefore, by reducing the speed of an AC motor by 20 percent the horsepower requirement is reduced by nearly 50 percent. Reduced speed through variable frequency control allows for flexibility of meeting changing weather and comfort requirements without operating costly equipment at full capacity.

  2. ac electroosmosis in rectangular microchannels.

    PubMed

    Campisi, Michele; Accoto, Dino; Dario, Paolo

    2005-11-22

    Motivated by the growing interest in ac electroosmosis as a reliable no moving parts strategy to control fluid motion in microfluidic devices for biomedical applications, such as lab-on-a-chip, we study transient and steady-state electrokinetic phenomena (electroosmosis and streaming currents) in infinitely extended rectangular charged microchannels. With the aid of Fourier series and Laplace transforms we provide a general formal solution of the problem, which is used to study the time-dependent response to sudden ac applied voltage differences in case of finite electric double layer. The Debye-Huckel approximation has been adopted to allow for an algebraic solution of the Poisson-Boltzmann problem in Fourier space. We obtain the expressions of flow velocity profiles, flow rates, streaming currents, as well as expressions of the complex hydraulic and electrokinetic conductances. We analyze in detail the dependence of the electrokinetic conductance on the extension of linear dimensions relative to the Debye length, with an eye on finite electric double layer effects. PMID:16351310

  3. Gear Drive Testing

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Philadelphia Gear Corporation used two COSMIC computer programs; one dealing with shrink fit analysis and the other with rotor dynamics problems in computerized design and test work. The programs were used to verify existing in-house programs to insure design accuracy by checking its company-developed computer methods against procedures developed by other organizations. Its specialty is in custom units for unique applications, such as Coast Guard ice breaking ships, steel mill drives, coal crusher, sewage treatment equipment and electricity.

  4. 40 CFR 86.167-17 - AC17 Air Conditioning Emissions Test Procedure.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... New Otto-Cycle Complete Heavy-Duty Vehicles; Test Procedures § 86.167-17 AC17 Air Conditioning...-conditioning cycle, a 30-minute soak period under simulated solar heat, followed by measurement of emissions over an SC03 drive cycle and a Highway Fuel Economy Driving Schedule (HFET) drive cycle. The vehicle...

  5. PtCu substrates subjected to AC and DC electric fields in a solution of benzene sulfonic acid-phenol as novel batteries and their use in glucose biofuel cells

    NASA Astrophysics Data System (ADS)

    Ammam, Malika; Fransaer, Jan

    2013-11-01

    We describe how bi-metal PtCu connected wires, immersed in a solution of benzene sulfonic acid (BSA)-phenol (P) or 2,2‧-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS)-phenol (P), then subjected to simultaneous alternating current (AC) and direct current (DC) electric fields generate power. We discovered that PtCu substrate covered by the deposit containing (BSA-PP-Pt-Cu), abbreviated as PtCu(BSA-PP-Pt-Cu) electrode, plays the role of a substantial anode and cathode. The latter was related to the formation of micro-batteries in the deposited film (BSA-PP-Pt-Cu) that are able to take or deliver electrons from the deposited Pt and Cu, respectively. PP-BSA plays probably the role of bridge for proton conduction in the formed micro-batteries. The power density of the fuel cell (FC)-based PtCu(BSA-PP-Pt-Cu) anode and PtCu(BSA-PP-Pt-Cu) cathode in phosphate buffer solution pH 7.4 at room temperature reaches ˜10.8 μW mm-2. Addition of enzymes, glucose oxidase at the anode and laccase at the cathode and, replacement of BSA by ABTS at the cathode in the deposited films increases the power density to 13.3 μW mm-2. This new procedure might be of great relevance for construction of a new generation of FCs operating at mild conditions or boost the power outputs of BFCs and make them suitable for diverse applications.

  6. High voltage AC/AC electrochemical capacitor operating at low temperature in salt aqueous electrolyte

    NASA Astrophysics Data System (ADS)

    Abbas, Qamar; Béguin, François

    2016-06-01

    We demonstrate that an activated carbon (AC)-based electrochemical capacitor implementing aqueous lithium sulfate electrolyte in 7:3 vol:vol water/methanol mixture can operate down to -40 °C with good electrochemical performance. Three-electrode cell investigations show that the faradaic contributions related with hydrogen chemisorption in the negative AC electrode are thermodynamically unfavored at -40 °C, enabling the system to work as a typical electrical double-layer (EDL) capacitor. After prolonged floating of the AC/AC capacitor at 1.6 V and -40°C, the capacitance, equivalent series resistance and efficiency remain constant, demonstrating the absence of ageing related with side redox reactions at this temperature. Interestingly, when temperature is increased back to 24 °C, the redox behavior due to hydrogen storage reappears and the system behaves as a freshly prepared one.

  7. Electric avenues

    SciTech Connect

    Stone, P.; Chang, A.

    1994-12-31

    Highly efficient electric drive technology developed originally for defense applications is being applied to the development of all electric shuttle buses for the San Jose International Airport. An innovative opportunity charging system using induction chargers will be incorporated to extend operation hours. The project, if successful, is expected to reduce pollution at the airport and generate jobs for displaced defense workers.

  8. AC magnetohydrodynamic microfluidic switch

    SciTech Connect

    Lemoff, A V; Lee, A P

    2000-03-02

    A microfluidic switch has been demonstrated using an AC Magnetohydrodynamic (MHD) pumping mechanism in which the Lorentz force is used to pump an electrolytic solution. By integrating two AC MHD pumps into different arms of a Y-shaped fluidic circuit, flow can be switched between the two arms. This type of switch can be used to produce complex fluidic routing, which may have multiple applications in {micro}TAS.

  9. The AC/DCs of Electricity.

    ERIC Educational Resources Information Center

    Calhoun, Michael J.

    1994-01-01

    Describes an activity that allows students to use a rectifier circuit to convert alternating current into direct current. Also informs teachers of how to obtain most of the equipment needed for free. (ZWH)

  10. UPS with input commutation between ac and dc sources of power

    SciTech Connect

    Severinsky, A.J.

    1993-08-31

    An uninterruptible power supply is described, said power supply comprising: AC input terminal means for receiving a first AC voltage from an AC power source; DC input terminal means for receiving a first DC voltage from a DC power source; AC output terminal means for connecting to a load; converter means for converting said first AC voltage to a second DC voltage across electrical charge storage means coupled to said converter means, said second DC voltage being larger than the maximum peak voltage of said first AC voltage and said first DC voltage; switching means coupled to said AC power source and said DC power source for selectively connecting said AC power source or said DC power source to said converter means; inverter means coupled to said electrical charge storage means for receiving said second DC voltage and inverting said second DC voltage to a second AC voltage, said second AC voltage being coupled to said AC output terminal means; and control means coupled to said switching means for controlling the operation of said switching means, said control means operating said switching means to connect said AC power source to said converter means only when said first AC voltage is within a predetermined range and operating to connect said DC power source to said converter means when said first AC voltage is outside of said range.

  11. Isolation of sequences flanking Ac insertion sites by Ac casting.

    PubMed

    Wang, Dafang; Peterson, Thomas

    2013-01-01

    Localizing Ac insertions is a fundamental task in studying Ac-induced mutation and chromosomal rearrangements involving Ac elements. Researchers may sometimes be faced with the situation in which the sequence flanking one side of an Ac/Ds element is known, but the other flank is unknown. Or, a researcher may have a small sequence surrounding the Ac/Ds insertion site and needs to obtain additional flanking genomic sequences. One way to rapidly clone unknown Ac/Ds flanking sequences is via a PCR-based method termed Ac casting. This approach utilizes the somatic transposition activity of Ac during plant development, and provides an efficient means for short-range genome walking. Here we describe the principle of Ac casting, and show how it can be applied to isolate Ac macrotransposon insertion sites.

  12. Recent applications of AC electrokinetics in biomolecular analysis on microfluidic devices.

    PubMed

    Sasaki, Naoki

    2012-01-01

    AC electrokinetics is a generic term that refers to an induced motion of particles and fluids under nonuniform AC electric fields. The AC electric fields are formed by application of AC voltages to microelectrodes, which can be easily integrated into microfluidic devices by standard microfabrication techniques. Moreover, the magnitude of the motion is large enough to control the mass transfer on the devices. These advantages are attractive for biomolecular analysis on the microfluidic devices, in which the characteristics of small space and microfluidics have been mainly employed. In this review, I describe recent applications of AC electrokinetics in biomolecular analysis on microfluidic devices. The applications include fluid pumping and mixing by AC electrokinetic flow, and manipulation of biomolecules such as DNA and proteins by various AC electrokinetic techniques. Future prospects for highly functional biomolecular analysis on microfluidic devices with the aid of AC electrokinetics are also discussed.

  13. Efficient Driving of Piezoelectric Transducers Using a Biaxial Driving Technique

    PubMed Central

    2015-01-01

    Efficient driving of piezoelectric materials is desirable when operating transducers for biomedical applications such as high intensity focused ultrasound (HIFU) or ultrasound imaging. More efficient operation reduces the electric power required to produce the desired bioeffect or contrast. Our preliminary work [Cole et al. Journal of Physics: Condensed Matter. 2014;26(13):135901.] suggested that driving transducers by applying orthogonal electric fields can significantly reduce the coercivity that opposes ferroelectric switching. We present here the experimental validation of this biaxial driving technique using piezoelectric ceramics typically used in HIFU. A set of narrow-band transducers was fabricated with two sets of electrodes placed in an orthogonal configuration (following the propagation and the lateral mode). The geometry of the ceramic was chosen to have a resonance frequency similar for the propagation and the lateral mode. The average (± s.d.) resonance frequency of the samples was 465.1 (± 1.5) kHz. Experiments were conducted in which each pair of electrodes was driven independently and measurements of effective acoustic power were obtained using the radiation force method. The efficiency (acoustic/electric power) of the biaxial driving method was compared to the results obtained when driving the ceramic using electrodes placed only in the pole direction. Our results indicate that the biaxial method increases efficiency from 50% to 125% relative to the using a single electric field. PMID:26418550

  14. Efficient Driving of Piezoelectric Transducers Using a Biaxial Driving Technique.

    PubMed

    Pichardo, Samuel; Silva, Rafael R C; Rubel, Oleg; Curiel, Laura

    2015-01-01

    Efficient driving of piezoelectric materials is desirable when operating transducers for biomedical applications such as high intensity focused ultrasound (HIFU) or ultrasound imaging. More efficient operation reduces the electric power required to produce the desired bioeffect or contrast. Our preliminary work [Cole et al. Journal of Physics: Condensed Matter. 2014;26(13):135901.] suggested that driving transducers by applying orthogonal electric fields can significantly reduce the coercivity that opposes ferroelectric switching. We present here the experimental validation of this biaxial driving technique using piezoelectric ceramics typically used in HIFU. A set of narrow-band transducers was fabricated with two sets of electrodes placed in an orthogonal configuration (following the propagation and the lateral mode). The geometry of the ceramic was chosen to have a resonance frequency similar for the propagation and the lateral mode. The average (± s.d.) resonance frequency of the samples was 465.1 (± 1.5) kHz. Experiments were conducted in which each pair of electrodes was driven independently and measurements of effective acoustic power were obtained using the radiation force method. The efficiency (acoustic/electric power) of the biaxial driving method was compared to the results obtained when driving the ceramic using electrodes placed only in the pole direction. Our results indicate that the biaxial method increases efficiency from 50% to 125% relative to the using a single electric field.

  15. Input Power Quality Improvement in Switched Reluctance Motor Drive using Minnesota Rectifier

    NASA Astrophysics Data System (ADS)

    Singh, B.; Rajesh, M.

    2013-09-01

    This paper deals with an input power quality improvement in a midpoint converter based switched reluctance motor (SRM) drive at ac mains using Minnesota rectifier. Normally a midpoint converter is used as a power converter for SRM drive. Conventionally three phase ac mains fed bridge rectifier is used as a dc source to feed this power converter which produces high content of harmonics at ac mains with a very low power factor. The proposed Minnesota rectifier with a midpoint converter fed SRM drive improves the power factor at ac mains with low current harmonics. This method provides constant dc link voltage and balanced capacitor voltages of the midpoint converter. The Minnesota rectifier fed SRM drive is modelled and its performance is simulated in Matlab/Simulink environment. The performance of Minnesota rectifier is compared with a conventional bridge topology for SRM drive to demonstrate improved power quality at ac mains.

  16. The Thermodynamics of Drunk Driving

    NASA Astrophysics Data System (ADS)

    Thompson, Robert Q.

    1997-05-01

    Chemical and instrumental tests for driving under the influence of alcohol (DUI) measure the concentration of ethanol in the breath (BrAC), while state DUI laws are described in terms of blood alcohol concentration (BAC). Consequently, accurate and fair conversion from BrAC to BAC is crucial to the judicial process. Theoretical treatment of the water-air-ethanol equilibrium system and the related blood-breath-ethanol system, based on principles from general chemistry and biology, yields an equation relating the ratio of BAC to BrAC to the absolute temperature of the breath, the fraction of water in the blood, and the enthalpy and entropy of vaporization of ethanol from aqueous solution. The model equation predicts an average value for the ratio of 2350+100, not significantly different from reported experimental values. An exponential temperature dependence is predicted and has been confirmed experimentally as well. Biological, chemical, and instrumental variables are described along with their contributions to the overall uncertainty in the value of BrAC/BAC. While the forensic science community uses, and debates, a fixed ratio of 2100, the theoretical model suggests that a value of 1880 should be used to reduce the fraction of false positives to <1%.

  17. AC power generation from microbial fuel cells

    NASA Astrophysics Data System (ADS)

    Lobo, Fernanda Leite; Wang, Heming; Forrestal, Casey; Ren, Zhiyong Jason

    2015-11-01

    Microbial fuel cells (MFCs) directly convert biodegradable substrates to electricity and carry good potential for energy-positive wastewater treatment. However, the low and direct current (DC) output from MFC is not usable for general electronics except small sensors, yet commercial DC-AC converters or inverters used in solar systems cannot be directly applied to MFCs. This study presents a new DC-AC converter system for MFCs that can generate alternating voltage in any desired frequency. Results show that AC power can be easily achieved in three different frequencies tested (1, 10, 60 Hz), and no energy storage layer such as capacitors was needed. The DC-AC converter efficiency was higher than 95% when powered by either individual MFCs or simple MFC stacks. Total harmonic distortion (THD) was used to investigate the quality of the energy, and it showed that the energy could be directly usable for linear electronic loads. This study shows that through electrical conversion MFCs can be potentially used in household electronics for decentralized off-grid communities.

  18. "Fan-Tip-Drive" High-Power-Density, Permanent Magnet Electric Motor and Test Rig Designed for a Nonpolluting Aircraft Propulsion Program

    NASA Technical Reports Server (NTRS)

    Brown, Gerald V.; Kascak, Albert F.

    2004-01-01

    A scaled blade-tip-drive test rig was designed at the NASA Glenn Research Center. The rig is a scaled version of a direct-current brushless motor that would be located in the shroud of a thrust fan. This geometry is very attractive since the allowable speed of the armature is approximately the speed of the blade tips (Mach 1 or 1100 ft/s). The magnetic pressure generated in the motor acts over a large area and, thus, produces a large force or torque. This large force multiplied by the large velocity results in a high-power-density motor.

  19. Tevatron AC dipole system

    SciTech Connect

    Miyamoto, R.; Kopp, S.E.; Jansson, A.; Syphers, M.J.; /Fermilab

    2007-06-01

    The AC dipole is an oscillating dipole magnet which can induce large amplitude oscillations without the emittance growth and decoherence. These properties make it a good tool to measure optics of a hadron synchrotron. The vertical AC dipole for the Tevatron is powered by an inexpensive high power audio amplifier since its operating frequency is approximately 20 kHz. The magnet is incorporated into a parallel resonant system to maximize the current. The use of a vertical pinger magnet which has been installed in the Tevatron made the cost relatively inexpensive. Recently, the initial system was upgraded with a more powerful amplifier and oscillation amplitudes up to 2-3{sigma} were achieved with the 980 GeV proton beam. This paper discusses details of the Tevatron AC dipole system and also shows its test results.

  20. AC-3 audio coder

    NASA Astrophysics Data System (ADS)

    Todd, Craig

    1995-12-01

    AC-3 is a system for coding up to 5.1 channels of audio into a low bit-rate data stream. High quality may be obtained with compression ratios approaching 12-1 for multichannel audio programs. The high compression ratio is achieved by methods which do not increase decoder memory, and thus cost. The methods employed include: the transmission of a high frequency resolution spectral envelope; and a novel forward/backward adaptive bit allocation algorithm. In order to satisfy practical requirements of an emissions coder, the AC-3 syntax includes a number of features useful to broadcasters and consumers. These features include: loudness uniformity between programs; dynamic range control; and broadcaster control of downmix coefficients. The AC-3 coder has been formally selected for inclusion of the U.S. HDTV broadcast standard, and has been informally selected for several additional applications.

  1. Introducing AC Inductive Reactance with a Power Tool

    ERIC Educational Resources Information Center

    Bryant, Wesley; Baker, Blane

    2016-01-01

    The concept of reactance in AC electrical circuits is often non-intuitive and difficult for students to grasp. In order to address this lack of conceptual understanding, classroom exercises compare the predicted resistance of a power tool, based on electrical specifications, to measured resistance. Once students discover that measured resistance…

  2. ac bidirectional motor controller

    NASA Technical Reports Server (NTRS)

    Schreiner, K.

    1988-01-01

    Test data are presented and the design of a high-efficiency motor/generator controller at NASA-Lewis for use with the Space Station power system testbed is described. The bidirectional motor driver is a 20 kHz to variable frequency three-phase ac converter that operates from the high-frequency ac bus being designed for the Space Station. A zero-voltage-switching pulse-density-modulation technique is used in the converter to shape the low-frequency output waveform.

  3. Wind turbine ring/shroud drive system

    DOEpatents

    Blakemore, Ralph W.

    2005-10-04

    A wind turbine capable of driving multiple electric generators having a ring or shroud structure for reducing blade root bending moments, hub loads, blade fastener loads and pitch bearing loads. The shroud may further incorporate a ring gear for driving an electric generator. In one embodiment, the electric generator may be cantilevered from the nacelle such that the gear on the generator drive shaft is contacted by the ring gear of the shroud. The shroud also provides protection for the gearing and aids in preventing gear lubricant contamination.

  4. Novel method for driving the ultrasonic motor.

    PubMed

    Kim, Hyeoung woo; Dong, Shuxiang; Laoratanakul, Pitak; Uchino, Kenji; Park, Tae gone

    2002-10-01

    This paper reports a novel driving method for an annular plate-type ultrasonic motor. Instead of the direct current/alternating current (DC/AC) converter type driver using conventional electromagnetic transformer, a compact disc-type piezoelectric transformer is used to obtain high voltage output for driving the ultrasonic motor. The piezoelectric transformer is operated in the radial vibration mode at resonance frequency close to the resonance frequency of the ultrasonic motor. Later, it was found that the piezoelectric transformer could drive the ultrasonic motor, even if their resonance frequencies are not exactly the same by incorporating the matching network in the circuit. The maximum speed of the ultrasonic motor obtained by using this driving method is over 300 rpm. It is believed that the results of this study will have impact on the integration and miniaturization of the ultrasonic motor and its driving circuit.

  5. Novel method for driving the ultrasonic motor.

    PubMed

    Kim, Hyeoung woo; Dong, Shuxiang; Laoratanakul, Pitak; Uchino, Kenji; Park, Tae gone

    2002-10-01

    This paper reports a novel driving method for an annular plate-type ultrasonic motor. Instead of the direct current/alternating current (DC/AC) converter type driver using conventional electromagnetic transformer, a compact disc-type piezoelectric transformer is used to obtain high voltage output for driving the ultrasonic motor. The piezoelectric transformer is operated in the radial vibration mode at resonance frequency close to the resonance frequency of the ultrasonic motor. Later, it was found that the piezoelectric transformer could drive the ultrasonic motor, even if their resonance frequencies are not exactly the same by incorporating the matching network in the circuit. The maximum speed of the ultrasonic motor obtained by using this driving method is over 300 rpm. It is believed that the results of this study will have impact on the integration and miniaturization of the ultrasonic motor and its driving circuit. PMID:12403137

  6. Changes of the Electrical and Optical Character of Polyimide Films Due to Exposure to High Energy GEO-like Electrons and the Chemistry that Drives it

    NASA Astrophysics Data System (ADS)

    Hoffmann, R.; Cooper, R.; Ferguson, D.

    As a result of the interaction between the spacecraft and its operational environment, the constituent materials begin to change. These changes are determined by a combination of: chemical reactions, contamination, and energy deposition. They can range in severity from negligible to total loss of the material. Virtually all properties of the material, the mechanical, optical/thermal, and electrical are altered in largely unknown ways from the pristine materials. This negatively impacts the ability of spacecraft operators to predict the behavior of a spacecraft as it ages its environment. For example, in the case of electrical conduction in polyimide, there is a three orders of magnitude decrease in the resistivity after only eight months of simulated GEO electron exposure. Optical changes in the material also dramatically impact the ability of ground based optical observations to identify and track both known and unknown spacecraft. We will be presenting work done within the Spacecraft Charging and Instrument Calibration Lab at AFRL/RVB to quantify the changes in total reflection, BRDF, and electrical conduction of aluminized polyimide film after simulated aging in a GEO-like electron environment. We correlate these data with the chemical structure of the film as determined by XPS and NMR. A deeper, predictive understanding of how materials change will not only increase the operational lifetime of space assets by providing more accurate data to operators, it will improve SSA by allowing ground based observers to more accurately deduce component materials and determine how long a spacecraft has been in orbit.

  7. The detection of lubricating oil viscosity changes in gearbox transmission systems driven by sensorless variable speed drives using electrical supply parameters

    NASA Astrophysics Data System (ADS)

    Abusaad, S.; Brethee, K.; Assaeh, M.; Zhang, R.; Gu, F.; Ball, A. D.

    2015-07-01

    Lubrication oil plays a decisive role to maintain a reliable and efficient operation of gear transmissions. Many offline methods have been developed to monitor the quality of lubricating oils. This work focus on developing a novel online method to diagnose oil degradation based on the measurements from power supply system to the gearbox. Experimental studies based on an 10kW industrial gearbox fed by a sensorless variable speed drive (VSD) shows that measurable changes in both static power and dynamic behaviour are different with lube oils tested. Therefore, it is feasible to use the static power feature to indicate viscosity changes at low and moderate operating speeds. In the meantime, the dynamic feature can separate viscosity changes for all different tested cases.

  8. AC/RF Superconductivity

    SciTech Connect

    Ciovati, Gianluigi

    2015-02-01

    This contribution provides a brief introduction to AC/RF superconductivity, with an emphasis on application to accelerators. The topics covered include the surface impedance of normal conductors and superconductors, the residual resistance, the field dependence of the surface resistance, and the superheating field.

  9. Rabi oscillations at different tunnel couplings for an ac-gated quantum dot qubit

    NASA Astrophysics Data System (ADS)

    Thorgrimsson, Brandur; Kim, Dohun; Simmons, C. B.; Ward, Daniel R.; Foote, Ryan H.; Savage, D. E.; Lagally, M. G.; Friesen, Mark; Coppersmith, S. N.; Eriksson, M. A.

    2015-03-01

    One way to create a qubit is to use two distinct positions of a single electron as qubit states. Such a system can be achieved by using the left and right positions in a gated double quantum dot. In this system the qubit is strongly coupled to electric fields and has potential for high-speed operations. By tuning specific gate voltages, the tunnel coupling between the left and right quantum dots can be changed. Here, by using resonant ac microwave driving and gate tuning, we explore variations of T2* and the Rabi frequency on the tunnel coupling and microwave drive power, and we study strong driving effects such as generation of second harmonics. This work was supported in part by ARO (W911NF-12-0607) and NSF (DMR-1206915 and PHY-1104660). Development and maintenance of the growth facilities used for fabricating samples is sup- ported by DOE (DE-FG02-03ER46028). This research utilized NSF-supported shared facilities at the University of Wisconsin-Madison.

  10. Powertrain system for a hybrid electric vehicle

    DOEpatents

    Reed, R.G. Jr.; Boberg, E.S.; Lawrie, R.E.; Castaing, F.J.

    1999-08-31

    A hybrid electric powertrain system is provided including an electric motor/generator drivingly engaged with the drive shaft of a transmission. The electric is utilized for synchronizing the rotation of the drive shaft with the driven shaft during gear shift operations. In addition, a mild hybrid concept is provided which utilizes a smaller electric motor than typical hybrid powertrain systems. Because the electric motor is drivingly engaged with the drive shaft of the transmission, the electric motor/generator is driven at high speed even when the vehicle speed is low so that the electric motor/generator provides more efficient regeneration. 34 figs.

  11. Powertrain system for a hybrid electric vehicle

    DOEpatents

    Reed, Jr., Richard G.; Boberg, Evan S.; Lawrie, Robert E.; Castaing, Francois J.

    1999-08-31

    A hybrid electric powertrain system is provided including an electric motor/generator drivingly engaged with the drive shaft of a transmission. The electric is utilized for synchronizing the rotation of the drive shaft with the driven shaft during gear shift operations. In addition, a mild hybrid concept is provided which utilizes a smaller electric motor than typical hybrid powertrain systems. Because the electric motor is drivingly engaged with the drive shaft of the transmission, the electric motor/generator is driven at high speed even when the vehicle speed is low so that the electric motor/generator provides more efficient regeneration.

  12. Electrohydrodynamics of Charge Separation in Droplet-Based Ion Sources with Time-Varying Electrical and Mechanical Actuation

    PubMed Central

    Forbes, Thomas P.; Degertekin, F. Levent; Fedorov, Andrei G.

    2010-01-01

    Charge transport and separation in mechanically-driven, droplet-based ion sources are investigated using computational analysis and supporting experiments. A first-principles model of electrohydrodynamics (EHD) and charge migration is formulated and implemented using FLUENT CFD software for jet/droplet formation. For validation, classical experiments of electrospraying from a thin capillary are simulated, specifically, the transient EHD cone-jet formation of a fluid with finite electrical conductivity, and the Taylor cone formation in a perfectly electrically-conducting fluid. The model is also used to investigate the microscopic physics of droplet charging in mechanically-driven droplet-based ion sources, such as AMUSE (Array of Micromachined UltraSonic Electrospray). Here, AMUSE is subject to DC and AC electric fields of varying amplitude and phase, with respect to a time-varying mechanical force driving the droplet formation. For the DC-charging case, a linear relationship is demonstrated between the charge carried by each droplet and an applied electric field magnitude, in agreement with previously reported experiments. For the AC-charging case, a judiciously-chosen phase-shift in the time-varying mechanical (driving ejection) and electrical (driving charge transport) signals allows for a significantly increased amount of charge, of desired polarity, to be pumped into a droplet upon ejection. Complementary experimental measurements of electrospray electrical current and charge-per-droplet, produced by the AMUSE ion source, are performed and support theoretical predictions for both DC and AC-charging cases. The theoretical model and simulation tools provide a versatile and general analytical framework for fundamental investigations of coupled electrohydrodynamics and charge transport. The model also allows for the exploration of different configurations and operating modes to optimize charge separation in atmospheric pressure electrohydrodynamic ion sources

  13. Development of a dynamometer for an integrated-starter-generator (ISG) motor used in electric vehicles

    NASA Astrophysics Data System (ADS)

    Wang, Zai-zhou; Zhang, Cheng-ning; Song, Qiang; Zhang, Chun-xiang

    2008-12-01

    Hybrid-Electric Vehicle (HEV) which combined the electric motor with auxiliary power unit in a car driven is introduced. Characteristic of Hybrid-Electric Vehicle are different from the other vehicle, in the structure of Hybrid-Electric Vehicle, Integrated Starter Generator (ISG) electrical system can achieve high efficient performance of driving and generating electricity simultaneously. These systems adopt the sum torque through engine and generator, the motor connected transmission through engine. According to the requirements of different conditions, the torque of motor and transmission are compound in various forms to achieve optimal driving efficiency.This study developed a dynamometer to measure the relationship between locked torques with temperature rises of an Integrated Starter Generator motor used in electrical vehicles. The dynamometer adopted an AC motor to obtain the relationship between drive and load functions, which developed in this study can perform real-time measurements and storage of measured data obtained from the dynamometer. Experiments for measuring temperature rise of ISG motor were performed at three different conditions, namely 56 Nm locked rotor torques and 18.8A locked rotor current; 57.1Nm constant torque at 1050rpm; constant power with 14.3Nm and 4050rpm, respectively. Based on the theory of temperature rise, the temperature rises of motor are 14K, 33.1K, and 16.01K for the tested cases respectively. Measured results show that the performance of motor system is satisfied with the design.

  14. Fuzzy efficiency optimization of AC induction motors

    NASA Technical Reports Server (NTRS)

    Jani, Yashvant; Sousa, Gilberto; Turner, Wayne; Spiegel, Ron; Chappell, Jeff

    1993-01-01

    This paper describes the early states of work to implement a fuzzy logic controller to optimize the efficiency of AC induction motor/adjustable speed drive (ASD) systems running at less than optimal speed and torque conditions. In this paper, the process by which the membership functions of the controller were tuned is discussed and a controller which operates on frequency as well as voltage is proposed. The membership functions for this dual-variable controller are sketched. Additional topics include an approach for fuzzy logic to motor current control which can be used with vector-controlled drives. Incorporation of a fuzzy controller as an application-specific integrated circuit (ASIC) microchip is planned.

  15. Electron Locking in Current Drive

    NASA Astrophysics Data System (ADS)

    McCollam, K. J.; Jarboe, T. R.; Nelson, B. A.; Orvis, D. J.; Raman, R.; Redd, A. J.; Smith, R. J.; Nagata, M.; Uyama, T.

    2000-10-01

    The traveling n=1, m~= q_edge magnetic distortion observed in the Helicity Injected Torus (HIT-II) during coaxial helicity injection (CHI) is responsible for some current profile relaxation. A model for electromotive current drive, called the electron locking model, can account for the results of current drive experiments in both the HIT-II and the original HIT devices. The most relevant of these results involve the the frequencies and directions of the mode itself, the E× B drift, and the electric current drift. In spherical tokamaks with CHI, electrode and coil polarities can be changed to control the relative directions of these drifts. Results from HIT-II experiments with different polarities are shown. These point out the character n=1, m~= q_edge mode, and suggest its role in CHI current drive. The electron locking model is presented, and is also discussed in the context of mean field electrodynamics. This model might also be applied to other types of current drive, such as rotating magnetic field (RMF) current drive, oscillating field current drive (OFCD), steady inductive helicity injection (SIHI), or Ohmic current drive in a reversed field pinch (RFP). These examples are discussed.

  16. Perceived Danger while Intoxicated Uniquely Contributes to Driving after Drinking

    PubMed Central

    Morris, David H.; Treloar, Hayley R.; Niculete, Maria E.; McCarthy, Denis M.

    2013-01-01

    Background Previous findings suggest that alcohol alters perceptions of risky behaviors such as drinking and driving. However, studies testing these perceptions as a predictor of drinking and driving typically measure these perceptions while participants are sober. The present study tested whether the perceived danger of driving after drinking assessed while intoxicated was associated with increased willingness to drive and self-reported drinking-and-driving behavior over and above perceptions assessed while sober. Additionally, we tested the effect of acute tolerance on the perceived danger of driving after drinking assessed on the ascending and descending limbs of the breath alcohol concentration (BrAC) curve. Methods Eighty-two young adults attended two counterbalanced laboratory sessions. In one session, participants consumed a moderate dose of alcohol (men: .72 g/kg, women: .65 g/kg) and reported the perceived danger of driving and their willingness to drive at multiple points across the BrAC curve. On a separate occasion, participants remained sober and appraised the dangerousness of driving at a hypothetical, illegal BrAC. Results Perceptions of the dangerousness of driving following alcohol administration were associated with increased willingness to drive and higher rates of self-reported drinking-and-driving behavior over and above perceptions reported when sober. Furthermore, perceived danger was reduced on the descending limb of the BrAC curve, compared to the ascending limb, suggesting the occurrence of acute tolerance. Conclusions Results from this study suggest that intoxicated perceptions are uniquely associated with drinking-and-driving decisions and that the perceived danger of drinking and driving is lower on the descending limb of the BrAC curve. Efforts to prevent alcohol-impaired driving have focused on increasing awareness of the danger of driving after drinking. Prevention efforts may be enhanced by educating drivers about how intoxication

  17. AC power systems handbook

    SciTech Connect

    Whitaker, J.

    1991-01-01

    Transient disturbances are what headaches are made of. Whatever you call them-spikes, surges, are power bumps-they can take your equipment down and leave you with a complicated and expensive repair job. Protection against transient disturbances is a science that demands attention to detail. This book explains how the power distribution system works, what can go wrong with it, and how to protect a facility against abnormalities. system grounding and shielding are covered in detail. Each major method of transient protection is analyzed and its relative merits discussed. The book provides a complete look at the critical elements of the ac power system. Provides a complete look at the ac power system from generation to consumption. Discusses the mechanisms that produce transient disturbances and how to protect against them. Presents diagrams to facilitate system design. Covers new areas, such as the extent of the transient disturbance problem, transient protection options, and stand-by power systems.

  18. Increased Ac excision (iae): Arabidopsis thaliana mutations affecting Ac transposition.

    PubMed

    Jarvis, P; Belzile, F; Page, T; Dean, C

    1997-05-01

    The maize transposable element Ac is highly active in the heterologous hosts tobacco and tomato, but shows very much reduced levels of activity in Arabidopsis. A mutagenesis experiment was undertaken with the aim of identifying Arabidopsis host factors responsible for the observed low levels of Ac activity. Seed from a line carrying a single copy of the Ac element inserted into the streptomycin phosphotransferase (SPT) reporter fusion, and which displayed typically low levels of Ac activity, were mutagenized using gamma rays. Nineteen mutants displaying high levels of somatic Ac activity, as judged by their highly variegated phenotypes, were isolated after screening the M2 generation on streptomycin-containing medium. The mutations fall into two complementation groups, iae1 and iae2, are unlinked to the SPT::Ac locus and segregate in a Mendelian fashion. The iae1 mutation is recessive and the iae2 mutation is semi-dominant. The iae1 and iae2 mutants show 550- and 70-fold increases, respectively, in the average number of Ac excision sectors per cotyledon. The IAE1 locus maps to chromosome 2, whereas the SPT::Ac reporter maps to chromosome 3. A molecular study of Ac activity in the iae1 mutant confirmed the very high levels of Ac excision predicted using the phenotypic assay, but revealed only low levels of Ac re-insertion. Analyses of germinal transposition in the iae1 mutant demonstrated an average germinal excision frequency of 3% and a frequency of independent Ac re-insertions following germinal excision of 22%. The iae mutants represents a possible means of improving the efficiency of Ac/Ds transposon tagging systems in Arabidopsis, and will enable the dissection of host involvement in Ac transposition and the mechanisms employed for controlling transposable element activity.

  19. Cooling of high power generators and motors for electric propulsion

    NASA Astrophysics Data System (ADS)

    Szatkowski, J. L.

    1984-03-01

    This study reviews the history and development of marine electric propulsion drives, the types of electric propulsion, and the inherent losses which occur within the synchronous ac machines typically used for high-power propulsion systems. A thorough review of the literature pertaining to heat transfer in electrical machinery is made. In particular, the use of liquid cooling in various flow configurations, including buoyancy-driven thermosyphons and two-phase thermosyphons is analyzed. Forced-liquid cooling is feasible, but the required rotating seals are a problem in reliability. Closed-loop thermosyphon cooling appears feasible at high rotational speeds, although a secondary heat exchange through the shaft is required. Closed, two-phase thermosyphons and heat pipes are also feasible, but require forced-air circulation for heat rejection to the ambient. Since all of these concepts deserve additional attention, areas for further research and development are recommended.

  20. Perceptions of breath alcohol concentration (BrAC) levels among a sample of bar patrons with BrAC values of 0.08% or higher.

    PubMed

    Martin, Ryan J; Chaney, Beth H; Cremeens-Matthews, Jennifer; Vail-Smith, Karen

    2016-09-01

    Breath alcohol concentration (BrAC) is a commonly used measure of alcohol intoxication. Because of the potential negative consequences of excessive alcohol consumption, it is important to examine how accurately intoxicated individuals can estimate their BrAC values, especially individuals over the legal BrAC driving threshold (i.e., 0.08%). To better understand perceptions of BrAC values among intoxicated individuals, this field study examined actual BrAC values and BrAC range estimates (0.08% and above, 0.02-0.07%, less than 0.02%) among a sample of bar patrons (N = 454) with BrAC levels at 0.08% or higher. Bivariate and multivariate analyses were conducted to examine the relationship between actual BrAC values and perceived BrAC levels. We also examined whether the following demographic and drinking variables were associated with underestimating BrAC in this sample: gender, age, race, college student status, plans to get home, and hazardous drinking. Results indicated that the majority (60.4%) of participants underestimated their BrAC (i.e., less than 0.08%) and lower BrAC values correlated with underestimating BrAC ranges (p < .001, 95% CI[0.2, 0.6]). Further, females (p = .001, 95% CI[1.3, 3.3]) and participants under 21 (p = .039, 95% CI = 1.0, 2.6) were significantly more likely to estimate their BrAC to be less than 0.08%, which is concerning given that young (less than 21) intoxicated females are a group at high risk for sexual assault on college campuses. (PsycINFO Database Record PMID:27631614

  1. Introducing AC inductive reactance with a power tool

    NASA Astrophysics Data System (ADS)

    Bryant, Wesley; Baker, Blane

    2016-09-01

    The concept of reactance in AC electrical circuits is often non-intuitive and difficult for students to grasp. In order to address this lack of conceptual understanding, classroom exercises compare the predicted resistance of a power tool, based on electrical specifications, to measured resistance. Once students discover that measured resistance is smaller than expected, they are asked to explain these observations using previously studied principles of magnetic induction. Exercises also introduce the notion of inductive reactance and impedance in AC circuits and, ultimately, determine self-inductance of the motor windings within the power tool.

  2. Integration of regenerative shock absorber into vehicle electric system

    NASA Astrophysics Data System (ADS)

    Zhang, Chongxiao; Li, Peng; Xing, Shaoxu; Kim, Junyoung; Yu, Liangyao; Zuo, Lei

    2014-03-01

    Regenerative/Energy harvesting shock absorbers have a great potential to increase fuel efficiency and provide suspension damping simultaneously. In recent years there's intensive work on this topic, but most researches focus on electricity extraction from vibration and harvesting efficiency improvement. The integration of electricity generated from regenerative shock absorbers into vehicle electric system, which is very important to realize the fuel efficiency benefit, has not been investigated. This paper is to study and demonstrate the integration of regenerative shock absorber with vehicle alternator, battery and in-vehicle electrical load together. In the presented system, the shock absorber is excited by a shaker and it converts kinetic energy into electricity. The harvested electricity flows into a DC/DC converter which realizes two functions: controlling the shock absorber's damping and regulating the output voltage. The damping is tuned by controlling shock absorber's output current, which is also the input current of DC/DC converter. By adjusting the duty cycles of switches in the converter, its input impedance together with input current can be adjusted according to dynamic damping requirements. An automotive lead-acid battery is charged by the DC/DC converter's output. To simulate the working condition of combustion engine, an AC motor is used to drive a truck alternator, which also charges the battery. Power resistors are used as battery's electrical load to simulate in-vehicle electrical devices. Experimental results show that the proposed integration strategy can effectively utilize the harvested electricity and power consumption of the AC motor is decreased accordingly. This proves the combustion engine's load reduction and fuel efficiency improvement.

  3. DOE Hybrid and Electric Vehicle Test Platform

    SciTech Connect

    Gao, Yimin

    2012-03-31

    , and then generates motor torque command (traction or braking) to the motor controller based on the control algorithm software embedded in the vehicle controller ECU. The vehicle controller ECU is a re-programmable electronic control unit. Any control algorithm software developed can be easily downloaded to vehicle controller ECU to test any newly developed control strategy. The flexibility of the control system significantly enhances the practical applicability of the LabRAT. A new test methodology has been developed for the LabRAT simulating any vehicles running on road with different weights from compact passenger car to light duty truck on an AC or eddy current dynamometers without much effort for modification of the system. LabRAT is equipped with a fully functional data acquisition system supplied by CyberMetrix. The measurement points along the drive train are DC electric power between battery pack and motor controller input, AC electric power between motor controller and electric motor, mechanical power between motor and rear axle. The data acquisition system is designed with more capability than current requirements in order to meet the requirements for phase II.

  4. Interplay between electron overheating and ac Josephson effect

    NASA Astrophysics Data System (ADS)

    De Cecco, A.; Le Calvez, K.; Sacépé, B.; Winkelmann, C. B.; Courtois, H.

    2016-05-01

    We study the response of high-critical-current proximity Josephson junctions to a microwave excitation. Electron overheating in such devices is known to create hysteretic dc voltage-current characteristics. Here we demonstrate that it also strongly influences the ac response. The interplay of electron overheating and ac Josephson dynamics is revealed by the evolution of the Shapiro steps with the microwave drive amplitude. Extending the resistively shunted Josephson junction model by including a thermal balance for the electronic bath coupled to phonons, a strong electron overheating is obtained.

  5. Dynamic model tracking design for low inertia, high speed permanent magnet ac motors.

    PubMed

    Stewart, P; Kadirkamanathan, V

    2004-01-01

    Permanent magnet ac (PMAC) motors have existed in various configurations for many years. The advent of rare-earth magnets and their associated highly elevated levels of magnetic flux makes the permanent magnet motor attractive for many high performance applications from computer disk drives to all electric racing cars. The use of batteries as a prime storage element carries a cost penalty in terms of the unladen weight of the vehicle. Minimizing this cost function requires the minimum electric motor size and weight to be specified, while still retaining acceptable levels of output torque. This tradeoff can be achieved by applying a technique known as flux weakening which will be investigated in this paper. The technique allows the speed range of a PMAC motor to be greatly increased, giving a constant power range of more than 4:1. A dynamic model reference controller is presented which has advantages in ease of implementation, and is particularly suited to dynamic low inertia applications such as clutchless gear changing in high performance electric vehicles. The benefits of this approach are to maximize the torque speed envelope of the motor, particularly advantageous when considering low inertia operation. The controller is examined experimentally, confirming the predicted performance.

  6. Safe driving for teens

    MedlinePlus

    Driving and teenagers; Teens and safe driving; Automobile safety - teenage drivers ... Make a Commitment to Safety Teens also need to commit to being safe and responsible drivers in order to improve the odds in their favor. Reckless driving ...

  7. High-Frequency ac Power-Distribution System

    NASA Technical Reports Server (NTRS)

    Hansen, Irving G.; Mildice, James

    1987-01-01

    Loads managed automatically under cycle-by-cycle control. 440-V rms, 20-kHz ac power system developed. System flexible, versatile, and "transparent" to user equipment, while maintaining high efficiency and low weight. Electrical source, from dc to 2,200-Hz ac converted to 440-V rms, 20-kHz, single-phase ac. Power distributed through low-inductance cables. Output power either dc or variable ac. Energy transferred per cycle reduced by factor of 50. Number of parts reduced by factor of about 5 and power loss reduced by two-thirds. Factors result in increased reliability and reduced costs. Used in any power-distribution system requiring high efficiency, high reliability, low weight, and flexibility to handle variety of sources and loads.

  8. Effect of ac on current-induced domain wall motion

    NASA Astrophysics Data System (ADS)

    Kim, W. J.; Lee, T. D.; Choa, S. H.; Seo, S. M.; Lee, K. J.

    2007-05-01

    Saitoh et al. [Nature (London) 432, 203 (2004)] have reported the experimental result showing the interplay of a transverse domain wall with an electrical ac of megahertz-range frequencies. They observed a single peak of resistance in the frequency range and interpreted it with a nonadiabatic spin torque. It was argued that an ac current can induce a micrometer-range displacement of domain wall. We reconstructed the experiment in micromagnetic simulations considering the local nonzero nonadiabatic spin torque. We could not observe either an explicit single peak in the frequency-dependent resistance or an eventual displacement of domain wall by use of an ac. It indicates the local nonadiabatic torque is inappropriate to explain the experimental results of ac-induced domain wall motion. Other approaches such as the nonlocal nonadiabatic spin torque may be needed.

  9. Development of a 10 kW High Temperature High Power Density Three-Phase AC-DC-AC SiC Converter

    SciTech Connect

    Ning, Puqi

    2012-01-01

    This paper presents the development and experimental performance of a 10 kW, all SiC, 250 C junction temperature high-power-density three-phase ac-dc-ac converter. The electromagnetic interference filter, thermal system, high temperature package, and gate drive design are discussed in detail. Finally, tests confirming the feasibility and validating the theoretical basis of the prototype converter system are described.

  10. Boost Converters for Gas Electric and Fuel Cell Hybrid Electric Vehicles

    SciTech Connect

    McKeever, JW

    2005-06-16

    Hybrid electric vehicles (HEVs) are driven by at least two prime energy sources, such as an internal combustion engine (ICE) and propulsion battery. For a series HEV configuration, the ICE drives only a generator, which maintains the state-of-charge (SOC) of propulsion and accessory batteries and drives the electric traction motor. For a parallel HEV configuration, the ICE is mechanically connected to directly drive the wheels as well as the generator, which likewise maintains the SOC of propulsion and accessory batteries and drives the electric traction motor. Today the prime energy source is an ICE; tomorrow it will very likely be a fuel cell (FC). Use of the FC eliminates a direct drive capability accentuating the importance of the battery charge and discharge systems. In both systems, the electric traction motor may use the voltage directly from the batteries or from a boost converter that raises the voltage. If low battery voltage is used directly, some special control circuitry, such as dual mode inverter control (DMIC) which adds a small cost, is necessary to drive the electric motor above base speed. If high voltage is chosen for more efficient motor operation or for high speed operation, the propulsion battery voltage must be raised, which would require some type of two-quadrant bidirectional chopper with an additional cost. Two common direct current (dc)-to-dc converters are: (1) the transformer-based boost or buck converter, which inverts a dc voltage, feeds the resulting alternating current (ac) into a transformer to raise or lower the voltage, and rectifies it to complete the conversion; and (2) the inductor-based switch mode boost or buck converter [1]. The switch-mode boost and buck features are discussed in this report as they operate in a bi-directional chopper. A benefit of the transformer-based boost converter is that it isolates the high voltage from the low voltage. Usually the transformer is large, further increasing the cost. A useful feature

  11. Development of an AC Module System: Final Technical Report

    SciTech Connect

    Suparna Kadam; Miles Russell

    2012-06-15

    The GreenRay Inc. program focused on simplifying solar electricity and making it affordable and accessible to the mainstream population. This was accomplished by integrating a solar module, micro-inverter, mounting and monitoring into a reliable, 'plug and play' AC system for residential rooftops, offering the following advantages: (1) Reduced Cost: Reduction in installation labor with fewer components, faster mounting, faster wiring. (2) Maximized Energy Production: Each AC Module operates at its maximum, reducing overall losses from shading, mismatch, or module downtime. (3) Increased Safety. Electrical and fire safety experts agree that AC Modules have significant benefits, with no energized wiring or live connections during installation, maintenance or emergency conditions. (4) Simplified PV for a Broader Group of Installers. Dramatic simplification of design and installation of a solar power system, enabling faster and more efficient delivery of the product into the market through well-established, mainstream channels. This makes solar more accessible to the public. (5) Broadened the Rooftop Market: AC Modules enable solar for many homes that have shading, split roofs, or obstructions. In addition, due to the smaller building block size of 200W vs. 1000W, homeowners with budget limitations can start small and add to their systems over time. Through this DOE program GreenRay developed the all-in-one AC Module system with an integrated PV Module and microinverter, custom residential mounting and performance monitoring. Development efforts took the product from its initial concept, through prototypes, to a commercial product sold and deployed in the residential market. This pilot deployment has demonstrated the technical effectiveness of the AC Module system in meeting the needs and solving the problems of the residential market. While more expensive than the traditional central inverter systems at the pilot scale, the economics of AC Modules become more and more

  12. Identification of /sup 233/Ac

    SciTech Connect

    Chu, Y.Y.; Zhou, M.L.

    1983-09-01

    We report in this paper identification of the new isotope /sup 233/Ac. Uranium targets were irradiated with 28 GeV protons; after rapid retrieval of the target and separation of actinium from thorium, /sup 233/Ac was allowed to decay into the known /sup 233/Th daughter. Exhaustive chemical purification was employed to permit the identification of /sup 233/Th via its characteristic ..gamma.. radiations. The half-life derived for /sup 233/Ac from several experiments is 2.3 +- 0.3 min. The production cross section for /sup 233/Ac is 100 ..mu..b.

  13. AC and DC power transmission

    SciTech Connect

    Not Available

    1985-01-01

    The technical and economic assessment of AC and DC transmission systems; long distance transmission, cable transmission, system inter-connection, voltage support, reactive compensation, stabilisation of systems; parallel operation of DC links with AC systems; comparison between alternatives for particular schemes. Design and application equipment: design, testing and application of equipment for HVDC, series and shunt static compensated AC schemes, including associated controls. Installations: overall design of stations and conductor arrangements for HVDC, series and shunt static AC schemes including insulation co-ordination. System analysis and modelling.

  14. OAK RIDGE NATIONAL LABORATORY SPALLATION NEUTRON SOURCE ELECTRICAL SYSTEMS AVAILABILITY AND IMPROVEMENTS

    SciTech Connect

    Cutler, Roy I; Peplov, Vladimir V; Wezensky, Mark W; Norris, Kevin Paul; Barnett, William E; Hicks, Jim; Weaver, Joey T; Moss, John; Rust, Kenneth R; Mize, Jeffery J; Anderson, David E

    2011-01-01

    SNS electrical systems have been operational for 4 years. System availability statistics and improvements are presented for AC electrical systems, DC and pulsed power supplies and klystron modulators.

  15. A Computer Model for Teaching the Dynamic Behavior of AC Contactors

    ERIC Educational Resources Information Center

    Ruiz, J.-R. R.; Espinosa, A. G.; Romeral, L.

    2010-01-01

    Ac-powered contactors are extensively used in industry in applications such as automatic electrical devices, motor starters, and heaters. In this work, a practical session that allows students to model and simulate the dynamic behavior of ac-powered electromechanical contactors is presented. Simulation is carried out using a rigorous parametric…

  16. Recovery of consciousness in broilers following combined dc and ac stunning

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Broilers in the United States are typically electrically stunned using low voltage-high frequency pulsed DC water bath stunners and in the European Union broilers are electrocuted using high voltage-low frequency AC. DC stunned broilers regain consciousness in the absence of exsanguination and AC st...

  17. Cooling Floor AC Systems

    NASA Astrophysics Data System (ADS)

    Jun, Lu; Hao, Ding; Hong, Zhang; Ce, Gao Dian

    The present HVAC equipments for the residential buildings in the Hot-summer-and-Cold-winter climate region are still at a high energy consuming level. So that the high efficiency HVAC system is an urgently need for achieving the preset government energy saving goal. With its advantage of highly sanitary, highly comfortable and uniform of temperature field, the hot-water resource floor radiation heating system has been widely accepted. This paper has put forward a new way in air-conditioning, which combines the fresh-air supply unit and such floor radiation system for the dehumidification and cooling in summer or heating in winter. By analyze its advantages and limitations, we found that this so called Cooling/ Heating Floor AC System can improve the IAQ of residential building while keep high efficiency quality. We also recommend a methodology for the HVAC system designing, which will ensure the reduction of energy cost of users.

  18. High-power ac/dc variable load simulator

    NASA Technical Reports Server (NTRS)

    Joncas, K. P.; Birnbach, S.; Bruce, L. D.; Smith, L.

    1975-01-01

    Design of medium-power dynamic electrical load simulator has been extended to permit simulation of ac as well as dc loads and to provide for operation at higher power levels. Simulator is internally protected against reverse voltage, overvoltage, overcurrent, and overload conditions.

  19. Extended Driving Impairs Nocturnal Driving Performances

    PubMed Central

    Sagaspe, Patricia; Taillard, Jacques; Åkerstedt, Torbjorn; Bayon, Virginie; Espié, Stéphane; Chaumet, Guillaume; Bioulac, Bernard; Philip, Pierre

    2008-01-01

    Though fatigue and sleepiness at the wheel are well-known risk factors for traffic accidents, many drivers combine extended driving and sleep deprivation. Fatigue-related accidents occur mainly at night but there is no experimental data available to determine if the duration of prior driving affects driving performance at night. Participants drove in 3 nocturnal driving sessions (3–5am, 1–5am and 9pm–5am) on open highway. Fourteen young healthy men (mean age [±SD] = 23.4 [±1.7] years) participated Inappropriate line crossings (ILC) in the last hour of driving of each session, sleep variables, self-perceived fatigue and sleepiness were measured. Compared to the short (3–5am) driving session, the incidence rate ratio of inappropriate line crossings increased by 2.6 (95% CI, 1.1 to 6.0; P<.05) for the intermediate (1–5am) driving session and by 4.0 (CI, 1.7 to 9.4; P<.001) for the long (9pm–5am) driving session. Compared to the reference session (9–10pm), the incidence rate ratio of inappropriate line crossings were 6.0 (95% CI, 2.3 to 15.5; P<.001), 15.4 (CI, 4.6 to 51.5; P<.001) and 24.3 (CI, 7.4 to 79.5; P<.001), respectively, for the three different durations of driving. Self-rated fatigue and sleepiness scores were both positively correlated to driving impairment in the intermediate and long duration sessions (P<.05) and increased significantly during the nocturnal driving sessions compared to the reference session (P<.01). At night, extended driving impairs driving performances and therefore should be limited. PMID:18941525

  20. AC current rectification in Nb films with or without symmetrical Nb/Ni periodic pinning arrays in perpendicular magnetic field

    NASA Astrophysics Data System (ADS)

    Pryadun, Vladimir

    2005-03-01

    Rectification of AC current has been observed in plain superconducting Nb films and in Nb/Ni films with symmetric periodic pinning centers. The rectified DC voltage appears for various sample geometries (cross or strip) both along and transverse to the alternating current direction, is nearly anti-symmetric with perpendicular magnetic field and strongly dependent on temperature below Tc. Analyses of the data at different temperatures, drive frequencies from 100kHz to 150MHz and at the different sample sides [1] shows that not far below Tc the rectification phenomena can be understood in terms of generation of electric fields due to local excess of critical current. Further below Tc anisotropic pinning effects could also contribute to the rectification. [1] F.G.Aliev, et al., Cond. Mat.405656. Supported by Comunidad Autonoma de Madrid -CAM/07N/0050/2002

  1. Vertical Electric Field Measurements with Copper Plates by Sounding Balloon

    NASA Astrophysics Data System (ADS)

    Wen, Shao-Chun; Chiu, Cheng-Hsiu; Bing-Chih Chen, Alfred; Hsu, Rue-Ron; Su, Han-Tzong

    2015-04-01

    The vertical electric field plays an important role in driving the circulation of the global electric circuit, and crucial to the formation of the transient luminous events (TLEs). The in-situ measurement of the electric field in the upper atmosphere, especially from cloud top to the bottom of the ionosphere is very challenging but essential. Limited by the flight vehicle, the measurements of the electric field in and above cloud, especiall thundercloud, is rare up to now. A light-weight electric field meter was developed independently and sent to 30 km height by small meteorological balloons successfully. Other than the existing long-spaced, spherical probe design, an improved electric field meter has been built and tested carefully. A new circuit with ultra high input impedance and a high voltage amplifier is implemented to reduce the AC noise induced by the voltage divider. Two copper plates are used to replace the double spherical probes which is spaced by a long fiberglass boom. The in-lab calibration and tests show that this new model is superior to the existing design and very sensitive to the variation of the DC electric field. In this poster, the design and the in-lab tests will be presented, and preliminary results of the flight experiments are also discussed.

  2. Coaxial Redundant Drives

    NASA Technical Reports Server (NTRS)

    Brissette, R.

    1983-01-01

    Harmonic drives allow redundancy and high out put torque in small package. If main drive fails, standby drive takes over and produces torque along same axis as main drive. Uses include power units in robot for internal pipeline inspection, manipulators in deep submersible probes or other applications in which redundancy protects against costly failures.

  3. Low cost, compact, and high efficiency traction motor for electric and hybrid electric vehicles

    SciTech Connect

    Ehsani, Mark

    2002-10-07

    A new motor drive, the switched reluctance motor drive, has been developed for hybrid-electric vehicles. The motor drive has been designed, built and tested in the test bed at a near vehicle scale. It has been shown that the switched reluctance motor drive is more suitable for traction application than any other motor drive.

  4. Driving segment simulation for determination of the most effective driving features for HEV intelligent control

    NASA Astrophysics Data System (ADS)

    Montazeri, Morteza; Fotouhi, Abbas; Naderpour, Akbar

    2012-02-01

    This paper presents a methodological approach for determination of the most effective driving features for hybrid electric vehicle intelligent control, using the driving segment simulation. In this approach, driving data gathering is first performed in real traffic conditions using Advanced Vehicle Locator systems. The vehicle's speed time series are then divided into small segments. Subsequently, 19 driving features are defined for each driving segment, and the influence of the driving features on the vehicle's fuel consumption (FC) and exhaust emissions is investigated, using driving the driving segment simulation. The simulation approach is also verified by experimental test. Finally, the driving features are ranked by a new approach based on the definition of an effectiveness index and a correlation analysis. The results demonstrate that the velocity-dependent driving features such as 'energy', 'mean of velocity', 'displacement' and 'maximum velocity' are more effective on vehicle's FC and exhaust emissions. However, because of high dependency between these features, this study suggests independent driving features among the most effective driving features.

  5. Trapping polar molecules in an ac trap

    SciTech Connect

    Bethlem, Hendrick L.; Veldhoven, Jacqueline van; Schnell, Melanie; Meijer, Gerard

    2006-12-15

    Polar molecules in high-field seeking states cannot be trapped in static traps as Maxwell's equations do not allow a maximum of the electric field in free space. It is possible to generate an electric field that has a saddle point by superposing an inhomogeneous electric field to an homogeneous electric field. In such a field, molecules are focused along one direction, while being defocused along the other. By reversing the direction of the inhomogeneous electric field the focusing and defocusing directions are reversed. When the fields are being switched back and forth at the appropriate rate, this leads to a net focusing force in all directions. We describe possible electrode geometries for creating the desired fields and discuss their merits. Trapping of {sup 15}ND{sub 3} ammonia molecules in a cylindrically symmetric ac trap is demonstrated. We present measurements of the spatial distribution of the trapped cloud as a function of the settings of the trap and compare these to both a simple model assuming a linear force and to full three-dimensional simulations of the experiment. With the optimal settings, molecules within a phase-space volume of 270 mm{sup 3} (m/s){sup 3} remain trapped. This corresponds to a trap depth of about 5 mK and a trap volume of about 20 mm{sup 3}.

  6. Solar array drive system

    NASA Technical Reports Server (NTRS)

    Berkopec, F. D.; Sturman, J. C.; Stanhouse, R. W.

    1976-01-01

    A solar array drive system consisting of a solar array drive mechanism and the corresponding solar array drive electronics is being developed. The principal feature of the solar array drive mechanism is its bidirectional capability which enables its use in mechanical redundancy. The solar array drive system is of a widely applicable design. This configuration will be tested to determine its acceptability for generic mission sets. Foremost of the testing to be performed is the testing for extended duration.

  7. Electric Drive Vehicle Deployment Act of 2011

    THOMAS, 112th Congress

    Rep. Biggert, Judy [R-IL-13

    2011-05-03

    05/13/2011 Referred to the Subcommittee on Technology, Information Policy, Intergovernmental Relations and Procurement Reform . (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  8. AC Loss Measurements on a 2G YBCO Coil

    SciTech Connect

    Rey, Christopher M; Duckworth, Robert C; Schwenterly, S W

    2011-01-01

    The Oak Ridge National Laboratory (ORNL) is collaborating with Waukesha Electric Systems (WES) to continue development of HTS power transformers. For compatibility with the existing power grid, a commercially viable HTS transformer will have to operate at high voltages in the range of 138 kV and above, and will have to withstand 550-kV impulse voltages as well. Second-generation (2G) YBCO coated conductors will be required for an economically-competitive design. In order to adequately size the refrigeration system for these transformers, the ac loss of these HTS coils must be characterized. Electrical AC loss measurements were conducted on a prototype high voltage (HV) coil with co-wound stainless steel at 60 Hz in a liquid nitrogen bath using a lock-in amplifier technique. The prototype HV coil consisted of 26 continuous (without splice) single pancake coils concentrically centered on a stainless steel former. For ac loss measurement purposes, voltage tap pairs were soldered across each set of two single pancake coils so that a total of 13 separate voltage measurements could be made across the entire length of the coil. AC loss measurements were taken as a function of ac excitation current. Results show that the loss is primarily concentrated at the ends of the coil where the operating fraction of critical current is the highest and show a distinct difference in current scaling of the losses between low current and high current regimes.

  9. DOE Fundamentals Handbook: Electrical Science, Volume 4

    SciTech Connect

    Not Available

    1992-06-01

    The Electrical Science Fundamentals Handbook was developed to assist nuclear facility operating contractors provide operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of electrical theory, terminology, and application. The handbook includes information on alternating current (AC) and direct current (DC) theory, circuits, motors, and generators; AC power and reactive transformers; and electrical test components; batteries; AC and DC voltage regulators; instruments and measuring devices. This information will provide personnel with a foundation for understanding the basic operation of various types of DOE nuclear facility electrical equipment.

  10. DOE Fundamentals Handbook: Electrical Science, Volume 1

    SciTech Connect

    Not Available

    1992-06-01

    The Electrical Science Fundamentals Handbook was developed to assist nuclear facility operating contractors provide operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of electrical theory, terminology, and application. The handbook includes information on alternating current (AC) and direct current (DC) theory, circuits, motors, and generators; AC power and reactive components; batteries; AC and DC voltage regulators; transformers; and electrical test instruments and measuring devices. This information will provide personnel with a foundation for understanding the basic operation of various types of DOE nuclear facility electrical equipment.

  11. AC electrophoretic deposition of organic-inorganic composite coatings.

    PubMed

    Yoshioka, T; Chávez-Valdez, A; Roether, J A; Schubert, D W; Boccaccini, A R

    2013-02-15

    Alternating current electrophoretic deposition (AC-EPD) of polyacrylic acid (PAA)-titanium oxide (TiO(2)) nanoparticle composites on stainless steel electrodes was investigated in basic aqueous solution. AC square wave with duty cycle of 80% was applied at a frequency of 1 kHz. FTIR-ATR spectra showed that both AC and direct current (DC) EPD successfully deposited PAA-TiO(2) composites. The deposition rate using AC-EPD was lower than that obtained in direct current DC-EPD. However, the microstructure and surface morphology of the deposited composite coatings were different depending on the type of electric field applied. AC-EPD applied for not more than 5 min led to smooth films without bubble formation, while DC-EPD for 1 min or more showed deposits with microstructural defects possibly as result of water electrolysis. AC-EPD was thus for the first time demonstrated to be a suitable technique to deposit organic-inorganic composite coatings from aqueous suspensions, showing that applying a square wave and frequency of 1 kHz leads to uniform PAA-TiO(2) composite coatings on conductive materials. PMID:23218240

  12. AC electrophoretic deposition of organic-inorganic composite coatings.

    PubMed

    Yoshioka, T; Chávez-Valdez, A; Roether, J A; Schubert, D W; Boccaccini, A R

    2013-02-15

    Alternating current electrophoretic deposition (AC-EPD) of polyacrylic acid (PAA)-titanium oxide (TiO(2)) nanoparticle composites on stainless steel electrodes was investigated in basic aqueous solution. AC square wave with duty cycle of 80% was applied at a frequency of 1 kHz. FTIR-ATR spectra showed that both AC and direct current (DC) EPD successfully deposited PAA-TiO(2) composites. The deposition rate using AC-EPD was lower than that obtained in direct current DC-EPD. However, the microstructure and surface morphology of the deposited composite coatings were different depending on the type of electric field applied. AC-EPD applied for not more than 5 min led to smooth films without bubble formation, while DC-EPD for 1 min or more showed deposits with microstructural defects possibly as result of water electrolysis. AC-EPD was thus for the first time demonstrated to be a suitable technique to deposit organic-inorganic composite coatings from aqueous suspensions, showing that applying a square wave and frequency of 1 kHz leads to uniform PAA-TiO(2) composite coatings on conductive materials.

  13. ACS CCD Stability Monitor

    NASA Astrophysics Data System (ADS)

    Grogin, Norman

    2012-10-01

    A moderately crowded stellar field in the cluster 47 Tuc {6 arcmin West of the cluster core} is observed every four months with the WFC. The first visit exercises the full suite of broad and narrow band imaging filters and sub-array modes; following visits observe with only the six most popular Cycle 18 filters in full-frame mode. The positions and magnitudes of objects will be used to monitor local and large scale variations in the plate scale and the sensitivity of the detectors and to derive an independent measure of the detector CTE. One exposure in each sub-array mode with the WFC will allow us to verify that photometry obtained in full-frame and in sub-array modes are repeatable to better than 1%. This test is important for the ACS Photometric Cross-Calibration program, which uses sub-array exposures. This program may receive additional orbits to investigate ORIENT-dependent geometric distortion, which motivates the ORIENT and BETWEEN requirement on the first visit.

  14. Effect of different breath alcohol concentrations on driving performance in horizontal curves.

    PubMed

    Zhang, Xingjian; Zhao, Xiaohua; Du, Hongji; Ma, Jianming; Rong, Jian

    2014-11-01

    Driving under the influence of alcohol on curved roadway segments has a higher risk than driving on straight segments. To explore the effect of different breath alcohol concentration (BrAC) levels on driving performance in roadway curves, a driving simulation experiment was designed to collect 25 participants' driving performance parameters (i.e., speed and lane position) under the influence of 4 BrAC levels (0.00%, 0.03%, 0.06% and 0.09%) on 6 types of roadway curves (3 radii×2 turning directions). Driving performance data for 22 participants were collected successfully. Then the average and standard deviation of the two parameters were analyzed, considering the entire curve and different sections of the curve, respectively. The results show that the speed throughout curves is higher when drinking and driving than during sober driving. The significant interaction between alcohol and radius exists in the middle and tangent segments after a curve exit, indicating that a small radius can reduce speed at high BrAC levels. The significant impairment of alcohol on the stability of speed occurs mainly in the curve section between the point of curve (PC) and point of tangent (PT), with no impairment noted in tangent sections. The stability of speed is significantly worsened at higher BrAC levels. Alcohol and radius have interactive effects on the standard deviation of speed in the entry segment of curves, indicating that the small radius amplifies the instability of speed at high BrAC levels. For lateral movement, drivers tend to travel on the right side of the lane when drinking and driving, mainly in the approach and middle segments of curves. Higher BrAC levels worsen the stability of lateral movement in every segment of the curve, regardless of its radius and turning direction. The results are expected to provide reference for detecting the drinking and driving state.

  15. Cannabis effects on driving longitudinal control with and without alcohol.

    PubMed

    Hartman, Rebecca L; Brown, Timothy L; Milavetz, Gary; Spurgin, Andrew; Pierce, Russell S; Gorelick, David A; Gaffney, Gary; Huestis, Marilyn A

    2016-11-01

    Although evidence suggests cannabis impairs driving, its driving-performance effects are not fully characterized. We aimed to establish cannabis' effects on driving longitudinal control (with and without alcohol, drivers' most common drug combination) relative to psychoactive ∆(9) -tetrahydrocannabinol (THC) blood concentrations. Current occasional (≥1×/last 3 months, ≤3 days per week) cannabis smokers drank placebo or low-dose alcohol, and inhaled 500 mg placebo, low (2.9%), or high (6.7%) THC vaporized cannabis over 10 min ad libitum in separate sessions (within-subject, six conditions). Participants drove (National Advanced Driving Simulator, University of Iowa) simulated drives 0.5-1.3 h post-inhalation. Blood and breath alcohol samples were collected before (0.17 and 0.42 h) and after (1.4 and 2.3 h) driving. We evaluated the mean speed (relative to limit), standard deviation (SD) of speed, percent time spent >10% above/below the speed limit (percent speed high/percent speed low), longitudinal acceleration, and ability to maintain headway relative to a lead vehicle (headway maintenance) against blood THC and breath alcohol concentrations (BrAC). In N=18 completing drivers, THC was associated with a decreased mean speed, increased percent speed low and increased mean following distance during headway maintenance. BrAC was associated with increased SD speed and increased percent speed high, whereas THC was not. Neither was associated with altered longitudinal acceleration. A less-than-additive THC*BrAC interaction was detected in percent speed high (considering only non-zero data and excluding an outlying drive event), suggesting cannabis mitigated drivers' tendency to drive faster with alcohol. Cannabis was associated with slower driving and greater headway, suggesting a possible awareness of impairment and attempt to compensate. Copyright © 2016 John Wiley & Sons, Ltd.

  16. Hybrid immersed interface-immersed boundary methods for AC dielectrophoresis

    SciTech Connect

    Hossan, Mohammad Robiul; Dillon, Robert; Dutta, Prashanta

    2014-08-01

    Dielectrophoresis, a nonlinear electrokinetic transport mechanism, has become popular in many engineering applications including manipulation, characterization and actuation of biomaterials, particles and biological cells. In this paper, we present a hybrid immersed interface–immersed boundary method to study AC dielectrophoresis where an algorithm is developed to solve the complex Poisson equation using a real variable formulation. An immersed interface method is employed to obtain the AC electric field in a fluid media with suspended particles and an immersed boundary method is used for the fluid equations and particle transport. The convergence of the proposed algorithm as well as validation of the hybrid scheme with experimental results is presented. In this paper, the Maxwell stress tensor is used to calculate the dielectrophoretic force acting on particles by considering the physical effect of particles in the computational domain. Thus, this study eliminates the approximations used in point dipole methods for calculating dielectrophoretic force. A comparative study between Maxwell stress tensor and point dipole methods for computing dielectrophoretic forces are presented. The hybrid method is used to investigate the physics of dielectrophoresis in microfluidic devices using an AC electric field. The numerical results show that with proper design and appropriate selection of applied potential and frequency, global electric field minima can be obtained to facilitate multiple particle trapping by exploiting the mechanism of negative dielectrophoresis. Our numerical results also show that electrically neutral particles form a chain parallel to the applied electric field irrespective of their initial orientation when an AC electric field is applied. This proposed hybrid numerical scheme will help to better understand dielectrophoresis and to design and optimize microfluidic devices.

  17. Path integral approach to Brownian motion driven with an ac force

    NASA Astrophysics Data System (ADS)

    Chen, L. Y.; Nash, P. L.

    2004-09-01

    Brownian motion in a periodic potential driven by an ac (oscillatory) force is investigated for the full range of damping constant from the overdamped limit to the underdamped limit. The path (functional) integral approach is advanced to produce formulas for the probability distribution function and for the current of the Brownian particle in response to an ac driving force. The negative friction Langevin dynamics technique is employed to evaluate the dc current for various parameters without invoking the overdamped or the underdamped approximation. The dc current is found to have nonlinear dependence upon the damping constant, the potential parameter, and the ac force magnitude and frequency.

  18. Magnetostrictive Roller-Drive Stepping Motor

    NASA Technical Reports Server (NTRS)

    Vranish, John M.

    1993-01-01

    Proposed motor based on magnetostrictive effect provides stepped angular motion with angular increments of order of 100 microradians. Driven to repeat stepping cycle rapidly enough to achieve maximum speed of about 20 rpm, provides torque an order of magnitude greater than electric motors, and brakes itself when power turned off. Magnetostrictive rods in electromagnet coils push against drive plate, causing it to rotate slightly. This slight rotation jams conical rollers between cam surfaces on outer drive ring and split drum, so rollers transmit rotation to drum. Suitable for precise, high-torque, fail-safe-braking, direct drive of robot joint, without bulk and weight of additional brake mechanism and gear train.

  19. Characterization and snubbing of a bidirectional MCT in a resonant ac link converter

    NASA Technical Reports Server (NTRS)

    Lee, Tony; Elbuluk, Malik E.; Zinger, Donald S.

    1993-01-01

    The MOS-Controlled Thyristor (MCT) is emerging as a powerful switch that combines the better characteristics of existing power devices. A study of switching stresses on an MCT switch under zero voltage resonant switching is presented. The MCT is used as a bidirectional switch in an ac/ac pulse density modulated inverter for induction motor drive. Current and voltage spikes are observed and analyzed with variations in the timing of the switching. Different snubber circuit configurations are under investigation to minimize the effect of these transients. The results will be extended to study and test the MCT switching in a medium power (5 hp) induction motor drive.

  20. Circuit for Driving Piezoelectric Transducers

    NASA Technical Reports Server (NTRS)

    Randall, David P.; Chapsky, Jacob

    2009-01-01

    The figure schematically depicts an oscillator circuit for driving a piezoelectric transducer to excite vibrations in a mechanical structure. The circuit was designed and built to satisfy application-specific requirements to drive a selected one of 16 such transducers at a regulated amplitude and frequency chosen to optimize the amount of work performed by the transducer and to compensate for both (1) temporal variations of the resonance frequency and damping time of each transducer and (2) initially unknown differences among the resonance frequencies and damping times of different transducers. In other words, the circuit is designed to adjust itself to optimize the performance of whichever transducer is selected at any given time. The basic design concept may be adaptable to other applications that involve the use of piezoelectric transducers in ultrasonic cleaners and other apparatuses in which high-frequency mechanical drives are utilized. This circuit includes three resistor-capacitor networks that, together with the selected piezoelectric transducer, constitute a band-pass filter having a peak response at a frequency of about 2 kHz, which is approximately the resonance frequency of the piezoelectric transducers. Gain for generating oscillations is provided by a power hybrid operational amplifier (U1). A junction field-effect transistor (Q1) in combination with a resistor (R4) is used as a voltage-variable resistor to control the magnitude of the oscillation. The voltage-variable resistor is part of a feedback control loop: Part of the output of the oscillator is rectified and filtered for use as a slow negative feedback to the gate of Q1 to keep the output amplitude constant. The response of this control loop is much slower than 2 kHz and, therefore, does not introduce significant distortion of the oscillator output, which is a fairly clean sine wave. The positive AC feedback needed to sustain oscillations is derived from sampling the current through the

  1. Driving and neurodegenerative diseases.

    PubMed

    Uc, Ergun Y; Rizzo, Matthew

    2008-09-01

    The proportion of elderly people in the general population is rising, resulting in greater numbers of drivers with neurodegenerative disorders such as Alzheimer's disease and Parkinson's disease. These neurodegenerative disorders impair cognition, visual perception, and motor function, leading to reduced driver fitness and greater crash risk. Yet neither medical diagnosis nor age alone is reliable enough to predict driver safety or crashes or to revoke the driving privileges of these individuals. Driving research utilizes tools such as questionnaires about driving habits and history, driving simulators, standardized road tests utilizing instrumented vehicles, and state driving records. Research challenges include outlining the evolution of driving safety, understanding the mechanisms of driving impairment, and developing a reliable and efficient standardized test battery for prediction of driver safety in neurodegenerative disorders. This information will enable healthcare providers to advise their patients with neurodegenerative disorders with more certainty, affect policy, and help develop rehabilitative measures for driving. PMID:18713573

  2. Dementia and driving

    MedlinePlus

    ... has dementia , deciding when they can no longer drive may be difficult. They may react in different ... that the person may not be able to drive safely, such as: Forgetting recent events Mood swings ...

  3. Gear bearing drive

    NASA Technical Reports Server (NTRS)

    Weinberg, Brian (Inventor); Mavroidis, Constantinos (Inventor); Vranish, John M. (Inventor)

    2011-01-01

    A gear bearing drive provides a compact mechanism that operates as an actuator providing torque and as a joint providing support. The drive includes a gear arrangement integrating an external rotor DC motor within a sun gear. Locking surfaces maintain the components of the drive in alignment and provide support for axial loads and moments. The gear bearing drive has a variety of applications, including as a joint in robotic arms and prosthetic limbs.

  4. Sequential Dependencies in Driving

    ERIC Educational Resources Information Center

    Doshi, Anup; Tran, Cuong; Wilder, Matthew H.; Mozer, Michael C.; Trivedi, Mohan M.

    2012-01-01

    The effect of recent experience on current behavior has been studied extensively in simple laboratory tasks. We explore the nature of sequential effects in the more naturalistic setting of automobile driving. Driving is a safety-critical task in which delayed response times may have severe consequences. Using a realistic driving simulator, we find…

  5. HVDC-AC system interaction from AC harmonics. Volume 1. Harmonic impedance calculations. Final report

    SciTech Connect

    Breuer, G D; Chow, J H; Lindh, C B; Miller, N W; Numrich, F H; Price, W W; Turner, A E; Whitney, R R

    1982-09-01

    Improved methods are needed to characterize ac system harmonic behavior for ac filter design for HVDC systems. The purpose of this General Electric Company RP1138 research is to evaluate the present filter design practice and to investigate methods for calculating system harmonic impedances. An overview of ac filter design for HVDC systems and a survey of literature related to filter design have been performed. Two methods for calculating system harmonic impedances have been investigated. In the measurement method, an instrumentation system for measuring system voltage and current has been assembled. Different schemes of using the measurements to calculate system harmonic impedances have been studied. In the analytical method, a procedure to include various operating conditions has been proposed. Computer programs for both methods have been prepared, and the results of the measurement and analytical methods analyzed. A conclusion of the project is that the measurement and analytical methods both provided reasonable results. There are correlations between the measured and analytical results for most harmonics, although there are discrepancies between the assumptions used in the two methods. A sensitivity approach has been proposed to further correlate the results. From the results of the analysis, it is recommended that both methods should be tested further. For the measurement method, more testing should be done to cover different system operating conditions. In the analytical method, more detailed models for representing system components should be studied. In addition, alternative statistical and sensitivity approaches should be attempted.

  6. Fluid cooled vehicle drive module

    DOEpatents

    Beihoff, Bruce C.; Radosevich, Lawrence D.; Meyer, Andreas A.; Gollhardt, Neil; Kannenberg, Daniel G.

    2005-11-15

    An electric vehicle drive includes a support may receive one or more power electronic circuits. The support may aid in removing heat from the circuits through fluid circulating through the support. The support, in conjunction with other packaging features may form a shield from both external EM/RFI and from interference generated by operation of the power electronic circuits. Features may be provided to permit and enhance connection of the circuitry to external circuitry, such as improved terminal configurations. Modular units may be assembled that may be coupled to electronic circuitry via plug-in arrangements or through interface with a backplane or similar mounting and interconnecting structures.

  7. Drill drive mechanism

    DOEpatents

    Dressel, Michael O.

    1979-01-01

    A drill drive mechanism is especially adapted to provide both rotational drive and axial feed for a drill of substantial diameter such as may be used for drilling holes for roof bolts in mine shafts. The drill shaft is made with a helical pattern of scroll-like projections on its surface for removal of cuttings. The drill drive mechanism includes a plurality of sprockets carrying two chains of drive links which are arranged to interlock around the drill shaft with each drive link having depressions which mate with the scroll-like projections. As the chain links move upwardly or downwardly the surfaces of the depressions in the links mate with the scroll projections to move the shaft axially. Tangs on the drive links mate with notch surfaces between scroll projections to provide a means for rotating the shaft. Projections on the drive links mate together at the center to hold the drive links tightly around the drill shaft. The entire chain drive mechanism is rotated around the drill shaft axis by means of a hydraulic motor and gear drive to cause rotation of the drill shaft. This gear drive also connects with a differential gearset which is interconnected with a second gear. A second motor is connected to the spider shaft of the differential gearset to produce differential movement (speeds) at the output gears of the differential gearset. This differential in speed is utilized to drive said second gear at a speed different from the speed of said gear drive, this speed differential being utilized to drive said sprockets for axial movement of said drill shaft.

  8. AC Electroosmotic Pumping in Nanofluidic Funnels.

    PubMed

    Kneller, Andrew R; Haywood, Daniel G; Jacobson, Stephen C

    2016-06-21

    We report efficient pumping of fluids through nanofluidic funnels when a symmetric AC waveform is applied. The asymmetric geometry of the nanofluidic funnel induces not only ion current rectification but also electroosmotic flow rectification. In the base-to-tip direction, the funnel exhibits a lower ion conductance and a higher electroosmotic flow velocity, whereas, in the tip-to-base direction, the funnel has a higher ion conductance and a lower electroosmotic flow velocity. Consequently, symmetric AC waveforms easily pump fluid through the nanofunnels over a range of frequencies, e.g., 5 Hz to 5 kHz. In our experiments, the nanofunnels were milled into glass substrates with a focused ion beam (FIB) instrument, and the funnel design had a constant 5° taper with aspect ratios (funnel tip width to funnel depth) of 0.1 to 1.0. We tracked ion current rectification by current-voltage (I-V) response and electroosmotic flow rectification by transport of a zwitterionic fluorescent probe. Rectification of ion current and electroosmotic flow increased with increasing electric field applied to the nanofunnel. Our results support three-dimensional simulations of ion transport and electroosmotic transport through nanofunnels, which suggest the asymmetric electroosmotic transport stems from an induced pressure at the junction of the nanochannel and nanofunnel tip. PMID:27230495

  9. DOE Fundamentals Handbook: Electrical Science, Volume 2

    SciTech Connect

    Not Available

    1992-06-01

    The Electrical Science Fundamentals Handbook was developed to assist nuclear facility operating contractors provide operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding terminology, and application. The handbook includes information on alternating current (AC) and direct current (DC) theory, circuits, motors, and generators; AC power and reactive components; batteries; AC and DC voltage regulators; transformers; and electrical test instruments and measuring devices. This information will provide personnel with a foundation for understanding the basic operation of various types of DOE nuclear facility electrical equipment.

  10. Dynamic modeling of lower hybrid current drive

    SciTech Connect

    Ignat, D.W.; Valeo, E.J.; Jardin, S.C.

    1993-10-01

    A computational model of lower hybrid current drive in the presence of an electric field is described and some results are given. Details of geometry, plasma profiles and circuit equations are treated carefully. Two-dimensional velocity space effects are approximated in a one-dimensional Fokker-Planck treatment.

  11. Wheelchair batteries: driving cycles and testing.

    PubMed

    Kauzlarich, J J; Ulrich, V; Bresler, M; Bruning, T

    1983-07-01

    The battery performance of electric wheelchairs was measured under indoor and outdoor conditions, and simulated driving cycles for these two environments were derived from these tests. Driving cycles were used to bench-test deep discharge wet cell and gel cell lead-acid batteries, nickel-cadmium batteries, and experimental nickel-zinc batteries. Results of this study support the conclusion that deep discharge wet cell lead-acid batteries satisfy wheelchair requirements and are the most economical choice. The effect of simulated wheelchair controller pulse width modulation on battery discharge compared to d.c. discharge was found to be negligible. A simple model analogous to Miner's Rule (3) plus results plotted on a Ragone chart of average power versus discharge time were found to correlate the effect of the highly variable actual power requirements of an electric wheelchair. Miner's Rule can predict battery performance for a given driving cycle.

  12. New drive system for large antennas

    NASA Astrophysics Data System (ADS)

    Bittner, G.; Boehmer, B.; Lange, W.; Maeder, H. F.; Rosenau, L.; Timmes, R.

    1982-07-01

    A new drive system for large antennas developed by Krupp is discussed, using the ECS test and observation station in Redu, Belgium as an example. The control concept is set forth, including a mechanical model of the antenna, the main structure of the control system, the system's electric current control, rotational speed control, and positional control. The hardware is discussed, including drive motors for elevation, azimuth, and polarization, tachoalternators, transistor amplifiers, servo control unit, polarization control unit, analog control unit, computer control unit, and computer interface. The electrical supply unit is described. The software is addressed, including communications and service functions via videoterminal, computerized time synchronization and remote control, antenna drive modes, satellite detection, and special features.

  13. AC operation and runaway electron behaviour in HT-7 tokamak

    NASA Astrophysics Data System (ADS)

    Lu, Hong-Wei; Hu, Li-Qun; Zhou, Rui-Jie; Lin, Shi-Yao; Zhong, Guo-Qiang; Wang, Shao-Feng; Chen, Kai-Yun; Xu, Ping; Zhang, Ji-Zong; Ling, Bi-Li; Mao, Song-Tao; Duan, Yan-Min

    2010-06-01

    Operation of HT-7 tokamak in a multicycle alternating square wave plasma current regime is reported. A set of AC operation experiments, including LHW heating to enhance plasma ionization during the current transition and current sustainment, is described. The behaviour of runaway electrons is analysed by four HXR detectors tangentially viewing the plasma in the equatorial plane, within energy ranges 0.3-1.2 MeV and 0.3-7 MeV, separately. High energy runaway electrons (~MeV) are found to circulate predominantly in the opposite direction to the plasma current, while the number of low energy runaway electrons (~tens to hundreds of keV) circulating along the plasma current is comparable to that in the direction opposite to the plasma current. AC operation with lower hybrid current drive (LHCD) is observed to have an additional benefit of suppressing the runaway electrons if the drop of the loop voltage is large enough.

  14. Electric-hydraulic car

    SciTech Connect

    Clark, R.W.; Greene, H.

    1993-07-27

    A propulsion system is described for a vehicle having a chassis and at least one drive wheel, the propulsion system including in combination: a constant speed power source comprising an alternating current electric motor operated at a constant speed corresponding to its optimum performance; a source of energy comprising a storage battery and an inverter connected to the electric motor for operating the electric motor of the constant speed power source; a hydraulic fluid system including a main hydraulic pump coupled with the electric motor of the constant speed power source and driven thereby; at least one hydraulic drive motor coupled with the hydraulic pump for receiving fluid flow therefrom; and means for varying the fluid flow through the main hydraulic pump to vary the speed of operation of the hydraulic drive motor.

  15. Space Charge Modulated Electrical Breakdown

    PubMed Central

    Li, Shengtao; Zhu, Yuanwei; Min, Daomin; Chen, George

    2016-01-01

    Electrical breakdown is one of the most important physical phenomena in electrical and electronic engineering. Since the early 20th century, many theories and models of electrical breakdown have been proposed, but the origin of one key issue, that the explanation for dc breakdown strength being twice or higher than ac breakdown strength in insulating materials, remains unclear. Here, by employing a bipolar charge transport model, we investigate the space charge dynamics in both dc and ac breakdown processes. We demonstrate the differences in charge accumulations under both dc and ac stresses and estimate the breakdown strength, which is modulated by the electric field distortion induced by space charge. It is concluded that dc breakdown initializes in the bulk whereas ac breakdown initializes in the vicinity of the sample-electrode interface. Compared with dc breakdown, the lower breakdown strength under ac stress and the decreasing breakdown strength with an increase in applied frequency, are both attributed to the electric field distortion induced by space charges located in the vicinity of the electrodes. PMID:27599577

  16. Space Charge Modulated Electrical Breakdown

    NASA Astrophysics Data System (ADS)

    Li, Shengtao; Zhu, Yuanwei; Min, Daomin; Chen, George

    2016-09-01

    Electrical breakdown is one of the most important physical phenomena in electrical and electronic engineering. Since the early 20th century, many theories and models of electrical breakdown have been proposed, but the origin of one key issue, that the explanation for dc breakdown strength being twice or higher than ac breakdown strength in insulating materials, remains unclear. Here, by employing a bipolar charge transport model, we investigate the space charge dynamics in both dc and ac breakdown processes. We demonstrate the differences in charge accumulations under both dc and ac stresses and estimate the breakdown strength, which is modulated by the electric field distortion induced by space charge. It is concluded that dc breakdown initializes in the bulk whereas ac breakdown initializes in the vicinity of the sample-electrode interface. Compared with dc breakdown, the lower breakdown strength under ac stress and the decreasing breakdown strength with an increase in applied frequency, are both attributed to the electric field distortion induced by space charges located in the vicinity of the electrodes.

  17. Space Charge Modulated Electrical Breakdown.

    PubMed

    Li, Shengtao; Zhu, Yuanwei; Min, Daomin; Chen, George

    2016-01-01

    Electrical breakdown is one of the most important physical phenomena in electrical and electronic engineering. Since the early 20(th) century, many theories and models of electrical breakdown have been proposed, but the origin of one key issue, that the explanation for dc breakdown strength being twice or higher than ac breakdown strength in insulating materials, remains unclear. Here, by employing a bipolar charge transport model, we investigate the space charge dynamics in both dc and ac breakdown processes. We demonstrate the differences in charge accumulations under both dc and ac stresses and estimate the breakdown strength, which is modulated by the electric field distortion induced by space charge. It is concluded that dc breakdown initializes in the bulk whereas ac breakdown initializes in the vicinity of the sample-electrode interface. Compared with dc breakdown, the lower breakdown strength under ac stress and the decreasing breakdown strength with an increase in applied frequency, are both attributed to the electric field distortion induced by space charges located in the vicinity of the electrodes. PMID:27599577

  18. Modernization of the control system and the electrical equipment of DSV vacuum arc furnaces

    NASA Astrophysics Data System (ADS)

    Dednev, A. A.; Kisselman, M. A.; Nekhamin, S. M.; Kalinin, V. I.; Koshelev, Yu. N.

    2010-06-01

    The results of modernizing one of the DSV-3.2-G1 arc furnaces at OAO Elektrostal’ Metallurgical Works are presented. New automatic control system ACS DSV-3.2 with functions of maintenance, control, and correction of the main technical parameters of vacuum arc remelting is created. The electric furnace is equipped with a modern visual control system for a heat and a unique inert gas (helium) supply system. The rod motion drive is replaced by a modern drive with frequency control of its motion velocity. New control cabinet and desk made of modern elements are mounted. Melting of a pilot series of EP-718 alloy ingots supports the high quality and reliability of the new control systems.

  19. Superluminal warp drive

    NASA Astrophysics Data System (ADS)

    González-Díaz, Pedro F.

    2007-09-01

    In this Letter we consider a warp drive spacetime resulting from that suggested by Alcubierre when the spaceship can only travel faster than light. Restricting to the two dimensions that retains most of the physics, we derive the thermodynamic properties of the warp drive and show that the temperature of the spaceship rises up as its apparent velocity increases. We also find that the warp drive spacetime can be exhibited in a manifestly cosmological form.

  20. Diabetes and driving.

    PubMed

    Inkster, B; Frier, B M

    2013-09-01

    The principal safety concern for driving for people treated with insulin or insulin secretagogues is hypoglycaemia, which impairs driving performance. Other complications, such as those causing visual impairment and peripheral neuropathy, are also relevant to medical fitness to drive. Case control studies have suggested that drivers with diabetes pose a modestly increased but acceptable and measurable risk of motor vehicle accidents compared to non-diabetic drivers, but many studies are limited and of poor quality. Factors which have been shown to increase driving risk include previous episodes of severe hypoglycaemia, previous hypoglycaemia while driving, strict glycaemic control (lower HbA1c) and absence of blood glucose monitoring before driving. Impaired awareness of hypoglycaemia may be counteracted by frequent blood glucose testing. The European Union Third directive on driving (2006) has necessitated changes in statutory regulations for driving licences for people with diabetes in all European States, including the UK. Stricter criteria have been introduced for Group 1 vehicle licences while those for Group 2 licences have been relaxed. Insulin-treated drivers can now apply to drive Group 2 vehicles, but in the UK must meet very strict criteria and be assessed by an independent specialist to be issued with a 1-year licence. PMID:23350766