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1

Multiple voltage electrical power distribution system for automotive applications  

Microsoft Academic Search

Over the course of the 20th Century, the automobile electrical system has experienced one architectural change, one significant electrical power plant change and one notable change in the electrical storage component. There is now growing disparity in voltage level requirements between electronic and electrical loads to the point that a single voltage system may no longer be the most efficient

John M. Miller

1996-01-01

2

New High Power \\/ High Voltage Battery-Free Bus for Electrical Propulsion in Satellites  

Microsoft Academic Search

In this paper a solution for the power conditioning and distribution unit (PCDU) of the solar electric propulsion module (SEPM) is proposed. The electronic propulsion system is made out of ion thrusters which need a very steady supply voltage and therefore care has to be taken during switch off of the ion thrusters (beam-out) to avoid transient overvoltages (they must

E. Maset; E. Sanchis-Kilders; J. B. Ejea; A. Ferreres; J. Jordan; V. Esteve; A. Garrigos; J. A. Carrasco; J. M. Blanes; A. H. Weinberg

2007-01-01

3

Data Transfer over A Low Voltage Power Line for Data Acquisition and Monitoring of Electrical Appliances  

Microsoft Academic Search

This article presents the design and implementation of a data communication system over a low voltage power line, meant primarily for applications of data acquisition from sites and monitoring of electrical appliances at the sites. The hardware developed, the interfacing required and the software used for implementation of the protocol are addressed. The developed system has been tested and results

S. Khan; J. Omar; O. O Khalifa; M. R. Islam; I. Adam; A. B. Hassan

2006-01-01

4

Investigations of the Quality of Hospital Electric Power Supply and the Tolerance of Medical Electric Devices to Voltage Dips  

Microsoft Academic Search

Medical devices driven by electric power have come to be commonly used in hospitals, and rapid changes of voltage or current\\u000a can easily cause them to fail. A stable and high quality power supply is indispensable in order to maintain safety in the\\u000a modern clinical setting. Therefore, we investigated the quality of the power supply in a hospital and determined

Eisuke Hanada; Shuuya Itoga; Kyoko Takano; Takato Kudou

2007-01-01

5

Generating Electrical Voltage  

NSDL National Science Digital Library

This interactive resource adapted from the Wisconsin Online Resource Center illustrates how electrical voltage is generated through a process called magnetic induction and describes some of the factors that affect the magnitude of the voltage produced.

WGBH Educational Foundation

2009-12-24

6

Effect of Voltage Level on Power System Design for Solar Electric Propulsion Missions  

NASA Technical Reports Server (NTRS)

This paper presents study results quantifying the benefits of higher voltage, electric power system designs for a typical solar electric propulsion spacecraft Earth orbiting mission. A conceptual power system architecture was defined and design points were generated for system voltages of 28-V, 50-V, 120-V, and 300-V using state-of-the-art or advanced technologies. A 300-V 'direct-drive' architecture was also analyzed to assess the benefits of directly powering the electric thruster from the photovoltaic array without up-conversion. Fortran and spreadsheet computational models were exercised to predict the performance and size power system components to meet spacecraft mission requirements. Pertinent space environments, such as electron and proton radiation, were calculated along the spiral trajectory. In addition, a simplified electron current collection model was developed to estimate photovoltaic array losses for the orbital plasma environment and that created by the thruster plume. The secondary benefits of power system mass savings for spacecraft propulsion and attitude control systems were also quantified. Results indicate that considerable spacecraft wet mass savings were achieved by the 300-V and 300-V direct-drive architectures.

Kerslake, Thomas W.

2003-01-01

7

Technical evaluation of the adequacy of station electric distribution system voltages for the Yankee Rowe Nuclear Power Station  

Microsoft Academic Search

This report documents the technical evaluation of the adequacy of the station electric distribution system voltages for the Yankee Rowe Nuclear Power Station. The evaluation is to determine if the onsite distribution system, in conjunction with the offsite power sources, has sufficient capacity to automatically start and operate all Class 1E loads within the equipment voltage ratings under certain conditions

Selan

1981-01-01

8

Relationship between voltage instability and multiple load flow solutions in electric power systems  

SciTech Connect

There have been observed several voltage instability phenomena in electric power systems where receiving end voltages oscillate remarkably or get much lower than the nominal values. Those phenomena tend to occur in heavy loaded conditions and seem to be related to the multiple load flow solution problem for the following reasons. It has been confirmed analytically and by simulations that the multiple load flow solutions are likely to appear under the heavy-loaded conditions, and that the individual solutions of the solution pair have different features from each other, from the standpoint of stability, although they are close to each other. It is hard to solve the voltage instability problem at a stretch since dynamic factors get involved in this problem and thus a high dimentional and multi-parameter system has to be dealt with. It may be wise to analyze, first of all, static and/or semidynamic performances of this problem, which could be approached more or less systematically. Next, the relationship between the dynamic factors and voltage instability will be analyzed and evaluated. Following the way of thinking above, this paper proposes a sequence of criteria which are applied to the individual members of a solution pair of the load flow to see their difference in behavior. The relationship between the voltage instability and closely-located solution pair is analyzed from various viewpoints for power systems of different types and sizes.

Tamura, Y.; Iwamoto, S.; Mori, H.

1983-05-01

9

Electric power high-voltage transmission lines: Design options, cost, and electric and magnetic field levels  

SciTech Connect

This report provides background information about (1) the electric and magnetic fields (EMFs) of high-voltage transmission lines at typical voltages and line configurations and (2) typical transmission line costs to assist on alternatives in environmental documents. EMF strengths at 0 {+-} 200 ft from centerline were calculated for ac overhead lines, and for 345 and 230-kV ac underground line and for a {+-}450-kV dc overhead line. Compacting and height sensitivity factors were computed for the variation in EMFs when line conductors are moved closer or raised. Estimated costs for the lines are presented and discussed so that the impact of using alternative strategies for reducing EMF strengths and the implications of implementing the strategies can be better appreciated.

Stoffel, J.B.; Pentecost, E.D.; Roman, R.D.; Traczyk, P.A.

1994-11-01

10

Characterization of vertical electric fields and associated voltages induced on a overhead power line from close artificially initiated lightning  

NASA Technical Reports Server (NTRS)

Measurements were characterized of simultaneous vertical electric fields and voltages induced at both ends of a 448 m overhead power line by artificially initiated lightning return strokes. The lightning discharges struck ground about 20 m from one end of the line. The measured line voltages could be grouped into two categories: those in which multiple, similarly shaped, evenly spaced pulses were observed, which are called oscillatory; and those dominated by a principal pulse with subsidiary oscillations of much smaller amplitude, which are called impulsive. Voltage amplitudes range from tens of kilovolts for oscillatory voltages to hundreds of kilovolts for impulsive voltages.

Rubinstein, Marcos; Uman, Martin A.; Thomson, Ewen M.; Medelius, Pedro J.

1991-01-01

11

Load insensitive electrical device. [power converters for supplying direct current at one voltage from a source at another voltage  

NASA Technical Reports Server (NTRS)

A class of power converters is described for supplying direct current at one voltage from a source at another voltage. It includes a simple passive circuit arrangement of solid-state switches, inductors, and capacitors by which the output voltage of the converter tends to remain constant in spite of changes in load. The switches are sensitive to the current flowing in the circuit and are employed to permit the charging of capacitance devices in accordance with the load requirements. Because solid-state switches (such as SCR's) may be used with relatively high voltage and because of the inherent efficiency of the invention that permits relatively high switching frequencies, power supplies built in accordance with the invention, together with their associated cabling, can be substantially lighter in weight for a given output power level and efficiency of operation than systems of the prior art.

Schwarz, F. C. (inventor)

1974-01-01

12

High voltage-power frequency electrical heating in-situ conversion technology of oil shale  

NASA Astrophysics Data System (ADS)

With the depletion of conventional energy sources,oil shale has got much attention as a new type of energy resource,which is rich and widespread in the world.The conventional utilization of oil shale is mainly focused on resorting to produce shale oil and fuel gas with low extraction efficiency about one in a million due to many shortcomings and limitations.And the in-situ conversion of oil shale,more environmentally friendly,is still in the experimental stage.High voltage-power frequency electrical heating in-situ conversion of oil shale is a new type of in-situ pyrolysis technology.The main equipment includes a high voltage-power frequency generator and interior reactor. The high voltage-power frequency generator can provide a voltage between 220-8000 V which can be adjusted in real time according to the actual situation.Firstly,high voltage is used to breakdown the oil shale to form a dendritic crack between two electrodes providing a conductive channel inside the oil shale rock.And then the power frequency(220V) is used to generate the electric current for heating the internal surface of conductive channel,so that the energy can be transmitted to the surrounding oil shale.When the temperature reaches 350 degree,the oil shale begins to pyrolysis.In addition,the temperature in the conductive channel can be extremely high with high voltage,which makes the internal surface of conductive channel graphitization and improves its heat conduction performance.This technology can successfully make the oil shale pyrolysis, based on a lot of lab experiments,and also produce the combustible shale oil and fuel gas.Compared to other in-situ conversion technology,this method has the following advantages: high speed of heating oil shale,the equipment underground is simple,and easy to operate;it can proceed without the limitation of shale thickness, and can be used especially in the thin oil shale reservoir;the heating channel is parallel to the oil shale layers,which has more effective area for heating and heat transmitting;it has very good adaptability to the formation,the location and depth of the electrodes which can be adjusted according to the specific stratigraphic depth case;A positive(negative) electrode can be connected to multiple negative(positive) electrodes,and the arrangement of the positive and negative electrodes can be evaluated for improving the extraction efficiency.High voltage-power frequency electrical heating in-situ conversion technology is a very promising in-situ pyrolysis method,which could provide a new way of mining oil shale resources.

Sun, Youhong; Yang, Yang; Lopatin, Vladimir; Guo, Wei; Liu, Baochang; Yu, Ping; Gao, Ke; Ma, Yinlong

2014-05-01

13

Feasibility of power electronic converters for low-voltage (42 V) SRM drives in mildly hybrid electric traction systems  

Microsoft Academic Search

The more electric car (MEC) concept emphasizes utilizing electrical power to drive more automotive conventional systems and to facilitate new introduced luxury loads. Improving fuel economy, emissions, reliability, and comfort are the main motivations towards the MEC concept, which necessitates going to a higher system voltage such as the proposed 42 V. This paper presents that the 42 V system

Ali Emadi

2001-01-01

14

Generating Electrical Voltage  

NSDL National Science Digital Library

Teachers' Domain presents this interactive lesson designed to help students "learn how a generator converts mechanical energy into electrical energy. Investigate the principle of magnetic induction by moving a conductor through a magnetic field to see how voltage is generated." The lesson is divided into three major sections: How Do Generators Work?, What Factors Influence Voltage Strength?, and What Determines Voltage Polarity? There are plenty of animations to help students visualize the processes at work in electricity generation. On the site, visitors will also find a supplemental background essay, discussion questions, and standards alignment from Teachers' Domain.

15

Voltage profile program for the Kennedy Space Center electric power distribution system  

NASA Technical Reports Server (NTRS)

The Kennedy Space Center voltage profile program computes voltages at all busses greater than 1 Kv in the network under various conditions of load. The computation is based upon power flow principles and utilizes a Newton-Raphson iterative load flow algorithm. Power flow conditions throughout the network are also provided. The computer program is designed for both steady state and transient operation. In the steady state mode, automatic tap changing of primary distribution transformers is incorporated. Under transient conditions, such as motor starts etc., it is assumed that tap changing is not accomplished so that transformer secondary voltage is allowed to sag.

1976-01-01

16

Environmental justice: a contrary finding for the case of high-voltage electric power transmission lines.  

PubMed

Environmental justice is the consideration of whether minority and/or lower-income residents in a geographic area are likely to have disproportionately higher exposures to environmental toxins than those living elsewhere. Such situations have been identified for a variety of factors, such as air pollution, hazardous waste, water quality, noise, residential crowding, and housing quality. This study investigates the application of this concept to high-voltage electric power transmission lines (HVTL), which some perceive as a health risk because of the magnetic fields they generate, and also as esthetically unpleasing. We mapped all 345 kV and higher voltage HVTL in New York State and extracted and summarized proximate US Census sociodemographic and housing characteristic data into four categories on the basis of distances from HVTL. Contrary to our expectation, people living within 2000 ft from HVTL were more likely to be exposed to magnetic fields, white, of higher income, more educated and home owners, than those living farther away, particularly in urban areas. Possible explanations for these patterns include the desire for the open space created by the rights-of-way, the preference for new homes/subdivisions that are often located near HVTL, and moving closer to HVTL before EMFs were considered a risk. This study suggests that environmental justice may not apply to all environmental risk factors and that one must be cautious in generalizing. In addition, it shows the utility of geographical information system methodology for summarizing information from extremely large populations, often a challenge in epidemiology. PMID:19352413

Wartenberg, Daniel; Greenberg, Michael R; Harris, Gerald

2010-05-01

17

Power Electronics Building Block (PEBB) for Static Conversion Apparatus Devoted to Low-Voltage Fed Electric Drives  

Microsoft Academic Search

This paper investigates the potential use of the PEBB concept in low-voltage fed power converters, such as those being currently utilized in particular traction drives (e.g. forklift drives or wheelchair drives) or those being envisaged to be soon utilized on board automobiles being equipped with a 42 V electric power system including both engine directly-coupled starter\\/alternator and ultracapacitor-based storage system.

F. Crescimbini; V. Serrao; L. Solero

2005-01-01

18

Power quality assessment in electrical utilities including distributed generation unit & hybrid filters under non-ideal source voltage  

Microsoft Academic Search

This paper deals with a hybrid compensation system in electrical utility including a distributed generation (DG) unit under non-ideal source voltages condition. The DG unit consists of a Solid Oxide Fuel Cell (SOFC) as active power source and a three-phase full-bridge DC-AC inverter for power conversion. DG unit is controlled to deliver balanced and sinusoidal current in phase with fundamental

S. H. Hosseini; T. Nouri

2011-01-01

19

Medium factors of electrical insulation systems in high temperature superconducting power apparatus with coil structure for equivalent ac withstand voltage test at room temperature  

Microsoft Academic Search

Equivalent insulation test voltage at room temperature of high temperature superconducting (HTS) power apparatus with coil structure for power frequency withstand voltage tests is discussed based on medium factors of insulation weak parts in electrical insulation elements of the HTS power apparatus. Uniform and non-uniform field gaps, triple junction and solid insulator surface are selected as the insulation weak parts,

M. Hara; T. Kurihara; R. Nakano; J. Suehiro

2005-01-01

20

Residual voltage of the electrical equipment  

NASA Astrophysics Data System (ADS)

The rapid development of electronic products today, it is a very important part of that electric shock prevention remains the safety design of electronic products. When unplug the electrical equipment, the voltage in each pin of the plug is residual voltage. If residual voltage is too large, it may cause harm to human body, must attach importance to it and precisely measure it. Load of different electrical products lead to different transient voltage changes in sudden power-down, namely the changes in the residual voltage. In this paper, the load on the electrical equipment on the basis of type classification, focusing on the design of their corresponding capacitive load and peak power detection circuit link was simulated, thus arrive at the variation discipline of residual voltage, in order to better protect human safety.

Yuan, Jia; Qian, Xiaoyao; Qian, Jiawei

2010-08-01

21

Design of 154 kV Extra-High-Voltage Prototype SF6 Bushing for Superconducting Electric Power Applications  

NASA Astrophysics Data System (ADS)

One of the critical components to be developed for high-voltage superconducting devices, such as superconducting transformers, cables, and fault current limiters, is a high-voltage bushing to supply a high current to devices without insulation difficulties in cryogenic environments. Unfortunately, suitable bushings for high-temperature-superconductivity (HTS) equipment have not been fully developed to address cryogenic insulation issues. As a fundamental step towards developing the optimum design of the 154 kV prototype SF6 bushing of HTS devices, the puncture and creepage breakdown voltages of glass-fiber-reinforced-plastic (GFRP) were analyzed with a variety of configurations of electrodes and gap distances in the insulation material. And design factors of high-voltage cryogenic bushings were obtained from the result of tests. Finally, the withstand voltage tests of manufacturing a 154 kV extra-high-voltage (EHV) prototype bushing has been performed. Consequently, we verified the insulation level of the newly designed 154 kV EHV cryogenic prototype bushings for superconducting electric power applications.

Koo, Ja-yoon; Seong, Jae-gyu; Hwang, Jae-sang; Lee, Bang-wook; Lee, Sang-hwa

2012-09-01

22

High voltage power supply  

NASA Technical Reports Server (NTRS)

A high voltage power supply is formed by three discrete circuits energized by a battery to provide a plurality of concurrent output signals floating at a high output voltage on the order of several tens of kilovolts. In the first two circuits, the regulator stages are pulse width modulated and include adjustable ressistances for varying the duty cycles of pulse trains provided to corresponding oscillator stages while the third regulator stage includes an adjustable resistance for varying the amplitude of a steady signal provided to a third oscillator stage. In the first circuit, the oscillator, formed by a constant current drive network and a tuned resonant network included a step up transformer, is coupled to a second step up transformer which, in turn, supplies an amplified sinusoidal signal to a parallel pair of complementary poled rectifying, voltage multiplier stages to generate the high output voltage.

Ruitberg, A. P.; Young, K. M. (inventors)

1985-01-01

23

6. Electric current is delivered to a television set at a specified voltage. The power delivered to the television is the energy per charge (voltage) multiplied by the charge per time (current) as  

E-print Network

1 Chapter 21 6. Electric current is delivered to a television set at a specified voltage. The power.1 10 m 4 4 2.1 A 6.9 m L L D V V IR I I A I LD - - Ã? = = = = = = Ã? 29. An electric heater converts electric power to heat energy. Equation 21-6 gives the rate at which power is consumed

Kioussis, Nicholas

24

Electrical system architecture having high voltage bus  

DOEpatents

An electrical system architecture is disclosed. The architecture has a power source configured to generate a first power, and a first bus configured to receive the first power from the power source. The architecture also has a converter configured to receive the first power from the first bus and convert the first power to a second power, wherein a voltage of the second power is greater than a voltage of the first power, and a second bus configured to receive the second power from the converter. The architecture further has a power storage device configured to receive the second power from the second bus and deliver the second power to the second bus, a propulsion motor configured to receive the second power from the second bus, and an accessory motor configured to receive the second power from the second bus.

Hoff, Brian Douglas (East Peoria, IL); Akasam, Sivaprasad (Peoria, IL)

2011-03-22

25

High voltage DC power supply  

DOEpatents

A high voltage DC power supply having a first series resistor at the output for limiting current in the event of a short-circuited output, a second series resistor for sensing the magnitude of output current, and a voltage divider circuit for providing a source of feedback voltage for use in voltage regulation is disclosed. The voltage divider circuit is coupled to the second series resistor so as to compensate the feedback voltage for a voltage drop across the first series resistor. The power supply also includes a pulse-width modulated control circuit, having dual clock signals, which is responsive to both the feedback voltage and a command voltage, and also includes voltage and current measuring circuits responsive to the feedback voltage and the voltage developed across the second series resistor respectively. 7 figs.

Droege, T.F.

1989-12-19

26

High voltage DC power supply  

DOEpatents

A high voltage DC power supply having a first series resistor at the output for limiting current in the event of a short-circuited output, a second series resistor for sensing the magnitude of output current, and a voltage divider circuit for providing a source of feedback voltage for use in voltage regulation is disclosed. The voltage divider circuit is coupled to the second series resistor so as to compensate the feedback voltage for a voltage drop across the first series resistor. The power supply also includes a pulse-width modulated control circuit, having dual clock signals, which is responsive to both the feedback voltage and a command voltage, and also includes voltage and current measuring circuits responsive to the feedback voltage and the voltage developed across the second series resistor respectively.

Droege, Thomas F. (Batavia, IL)

1989-01-01

27

Aircraft Electric Secondary Power  

NASA Technical Reports Server (NTRS)

Technologies resulted to aircraft power systems and aircraft in which all secondary power is supplied electrically are discussed. A high-voltage dc power generating system for fighter aircraft, permanent magnet motors and generators for aircraft, lightweight transformers, and the installation of electric generators on turbine engines are among the topics discussed.

1983-01-01

28

Electrical safety for high voltage arrays  

NASA Technical Reports Server (NTRS)

A number of key electrical safety requirements for the high voltage arrays of central station photovoltaic power systems are explored. The suitability of representative industrial DC power switchgear for control and fault protection was evaluated. Included were AC/DC circuit breakers, electromechanical contactors and relays, load interruptors, cold disconnect devices, sectionalizing switches, and high voltage DC fuses. As appropriate, steady state and transient characteristics were analyzed. Failure modes impacting upon operation and maintenance safety were also identified, as were the voltage withstand and current interruption levels.

Marshall, N. A.

1983-01-01

29

Spacecraft high-voltage power supply construction  

NASA Technical Reports Server (NTRS)

The design techniques, circuit components, fabrication techniques, and past experience used in successful high-voltage power supplies for spacecraft flight systems are described. A discussion of the basic physics of electrical discharges in gases is included and a design rationale for the prevention of electrical discharges is provided. Also included are typical examples of proven spacecraft high-voltage power supplies with typical specifications for design, fabrication, and testing.

Sutton, J. F.; Stern, J. E.

1975-01-01

30

Lightning Induced Voltages on Power Lines: Experiment  

Microsoft Academic Search

The authors present correlated measurements of the voltage induced on a power line by nearby lightning and the vertical electric field intensity from that lightning. Data are given for more than 100 first strokes and more than 200 subsequent strokes with the lightning ground strike point located by triangulation using a network of television cameras and by thunder ranging. Voltages

Maneck J. Master; Martin A. Uman; William Beasley; Mat Darveniza

1984-01-01

31

Efficient design and simulation of an expandable hybrid (wind–photovoltaic) power system with MPPT and inverter input voltage regulation features in compliance with electric grid requirements  

Microsoft Academic Search

In this paper an efficient design along with modeling and simulation of a transformer-less small-scale centralized DC—bus Grid Connected Hybrid (Wind–PV) power system for supplying electric power to a single phase of a three phase low voltage (LV) strong distribution grid are proposed and presented. The main components of the hybrid system are: a PV generator (PVG); and an array

Sotirios B. Skretas; Demetrios P. Papadopoulos

2009-01-01

32

Nanosecond pulsed electric fields (nsPEFs) low cost generator design using power MOSFET and Cockcroft-Walton multiplier circuit as high voltage DC source  

NASA Astrophysics Data System (ADS)

Purpose: Non-ionizing radiation therapy for cancer using pulsed electric field with high intensity field has become an interesting field new research topic. A new method using nanosecond pulsed electric fields (nsPEFs) offers a novel means to treat cancer. Not like the conventional electroporation, nsPEFs able to create nanopores in all membranes of the cell, including membrane in cell organelles, like mitochondria and nucleus. NsPEFs will promote cell death in several cell types, including cancer cell by apoptosis mechanism. NsPEFs will use pulse with intensity of electric field higher than conventional electroporation, between 20-100 kV/cm and with shorter duration of pulse than conventional electroporation. NsPEFs requires a generator to produce high voltage pulse and to achieve high intensity electric field with proper pulse width. However, manufacturing cost for creating generator that generates a high voltage with short duration for nsPEFs purposes is highly expensive. Hence, the aim of this research is to obtain the low cost generator design that is able to produce a high voltage pulse with nanosecond width and will be used for nsPEFs purposes. Method: Cockcroft-Walton multiplier circuit will boost the input of 220 volt AC into high voltage DC around 1500 volt and it will be combined by a series of power MOSFET as a fast switch to obtain a high voltage with nanosecond pulse width. The motivation using Cockcroft-Walton multiplier is to acquire a low-cost high voltage DC generator; it will use capacitors and diodes arranged like a step. Power MOSFET connected in series is used as voltage divider to share the high voltage in order not to damage them. Results: This design is expected to acquire a low-cost generator that can achieve the high voltage pulse in amount of -1.5 kV with falltime 3 ns and risetime 15 ns into a 50? load that will be used for nsPEFs purposes. Further detailed on the circuit design will be explained at presentation.

Sulaeman, M. Y.; Widita, R.

2014-09-01

33

Nanosecond pulsed electric fields (nsPEFs) low cost generator design using power MOSFET and Cockcroft-Walton multiplier circuit as high voltage DC source  

SciTech Connect

Purpose: Non-ionizing radiation therapy for cancer using pulsed electric field with high intensity field has become an interesting field new research topic. A new method using nanosecond pulsed electric fields (nsPEFs) offers a novel means to treat cancer. Not like the conventional electroporation, nsPEFs able to create nanopores in all membranes of the cell, including membrane in cell organelles, like mitochondria and nucleus. NsPEFs will promote cell death in several cell types, including cancer cell by apoptosis mechanism. NsPEFs will use pulse with intensity of electric field higher than conventional electroporation, between 20–100 kV/cm and with shorter duration of pulse than conventional electroporation. NsPEFs requires a generator to produce high voltage pulse and to achieve high intensity electric field with proper pulse width. However, manufacturing cost for creating generator that generates a high voltage with short duration for nsPEFs purposes is highly expensive. Hence, the aim of this research is to obtain the low cost generator design that is able to produce a high voltage pulse with nanosecond width and will be used for nsPEFs purposes. Method: Cockcroft-Walton multiplier circuit will boost the input of 220 volt AC into high voltage DC around 1500 volt and it will be combined by a series of power MOSFET as a fast switch to obtain a high voltage with nanosecond pulse width. The motivation using Cockcroft-Walton multiplier is to acquire a low-cost high voltage DC generator; it will use capacitors and diodes arranged like a step. Power MOSFET connected in series is used as voltage divider to share the high voltage in order not to damage them. Results: This design is expected to acquire a low-cost generator that can achieve the high voltage pulse in amount of ?1.5 kV with falltime 3 ns and risetime 15 ns into a 50? load that will be used for nsPEFs purposes. Further detailed on the circuit design will be explained at presentation.

Sulaeman, M. Y.; Widita, R. [Department of Physics, Nuclear Physics and Biophysics Research Division, Faculty of Mathematics and Natural Science, Institut Teknologi Bandung, Bandung (Indonesia)

2014-09-30

34

Power-MOSFET Voltage Regulator  

NASA Technical Reports Server (NTRS)

Ninety-six parallel MOSFET devices with two-stage feedback circuit form a high-current dc voltage regulator that also acts as fully-on solid-state switch when fuel-cell out-put falls below regulated voltage. Ripple voltage is less than 20 mV, transient recovery time is less than 50 ms. Parallel MOSFET's act as high-current dc regulator and switch. Regulator can be used wherever large direct currents must be controlled. Can be applied to inverters, industrial furnaces photovoltaic solar generators, dc motors, and electric autos.

Miller, W. N.; Gray, O. E.

1982-01-01

35

Voltages induced by lightning on electric power distribution lines: Field data and analysis results for the period July 1984-1986  

SciTech Connect

Measurements have been made during 1984 and 1985 at the NASA Kennedy Space Center, Florida using a newly-developed spherical antenna of the time-domain horizontal and vertical electric fields from lightning return strokes. Statistics are presented for the fields of 42 return strokes. The peak horizontal field was about 0.03 of the peak critical field; the horizontal field had a mean risetime and a falltime to half value about 0.3 ..mu..s prior to the peak in the vertical field. Voltage has also been measured at one end of an unenergized power distribution line about 500 m in length and 10 m in height. Tables of measured peak voltages are given. By way of a newly-written computer program, the line voltage has been calculated using the measured fields as inputs. Agreement between the voltage measurement and theory is generally good. The lightning horizontal electric field can significantly contribute to the induced line voltage. The horizontal fields become larger as the earth conductivity decreases. 16 figs., 3 tabs.

Thomson, E.M.

1988-03-01

36

Low Voltage Power Supply Incorporating Ceramic Transformer  

E-print Network

A low voltage power supply provides the regulated output voltage of 1 V from the supply voltage around 48 V. The low voltage power supply incorporates a ceramic transformer which utilizes piezoelectric effect to convert voltage. The ceramic transformer isolates the secondary from the primary, thus providing the ground isolation between the supply and the output voltages. The ceramic transformer takes the place of the conventional magnetic transformer. The ceramic transformer is constructed from a ceramic bar and does not include any magnetic material. So the low voltage power supply can operate under a magnetic field. The output voltage is stabilized by feedback. A feedback loop consists of an error amplifier, a voltage controlled oscillator and a driver circuit. The amplitude ratio of the transformer has dependence on the frequency, which is utilized to stabilize the output voltage. The low voltage power supply is investigated on the analogy of the high voltage power supply similarly incorporating the cerami...

Imori, M

2007-01-01

37

High voltage photovoltaic power converter  

DOEpatents

An array of independently connected photovoltaic cells on a semi-insulating substrate contains reflective coatings between the cells to enhance efficiency. A uniform, flat top laser beam profile is illuminated upon the array to produce electrical current having high voltage. An essentially wireless system includes a laser energy source being fed through optic fiber and cast upon the photovoltaic cell array to prevent stray electrical signals prior to use of the current from the array. Direct bandgap, single crystal semiconductor materials, such as GaAs, are commonly used in the array. Useful applications of the system include locations where high voltages are provided to confined spaces such as in explosive detonation, accelerators, photo cathodes and medical appliances.

Haigh, Ronald E. (Arvada, CO); Wojtczuk, Steve (Cambridge, MA); Jacobson, Gerard F. (Livermore, CA); Hagans, Karla G. (Livermore, CA)

2001-01-01

38

Lightning induced voltages on power lines: experiment  

SciTech Connect

The authors present correlated measurements of the voltage induced on a power line by nearby lightning and the vertical electric field intensity from that lightning. Data are given for more than 100 first strokes and more than 200 subsequent strokes with the lightning ground strike point located by triangulation using a network of television cameras and by thunder ranging. Voltages were measured at one end of a 460 m unenergized distribution line which was open-circuited at both ends. A neutral wire was located beneath the line and was grounded at both ends. The time-domain voltage and vertical electric field waveforms were detected and recorded on a system having a frequency response from less than 1 Hz to over 1 MHz. Only about half of the voltage wave forms resemble the ''classical induced positive surges'' described in the literature. The magnitude and polarity of the peak induced voltage is a strong function of the location of the lightning ground strike point.

Master, M.J.; Beasley, W.; Darveniza, M.; Uman, M.A.

1984-09-01

39

Reactive power management and voltage control in deregulated power markets  

NASA Astrophysics Data System (ADS)

The research that is the subject of this dissertation is about the management of reactive power and voltage support in the wholesale open access power markets in the United States (US). The purpose of this research is to place decisions about open access market structures, as they relate to reactive power and voltage control, on a logical and consistent economic basis, given the engineering needs of a commercial electric power system. An examination of the electricity markets operating in the US today reveals that current approaches to reactive power management and voltage support are extensions of those based on historical, regulated monopoly electric service. A case for change is built by first looking at the subject of reactive power from an engineering viewpoint and then from an economic perspective. Ultimately, a set of market rules for managing reactive power and voltage support is proposed. The proposal suggests that cost recovery for static and dynamic VARs is appropriately accomplished through the regulated transmission cost of service. Static VAR cost recovery should follow traditional rate recovery methodologies. In the case of dynamic VARs, this work provides a methodology based on the microeconomic theory of the firm for determining such cost. It further suggests that an operational strategy that reduces and limits the use of dynamic VARs, during normal operations, is appropriate. This latter point leads to an increase in the fixed cost of the transmission network but prevents price spikes and short supply situations from affecting, or being affected by, the reactive capability limitations associated with dynamic VARs supplied from synchronous generators. The rules are consistent with a market structure that includes competitive generation and their application will result in the communication of a clear understanding of the responsibilities, related to voltage control, of each type of market entity. In this sense, their application will contribute to the efficient functioning of the wholesale open access markets.

Spangler, Robert G.

40

Electrical safety and touch voltage design  

Microsoft Academic Search

The provision of safe and reliable means to afford protection against electric shock in the built environment is deemed one of the most important design elements for electrical services engineers who design low voltage electrical installations to conform to BS7671: 2008 (17th edition IEE Wiring Regulations) and ET 101:2008. The fact that, domestic properties rank as one of the leading

M. Barrett; K. OConnell; C. M. A. Sung

2010-01-01

41

Low power, scalable multichannel high voltage controller  

Microsoft Academic Search

A low voltage control circuit is provided for individually controlling high voltage power provided over bus lines to a multitude of interconnected loads. An example of a load is a drive for capillary channels in a microfluidic system. Control is distributed from a central high voltage circuit, rather than using a number of large expensive central high voltage circuits to

James Frederick Stamps; Robert Ward Crocker; Daniel Dadwa Yee; David Wright Dils

2006-01-01

42

Low power, scalable multichannel high voltage controller  

Microsoft Academic Search

A low voltage control circuit is provided for individually controlling high voltage power provided over bus lines to a multitude of interconnected loads. An example of a load is a drive for capillary channels in a microfluidic system. Control is distributed from a central high voltage circuit, rather than using a number of large expensive central high voltage circuits to

James Frederick Stamps; Robert Ward Crocker; Daniel Dadwa Yee; David Wright Dils

2008-01-01

43

Transformers with voltage regulation for electric supply networks  

NASA Astrophysics Data System (ADS)

Power transformers for electric supply networks in which the necessary voltage regulation and compensation of reactive power are effected through switching of the magnetic flux by superconducting shields are described. The performance characteristics, including the shielding action, are analyzed for appropriate equivalent circuit diagrams and the corresponding system of Kirchhoff equations. Voltages and currents are calculated by matrix notation. With the shield impedance ratio Z sub sh/jwL sub sh variable from 0 to oo, the transformer input impedance and output voltage is regulated simultaneously.

Yakimets, I. V.; Narovlyanskiy, V. G.; Matveykin, V. M.

1984-05-01

44

On the reliability of voltage and power as input parameters for the characterization of high power ultrasound applications  

NASA Astrophysics Data System (ADS)

For power levels up to 200 W and sonication times up to 60 s, the electrical power, the voltage and the electrical impedance (more exactly: the ratio of RMS voltage and RMS current) have been measured for a piezocomposite high intensity therapeutic ultrasound (HITU) transducer with integrated matching network, two piezoceramic HITU transducers with external matching networks and for a passive dummy 50 ? load. The electrical power and the voltage were measured during high power application with an inline power meter and an RMS voltage meter, respectively, and the complex electrical impedance was indirectly measured with a current probe, a 100:1 voltage probe and a digital scope. The results clearly show that the input RMS voltage and the input RMS power change unequally during the application. Hence, the indication of only the electrical input power or only the voltage as the input parameter may not be sufficient for reliable characterizations of ultrasound transducers for high power applications in some cases.

Haller, Julian; Wilkens, Volker

2012-11-01

45

Index-based reactive power compensation scheme for voltage regulation  

Microsoft Academic Search

Increasing demand for electrical power arising from deregulation and the restrictions posed to the construction of new transmission lines by environment, socioeconomic, and political issues had led to higher grid loading. Consequently, voltage instability has become a major concern, and reactive power support is vital to enhance transmission grid performance. Improved reactive power support to distressed grid is possible through

Damian Obioma Dike

2008-01-01

46

Electrical Properties of Skin at Moderate Voltages  

Microsoft Academic Search

The electrical properties of human skin in the range of the applied voltages between 0.2 and 60V are modeled theoretically and measured experimentally. Two parallel electric current pathways are considered: one crossing lipid-corneocyte matrix and the other going through skin appendages. The appendageal ducts are modeled as long tubes with distributed electrical parameters. For both transport systems, equations taking into

Yuri A. Chizmadzhev; Andrey V. Indenbom; Peter I. Kuzmin; Sergey V. Galichenko; James C. Weaver; Russell O. Potts

1998-01-01

47

Electrically powered hand tool  

DOEpatents

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.

Myers, Kurt S.; Reed, Teddy R.

2007-01-16

48

Using PSpice in teaching impulse Voltage testing of power transformers to senior undergraduate students  

Microsoft Academic Search

This paper describes an efficient method of teaching impulse voltage testing of power transformers to undergraduate students of power system groups in electrical engineering departments, as a part of a high-voltage course for senior undergraduate students. The paper shows how to simulate the power transformer and impulse generator to teach students the basics of impulse voltage testing of power transformers

Behrooz Vahidi; Jamal Beiza

2005-01-01

49

Living and Working Safely Around High-Voltage Power Lines.  

SciTech Connect

High-voltage transmission lines can be just as safe as the electrical wiring in the homes--or just as dangerous. The crucial factor is ourselves: they must learn to behave safely around them. This booklet is a basic safety guide for those who live and work around power lines. It deals primarily with nuisance shocks due to induced voltages, and with potential electric shock hazards from contact with high-voltage lines. References on possible long-term biological effects of transmission lines are shown. In preparing this booklet, the Bonneville Power Administration has drawn on more than 50 years of experience with high-voltage transmission. BPA operates one of the world`s largest networks of long-distance, high-voltage lines. This system has more than 400 substations and about 15,000 miles of transmission lines, almost 4,400 miles of which are operated at 500,000 volts.

United States. Bonneville Power Administration.

2001-06-01

50

Wind Power Plant Voltage Stability Evaluation: Preprint  

SciTech Connect

Voltage stability refers to the ability of a power system to maintain steady voltages at all buses in the system after being subjected to a disturbance from a given initial operating condition. Voltage stability depends on a power system's ability to maintain and/or restore equilibrium between load demand and supply. Instability that may result occurs in the form of a progressive fall or rise of voltages of some buses. Possible outcomes of voltage instability are the loss of load in an area or tripped transmission lines and other elements by their protective systems, which may lead to cascading outages. The loss of synchronism of some generators may result from these outages or from operating conditions that violate a synchronous generator's field current limit, or in the case of variable speed wind turbine generator, the current limits of power switches. This paper investigates the impact of wind power plants on power system voltage stability by using synchrophasor measurements.

Muljadi, E.; Zhang, Y. C.

2014-09-01

51

Radio-frequency powered glow discharge device and method with high voltage interface  

Microsoft Academic Search

A high voltage accelerating potential, which is supplied by a high voltage direct current power supply, is applied to the electrically conducting interior wall of an RF powered glow discharge cell. The RF power supply desirably is electrically grounded, and the conductor carrying the RF power to the sample held by the probe is desirably shielded completely excepting only the

Douglas C. Duckworth; R. Kenneth Marcus; David L. Donohue; Trousdale A. Lewis

1994-01-01

52

Static power conditioner using GTO converters for AC electric railway  

Microsoft Academic Search

This paper proposes a static power conditioner (SPC) using self-commutated inverters in order to solve the problems of an AC electric railway. For compensating the voltage unbalance of a three-phase electric power system, the SPC controls the electric power in railway substations. Besides, for compensating the voltage drop in the feeding circuit, the SPC controls the reactive power in sectioning

Y. Mochinaga; Y. Hisamizu; M. Takeda; T. Miyashita; K. Hasuike

1993-01-01

53

Critical Voltage for Electrical Degradation of GaN High-Electron Mobility Transistors  

Microsoft Academic Search

We have found that there is a critical drain-to-gate voltage beyond which GaN high-electron mobility transistors start to degrade in electrical-stress experiments. The critical voltage depends on the detailed voltage biasing of the device during electrical stress. It is higher in the OFF state and high-power state than at VDS = 0. In addition, as |VGS| increases, the critical voltage

Jungwoo Joh; JesÚs A. del Alamo

2008-01-01

54

Piezoelectric transformer and modular connections for high power and high voltage power supplies  

NASA Technical Reports Server (NTRS)

A modular design for combining piezoelectric transformers is provided for high voltage and high power conversion applications. The input portions of individual piezoelectric transformers are driven for a single power supply. This created the vibration and the conversion of electrical to electrical energy from the input to the output of the transformers. The output portions of the single piezoelectric transformers are combining in series and/or parallel to provide multiple outputs having different rating of voltage and current.

Vazquez Carazo, Alfredo (Inventor)

2006-01-01

55

Low power, scalable multichannel high voltage controller  

DOEpatents

A low voltage control circuit is provided for individually controlling high voltage power provided over bus lines to a multitude of interconnected loads. An example of a load is a drive for capillary channels in a microfluidic system. Control is distributed from a central high voltage circuit, rather than using a number of large expensive central high voltage circuits to enable reducing circuit size and cost. Voltage is distributed to each individual load and controlled using a number of high voltage controller channel switches connected to high voltage bus lines. The channel switches each include complementary pull up and pull down photo isolator relays with photo isolator switching controlled from the central high voltage circuit to provide a desired bus line voltage. Switching of the photo isolator relays is further controlled in each channel switch using feedback from a resistor divider circuit to maintain the bus voltage swing within desired limits. Current sensing is provided using a switched resistive load in each channel switch, with switching of the resistive loads controlled from the central high voltage circuit.

Stamps, James Frederick (Livermore, CA); Crocker, Robert Ward (Fremont, CA); Yee, Daniel Dadwa (Dublin, CA); Dils, David Wright (Fort Worth, TX)

2008-03-25

56

Low power, scalable multichannel high voltage controller  

DOEpatents

A low voltage control circuit is provided for individually controlling high voltage power provided over bus lines to a multitude of interconnected loads. An example of a load is a drive for capillary channels in a microfluidic system. Control is distributed from a central high voltage circuit, rather than using a number of large expensive central high voltage circuits to enable reducing circuit size and cost. Voltage is distributed to each individual load and controlled using a number of high voltage controller channel switches connected to high voltage bus lines. The channel switches each include complementary pull up and pull down photo isolator relays with photo isolator switching controlled from the central high voltage circuit to provide a desired bus line voltage. Switching of the photo isolator relays is further controlled in each channel switch using feedback from a resistor divider circuit to maintain the bus voltage swing within desired limits. Current sensing is provided using a switched resistive load in each channel switch, with switching of the resistive loads controlled from the central high voltage circuit.

Stamps, James Frederick (Livermore, CA); Crocker, Robert Ward (Fremont, CA); Yee, Daniel Dadwa (Dublin, CA); Dils, David Wright (Fort Worth, TX)

2006-03-14

57

Adaptive Phase Adjustment Synchronization Method for Source Voltage Distortion in Electric Ship  

E-print Network

of connection with the nonlinear load. The SAPF consists of a voltage source inverter, current referenceAdaptive Phase Adjustment Synchronization Method for Source Voltage Distortion in Electric Ship, the source voltage typically contains some distortion. Specifically, US Navy ship power generators experience

Lehman, Brad

58

TOPEX electrical power system  

NASA Technical Reports Server (NTRS)

The TOPEX mission requirements which impact the power requirements and analyses are presented. A description of the electrical power system (EPS), including energy management and battery charging methods that were conceived and developed to meet the identified satellite requirements, is included. Analysis of the TOPEX EPS confirms that all of its electrical performance and reliability requirements have been met. The TOPEX EPS employs the flight-proven modular power system (MPS) which is part of the Multimission Modular Spacecraft and provides high reliability, abbreviated development effort and schedule, and low cost. An energy balance equation, unique to TOPEX, has been derived to confirm that the batteries will be completely recharged following each eclipse, under worst-case conditions. TOPEX uses three NASA Standard 50AH Ni-Cd batteries, each with 22 cells in series. The MPS contains battery charge control and protection based on measurements of battery currents, voltages, temperatures, and computed depth-of-discharge. In case of impending battery depletion, the MPS automatically implements load shedding.

Chetty, P. R. K.; Roufberg, Lew; Costogue, Ernest

1991-01-01

59

Magnetic power inverter: AC voltage generation from DC magnetic fields  

NASA Astrophysics Data System (ADS)

We propose a method that allows power conversion from DC magnetic fields to AC electric voltages using domain wall (DW) motion in ferromagnetic nanowires. The device concept relies on spinmotive force, voltage generation due to magnetization dynamics. Sinusoidal modulation of the nanowire width introduces a periodic potential for a DW, the gradient of which exerts variable pressure on the traveling DW. This results in time variation of the DW precession frequency and the associated voltage. Using a one-dimensional model, we show that the frequency and amplitude of the AC outputs can be tuned by the DC magnetic fields and wire-design.

Ieda, Jun'ichi; Maekawa, Sadamichi

2012-12-01

60

Programmable Multiple-Ramped-Voltage Power Supply  

NASA Technical Reports Server (NTRS)

Ramp waveforms range up to 2,000 V. Laboratory high-voltage power-supply system puts out variety of stable voltages programmed to remain fixed with respect to ground or float with respect to ramp waveform. Measures voltages it produces with high resolution; automatically calibrates, zeroes, and configures itself; and produces variety of input/output signals for use with other instruments. Developed for use with ultraviolet spectrometer. Also applicable to control of electron guns in general and to operation of such diverse equipment used in measuring scattering cross sections of subatomic particles and in industrial electron-beam welders.

Ajello, Joseph M.; Howell, S. K.

1993-01-01

61

Research and Design of High-Voltage Electronic Power Equipment Monitor System Based on Wireless Communication Technology  

Microsoft Academic Search

Temperature improvement of electronic power switchgear and handcart contact, as well as circuit breaker contact electrical arc erosion are easy to cause control action failure, trip, and power off, even more serious accident. So, it is a key to realize electric power system running through monitoring high-voltage equipment in real time. This paper design a kind of new high-voltage electric

Yu Chen; Haijun Zhang

2009-01-01

62

Designing nanosecond high voltage pulse generators using power MOSFETs  

E-print Network

Designing nanosecond high voltage pulse generators using power MOSFETs R.J. Baker and S.T. Ward Inde."'Cing terms: Power transistors, MOSFETs, Pulse generators, High-voltage engineering, High-voltage techniques, Power electronics Power MOSFETs in series are used for generating high voltage, >lkV, pulses

Baker, R. Jacob

63

Powering the electric car  

Microsoft Academic Search

The electric car may represent major new opportunities for America and its electric utilities. Widespread use of electric cars can reduce consumption of both imported and domestic oil, substituting abundant American fuels such as coal and nuclear power. Air and noise pollution can be reduced since emissions from a single power plant are easier to control than those from thousands

G. O. Murray; G. J. Ostrowski

1981-01-01

64

Oriented Engineering Application for Voltage Security Analysis of Power Systems  

Microsoft Academic Search

This paper deals with oriented engineering application of voltage security analysis of large-scale power systems, including engineering criterion of voltage security, principal objective, and systematic procedure of voltage security assessment. A systematic approach to voltage security assessment is presented in this paper. Example of Yunnan grid voltage security analysis using systematic voltage security analysis method is presented

Zhou Xia; Li Bi-jun; Li Wen-yun; Wu Chen; Xu Tai-shan; Ren Xian-cheng

2006-01-01

65

Local Dynamic Reactive Power for Correction of System Voltage Problems  

SciTech Connect

Distribution systems are experiencing outages due to a phenomenon known as local voltage collapse. Local voltage collapse is occurring in part because modern air conditioner compressor motors are much more susceptible to stalling during a voltage dip than older motors. These motors can stall in less than 3 cycles (.05s) when a fault, such as on the sub-transmission system, causes voltage to sag to 70 to 60%. The reasons for this susceptibility are discussed in the report. During the local voltage collapse, voltages are depressed for a period of perhaps one or two minutes. There is a concern that these local events are interacting together over larger areas and may present a challenge to system reliability. An effective method of preventing local voltage collapse is the use of voltage regulation from Distributed Energy Resources (DER) that can supply or absorb reactive power. DER, when properly controlled, can provide a rapid correction to voltage dips and prevent motor stall. This report discusses the phenomenon and causes of local voltage collapse as well as the control methodology we have developed to counter voltage sag. The problem is growing because of the use of low inertia, high efficiency air conditioner (A/C) compressor motors and because the use of electric A/C is growing in use and becoming a larger percentage of system load. A method for local dynamic voltage regulation is discussed which uses reactive power injection or absorption from local DER. This method is independent, rapid, and will not interfere with conventional utility system voltage control. The results of simulations of this method are provided. The method has also been tested at the ORNL s Distributed Energy Communications and Control (DECC) Laboratory using our research inverter and synchronous condenser. These systems at the DECC Lab are interconnected to an actual distribution system, the ORNL distribution system, which is fed from TVA s 161kV sub-transmission backbone. The test results are also provided and discussed. The simulations and testing show that local voltage control from DER can prevent local voltage collapse. The results also show that the control can be provided so quickly, within 0.5 seconds, that is does not interfere with conventional utility methods.

Kueck, John D [ORNL; Rizy, D Tom [ORNL; Li, Fangxing [ORNL; Xu, Yan [ORNL; Li, Huijuan [University of Tennessee, Knoxville (UTK); Adhikari, Sarina [ORNL; Irminger, Philip [ORNL

2008-12-01

66

Voltage Regulator Chip: Power Supplies on a Chip  

SciTech Connect

ADEPT Project: CPES at Virginia Tech is finding ways to save real estate on a computer's motherboard that could be used for other critical functions. Every computer processor today contains a voltage regulator that automatically maintains a constant level of electricity entering the device. These regulators contain bulky components and take up about 30% of a computer's motherboard. CPES at Virginia Tech is developing a voltage regulator that uses semiconductors made of gallium nitride on silicon (GaN-on-Si) and high-frequency soft magnetic material. These materials are integrated on a small, 3D chip that can handle the same amount of power as traditional voltage regulators at 1/10 the size and with improved efficiency. The small size also frees up to 90% of the motherboard space occupied by current voltage regulators.

None

2010-09-01

67

High voltage bus and auxiliary heater control system for an electric or hybrid vehicle  

DOEpatents

A control system for an electric or hybrid electric vehicle includes a vehicle system controller and a control circuit having an electric immersion heater. The heater is electrically connected to the vehicle's high voltage bus and is thermally coupled to a coolant loop containing a heater core for the vehicle's climate control system. The system controller responds to cabin heat requests from the climate control system by generating a pulse width modulated signal that is used by the control circuit to operate the heater at a duty cycle appropriate for the amount of cabin heating requested. The control system also uses the heater to dissipate excess energy produced by an auxiliary power unit and to provide electric braking when regenerative braking is not desirable and manual braking is not necessary. The control system further utilizes the heater to provide a safe discharge of a bank of energy storage capacitors following disconnection of the battery or one of the high voltage connectors used to transmit high voltage operating power to the various vehicle systems. The control circuit includes a high voltage clamping circuit that monitors the voltage on the bus and operates the heater to clamp down the bus voltage when it exceeds a pre-selected maximum voltage. The control system can also be used to phase in operation of the heater when the bus voltage exceeds a lower threshold voltage and can be used to phase out the auxiliary power unit charging and regenerative braking when the battery becomes fully charged.

Murty, Balarama Vempaty (West Bloomfield, MI)

2000-01-01

68

Modular High-Voltage Power Supplies design  

Microsoft Academic Search

Modular High Voltage Power Supplies (HVPS) have crucial advantages over one-module HVPS. The article is devoted to a new patented HVPS technology. The new method of HV generation creates new possibilities for advanced HVPS performance. New design makes HVPS much smaller and lighter. HVPS reliability is enhanced. Manufacturing cost is close to the cost of conventional HVPS. The HVPS consists

I. A. Krichtafovitch

1997-01-01

69

A converter topology to interface low voltage Solar\\/Fuel Cell type energy sources to electric utility  

Microsoft Academic Search

Solar and fuel cells are some of the most promising energy sources for future energy generation. However due to their variable and low magnitude voltage a power conditioner capable of providing a large voltage gain is required. This is especially true in applications supplying power to AC loads or the electric grid in which a voltage gain around 8 p.u.

L. Palma; P. Enjeti; N. Denniston; J. L. Duran-Gomez

2008-01-01

70

Evaluation of high-voltage, high-power, solid-state remote power controllers for amps  

NASA Astrophysics Data System (ADS)

The Electrical Power Branch at Marshall Space Flight Center has a Power System Development Facility where various power circuit breadboards are tested and evaluated. This project relates to the evaluation of a particular remote power controller (RPC) energizing high power loads. The Facility equipment permits the thorough testing and evaluation of high-voltage, high-power solid-state remote power controllers. The purpose is to evaluate a Type E, 30 Ampere, 200 V dc remote power controller. Three phases of the RPC evaluation are presented. The RPC is evaluated within a low-voltage, low-power circuit to check its operational capability. The RPC is then evaluated while performing switch/circuit breaker functions within a 200 V dc, 30 Ampere power circuit. The final effort of the project relates to the recommended procedures for installing these RPC's into the existing Autonomously Managed Power System (AMPS) breadboard/test facility at MSFC.

Callis, Charles P.

1987-11-01

71

Evaluation of high-voltage, high-power, solid-state remote power controllers for amps  

NASA Technical Reports Server (NTRS)

The Electrical Power Branch at Marshall Space Flight Center has a Power System Development Facility where various power circuit breadboards are tested and evaluated. This project relates to the evaluation of a particular remote power controller (RPC) energizing high power loads. The Facility equipment permits the thorough testing and evaluation of high-voltage, high-power solid-state remote power controllers. The purpose is to evaluate a Type E, 30 Ampere, 200 V dc remote power controller. Three phases of the RPC evaluation are presented. The RPC is evaluated within a low-voltage, low-power circuit to check its operational capability. The RPC is then evaluated while performing switch/circuit breaker functions within a 200 V dc, 30 Ampere power circuit. The final effort of the project relates to the recommended procedures for installing these RPC's into the existing Autonomously Managed Power System (AMPS) breadboard/test facility at MSFC.

Callis, Charles P.

1987-01-01

72

Bi-directional power control system for voltage converter  

DOEpatents

A control system for a voltage converter includes: a power comparator for comparing a power signal on input terminals of the converter with a commanded power signal and producing a power comparison signal; a power regulator for transforming the power comparison signal to a commanded current signal; a current comparator for comparing the commanded current signal with a measured current signal on output terminals of the converter and producing a current comparison signal; a current regulator for transforming the current comparison signal to a pulse width modulator (PWM) duty cycle command signal; and a PWM for using the PWM duty cycle command signal to control electrical switches of the converter. The control system may further include: a command multiplier for converting a voltage signal across the output terminals of the converter to a gain signal having a value between zero (0) and unity (1), and a power multiplier for multiplying the commanded power signal by the gain signal to provide a limited commanded power signal, wherein power comparator compares the limited commanded power signal with the power signal on the input terminals. 10 figs.

Garrigan, N.R.; King, R.D.; Schwartz, J.E.

1999-05-11

73

Bi-directional power control system for voltage converter  

DOEpatents

A control system for a voltage converter includes: a power comparator for comparing a power signal on input terminals of the converter with a commanded power signal and producing a power comparison signal; a power regulator for transforming the power comparison signal to a commanded current signal; a current comparator for comparing the commanded current signal with a measured current signal on output terminals of the converter and producing a current comparison signal; a current regulator for transforming the current comparison signal to a pulse width modulator (PWM) duty cycle command signal; and a PWM for using the PWM duty cycle command signal to control electrical switches of the converter. The control system may further include: a command multiplier for converting a voltage signal across the output terminals of the converter to a gain signal having a value between zero (0) and unity (1), and a power multiplier for multiplying the commanded power signal by the gain signal to provide a limited commanded power signal, wherein power comparator compares the limited commanded power signal with the power signal on the input terminals.

Garrigan, Neil Richard (Niskayuna, NY); King, Robert Dean (Schenectady, NY); Schwartz, James Edward (Slingerlands, NY)

1999-01-01

74

Electric power annual 1992  

SciTech Connect

The Electric Power Annual presents a summary of electric utility statistics at national, regional and State levels. The objective of the publication is to provide industry decisionmakers, government policymakers, analysts and the general public with historical data that may be used in understanding US electricity markets. The Electric Power Annual is prepared by the Survey Management Division; Office of Coal, Nuclear, Electric and Alternate Fuels; Energy Information Administration (EIA); US Department of Energy. ``The US Electric Power Industry at a Glance`` section presents a profile of the electric power industry ownership and performance, and a review of key statistics for the year. Subsequent sections present data on generating capability, including proposed capability additions; net generation; fossil-fuel statistics; retail sales; revenue; financial statistics; environmental statistics; electric power transactions; demand-side management; and nonutility power producers. In addition, the appendices provide supplemental data on major disturbances and unusual occurrences in US electricity power systems. Each section contains related text and tables and refers the reader to the appropriate publication that contains more detailed data on the subject matter. Monetary values in this publication are expressed in nominal terms.

Not Available

1994-01-06

75

Contract networks for electric power transmission  

Microsoft Academic Search

A contract network extends the concept of a contract path to address the problem of loop flow and congestion in electric power transmission systems. A contract network option provides an internally consistent framework for assigning long-term capacity rights to a complicated electric transmission network. The contract network respects the special conditions induced by Kirchoff's Laws; accommodates thermal, voltage, and contingency

William W. Hogan

1992-01-01

76

Second Edition Electric Power  

E-print Network

Monterrey #12;#12;iGUIDE TO ELECTRIC POWER IN MEXICO TABLE OF CONTENTS Part 1 Facts on Mexico Electric Power, an emeritus professor at the Instituto Tecnológico y de Estudios Superiores de Monterrey (ITESM), now retired

Texas at Austin, University of

77

Modular high voltage power supply for chemical analysis  

DOEpatents

A high voltage power supply for use in a system such as a microfluidics system, uses a DC--DC converter in parallel with a voltage-controlled resistor. A feedback circuit provides a control signal for the DC--DC converter and voltage-controlled resistor so as to regulate the output voltage of the high voltage power supply, as well as, to sink or source current from the high voltage supply.

Stamps, James F. (Livermore, CA); Yee, Daniel D. (Dublin, CA)

2007-01-09

78

Modular high voltage power supply for chemical analysis  

DOEpatents

A high voltage power supply for use in a system such as a microfluidics system, uses a DC-DC converter in parallel with a voltage-controlled resistor. A feedback circuit provides a control signal for the DC-DC converter and voltage-controlled resistor so as to regulate the output voltage of the high voltage power supply, as well as, to sink or source current from the high voltage supply.

Stamps, James F. (Livermore, CA); Yee, Daniel D. (Dublin, CA)

2008-07-15

79

Modular high voltage power supply for chemical analysis  

DOEpatents

A high voltage power supply for use in a system such as a microfluidics system, uses a DC-DC converter in parallel with a voltage-controlled resistor. A feedback circuit provides a control signal for the DC-DC converter and voltage-controlled resistor so as to regulate the output voltage of the high voltage power supply, as well as, to sink or source current from the high voltage supply.

Stamps, James F. (Livermore, CA); Yee, Daniel D. (Dublin, CA)

2010-05-04

80

Wavelet-based dynamic voltage restorer for power quality improvement  

Microsoft Academic Search

This paper presents a novel method for power quality improvement employing wavelet analysis. A wavelet filter bank is used to detect and classify various disturbances experienced by the voltage on the load side. A dynamic voltage restorer is used to compensate the voltage under disturbance conditions and maintain the rated load voltage. The input and the output voltages of the

S. A. Saleh; M. A. Rahman

2004-01-01

81

Power quality issues with adjustable frequency drives -- Coping with power loss and voltage transient occurrences  

SciTech Connect

The power quality issue is not new to consumers of electrical power. From individual home owners to large industrial complexes, power quality problems can cause eyebrows to raise or bring industrial giants to their knees. Power quality comes in many forms. It can appear in the form of a voltage source which decreases to a small fraction of its normal strength or as a voltage transient, briefly far exceeding its normal value, ready to break down electrical insulation. It can appear as an oscillating voltage or a traveling voltage wave beating against barriers designed as added protection. Defining a single set of rules to control the characteristics of power quality is difficult, since its impact on electrical equipment changes as the characteristics of equipment change. A key to understanding how to cope with power quality issues begins with understanding the nature of electrical products. The nature of any product is defined by how its components are selected and how the designers apply those components. Reviewing design criteria, component selection and product characteristics can provide this basis of understanding.

Murphy, H.G. (Allen-Bradley Co., Mequon, WI (United States))

1993-07-01

82

Electric power annual 1993  

SciTech Connect

This report presents a summary of electric power industry statistics at national, regional, and state levels: generating capability and additions, net generation, fossil-fuel statistics, retail sales and revenue, finanical statistics, environmental statistics, power transactions, demand side management, nonutility power producers. Purpose is to provide industry decisionmakers, government policymakers, analysts, and the public with historical data that may be used in understanding US electricity markets.

Not Available

1994-12-08

83

A novel power converter of high voltage switched reluctance drive  

Microsoft Academic Search

Due to the lack of withstand voltage of power electronic devices, and the voltage equalization among devices is hard to achieve when cascading the devices directly, the development of high-voltage switched reluctance drive has been blocked. Therefore, this paper proposes a novel high-voltage switched reluctance drive power converter structured by low-voltage power electronic devices. It introduces the composition and principles

Runquan Meng; Yi Yang

2011-01-01

84

Generator voltage stabilisation for series-hybrid electric vehicles.  

PubMed

This paper presents a controller for use in speed control of an internal combustion engine for series-hybrid electric vehicle applications. Particular reference is made to the stability of the rectified DC link voltage under load disturbance. In the system under consideration, the primary power source is a four-cylinder normally aspirated gasoline internal combustion engine, which is mechanically coupled to a three-phase permanent magnet AC generator. The generated AC voltage is subsequently rectified to supply a lead-acid battery, and permanent magnet traction motors via three-phase full bridge power electronic inverters. Two complementary performance objectives exist. Firstly to maintain the internal combustion engine at its optimal operating point, and secondly to supply a stable 42 V supply to the traction drive inverters. Achievement of these goals minimises the transient energy storage requirements at the DC link, with a consequent reduction in both weight and cost. These objectives imply constant velocity operation of the internal combustion engine under external load disturbances and changes in both operating conditions and vehicle speed set-points. An electronically operated throttle allows closed loop engine velocity control. System time delays and nonlinearities render closed loop control design extremely problematic. A model-based controller is designed and shown to be effective in controlling the DC link voltage, resulting in the well-conditioned operation of the hybrid vehicle. PMID:18262528

Stewart, P; Gladwin, D; Stewart, J; Cowley, R

2008-04-01

85

No energy stored power conditioners for voltage sag compensation  

Microsoft Academic Search

Voltage sags can be compensated at low voltage level through using no-energy stored voltage conditioners based on power electronic components. Different compensation principles and power semiconductor devices (SCRs, GTOs, IGBTs) can be used, with different expected performances. This paper illustrates the advantages offered in voltage sag compensation by conditioners based on high switching frequency components and underlines the need for

A. Boscolo; S. Quaia; F. Tosato

1998-01-01

86

High Voltage Power Supply Design Guide for Space  

NASA Technical Reports Server (NTRS)

This book is written for newcomers to the topic of high voltage (HV) in space and is intended to replace an earlier (1970s) out-of-print document. It discusses the designs, problems, and their solutions for HV, mostly direct current, electric power, or bias supplies that are needed for space scientific instruments and devices, including stepping supplies. Output voltages up to 30kV are considered, but only very low output currents, on the order of microamperes. The book gives a brief review of the basic physics of electrical insulation and breakdown problems, especially in gases. It recites details about embedment and coating of the supplies with polymeric resins. Suggestions on HV circuit parts follow. Corona or partial discharge testing on the HV parts and assemblies is discussed both under AC and DC impressed test voltages. Electric field analysis by computer on an HV device is included in considerable detail. Finally, there are many examples given of HV power supplies, complete with some of the circuit diagrams and color photographs of the layouts.

Bever, Renate S.; Ruitberg, Arthur P.; Kellenbenz, Carl W.; Irish, Sandra M.

2006-01-01

87

High voltage power condition systems powered by flux compression generators  

Microsoft Academic Search

Compact, high-gain magnetic flux compressors (FCGs) are convenient sources of substantial energy for plasma-physics and electron-beam-physics experiments, but the need for high-voltage, fast-rising pulses is difficult to meet directly with conventional generators. While a variety of novel concepts employing simultaneous, axially-detonated explosive systems are under development, power-conditioning systems based on fuse opening switches and high-voltage transformers constitute another approach that

R. E. Reinovsky; I. R. Lindemuth; J. E. Vorthman

1989-01-01

88

Reduced voltage sensitivity in a K+-channel voltage sensor by electric field remodeling  

PubMed Central

Propagation of the nerve impulse relies on the extreme voltage sensitivity of Na+ and K+ channels. The transmembrane movement of four arginine residues, located at the fourth transmembrane segment (S4), in each of their four voltage-sensing domains is mostly responsible for the translocation of 12 to 13 eo across the transmembrane electric field. Inserting additional positively charged residues between the voltage-sensing arginines in S4 would, in principle, increase voltage sensitivity. Here we show that either positively or negatively charged residues added between the two most external sensing arginines of S4 decreased voltage sensitivity of a Shaker voltage-gated K+-channel by up to ?50%. The replacement of Val363 with a charged residue displaced inwardly the external boundaries of the electric field by at least 6 Å, leaving the most external arginine of S4 constitutively exposed to the extracellular space and permanently excluded from the electric field. Both the physical trajectory of S4 and its electromechanical coupling to open the pore gate seemed unchanged. We propose that the separation between the first two sensing charges at resting is comparable to the thickness of the low dielectric transmembrane barrier they must cross. Thus, at most a single sensing arginine side chain could be found within the field. The conserved hydrophobic nature of the residues located between the voltage-sensing arginines in S4 may shape the electric field geometry for optimal voltage sensitivity in voltage-gated ion channels. PMID:20194763

González-Pérez, Vivian; Stack, Katherine; Boric, Katica; Naranjo, David

2010-01-01

89

Advanced electric propulsion system concept for electric vehicles. Addendum 1: Voltage considerations  

NASA Technical Reports Server (NTRS)

The two electric vehicle propulsion systems that best met cost and performance goals were examined to assess the effect of battery pack voltage on system performance and cost. A voltage range of 54 to 540 V was considered for a typical battery pack capacity of 24 k W-hr. The highest battery specific energy (W-hr/kg) and the lowest cost ($/kW-hr) were obtained at the minimum voltage level. The flywheel system traction motor is a dc, mechanically commutated with shunt field control, and due to the flywheel the traction motor and the battery are not subject to extreme peaks of power demand. The basic system uses a permanent-magnet motor with electronic commutation supplied by an ac power control unit. In both systems battery cost were the major factor in system voltage selection, and a battery pack with the minimum voltage of 54 V produced the lowest life-cycle cost. The minimum life-cycle cost for the basic system with lead-acid batteries was $0.057/km and for the flywheel system was $0.037/km.

Raynard, A. E.; Forbes, F. E.

1980-01-01

90

Programmable high voltage power supply with regulation confined to the high voltage section  

Microsoft Academic Search

A high voltage power supply in a dc-dc converter configuration includes a pre-regulator which filters and regulates the dc input and drives an oscillator which applies, in turn, a low voltage ac signal to the low side of a step-up high voltage transformer. The high voltage side of the transformer drives a voltage multiplier which provides a stepped up dc

Karen D. Castell; Arthur P. Ruitberg

1994-01-01

91

Electric power monthly  

SciTech Connect

The Energy Information Administration (EIA) prepares the Electric Power Monthly (EPM) for a wide audience including Congress, Federal and State agencies, the electric utility industry, and the general public. This publication provides monthly statistics for net generation, fossil fuel consumption and stocks, quantity and quality of fossil fuels, cost of fossil fuels, electricity sales, revenue, and average revenue per kilowatthour of electricity sold. Data on net generation, fuel consumption, fuel stocks, quantity and cost of fossil fuels are also displayed for the North American Electric Reliability Council (NERC) regions. The EIA publishes statistics in the EPM on net generation by energy source, consumption, stocks, quantity, quality, and cost of fossil fuels; and capability of new generating units by company and plant. The purpose of this publication is to provide energy decisionmakers with accurate and timely information that may be used in forming various perspectives on electric issues that lie ahead.

NONE

1995-08-01

92

A high voltage power supply for the AE-C and D low energy electron experiment  

NASA Technical Reports Server (NTRS)

A description is given of the electrical and mechanical design and operation of high voltage power supplies for space flight use. The supply was used to generate the spiraltron high voltage for low energy electron experiment on AE-C and D. Two versions of the supply were designed and built; one design is referred to as the low power version (AE-C) and the other as the high power version (AE-D). Performance is discussed under all operating conditions.

Gillis, J. A.

1974-01-01

93

Recent Advances in High-Voltage Direct-Current Power Transmission Systems  

Microsoft Academic Search

The ever increasing progress of high-voltage high-power fully-controlled semiconductor technology continues to have a significant impact on the development of advanced power electronic apparatus used to support optimised operations and efficient management of electrical grids, which in many cases, are fully or partially deregulated networks. Developments advance both the high-voltage direct-current (HVDC) power transmission and the flexible alternating current transmission

Vassilios G. Agelidis; Georgios D. Demetriades; Nikolas Flourentzou

2006-01-01

94

High voltage pulse power implementation using IGBT stacks  

Microsoft Academic Search

High voltage pulse power implementation using IGBT stacks is proposed in this paper. High voltage pulse power implementation uses Marx circuit as the main circuit. The Marx circuit is composed of 12 stages and each stage is made of IGBT stack, two diode stacks, and capacitor. Diode stacks and inductor are used to charge high voltage capacitor of each stage

Jong-Hyun Kim; Myung-Hyo Ryu; Byung-Duk Min; Ju-Won Baek; Jong-Soo Kim; Geun-Hie Rim

2006-01-01

95

Design and power management of an offshore medium voltage DC microgrid realized through high voltage power electronics technologies and control  

NASA Astrophysics Data System (ADS)

The growth in the electric power industry's portfolio of Direct Current (DC) based generation and loads have captured the attention of many leading research institutions. Opportunities for using DC based systems have been explored in electric ship design and have been a proven, reliable solution for transmitting bulk power onshore and offshore. To integrate many of the renewable resources into our existing AC grid, a number of power conversions through power electronics are required to condition the equipment for direct connection. Within the power conversion stages, there is always a requirement to convert to or from DC. The AC microgrid is a conceptual solution proposed for integrating various types of renewable generation resources. The fundamental microgrid requirements include the capability of operating in islanding mode and/or grid connected modes. The technical challenges associated with microgrids include (1) operation modes and transitions that comply with IEEE1547 without extensive custom engineering and (2) control architecture and communication. The Medium Voltage DC (MVDC) architecture, explored by the University of Pittsburgh, can be visualized as a special type of DC microgrid. This dissertation is multi-faceted, focused on many design aspects of an offshore DC microgrid. The focal points of the discussion are focused on optimized high power, high frequency magnetic material performance in electric machines, transformers, and DC/DC power converters---all components found within offshore, power system architectures. A new controller design based upon model reference control is proposed and shown to stabilize the electric motor drives (modeled as constant power loads), which serve as the largest power consuming entities in the microgrid. The design and simulation of a state-of-the-art multilevel converter for High Voltage DC (HVDC) is discussed and a component sensitivity analysis on fault current peaks is explored. A power management routine is proposed and evaluated as the DC microgrid is disturbed through various mode transitions. Finally, two communication protocols are described for the microgrid---one to minimize communication overhead inside the microgrid and another to provide robust and scalable intra-grid communication. The work presented is supported by Asea Brown Boveri (ABB) Corporate Research Center within the Active Grid Infrastructure program, the Advanced Research Project Agency - Energy (ARPA-E) through the Solar ADEPT program, and Mitsubishi Electric Corporation (MELCO).

Grainger, Brandon Michael

96

A Novel Series Connected Batteries State of High Voltage Safety Monitor System for Electric Vehicle Application  

PubMed Central

Batteries, as the main or assistant power source of EV (Electric Vehicle), are usually connected in series with high voltage to improve the drivability and energy efficiency. Today, more and more batteries are connected in series with high voltage, if there is any fault in high voltage system (HVS), the consequence is serious and dangerous. Therefore, it is necessary to monitor the electric parameters of HVS to ensure the high voltage safety and protect personal safety. In this study, a high voltage safety monitor system is developed to solve this critical issue. Four key electric parameters including precharge, contact resistance, insulation resistance, and remaining capacity are monitored and analyzed based on the equivalent models presented in this study. The high voltage safety controller which integrates the equivalent models and control strategy is developed. By the help of hardware-in-loop system, the equivalent models integrated in the high voltage safety controller are validated, and the online electric parameters monitor strategy is analyzed and discussed. The test results indicate that the high voltage safety monitor system designed in this paper is suitable for EV application. PMID:24194677

Jiaxi, Qiang; Lin, Yang; Jianhui, He; Qisheng, Zhou

2013-01-01

97

Electric Power Annual  

EIA Publications

Presents 11 years (2003 - 2013) of national-level data on electricity generating capacity, electricity generation and useful thermal output, fuel receipts, consumption, and emissions. This year's Electric Power Annual has expanded to include several new table series. These include several new annual breakouts of renewable biomass energy sources including wood/wood waste, landfill gas, and biogenic municipal solid waste in Chapter 5 (Consumption of Fossil Fuels); state details of emissions from energy consumption at conventional power plants and combined-heat-and-power plants (Table 9.5); and monthly capacity factors for the past three years and annual capacity factors back to 2008 (Tables 4.8.A. and 4.8.B.)

2015-01-01

98

Power plant and method of production of synchronous commercial electric power using diesel electric locomotives  

SciTech Connect

This patent describes a method of producing synchronous electric power at utility transmission or subtransmission voltages to an electric utility grid during periods of peak electrical demand. It comprises providing at least two conventional diesel electric railroad locomotives, each having a diesel engine with a speed governor for such engine, an electrical generator driven by the engine, electrical drive motors driven from electricity provided by the generator, railroad wheels on axles driven by the drive motors, positioning the locomotives stationary at a location on railroad tracks, disconnecting the electric drive motors of the locomotives from the locomotive generator, connecting the output of the locomotive generators in parallel to generate synchronous electric power, controlling the speed of the diesel engines within the tolerances required for synchronous alternating current generation, and connecting the electrical output of the locomotive generators to step up transformer means and to an electric utility distribution grid.

Jenkins, C.P.

1991-11-19

99

Pattern recognition for electric power system protection  

Microsoft Academic Search

The objective of this research is to demonstrate pattern recognition tools such as decision trees (DTs) and neural networks that will improve and automate the design of relay protection functions in electric power systems. Protection functions that will benefit from the research include relay algorithms for high voltage transformer protection (TP) and for high impedance fault (HIF) detection. A methodology,

Yong Sheng

2002-01-01

100

Electric power monthly  

SciTech Connect

The Electric Power Monthly is prepared by the Survey Management Division; Office of Coal, Nuclear, Electric and Alternate Fuels, Energy Information Administration (EIA), Department of Energy. This publication provides monthly statistics at the national, Census division, and State levels for net generation, fuel consumption, fuel stocks, quantity and quality of fuel, cost of fuel, electricity sales, revenue, and average revenue per kilowatthour of electricity sold. Data on net generation, fuel consumption, fuel stocks, quantity and cost of fuel are also displayed for the North American Electric Reliability Council (NERC) regions. Additionally, statistics by company and plant are published in the EPM on capability of new plants, new generation, fuel consumption, fuel stocks, quantity and quality of fuel, and cost of fuel.

Not Available

1992-05-01

101

Various Considerations for Estimating Steady-State Voltage Drop in Low Voltage AC Power Distribution Systems  

Microsoft Academic Search

This paper provides a simplified approach on various considerations to estimate the steady-state voltage drop in low voltage AC power distribution systems. Apart from other parameters, 'load center distance' is critical in most of the cases to determine realistically the voltage drop. This aspect is therefore covered in detail by developing equations to compute the load center distance for various

Shanmuga S. Pandian; A. Al-Saihati; A. Fattani; O. Al-Othman

2006-01-01

102

The advantages of the high voltage solar array for electric propulsion  

NASA Technical Reports Server (NTRS)

The high voltage solar array offers improvements in efficiency, weight, and reliability for the electric propulsion power system. Conventional power processes and problems associated with ion thruster operation using SERT 2 experience are discussed and the advantages of the HVSA concept for electric propulsion are presented. Tests conducted operating the SERT 2 thruster system in conjunction with HVSA are reported. Thruster operation was observed to be normal and in some respects improved.

Sater, B. L.

1973-01-01

103

Innovative concepts for power station design in all electric ships  

Microsoft Academic Search

The paper points out innovative design issues of the shipboard power stations for all electric ships (AESs). Alternators and voltage control system operations are reviewed under an approach which emphasizes the impact of design choices on power generation and availability. The work moves from an in-deep analysis of modern cruise ship integrated electric power systems (IEPSs), in order to assess

A. Da Rin; S. Quaia; G. Sulligoi

2008-01-01

104

High frequency AC power converter for low voltage circuits  

E-print Network

This thesis presents a novel AC power delivery architecture that is suitable for VHF frequency (50-100MHz) polyphase AC/DC power conversion in low voltage integrated circuits. A complete AC power delivery architecture was ...

Salazar, Nathaniel Jay Tobias

2012-01-01

105

High voltage electric substation performance in earthquakes  

SciTech Connect

This paper examines the performance of several types of high voltage substation equipment in past earthquakes. Damage data is provided in chart form. This data is then developed into a tool for estimating the performance of a substation subjected to an earthquake. First, suggests are made about the development of equipment class fragility curves that represent the expected earthquake performance of different voltages and types of equipment. Second, suggestions are made about how damage to individual pieces of equipment at a substation likely affects the post-earthquake performance of the substation as a whole. Finally, estimates are provided as to how quickly a substation, at various levels of damage, can be restored to operational service after the earthquake.

Eidinger, J. [G and E Engineering Systems, Oakland, CA (United States); Ostrom, D. [Southern California Edison, Rosemead, CA (United States); Matsuda, E. [Pacific Gas and Electric, San Francisco, CA (United States)

1995-12-31

106

Electricity Today30 American Electric Power, working  

E-print Network

efficiency, environ- mental optimization and national security for the benefit of electric customers across system is currently inadequate to deliver energy from remote wind resource areas to electrical loadElectricity Today30 American Electric Power, working at the request of, and in partnership with

Laughlin, Robert B.

107

Monitoring and control of voltage stability in power systems  

SciTech Connect

This paper proposes a new technique in controlling voltage instability in power systems. This technique coordinates between the reactive power of excitation systems and that of static var compensators (SVCs). The method starts with the decomposition of system into several voltage control areas (VCAs). When a reactive power deficiency occurs in certain area, excitation systems respond first to supply the required reactive power by increasing reactive generation of synchronous generators to its upper limit. If more reactive power is needed within the specific area to recover voltage instability, a SVC will be inserted by a switching controller in order to achieve the reactive balance. This controller receives an actuating signal when the terminal voltage is still unsatisfactory. By this technique, it is possible to fully utilize the excitation systems reactive power, and to design economic size SVCs to recover voltage instability. The application of the proposed technique on the New-England 39 bus system proves its efficiency in controlling voltage instability.

Sallam, A.A.; Aboul-Ela, M.E.; Elaraby, E.E. [Suez Canal Univ., Port-Said (Egypt)

1995-12-31

108

Programmable high voltage power supply with regulation confined to the high voltage section  

NASA Technical Reports Server (NTRS)

A high voltage power supply in a dc-dc converter configuration includes a pre-regulator which filters and regulates the dc input and drives an oscillator which applies, in turn, a low voltage ac signal to the low side of a step-up high voltage transformer. The high voltage side of the transformer drives a voltage multiplier which provides a stepped up dc voltage to an output filter. The output voltage is sensed by a feedback network which then controls a regulator. Both the input and output of the regulator are on the high voltage side, avoiding isolation problems. The regulator furnishes a portion of the drive to the voltage multiplier, avoiding having a regulator in series with the load with its attendant, relatively high power losses. This power supply is highly regulated, has low power consumption, a low parts count and may be manufactured at low cost. The power supply has a programmability feature that allows for the selection of a large range of output voltages.

Castell, Karen D. (inventor); Ruitberg, Arthur P. (inventor)

1994-01-01

109

A low-power design method using multiple supply voltages  

Microsoft Academic Search

We present a low-power design method that utilizes the multiple supply voltages. The proposed method reduces the power consumption of random logic circuits by 47% on the average, with up to 15% area overhead, by the combination of “clustered Voltage Scaling (CVS) scheme” and “Bow by Row optimized Power &pply (RRPS) scheme”. By the CVS scheme, the optimal netlist, that

Mutsunori Igarashi; Kimiyoshi Usami; Kazutaka Nogami; Fumihiro Minami; Yukio Kawasaki; Takahiro Aoki; Midori Takano; Chiharo Mizuno; Takashi Ishikawa; Masahiro Kanazawa; Shinji Sonoda; Makoto Ichida; Naoyuki Hatanaka

1997-01-01

110

US electric power system reliability  

NASA Astrophysics Data System (ADS)

Electric energy supply, transmission and distribution systems are investigated in order to determine priorities for legislation. The status and the outlook for electric power reliability are discussed.

111

High voltage power condition systems powered by flux compression generators  

Microsoft Academic Search

Compact, high-gain magnetic flux compressors (FCGs) are convenient sources of substantial energy for plasma-physics and electron-beam-physics experiments, but the need for highvoltage, fast-rising pulses is difficult to meet directly with conventional generators. While a variety of novel concepts employing simultaneous, axially-detonated explosive systems are under development, power-conditioning systems based on fuse opening switches and high-voltage transformers constitute an approach that

R. E. Reinovsky; I. R. Lindemuth; J. E. Vorthman

1989-01-01

112

The design, construction, and operation of long-distance high-voltage electricity transmission technologies.  

SciTech Connect

This report focuses on transmission lines, which operate at voltages of 115 kV and higher. Currently, the highest voltage lines comprising the North American power grid are at 765 kV. The grid is the network of transmission lines that interconnect most large power plants on the North American continent. One transmission line at this high voltage was built near Chicago as part of the interconnection for three large nuclear power plants southwest of the city. Lines at this voltage also serve markets in New York and New England, also very high demand regions. The large power transfers along the West Coast are generally at 230 or 500 kV. Just as there are practical limits to centralization of power production, there are practical limits to increasing line voltage. As voltage increases, the height of the supporting towers, the size of the insulators, the distance between conductors on a tower, and even the width of the right-of-way (ROW) required increase. These design features safely isolate the electric power, which has an increasing tendency to arc to ground as the voltage (or electrical potential) increases. In addition, very high voltages (345 kV and above) are subject to corona losses. These losses are a result of ionization of the atmosphere, and can amount to several megawatts of wasted power. Furthermore, they are a local nuisance to radio transmission and can produce a noticeable hum. Centralized power production has advantages of economies of scale and special resource availability (for instance, hydro resources), but centralized power requires long-distance transfers of power both to reach customers and to provide interconnections for reliability. Long distances are most economically served at high voltages, which require large-scale equipment and impose a substantial footprint on the corridors through which power passes. The most visible components of the transmission system are the conductors that provide paths for the power and the towers that keep these conductors at a safe distance from each other and from the ground and the natural and built environment. Common elements that are generally less visible (or at least more easily overlooked) include the maintained ROW along the path of the towers, access roads needed for maintenance, and staging areas used for initial construction that may be restored after construction is complete. Also visible but less common elements along the corridor may include switching stations or substations, where lines of similar or different voltages meet to transfer power.

Molburg, J. C.; Kavicky, J. A.; Picel, K. C.

2008-03-03

113

Improved detection of electrical activity with a voltage probe based on a voltage-sensing phosphatase  

PubMed Central

One of the most awaited techniques in modern physiology is the sensitive detection of spatiotemporal electrical activity in a complex network of excitable cells. The use of genetically encoded voltage probes has been expected to enable such analysis. However, in spite of recent progress, existing probes still suffer from low signal amplitude and/or kinetics too slow to detect fast electrical activity. Here, we have developed an improved voltage probe named Mermaid2, which is based on the voltage-sensor domain of the voltage-sensing phosphatase from Ciona intestinalis and Förster energy transfer between a pair of fluorescent proteins. In mammalian cells, Mermaid2 permits ratiometric readouts of fractional changes of more than 50% over a physiologically relevant voltage range with fast kinetics, and it was used to follow a train of action potentials at frequencies of up to 150 Hz. Mermaid2 was also able to detect single action potentials and subthreshold voltage responses in hippocampal neurons in vitro, in addition to cortical electrical activity evoked by sound stimuli in single trials in living mice. PMID:23836686

Tsutsui, Hidekazu; Jinno, Yuka; Tomita, Akiko; Niino, Yusuke; Yamada, Yoshiyuki; Mikoshiba, Katsuhiko; Miyawaki, Atsushi; Okamura, Yasushi

2013-01-01

114

High voltage vacuum insulation in crossed magnetic and electric fields  

Microsoft Academic Search

This work discusses research on high-voltage vacuum insulation conducted using several test stands to support development of an improved electrostatic deflector for the Chalk River superconducting cyclotron. One test stand uses a magnetic field of 0.5 T normal to the electric field. It is instrumented with isolated electrodes above and below the negative high-voltage electrode, an isolated anode and monitors

W. T. Diamond

1993-01-01

115

Measuring Helical FCG Voltage with an Electric Field Antenna  

SciTech Connect

A method of measuring the voltage produced by a helical explosive flux compression generator using a remote electric field antenna is described in detail. The diagnostic has been successfully implemented on several experiments. Measured data from the diagnostic compare favorably with voltages predicted using the code CAGEN, validating our predictive modeling tools. The measured data is important to understanding generator performance, and is measured with a low-risk, minimally intrusive approach.

White, A D; Anderson, R A; Javedani, J B; Reisman, D B; Goerz, D A; Ferriera, A J; Speer, R D

2011-08-01

116

E-beam high voltage switching power supply  

DOEpatents

A high-power power supply produces a controllable, constant high voltage put under varying and arcing loads. The power supply includes a voltage regulator, an inductor, an inverter for producing a high frequency square wave current of alternating polarity, an improved inverter voltage clamping circuit, a step up transformer, an output rectifier for producing a dc voltage at the output of each module, and a current sensor for sensing output current. The power supply also provides dynamic response to varying loads by controlling the voltage regulator duty cycle and circuitry is provided for sensing incipient arc currents at the output of the power supply to simultaneously decouple the power supply circuitry from the arcing load. The power supply includes a plurality of discrete switching type dc--dc converter modules.

Shimer, Daniel W. (Danville, CA); Lange, Arnold C. (Livermore, CA)

1996-01-01

117

E-beam high voltage switching power supply  

DOEpatents

A high-power power supply produces a controllable, constant high voltage output under varying and arcing loads. The power supply includes a voltage regulator, an inductor, an inverter for producing a high frequency square wave current of alternating polarity, an improved inverter voltage clamping circuit, a step up transformer, an output rectifier for producing a dc voltage at the output of each module, and a current sensor for sensing output current. The power supply also provides dynamic response to varying loads by controlling the voltage regulator duty cycle and circuitry is provided for sensing incipient arc currents at the output of the power supply to simultaneously decouple the power supply circuitry from the arcing load. The power supply includes a plurality of discrete switching type dc--dc converter modules. 5 figs.

Shimer, D.W.; Lange, A.C.

1996-10-15

118

Analysis of system wide distortion in an integrated power system utilizing a high voltage DC bus and silicon carbide power devices  

E-print Network

This research investigates the distortion on the electrical distribution system for a high voltage DC Integrated Power System (IPS). The analysis was concentrated on the power supplied to a propulsion motor driven by an ...

Fallier, William F. (William Frederick)

2007-01-01

119

Electric power emergency handbook  

SciTech Connect

The Emergency Electric Power Administration's Emergency Operations Handbook is designed to provide guidance to the EEPA organization. It defines responsibilities and describes actions performed by the government and electric utilities in planning for, and in operations during, national emergencies. The EEPA Handbook is reissued periodically to describe organizational changes, to assign new duties and responsibilities, and to clarify the responsibilities of the government to direct and coordinate the operations of the electric utility industry under emergencies declared by the President. This Handbook is consistent with the assumptions, policies, and procedures contained in the National Plan for Emergency Preparedness. Claimancy and restoration, communications and warning, and effects of nuclear weapons are subjects covered in the appendices.

Labadie, J.R.

1980-09-01

120

Wind power. [electricity generation  

NASA Technical Reports Server (NTRS)

A historical background on windmill use, the nature of wind, wind conversion system technology and requirements, the economics of wind power and comparisons with alternative systems, data needs, technology development needs, and an implementation plan for wind energy are presented. Considerable progress took place during the 1950's. Most of the modern windmills feature a wind turbine electricity generator located directly at the top of their rotor towers.

Savino, J. M.

1975-01-01

121

Voltage-current-power meter for photovoltaic solar arrays  

NASA Technical Reports Server (NTRS)

A meter is disclosed for measuring the voltage, current, and power (VIP) parameters of a photovoltaic solar array, or array module, under sunlight operating conditions utilizing a variable load connected across the array and controlled by a voltage regulator which responds to the difference between the output voltage of the array and a programmed test voltage from a source which generates a single ramp voltage for measuring and recording current as a function of voltage, repeated ramp voltages at a high rate for peak output measurements or a DC voltage for VIP measurements at selected points on the I-V characteristic curve of the array. The voltage signal from a current sensing element, such as a shunt resistor in series with the variable load, is compared with the output current of a reference solar cell to provide a normalizing signal to be added to the signal from the current-sensing element in order to provide a record of array current as a function of array voltage, i.e., for all load conditions from short circuit to open circuit. As the normalized current is thus measured, an analog multiplier multiplies the array voltage and normalized current to provide a measurement of power. Switches are provided to selectively connect the power, P, current, I, or voltage, V, to a meter, directly or through a peak detector. At the same time any one of the parameters V, I and P may be recorded as a function of any other parameter.

Ross, Ronald G. (Inventor)

1979-01-01

122

Copper wire theft and high voltage electrical burns  

PubMed Central

High voltage electrical burns are uncommon. However in the midst of our economic recession we are noticing an increasing number of these injuries. Copper wire is a valuable commodity with physical properties as an excellent conductor of electricity making it both ubiquitous in society and prized on the black market. We present two consecutive cases referred to the National Burns Unit who sustained life threatening injuries from the alleged theft of high voltage copper wire and its omnipresence on an international scale. PMID:25356371

Francis, Eamon C; Shelley, Odhran P

2014-01-01

123

High voltage power condition systems powered by flux compression generators  

NASA Astrophysics Data System (ADS)

Compact, high-gain magnetic flux compressors (FCGs) are convenient sources of substantial energy for plasma-physics and electron-beam-physics experiments, but the need for high-voltage, fast-rising pulses is difficult to meet directly with conventional generators. While a variety of novel concepts employing simultaneous, axially-detonated explosive systems are under development, power-conditioning systems based on fuse opening switches and high-voltage transformers constitute another approach that complements the fundamental size, weight, and configuration of the small helical flux compressor. In this paper, we consider first a basic inductive store/opening switch circuit and the implications associated with, specifically, a fuse opening switch and an FCG energy source. We develop a general solution to a transformer/opening switch circuit---which also includes (as a special case) the direct inductive store/opening switch circuit (without transformer) and we report results of one elementary experiment demonstrating the feasibility of the approach.

Reinovsky, R. E.; Lindemuth, I. R.; Vorthman, J. E.

124

Mobile electric power  

SciTech Connect

Analytic Power has proven the feasibility of a mobile electric power unit in the form of a hydride fueled ion-exchange membrane (IEM) fuel cell stack. We have over 5 years experience building and testing IEM fuel cells. The power section of a 350 watt fuel cell stack weighs 4.65 pounds based on our five cell sub-stack component weights. The composite stack structure is fabricated from two components; a unitized flow field and catalyzed membrane. The lightweight unitized flow field concept was proven in the first three months of the contract. A single unit flow field weighs 0.155 pounds and can seal to 60 psi. The single cell catalyzed Nafion membrane exceeded our performance goal of 0.6 volts at 100 ASF. Stack performance points were 0.42 volts at 113 ASF and .75 volts at 96 asf.

Bloomfield, V.J.; Bloomfield, D.P.; Johnson, B.Q.

1992-01-30

125

Milligram-scale high-voltage power electronics for piezoelectric microrobots  

Microsoft Academic Search

Piezoelectric actuators can achieve high efficiency and power density in very small geometries, which shows promise for microrobotic applications, such as flapping-wing robotic insects. From the perspective of power electronics, such actuators present two challenges: high operating voltages, ranging from tens to thousands of volts, and a low electromechanical coupling factor, which necessitates the recovery of unused electrical energy. This

Michael Karpelson; Gu-yeon Wei; Robert J. Wood

2009-01-01

126

A low-power design method using multiple supply voltages  

Microsoft Academic Search

We present a low-power design method that utilizes the multiple supply voltages. The proposed method reduces the power consumption of random logic circuits by 47% on the average, with up to 15% area overhead, by the combination of \\

Mutsunori Igarashi; Kimiyoshi Usami; Kazutaka Nogami; Fumihiro Minami; Yukio Kawasaki; Takahiro Aoki; Midori Takano; S. Sonoda; M. Ichida; N. Hatanaka

1997-01-01

127

Insulation Requirements of High-Voltage Power Systems in Future Spacecraft  

NASA Technical Reports Server (NTRS)

The scope, size, and capability of the nation's space-based activities are limited by the level of electrical power available. Long-term projections show that there will be an increasing demand for electrical power in future spacecraft programs. The level of power that can be generated, conditioned, transmitted, and used will have to be considerably increased to satisfy these needs, and increased power levels will require that transmission voltages also be increased to minimize weight and resistive losses. At these projected voltages, power systems will not operate satisfactorily without the proper electrical insulation. Open or encapsulated power supplies are currently used to keep the volume and weight of space power systems low and to protect them from natural and induced environmental hazards. Circuits with open packaging are free to attain the pressure of the outer environment, whereas encapsulated circuits are imbedded in insulating materials, which are usually solids, but could be liquids or gases. Up to now, solid insulation has usually been chosen for space power systems. If the use of solid insulation is continued, when voltages increase, the amount of insulation for encapsulation also will have to increase. This increased insulation will increase weight and reduce system reliability. Therefore, non-solid insulation media must be examined to satisfy future spacecraft power and voltage demands. In this report, we assess the suitability of liquid, space vacuum, and gas insulation for space power systems.

Qureshi, A. Haq; Dayton, James A., Jr.

1995-01-01

128

Medium power voltage multipliers with a large number of stages  

NASA Technical Reports Server (NTRS)

Voltage multiplier techniques are extended at medium power levels to larger multiplication ratios. A series of dc-dc converters were built, with from 20 to 45 stages and with power levels up to 100 watts. Maximum output voltages were about 10,000 volts.

Harrigill, W. T.; Myers, I. T.

1978-01-01

129

Medium power voltage multipliers with a large number of stages  

NASA Technical Reports Server (NTRS)

Voltage multiplier techniques were extended at medium power levels to larger multiplication ratios. A series of DC-DC converters were built, with from 20 to 45 stages and with power levels up to 100 watts. Maximum output voltages were about 10,000 volts.

Harrigill, W. T.; Myers, I. T.

1978-01-01

130

High-voltage power grid disturbances during geomagnetic storms  

Microsoft Academic Search

The very strong geomagnetic storm on 13 March 1989 caused extensive disruptions of high-voltage power circuits especially in the Province of Quebec, Canada, but also to a lesser degree in Scandinavia. Similar events have occurred earlier, among others, during the great storms of 13 - 14 July 1982 and 8 - 9 February 1986. Some of the high-voltage power grid

Peter Stauning

2002-01-01

131

Conceptual definition of a high voltage power supply test facility  

NASA Technical Reports Server (NTRS)

NASA Lewis Research Center is presently developing a 60 GHz traveling wave tube for satellite cross-link communications. The operating voltage for this new tube is - 20 kV. There is concern about the high voltage insulation system and NASA is planning a space station high voltage experiment that will demonstrate both the 60 GHz communications and high voltage electronics technology. The experiment interfaces, requirements, conceptual design, technology issues and safety issues are determined. A block diagram of the high voltage power supply test facility was generated. It includes the high voltage power supply, the 60 GHz traveling wave tube, the communications package, the antenna package, a high voltage diagnostics package and a command and data processor system. The interfaces with the space station and the attached payload accommodations equipment were determined. A brief description of the different subsystems and a discussion of the technology development needs are presented.

Biess, John J.; Chu, Teh-Ming; Stevens, N. John

1989-01-01

132

High voltage power supply with modular series resonant inverters  

DOEpatents

A relatively small and compact high voltage, high current power supply for a laser utilizes a plurality of modules containing series resonant half bridge inverters. A pair of reverse conducting thyristors are incorporated in each series resonant inverter module such that the series resonant inverter modules are sequentially activated in phases 360{degree}/n apart, where n=number of modules for n>2. Selective activation of the modules allows precise output control reducing ripple and improving efficiency. Each series resonant half bridge inverter module includes a transformer which has a cooling manifold for actively circulating a coolant such as water, to cool the transformer core as well as selected circuit elements. Conductors connecting and forming various circuit components comprise hollow, electrically conductive tubes such as copper. Coolant circulates through the tubes to remove heat. The conductive tubes act as electrically conductive lines for connecting various components of the power supply. Where it is desired to make electrical isolation breaks, tubes comprised of insulating material such as nylon are used to provide insulation and continue the fluid circuit. 11 figs.

Dreifuerst, G.R.; Merritt, B.T.

1995-07-18

133

High voltage power supply with modular series resonant inverters  

DOEpatents

A relatively small and compact high voltage, high current power supply for a laser utilizes a plurality of modules containing series resonant half bridge inverters. A pair of reverse conducting thyristors are incorporated in each series resonant inverter module such that the series resonant inverter modules are sequentially activated in phases 360.degree./n apart, where n=number of modules for n>2. Selective activation of the modules allows precise output control reducing ripple and improving efficiency. Each series resonant half bridge inverter module includes a transformer which has a cooling manifold for actively circulating a coolant such as water, to cool the transformer core as well as selected circuit elements. Conductors connecting and forming various circuit components comprise hollow, electrically conductive tubes such as copper. Coolant circulates through the tubes to remove heat. The conductive tubes act as electrically conductive lines for connecting various components of the power supply. Where it is desired to make electrical isolation breaks, tubes comprised of insulating material such as nylon are used to provide insulation and continue the fluid circuit.

Dreifuerst, Gary R. (Livermore, CA); Merritt, Bernard T. (Livermore, CA)

1995-01-01

134

Human Factors Aspects of Power System Voltage Visualizations Douglas A. Wiegmann Aaron M. Rich Thomas J. Overbye Yan Sun  

E-print Network

Human Factors Aspects of Power System Voltage Visualizations Douglas A. Wiegmann Aaron M. Rich with the human factors aspects of using color contours to visualize electric power system bus voltage magnitude utility, with restructuring they are increasingly inadequate. This paper presents results of human factors

135

High voltage electrical amplifier having a short rise time  

DOEpatents

A circuit, comprising an amplifier and a transformer is disclosed that produces a high power pulse having a fast response time, and that responds to a digital control signal applied through a digital-to-analog converter. The present invention is suitable for driving a component such as an electro-optic modulator with a voltage in the kilovolt range. The circuit is stable at high frequencies and during pulse transients, and its impedance matching circuit matches the load impedance with the output impedance. The preferred embodiment comprises an input stage compatible with high-speed semiconductor components for amplifying the voltage of the input control signal, a buffer for isolating the input stage from the output stage; and a plurality of current amplifiers connected to the buffer. Each current amplifier is connected to a field effect transistor (FET), which switches a high voltage power supply to a transformer which then provides an output terminal for driving a load. The transformer comprises a plurality of transmission lines connected to the FETs and the load. The transformer changes the impedance and voltage of the output. The preferred embodiment also comprises a low voltage power supply for biasing the FETs at or near an operational voltage.

Christie, David J. (Pleasanton, CA); Dallum, Gregory E. (Livermore, CA)

1991-01-01

136

Technical evaluation of the adequacy of station electric distribution system voltages for the San Onofre Nuclear Generating Station, Unit 1  

Microsoft Academic Search

This report documents the technical evaluation of the adequacy of the station electric distribution system voltages for the San Onofre Nuclear Generating Station, Unit. The evaluation is to determine if the onsite distribution system in conjunction with the offsite power sources has sufficient capacity to automatically start and operate all Class 1E loads within the equipment voltage ratings under certain

Selan

1982-01-01

137

Students' understanding of voltage in simple parallel electric circuits  

Microsoft Academic Search

This paper reports an investigation of the performance of school students at age 15 on written diagnostic questions involving the prediction of meter readings in simple electric circuits with parallel branches. Results show that these students tend to perceive such questions in resistance?current terms, with a primary focus on resistor addition, rather than in voltage terms, with two loads being

Robin Millar; Kian Lim Beh

1993-01-01

138

Low power, high voltage power supply with fast rise/fall time  

NASA Technical Reports Server (NTRS)

A low power, high voltage power supply system includes a high voltage power supply stage and a preregulator for programming the power supply stage so as to produce an output voltage which is a predetermined fraction of a desired voltage level. The power supply stage includes a high voltage, voltage doubler stage connected to receive the output voltage from the preregulator and for, when activated, providing amplification of the output voltage to the desired voltage level. A first feedback loop is connected between the output of the preregulator and an input of the preregulator while a second feedback loop is connected between the output of the power supply stage and the input of the preregulator.

Bearden, Douglas B. (Inventor)

2007-01-01

139

Power processing units for high power solar electric propulsion  

NASA Astrophysics Data System (ADS)

An evaluation of high-power processing units (PPUs) for multimegawatt solar electric propulsion (SEP) vehicles using advanced ion thrusters is presented. Significant savings of scale are possible for PPUs used to supply power to ion thrusters operating at 0.1 to 1.5 MWe per thruster. The PPU specific mass is found to be strongly sensitive to variations in the ion thruster's power per thruster and moderately sensitive to variations in the thruster's screen voltage due to varying the I(sp) of the thruster. Each PPU consists of a dc-to-dc converter to increase the voltage from the 500 V dc of the photovoltaic power system to the 5 to 13 kV dc required by the ion thrusters.

Frisbee, Robert H.; Das, Radhe S.; Krauthamer, Stanley

140

Optimization of power systems with voltage security constraints  

NASA Astrophysics Data System (ADS)

As open access market principles are applied to power systems, significant changes in their operation and control are occurring. In the new marketplace, power systems are operating under higher loading conditions as market influences demand greater attention to operating cost versus stability margins. Since stability continues to be a basic requirement in the operation of any power system, new tools are being considered to analyze the effect of stability on the operating cost of the system, so that system stability can be incorporated into the costs of operating the system. In this thesis, new optimal power flow (OPF) formulations are proposed based on multi-objective methodologies to optimize active and reactive power dispatch while maximizing voltage security in power systems. The effects of minimizing operating costs, minimizing reactive power generation and/or maximizing voltage stability margins are analyzed. Results obtained using the proposed Voltage Stability Constrained OPF formulations are compared and analyzed to suggest possible ways of costing voltage security in power systems. When considering voltage stability margins the importance of system modeling becomes critical, since it has been demonstrated, based on bifurcation analysis, that modeling can have a significant effect of the behavior of power systems, especially at high loading levels. Therefore, this thesis also examines the effects of detailed generator models and several exponential load models. Furthermore, because of its influence on voltage stability, a Static Var Compensator model is also incorporated into the optimization problems.

Rosehart, William Daniel

141

Robust distribution and use of electric power  

NASA Astrophysics Data System (ADS)

One of the major problems related to the simultaneous operation of electrical converters in a wide open power system is the concordance between the characteristics of the feeder itself and the load. Nowadays we usually call Electric Power Quality or Electromagnetic Compatibility to this Concordance Degree. Currently, the most important non concordance are voltage sag (voltage dip) and short time interruptions, that is: decreasings in voltage RMS value lasting from some tenths of a second to several seconds. Current analysis usually study this problem from the feeder side, by means of morphological or stadistical approaches, or from the load side in order to evaluate immunity, emission or specific solutions. This line of research, undoubtly needed provided we need to know the current state of the power system and to increase the concordance degree, is not enough because of the huge variability between power lines and from one instant to another. Moreover, the legal boundaries that can support business decisions are not developed yet. The proposed new theory is widely contrasted by field and laboratory measurement. Detailed analysis include instant voltage, instant current, power system and load effects from many places inside the power system of Spain. This theory is a novel approach to the determination of Concordance Degree (CG) of a whole system (be it a distribution line or a single machine) and to the corrective steps needed to increase it. In addition, the proposed model allow a quantitative evaluation of corrective actions like the increase of energy system storage (in a mechanical to electrical convertible form) or/and the increase of the supplied reactive power. Profitability of corrective actions is mainly a function of the number of voltage dips (sags) and short time interruptions that happen in a given period of time. To reduce this number we have studied and developed new fault characterization and location algorithms designed specifically for medium voltage networks. These algorithms, applied to the recorded faults obtained in the widespread measure campaign we have performed, have allowed the analysis of the Fault Repeatness. Last, new lines of research are suggested, mainly focused on more detailed analytical models together with laboratory and field experiences, in order to provide a solid ground for the development of a realistic standard environment able to provide the highest Concordance Degree at the lowest system-as-a-whole cost.

Catalan Izquierdo, Saturnino

2001-07-01

142

Generalized theory of electric power  

Microsoft Academic Search

Contents The paper presents the generalized theory of electric power, which makes it possible to estimate the operation of complex electric circuits. Use has been made of the correlation analysis and new definitions have been found for various kinds of power occurring in such systems. It has been shown that both the active and the reactive power depend on the

Z. Nowomiejski

1981-01-01

143

Incorporating voltage security into the planning, operation and monitoring of restructured electric energy markets  

NASA Astrophysics Data System (ADS)

As open access market principles are applied to power systems, significant changes are happening in their planning, operation and control. In the emerging marketplace, systems are operating under higher loading conditions as markets focus greater attention to operating costs than stability and security margins. Since operating stability is a basic requirement for any power system, there is need for newer tools to ensure stability and security margins being strictly enforced in the competitive marketplace. This dissertation investigates issues associated with incorporating voltage security into the unbundled operating environment of electricity markets. It includes addressing voltage security in the monitoring, operational and planning horizons of restructured power system. This dissertation presents a new decomposition procedure to estimate voltage security usage by transactions. The procedure follows physical law and uses an index that can be monitored knowing the state of the system. The expression derived is based on composite market coordination models that have both PoolCo and OpCo transactions, in a shared stressed transmission grid. Our procedure is able to equitably distinguish the impacts of individual transactions on voltage stability, at load buses, in a simple and fast manner. This dissertation formulates a new voltage stability constrained optimal power flow (VSCOPF) using a simple voltage security index. In modern planning, composite power system reliability analysis that encompasses both adequacy and security issues is being developed. We have illustrated the applicability of our VSCOPF into composite reliability analysis. This dissertation also delves into the various applications of voltage security index. Increasingly, FACT devices are being used in restructured markets to mitigate a variety of operational problems. Their control effects on voltage security would be demonstrated using our VSCOPF procedure. Further, this dissertation investigates the application of steady state voltage stability index to detect potential dynamic voltage collapse. Finally, this dissertation examines developments in representation, standardization, communication and exchange of power system data. Power system data is the key input to all analytical engines for system operation, monitoring and control. Data exchange and dissemination could impact voltage security evaluation and therefore needs to be critically examined.

Nair, Nirmal-Kumar

144

Effects of neutral point reactors and series capacitors on geomagnetically induced currents in a high-voltage electric power transmission system  

NASA Astrophysics Data System (ADS)

Geomagnetically induced currents (GIC) are DC-like currents compared to power transmission frequencies. Consequently, it may be possible to reduce the magnitudes of GIC by installing resistive components or series capacitors into a power grid. We simulate the effects of neutral point reactors and series capacitors on GIC in the Finnish 400 kV network. Reactors add an additional resistance to earthing leads of transformers, and series capacitors block the flow of GIC in transmission lines. The geoelectric field impacting the system is considered to be uniform. The use of reactors does not necessarily reduce the GIC risk. Although the installation of reactors tends to decrease GIC on the average, maximum GIC may even increase. Assuming a reactor at all stations results in a 50% reduction of the maximum GIC compared to the situation with no reactors. With up to four series capacitors, the maximum GIC is reduced by 40% when they are optimally located. However, even small changes in the topology of the grid can cause large changes in GIC. A combination of reactors and series capacitors could in principle provide a way to diminish the GIC risk. This study also emphasizes the difficulty of preventing GIC problems by these means.

ArajäRvi, Esko; Pirjola, Risto; Viljanen, Ari

2011-11-01

145

A high voltage electrical burn of lung parenchyma.  

PubMed

High voltage electrical trauma may cause severe visceral injuries. We report a case of direct electrical injury to the lung parenchyma, without evidence of any thoracic wall contact injury, in an electrician who sustained a 20 kV-electrical shock while working in a substation cubicle. The diagnosis of a true electrical burn of the left lower lobe was suggested early on by imaging and then confirmed by surgical exploration, histological findings and the significant improvement of the patient's condition following resection of the infarcted lobe. All possible causes of bronchial and pulmonary pathologies in such a context were ruled out. The fatal outcome of two previous similar cases and the generally high mortality of any electrical visceral injury support early surgical management as the only rational life-saving treatment. Current pathophysiological knowledge substantiates the theory of an isolated visceral injury located far away from the contact wounds. However, the pathogenesis of such severe injuries is not entirely understood. PMID:10925192

Masanès, M J; Gourbière, E; Prudent, J; Lioret, N; Febvre, M; Prévot, S; Lebeau, B

2000-11-01

146

VOLTAGE COLLAPSE AVOIDANCE IN POWER SYSTEMS: A RECEDING HORIZON APPROACH  

Microsoft Academic Search

In this paper, a receding horizon control approach is developed for voltage stabilization in power systems. The primary focus is on a benchmark system proposed in the context of a European project. The system is termed hybrid due to the finite set of control inputs, state automata description of the voltage primary controller and their interactions with the load nonlinear

S. A. ATTIA; M. ALAMIR; C. CANUDAS DE WIT

2006-01-01

147

Dynamic voltage scaling on a low-power microprocessor  

Microsoft Academic Search

Power consumption is the limiting factor for the functionality of future wearable devices. Since interactive applications like wireless information access generate bursts of activities, it is important to match the performance of the wearable device accordingly. This paper describes a system with a microprocessor whose speed can be varied (frequency scaling) as well as its supply voltage. Voltage scaling is

Johan A. Pouwelse; Koen Langendoen; Henk J. Sips

2001-01-01

148

High voltage power condition systems powered by flux compression generators  

SciTech Connect

Compact, high-gain magnetic flux compressors (FCGs) are convenient sources of substantial energy for plasma-physics and electron-beam-physics experiments, but the need for high-voltage, fast-rising pulses is difficult to meet directly with conventional generators. While a variety of novel concepts employing simultaneous, axially- detonated explosive systems are under development, power-conditioning systems based on fuse opening switches and high-voltage transformers constitute another approach that complements the fundamental size, weight, and configuration of the small helical flux compressor. In this paper, we consider first a basic inductive store/opening switch circuit and the implications associated with, specifically, a fuse opening switch and an FCG energy source. We develop a general solution to a transformer/opening switch circuit---which also includes (as a special case) the direct inductive store/opening switch circuit (without transformer) and we report results of one elementary experiment demonstrating the feasibility of the approach. 9 figs.

Reinovsky, R.E.; Lindemuth, I.R.; Vorthman, J.E.

1989-01-01

149

Investigation of voltages and electric fields in silicon radiation detectors using a scanning electron microscope  

NASA Astrophysics Data System (ADS)

The paper describes qualitative and quantitative methods to measure voltages and electric fields in a biased silicon p +/n -/n + radiation detector with a scanning electron microscope using voltage-contrast phenomenon. The contrast is converted to voltage mathematically using simple equations. After splitting the detector, voltages and electric fields inside the detector can be imaged and measured. The results are compared with capacitance-voltage measurements and 2D electrical simulations.

Leinonen, Kari

2005-12-01

150

Optimized deep trench isolation for high voltage smart power process  

Microsoft Academic Search

This work describes the electrical performance of high voltage deep trench isolation on SOI wafers. Several process and design related effects on the electrical isolation capability are investigated. Several process parameters during the trench process are examined with regard to isolation capability as well as defect generation. Trench edge geometry and layout have also a very strong impact on the

R. Lerner; U. Eckoldt; A. Hoelke; A. Nevin; G. Stoll

2005-01-01

151

Improving Electrical Efficiency of Edm Power Supply  

NASA Astrophysics Data System (ADS)

This paper briefly presents the principal types of Pulse Generators for Electrical Discharge Machining and ways to improve electrical efficiency. A resonant converter with series-parallel LCC circuit, for EDM applications, was analyzed by PSpice simulation. The performances of EDM Power Supply were improved by adding an energy recovering - voltage limiter circuit. The shape of current pulse was changed by adding a supplementary MOSFET Switch in parallel with the gap. Two or more converters can be parallelized, in this way output current can be changed. A bloc-schema was conceived for EDM experimental set up

Toma, Emanoil; Simion, Carmen Mihaela

2014-11-01

152

Very-high-frequency low-voltage power delivery  

E-print Network

Power conversion for the myriad low-voltage electronic circuits in use today, including portable electronic devices, digital electronics, sensors and communication circuits, is becoming increasingly challenging due to the ...

Li, Wei, Ph. D. Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science

2013-01-01

153

Power voltage current convertor using quasi complementary MOSFET current mirrors  

PubMed Central

A voltage current convertor is described having a quasi complementary class AB architecture that is particularly suited to implementation using discrete power MOSFETs. High-voltage mirror designs are presented, enabling the construction of sources with kilovolt compliance range, tens of watts of output power and greater than 100 kHz bandwidth. G? output impedance and distortion below 1% can be obtained with no trimming or transistor matching. PMID:22312182

MacLachlan, R. A.; Riviere, C. N.

2011-01-01

154

Power voltage current convertor using quasi complementary MOSFET current mirrors.  

PubMed

A voltage current convertor is described having a quasi complementary class AB architecture that is particularly suited to implementation using discrete power MOSFETs. High-voltage mirror designs are presented, enabling the construction of sources with kilovolt compliance range, tens of watts of output power and greater than 100 kHz bandwidth. G? output impedance and distortion below 1% can be obtained with no trimming or transistor matching. PMID:22312182

Maclachlan, R A; Riviere, C N

2011-10-13

155

MULTIFUNCTIONAL CAPABILITY OF A HIGH-VOLTAGE AC POWER CONDITIONER  

Microsoft Academic Search

Recent implementations of direct connected high-voltage ac power conditioners have focused on fundamental frequency power control, while other control objectives have not been exercised. This paper illustrates the multi-functional capability of a prototype high-voltage (11kV) conditioner and discusses the practicalities of building such a unit. Initial laboratory testing confirms that the unit can perform all four of the proposed functions,

Roger Brough; Shayne Crimp; Alister Gardiner

156

THREE DIMENSIONAL VISUALIZATIONS FOR POWER SYSTEM CONTINGENCY ANALYSIS VOLTAGE DATA  

E-print Network

THREE DIMENSIONAL VISUALIZATIONS FOR POWER SYSTEM CONTINGENCY ANALYSIS VOLTAGE DATA Y. Sun IEEE security assessment is critical for detecting underlying problems in a power system. More frequent CA computation is required in the deregulated power markets to monitor the state of the system under "what if

157

HERA-B ELECTRIC POWER Power Distribution  

E-print Network

Notstrom 1 x 25 16 16 Installed power (kVA) 38 x 16 row 1-4, 6 3 x 25 row 5 9 x 16 Room 100: HERAHERA-B ELECTRIC POWER Power Distribution: HV = Hauptverteilung (main distribution frame) UV alarm etc.) 400 A = 400 A * 380 V = 263 kW 1~ = 220 V; 3~ = 380 v Power cable = Emergency power cable

158

NASCAP modelling of high-voltage power system interactions with space charged-particle environments  

NASA Technical Reports Server (NTRS)

A simple space power system operating in geosynchronous orbit was analyzed. This system consisted of two solar array wings and a central body. Each solar array wing was considered to be divided into three regions operating at 2000 volts. The center body was considered to be an electrical ground with the array voltages both positive and negative relative to ground. The system was analyzed for both a normal environment and a moderate geomagnetic substorm environment. Initial results indicate a high probability of arcing at the interconnects on the negative operating voltage wing. The dielectric strength of the substrate may be exceeded giving rise to breakdown in the bulk of the material. The geomagnetic substorm did not seem to increase the electrical gradients at the interconnects on the negative operating voltage wing but did increase the gradients on the positive operating voltage wing which could result in increased coupling current losses.

Stevens, N. J.; Roche, J. C.; Mandell, M. J.

1979-01-01

159

Predictive strategy to reduce common-mode voltages on power converters  

Microsoft Academic Search

This work presents a predictive strategy that effectively mitigates common-mode voltages from power converters, that cause overvoltage stress to the winding insulation and bearings deterioration, reducing the lifetime of electric machines. The strategy must be implemented under a predictive current control method that replaces modulation stages and linear current controllers, usually employed with PWM-converters. The method was experimentally tested on

R. Vargas; U. Ammann; J. Rodriguez; J. Pontt

2008-01-01

160

30 CFR 56.12071 - Movement or operation of equipment near high-voltage power lines.  

Code of Federal Regulations, 2010 CFR

...DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity § 56.12071 Movement or operation of equipment near high-voltage power lines. When equipment must be moved or...

2010-07-01

161

30 CFR 56.12071 - Movement or operation of equipment near high-voltage power lines.  

Code of Federal Regulations, 2013 CFR

...DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity § 56.12071 Movement or operation of equipment near high-voltage power lines. When equipment must be moved or...

2013-07-01

162

30 CFR 56.12071 - Movement or operation of equipment near high-voltage power lines.  

Code of Federal Regulations, 2014 CFR

...DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity § 56.12071 Movement or operation of equipment near high-voltage power lines. When equipment must be moved or...

2014-07-01

163

E-beam high voltage switching power supply  

DOEpatents

A high power, solid state power supply is described for producing a controllable, constant high voltage output under varying and arcing loads suitable for powering an electron beam gun or other ion source. The present power supply is most useful for outputs in a range of about 100-400 kW or more. The power supply is comprised of a plurality of discrete switching type dc-dc converter modules, each comprising a voltage regulator, an inductor, an inverter for producing a high frequency square wave current of alternating polarity, an improved inverter voltage clamping circuit, a step up transformer, and an output rectifier for producing a dc voltage at the output of each module. The inputs to the converter modules are fed from a common dc rectifier/filter and are linked together in parallel through decoupling networks to suppress high frequency input interactions. The outputs of the converter modules are linked together in series and connected to the input of the transmission line to the load through a decoupling and line matching network. The dc-dc converter modules are phase activated such that for n modules, each module is activated equally 360{degree}/n out of phase with respect to a successive module. The phased activation of the converter modules, combined with the square current waveforms out of the step up transformers, allows the power supply to operate with greatly reduced output capacitance values which minimizes the stored energy available for discharge into an electron beam gun or the like during arcing. The present power supply also provides dynamic response to varying loads by controlling the voltage regulator duty cycle using simulated voltage feedback signals and voltage feedback loops. Circuitry is also provided for sensing incipient arc currents reflected at the output of the power supply and for simultaneously decoupling the power supply circuitry from the arcing load. 7 figs.

Shimer, D.W.; Lange, A.C.

1997-03-11

164

E-beam high voltage switching power supply  

DOEpatents

A high power, solid state power supply is described for producing a controllable, constant high voltage output under varying and arcing loads suitable for powering an electron beam gun or other ion source. The present power supply is most useful for outputs in a range of about 100-400 kW or more. The power supply is comprised of a plurality of discrete switching type dc-dc converter modules, each comprising a voltage regulator, an inductor, an inverter for producing a high frequency square wave current of alternating polarity, an improved inverter voltage clamping circuit, a step up transformer, and an output rectifier for producing a dc voltage at the output of each module. The inputs to the converter modules are fed from a common dc rectifier/filter and are linked together in parallel through decoupling networks to suppress high frequency input interactions. The outputs of the converter modules are linked together in series and connected to the input of the transmission line to the load through a decoupling and line matching network. The dc-dc converter modules are phase activated such that for n modules, each module is activated equally 360.degree./n out of phase with respect to a successive module. The phased activation of the converter modules, combined with the square current waveforms out of the step up transformers, allows the power supply to operate with greatly reduced output capacitance values which minimizes the stored energy available for discharge into an electron beam gun or the like during arcing. The present power supply also provides dynamic response to varying loads by controlling the voltage regulator duty cycle using simulated voltage feedback signals and voltage feedback loops. Circuitry is also provided for sensing incipient arc currents reflected at the output of the power supply and for simultaneously decoupling the power supply circuitry from the arcing load.

Shimer, Daniel W. (Danville, CA); Lange, Arnold C. (Livermore, CA)

1997-01-01

165

Electric power applications of superconductivity  

Microsoft Academic Search

The development of superconducting systems for electric power is driven by the promise of improved efficiency, smaller size, and reduced weight as compared to existing technologies and by the possibility of new applications. Superconducting power components can also contribute to improved power quality and increased system reliability. This paper addresses historical developments and technology status of four superconducting power applications:

WILLIAM V. HASSENZAHL; DREW W. HAZELTON; BRIAN K. JOHNSON; PETER KOMAREK; MATHIAS NOE; CHANDRA T. REIS

2004-01-01

166

Voltage Stability Impact of Grid-Tied Photovoltaic Systems Utilizing Dynamic Reactive Power Control  

NASA Astrophysics Data System (ADS)

Photovoltaic (PV) DGs can be optimized to provide reactive power support to the grid, although this feature is currently rarely utilized as most DG systems are designed to operate with unity power factor and supply real power only to the grid. In this work, the voltage stability of a power system embedded with PV DG is examined in the context of the high reactive power requirement after a voltage sag or fault. A real-time dynamic multi-function power controller that enables renewable source PV DGs to provide the reactive power support necessary to maintain the voltage stability of the microgrid, and consequently, the wider power system is proposed. The loadability limit necessary to maintain the voltage stability of an interconnected microgrid is determined by using bifurcation analysis to test for the singularity of the network Jacobian and load differential equations with and without the contribution of the DG. The maximum and minimum real and reactive power support permissible from the DG is obtained from the loadability limit and used as the limiting factors in controlling the real and reactive power contribution from the PV source. The designed controller regulates the voltage output based on instantaneous power theory at the point-of-common coupling (PCC) while the reactive power supply is controlled by means of the power factor and reactive current droop method. The control method is implemented in a modified IEEE 13-bus test feeder system using PSCADRTM power system analysis software and is applied to the model of a Tampa ElectricRTM PV installation at Lowry Park Zoo in Tampa, FL. This dissertation accomplishes the systematic analysis of the voltage impact of a PV DG-embedded power distribution system. The method employed in this work bases the contribution of the PV resource on the voltage stability margins of the microgrid rather than the commonly used loss-of-load probability (LOLP) and effective load-carrying capability (ELCC) measures. The results of the proposed method show good improvement in the before-, during-, and post-start voltage levels at the motor terminals. The voltage stability margin approach provides the utility a more useful measure in sizing and locating PV resources to support the overall power system stability in an emerging smart grid.

Omole, Adedamola

167

Electric vehicle DC charger integrated within a photovoltaic power system  

Microsoft Academic Search

Mitigation of the variability in output power of renewable generators such as solar photovoltaic (PV) systems is a growing concern as these generators reach higher penetrations on electric grids. This paper presents a system where a bidirectional, highly efficient, DC-DC electric vehicle (EV) charger is placed between the high-voltage DC bus of a PV system and the EV battery. In

Joshua Traube; Fenglong Lu; Dragan Maksimovic

2012-01-01

168

Aggregation of voltage and frequency dependent electrical loads  

Microsoft Academic Search

Electrical loads play a very important role in the behaviour of an electric power system. Since there is a tremendous number of different loads in the system, representing each load with its own model becomes impractical for system level studies. This thesis deals with the issue of aggregating loads to simplify system level studies. Six new and accurate aggregate static

Kwok-Wai Louie

1999-01-01

169

Performance Comparison of Voltage Stability Indices for Weak Bus Identification in Power Systems  

NASA Astrophysics Data System (ADS)

Voltage collapse event is identified as complex and localized in nature but its effect is extensive once occurred. The vital effect of voltage collapse would be the total system collapse or blackouts which would cost a large loss to utility companies. Eventually, on- line monitoring of power system stability has become an important factor for electric power utilities. The last utmost option to avert voltage collapse incident from occurring is by the implementation of under voltage load shedding scheme. The identification of location for load shedding is the main motivation of the study. The weakest bus in a power system is identified as the location for load shedding. This location is obtained using voltage stability index Ld. The performance and effectiveness of Ld index is compared with Fast Voltage Stability Index (FVSI) and Le Index. The results obtained indicate that Ld Index can be used to identify the weak bus in a power system and consequently for the placement of UVLS relays in a power system network.

Verayiah, R.; Mohamed, A.; Shareef, H.; Zainal Abidin, I. Hj

2013-06-01

170

Determination method of equivalent insulation test voltage at room temperature for high temperature superconducting power apparatus with coil structure  

Microsoft Academic Search

This paper deals with the determination method of the equivalent insulation test voltage at room temperature that secures the reliability of the cryogenic electrical insulation of the high temperature superconducting (HTS) power apparatus. The high voltage test is related to the apparatus with coil structure at the stages of its development, manufacturing and shipment. In the test method, the equivalent

M. Hara; T. Kurihara; T. Nishioka; J. Suehiro; H. Okamoto

2004-01-01

171

Review on partial discharge detection techniques related to high voltage power equipment using different sensors  

NASA Astrophysics Data System (ADS)

When operating an equipment or a power system at the high voltage, problems associated with partial discharge (PD) can be tracked down to electromagnetic emission, acoustic emission or chemical reactions such as the formation of ozone and nitrous oxide gases. The high voltage equipment and high voltage installation owners have come to terms with the need for conditions monitoring the process of PD in the equipments such as power transformers, gas insulated substations (GIS), and cable installations. This paper reviews the available PD detection methods (involving high voltage equipment) such as electrical detection, chemical detection, acoustic detection, and optical detection. Advantages and disadvantages of each method have been explored and compared. The review suggests that optical detection techniques provide many advantages in the consideration of accuracy and suitability for the applications when compared to other techniques.

Yaacob, M. M.; Alsaedi, M. A.; Rashed, J. R.; Dakhil, A. M.; Atyah, S. F.

2014-12-01

172

Review on partial discharge detection techniques related to high voltage power equipment using different sensors  

NASA Astrophysics Data System (ADS)

When operating an equipment or a power system at the high voltage, problems associated with partial discharge (PD) can be tracked down to electromagnetic emission, acoustic emission or chemical reactions such as the formation of ozone and nitrous oxide gases. The high voltage equipment and high voltage installation owners have come to terms with the need for conditions monitoring the process of PD in the equipments such as power transformers, gas insulated substations (GIS), and cable installations. This paper reviews the available PD detection methods (involving high voltage equipment) such as electrical detection, chemical detection, acoustic detection, and optical detection. Advantages and disadvantages of each method have been explored and compared. The review suggests that optical detection techniques provide many advantages in the consideration of accuracy and suitability for the applications when compared to other techniques.

Yaacob, M. M.; Alsaedi, M. A.; Rashed, J. R.; Dakhil, A. M.; Atyah, S. F.

2014-09-01

173

Transient voltage characterization for automotive 42 volt power systems  

Microsoft Academic Search

The rapid escalation of electrical content in current and future automotive applications has necessitated the need for significant increases in electrical power. To meet this demand, automotive manufacturers are developing 42 volt power distribution systems. 42 volts will better meet the power requirements of these, new features and also permit the electrification of ancillaries up to approximately 10 kW which

T. P. Diez; S. A. Alles; R. K. Frazier

2000-01-01

174

CPFLOW for Power Tracer and Voltage Monitoring  

E-print Network

(Continuation Power Flow), a comprehensive software tool for tracing power system steady-state behaviors due of control devices for steady-state security enhancements · evaluating the effects of different load models Engineering and Theory Center Ithaca, NY 14853 Phone: 607-255-5270 Fax: 607-255-9072 Email: chiang

175

Flexible IGBT modules for high voltage high power modulator applications  

Microsoft Academic Search

Summary form only given. Modern RF accelerators, plasma implanters, and certain microwave modulators require sustained high average and peak powers to drive an assortment of dynamic loads. North Star has developed a standard solid-state module using a minimum number of IGBTs and parallel pulse transformers to provide as much as 7.5 MW peak power at voltages as great as 125

R. J. Richter-Sand; R. J. Adler

2001-01-01

176

Reliability, Electric Power, and Public Versus Private Goods  

E-print Network

Reliability, Electric Power, and Public Versus Private Goods: A New Look at the Role of Markets ignored several important technological constraints and public goods that affect the way in which power is delivered. Some of these public goods include voltage, frequency, and reliability of lines. Similarly

177

Extra high voltage power transmission. (Latest citations from the NTIS bibliographic database). Published Search  

SciTech Connect

The bibliography contains citations concerning the design, construction, and use of extra high voltage power transmission lines. Both underground and overhead lines are discussed, as well as superconducting and resistive cryogenic lines. Health, safety, and psychological aspects of the electrical field, corona, ozone, and acoustic effects of these lines are discussed. New conductors, insulators, mounting, monitoring, control, and lightning protection of EHV power transmission lines are presented. (Contains a minimum of 82 citations and includes a subject term index and title list.)

Not Available

1993-08-01

178

On Power Quality of Variable-Speed Constant-Frequency Aircraft Electric Power Systems  

Microsoft Academic Search

In this paper, a comprehensive model of the variable-speed constant-frequency aircraft electric power system is developed to study the performance characteristics of the system and, in particular, the system power quality over a frequency range of operation of 400 Hz to 800 Hz. A fully controlled active power filter is designed to regulate the load terminal voltage, eliminate harmonics, correct

Ahmad Eid; Hassan El-Kishky; Mazen Abdel-Salam; Mohamed T. El-Mohandes

2010-01-01

179

Multiple high voltage output DC-to-DC power converter  

NASA Technical Reports Server (NTRS)

Disclosed is a multiple output DC-to-DC converter. The DC input power is filtered and passed through a chopper preregulator. The chopper output is then passed through a current source inverter controlled by a squarewave generator. The resultant AC is passed through the primary winding of a transformer, with high voltages induced in a plurality of secondary windings. The high voltage secondary outputs are each solid-state rectified for passage to individual output loads. Multiple feedback loops control the operation of the chopper preregulator, one being responsive to the current through the primary winding and another responsive to the DC voltage level at a selected output.

Cronin, Donald L. (Inventor); Farber, Bertrand F. (Inventor); Gehm, Hartmut K. (Inventor); Goldin, Daniel S. (Inventor)

1977-01-01

180

A programmable voltage reference optimized for power management applications  

Microsoft Academic Search

A 3-bits programmable, low drift, high PSRR and high precision voltage reference, optimized for Power Management (PM) applications,\\u000a is presented. The topology is based on a high-performance bandgap voltage reference that presents a PSRR of up to 80 dB, which\\u000a is required in PM applications, because they employ mixed-signal circuits, where high frequency switching noise is present.\\u000a The proposed approach was

Filipe Guimarães Russo Ramos; Luís Henrique Carvalho Ferreira; Tales Cleber Pimenta

2008-01-01

181

High Voltage Power Supply With High Output Current and Low Power Consumption for Photomultiplier Tubes  

Microsoft Academic Search

In some applications, photomultiplier tubes (PMTs) are powered by battery based circuits, where the available energy is severely limited. The most simple approach to design high voltage power supplies (HVPS) for PMTs has considered resistive voltage dividers in order to bias the dynodes. However, this approach usually results in high power losses and, consequently, this undermines the PMT performance. In

José Paulo V. S. Cunha; Marcia Begalli; Maria Dias Bellar

2012-01-01

182

Electric Power Monthly  

EIA Publications

Provides monthly statistics at the state, Census division, and U.S. levels for net generation, fossil fuel consumption and stocks, quantity and quality of fossil fuels, cost of fossil fuels, electricity sales, revenue, and average revenue per kilowatthour of electricity sold.

2015-01-01

183

Optimal Placement of Unified Power Flow Controllers to Improve Dynamic Voltage Stability Using Power System Variable Based Voltage Stability Indices  

PubMed Central

This study examines a new approach to selecting the locations of unified power flow controllers (UPFCs) in power system networks based on a dynamic analysis of voltage stability. Power system voltage stability indices (VSIs) including the line stability index (LQP), the voltage collapse proximity indicator (VCPI), and the line stability index (Lmn) are employed to identify the most suitable locations in the system for UPFCs. In this study, the locations of the UPFCs are identified by dynamically varying the loads across all of the load buses to represent actual power system conditions. Simulations were conducted in a power system computer-aided design (PSCAD) software using the IEEE 14-bus and 39- bus benchmark power system models. The simulation results demonstrate the effectiveness of the proposed method. When the UPFCs are placed in the locations obtained with the new approach, the voltage stability improves. A comparison of the steady-state VSIs resulting from the UPFCs placed in the locations obtained with the new approach and with particle swarm optimization (PSO) and differential evolution (DE), which are static methods, is presented. In all cases, the UPFC locations given by the proposed approach result in better voltage stability than those obtained with the other approaches. PMID:25874560

Albatsh, Fadi M.; Ahmad, Shameem; Mekhilef, Saad; Mokhlis, Hazlie; Hassan, M. A.

2015-01-01

184

Indoor ionic propulsion technology - high voltage power system design  

Microsoft Academic Search

We present in this paper a novel propulsion technology that can directly convert high voltage electrical energy to mechanical thrust without using any moving mechanical parts and thus is noiseless and vibration free. In our prior work reported in late 2007, we demonstrated several prototypes using this technology and showed that simple triangular and circular propulsive units -Ionic Flyers -

Ho Shing Poon; Mark K. K. Lam; Maxwell Chow; Wen J. Li

2009-01-01

185

Technical Development on Partial Discharge Measurement and Electrical Insulation Techniques for Low Voltage Motors Driven by Voltage Inverters  

Microsoft Academic Search

This paper reviews the up-to-date research activities on electrical insulation techniques under repetitive surge voltages with steep wavefront for low voltage inverter-fed motors. Partial discharge (PD) inception, propagation, ageing and breakdown characteristics of magnet wires, including recently developed PD-resistant wires such as nanocomposite enameled wires, are described. PD measurement techniques under the steep-front voltages and IEC activity toward their standardization

Hitoshi Okubo; Naoki Hayakawa; Gian Carlo Montanari

2007-01-01

186

Autonomously managed electrical power systems  

NASA Technical Reports Server (NTRS)

The electric power systems for future spacecraft such as the Space Station will necessarily be more sophisticated and will exhibit more nearly autonomous operation than earlier spacecraft. These new power systems will be more reliable and flexible than their predecessors offering greater utility to the users. Automation approaches implemented on various power system breadboards are investigated. These breadboards include the Hubble Space Telescope power system test bed, the Common Module Power Management and Distribution system breadboard, the Autonomusly Managed Power System (AMPS) breadboard, and the 20 kilohertz power system breadboard. Particular attention is given to the AMPS breadboard. Future plans for these breadboards including the employment of artificial intelligence techniques are addressed.

Callis, Charles P.

1986-01-01

187

Electrical power generating system  

NASA Technical Reports Server (NTRS)

A power generating system for adjusting coupling an induction motor, as a generator, to an A.C. power line wherein the motor and power line are connected through a triac is described. The triac is regulated to normally turn on at a relatively late point in each half cycle of its operation, whereby at less than operating speed, and thus when the induction motor functions as a motor rather than as a generator, power consumption from the line is substantially reduced.

Nola, F. J. (inventor)

1983-01-01

188

Electrical power systems for Mars  

NASA Technical Reports Server (NTRS)

Electrical power system options for Mars Manned Modules and Mars Surface Bases were evaluated for both near-term and advanced performance potential. The power system options investigated for the Mission Modules include photovoltaics, solar thermal, nuclear reactor, and isotope power systems. Options discussed for Mars Bases include the above options with the addition of a brief discussion of open loop energy conversion of Mars resources, including utilization of wind, subsurface thermal gradients, and super oxides. Electrical power requirements for Mission Modules were estimated for three basic approaches: as a function of crew size; as a function of electric propulsion; and as a function of transmission of power from an orbiter to the surface of Mars via laser or radio frequency. Mars Base power requirements were assumed to be determined by production facilities that make resources available for follow-on missions leading to the establishment of a permanently manned Base. Requirements include the production of buffer gas and propellant production plants.

Giudici, Robert J.

1986-01-01

189

Electrical power systems for Mars  

NASA Astrophysics Data System (ADS)

Electrical power system options for Mars Manned Modules and Mars Surface Bases were evaluated for both near-term and advanced performance potential. The power system options investigated for the Mission Modules include photovoltaics, solar thermal, nuclear reactor, and isotope power systems. Options discussed for Mars Bases include the above options with the addition of a brief discussion of open loop energy conversion of Mars resources, including utilization of wind, subsurface thermal gradients, and super oxides. Electrical power requirements for Mission Modules were estimated for three basic approaches: as a function of crew size; as a function of electric propulsion; and as a function of transmission of power from an orbiter to the surface of Mars via laser or radio frequency. Mars Base power requirements were assumed to be determined by production facilities that make resources available for follow-on missions leading to the establishment of a permanently manned Base. Requirements include the production of buffer gas and propellant production plants.

Giudici, Robert J.

1986-05-01

190

Electric power monthly, April 1993  

SciTech Connect

The Electric Power Monthly is prepared by the Survey Management Division; Office of Coal, Nuclear, Electric and Alternate Fuels, Energy Information Administration (EIA), Department of Energy. This publication provides monthly statistics at the US, Census division, and State levels for net generation, fossil fuel consumption and stocks, quantity and quality of fossil fuels, cost of fossil fuels, electricity sales, revenue, and average revenue per kilowatthour of electricity sold. Data on net generation, fuel consumption, fuel stocks, quantity and cost of fossil fuels are also displayed for the North American Electric Reliability Council (NERC) regions.

Not Available

1993-05-07

191

Electric power monthly, May 1993  

SciTech Connect

The Electric Power Monthly (EPM) is prepared by the Survey Management Division; Office of Coal, Nuclear, Electric and Alternate Fuels, Energy Information Administration (EIA), Department of Energy. This publication provides monthly statistics at the US, Census division, and State levels for net generation, fossil fuel consumption and stocks, quantity and quality of fossil fuels, cost of fossil fuels, electricity sales, revenue, and average revenue per kilowatthour of electricity sold. Data on net generation, fuel consumption, fuel stocks, quantity and cost of fossil fuels are also displayed for the North American Electric Reliability Council (NERC) regions.

Not Available

1993-05-25

192

Voltage - a Basic Term in Electricity Shortcomings of the traditional approach and new ideas for improvement  

Microsoft Academic Search

When teaching voltage the traditional approach is based on the concept of energy and lacks any inclusion of surface charges which are present when ever a voltage can be measured within an electric circuit. Shortcomings of this approach are demonstrated and ideas for improvement are discussed. The traditional approach for introducing voltage When treating the electric circuit on lower secondary

Hermann Härtel

193

Space station electrical power system  

NASA Technical Reports Server (NTRS)

The purpose of this paper is to describe the design of the Space Station Electrical Power System. This includes the Photovoltaic and Solar Dynamic Power Modules as well as the Power Management and Distribution System (PMAD). In addition, two programmatic options for developing the Electrical Power System will be presented. One approach is defined as the Enhanced Configuration and represents the results of the Phase B studies conducted by the NASA Lewis Research Center over the last two years. Another option, the Phased Program, represents a more measured approach to reaching about the same capability as the Enhanced Configuration.

Labus, Thomas L.; Cochran, Thomas H.

1987-01-01

194

Voltages induced on a power distribution line by overhead cloud lightning  

NASA Technical Reports Server (NTRS)

Voltages induced by overhead cloud lightning on a 448 m open circuited power distribution line and the corresponding north-south component of the lightning magnetic field were simultaneously measured at the NASA Kennedy Space Center during the summer of 1986. The incident electric field was calculated from the measured magnetic field. The electric field was then used as an input to the computer program, EMPLIN, that calculated the voltages at the two ends of the power line. EMPLIN models the frequency domain field/power coupling theory found, for example, in Ianoz et al. The direction of the source, which is also one of the inputs to EMPLIN, was crudely determined from a three station time delay technique. The authors found reasonably good agreement between calculated and measured waveforms.

Yacoub, Ziad; Rubinstein, Marcos; Uman, Martin A.; Thomson, Ewen M.; Medelius, Pedro J.

1991-01-01

195

Design Techniques for High Speed Low Voltage and Low Power Non-Calibrated Pipeline Analog to Digital Converters  

E-print Network

DESIGN TECHNIQUES FOR HIGH SPEED LOW VOLTAGE AND LOW POWER NON-CALIBRATED PIPELINE ANALOG TO DIGITAL CONVERTERS A Dissertation by RIDA SHAWKY ASSAAD Submitted to the Office of Graduate Studies of Texas A&M University... in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY December 2009 Major Subject: Electrical Engineering DESIGN TECHNIQUES FOR HIGH SPEED LOW VOLTAGE AND LOW POWER NON-CALIBRATED PIPELINE ANALOG TO DIGITAL...

Assaad, Rida Shawky

2011-02-22

196

Electric power monthly, August 1993  

SciTech Connect

The Electric Power Monthly (EPM) presents monthly electricity statistics. The purpose of this publication is to provide energy decisionmakers with accurate and timely information that may be used in forming various perspectives on electric issues that lie ahead. The EPM is prepared by the Survey Management Division; Office of Coal, Nuclear, Electric and Alternate Fuels, Energy Information Administration (EIA), Department of Energy. This publication provides monthly statistics at the US, Census division, and State levels for net generation, fossil fuel consumption and stocks, quantity and quality of fossil fuels, cost of fossil fuels, electricity sales, revenue, and average revenue per kilowatthour of electricity sold. Data on net generation, fuel consumption, fuel stocks, quantity and cost of fossil fuels are also displayed for the North American Electric Reliability Council (NERC) regions.

Not Available

1993-08-13

197

Electric power monthly, September 1993  

SciTech Connect

The Electric Power Monthly (EPM) presents monthly electricity statistics. The purpose of this publication is to provide energy decisionmakers with accurate and timely information that may be used in forming various perspectives on electric issues that lie ahead. The EPM is prepared by the Survey Management Division; Office of Coal, Nuclear, Electric and Alternate Fuels, Energy Information Administration (EIA), Department of Energy. This publication provides monthly statistics at the US, Census division, and State levels for net generation, fossil fuel consumption and stocks, quantity and quality of fossil fuels, cost of fossil fuels, electricity sales, revenue, and average revenue per kilowatthour of electricity sold. Data on net generation, fuel consumption, fuel stocks, quantity and cost of fossil fuels are also displayed for the North American Electric Reliability Council (NERC) regions.

Not Available

1993-09-17

198

Hybrid electric power generating system  

Microsoft Academic Search

A hybrid power system is described which consists of: (a) a first energy converter operating on a closed Rankine cycle and including a vapor generator for vaporizing an organic working fluid in response to heat furnished from a heat source associated with the vapor generator. A turbogenerator is responsive to vaporized working fluid for generating electrical power and a condenser

Bronicki

1986-01-01

199

Hybrid electric power generating system  

Microsoft Academic Search

A hybrid power system is described which comprises a pair of energy converters operating on a closed Rankine cycle, each energy converter having a vapor generator for vaporizing a high molecular weight working fluid in response to heat furnished from a burner associated with the generator, a turbo-generator responsive to vaporized working fluid for generating electrical power, a condenser responsive

Bronicki

1978-01-01

200

Electrical Analysis of Wind Power  

NSDL National Science Digital Library

For this experiment, students use a DC motor as a generator and various shaped turbine designs to test which design produces the most electrical power. Using a fan to generate the "wind", students attach different blades made of folded paper or card stock to the motor to see how much power is generated.

Lina Jiang and Philip Peterson

201

Electric power monthly, July 1993  

SciTech Connect

The Electric Power Monthly (EPM) presents monthly electricity statistics. The purpose of this publication is to provide energy decisionmakers with accurate and timely information that may be used in forming various perspectives on electric issues that lie ahead. Data in this report are presented for a wide audience including Congress, Federal and State agencies, the electric utility industry, and the general public. The EIA collected the information in this report to fulfill its data collection and dissemination responsibilities as specified in the Federal Energy Administration Act of 1974 (Public Law 93-275) as amended.

Not Available

1993-07-29

202

Electric power monthly, June 1994  

SciTech Connect

The Electric Power Monthly (EPM) presents monthly electricity statistics. The purpose of this publication is to provide energy decisionmakers with accurate and timely information that may be used in forming various perspectives on electric issues that lie ahead. Data in this report are presented for a wide audience including Congress, Federal and State agencies, the electric utility industry, and the general public. The EIA collected the information in this report to fulfill its data collection and dissemination responsibilities as specified in the Federal Energy Administration Act of 1974 (Public Law 93-275) as amended.

Not Available

1994-06-01

203

Electric power monthly, August 1994  

SciTech Connect

The Electric Power Monthly (EPM) presents monthly electricity statistics. The purpose of this publication is to provide energy decisionmakers with accurate and timely information that may be used in forming various perspectives on electric issues that lie ahead. Data in this report are presented for a wide audience including Congress, Federal and State agencies, the electric utility industry, and the general public. The EIA collected the information in this report to fulfill its data collection and dissemination responsibilities as specified in the Federal Energy Administration Act of 1974 (Public Law 93-275) as amended.

Not Available

1994-08-24

204

High-Voltage Pulsed Current Electrical Stimulation in Wound Treatment.  

PubMed

Significance: A range of studies point to the efficacy of electrical stimulation (ES) in wound treatment, but the methodology of its application has not been determined to date. This article provides a critical review of the results of clinical trials published by researchers using high-voltage pulsed current (HVPC) to treat chronic wounds. In describing the methodology of the trials, the article gives special attention to electric stimulus parameters, the frequency of procedures and total treatment duration. Recent Advances: HVPC is a monophasic pulsed electric current that consists of double-peaked impulses (5-200??s), at very high peak-current amplitude (2-2.5?A), and high voltage (up to 500?V), at a frequency of 1-125?pulses per second. HVPC can activate "skin battery" and cellular galvanotaxis, and improves blood flow and capillary density. Critical Issues: HVPC efficacy was evaluated in conservatively treated patients with diabetic foot, venous leg and pressure ulcers (PUs), and in some patients with surgically treated venous insufficiency. Future Directions: The efficacy of HVPC as one of several biophysical energies promoting venous leg ulcer (VLU) and PU healing has been confirmed. Additional studies are needed to investigate its effect on the healing of other types of soft tissue defects. Other areas that require more research include the identification of the therapeutic effect of HVPC on infected wounds, the determination of the efficacy of cathodal versus anodal stimulation, and the minimal daily/weekly duration of HVPC required to ensure optimal promotion of wound healing. PMID:24761351

Polak, Anna; Franek, Andrzej; Taradaj, Jakub

2014-02-01

205

High-Voltage Pulsed Current Electrical Stimulation in Wound Treatment  

PubMed Central

Significance: A range of studies point to the efficacy of electrical stimulation (ES) in wound treatment, but the methodology of its application has not been determined to date. This article provides a critical review of the results of clinical trials published by researchers using high-voltage pulsed current (HVPC) to treat chronic wounds. In describing the methodology of the trials, the article gives special attention to electric stimulus parameters, the frequency of procedures and total treatment duration. Recent Advances: HVPC is a monophasic pulsed electric current that consists of double-peaked impulses (5–200??s), at very high peak-current amplitude (2–2.5?A), and high voltage (up to 500?V), at a frequency of 1–125?pulses per second. HVPC can activate “skin battery” and cellular galvanotaxis, and improves blood flow and capillary density. Critical Issues: HVPC efficacy was evaluated in conservatively treated patients with diabetic foot, venous leg and pressure ulcers (PUs), and in some patients with surgically treated venous insufficiency. Future Directions: The efficacy of HVPC as one of several biophysical energies promoting venous leg ulcer (VLU) and PU healing has been confirmed. Additional studies are needed to investigate its effect on the healing of other types of soft tissue defects. Other areas that require more research include the identification of the therapeutic effect of HVPC on infected wounds, the determination of the efficacy of cathodal versus anodal stimulation, and the minimal daily/weekly duration of HVPC required to ensure optimal promotion of wound healing. PMID:24761351

Polak, Anna; Franek, Andrzej; Taradaj, Jakub

2014-01-01

206

Trading speed for low power by choice of supply and threshold voltages  

Microsoft Academic Search

The trading of speed for low power consumption in CMOS VLSI by using the supply voltage and the threshold voltage as variables was investigated. It is shown that it is desirable to minimize the supply voltage for minimizing the power consumption. The lower bound of the supply voltage and the possible decrease in power consumption without speed loss were investigated

Dake Liu; Christer Svensson

1993-01-01

207

Motor power factor controller with a reduced voltage starter  

NASA Technical Reports Server (NTRS)

A power factor type motor controller is disclosed in which the conventional power factor constant voltage command signal is replaced during a starting interval with a graduated control voltage. This continuation-impart of a pending patent application (Serial No. 199, 765: Three Phase Factor Controller) provides a means for modifying the operation of the system for a motor start-up interval of 5 to 30 second. Using a ramp generators, an initial ramp-like signal replaces a constant power factor signal supplied by a potentiometer. The ramp-like signal is applied to a 15 terminal where it is summed with an operating power factor signal from phase detectors in order to obtain a control signal for ultimately controlling SCR devices. The SCR devices are turned on at an advancing rate with time responsive to the combination signal described rather than simply a function of a ramp-like signal alone.

Nola, F. J. (inventor)

1981-01-01

208

Power optimization of variable-voltage core-based systems  

Microsoft Academic Search

The growing class of portable systems, such as personal computing and communication devices, has resulted in a new set of system design requirements, mainly characterized by dominant importance of power minimization and design reuse. The energy efficiency of systems-on-a-chip (SOC) could be much improved if one were to vary the supply voltage dynamically at run time. We develop the design

Inki Hong; Darko Kirovski; Gang Qu; Miodrag Potkonjak; Mani B. Srivastava

1999-01-01

209

Improvements on high voltage performance of power static induction transistors  

Microsoft Academic Search

A novel structure for designing and fabricating a power static induction transistor (SIT) with excellent high breakdown voltage performance is presented. The active region of the device is designed to be surrounded by a deep trench to cut off the various probable parasitical effects that may degrade the device performance, and to avoid the parallel-current effect in particular. Three ring-shape

Wang Yongshun; Li Hairong; Wang Ziting; Li Siyuan

2009-01-01

210

Lightning induced voltage on telephone cables and power systems  

Microsoft Academic Search

Several times, the lightning damaged the electronics components of a real station of communication. Consequently, this work relates to a study on the interaction of lightning with the lightning protective system, telephone cables, and power system in order to analyze lightning induced voltages. A topology of a communication station is described and the structural lightning protection, telecommunication station, earthing network,

A. S. Ahmad; T. Aka-Ngnui

211

High-Voltage Power Supply System for Laser Isotope Separation  

Microsoft Academic Search

This report presents several concepts for Laser High-Voltage Power Supply (HVPS) Systems for a Laser Isotope Separation facility. Selection of equipments and their arrangement into operational systems is based on proven designs and on application concepts now being developed. This report has identified a number of alternative system arrangements and has provided preliminary cost estimates for each. The report includes

E. C. Ketaily; R. P. Buckner; R. L. Uhrik

1979-01-01

212

Single Event Transients in Voltage Regulators for FPGA Power Supply Applications  

NASA Technical Reports Server (NTRS)

As with other bipolar analog devices, voltage regulators are known to be sensitive to single event transients (SET). In typical applications, large output capacitors are used to provide noise immunity. Therefore, since SET amplitude and duration are generally small, they are often of secondary importance due to this capacitance filtering. In low voltage applications, however, even small SET are a concern. Over-voltages may cause destructive conditions. Under-voltages may cause functional interrupts and may also trigger electrical latchup conditions. In addition, internal protection circuits which are affected by load as well as internal thermal effects can also be triggered from heavy ions, causing dropouts or shutdown ranging from milliseconds to seconds. In the case of FPGA power supplies applications, SETS are critical. For example, in the case of Actel FPGA RTAX family, core power supply voltage is 1.5V. Manufacturer specifies an absolute maximum rating of 1.6V and recommended operating conditions between 1.425V and 1.575V. Therefore, according to the manufacturer, any transient of amplitude greater than 75 mV can disrupt normal circuit functions, and overvoltages greater than 100 mV may damage the FPGA. We tested five low dropout voltage regulators for SET sensitivity under a large range of circuit application conditions.

Poivey, Christian; Sanders, Anthony; Kim, Hak; Phan, Anthony; Forney, Jim; LaBel, Kenneth A.; Karsh, Jeremy; Pursley, Scott; Kleyner, Igor; Katz, Richard

2006-01-01

213

Application of high voltage electric field (HVEF) drying technology in potato chips  

NASA Astrophysics Data System (ADS)

In order to improve the drying efficiency and qualities of vegetable by high voltage electric field (HVEF), potato chips as a representative of vegetable was dried using a high voltage electric drying systems at 20°C. The shrinkage rate, water absorption and rehydration ratio of dried potato chips were measured. The results indicated that the drying rate of potato chips was significantly improved in the high voltage electric drying systems. The shrinkage rate of potato chips dried by high voltage electric field was 1.1% lower than that by oven drying method. And the rehydration rate of high voltage electric field was 24.6% higher than that by oven drying method. High voltage electric field drying is very advantageous and can be used as a substitute for traditional drying method.

Bai, Yaxiang; Shi, Hua; Yang, Yaxin

2013-03-01

214

Power optimization of variable voltage core-based systems  

Microsoft Academic Search

The growing class of portable systems, such as personal computing and communication devices, has resulted in a new set of system design requirements, mainly characterized by dominant importance of power minimization and design reuse. We develop the design methodology for the low power core-based real-time system-on-chip based on dynamically variable voltage hardware. The key challenge is to develop effective scheduling

Inki Hong; Darko Kirovski; Gang Qu; Miodrag Potkonjak; Mani B. Srivastava

1998-01-01

215

Electrical Prototype Power Processor for the 30-cm Mercury electric propulsion engine  

NASA Technical Reports Server (NTRS)

An Electrical Prototpye Power Processor has been designed to the latest electrical and performance requirements for a flight-type 30-cm ion engine and includes all the necessary power, command, telemetry and control interfaces for a typical electric propulsion subsystem. The power processor was configured into seven separate mechanical modules that would allow subassembly fabrication, test and integration into a complete power processor unit assembly. The conceptual mechanical packaging of the electrical prototype power processor unit demonstrated the relative location of power, high voltage and control electronic components to minimize electrical interactions and to provide adequate thermal control in a vacuum environment. Thermal control was accomplished with a heat pipe simulator attached to the base of the modules.

Biess, J. J.; Frye, R. J.

1978-01-01

216

Electric power monthly, April 1994  

SciTech Connect

The Electric Power Monthly (EPM) presents monthly electricity statistics. The purpose of this publication is to provide energy decisionmakers with accurate and timely information that may be used in forming various perspectives on electric issues that lie ahead. This publication provides monthly statistics at the U.S., Census division, and State levels for net generation, fossil fuel consumption and stocks, quantity and quality of fossil fuels, cost of fossil fuels, electricity sales, revenue, and average revenue per kilowatthour of electricity sold. Data on net generation, fuel consumption, fuel stocks, quantity and cost of fossil fuels are also displayed for the North American Electric Reliability Council (NERC) regions. This April 1994 issue contains 1993 year-end data and data through January 1994.

Not Available

1994-04-01

217

Electric power monthly, May 1994  

SciTech Connect

The Electric Power Monthly (EPM) presents monthly electricity statistics. The purpose of this publication is to provide energy decisionmakers with accurate and timely information that may be used in forming various perspectives on electric issues that lie ahead. Data in this report are presented for a wide audience including Congress, Federal and State agencies, the electric utility industry, and the general public. This publication provides monthly statistics for net generation, fossil fuel consumption and stocks, quantity and quality of fossil fuels, cost of fossil fuels, electricity sales, revenue, and average revenue per kilowatthour of electricity sold. Statistics by company and plant are published on the capability of new generating units, net generation, fuel consumption, fuel stocks, quantity and quality of fuel, and cost of fossil fuels.

Not Available

1994-05-01

218

30 CFR 75.812 - Movement of high-voltage power centers and portable transformers; permit.  

Code of Federal Regulations, 2010 CFR

...high-voltage power centers and portable transformers; permit. 75.812 Section...high-voltage power centers and portable transformers; permit. [Statutory Provisions... Power centers and portable transformers shall be deenergized...

2010-07-01

219

30 CFR 75.812 - Movement of high-voltage power centers and portable transformers; permit.  

Code of Federal Regulations, 2011 CFR

...high-voltage power centers and portable transformers; permit. 75.812 Section...high-voltage power centers and portable transformers; permit. [Statutory Provisions... Power centers and portable transformers shall be deenergized...

2011-07-01

220

30 CFR 75.812 - Movement of high-voltage power centers and portable transformers; permit.  

Code of Federal Regulations, 2014 CFR

...high-voltage power centers and portable transformers; permit. 75.812 Section...high-voltage power centers and portable transformers; permit. [Statutory Provisions... Power centers and portable transformers shall be deenergized...

2014-07-01

221

30 CFR 75.812 - Movement of high-voltage power centers and portable transformers; permit.  

Code of Federal Regulations, 2012 CFR

...high-voltage power centers and portable transformers; permit. 75.812 Section...high-voltage power centers and portable transformers; permit. [Statutory Provisions... Power centers and portable transformers shall be deenergized...

2012-07-01

222

30 CFR 75.812 - Movement of high-voltage power centers and portable transformers; permit.  

Code of Federal Regulations, 2013 CFR

...high-voltage power centers and portable transformers; permit. 75.812 Section...high-voltage power centers and portable transformers; permit. [Statutory Provisions... Power centers and portable transformers shall be deenergized...

2013-07-01

223

High-Voltage, Low-Power BNC Feedthrough Terminator  

NASA Technical Reports Server (NTRS)

This innovation is a high-voltage, lowpower BNC (Bayonet Neill-Concelman) feedthrough that enables the user to terminate an instrumentation cable properly while connected to a high voltage, without the use of a voltage divider. This feedthrough is low power, which will not load the source, and will properly terminate the instrumentation cable to the instrumentation, even if the cable impedance is not constant. The Space Shuttle Program had a requirement to measure voltage transients on the orbiter bus through the Ground Lightning Measurement System (GLMS). This measurement has a bandwidth requirement of 1 MHz. The GLMS voltage measurement is connected to the orbiter through a DC panel. The DC panel is connected to the bus through a nonuniform cable that is approximately 75 ft (approximately equal to 23 m) long. A 15-ft (approximately equal to 5-m), 50-ohm triaxial cable is connected between the DC panel and the digitizer. Based on calculations and simulations, cable resonances and reflections due to mismatched impedances of the cable connecting the orbiter bus and the digitizer causes the output not to reflect accurately what is on the bus. A voltage divider at the DC panel, and terminating the 50-ohm cable properly, would eliminate this issue. Due to implementation issues, an alternative design was needed to terminate the cable properly without the use of a voltage divider. Analysis shows how the cable resonances and reflections due to the mismatched impedances of the cable connecting the orbiter bus and the digitizer causes the output not to reflect accurately what is on the bus. After simulating a dampening circuit located at the digitizer, simulations were performed to show how the cable resonances were dampened and the accuracy was improved significantly. Test cables built to verify simulations were accurate. Since the dampening circuit is low power, it can be packaged in a BNC feedthrough.

Bearden, Douglas

2012-01-01

224

Hybrid electric power generating system  

SciTech Connect

A hybrid power system is described which consists of: (a) a first energy converter operating on a closed Rankine cycle and including a vapor generator for vaporizing an organic working fluid in response to heat furnished from a heat source associated with the vapor generator. A turbogenerator is responsive to vaporized working fluid for generating electrical power and a condenser is responsive to vapor exhausted from the turbo-generator for converting such vapor to a condensed liquid. A means is included for returning the liquid to the vapor generator; (b) a second energy converter including a thermo-electric generator having a junction, a heat source for heating the junction whereby such thermo-electric generator generates electrical power; (c) a heat pipe for conveying heat from the heat source of the second converter to the vapor generator of the first converter and to the junction; and (d) means for applying the electrical power generated by the first and second converters to an electrical load.

Bronicki, L.Y.

1986-11-11

225

Electric and magnetic field measurements in a high voltage center.  

PubMed

This paper investigates the electric and magnetic fields inside a large high voltage center constituted both of 400/150 and 150/20 kV substation areas. Results of previous field measurements and calculations in substations, made by the authors of this paper or other researchers, are presented first. The basic data distinguishing the examined center from previously examined substations follow. The main results of the field measurements in the areas of the above-mentioned center are presented in relevant diagrams. General conclusions arising from the comparison of the measured field values with relevant reference levels in force for safe public and occupational exposure as well as with the results of previous research are finally given. PMID:21917821

Safigianni, Anastasia S; Spyridopoulos, Anastasios I; Kanas, Vasilis L

2012-01-01

226

Voltage Drop  

NSDL National Science Digital Library

The first site with information on voltage drop is provided by Power and System Innovations on their Frequently Asked Questions: Voltage Drop (1) page. Visitors can read what voltage drop is, what causes it, what happens as a result of it, and what the maximum recommended voltage drop is. The second site, Basics of Electricity (2), is part of General Electric's Lighting for Business Web site. Through descriptions and illustrations, the site explains what voltage drop is and gives examples of how it is calculated using Ohm's law. The next site is a lab worksheet that is part of a class from the Electrical and Computer Engineering Department of Montana State University called Voltage Drop in Cables (3). The objective of the lesson is to determine the internal resistance of an extension cord and choose the proper wire size for a particular application. Students are given an explanation of the procedure and a number of questions to answer related to the exercise. The Oregon Building Congress offers the Lesson Plans (4) Web site and the downloadable Voltage Drop educational activity. The lesson, which is suggested to be contained within a unit on formulas and solving literal equations, explores the concept of voltage drop that is encountered in basic wiring. The fifth site entitled Explanation of Voltage Drop in a Series Circuit (5) is offered by the Horizons Electronic Lesson Plan Resource. The page describes voltage drop as an electronic concept, gives a formula determining voltage drop, provides a schematic that helps illustrate the concept, and offers a quiz and answer sheet. Next, from electrician.com, is the online Voltage Drop Calculator (6). Users input the type and size of wire being used, the voltage and phase, circuit length, and amp load to calculate voltage drop and several other parameters. The seventh site, entitled The Hazards of Voltage Drop (7), is provided within the Electrical Construction Maintenance Web site. The page describes how electrical equipment can overheat or even power down if it operates below its voltage rating. It also provides a thorough explanation of how to determine the load's operating voltage. The last site, maintained by Williamson Labs (8), is a comprehensive learning site called Elementary Electricity. Visitors will find a wealth of information here, including fun descriptions, graphics, and animations on all aspects of electricity including voltage drop.

227

Multi Power Port Converter for Hybrid Electric Vehicles Using Multi Phase Bidirectional FlyBack Topology  

Microsoft Academic Search

For hybrid electric vehicles the batteries and the drive DC-link may be at different voltages. The batteries are at low voltage to obtain higher volumetric efficiencies and the DC-link is at higher voltage to have higher efficiency on the motor side. Therefore a power interface between the batteries and the drive's DC-link is essential. This power interface should handle power

T. Bhattacharya; S. Giri V; K. Mathew; L. Umanand

2006-01-01

228

High voltage characteristics of the electrodynamic tether and the generation of power and propulsion  

NASA Technical Reports Server (NTRS)

The Tethered Satellite System (TSS) will deploy and retrieve a satellite from the Space Shuttle orbiter with a tether of up to 100 km in length attached between the satellite and the orbiter. The characteristics of the TSS which are related to high voltages, electrical currents, energy storage, power, and the generation of plasma waves are described. A number of specific features of the tether system of importance in assessing the operational characteristics of the electrodynamic TSS are identified.

Williamson, P. R.

1986-01-01

229

Software control program for 25 kW breadboard testing. [spacecraft power supplies; high voltage batteries  

NASA Technical Reports Server (NTRS)

A data acquisition software program developed to operate in conjunction with the automated control system of the 25 kW PM Electric Power System Breadboard Test facility is described. The proram provides limited interactive control of the breadboard test while acquiring data and monitoring parameters, allowing unattended continuous operation. The breadboard test facility has two positions for operating separate configurations. The main variable in each test setup is the high voltage Ni-Cd battery.

Pajak, J. A.

1981-01-01

230

Oceans and electrical power  

Microsoft Academic Search

The first part of this paper focused on the potential energy that could be extracted from salinity an'd thermal differences in the oceans; possibilities of converting marine biomass into an energy source were likewise examined. Closest to implementation are apparently schemes to harness thermal differences and wave energy. Tidal power is already producing energy in France, U.S.S.R. and China. Of

Roger H. Charlier

1982-01-01

231

The New Rules for Purchasing Electric Power  

E-print Network

THE NEW RULES FOR PURCHASING ELECTRIC POWER KENNETH M. STERN CHEM SYSTEMS, INC. TARRYTOWN, NEW YORK SUMMARY The creation of new rules for purchasing electric power is largely an outgrowth of several recent developments affecting the electric...

Stern, K.

232

Electric Power annual 1996: Volume II  

SciTech Connect

This document presents a summary of electric power industry statistics. Data are included on electric utility retail sales of electricity, revenues, environmental information, power transactions, emissions, and demand-side management.

NONE

1997-12-01

233

1-V power supply high-speed digital circuit technology with multithreshold-voltage CMOS  

Microsoft Academic Search

1-V power supply high-speed low-power digital circuit technology with 0.5-?m multithreshold-voltage CMOS (MTCMOS) is proposed. This technology features both low-threshold voltage and high-threshold voltage MOSFET's in a single LSI. The low-threshold voltage MOSFET's enhance speed performance at a low supply voltage of 1 V or less, while the high-threshold voltage MOSFET's suppress the stand-by leakage current during the sleep period.

S. Mutoh; T. Douseki; Y. Matsuya; T. Aoki; S. Shigematsu; J. Yamada

1995-01-01

234

Nuclear electric power sources  

NASA Technical Reports Server (NTRS)

Measurements on radioactive commercial p-n junction silicon cells show that these units are capable of delivering several hundred microwatts per curie of Am-241 alpha source, indicating their usefulness in such electronic devices as hearing aids, heart pacemakers, electronic watches, delay timers and nuclear dosimeter chargers. It is concluded that the Am-241 sources are superior to the beta sources used previously, because of higher alpha specific ionization and simultaneous production of low energy photons which are easily converted into photoelectrons for additional power.

Singh, J. J.

1978-01-01

235

Sensorless IPMS motor drive control for electric power steering  

Microsoft Academic Search

Key requirements of electric power steering systems such as cost implementation, minimum algorithm complexity and code length, low torque fluctuation and mechanical vibrations are fully complied by the sensorless control technique proposed in this paper, based on high voltage signal injection and measurement of an additional high frequency stator current component. The proposed rotor position estimation technique is simple and

A. Consoli; G. Scarcella; G. Scelba; A. Testa; S. De Caro

2008-01-01

236

Introduction to Electric Power Systems  

NSDL National Science Digital Library

This fine course is offered as a welcome addition to MIT's OpenCourseWare initiative. The materials from this version of "Introduction to Electric Power Systems" are from the iteration taught by Professor James Kirtley in Spring 2011. On the site, visitors can look over the syllabus, the course calendar, readings, assignments, and quizzes. The topics covered here include load flow, power electric motor drives, and polyphase networks. The site also includes a number of problem sets, along with their accompanying solutions. Visitors can look over the readings and provide feedback on the course to the site administrators.

237

One-Cycle Controlled Unified Power Quality Conditioner For Load Side Voltage Sag Compensation  

Microsoft Academic Search

Voltage quality is an important factor of the power quality of distribution systems, while voltage sags\\/dips are the most common voltage quality problems. Voltage sags\\/dips may originate both from the source side and the load side. Without proper regulation, utility customers connected to the same bus could be disturbed. This paper studies the load side voltage sags caused by the

Yang Chen; Luis Felipe Sanchez; Keyue M. Smedley; Guozhu Chen

2005-01-01

238

Electric Power Monthly, July 1990  

SciTech Connect

The Electric Power Monthly (EPM) is prepared by the Electric Power Division; Office of Coal, Nuclear, Electric and Alternate Fuels, Energy Information Administration (EIA), Department of Energy. This publication provides monthly statistics at the national, Census division, and State levels for net generation, fuel consumption, fuel stocks, quantity and quality of fuel, cost of fuel, electricity sales, and average revenue per kilowatthour of electricity sold. Data on net generation are also displayed at the North American Electric Reliability Council (NERC) region level. Additionally, company and plant level information are published in the EPM on capability of new plants, net generation, fuel consumption, fuel stocks, quantity and quality of fuel, and cost in fuel. Quantity, quality, and cost of fuel data lag the net generation, fuel consumption, fuel stocks, electricity sales, and average revenue per kilowatthour data by 1 month. This difference in reporting appears in the national, Census division, and State level tables. However, at the plant level, all statistics presented are for the earlier month for the purpose of comparison. 12 refs., 4 figs., 48 tabs.

Not Available

1990-10-12

239

Neuronal coincidence detection by voltage-sensitive electrical synapses.  

PubMed

Coincidence detection is important for functions as diverse as Hebbian learning, binaural localization, and visual attention. We show here that extremely precise coincidence detection is a natural consequence of the normal function of rectifying electrical synapses. Such synapses open to bidirectional current flow when presynaptic cells depolarize relative to their postsynaptic targets and remain open until well after completion of presynaptic spikes. When multiple input neurons fire simultaneously, the synaptic currents sum effectively and produce a large excitatory postsynaptic potential. However, when some inputs are delayed relative to the rest, their contributions are reduced because the early excitatory postsynaptic potential retards the opening of additional voltage-sensitive synapses, and the late synaptic currents are shunted by already opened junctions. These mechanisms account for the ability of the lateral giant neurons of crayfish to sum synchronous inputs, but not inputs separated by only 100 microsec. This coincidence detection enables crayfish to produce reflex escape responses only to very abrupt mechanical stimuli. In light of recent evidence that electrical synapses are common in the mammalian central nervous system, the mechanisms of coincidence detection described here may be widely used in many systems. PMID:9618553

Edwards, D H; Yeh, S R; Krasne, F B

1998-06-01

240

Stability analysis of large electric power systems  

SciTech Connect

Modern electric power systems are large and complicated, and, in many regions of the world, the generation and transmission systems are operating near their limits. Ensuring the reliable operation of the power system requires engineers to study the response of the system to various disturbances. The responses to large disturbances are examined by numerically solving the nonlinear differential-algebraic equations describing the power system. The response to small disturbances is typically studied via eigenanalysis. The Electric Power Research Institute (EPRI) recently developed the Extended Transient/Mid-term Stability Program (ETMSP) to study large disturbance stability and the Small Signal Stability Program Package (SSSP) to study small signal stability. The primary objectives of the work described in this report were to (1) explore ways of speeding up ETMSP, especially on mid-term voltage stability problems, (2) explore ways of speeding up the Multi-Area Small-Signal Stability program (MASS), one of the codes in SSSP, and (3) explore ways of increasing the size of problem that can be solved by the Cray version of MASS.

Elwood, D.M.

1993-01-01

241

High Input Voltage Discharge Supply for High Power Hall Thrusters Using Silicon Carbide Devices  

NASA Technical Reports Server (NTRS)

A power processing unit for a 15 kW Hall thruster is under development at NASA Glenn Research Center. The unit produces up to 400 VDC with two parallel 7.5 kW discharge modules that operate from a 300 VDC nominal input voltage. Silicon carbide MOSFETs and diodes were used in this design because they were the best choice to handle the high voltage stress while delivering high efficiency and low specific mass. Efficiencies in excess of 97 percent were demonstrated during integration testing with the NASA-300M 20 kW Hall thruster. Electromagnet, cathode keeper, and heater supplies were also developed and will be integrated with the discharge supply into a vacuum-rated brassboard power processing unit with full flight functionality. This design could be evolved into a flight unit for future missions that requires high power electric propulsion.

Pinero, Luis R.; Scheidegger, Robert J.; Aulsio, Michael V.; Birchenough, Arthur G.

2014-01-01

242

Electric power processing, distribution and control for advanced aerospace vehicles.  

NASA Technical Reports Server (NTRS)

The results of a current study program to develop a rational basis for selection of power processing, distribution, and control configurations for future aerospace vehicles including the Space Station, Space Shuttle, and high-performance aircraft are presented. Within the constraints imposed by the characteristics of power generation subsystems and the load utilization equipment requirements, the power processing, distribution and control subsystem can be optimized by selection of the proper distribution voltage, frequency, and overload/fault protection method. It is shown that, for large space vehicles which rely on static energy conversion to provide electric power, high-voltage dc distribution (above 100 V dc) is preferable to conventional 28 V dc and 115 V ac distribution per MIL-STD-704A. High-voltage dc also has advantages over conventional constant frequency ac systems in many aircraft applications due to the elimination of speed control, wave shaping, and synchronization equipment.

Krausz, A.; Felch, J. L.

1972-01-01

243

Preparation of Power Distribution System for High Penetration of Renewable Energy Part I. Dynamic Voltage Restorer for Voltage Regulation Pat II. Distribution Circuit Modeling and Validation  

NASA Astrophysics Data System (ADS)

Part I: Dynamic Voltage Restorer In the present power grids, voltage sags are recognized as a serious threat and a frequently occurring power-quality problem and have costly consequence such as sensitive loads tripping and production loss. Consequently, the demand for high power quality and voltage stability becomes a pressing issue. Dynamic voltage restorer (DVR), as a custom power device, is more effective and direct solutions for "restoring" the quality of voltage at its load-side terminals when the quality of voltage at its source-side terminals is disturbed. In the first part of this thesis, a DVR configuration with no need of bulky dc link capacitor or energy storage is proposed. This fact causes to reduce the size of the DVR and increase the reliability of the circuit. In addition, the proposed DVR topology is based on high-frequency isolation transformer resulting in the size reduction of transformer. The proposed DVR circuit, which is suitable for both low- and medium-voltage applications, is based on dc-ac converters connected in series to split the main dc link between the inputs of dc-ac converters. This feature makes it possible to use modular dc-ac converters and utilize low-voltage components in these converters whenever it is required to use DVR in medium-voltage application. The proposed configuration is tested under different conditions of load power factor and grid voltage harmonic. It has been shown that proposed DVR can compensate the voltage sag effectively and protect the sensitive loads. Following the proposition of the DVR topology, a fundamental voltage amplitude detection method which is applicable in both single/three-phase systems for DVR applications is proposed. The advantages of proposed method include application in distorted power grid with no need of any low-pass filter, precise and reliable detection, simple computation and implementation without using a phased locked loop and lookup table. The proposed method has been verified by simulation and experimental tests under various conditions considering all possible cases such as different amounts of voltage sag depth (VSD), different amounts of point-on-wave (POW) at which voltage sag occurs, harmonic distortion, line frequency variation, and phase jump (PJ). Furthermore, the ripple amount of fundamental voltage amplitude calculated by the proposed method and its error is analyzed considering the line frequency variation together with harmonic distortion. The best and worst detection time of proposed method were measured 1ms and 8.8ms, respectively. Finally, the proposed method has been compared with other voltage sag detection methods available in literature. Part 2: Power System Modeling for Renewable Energy Integration: As power distribution systems are evolving into more complex networks, electrical engineers have to rely on software tools to perform circuit analysis. There are dozens of powerful software tools available in the market to perform the power system studies. Although their main functions are similar, there are differences in features and formatting structures to suit specific applications. This creates challenges for transferring power system circuit models data (PSCMD) between different software and rebuilding the same circuit in the second software environment. The objective of this part of thesis is to develop a Unified Platform (UP) to facilitate transferring PSCMD among different software packages and relieve the challenges of the circuit model conversion process. UP uses a commonly available spreadsheet file with a defined format, for any home software to write data to and for any destination software to read data from, via a script-based application called PSCMD transfer application. The main considerations in developing the UP are to minimize manual intervention and import a one-line diagram into the destination software or export it from the source software, with all details to allow load flow, short circuit and other analyses. In this study, ETAP, OpenDSS, and GridLab-D are considered, and PSCMD trans

Khoshkbar Sadigh, Arash

244

The relative evimunity of the skin and cardiovascular system to the direct effects of high voltage - high frequency component electrical pulses  

Microsoft Academic Search

This paper summarizes our testing to date of commercdy available battery powered hand held electric pulse generators, sometimes called TASER's, stun guns, or Less Than Lethal Weapons (LTLW). We present the generalized electronic properties of these devices along with physiologic effects on human and animal subjects. providing a differential voltage divider factor of 1ooO. Further voltage division was accomplished using

Robert A. Stratbucker; Matthew G. Marsh

1993-01-01

245

Technical-evaluation report on the adequacy of station electric-distribution-system voltages for the San Onofre Nuclear Generating Station, Unit 1. Document No. 50-206  

Microsoft Academic Search

This report documents the technical evaluation of the adequacy of the station electric distribution system voltages for the San Onofre Nuclear Generating Station, Unit 1. The evaluation is to determine if the onsite distribution system in conjunction with the offsite power sources has sufficient capacity to automatically start and operate all Class 1E loads within the equipment voltage ratings under

Selan

1982-01-01

246

Power conversion in electrical networks  

NASA Technical Reports Server (NTRS)

Aspects of dc to dc conversion were studied in terms of a class of switching voltage regulators from a stability viewpoint. Background concepts of nonlinear system theory were considered, including the problem of obtaining suitable realizations for a class of positive operators. It is shown that the state evolution equations for a power conversion network are in general of bilinear form, and that the theory of lie groups and lie algebras is useful in analyzing such systems. The feedback stabilization of a class of bilinear systems whose state space is a manifold is also discussed.

Wood, J. R.

1974-01-01

247

ELECTRICAL POWER SYSTEM DESCRIPTION DOCUMENT  

Microsoft Academic Search

The purpose of this revision of the System Description Document (SDD) is to establish requirements that drive the design of the electrical power system and their bases to allow the design effort to proceed to License Application. This SDD is a living document that will be revised at strategic points as the design matures over time. This SDD identifies the

M. Maniyar

2004-01-01

248

The control of high-speed variable-reluctance generators in electric power systems  

Microsoft Academic Search

This work studies the control of a direct-current (DC) electric power system that is sourced by a variable-reluctance generator. The power system includes the generator and its switching inverter, a filtering capacitor, a distribution network and an electrical load. The network comprises a series resistor and inductor, while the load comprises a parallel resistor, capacitor and power sink. The voltage

D. E. Cameron; J. H. Lang

1993-01-01

249

The control of high-speed variable-reluctance generators in electric power systems  

Microsoft Academic Search

The control of a direct-current electric power system that is sourced by a variable-reluctance generator (VRG) is studied. The power system includes the generator and its switching inverter, a filtering capacitor, a distribution network, and an electrical load. The network comprises a series resistor and inductor, while the load comprises a parallel resistor, capacitor, and power sink. The voltage at

D. E. Cameron; J. H. Lang

1992-01-01

250

COOLMOSTM-a new milestone in high voltage power MOS  

Microsoft Academic Search

Recently, a new technology for high voltage power MOSFETs has been introduced: the CoolMOSTM. Based on the new device concept of charge compensation, the RDS(on) area product for e.g. 600 V transistors has been reduced by a factor of 5. The devices show no bipolar current contribution like the well known tail current observed during the turn-off phase of IGBTs.

L. Lorenz; G. Deboy; A. Knapp; M. Marz

1999-01-01

251

Electric power annual 1995. Volume II  

SciTech Connect

This document summarizes pertinent statistics on various aspects of the U.S. electric power industry for the year and includes a graphic presentation. Data is included on electric utility retail sales and revenues, financial statistics, environmental statistics of electric utilities, demand-side management, electric power transactions, and non-utility power producers.

NONE

1996-12-01

252

Module Two: Voltage; Basic Electricity and Electronics Individualized Learning System.  

ERIC Educational Resources Information Center

In this module the student will study and learn what voltage is, how it is generated, what AC (alternating current) and DC (direct current) are and why both kinds are needed, and how to measure voltages. The module is divided into six lessons: EMF (electromotive force) from chemical action, magnetism, electromagnetic induction, AC voltage, the…

Bureau of Naval Personnel, Washington, DC.

253

Electric power monthly, February 1994  

SciTech Connect

The Electric Power Monthly (EMP) presents monthly electricity statistics. The purpose of this publication is to provide energy decisionmakers with accurate and timely information that may be used in forming various perspectives on electric issues that lie ahead. Data in this report are presented for a wide audience including Congress, Federal and State agencies, the electric utility industry, and the general public. The EIA collected the information in this report to fulfill its data collection and dissemination responsibilities as specified in the Federal Energy Administration Act of 1974 (Public Law 93-275) as amended. This publication provides monthly statistics at the US, Census division, and State levels for net generation, fossil fuel consumption and stocks, quantity and quality of fossil fuels, cost of electricity sales, revenue, and average revenue per kilowatthour of electricity sold. Data on net generation, fuel consumption, fuel stocks, quantity and cost of fossil fuels are also displayed for the North American Electric Reliability Council (NERC) regions. Statistics by company and plant are published in the EPM on the capability of new generating units, net generation, fuel consumption, fuel stocks, quantity and quality of fuel, and cost of fossil fuels.

Not Available

1994-02-16

254

Electric power monthly, October 1993  

SciTech Connect

The Electric Power Monthly (EPM) presents monthly electricity statistics. The purpose of this publication is to provide energy decisionmakers with accurate and timely information that may be used in forming various perspectives on electric issues that lie ahead. Data in this report are presented for a wide audience including Congress, Federal and State agencies, the electric utility industry, and the general public. The EIA collected the information in this report to fulfill its data collection and dissemination responsibilities as specified in the Federal Energy Administration Act of 1974 (Public Law 93-275) as amended. This publication provides monthly statistics at the US, Census division, and State levels for net generation, fossil fuel consumption and stocks, quantity and quality of fossil fuels, cost of fossil fuels, electricity sales, revenue, and average revenue per kilowatthour of electricity sold. Data on net generation, fuel consumption, fuel stocks, quantity and cost of fossil fuels are also displayed for the North American Electric Reliability Council (NERC) regions. Statistics by company and plant are published in the EPM on the capability of new generating units, net generation, fuel consumption, fuel stocks, quantity and quality of fuel, and cost of fossil fuels.

Not Available

1993-10-20

255

Electric power monthly, January 1994  

SciTech Connect

The Electric Power Monthly (EPM) presents monthly electricity statistics. The purpose of this publication is to provide energy decisionmakers with accurate and timely information that may be used in forming various perspectives on electric issues that lie ahead. Data in this report are presented for a wide audience including Congress, Federal and State agencies, the electric utility industry, and the general public. The EIA collected the information in this report to fulfill its data collection and dissemination responsibilities as specified in the Federal Energy Administration Act of 1974 (Public Law 93-275) as amended. This publication provides monthly statistics at the US Census division, and State levels for net generation, fossil fuel consumption and stocks, quantity and quality of fossil fuels, cost of fossil fuels, electricity sales, revenue, and average revenue per kilowatthour of electricity sold. Data on net generation, fuel consumption, fuel stocks, quantity and cost of fossil fuels are also displayed for the North American Electric Reliability Council (NERC) regions. Statistics by company and plant are published in the EPM on the capability of new generating units, net generation, fuel consumption, fuel stocks, quantity and quality of fuel, and cost of fossil fuels.

Not Available

1994-01-26

256

Power storage system for electric railway  

SciTech Connect

This invention relates to a power storage system for electric railway which comprises a motor-generator connected to a power system for feeding an electric vehicle with electric power, and a flywheel coupled to the motor-generator, and in which the motor-generator is allowed to store the electric power and thereafter discharge it in correspondence with approach of the electric vehicle to a predetermined running section and running thereof in the section.

Kawamura, T.

1985-06-11

257

Voltage and Reactive Power Control Taking into Account of Economy and Security by using Tabu Search  

NASA Astrophysics Data System (ADS)

Due to deregulation of electric power market, the several power transactions and the distributed generators will increase year by year. The power flow in power system will vary increasingly more complex and more uncertain by them. So it is difficult for Voltage and reactive power(Q) Control (VQC) to sustain the adequate voltages in the power system. On the other hand, the economy and security are requested for power system operation and control under the competitive environment. The optimization algorithm is effective to satisfy these trade-off problem. The optimization of VQC traces the combinational optimization problem with shunt devices, transformer tap and generator terminal voltage. Tabu Search (TS), which is one of meta-heuristic approaches, is suitable for the optimization problem of VQC. Because it is able to deal with the discrete variables such as shunt devices easily and it needs few tuning parameters. In this paper, in order to realize flexible VQC which responds to the uncertain power flow with competitive environment, we propose the optimization of VQC with TS algorithm taking into account of both economy and security. The security is considered as the minimization of generator reactive outputs and transformer tap positions difference from the neutral. Moreover, the novel neighborhood condition setting focused on the control interference between voltage control equipments is applied to minimizing the objective function. It is confirmed by several numerical simulations using IEEE 14 and 57 bus system that the proposed scheme is able to ensure the security and to find the useful optimal solution efficiently.

Nakachi, Yoshiki; Kato, Atsushi; Ukai, Hiroyuki

258

Motor power factor controller with a reduced voltage starter  

NASA Technical Reports Server (NTRS)

A power factor type motor controller in which the conventional power factor constant voltage command signal is replaced during a starting interval with a graduated control voltage. The present invention adds to the three-phase system of pending application Ser. No. 199,765, filed Oct. 23, 1980, means for modifying the operation of the system for a motor start-up interval of 5 to 30 seconds. The modification is that of providing via ramp generator 174 an initial ramp-like signal which replaces a constant power factor signal supplied by potentiometer 70. The ramp-like signal is applied to terminal 40 where it is summed with an operating power factor signal from phase detectors 32, 34, and 36 to thereby obtain a control signal for ultimately controlling SCR devices 12, 14, and 16 to effect a gradual turn-on of motor 10. The significant difference of the present invention over prior art is that the SCR devices are turned on at an advancing rate with time responsive to the combination signal described rather than simply a function of a ramp-like signal alone. The added signal, the operating power factor signal, enables the production of a control signal which effectively eliminates a prior problem with many motor starting circuits, which is that of accompanying motor instabilities.

Nola, Frank J. (Inventor)

1983-01-01

259

Contribution History of Research Institutes to Electric Power Industry in Japan  

NASA Astrophysics Data System (ADS)

After reorganization of power industry in 1951, power system of Japan was remarkably expanded. To cope with this, R&D in vast area was conducted in the academy, MITI, electric power companies, manufactures, and research institutes. This paper generally describes the technical contents that the three research institutes, namely Electrotechnical Laboratory (ETL), High Voltage Power Laboratory (HVPL), and Central Research Institute of Electric Power Industry (CRIEPI), have contributed to the development of power transmission technology after the war.

Taniguchi, Haruhito; Shindo, Takatoshi

260

Decoupled power exchange model of UPFC to enhance voltage stability margin of power systems  

Microsoft Academic Search

This paper proposes a novel model of unified power flow controller (UPFC) for enhancing voltage stability margin of the power systems. This model is based upon an innovative approach where, real power exchange of series and shunt elements of UPFC are decoupled with each other. The UPFC model is incorporated into an existing Newton-Raphson load flow algorithm and Jacobian matrix

Rajive Tiwari; K. R. Niazi; Vikas Gupta

2011-01-01

261

Electric power monthly, July 1994  

SciTech Connect

The Electric Power Monthly (EPM) presents monthly electricity statistics. The purpose of this publication is to provide energy decisionmakers with accurate and timely information that may be used in forming various perspectives on electric issues that lie ahead. Data in this report are presented for a wide audience including Congress, Federal and State agencies, the electric utility industry, and the general public. The EIA collected the information in this report to fulfill its data collection and dissemination responsibilities as specified in the Federal Energy Administration Act of 1974 (Public Law 93-275) as amended. The EPM is prepared by the Survey Management Division; Office of Coal, Nuclear, Electric and Alternate Fuels, Energy Information Administration (EIA), Department of Energy. This publication provides monthly statistics at the US, Census division, and State levels for net generation, fossil fuel consumption and stocks, quantity and quality of fossil fuels, cost of fossil fuels, electricity sales, revenue, and average revenue per kilowatthour of electricity sold. Data on net generation, fuel consumption, fuel stocks, quantity and cost of fossil fuels are also displayed for the North American Electric Reliability Council (NERC) regions. Statistics by company and plant are published in the EPM on the capability of new generating units, net generation, fuel consumption, fuel stocks, quantity and quality of fuel, and cost of fossil fuels. Data on quantity, quality, and cost of fossil fuels lag data on net generation, fuel consumption, fuel stocks, electricity sales, and average revenue per kilowatthour by 1 month. This difference in reporting appears in the US, Census division, and State level tables. However, for purposes of comparison, plant-level data are presented for the earlier month.

Not Available

1994-07-01

262

Design of a high voltage input - output ratio dc-dc converter dedicated to small power fuel cell systems  

NASA Astrophysics Data System (ADS)

Consuming chemical energy, fuel cells produce simultaneously heat, water and useful electrical power [J.M. Andújar, F. Segura, Renew. Sust. Energy Rev. 13, 2309 (2009)], [J. Larminie, A. Dicks, Fuel Cell Systems Explained, 2nd edn. (John Wiley & Sons, 2003)]. As a matter of fact, the voltage generated by a fuel cell strongly depends on both the load power demand and the operating conditions. Besides, as a result of many design aspects, fuel cells are low voltage and high current electric generators. On the contrary, electric loads are commonly designed for small voltage swing and a high V/I ratio in order to minimize Joule losses. Therefore, electric loads supplied by fuel cells are typically fed by means of an intermediate power voltage regulator. The specifications of such a power converter are to be able to step up the input voltage with a high ratio (a ratio of 10 is a classic situation) and also to work with an excellent efficiency (in order to minimize its size, its weight and its losses) [A. Shahin, B. Huang, J.P. Martin, S. Pierfederici, B. Davat, Energy Conv. Manag. 51, 56 (2010)]. This paper deals with the design of this essential ancillary device. It intends to bring out the best structure for fulfilling this function. Several dc-dc converters with large voltage step-up ratios are introduced. A topology based on a coupled inductor or tapped inductor is closely studied. A detailed modelling is performed with the purpose of providing designing rules. This model is validated with both simulation and implementation. The experimental prototype is based on the following specifications: the fuel cell output voltage ranges from a 50 V open-voltage to a 25 V rated voltage while the load requires a constant 250 V voltage. The studied coupled inductor converter is compared with a classic boost converter commonly used in this voltage elevating application. Even though the voltage regulator faces severe FC specifications, the measured efficiency reaches 96% at the rated power whereas conventional boost efficiency barely achieves 91.5% in the same operating conditions.

Béthoux, O.; Cathelin, J.

2010-12-01

263

Manned spacecraft electrical power systems  

NASA Technical Reports Server (NTRS)

A brief history of the development of electrical power systems from the earliest manned space flights illustrates a natural trend toward a growth of electrical power requirements and operational lifetimes with each succeeding space program. A review of the design philosophy and development experience associated with the Space Shuttle Orbiter electrical power system is presented, beginning with the state of technology at the conclusion of the Apollo Program. A discussion of prototype, verification, and qualification hardware is included, and several design improvements following the first Orbiter flight are described. The problems encountered, the scientific and engineering approaches used to meet the technological challenges, and the results obtained are stressed. Major technology barriers and their solutions are discussed, and a brief Orbiter flight experience summary of early Space Shuttle missions is included. A description of projected Space Station power requirements and candidate system concepts which could satisfy these anticipated needs is presented. Significant challenges different from Space Shuttle, innovative concepts and ideas, and station growth considerations are discussed. The Phase B Advanced Development hardware program is summarized and a status of Phase B preliminary tradeoff studies is presented.

Simon, William E.; Nored, Donald L.

1987-01-01

264

Utility-Scale Solar Power Converter: Agile Direct Grid Connect Medium Voltage 4.7-13.8 kV Power Converter for PV Applications Utilizing Wide Band Gap Devices  

SciTech Connect

Solar ADEPT Project: Satcon is developing a compact, lightweight power conversion device that is capable of taking utility-scale solar power and outputting it directly into the electric utility grid at distribution voltage levels—eliminating the need for large transformers. Transformers “step up” the voltage of the power that is generated by a solar power system so it can be efficiently transported through transmission lines and eventually “stepped down” to usable voltages before it enters homes and businesses. Power companies step up the voltage because less electricity is lost along transmission lines when the voltage is high and current is low. Satcon’s new power conversion devices will eliminate these heavy transformers and connect a utility-scale solar power system directly to the grid. Satcon’s modular devices are designed to ensure reliability—if one device fails it can be bypassed and the system can continue to run.

None

2012-01-25

265

A top-down low power design technique using clustered voltage scaling with variable supply-voltage scheme  

Microsoft Academic Search

A novel design technique which combines a variable supply-voltage scheme and a clustered voltage scaling is presented (VS-CVS scheme). A theory to choose the optimum supply voltages in the VS-CVS scheme is discussed which enables us to perform chip design in a top-down fashion. Level-shifting flip-flops are developed which reduce power, delay and area penalties significantly. Application of this technique

Mototsugu Hamada; Masafumi Takahashi; Hideho Arakida; Akihiko Chiba; Toshihiro Terazawa; Takashi Ishikawa; Masahiro Kanazawa; Mutsunori Igarashi; Kimiyoshi Usami; Tadahiro Kuroda

1998-01-01

266

Electric Power Monthly, June 1990  

SciTech Connect

The EPM is prepared by the Electric Power Division; Office of Coal, Nuclear, Electric and Alternate Fuels, Energy Information Administration (EIA), Department of Energy. This publication provides monthly statistics at the national, Census division, and State levels for net generation, fuel consumption, fuel stocks, quantity and quality of fuel, electricity sales, and average revenue per kilowatthour of electricity sold. Data on net generation are also displayed at the North American Electric Reliability Council (NERC) region level. Additionally, company and plant level information are published in the EPM on capability of new plants, net generation, fuel consumption, fuel stocks, quantity and quality of fuel, and cost of fuel. Quantity, quality, and cost of fuel data lag the net generation, fuel consumption, fuel stocks, electricity sales, and average revenue per kilowatthour data by 1 month. This difference in reporting appears in the national, Census division, and State level tables. However, at the plant level, all statistics presented are for the earlier month for the purpose of comparison. 40 tabs.

Not Available

1990-09-13

267

Buried Oxide Densification for Low Power, Low Voltage CMOS Applications  

NASA Technical Reports Server (NTRS)

Special technology and circuit architecture are of growing interest for implementation of circuits which operate at low supply voltages and consume low power levels without sacrificing performance[1]. Use of thin buried oxide SOI substrates is a primary approach to simultaneously achieve these goals. A significant aspect regarding SIMOX SOI for low voltage, low power applications is the reliability and performance of the thin buried oxide. In addition, when subjected to high total dose irradiation, the silicon islands within the BOX layer of SIMOX can store charges and significantly effect the back channel threshold voltages of devices. Thus, elimination of the islands within the buried oxide (BOX) layer is preferred in order to prevent leakage through these conductive islands and charge build-up within the buried oxide layer. A differential (2-step) ramp rate as applied to full and 100 nm BOX SIMOX was previously reported to play a significant role in the stoichiometry and island formation within the buried layer[2]. This paper focus is on the properties of a thin (120nm) buried oxide as a function of the anneal ramp rate and the temperature of anneal. In this research, we have found an improvement in the buried oxide stoichiometry with the use of a slower, singular ramp rate for specified thin buried oxides, with slower ramp rates and higher temperatures of anneal suggested for reducing the presence of Si islands within the BOX layer.

Allen, L. P.; Anc, M. J.; Dolan, B.; Jiao, J.; Guss, B.; Seraphin, S.; Liu, S. T.; Jenkins, W.

1998-01-01

268

Coordination between the reactive power scheduling function and the hierarchical voltage control of the EHV ENEL system  

SciTech Connect

The paper presents the control strategies adopted at ENEL (the Italian Electric Power Company) for the automatic voltage regulation and for the short and very short term reactive power scheduling. The advanced project is based upon a three level hierarchical control of voltage and reactive power (primary, secondary and tertiary regulation) and a reactive power dispatch procedure. The three levels are characterized by specific control actions which affect systems of different size and complexity, operating in three steps. In particular, the slowest third level executes the optimal voltage profile defined by the short or very short term reactive power scheduling. The need of an effective co-ordination between the off-line reactive scheduling procedures and the on-line voltage control is pointed out in the work. Besides, the paper presents a computation procedure realized in order to simulate the steady state behavior of the electric power system submitted to the hierarchical voltage control system and its interaction with the VAR optimization program.

Corsi, S.; Marannino, P. [ENEL s.p.a., Cologno Monzese (Italy). Centro Ricerca di Automatica] [ENEL s.p.a., Cologno Monzese (Italy). Centro Ricerca di Automatica; Losignore, N. [ENEL s.p.a., Potenza (Italy). Distretto Basilicata] [ENEL s.p.a., Potenza (Italy). Distretto Basilicata; Moreschini, G.; Piccini, G. [ENEL s.p.a., Roma (Italy). Vice Direzione Movimento Energia] [ENEL s.p.a., Roma (Italy). Vice Direzione Movimento Energia

1995-05-01

269

Power processing for electric propulsion  

NASA Technical Reports Server (NTRS)

The inclusion of electric thruster systems in spacecraft design is considered. The propulsion requirements of such spacecraft dictate a wide range of thruster power levels and operational lifetimes, which must be matched by lightweight, efficient, and reliable thruster power processing systems. Electron bombardment ion thruster requirements are presented, and the performance characteristics of present power processing systems are reviewed. Design philosophies and alternatives in areas such as inverter type, arc protection, and control methods are discussed along with future performance potentials for meeting goals in the areas of power process or weight (10 kg/kW), efficiency (approaching 92 percent), reliability (0.96 for 15,000 hr), and thermal control capability (0.3 to 5 AU).

Finke, R. C.; Herron, B. G.; Gant, G. D.

1975-01-01

270

Satellite control of electric power distribution  

NASA Technical Reports Server (NTRS)

An L-band frequencies satellite link providing the medium for direct control of electrical loads at individual customer sites from remote central locations is described. All loads supplied under interruptible-service contracts are likely condidates for such control, and they can be cycled or switched off to reduce system loads. For every kW of load eliminated or deferred to off-peak hours, the power company reduces its need for additional generating capacity. In addition, the satellite could switch meter registers so that their readings automatically reflected the time of consumption. The system would perform load-shedding operations during emergencies, disconnecting large blocks of load according to predetermined priorities. Among the distribution operations conducted by the satellite in real time would be: load reconfiguration, voltage regulation, fault isolation, and capacitor and feeder load control.

Bergen, L.

1981-01-01

271

High voltage electrical burn injuries in teenage children: case studies with similarities (an indian perspective)  

PubMed Central

Summary From 1992 to 2012, a total of 911 paediatric burns were admitted and treated at Kanchi Kamakoti Childs Trust Hospital Intensive Burn Care Unit, of these 28 children had suffered electrical injuries and burns. 7 teenagers suffered high voltage electrical burn injuries: 2 were involved in train accidents which caused fatal electrical injuries, and 5 had electrical burn injuries caused by similar types of accidents, requiring Paediatric Intensive Care Unit (PICU) care, repeated surgeries and extensive rehabilitation. A common factor among these latter 5 patients was that they were injured by overhead high electrical voltage cables. Their management was labour intensive and highly costly. In this report, the type of accident, the electrical voltage that produced burns and the treatment details are elaborated. Findings included similarities in age and type of accident, and failure to implement safety procedures and apply standard norms of high voltage transmission feeder lines. PMID:24563637

Mathangi Ramakrishnan, K.; Babu, M.; Mathivanan; Ramachandran, B.; Balasubramanian, S.; Raghuram, K.

2013-01-01

272

High voltage insulation of bushing for HTS power equipment  

NASA Astrophysics Data System (ADS)

For the operation of high temperature superconducting (HTS) power equipments, it is necessary to develop insulating materials and high voltage (HV) insulation technology at cryogenic temperature of bushing. Liquid nitrogen (LN2) is an attractive dielectric liquid. Also, the polymer insulating materials are expected to be used as solid materials such as glass fiber reinforced plastic (GFRP), polytetra-fluoroethylene (PTFE, Teflon), Silicon (Si) rubber, aromatic polyamide (Nomex), EPDM/Silicon alloy compound (EPDM/Si). In this paper, the surface flashover characteristics of various insulating materials in LN2 are studied. These results are studied at both AC and impulse voltage under a non-uniform field. The use of GFRP and Teflon as insulation body for HTS bushing should be much desirable. Especially, GFRP is excellent material not only surface flashover characteristics but also mechanical characteristics at cryogenic temperature. The surface flashover is most serious problem for the shed design in LN2 and operation of superconducting equipments.

Kim, Woo-Jin; Choi, Jae-Hyeong; Kim, Sang-Hyun

2012-12-01

273

Application of Superconducting Power Cables to DC Electric Railway Systems  

NASA Astrophysics Data System (ADS)

For novel design and efficient operation of next-generation DC electric railway systems, especially for their substantial energy saving, we have studied the feasibility of applying superconducting power cables to them. In this paper it is assumed that a superconducting power cable is applied to connect substations supplying electric power to trains. An analysis model line was described by an electric circuit, which was analyzed with MATLAB-Simulink. From the calculated voltages and currents of the circuit, the regenerative brake and the energy losses were estimated. In addition, assuming the heat loads of superconducting power cables and the cryogenic efficiency, the energy saving of the total system was evaluated. The results show that the introduction of superconducting power cables could achieve the improved use of regenerative brake, the loss reduction, the decreased number of substations, the reduced maintenance, etc.

Ohsaki, Hiroyuki; Lv, Zhen; Sekino, Masaki; Tomita, Masaru

274

Power Sales to Electric Utilities  

SciTech Connect

The Public Utilities Regulatory Policies Act (PURPA) of 1979 requires that electrical utilities interconnect with qualifying facilities and purchase electricity at a rate based upon their full avoided costs (i.e., costs of providing both capacity and energy). Qualifying facilities (QF) include solar or geothermal electric units, hydropower, municipal solid waste or biomass-fired power plants, and cogeneration projects that satisfy maximum size, fuel use, ownership, location, and/or efficiency criteria. In Washington State, neither standard power purchase prices based upon a proxy ''avoided plant'', standard contracts, or a standard offer process have been used. Instead, a variety of power purchase contracts have been negotiated by developers of qualifying facilities with investor-owned utilities, public utility districts, and municipally-owned and operated utilities. With a hydro-based system, benefits associated with resource acquisition are determined in large part by how compatible the resource is with a utility's existing generation mix. Power purchase rates are negotiated and vary according to firm energy production, guarantees, ability to schedule maintenance or downtime, rights of refusal, power plant purchase options, project start date and length of contract; front-loading or levelization provisions; and the ability of the project to provide ''demonstrated'' capacity. Legislation was also enacted which allows PURPA to work effectively. Initial laws established ownership rights and provided irrigation districts, PUDs, and municipalities with expanded enabling powers. Financial processes were streamlined and, in some cases, simplified. Finally, laws were passed which are designed to ensure that development proceeds in an environmentally acceptable manner. In retrospect, PURPA has worked well within Washington. In the state of Washington, 20 small-scale hydroelectric projects with a combined generating capacity of 77 MW, 3 solid waste-to-energy facilities with 55 MW of electrical output, 4 cogeneration projects with 34.5 MW of generating capability, and 4 wastewater treatment facility digester gas-to-energy projects with 5 MW of electrical production have come on-line (or are in the final stages of construction) since the passage of PURPA. These numbers represent only a small portion of Washington's untapped and underutilized cogeneration and renewable resource generating potentials. [DJE-2005

None

1989-02-01

275

A new high-voltage electric field instrument for studying sprites  

Microsoft Academic Search

The high-voltage (HV) electric field detector is a new high-voltage, high-impedance, double Langmuir probe instrument designed for stratospheric electric field measurements. In the Sprite Balloon Campaign 2002-2003, this HV instrument was used to measure electric fields between 100 and 200 V\\/m associated with lightning discharges, which is nearly an order of magnitude higher than previously reported above 30 km in

Jeremy N. Thomas; Robert H. Holzworth; John Chin

2004-01-01

276

Electric Power Reliability in Chemical Plants  

E-print Network

The quality and reliability of utility-generated electric power is presently receiving a great deal of attention from the chemical and refining industry. What changes have taken place to make electric power reliability a major topic of discussion...

Cross, M. B.

277

TEP Power Partners Project [Tucson Electric Power  

SciTech Connect

The Arizona Governor’s Office of Energy Policy, in partnership with Tucson Electric Power (TEP), Tendril, and Next Phase Energy (NPE), formed the TEP Power Partners pilot project to demonstrate how residential customers could access their energy usage data and third party applications using data obtained from an Automatic Meter Reading (AMR) network. The project applied for and was awarded a Smart Grid Data Access grant through the U.S. Department of Energy. The project participants’ goal for Phase I is to actively engage 1,700 residential customers to demonstrate sustained participation, reduction in energy usage (kWh) and cost ($), and measure related aspects of customer satisfaction. This Demonstration report presents a summary of the findings, effectiveness, and customer satisfaction with the 15-month TEP Power Partners pilot project. The objective of the program is to provide residential customers with energy consumption data from AMR metering and empower these participants to better manage their electricity use. The pilot recruitment goals included migrating 700 existing customers from the completed Power Partners Demand Response Load Control Project (DRLC), and enrolling 1,000 new participants. Upon conclusion of the project on November 19, 2013: ? 1,390 Home Area Networks (HANs) were registered. ? 797 new participants installed a HAN. ? Survey respondents’ are satisfied with the program and found value with a variety of specific program components. ? Survey respondents report feeling greater control over their energy usage and report taking energy savings actions in their homes after participating in the program. ? On average, 43 % of the participants returned to the web portal monthly and 15% returned weekly. ? An impact evaluation was completed by Opinion Dynamics and found average participant savings for the treatment period1 to be 2.3% of their household use during this period.2 In total, the program saved 163 MWh in the treatment period of 2013.

None

2013-11-19

278

Electrical power distribution control methods, electrical energy demand monitoring methods, and power management devices  

DOEpatents

Electrical power distribution control methods, electrical energy demand monitoring methods, and power management devices are described. In one aspect, an electrical power distribution control method includes providing electrical energy from an electrical power distribution system, applying the electrical energy to a load, providing a plurality of different values for a threshold at a plurality of moments in time and corresponding to an electrical characteristic of the electrical energy, and adjusting an amount of the electrical energy applied to the load responsive to an electrical characteristic of the electrical energy triggering one of the values of the threshold at the respective moment in time.

Chassin, David P. (Pasco, WA); Donnelly, Matthew K. (Kennewick, WA); Dagle, Jeffery E. (Richland, WA)

2006-12-12

279

Electrical power distribution control methods, electrical energy demand monitoring methods, and power management devices  

DOEpatents

Electrical power distribution control methods, electrical energy demand monitoring methods, and power management devices are described. In one aspect, an electrical power distribution control method includes providing electrical energy from an electrical power distribution system, applying the electrical energy to a load, providing a plurality of different values for a threshold at a plurality of moments in time and corresponding to an electrical characteristic of the electrical energy, and adjusting an amount of the electrical energy applied to the load responsive to an electrical characteristic of the electrical energy triggering one of the values of the threshold at the respective moment in time.

Chassin, David P. (Pasco, WA); Donnelly, Matthew K. (Kennewick, WA); Dagle, Jeffery E. (Richland, WA)

2011-12-06

280

Large-scale wind power integration and voltage stability limits in regional networks  

Microsoft Academic Search

When planning and developing large-scale wind power plants in areas distant from the main power transmission system, voltage control assessments and reactive power compensation are increasingly important. Voltage stability of the regional network may be a main limitation with respect to maximum rating and operation of the wind power plant Technical constraints in relation to wind power integration in weak

M. P. Palsson; T. Toftevaag; K. Uhlen; J. O. G. Tande

2002-01-01

281

Generalized Test Bed for High-Voltage, High-Power SiC Device Characterization  

Microsoft Academic Search

A generalized 25 kV test bed developed to characterize high-voltage, high-power SiC devices is described. The test bed provides a high-speed (30 mus), high-voltage linear amplifier that is used as the pulsed power supply for parametric static measurements (curve tracer) and as the continuous high voltage power supply for inductive\\/resistive switching measurements. The test bed includes high-voltage inductors, clamping capacitors,

David Berning; Allen Hefner; Jose M. Ortiz-Rodriguez; Colleen Hood; Angel Rivera

2006-01-01

282

DC/DC Power Converter for Super-Capacitor Supplied by Electric Power Splitter  

NASA Astrophysics Data System (ADS)

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.

Haubert, T.; Mindl, P.

283

Application of Newton's optimal power flow in voltage/reactive power control  

SciTech Connect

This paper considers an application of Newton's optimal power flow to the solution of the secondary voltage/reactive power control in transmission networks. An efficient computer program based on the latest achievements in the sparse matrix/vector techniques has been developed for this purpose. It is characterized by good robustness, accuracy and speed. A combined objective function appropriate for various system load levels with suitable constraints, for treatment of the power system security and economy is also proposed. For the real-time voltage/reactive power control, a suboptimal power flow procedure has been derived by using the reduced set of control variables. This procedure is based on the sensitivity theory applied to the determination of zones for the secondary voltage/reactive power control and corresponding reduced set of regulating sources, whose reactive outputs represent control variables in the optimal power flow program. As a result, the optimal power flow program output becomes a schedule to be used by operators in the process of the real-time voltage/reactive power control in both normal and emergency operating states.

Bjelogrlic, M.; Babic, B.S. (Electric Power Board of Serbia, Belgrade (YU)); Calovic, M.S. (Dept. of Electrical Engineering, University of Belgrade, Belgrade (YU)); Ristanovic, P. (Institute Nikola Tesla, Belgrade (YU))

1990-11-01

284

Power system voltage stability and agent based distribution automation in smart grid  

NASA Astrophysics Data System (ADS)

Our interconnected electric power system is presently facing many challenges that it was not originally designed and engineered to handle. The increased inter-area power transfers, aging infrastructure, and old technologies, have caused many problems including voltage instability, widespread blackouts, slow control response, among others. These problems have created an urgent need to transform the present electric power system to a highly stable, reliable, efficient, and self-healing electric power system of the future, which has been termed "smart grid". This dissertation begins with an investigation of voltage stability in bulk transmission networks. A new continuation power flow tool for studying the impacts of generator merit order based dispatch on inter-area transfer capability and static voltage stability is presented. The load demands are represented by lumped load models on the transmission system. While this representation is acceptable in traditional power system analysis, it may not be valid in the future smart grid where the distribution system will be integrated with intelligent and quick control capabilities to mitigate voltage problems before they propagate into the entire system. Therefore, before analyzing the operation of the whole smart grid, it is important to understand the distribution system first. The second part of this dissertation presents a new platform for studying and testing emerging technologies in advanced Distribution Automation (DA) within smart grids. Due to the key benefits over the traditional centralized approach, namely flexible deployment, scalability, and avoidance of single-point-of-failure, a new distributed approach is employed to design and develop all elements of the platform. A multi-agent system (MAS), which has the three key characteristics of autonomy, local view, and decentralization, is selected to implement the advanced DA functions. The intelligent agents utilize a communication network for cooperation and negotiation. Communication latency is modeled using a user-defined probability density function. Failure-tolerant communication strategies are developed for agent communications. Major elements of advanced DA are developed in a completely distributed way and successfully tested for several IEEE standard systems, including: Fault Detection, Location, Isolation, and Service Restoration (FLISR); Coordination of Distributed Energy Storage Systems (DES); Distributed Power Flow (DPF); Volt-VAR Control (VVC); and Loss Reduction (LR).

Nguyen, Cuong Phuc

2011-12-01

285

Power Control of New Wind Power Generation System with Induction Generator Excited by Voltage Source Converter  

NASA Astrophysics Data System (ADS)

This paper investigates advantages of new combination of the induction generator for wind power and the power electronic equipment. Induction generator is popularly used for the wind power generation. The disadvantage of it is impossible to generate power at the lower rotor speed than the synchronous speed. To compensate this disadvantage, expensive synchronous generator with the permanent magnets is sometimes used. In proposed scheme, the diode rectifier is used to convert the real power from the induction generator to the intermediate dc voltage, while only the reactive power necessary to excite the induction generator is supplied from the voltage source converter (VSC). This means that the rating of the expensive VSC is minimized and total cost of the wind power generation system is decreased compared to the system with synchronous generator. Simulation study to investigate the control strategy of proposed system is performed. The results show the reduction of the VSC rating is prospective.

Morizane, Toshimitsu; Kimura, Noriyuki; Taniguchi, Katsunori

286

Ferroelectric Emission Cathodes for Low-Power Electric Propulsion  

NASA Technical Reports Server (NTRS)

Low- or no-flow electron emitters are required for low-power electric thrusters, spacecraft plasma contactors, and electrodynamic tether systems to reduce or eliminate the need for propellant/expellant. Expellant-less neutralizers can improve the viability of very low-power colloid thrusters, field emission electric propulsion devices, ion engines, Hall thrusters, and gridded vacuum arc thrusters. The NASA Glenn Research Center (GRC) is evaluating ferroelectric emission (FEE) cathodes as zero expellant flow rate cathode sources for the applications listed above. At GRC, low voltage (100s to approx. 1500 V) operation of FEE cathodes is examined. Initial experiments, with unipolar, bipolar, and RF burst applied voltage, have produced current pulses 250 to 1000 ns in duration with peak currents of up to 2 A at voltages at or below 1500 V. In particular, FEE cathodes driven by RF burst voltages from 1400 to 2000 V peak to peak, at burst frequencies from 70 to 400 kHz, emitted average current densities from 0.1 to 0.7 A/sq cm. Pulse repeatability as a function of input voltage has been initially established. Reliable emission has been achieved in air background at pressures as high as 10(exp -6) Torr.

Kovaleski, Scott D.; Burke, Tom (Technical Monitor)

2002-01-01

287

An earth-isolated optically coupled wideband high voltage probe powered by ambient light  

E-print Network

An earth-isolated optically coupled wideband high voltage probe powered by ambient light Xiang Zhai) An earth-isolated optically coupled wideband high voltage probe powered by ambient light Xiang Zhaia online 9 October 2012) An earth-isolated optically-coupled wideband high voltage probe has been developed

Bellan, Paul M.

288

Automated low-power technique exploiting multiple supply voltages applied to a media processor  

Microsoft Academic Search

This paper describes an automated design technique to reduce power by making use of two supply voltages. The technique consists of structure synthesis, placement and routing. The structure synthesizer clusters the gates off the critical paths so as to supply the reduced voltage to save power. The placement and routing tool assigns either the reduced voltage or the unreduced one

Kimiyoshi Usami; Kazutaka Nogami; Mutsunori Igarashi; Fumihiro Minami; Yukio Kawasaki; Takashi Ishikawa; Masahiro Kanazawa; Takahiro Aoki; Midori Takano; Chiharu Mizuno; Makoto Ichida; Shinji Sonoda; Makoto Takahashi; Naoyuki Hatanaka

1997-01-01

289

Automated low-power technique exploiting multiple supply voltages applied to a media processor  

Microsoft Academic Search

This paper describes an automated design technique to reduce power by making use of two supply voltages. The technique consists of structure synthesis, placement, and routing. The structure synthesizer clusters the gates off the critical paths so as to supply the reduced voltage to save power. The placement and routing tool assigns either the reduced voltage or the unreduced one

Kimiyoshi Usami; Mutsunori Igarashi; Fumihiro Minami; Takashi Ishikawa; M. Kanzawa; Makoto Ichida; Kazutaka Nogami

1998-01-01

290

Rotary-Atomizer Electric Power Generator  

NASA Astrophysics Data System (ADS)

We report experimental and theoretical results on a ballistic energy-conversion method based on a rotary atomizer working with a droplet acceleration-deceleration cycle. In a rotary atomizer, liquid is fed onto the center of a rotating flat surface, where it spreads out under the action of the centrifugal force and creates "atomized" droplets at its edge. The advantage of using a rotary atomizer is that the centrifugal force exerted on the fluid on a smooth, large surface is not only a robust form of acceleration, as it avoids clogging, but also easily allows high throughput, and produces high electrical power. We successfully demonstrate an output power of 4.9 mW and a high voltage up to 3120 V. At present, the efficiency of the system is still low (0.14%). However, the conversion mechanism of the system is fully interpreted in this paper, permitting a conceptual understanding of system operation and providing a roadmap for system optimization. This observation will open up a road for building power-generation systems in the near future.

Nguyen, Trieu; Tran, Tuan; de Boer, Hans; van den Berg, Albert; Eijkel, Jan C. T.

2015-03-01

291

Electric power annual 1997. Volume 1  

SciTech Connect

The Electric Power Annual presents a summary of electric power industry statistics at national, regional, and State levels. The objective of the publication is to provide industry decisionmakers, government policy-makers, analysts, and the general public with data that may be used in understanding US electricity markets. The Electric Power Annual is prepared by the Electric Power Division; Office of Coal, Nuclear, Electric and Alternate Fuels; Energy Information Administration (EIA); US Department of Energy. Volume 1 -- with a focus on US electric utilities -- contains final 1997 data on net generation and fossil fuel consumption, stocks, receipts, and cost; preliminary 1997 data on generating unit capability, and retail sales of electricity, associated revenue, and the average revenue per kilowatthour of electricity sold (based on a monthly sample: Form EIA-826, ``Monthly Electric Utility Sales and Revenue Report with State Distributions``). Additionally, information on net generation from renewable energy sources and on the associated generating capability is included in Volume 1 of the EPA.

NONE

1998-07-01

292

Architecture for a High-to-Medium-Voltage Power Converter  

NASA Technical Reports Server (NTRS)

A power converter now undergoing development is required to operate at a DC input potential ranging between 5.5 and 10 kV and a DC output potential of 400 V at a current up to 25 A. This power converter is also required to be sufficiently compact and reliable to fit and operate within the confines of a high-pressure case to be lowered to several miles (approx.5 km) below the surface of the ocean. The architecture chosen to satisfy these requirements calls for a series/ parallel arrangement of 48 high-frequency, pulse-width-modulation (PWM), transformer-isolation DC-to-DC power converter blocks. The input sides of the converter blocks would be connected in series so that the input potential would be divided among them, each of them being exposed to an input potential of no more than 10 kV/48 . 210 V. The series connection of inputs would also enforce a requirement that all the converter blocks operate at the same input current. The outputs of the converter blocks would be connected in a matrix comprising 6 parallel legs, each leg being a cascade of eight outputs wired in series (see figure). All the converter blocks would be identical within the tolerances of the values of their components. A single voltage feedback loop would regulate the output potential. All the converter blocks would be driven by the same PWM waveform generated by this feedback loop. The power transformer of each converter block would have a unity turns ratio and would be capable of withstanding as much as 10 kVDC between its primary and secondary windings. (Although, in general, the turns ratio could be different from unity, the simplest construction for minimizing leakage and maximizing breakdown voltage is attained at a turns ratio of unity.)

Vorpenian, Vatche

2008-01-01

293

An optimized low-power voltage controlled oscillator  

NASA Astrophysics Data System (ADS)

This paper presents an optimised low-power low-phase-noise Voltage Controlled Oscillator (VCO) for Bluetooth wireless applications. The system level design issues and tradeoffs related to Direct Conversion Receiver (DCR) and Low Intermediate Frequency (IF) architecture for Bluetooth are discussed. Subsequently, for a low IF architecture, the critical VCO performance parameters are derived from system specifications. The VCO presented in the paper is optimised by implementing a novel biasing circuit that employs two current mirrors, one at the top and the other one at the bottom of the cross-coupled complementary VCO, to give the exact replica of the current in both the arms of current mirror circuit. This approach, therefore, significantly reduces the system power consumption as well as improves the system performance. Results show that, the VCO consumes only 281μW of power at 2V supply. Its phase noise performance are -115dBc/Hz, -130dBc/Hz and -141dBc/Hz at the offset frequency of 1MHz, 3MHz and 5MHz respectively. Results indicate that 31% reduction in power consumption is achieved as compared to the traditional VCO design. These characteristics make the designed VCO a better candidate for Bluetooth wireless application where power consumption is the major issue.

Shah, Kriyang; Le, Hai Phuong; Singh, Jugdutt

2007-01-01

294

Electrical conductivity and current-voltage characteristics of alumina with or without neutron and electron irradiation  

E-print Network

Electrical conductivity and current-voltage characteristics of alumina with or without neutron±voltage (I±V) characteristics of single- and poly- crystal alumina have been carried out both in HFIR (high for non-ohmic behavior is discussed on the basis of the dierence of work function between electrode

Howlader, Matiar R

295

Design of insulated structure for load-ratio voltage power transformer by finite element method  

SciTech Connect

For improving insulated level of 220 kV load-ratio voltage power transformer, two-dimensional and three-dimensional electric fields around the shielding ring of the regulative winding in this transformer have been precisely calculated by the finite element method. The calculated results show that the field intensity at the oil-corner for the shielding ring with the traditional oil-corner design is too high to insure enough insulated level of this transformer. Two new shielding ring structures without oil-corner have been designed by using the finite element method. The maximum field intensity for each new design is reduced to 2.000 kV/mm from 2.633 kV/mm under 100 kV applied voltage.

Cui Xiang; Liu Jianxin; He Ronggui [North China Inst. of Electric Power, Hebei (China). Dept. of Electrical Engineering] [North China Inst. of Electric Power, Hebei (China). Dept. of Electrical Engineering; Xie Yucheng; Zhang Guoqiang; Yang Chunping [Baoding Transformer Works, Hebei (China). High Voltage Lab.] [Baoding Transformer Works, Hebei (China). High Voltage Lab.

1994-09-01

296

Acute ischemic stroke in low-voltage electrical injury: A case report  

PubMed Central

Background: Acute stroke is not a common complication of electrical injury, and only a few cases of acute stroke have been reported for lightning or high-voltage injuries. Case Report: We present the case of a man who suffered from a low-voltage electrical injury followed by ischemic stroke. Magnetic resonance angiography showed segmental narrowing of the right internal carotid artery and right middle cerebral artery. The patient underwent thrombolytic therapy and catheter-assisted angioplasty. The low-voltage current-induced vasospasm rather than direct vascular injury, and this may explain why the intracranial defect occurred away from the electrical current pathway. Conclusion: Electric shock injury with low-voltage alternating currents and prolonged contact period may cause ischemic stroke. PMID:21206535

Huan-Jui, Yeh; Chih-Yang, Liu; Huei-Yu, Lo; Po-Chih, Chen

2010-01-01

297

On the Cause and Control of Residual Voltage Generated by Electrical Stimulation of Neural Tissue  

E-print Network

. Residual voltage can cause polarization of the electrode and pose a problem for safe electrical stimulation that is modeled by a charge-transfer resistance Rct. The mass transport limitations of ions in the electrolyte

Kelly, Shawn K.

298

ACEEE Int. J. on Electrical and Power Engineering, Vol. 01, No. 03, Dec 2010 2010 ACEEE  

E-print Network

controlled drives employ mostly a Voltage Source Inverter (VSI) to control the motor armature, despite@tce.edu Abstract In today s high-power electrical drives using vector controlled induction machines, voltage source inverters (VSI) based on PWM technology and current source inverters (CSI) based on based on PWM technology

Paris-Sud XI, Université de

299

Mine electrical power systems. Transients protection, reliability investigation, and safety testing of mine electrical power systems. Volume V--periodic inspection of mine electrical power systems. Open file report (final) 24 Jun 74-15 aug 78  

Microsoft Academic Search

This report presents the results of an investigation into the feasibility of periodically measuring parameters of the insulation for a mine electrical power system to detect incipient faults. The variety of insulation parameters evaluated included insulation resistance, dissipation factor, power factor (versus applied voltage), current harmonics, leakage current, infrared radiation, as well as certain circuit breaker parameters and tests. To

E. K. Stanek; M. M. Hassan; Y. C. Chou; H. Shamash

1979-01-01

300

Reduction in overvoltages and dynamic power losses in power switches of multilevel voltage inverters  

NASA Astrophysics Data System (ADS)

A number of the circuit and design decisions that provide a reduction in overvoltage and dynamic power losses in power switches of multilevel voltage inverters with clamping diodes is considered. It is shown that the integral or unpackaged version is the most effective method for a reduction in the stray inductance in the multilevel circuit, which is the general cause for occurrence of dynamic overvoltage. To reduce dynamic losses of power, a method for resonant commutation on fronts, which provides commutation of switches in the multilevel circuit at zero voltage (SZV) and zero current (SZC), is proposed. The resonant switching method as applied to the multilevel circuit simultaneously solves a problem of dynamic overvoltage by means of limitation for the rate of voltage rise in the SZV mode or the mode of preliminary fault of energy stored in the inductance of the switching circuit in the SZC mode.

Voronin, P. A.; Voronin, I. P.; Panfilov, D. I.; Rozhkov, D. V.

2014-12-01

301

Multi-Objective Differential Evolution for Voltage Security Constrained Optimal Power Flow in Deregulated Power Systems  

NASA Astrophysics Data System (ADS)

Voltage stability is an important issue in the planning and operation of deregulated power systems. The voltage stability problems is a most challenging one for the system operators in deregulated power systems because of the intense use of transmission line capabilities and poor regulation in market environment. This article addresses the congestion management problem avoiding offline transmission capacity limits related to voltage stability by considering Voltage Security Constrained Optimal Power Flow (VSCOPF) problem in deregulated environment. This article presents the application of Multi Objective Differential Evolution (MODE) algorithm to solve the VSCOPF problem in new competitive power systems. The maximum of L-index of the load buses is taken as the indicator of voltage stability and is incorporated in the Optimal Power Flow (OPF) problem. The proposed method in hybrid power market which also gives solutions to voltage stability problems by considering the generation rescheduling cost and load shedding cost which relieves the congestion problem in deregulated environment. The buses for load shedding are selected based on the minimum eigen value of Jacobian with respect to the load shed. In the proposed approach, real power settings of generators in base case and contingency cases, generator bus voltage magnitudes, real and reactive power demands of selected load buses using sensitivity analysis are taken as the control variables and are represented as the combination of floating point numbers and integers. DE/randSF/1/bin strategy scheme of differential evolution with self-tuned parameter which employs binomial crossover and difference vector based mutation is used for the VSCOPF problem. A fuzzy based mechanism is employed to get the best compromise solution from the pareto front to aid the decision maker. The proposed VSCOPF planning model is implemented on IEEE 30-bus system, IEEE 57 bus practical system and IEEE 118 bus system. The pareto optimal front obtained from MODE is compared with reference pareto front and the best compromise solution for all the cases are obtained from fuzzy decision making strategy. The performance measures of proposed MODE in two test systems are calculated using suitable performance metrices. The simulation results show that the proposed approach provides considerable improvement in the congestion management by generation rescheduling and load shedding while enhancing the voltage stability in deregulated power system.

Roselyn, J. Preetha; Devaraj, D.; Dash, Subhransu Sekhar

2013-11-01

302

Reducing the Vulnerability of Electric Power Grids to Terrorist Attacks  

SciTech Connect

This report describes the development of a cascading outage analyzer that, given an initial disturbance on an electric power system, checks for thermal overloads, under-frequency and over-frequency conditions, and under-voltage conditions that would result in removal of elements from the system. The analyzer simulates the successive tripping of elements due to protective actions until a post-event steady state or a system blackout is reached.

Ross Baldick; Thekla Boutsika; Jin Hur; Manho Joung; Yin Wu; Minqi Zhong

2009-01-31

303

ROSET. Solar Thermal Electric Power Simulation  

Microsoft Academic Search

ROSET consists of five programs to calculate the energy output of a solar thermal electric power system. The ROSET programs provide two distinct functions. The first four (WTPREAD, FIELD, POWERT, and POWERE) use hourly weather data for a year to calculate hourly electric energy output for a solar thermal system. The last program (HISTO) uses one or more electric energy

1982-01-01

304

A market mechanism for electric power transmission  

Microsoft Academic Search

As competition is introduced into the electric power industry, access and pricing policy for transmission will play a pivotal role in shaping future market structure and performance. The externalities associated with the loop flow phenomenon in an electric power network constitute a significant barrier to the formation of efficient markets for electricity and transmission services. In this paper, we present

Hung-Po Chao; Stephen Peck

1996-01-01

305

High voltage technology for a Traveling Wave Tube Electronic Power Conditioner (TWT-EPC) for a Synthetic Aperture Radar (SAR)  

NASA Astrophysics Data System (ADS)

A satellite-borne synthetic aperture radar system with an output power of 5 to 20 kW was studied to determine electronic power conditioning (EPC) requirements. The EPC technology is described. The selection of the insulating materials, the test procedures, and switching principles for an emitting amplifier tube are reviewed. The electrical and mechanical load limits and the thermal criteria relative to the aperture width and voltage are presented. The insulating systems and partial discharge in ac and dc were tested, and acceleration tests performed. A power section comprising an inverter, a high voltage transformer and rectifier and a capacitor bank was built and tested in thermal vacuum under various operating conditions. It confirms the reliability of the high voltage technology and its applicability in the design of flight hardware.

Geissler, K. H.; Bernhard, R.; Seeliger, R.

1985-12-01

306

Advanced medium-voltage bidirectional dc-dc conversion systems for future electric energy delivery and management systems  

NASA Astrophysics Data System (ADS)

The distributed renewable energy generation and utilization are constantly growing, and are expected to be integrated with the conventional grid. The growing pressure for innovative solutions will demand power electronics to take an even larger role in future electric energy delivery and management systems, since power electronics are required for the conversion and control of electric energy by most dispersed generation systems Furthermore, power electronics systems can provide additional intelligent energy management, grid stability and power quality capabilities. Medium-voltage isolated dc-dc converter will become one of the key interfaces for grid components with moderate power ratings. To address the demand of medium voltage (MV) and high power capability for future electric energy delivery and management systems, the power electronics community and industry have been reacting in two different ways: developing semiconductor technology or directly connecting devices in series/parallel to reach higher nominal voltages and currents while maintaining conventional converter topologies; and by developing new converter topologies with traditional semiconductor technology, known as multilevel converters or modular converters. The modular approach uses the well-known, mature, and cheaper power semiconductor devices by adopting new converter topologies. The main advantages of the modular approach include: significant improvement in reliability by introducing desired level of redundancy; standardization of components leading to reduction in manufacturing cost and time; power systems can be easily reconfigured to support varying input-output specifications; and possibly higher efficiency and power density of the overall system. Input-series output-parallel (ISOP) modular configuration is a good choice to realize MV to low voltage (LV) conversion for utility application. However, challenges still remain. First of all, for the high-frequency MV utility application, the low switching loss and conduction loss are must-haves for high efficiency, while bidirectional power flow capability is a must for power management requirement. To address the demand, the phase-shift dual-halfbridge (DHB) is proposed as the constituent module of ISOP configuration for MV application. The proposed ISOP DHB converter employs zero-voltage-switching (ZVS) technique combined with LV MOSFETs to achieve low switching and conduction losses under high frequency operation, and therefore high efficiency and high power density, and bidirectional power flow as well. Secondly, a large load range of high efficiency is desired rather than only a specific load point due to the continuous operation and large load variation range of utility application, which is of high importance because of the rising energy cost. This work proposes a novel DHB converter with an adaptive commutation inductor. By utilizing an adaptive inductor as the main energy transfer element, the output power can be controlled by not only the phase shift but also the commutation inductance, which allows the circulating energy to be optimized for different load conditions to maintain ZVS under light load conditions and minimize additional conduction losses under heavy load conditions as well. As a result, the efficiency at both light and heavy load can be significantly improved compared with the conventional DHB converter, and therefore extended high-efficiency range can be achieved. In addition, current stress of switch devices can be reduced. The theoretical analysis is presented and validated by the experimental results on a 50 kHz, 1 kW dc-dc converter module. Thirdly, input-voltage sharing and output-current sharing are critical to assure the advantages of the ISOP modular configuration. To solve this issue, an identically distributed control scheme is proposed in this work. The proposed control scheme, using only one distributed voltage loop to realize both input-voltage and output-current sharing, provides plug-and-play capability, possible high-level fault tolerance, and easy implementatio

Fan, Haifeng

2011-12-01

307

Consumption of the electric power inside silent discharge reactors  

NASA Astrophysics Data System (ADS)

An experimental study was made in this paper to investigate the relation between the places of the dielectric barriers, which cover the surfaces of the electrodes in the coaxial cylindrical reactors, and the rate of change of the electric power that is consumed in forming silent discharges. Therefore, silent discharges have been formed inside three coaxial cylindrical reactors. The dielectric barriers in these reactors were pasted on both the internal surface of the outer electrode in the first reactor and the external surface of the inner electrode in the second reactor as well as the surfaces of the two electrodes in the third reactor. The reactor under study has been fed by atmospheric air that flowed inside it with a constant rate at normal temperature and pressure, in parallel with the application of a sinusoidal ac voltage between the electrodes of the reactor. The electric power consumed in forming the silent discharges inside the three reactors was measured as a function of the ac peak voltage. The validity of the experimental results was investigated by applying Manley's equation on the same discharge conditions. The results have shown that the rate of consumption of the electric power relative to the ac peak voltage per unit width of the discharge gap improves by a ratio of either 26.8% or 80% or 128% depending on the places of the dielectric barriers that cover the surfaces of the electrodes inside the three reactors.

Yehia, Ashraf

2015-01-01

308

Electric force microscopy testing of digital voltages using the heterodyne mixing technique  

NASA Astrophysics Data System (ADS)

Electric force microscopy (EFM) testing is a promising test technique for function and failure analysis of integrated circuits, especially in the design phase. It enables contactless, chip internal voltage measurements with simultaneous high temporal and high spatial resolution. Up to now, for EFM-testing of periodic digital voltages the sampling technique was used. Another technique - the heterodyne mixing technique - allows fast two-dimensional voltage contrast measurements, which cannot be done using the sampling technique. Thus, in this paper the suitability of the heterodyne mixing technique for the measurement of periodic digital voltages is investigated.

Behnke, U.; Klümper, D.; Mertin, W.

2003-03-01

309

Electrical power requirements analysis. Single failure tolerant entry  

NASA Technical Reports Server (NTRS)

The results of an analysis of the orbiter electrical power system for the case of a single failure tolerant (SFT) entry are presented. The analysis was performed using the shuttle electrical power system analysis computer program. It was performed to permit assessment of the capability of the orbiter systems to support the proposed entry configuration and to provide the data necessary to identify potential constraints and limitations. Three contingency modes have been identified which would require an SFT entry. This analysis addresses an SFT entry resulting from the loss of two fuel cell powerplants, while on orbit. The results of the analysis indicate that, even under near optimum conditions, the fuel cell power demand will exceed the tested operating capacity of 16 kw, and that various electrical components may experience voltages below 24 VDC.

Pipher, M. D.; Green, P. A.; Wolfgram, D. F.

1977-01-01

310

Pattern recognition for electric power system protection  

NASA Astrophysics Data System (ADS)

The objective of this research is to demonstrate pattern recognition tools such as decision trees (DTs) and neural networks that will improve and automate the design of relay protection functions in electric power systems. Protection functions that will benefit from the research include relay algorithms for high voltage transformer protection (TP) and for high impedance fault (HIF) detection. A methodology, which uses DTs and wavelet analysis to distinguish transformer internal faults from other conditions that are easily mistaken for internal faults, has been developed. Also, a DT based solution is proposed to discriminate HIFs from normal operations that may confuse relays. Both methods have been verified with simulation data generated by the Electromagnetic Transients Program. Compared with traditional methods, both show better performance. After being trained with a large number of carefully selected features, the desired DTs can obtain an accuracy of greater than 95%. Further, no special equipment is necessary; the DT-based controller only needs the standard relay input signals sampled at 1920 Hz. So far, no one has applied the same methodologies to solve these problems. Even though some future work with experimental data is needed to make the methods more convincing for utilities, the research has already shown that pattern recognition is a promising direction in developing power system protection algorithms.

Sheng, Yong

2002-11-01

311

FPGA Based Voltage & Current Dual Drive System for High Frame Rate Electrical Impedance Tomography.  

PubMed

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 frequencydifference 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 signalaveraging factor of 8, the DAQ frame rate at 100 kHz exceeded 110 frames s-1, and SNR exceeded 90 dB across the spectrum. Reciprocity error was found to be <1% for frequencies up to 1 MHz. Static imaging experiments were performed on a highconductivity 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

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

2014-11-01

312

A Multiphase, Modular, Bidirectional, Triple-Voltage DC-DC Converter Power Systems  

SciTech Connect

Electrical power systems in future hybrid and fuel cell vehicles may employ three voltage [14 V, 42 V, and high voltage (HV)] nets. These will be necessary to accommodate existing 14-V loads as well as efficiently handle new heavy loads at the 42-V net and a traction drive on the HV bus. A low-cost DC-DC converter was proposed for connecting the three voltage nets. It minimizes the number of switches and their associated gate driver components by using two half-bridges and a high-frequency transformer. Another salient feature is that the half bridge on the 42-V bus is also utilized to provide the 14-V bus by operating at duty ratios around an atypical value of 1/3. Moreover, it makes use of the parasitic capacitance of the switches and the transformer leakage inductance for soft switching. The use of half bridges makes the topology well suited for interleaved multiphase modular configurations as a means to increase the power level because the capacitor legs can be shared. This paper presents simulation and experimental results on an interleaved two-phase arrangement rated at 4.5 kW. Also discussed are the benefits of operating with an atypical duty ratio on the transformer and a preferred multiphase configuration to minimize capacitor ripple currents.

Su, Gui-Jia [ORNL; Tang, Lixin [ORNL

2008-01-01

313

Critical Electric Power Issues in Pennsylvania  

E-print Network

Critical Electric Power Issues in Pennsylvania: Transmission, Distributed Generation and Continuing that exist in Pennsylvania. The power industry in the Commonwealth is the second leading generator of electric power in the nation, and Pennsylvania is home to abundant indigenous fuel sources such as wind

314

A Novel Electrical Insulating Material for 275 kV High-Voltage HTS Cable with Low Dielectric Loss  

NASA Astrophysics Data System (ADS)

In the case of high temperature superconducting (HTS) power transmission cables at high voltage operation, the electrical insulation technique in consideration of the dielectric loss reduction becomes crucial. In this paper, we focused on a Tyvek/polyethylene (PE) sheet, instead of the conventional polypropylene laminated paper (PPLP). We obtained the dielectric characteristics (epsilonr, tan?) and partial discharge inception strength (PDIE) of PPLP, Tyvek and Tyvek/PE. We pointed out that the dielectric loss of 275 kV HTS cable with Tyvek/PE insulation will be reduced to 21 % of that with PPLP, and the total electrical loss including the AC loss will be reduced to 41 %.

Hayakawa, N.; Nishimachi, S.; Maruyama, O.; Ohkuma, T.; Liu, J.; Yagi, M.

2014-05-01

315

Electrical power technology for robotic planetary rovers  

NASA Technical Reports Server (NTRS)

Power technologies which will enable a range of robotic rover vehicle missions by the end of the 1990s and beyond are discussed. The electrical power system is the most critical system for reliability and life, since all other on board functions (mobility, navigation, command and data, communications, and the scientific payload instruments) require electrical power. The following are discussed: power generation, energy storage, power management and distribution, and thermal management.

Bankston, C. P.; Shirbacheh, M.; Bents, D. J.; Bozek, J. M.

1993-01-01

316

High-voltage, high-power, solid-state remote power controllers for aerospace applications  

NASA Technical Reports Server (NTRS)

Two general types of remote power controller (RPC) that combine the functions of a circuit breaker and a switch were developed for use in direct-current (dc) aerospace systems. Power-switching devices used in these designs are the relatively new gate-turnoff thyristor (GTO) and poweer metal-oxide-semiconductor field-effect transistors (MOSFET). The various RPC's can switch dc voltages to 1200 V and currents to 100 A. Seven different units were constructed and subjected to comprehensive laboratory and thermal vacuum testing. Two of these were dual units that switch both positive and negative voltages simultaneously. The RPC's using MOSFET's have slow turnon and turnoff times to limit voltage spiking from high di/dt. The GTO's have much faster transition times. All RPC's have programmable overload tripout and microsecond tripout for large overloads. The basic circuits developed can be used to build switchgear limited only by the ratings of the switching device used.

Sturman, J. C.

1985-01-01

317

Design of high-voltage, high-power, solid state remote power controllers for aerospace applications  

NASA Astrophysics Data System (ADS)

Two general types of remote power controllers (RPC's), which combine the functions of a circuit breaker and a switch, were developed for use in dc aerospace systems. Power-switching devices used in the designs are the gate-turnoff thyristor (GTO) and MOSFET. The RPC's can switch dc voltages to 1200 V and currents to 1000 A. Seven different units were constructed and subjected to laboratory and thermal vacuum testing. Two of these were dual units that switch both positive and negative voltages simultaneously. The RPC's using MOSFET's have slow turnon and turnoff times which limit surge currents and voltage spiking from high di/dt. The GTO's have much faster transition times. All RPC's have programmable overload tripout proportional to I sq T and microsecond tripout for large overloads.

Sturman, J. C.

1985-05-01

318

Design of high-voltage, high-power, solid state remote power controllers for aerospace applications  

NASA Technical Reports Server (NTRS)

Two general types of remote power controllers (RPC's), which combine the functions of a circuit breaker and a switch, were developed for use in dc aerospace systems. Power-switching devices used in the designs are the gate-turnoff thyristor (GTO) and MOSFET. The RPC's can switch dc voltages to 1200 V and currents to 1000 A. Seven different units were constructed and subjected to laboratory and thermal vacuum testing. Two of these were dual units that switch both positive and negative voltages simultaneously. The RPC's using MOSFET's have slow turnon and turnoff times which limit surge currents and voltage spiking from high di/dt. The GTO's have much faster transition times. All RPC's have programmable overload tripout proportional to I sq T and microsecond tripout for large overloads.

Sturman, J. C.

1985-01-01

319

Solar energy thermally powered electrical generating system  

NASA Technical Reports Server (NTRS)

A thermally powered electrical generating system for use in a space vehicle is disclosed. The rate of storage in a thermal energy storage medium is controlled by varying the rate of generation and dissipation of electrical energy in a thermally powered electrical generating system which is powered from heat stored in the thermal energy storage medium without exceeding a maximum quantity of heat. A control system (10) varies the rate at which electrical energy is generated by the electrical generating system and the rate at which electrical energy is consumed by a variable parasitic electrical load to cause storage of an amount of thermal energy in the thermal energy storage system at the end of a period of insolation which is sufficient to satisfy the scheduled demand for electrical power to be generated during the next period of eclipse. The control system is based upon Kalman filter theory.

Owens, William R. (Inventor)

1989-01-01

320

Electric Power: Decisions for the Future.  

ERIC Educational Resources Information Center

Reviews the past 25 years of electricity consumption in the United States and considers the implications for the near future. Discusses strategies for energy conservation and provides a student activity for measuring and conserving electric power. (Author/JOW)

Cardon, Phillip L.; Preston, John

2003-01-01

321

Electric power annual 1997. Volume 2  

SciTech Connect

The Electric Power Annual 1997, Volume 2 contains annual summary statistics at national, regional, and state levels for the electric power industry, including information on both electric utilities and nonutility power producers. Included are data for electric utility retail sales of electricity, associated revenue, and average revenue per kilowatthour of electricity sold; financial statistics; environmental statistics; power transactions; and demand-side management. Also included are data for US nonutility power producers on installed capacity; gross generation; emissions; and supply and disposition of energy. The objective of the publication is to provide industry decisionmakers, government policymakers, analysts, and the general public with historical data that may be used in understanding US electricity markets. 15 figs., 62 tabs.

NONE

1998-10-01

322

Electromagnetic Noise Superimposed on the Electric Power Supply to Electronic Medical Equipment  

Microsoft Academic Search

The use of mobile medical electronic equipment driven at low electric power outputs has progressed rapidly in recent years. Voltage change and noise superimposed on the power supply could create obstacles to the operation of medical electronic equipment. We observed the quality of the power supply of medical electronic equipment in a university hospital, and found approximately 5% distortion on

Eisuke Hanada; Kyoko Takano; Kenji Kodama

2003-01-01

323

Automatic voltage imbalance detector  

DOEpatents

A device for indicating and preventing damage to voltage cells such as galvanic cells and fuel cells connected in series by detecting sequential voltages and comparing these voltages to adjacent voltage cells. The device is implemented by using operational amplifiers and switching circuitry is provided by transistors. The device can be utilized in battery powered electric vehicles to prevent galvanic cell damage and also in series connected fuel cells to prevent fuel cell damage.

Bobbett, Ronald E. (Los Alamos, NM); McCormick, J. Byron (Los Alamos, NM); Kerwin, William J. (Tucson, AZ)

1984-01-01

324

Voltage Control of Distribution Networks with Distributed Generation using Reactive Power  

E-print Network

Voltage Control of Distribution Networks with Distributed Generation using Reactive Power levels. However, with significant penetration of distributed generation, the power flows may become with power flows and voltages determined by the generation as well as load. Hence, there are dramatic changes

Pota, Himanshu Roy

325

Compact portable electric power sources  

SciTech Connect

This report provides an overview of recent advances in portable electric power source (PEPS) technology and an assessment of emerging PEPS technologies that may meet US Special Operations Command`s (SOCOM) needs in the next 1--2- and 3--5-year time frames. The assessment was performed through a literature search and interviews with experts in various laboratories and companies. Nineteen PEPS technologies were reviewed and characterized as (1) PEPSs that meet SOCOM requirements; (2) PEPSs that could fulfill requirements for special field conditions and locations; (3) potentially high-payoff sources that require additional R and D; and (4) sources unlikely to meet present SOCOM requirements. 6 figs., 10 tabs.

Fry, D.N.; Holcomb, D.E.; Munro, J.K.; Oakes, L.C.; Matson, M.J.

1997-02-01

326

Wind wheel electric power generator  

NASA Technical Reports Server (NTRS)

Wind wheel electric power generator apparatus includes a housing rotatably mounted upon a vertical support column. Primary and auxiliary funnel-type, venturi ducts are fixed onto the housing for capturing wind currents and conducting to a bladed wheel adapted to be operatively connected with the generator apparatus. Additional air flows are also conducted onto the bladed wheel; all of the air flows positively effecting rotation of the wheel in a cumulative manner. The auxiliary ducts are disposed at an acute angle with respect to the longitudinal axis of the housing, and this feature, together with the rotatability of the housing and the ducts, permits capture of wind currents within a variable directional range.

Kaufman, J. W. (inventor)

1980-01-01

327

Measuring Power Flow in Electric Vehicles  

NASA Technical Reports Server (NTRS)

Instrument accommodates fast rise and fall times of waveforms characteristic of modern, efficient power controllers. Power meter multiplies analog signals proportional to voltage and current, and converts resulting signal to frequency. Two mechanical counters provided: one for charging, one for discharging.

Griffin, Daniel C., Jr; Wiker, G. A.

1983-01-01

328

Electric power substation capital costs  

SciTech Connect

The displacement or deferral of substation equipment is a key benefit associated with several technologies that are being developed with the support of the US Department of Energy`s Office of Utility Technologies. This could occur, for example, as a result of installing a distributed generating resource within an electricity distribution system. The objective of this study was to develop a model for preparing preliminary estimates of substation capital costs based on rudimentary conceptual design information. The model is intended to be used by energy systems analysts who need ``ballpark`` substation cost estimates to help establish the value of advanced utility technologies that result in the deferral or displacement of substation equipment. This cost-estimating model requires only minimal inputs. More detailed cost-estimating approaches are recommended when more detailed design information is available. The model was developed by collecting and evaluating approximately 20 sets of substation design and cost data from about 10 US sources, including federal power marketing agencies and private and public electric utilities. The model is principally based on data provided by one of these sources. Estimates prepared with the model were compared with estimated and actual costs for the data sets received from the other utilities. In general, good agreement (for conceptual level estimating) was found between estimates prepared with the cost-estimating model and those prepared by the individual utilities. Thus, the model was judged to be adequate for making preliminary estimates of typical substation costs for US utilities.

Dagle, J.E.; Brown, D.R.

1997-12-01

329

Electrical power generation by mechanically modulating electrical double layers.  

PubMed

Since Michael Faraday and Joseph Henry made their great discovery of electromagnetic induction, there have been continuous developments in electrical power generation. Most people today get electricity from thermal, hydroelectric, or nuclear power generation systems, which use this electromagnetic induction phenomenon. Here we propose a new method for electrical power generation, without using electromagnetic induction, by mechanically modulating the electrical double layers at the interfacial areas of a water bridge between two conducting plates. We find that when the height of the water bridge is mechanically modulated, the electrical double layer capacitors formed on the two interfacial areas are continuously charged and discharged at different phases from each other, thus generating an AC electric current across the plates. We use a resistor-capacitor circuit model to explain the results of this experiment. This observation could be useful for constructing a micro-fluidic power generation system in the near future. PMID:23403587

Moon, Jong Kyun; Jeong, Jaeki; Lee, Dongyun; Pak, Hyuk Kyu

2013-01-01

330

Processing of thermionic power on an electrically propelled spacecraft  

NASA Technical Reports Server (NTRS)

A study to define the power processing equipment required between a thermionic reactor and an array of mercury-ion thrusters for a nuclear electric propulsion system is reported. Observations and recommendations that resulted from this study were: (1) the preferred thermionic-fuel-element source voltages are 23 V or higher; (2) transistor characteristics exert a strong effect on power processor mass; (3) the power processor mass could be considerably reduced should the magnetic materials that exhibit low losses at high frequencies, that have a high Curie point, and that can operate at 15 to 20 kG become avaliable; (4) electrical component packaging on the radiator could reduce the area that is sensitive to meteoroid penetration, thereby reducing the meteoroid shielding mass requirement; (5) an experimental model of the power processor design should be built and tested to verify the efficiencies, masses, and all the automatic operational aspects of the design.

Macie, T. W.

1973-01-01

331

Numerical determination of electric field induced currents on human body standing under a high voltage transmission line  

Microsoft Academic Search

In this paper, biological effects of high voltage transmission line electric field on biological systems especially on a grounded human body standing under a high voltage transmission line have been studied. The electric field distribution on a human body standing underneath extra high voltage overhead transmission lines has been calculated by using Boundary element method (BEM). Induced currents and current

S. M. El-Makkawy

2007-01-01

332

Predicting market power in wholesale electricity markets  

E-print Network

Predicting market power in wholesale electricity markets#3; David M Newbery Faculty of Economics, University of Cambridge August 26, 2008 Abstract The traditional measure of market power is the HHI, which gives implausible results given the low... elasticity of demand in electricity spot markets, unless it is adapted to take account of contracting. In its place the Residual Supply Index has been proposed as a more suitable index to measure potential market power in electricity markets, notably...

Newbery, David

333

Electric power annual 1995. Volume I  

SciTech Connect

The Electric Power Annual presents a summary of electric power industry statistics at national, regional, and State levels. The objective of the publication is to provide industry decisionmakers, government policymakers, analysts, and the general public with data that may be used in understanding U.S. electricity markets. The Electric Power Annual is prepared by the Coal and Electric Data and Renewables Division; Office of Coal, Nuclear, Electric and Alternate Fuels; Energy Information Administration (EIA); U.S. Department of Energy. In the private sector, the majority of the users of the Electric Power Annual are researchers and analysts and, ultimately, individuals with policy- and decisionmaking responsibilities in electric utility companies. Financial and investment institutions, economic development organizations interested in new power plant construction, special interest groups, lobbyists, electric power associations, and the news media will find data in the Electric Power Annual useful. In the public sector, users include analysts, researchers, statisticians, and other professionals with regulatory, policy, and program responsibilities for Federal, State, and local governments. The Congress and other legislative bodies may also be interested in general trends related to electricity at State and national levels. Much of the data in these reports can be used in analytic studies to evaluate new legislation. Public service commissions and other special government groups share an interest in State-level statistics. These groups can also compare the statistics for their States with those of other jurisdictions.

NONE

1996-07-01

334

The Constant Voltage Transformer (CVT) for Mitigating Effects of Voltage Sags on Industrial Equipment  

E-print Network

) an increase in loads that use power electronics in some type of power conversion configuration [1][2]. This paper presents applications of the constant-voltage transformer (CVT) for mitigating the effects of electric service voltage sags on industrial...

Ferraro, R. J.; Osborne, R.; Stephens, R.

335

Module Five: Relationships of Current, Voltage, and Resistance; Basic Electricity and Electronics Individualized Learning System.  

ERIC Educational Resources Information Center

This module covers the relationships between current and voltage; resistance in a series circuit; how to determine the values of current, voltage, resistance, and power in resistive series circuits; the effects of source internal resistance; and an introduction to the troubleshooting of series circuits. This module is divided into five lessons:…

Bureau of Naval Personnel, Washington, DC.

336

Power system characteristics for more electric aircraft  

NASA Technical Reports Server (NTRS)

It should not be suprising that more electric aircraft must meet significantly more difficult electrical power system requirements than were considereed when today's power distribution systems were being developed. Electric power, no longer a secondary system, will become a critical element of the primary control system. Functional reliability requiirements will be extremely stringent and can only be met by controlling element redundancy within a distributed power system. Existing electrical systems were not developed to have both the power system and the control/sensing elements distributed and yet meet the requirements of lighting tolerance and high intensity radio frequency (HIRF). In addition, the operation of electric actuators involves high transient loading and reverse energy flows. Such phenomena were also not anticipated when power quality was specified for either 270 vdc or 400 Hertz ac power systems. This paper will expand upon the issues and discuss some of the technologies involved in their resolution.

Hansen, Irving G.

1993-01-01

337

Voltage Oscillations in Power Distribution Networks in the Presence of DFIGs and Induction Motor Loads  

E-print Network

Voltage Oscillations in Power Distribution Networks in the Presence of DFIGs and Induction Motor, DFIG, eigenvalue, in- duction motor, small-signal stability. I. INTRODUCTION Distributed generation (DG

Pota, Himanshu Roy

338

Computer Power. Part 2: Electrical Power Problems and Their Amelioration.  

ERIC Educational Resources Information Center

Describes electrical power problems that affect computer users, including spikes, sags, outages, noise, frequency variations, and static electricity. Ways in which these problems may be diagnosed and cured are discussed. Sidebars consider transformers; power distribution units; surge currents/linear and non-linear loads; and sizing the power

Price, Bennett J.

1989-01-01

339

High voltage bipolar mode SIT with low power loss  

Microsoft Academic Search

The characteristics of a novel 500-V, 200-A bipolar-mode SIT (static induction transistor) are reported. The sustaining voltage is the key aspect of the voltage capability under an inductive load switching; it can be improved without affecting the current gain or the switching speed. Reduction of the gate resistance is effective in raising the sustaining voltage. The current gain is improved

H. Takagi; H. Kawauchi; T. Yoshida; S. Miura; H. Ito; H. Tadano

1993-01-01

340

Performance Analysis of a Hybrid Asymmetric Multilevel Inverter for High Voltage Active Power Filter Applications  

E-print Network

voltage-source inverters connected in series (known as cascaded hybrid asymmetric multilevel inverter, especially for motor drive applications and reactive power compensation. Multilevel voltage-source inverters). Each cell is composed by a dc capacitor and a full­bridge single­phase PWM voltage­source inverter

Catholic University of Chile (Universidad Católica de Chile)

341

Voltage control in power system using expert system based on SCADA system  

Microsoft Academic Search

This paper presents the type of expert system for controlling the 22 kV voltage levels of a power system in the northern region of Thailand based on the SCADA system. At present, for the operation, the operators have to make decisions by their knowledge and experience to control the voltage. This expert system is obtained for alleviation of voltage violation

C. Pimpa; S. Premrudeepreechacharn

2002-01-01

342

Voltage control of distribution networks with distributed generation using reactive power compensation  

Microsoft Academic Search

Voltage profile of distribution networks with distributed generation are affected significantly due to the integration of distributed generation (DG) on it. This paper presents a way to control voltage of distribution networks with DG using reactive power compensation approach. In this paper, the voltage control approach is shown based on the worst case scenario of the network. To keep the

M. A. Mahmud; M. J. Hossain; H. R. Pota; A. B. M. Nasiruzzaman

2011-01-01

343

Electrical detection of spin pumping: dc voltage generated by ferromagnetic resonance at ferromagnet/nonmagnet contact  

E-print Network

Electrical detection of spin pumping: dc voltage generated by ferromagnetic resonance We describe electrical detection of spin pumping in metallic nanostructures. In the spin pumping effect, a precessing ferromagnet attached to a normal metal acts as a pump of spin-polarized current

van der Wal, Caspar H.

344

Power quality load management for large spacecraft electrical power systems  

NASA Technical Reports Server (NTRS)

In December, 1986, a Center Director's Discretionary Fund (CDDF) proposal was granted to study power system control techniques in large space electrical power systems. Presented are the accomplishments in the area of power system control by power quality load management. In addition, information concerning the distortion problems in a 20 kHz ac power system is presented.

Lollar, Louis F.

1988-01-01

345

Design, Construction and Testing of a Voltage-based Maximum Power Point Tracker (VMPPT) for Small Satellite Power Supply  

Microsoft Academic Search

It is shown that at maximum power, the Photovoltaic (PV) voltage varies nonlinearily with temperature and isolation level, but is directly proportional to the PV cell open circuit voltage. The proportionality voltage-factor is fixed for a given PV generator regardless of temperature, isolation and panel configuration, but depends on cell material and manufacturing. This remarkable property is used to achieve

346

Power anomaly effects and costs in low-voltage mobile power systems  

Microsoft Academic Search

Electric power anomalies or disturbances can disrupt the normal operation of equipment, accelerate aging, or even cause outright failures thus resulting in increased costs of maintenance and reduced system reliability. Past research on the effects caused by power anomalies has been mostly focused on industrial, commercial, or residential systems, or on power distribution equipment. A literature survey reveals that there

Shengyi Liu; Charles H. Singer; Roger A. Dougal

2006-01-01

347

Observation of pressure stimulated voltages in rocks using an electric potential sensor  

SciTech Connect

Recent interest in the electrical activity in rock and the use of electric field transients as candidates for earthquake precursors has led to studies of pressure stimulated currents in laboratory samples. In this paper, an electric field sensor is used to measure directly the voltages associated with these currents. Stress was applied as uniaxial compression to marble and granite at an approximately constant rate. In contrast with the small pressure stimulated currents previously measured, large voltage signals are reported. Polarity reversal of the signal was observed immediately before fracture for the marble, in agreement with previous pressure stimulated current studies.

Aydin, A.; Prance, R. J.; Prance, H.; Harland, C. J. [Centre for Physical Electronics and Quantum Technology, School of Engineering and Design, University of Sussex, Brighton BN1 9QT (United Kingdom)

2009-09-21

348

Methods for Estimation of Market Power in Electric Power Industry  

NASA Astrophysics Data System (ADS)

The article is related to a topical issue of the newly-arisen market power phenomenon in the electric power industry. The authors point out to the importance of effective instruments and methods for credible estimation of the market power on liberalized electricity market as well as the forms and consequences of market power abuse. The fundamental principles and methods of the market power estimation are given along with the most common relevant indicators. Furthermore, in the work a proposal for determination of the relevant market place taking into account the specific features of power system and a theoretical example of estimating the residual supply index (RSI) in the electricity market are given.

Turcik, M.; Oleinikova, I.; Junghans, G.; Kolcun, M.

2012-01-01

349

Electric vehicle system for charging and supplying electrical power  

DOEpatents

A power system that provides power between an energy storage device, an external charging-source/load, an onboard electrical power generator, and a vehicle drive shaft. The power system has at least one energy storage device electrically connected across a dc bus, at least one filter capacitor leg having at least one filter capacitor electrically connected across the dc bus, at least one power inverter/converter electrically connected across the dc bus, and at least one multiphase motor/generator having stator windings electrically connected at one end to form a neutral point and electrically connected on the other end to one of the power inverter/converters. A charging-sourcing selection socket is electrically connected to the neutral points and the external charging-source/load. At least one electronics controller is electrically connected to the charging-sourcing selection socket and at least one power inverter/converter. The switch legs in each of the inverter/converters selected by the charging-source/load socket collectively function as a single switch leg. The motor/generators function as an inductor.

Su, Gui Jia

2010-06-08

350

Concerns generated by islanding [electric power generation  

Microsoft Academic Search

The purpose of this article is to discuss islanding operation and to provide end-users with items to consider when determining distributed generation plant and equipment design requirements. Islanding is operating an electric generating plant without an external voltage and frequency reference. Operating in parallel is the opposite of islanding. This article attempts to describe the valid concerns that grid operators

P. L. Villenueve

2004-01-01

351

The Effect of High Voltage, High Frequency Pulsed Electric Field on Slain Ovine Cortical Bone  

PubMed Central

High power, high frequency pulsed electric fields known as pulsed power (PP) has been applied recently in biology and medicine. However, little attention has been paid to investigate the application of pulse power in musculoskeletal system and its possible effect on functional behavior and biomechanical properties of bone tissue. This paper presents the first research investigating whether or not PP can be applied safely on bone tissue as a stimuli and what will be the possible effect of these signals on the characteristics of cortical bone by comparing the mechanical properties of this type of bone pre and post expose to PP and in comparison with the control samples. A positive buck-boost converter was applied to generate adjustable high voltage, high frequency pulses (up to 500 V and 10 kHz). The functional behavior of bone in response to pulse power excitation was elucidated by applying compressive loading until failure. The stiffness, failure stress (strength) and the total fracture energy (bone toughness) were determined as a measure of the main bone characteristics. Furthermore, an ultrasonic technique was applied to determine and comprise bone elasticity before and after pulse power stimulation. The elastic property of cortical bone samples appeared to remain unchanged following exposure to pulse power excitation for all three orthogonal directions obtained from ultrasonic technique and similarly from the compression test. Nevertheless, the compressive strength and toughness of bone samples were increased when they were exposed to 66 h of high power pulsed electromagnetic field compared to the control samples. As the toughness and the strength of the cortical bone tissue are directly associated with the quality and integrity of the collagen matrix whereas its stiffness is primarily related to bone mineral content these overall results may address that although, the pulse power stimulation can influence the arrangement or the quality of the collagen network causing the bone strength and toughness augmentation, it apparently did not affect the mineral phase of the cortical bone material. The results also confirmed that the indirect application of high power pulsed electric field at 500 V and 10 kHz through capacitive coupling method was safe and did not destroy the bone tissue construction. PMID:24761375

Asgarifar, Hajarossadat; Oloyede, Adekunle; Zare, Firuz

2014-01-01

352

Modular Solar Electric Power (MSEP) Systems (Presentation)  

Microsoft Academic Search

This presentation discusses the development and deployment of Modular Solar Electric Power (MSEP) systems, the feasibility of application of existing binary power cycles to solar trough technology, and identification of next action items.

Hassani

2000-01-01

353

Conic optimization of electric power systems  

E-print Network

The electric power grid is recognized as an essential modern infrastructure that poses numerous canonical design and operational problems. Perhaps most critically, the inherently large scale of the power grid and similar ...

Taylor, Joshua Adam

2011-01-01

354

Low-voltage ultra-low-poweranalog IC design -djmamic translinearcircuits 1.3.1 1.3 Low-voltage ultra-low-power analog IC design  

E-print Network

Low-voltage ultra-low-poweranalog IC design -djmamic translinearcircuits 1.3.1 1.3 Low-voltage ultra-low-power analog IC design -dynamic translinear circuits 0 (rg G x m .- E . . . . . a r, a" P, 44' s" +N m - _ c o3 #12;Low-voltage ultra-low-power analog IC design -dynamic translinear circuits I

Serdijn, Wouter A.

355

Electric power monthly, September 1990. [Glossary included  

SciTech Connect

The purpose of this report is to provide energy decision makers with accurate and timely information that may be used in forming various perspectives on electric issues. The power plants considered include coal, petroleum, natural gas, hydroelectric, and nuclear power plants. Data are presented for power generation, fuel consumption, fuel receipts and cost, sales of electricity, and unusual occurrences at power plants. Data are compared at the national, Census division, and state levels. 4 figs., 52 tabs. (CK)

Not Available

1990-12-17

356

Exposure of workers in the electric power industry to electric and magnetic fields.  

PubMed

A survey of 50 Hz electric and magnetic fields in the electric power industry has distinguished differences in exposure among the employees making it possible to compare health effects as a function of exposure. The workers that were most exposed to electric and magnetic fields were linemen and substation personnel who worked on facilities at operating voltages above 20 kV. On average, they were exposed to an electric field strength above 30 V/m for approximately 1.5 to 3 hours per day and to a magnetic flux density of around 1 to 2 microT. The least exposed group were linemen working in the 0.4 to 20 kV part of the network with exposure to a magnetic field of 0.10 microT. The electric field seldom exceeded 30 V/m. PMID:8047670

Lindh, T; Andersson, L I

1994-01-01

357

46 CFR 183.324 - Dual voltage generators.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Dual voltage generators. 183.324 Section 183... ELECTRICAL INSTALLATION Power Sources and Distribution Systems...183.324 Dual voltage generators. (a) A dual voltage generator installed on a vessel...

2010-10-01

358

46 CFR 129.326 - Dual-voltage generators.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 false Dual-voltage generators. 129.326 Section 129...ELECTRICAL INSTALLATIONS Power Sources and Distribution Systems...129.326 Dual-voltage generators. If a dual-voltage generator is installed on an...

2011-10-01

359

46 CFR 129.326 - Dual-voltage generators.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 false Dual-voltage generators. 129.326 Section 129...ELECTRICAL INSTALLATIONS Power Sources and Distribution Systems...129.326 Dual-voltage generators. If a dual-voltage generator is installed on an...

2013-10-01

360

46 CFR 129.326 - Dual-voltage generators.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 false Dual-voltage generators. 129.326 Section 129...ELECTRICAL INSTALLATIONS Power Sources and Distribution Systems...129.326 Dual-voltage generators. If a dual-voltage generator is installed on an...

2012-10-01

361

46 CFR 120.324 - Dual voltage generators.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 false Dual voltage generators. 120.324 Section 120... ELECTRICAL INSTALLATION Power Sources and Distribution Systems...120.324 Dual voltage generators. (a) A dual voltage generator installed on a vessel...

2011-10-01

362

46 CFR 183.324 - Dual voltage generators.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 false Dual voltage generators. 183.324 Section 183... ELECTRICAL INSTALLATION Power Sources and Distribution Systems...183.324 Dual voltage generators. (a) A dual voltage generator installed on a vessel...

2011-10-01

363

46 CFR 120.324 - Dual voltage generators.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 false Dual voltage generators. 120.324 Section 120... ELECTRICAL INSTALLATION Power Sources and Distribution Systems...120.324 Dual voltage generators. (a) A dual voltage generator installed on a vessel...

2013-10-01

364

46 CFR 120.324 - Dual voltage generators.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 false Dual voltage generators. 120.324 Section 120... ELECTRICAL INSTALLATION Power Sources and Distribution Systems...120.324 Dual voltage generators. (a) A dual voltage generator installed on a vessel...

2012-10-01

365

46 CFR 183.324 - Dual voltage generators.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 false Dual voltage generators. 183.324 Section 183... ELECTRICAL INSTALLATION Power Sources and Distribution Systems...183.324 Dual voltage generators. (a) A dual voltage generator installed on a vessel...

2013-10-01

366

46 CFR 129.326 - Dual-voltage generators.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 false Dual-voltage generators. 129.326 Section 129...ELECTRICAL INSTALLATIONS Power Sources and Distribution Systems...129.326 Dual-voltage generators. If a dual-voltage generator is installed on an...

2014-10-01

367

46 CFR 183.324 - Dual voltage generators.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 false Dual voltage generators. 183.324 Section 183... ELECTRICAL INSTALLATION Power Sources and Distribution Systems...183.324 Dual voltage generators. (a) A dual voltage generator installed on a vessel...

2012-10-01

368

46 CFR 120.324 - Dual voltage generators.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 false Dual voltage generators. 120.324 Section 120... ELECTRICAL INSTALLATION Power Sources and Distribution Systems...120.324 Dual voltage generators. (a) A dual voltage generator installed on a vessel...

2014-10-01

369

46 CFR 120.324 - Dual voltage generators.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Dual voltage generators. 120.324 Section 120... ELECTRICAL INSTALLATION Power Sources and Distribution Systems...120.324 Dual voltage generators. (a) A dual voltage generator installed on a vessel...

2010-10-01

370

46 CFR 183.324 - Dual voltage generators.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 false Dual voltage generators. 183.324 Section 183... ELECTRICAL INSTALLATION Power Sources and Distribution Systems...183.324 Dual voltage generators. (a) A dual voltage generator installed on a vessel...

2014-10-01

371

46 CFR 129.326 - Dual-voltage generators.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Dual-voltage generators. 129.326 Section 129...ELECTRICAL INSTALLATIONS Power Sources and Distribution Systems...129.326 Dual-voltage generators. If a dual-voltage generator is installed on an...

2010-10-01

372

Effects of power line voltage variations on different types of 400-W high-pressure sodium ballasts  

SciTech Connect

This paper presents the results of laboratory tests to determine the effects of voltage sags, interruptions, and fluctuations on high-pressure sodium (HPS) lamps and ballasts. The way these ballasted lamps react to sags and interruptions in the laboratory is then compared to a model of the real-world electrical environment created from data gathered during three recent North American power quality surveys. This work also shows how HPS immunity to voltage variations depends significantly on the ballast type and the lamp age.

Dorr, D.S.; Mansoor, A. [EPRI Power Electronics Applications Center, Knoxville, TN (United States)] [EPRI Power Electronics Applications Center, Knoxville, TN (United States); Morinec, A.G. [Centerior Energy Corp., Cleveland, OH (United States)] [Centerior Energy Corp., Cleveland, OH (United States); Worley, J.C. [East Kentucky Power Cooperative, Winchester, KY (United States)] [East Kentucky Power Cooperative, Winchester, KY (United States)

1997-03-01

373

Three essays on "making" electric power markets  

NASA Astrophysics Data System (ADS)

Technological change over the past three decades has altered most of the basic conditions in the electric power industry. Because of technical progress, the dominant paradigm has shifted from the provision of electric power by regulated and vertically integrated local natural monopolies to competition and vertical separation. In the first essay I provide a historical context of the electric industry's power current deregulation debate. Then a dynamic model of induced institutional change is used to investigate how endogenous technological advancements have induced radical institutional change in the generation and transmission segments of the electric power industry. Because the Federal Energy Regulatory Commission (FERC) ordered regulated utilities to provide open access to their transmission networks and to separate their generation and transmission functions, transmission networks have been used more intensively and in much different ways then in the past. The second essay tests experimentally the predictions of neoclassical theory for a radial electric power market under two alternative deregulated transmission institutions: financial transmission rights and physical transmission rights. Experimental evidence presented there demonstrates that an electric power market with physical transmission rights governing its transmission network generates more "right" market signals relative to a transmission network governed by financial transmission rights. The move to a greater reliance on markets for electric power is an idea that has animated sweeping and dramatic changes in the traditional business of electric power. The third essay examines two of the most innovative and complex initiatives of making electric power markets in the United States: California and PJM. As those markets mature and others are made, they must revise their governance mechanisms to eliminate rules that create inefficiency and adopt rules that work efficiently elsewhere. I argue that restructured electric power markets in the United States we should consider adopting an integrated procurement approach for electric power and ancillary services, binding forward markets for those commodities, and a market for physical transmission rights.

Kench, Brian Thomas

2000-10-01

374

46 CFR 28.850 - Main source of electrical power.  

Code of Federal Regulations, 2013 CFR

... Main source of electrical power. 28.850 Section 28... Main source of electrical power. (a) Applicability...that relies on electricity to power any of the following essential...have at least two electrical generators to supply: (1) The...

2013-10-01

375

46 CFR 28.850 - Main source of electrical power.  

Code of Federal Regulations, 2014 CFR

... Main source of electrical power. 28.850 Section 28... Main source of electrical power. (a) Applicability...that relies on electricity to power any of the following essential...have at least two electrical generators to supply: (1) The...

2014-10-01

376

46 CFR 28.355 - Main source of electrical power.  

Code of Federal Regulations, 2013 CFR

... Main source of electrical power. 28.355 Section 28... Main source of electrical power. (a) Applicability...that relies on electricity to power any of the following essential...have at least two electrical generators to supply these loads:...

2013-10-01

377

46 CFR 28.355 - Main source of electrical power.  

Code of Federal Regulations, 2012 CFR

... Main source of electrical power. 28.355 Section 28... Main source of electrical power. (a) Applicability...that relies on electricity to power any of the following essential...have at least two electrical generators to supply these loads:...

2012-10-01

378

46 CFR 28.355 - Main source of electrical power.  

Code of Federal Regulations, 2014 CFR

... Main source of electrical power. 28.355 Section 28... Main source of electrical power. (a) Applicability...that relies on electricity to power any of the following essential...have at least two electrical generators to supply these loads:...

2014-10-01

379

46 CFR 28.850 - Main source of electrical power.  

Code of Federal Regulations, 2012 CFR

... Main source of electrical power. 28.850 Section 28... Main source of electrical power. (a) Applicability...that relies on electricity to power any of the following essential...have at least two electrical generators to supply: (1) The...

2012-10-01

380

46 CFR 28.355 - Main source of electrical power.  

Code of Federal Regulations, 2011 CFR

... Main source of electrical power. 28.355 Section 28... Main source of electrical power. (a) Applicability...that relies on electricity to power any of the following essential...have at least two electrical generators to supply these loads:...

2011-10-01

381

46 CFR 28.850 - Main source of electrical power.  

Code of Federal Regulations, 2011 CFR

... Main source of electrical power. 28.850 Section 28... Main source of electrical power. (a) Applicability...that relies on electricity to power any of the following essential...have at least two electrical generators to supply: (1) The...

2011-10-01

382

DOI:01.IJEPE.02.03. ACEEE Int. J. on Electrical and Power Engineering, Vol. 02, No. 03, Nov2011  

E-print Network

-voltage environment such as in portable and battery- powered equipments. Since a low-voltage operating circuit becomes©2011ACEEE DOI:01.IJEPE.02.03. ACEEE Int. J. on Electrical and Power Engineering, Vol. 02, No. 03, the proposed circuit is then suitable for IC architecture. The PSpice simulation and experimental results

Paris-Sud XI, Université de

383

Voltage-current characteristics of a high-power pulsed sputtering (HPPS) glow discharge and plasma density estimation  

NASA Astrophysics Data System (ADS)

A droplet-free metallic plasma source is promising for enhanced adhesion of films with a smooth coating surface. This paper concerns the study of a highly ionized metallic plasma source using a pulsed Penning discharge designed with a magnetic field oriented parallel to an electric field. Such a plasma is called a high-power pulsed sputtering (HPPS) glow discharge plasma. This technology is related to so-called high-power impulse magnetron sputtering (HIPIMS), though the interaction of the magnetic and electric field in the HPPS glow plasma is different from the HIPIMS plasma. The titanium metallic species are sputtered by energetic argon ion bombardment, causing their ionization in as short as a few microsecond. The typical electrical characteristics are as follows: a peak current of 45 A (0.9 A/cm 2), a peak power of 18 kW (0.8 kW/cm 2), and an average power of 1 kW. The target voltage is approximately 400 V at 30 ?s for glow currents of 30-120 A. A negative pulse voltage is applied to the substrate holder electrode to extract ions from the magnetically confined HPPS glow plasma. Using the recovery characteristics of the voltage applied to the substrate, the ion density at the substrate surface is estimated to be on the order of 10 16-17 m -3 for a singly charged titanium plasma.

Yukimura, Ken; Mieda, Ryosuke; Azuma, Kingo; Tamagaki, Hiroshi; Okimoto, Tadao

2009-05-01

384

Determination of the cathode and anode voltage drops in high power low-pressure amalgam lamps  

SciTech Connect

For the first time, cathode and anode drops of powerful low-pressure amalgam lamps were measured. The lamp discharge current is 3.2 A, discharge current frequency is 43 kHz, linear electric power is 2.4 W/cm. The method of determination of a cathode drop is based on the change of a lamp operating voltage at variation of the electrode filament current at constant discharge current. The total (cathode plus anode) drop of voltage was measured by other, independent ways. The maximum cathode fall is 10.8 V; the anode fall corresponding to the maximal cathode fall is 2.4 V. It is shown that in powerful low pressure amalgam lamps the anode fall makes a considerable contribution (in certain cases, the basic one) to heating of electrodes. Therefore, the anode fall cannot be neglected, at design an electrode and ballast of amalgam lamps with operating discharge current frequency of tens of kHz.

Vasilyak, L. M., E-mail: vasilyak@ihed.ras.ru [Russian Academy of Sciences, Joint Institute for High Temperatures (Russian Federation); Vasiliev, A. I., E-mail: vasiliev@npo.lit.ru; Kostyuchenko, S. V.; Sokolov, D. V.; Startsev, A. Yu. [Joint Stock Company NPO LIT (Russian Federation); Kudryavtsev, N. N. [Moscow Institute of Physics and Technology (State University) (Russian Federation)

2011-12-15

385

Study on Optimization Strategy for Voltage and Reactive Power Control of Wind Farm  

NASA Astrophysics Data System (ADS)

A method for calculating reactive power limit of wind farm comprised of doubly-fed induction generators (DFIG) is proposed. The reactive power limit of wind farm is the sum of reactive power limit of DFIGs which is calculated by the method considering static stability margin. Based on this, reactive power control of wind farm is discussed and proposed. The proposed reactive power control is divided into different control modes according to power factor of high voltage side in wind farm substation and voltage of low voltage side in point of interconnection(POI). In different control modes, different control objects are applied on reactive power regulation. After reactive power regulation is finished, some reactive power of wind farm should be released. At last, numerical test system is established, the result shows that the proposed method is effective to support voltage of POI

Lu, Q.; Shi, L.; Chen, N.

386

Electric Power Delivery Testing Feasibility Study Task 6 Final Report  

SciTech Connect

This Final Report is covers the completion of the Electric Power Delivery Testing Feasibility Study. The objective of this project was to research, engineer, and demonstrate high-power laboratory testing protocols to accurately reproduce the conditions on the electric power grid representing both normal load switching and abnormalities such as short-circuit fault protection. Test circuits, equipment, and techniques were developed and proven at reduced power levels to determine the feasibility of building a large-scale high-power testing laboratory capable of testing equipment and systems at simulated high-power conditions of the U.S. power grid at distribution levels up through 38 kiloVolts (kV) and transmission levels up through 230 kV. The project delivered demonstrated testing techniques, high-voltage test equipment for load testing and synthetic short-circuit testing, and recommended designs for future implementation of a high-power testing laboratory to test equipment and systems, enabling increased reliability of the electric transmission and distribution grid.

Thomas Tobin

2009-07-01

387

Measurements of transient electrical noise on low voltage distribution systems  

Microsoft Academic Search

Electrical noise measurements which were undertaken in preparation of designing a low-frequency (below 100 kHz) carrier current system for use in protective relaying are discussed. Steady-state measurements were made to assess the fluctuating noise level on a 600 V bus over a 24 hour period, and transient measurements were taken to discover the extent of the electrical noise generated in

PETER T. ASHTON; GLENN W. SWIFT

1990-01-01

388

Voltage-noise-induced transitions in electrically excitable membranes.  

PubMed Central

A quantitative study of the steady-state behavior of the sodium and potassium conductance for the Hodgkin-Huxley axon under the influence of an externally driven voltage noise is reported. The dichotomous Markov noise (random telegraph signal) considered allows for an exact evaluation of the stationary probability density of the conductances. Phase diagrams are constructed to represent the response of the system as a function of the amplitude and the correlation time of the noise. The results obtained for the Hodgkin-Huxley axon are compared with some molecular models used in the literature. PMID:7272445

Horsthemke, W; Lefever, R

1981-01-01

389

Modeling the motion of a toy train powered with a time-dependent applied voltage: Educational implementation and analysis  

NASA Astrophysics Data System (ADS)

We describe the motion of an electric toy train engine that is powered by a time-dependent voltage and travels on a horizontal track. Effects such as friction, the electrically induced torque and electromotive force of the motor, resistance, inductance, and applied voltage are investigated to identify the impact of each on the train's performance. The parameters that describe these effects are experimentally extracted by considering the train's steady-state motion achieved for a constant applied voltage. An equivalent inertia parameter is obtained from transient velocity and current measurements. These parameters are employed in a numerical solution to predict the train's velocity and current for a time-dependent applied voltage. The results are compared with measured values for several independent cases. This analysis has been successfully incorporated into an advanced group project for an introductory course in electricity and magnetism and can be adapted to accommodate students at different levels. Its implementation as an alternative to the traditional laboratory experience is discussed and an assessment of its effectiveness is presented based on the Conceptual Survey in Electricity and Magnetism.

Wick, D. P.; Ramsdell, M. W.

2004-07-01

390

A novel strategy for selection of the optimal number and location of UPFC devices in deregulated electric power systems  

Microsoft Academic Search

The increases in power flows and environmental constraints are forcing electricity utilities to install new equipment to enhance network operation. Some application of flexible AC transmission system (FACTS) technologies to existing high-voltage power systems has proved the use of FACTS technology may be a cost-effective option for power delivery system enhancements. Amongst various power electronic devices, the unified power flow

L. Ippolito

2005-01-01

391

Advanced electrical power system technology for the all electric aircraft  

NASA Technical Reports Server (NTRS)

The application of advanced electric power system technology to an all electric airplane results in an estimated reduction of the total takeoff gross weight of over 23,000 pounds for a large airplane. This will result in a 5 to 10 percent reduction in direct operating costs (DOC). Critical to this savings is the basic electrical power system component technology. These advanced electrical power components will provide a solid foundation for the materials, devices, circuits, and subsystems needed to satisfy the unique requirements of advanced all electric aircraft power systems. The program for the development of advanced electrical power component technology is described. The program is divided into five generic areas: semiconductor devices (transistors, thyristors, and diodes); conductors (materials and transmission lines); dielectrics; magnetic devices; and load management devices. Examples of progress in each of the five areas are discussed. Bipolar power transistors up to 1000 V at 100 A with a gain of 10 and a 0.5 microsec rise and fall time are presented. A class of semiconductor devices with a possibility of switching up to 100 kV is described. Solid state power controllers for load management at 120 to 1000 V and power levels to 25 kW were developed along with a 25 kW, 20 kHz transformer weighing only 3.2 kg.

Finke, R. C.; Sundberg, G. R.

1983-01-01

392

Reactive Power Support Services in Electricity Markets  

E-print Network

support services. These services include the resources available to generators as well as transmissionReactive Power Support Services in Electricity Markets Costing and Pricing of Ancillary Services Reactive Power Support Services in Electricity Markets Costing and Pricing of Ancillary Services Project

393

Electric Power Monthly, August 1990. [Glossary included  

SciTech Connect

The Electric Power Monthly (EPM) presents monthly summaries of electric utility statistics at the national, Census division, and State level. The purpose of this publication is to provide energy decisionmakers with accurate and timely information that may be used in forming various perspectives on electric issues that lie ahead. Data includes generation by energy source (coal, oil, gas, hydroelectric, and nuclear); generation by region; consumption of fossil fuels for power generation; sales of electric power, cost data; and unusual occurrences. A glossary is included.

Not Available

1990-11-29

394

Developments in voltage regulation of variable-speed PM synchronous alternators in automotive electric systems  

Microsoft Academic Search

ó This paper evaluates the performance of a voltage regulator for a high-efciency , high-energy density alternator system that comprises of a PM syn- chronous generator and a swithced-mode rectier . A closed-loop control system is designed to regulate the out- put dc voltage of the alternator system operated under varying engine speeds, electrical loads, and battery state- of-charge conditions.

Levent Ovacik; Berker Bilgin

2011-01-01

395

PHYSICAL REVIEW B 83, 134408 (2011) Size-dependent electric voltage controlled magnetic anisotropy in multiferroic heterostructures  

E-print Network

PHYSICAL REVIEW B 83, 134408 (2011) Size-dependent electric voltage controlled magnetic anisotropy) We present a phenomenological scheme to study the size-dependent electric voltage-controlled magnetic between the magnetic and electric polarizations.1­3 Of particular interest in the multiferroic

Chen, Long-Qing

2011-01-01

396

35. SITE BUILDING 004 ELECTRIC POWER STATION CONTROL ...  

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

35. SITE BUILDING 004 - ELECTRIC POWER STATION - CONTROL ROOM OF ELECTRIC POWER STATION WITH DIESEL ENGINE POWERED ELECTRIC GENERATION EQUIPMENT IN BACKGROUND. - Cape Cod Air Station, Technical Facility-Scanner Building & Power Plant, Massachusetts Military Reservation, Sandwich, Barnstable County, MA

397

75 FR 23823 - Sixth Northwest Electric Power and Conservation Plan  

Federal Register 2010, 2011, 2012, 2013, 2014

...power plan, the Northwest Electric Power and Conservation Plan...comment the Draft Northwest Sixth Electric Power and Conservation Plan...called the Sixth Northwest Electric Power and Conservation Plan...Council's Columbia River Basin Fish and Wildlife Program,...

2010-05-04

398

Exposure assessment for power frequency electric and magnetic fields.  

PubMed

Over the past decade considerable data have been collected on electric and magnetic fields in occupational environments. These data have taken the form of area measurements, source characterizations, and personal exposure measurements. Occupational EMF levels are highly variable in space and time. Exposures associated with these fields exhibit similar large variations during a day, between days, and between individuals within a group. The distribution of exposure measures is skewed over several decades with only a few values occurring at the maximum field levels. The skewness of exposure measures implies that large sample sizes may be required for assessments and that multiple statistical descriptors are preferred to describe individual and group exposures. Except for the relatively few occupational settings where high voltage sources are prevalent, electric fields encountered in the workplace are probably similar to residential exposures. Consequently, high electric field exposures are essentially limited to utility environments and occupations. Within the electric utility industry, it is definitely possible to identify occupations with high electric field exposures relative to those of office workers or other groups. The highly exposed utility occupations are linemen, substation operators, and utility electricians. The distribution of electric field exposures in the utility worker population is very skewed even within a given occupation. As with electric fields, magnetic fields in the workplace appear to be comparable with residential levels, unless a clearly defined high-current source is present. Since high-current sources are more prevalent than high-voltage sources, environments with relatively high magnetic field exposures encompass a more diverse set of occupations than do those with high electric fields. Within the electric utility industry, it is possible to identify occupational environments with high magnetic field exposure relative to the office environment. Utility job categories with the highest exposures are generation facility workers, substation operators, utility linemen, and utility electricians. There are also higher exposures among traditional "electrical worker" job categories. Outside the electrical utility industry, potential sources of high occupational magnetic field exposures at ELF are induction furnaces, welding machines, electrical transportation systems, and electrical distribution vaults. However, the use of low power electrical equipment such as small motors in close proximity to workers and possibly for long periods of time could also lead to high exposure situations. Handheld survey instruments are available to perform area measurements of electric and magnetic fields at power frequencies but not aat all frequencies within the ELF range. Sophisticated personal computer-based instruments are available to characterize areas and sources across the entire frequency range.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:8480632

Bracken, T D

1993-04-01

399

Power Supply Rejection Improvement Techniques In Low Drop-Out Voltage Regulators  

E-print Network

Low drop out (LDO) voltage regulators are widely used for post regulating the switching ripples generated by the switched mode power supplies (SMPS). Due to demand for portable applications, industry is pushing for complete system on chip power...

Ganta, Saikrishna

2011-10-21

400

Design of a low-voltage low-power dc-dc HF converter  

E-print Network

Many portable electronic applications could benefit from a power converter able to achieve high efficiency across wide input and output voltage ranges at a small size. However, it is difficult for many conventional power ...

Hu, Jingying, Ph. D. Massachusetts Institute of Technology.

2008-01-01

401

Electric power monthly, March 1995  

SciTech Connect

This report for March 1995, presents monthly electricity statistics for a wide audience including Congress, Federal and State agencies, the electric utility industry, and the general public. The purpose of this publication is to provide energy decisionmakers with accurate and timely information that may be used in forming various perspectives on electric issues that lie ahead.

NONE

1995-03-20

402

Influence of electrical stress voltage on cathode degradation of organic light-emitting devices  

NASA Astrophysics Data System (ADS)

Our in situ experimental observations of the influence of electrical stress voltage on organic light-emitting device growth in dark spot areas are presented. We demonstrate the use of microsized silica particles to create uniformly sized defects on the protective layer. This is an efficient way to control the location and the number of dark spots. The growth in dark spot area was studied at different driving voltages from 0 up to 11 V. Dark field microscopy was used to monitor the dark spot size below the turn-on voltage. The bright field was used at or above the turn-on voltage. Our observations indicate that dark spot growth was strongly affected by the electrical stress voltage. A linear growth rate with respect to the voltage was observed with a fitting parameter better than 99.7% when the device is driven above the turn-on voltage. We interpret the dark spot growth in terms of the diffusion of moisture and oxygen accompanied by cathode layer chemical and physical changes.

Lin, Karen Ke; Chua, Soo Jin; Wei-Wang, Lim, Shuang Fang

2001-07-01

403

A new current control strategy for active power filters using three PWM voltage source inverters  

Microsoft Academic Search

A new current control strategy for active power filters using multiple PWM voltage-source inverters is presented and analyzed. The proposed current control strategy operates each PWM voltage-source inverter with a different switching frequency generating specific current harmonic components of the load. Reactive power is compensated without sensing and computing the reactive component of the load current, thus simplifying the control

Luis Moran; Pedro Godoy; Rogel Wallace; Juan Dixon

1993-01-01

404

30 CFR 75.812-2 - High-voltage power centers and transformers; record of examination.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false High-voltage power centers and transformers; record of examination. 75.812-2 Section 75.812-2...Distribution § 75.812-2 High-voltage power centers and transformers; record of examination. The operator shall...

2010-07-01

405

A Two-Stage Distributed Architecture for Voltage Control in Power Distribution Systems  

E-print Network

can collectively provide the reactive power estimated by the local controller, they are instructed, the additional power demand introduced by massive charging of PHEVs can potentially cause unacceptable voltage drops [8]. Voltage violations are traditionally handled by automatically- controlled tap-changing under

Hadjicostis, Christoforos

406

30 CFR 75.812-2 - High-voltage power centers and transformers; record of examination.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false High-voltage power centers and transformers; record of examination. 75.812-2 Section 75.812-2...Distribution § 75.812-2 High-voltage power centers and transformers; record of examination. The operator shall...

2013-07-01

407

30 CFR 75.812-2 - High-voltage power centers and transformers; record of examination.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false High-voltage power centers and transformers; record of examination. 75.812-2 Section 75.812-2...Distribution § 75.812-2 High-voltage power centers and transformers; record of examination. The operator shall...

2012-07-01

408

30 CFR 75.812-2 - High-voltage power centers and transformers; record of examination.  

Code of Federal Regulations, 2014 CFR

...2014-07-01 false High-voltage power centers and transformers; record of examination. 75.812-2 Section 75.812-2...Distribution § 75.812-2 High-voltage power centers and transformers; record of examination. The operator shall...

2014-07-01

409

30 CFR 75.812-2 - High-voltage power centers and transformers; record of examination.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false High-voltage power centers and transformers; record of examination. 75.812-2 Section 75.812-2...Distribution § 75.812-2 High-voltage power centers and transformers; record of examination. The operator shall...

2011-07-01

410

Fuzzy dynamic programming approach to reactive power\\/voltage control in a distribution substation  

Microsoft Academic Search

A fuzzy dynamic programming (FDP) approach is proposed for solving the reactive power\\/voltage control problem in a distribution substation. The main purpose is to improve the voltage profile on the secondary bus and restrain the reactive power flow into a main transformer at the same time. To reach our objectives, the load tap changer (LTC) usually installed in a main

Feng-Chang Lu; Yuan-Yih Hsu

1997-01-01

411

Design methodology of ultra low-power MPEG4 codec core exploiting voltage scaling techniques  

Microsoft Academic Search

This paper describes a fully automated low-power design methodology in which three different voltage-scaling techniques are combined together. Supply voltage is scaled globally, selectively, and adaptively while keeping the performance. This methodology enabled us to design an MPEG4 codec core with 58% less power than the original in three week turn-around-time.

Kimiyoshi Usami; Mutsunori Igarashi; Takashi Ishikawa; Masahiro Kanazawa; Masafumi Takahashi; Mototsugu Hamada; Hideho Arakida; Toshihiro Terazawa; Tadahiro Kuroda

1998-01-01

412

An integrated approach for the voltage stability enhancement of large wind integrated power systems  

Microsoft Academic Search

This paper investigates the applicability of an integrated approach for the enhancement of voltage stability margin and there by the wind penetration of large wind integrated power systems. The proposed approach involves in two objectives; the identification of weak buses in the given power systems, enhancement of voltage stability margin of the weak buses and there by the wind penetration

B Maya; Sasidharan Sreedharan; Jai Govind Singh

2012-01-01

413

Trees and Power Lines: Minimizing Conflicts between Electric Power  

E-print Network

Trees and Power Lines: Minimizing Conflicts between Electric Power Infrastructure and the Urban Forest By William Brock Most 1 and Steven Weissman 2 March 10, 2012 #12;iiTrees and Power Lines Trees and Power Lines 5 5. Benefits of the Urban Forest 6 a. Carbon Sequestration 6 b. Property Value 6

Kammen, Daniel M.

414

High voltage lateral power transisters: Theory and design  

NASA Astrophysics Data System (ADS)

A new lateral device, the lateral bipolar field effect transistor or LABFET, is described. This device replaces the normal n+-drain diffusion, used in the typical double diffused MOS(DMOS) transistor with a p-type diffusion. This p-diffusion acts as the emitter of a low gain p-n-p bipolar transistor. The base of this device is the n-substrate or n-well, when the device is part of an integrated circuit. The base current is supplied by turning on the DMOS field effect transistor. The result is a conductivity modulated device, with all terminals on the top of the chip, a voltage withstand capability of 100 V and an on-state conductance of .71 Siemans per cm of gate width. This is comparable with conventional vertical FET devices. The static and dynamic characteristics of unit cell devices are presented with an explanation of the results and a description of the processing to produce them. Finally, suggestions are made which would allow the extension of this concept to a large device suitable for integration into a power integrated circuit.

Benjamin, J. A.

1984-06-01

415

Analysis and calculation of lightning-induced voltages in aircraft electrical circuits  

NASA Technical Reports Server (NTRS)

Techniques to calculate the transfer functions relating lightning-induced voltages in aircraft electrical circuits to aircraft physical characteristics and lightning current parameters are discussed. The analytical work was carried out concurrently with an experimental program of measurements of lightning-induced voltages in the electrical circuits of an F89-J aircraft. A computer program, ETCAL, developed earlier to calculate resistive and inductive transfer functions is refined to account for skin effect, providing results more valid over a wider range of lightning waveshapes than formerly possible. A computer program, WING, is derived to calculate the resistive and inductive transfer functions between a basic aircraft wing and a circuit conductor inside it. Good agreement is obtained between transfer inductances calculated by WING and those reduced from measured data by ETCAL. This computer program shows promise of expansion to permit eventual calculation of potential lightning-induced voltages in electrical circuits of complete aircraft in the design stage.

Plumer, J. A.

1974-01-01

416

SITE ELECTRICAL POWER SYSTEM DESCRIPTION DOCUMENT  

SciTech Connect

The Site Electrical Power System receives and distributes utility power to all North Portal site users. The major North Portal users are the Protected Area including the subsurface facility and Balance of Plant areas. The system is remotely monitored and controlled from the Surface Operations Monitoring and Control System. The system monitors power quality and provides the capability to transfer between Off-Site Utility and standby power (including dedicated safeguards and security power). Standby power is only distributed to selected loads for personnel safety and essential operations. Security power is only distributed to essential security operations. The standby safeguards and security power is independent from all other site power. The system also provides surface lighting, grounding grid, and lightning protection for the North Portal. The system distributes power during construction, operation, caretaker, and closure phases of the repository. The system consists of substation equipment (disconnect switches, breakers, transformers and grounding equipment) and power distribution cabling from substation to the north portal switch gear building. Additionally, the system includes subsurface facility substation (located on surface), switch-gear, standby diesel generators, underground duct banks, power cables and conduits, switch-gear building and associated distribution equipment for power distribution. Each area substation distributes power to the electrical loads and includes the site grounding, site lighting and lightning protection equipment. The site electrical power system distributes power of sufficient quantity and quality to meet users demands. The Site Electrical Power System interfaces with the North Portal surface systems requiring electrical power. The system interfaces with the Subsurface Electrical Distribution System which will supply power to the underground facilities from the North Portal. Power required for the South Portal and development side activities of the subsurface facility will be provided at the South Portal by the Subsurface Electrical Distribution System. The Site Electrical Power System interfaces with the Off-Site Utility System for the receipt of power. The System interfaces with the Surface Operations Monitoring and Control System for monitoring and control. The System interfaces with MGR Site Layout System for the physical location of equipment and power distribution.

E.P. McCann

1999-04-16

417

An active power filter implemented with a three-level NPC voltage-source inverter  

Microsoft Academic Search

This paper presents an active power filter implemented using a three-level neutral point-clamped voltage-source inverter. The active power filter can compensate current harmonics and reactive power in medium voltage distribution systems. The paper presents the principles of operation and design criteria for both the power and control circuits. Finally, the viability of the proposed scheme is shown with computer simulation

Victor Aburto; M. Schneider; L. Moran; Juan Dixon

1997-01-01

418

Low-power design technique for ASICs by partially reducing supply voltage  

Microsoft Academic Search

In this paper, we discuss power reduction by comparing two different design techniques targeting low-power ASICs: clustered voltage scaling (CVS) and gate resizing. The CVS is a technique to reduce supply voltage partially, allowing one to reduce power without performance degradation. As a result of application to real gate-array circuits, the CVS reduced power by 30-60% even at dominant wire

Kimiyoshi Usami; Takashi Ishikawa; Masahiro Kanazawa; Hiroko Kotani

1996-01-01

419

Characteristic Analysis of DC Electric Railway Systems with Superconducting Power Cables Connecting Power Substations  

NASA Astrophysics Data System (ADS)

The application of superconducting power cables to DC electric railway systems has been studied. It could leads to an effective use of regenerative brake, improved energy efficiency, effective load sharing among the substations, etc. In this study, an electric circuit model of a DC feeding system is built and numerical simulation is carried out using MATLAB-Simulink software. A modified electric circuit model with an AC power grid connection taken into account is also created to simulate the influence of the grid connection. The analyses have proved that a certain amount of energy can be conserved by introducing superconducting cables, and that electric load distribution and concentration among the substations depend on the substation output voltage distribution.

Ohsaki, H.; Matsushita, N.; Koseki, T.; Tomita, M.

2014-05-01

420

Electric power annual 1996. Volume 1  

SciTech Connect

The Electric Power Annual presents a summary of electric power industry statistics at national, regional, and State levels. The objective of the publication is to provide industry decisionmakers, government policy-makers, analysts, and the general public with data that may be used in understanding US electricity markets. The Electric Power Annual is prepared by the Coal and Electric Data and Renewables Division; Office of Coal, Nuclear, Electric and Alternate Fuels; Energy Information Administration (EIA); US Department of Energy. Volume 1--with a focus on US electric utilities--contains final 1996 data on net generation and fossil fuel consumption, stocks, receipts, and cost; preliminary 1996 data on generating unit capability, and retail sales of electricity, associated revenue, and the average revenue per kilowatthour of electricity sold. Additionally, information on net generation from renewable energy sources and on the associated generating capability is included in Volume 1 of the EPA. Data published in the Electric Power Annual Volume 1 are compiled from three statistical forms filed monthly and two forms filed annually by electric utilities. These forms are described in detail in the Technical Notes. 5 figs., 30 tabs.

NONE

1997-08-01

421

Power supply  

DOEpatents

A modular, low weight impedance dropping power supply with battery backup is disclosed that can be connected to a high voltage AC source and provide electrical power at a lower voltage. The design can be scaled over a wide range of input voltages and over a wide range of output voltages and delivered power.

Yakymyshyn, Christopher Paul (Seminole, FL); Hamilton, Pamela Jane (Seminole, FL); Brubaker, Michael Allen (Loveland, CO)

2007-12-04

422

Re-Dispatching Generation to Increase Power System Security Margin and Support Low Voltage Bus  

E-print Network

Re-Dispatching Generation to Increase Power System Security Margin and Support Low Voltage Bus as generation directions (patterns). Keywords: power generation dispatch, power system control, power system cause many stability problems. Between the power system generation pattern and the load pattern

423

Easily disassembled electrical connector for high voltage, high frequency connections  

DOEpatents

An easily accessible electrical connector capable of rapid assembly and disassembly wherein a wide metal conductor sheet may be evenly contacted over the entire width of the conductor sheet by opposing surfaces on the connector which provide an even clamping pressure against opposite surfaces of the metal conductor sheet using a single threaded actuating screw.

Milner, Joseph R. (Livermore, CA)

1994-01-01

424

Easily disassembled electrical connector for high voltage, high frequency connections  

DOEpatents

An easily accessible electrical connector capable of rapid assembly and disassembly is described wherein a wide metal conductor sheet may be evenly contacted over the entire width of the conductor sheet by opposing surfaces on the connector which provide an even clamping pressure against opposite surfaces of the metal conductor sheet using a single threaded actuating screw. 13 figures.

Milner, J.R.

1994-05-10

425

30 CFR 77.500 - Electric power circuits and electric equipment; deenergization.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Electric power circuits and electric equipment; deenergization. 77.500...UNDERGROUND COAL MINES Electrical Equipment-General § 77.500 Electric power circuits and electric equipment;...

2011-07-01

426

30 CFR 77.500 - Electric power circuits and electric equipment; deenergization.  

Code of Federal Regulations, 2014 CFR

...2014-07-01 2014-07-01 false Electric power circuits and electric equipment; deenergization. 77.500...UNDERGROUND COAL MINES Electrical Equipment-General § 77.500 Electric power circuits and electric equipment;...

2014-07-01

427

30 CFR 77.500 - Electric power circuits and electric equipment; deenergization.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Electric power circuits and electric equipment; deenergization. 77.500...UNDERGROUND COAL MINES Electrical Equipment-General § 77.500 Electric power circuits and electric equipment;...

2013-07-01

428

30 CFR 75.509 - Electric power circuit and electric equipment; deenergization.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Electric power circuit and electric equipment; deenergization. 75.509...STANDARDS-UNDERGROUND COAL MINES Electrical Equipment-General § 75.509 Electric power circuit and electric equipment;...

2011-07-01

429

30 CFR 75.509 - Electric power circuit and electric equipment; deenergization.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Electric power circuit and electric equipment; deenergization. 75.509...STANDARDS-UNDERGROUND COAL MINES Electrical Equipment-General § 75.509 Electric power circuit and electric equipment;...

2010-07-01

430

30 CFR 77.500 - Electric power circuits and electric equipment; deenergization.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 2012-07-01 false Electric power circuits and electric equipment; deenergization. 77.500...UNDERGROUND COAL MINES Electrical Equipment-General § 77.500 Electric power circuits and electric equipment;...

2012-07-01

431

30 CFR 75.509 - Electric power circuit and electric equipment; deenergization.  

Code of Federal Regulations, 2014 CFR

...2014-07-01 2014-07-01 false Electric power circuit and electric equipment; deenergization. 75.509...STANDARDS-UNDERGROUND COAL MINES Electrical Equipment-General § 75.509 Electric power circuit and electric equipment;...

2014-07-01

432

30 CFR 75.509 - Electric power circuit and electric equipment; deenergization.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Electric power circuit and electric equipment; deenergization. 75.509...STANDARDS-UNDERGROUND COAL MINES Electrical Equipment-General § 75.509 Electric power circuit and electric equipment;...

2013-07-01

433

30 CFR 77.500 - Electric power circuits and electric equipment; deenergization.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Electric power circuits and electric equipment; deenergization. 77.500...UNDERGROUND COAL MINES Electrical Equipment-General § 77.500 Electric power circuits and electric equipment;...

2010-07-01

434

30 CFR 75.509 - Electric power circuit and electric equipment; deenergization.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 2012-07-01 false Electric power circuit and electric equipment; deenergization. 75.509...STANDARDS-UNDERGROUND COAL MINES Electrical Equipment-General § 75.509 Electric power circuit and electric equipment;...

2012-07-01

435

Electricity Case: Statistical Analysis of Electric Power Outages  

E-print Network

. The duration data suggest a more complicated trend; an analysis of duration per incident over time using for overdispersion in the data, were used. For the number of incidents over time a seasonal analysis suggestsElectricity Case: Statistical Analysis of Electric Power Outages CREATE Report Jeffrey S. Simonoff

Wang, Hai

436

Electric Power Controller for Steering Wheel Management in Electric Cars  

E-print Network

of driverless car traveling around the cities is a utopia. However, some advances in this way have been achievedElectric Power Controller for Steering Wheel Management in Electric Cars Vicente Milanés, Joshué}@iai.csic.es Abstract- driverless driving is one of the most interesting topics in the field of the intelligent

Paris-Sud XI, Université de

437

ELECTRICAL POWER SYSTEM DESCRIPTION DOCUMENT  

SciTech Connect

The purpose of this revision of the System Description Document (SDD) is to establish requirements that drive the design of the electrical power system and their bases to allow the design effort to proceed to License Application. This SDD is a living document that will be revised at strategic points as the design matures over time. This SDD identifies the requirements and describes the system design as they exist at this time, with emphasis on those attributes of the design provided to meet the requirements. This SDD has been developed to be an engineering tool for design control. Accordingly, the primary audience are design engineers. This type of SDD leads and follows the design process. It leads the design process with regard to the flow down of upper tier requirements onto the system. Knowledge of these requirements is essential to performing the design process. This SDD follows the design with regard to the description of the system. The description provided in the SDD is a reflection of the results of the design process to date. Functional and operational requirements applicable to this system are obtained from ''Project Functional and Operational Requirements'' (F&OR) (Siddoway, 2003). Other requirements to support the design process have been taken from higher level requirements documents such as ''Project Design Criteria Document'' (PDC) (Doraswamy 2004), the fire hazards analyses, and the preclosure safety analysis. The above mentioned low-level documents address ''Project Requirements Document'' (PRD) (Canori and Leitner 2003) requirements. This SDD includes several appendices with supporting information. Appendix B lists key system charts, diagrams, drawings, and lists; and Appendix C is a list of system procedures.

M. Maniyar

2004-06-22

438

Electric power monthly, May 1996  

SciTech Connect

This publication presents monthly electricity statistics for a wide audience including Congress, Federal and Stage agencies, the electric utility industry, and the general public. Purpose is to provide energy decisionmakers with accurate and timely information that may be used in forming various perspectives on electric issues that lie ahead. EIA collected the information to fulfill its data collection and dissemination responsibilities in Federal Energy Administration Act of 1974 (Public Law 93-275) as amended.

NONE

1996-05-01

439

Electric Power monthly, November 1996  

SciTech Connect

This publication presents monthly electricity statistics for a wide audience including Congress, Federal and state agencies, the electric utility industry, and the general public. Purpose is to provide energy decisionmakers with accurate and timely information that may be used in forming various perspectives on electric issues that lie ahead. EIA collected the information in this report to fulfill its data collection and dissemination responsibilities as specified in the Federal Energy Administration Act of 1974 (Public Law 93-275) as amended.

NONE

1996-11-01

440

Electrical voltages and resistances measured to inspect metallic cased wells and pipelines  

DOEpatents

A cased well in the earth is electrically energized with A.C. current. Voltages are measured from three voltage measurement electrodes in electrical contact with the interior of the casing while the casing is electrically energized. In a measurement mode, A.C. current is conducted from a first current carrying electrode within the cased well to a remote second current carrying electrode located on the surface of the earth. In a calibration mode, current is passed from the first current carrying electrode to a third current carrying electrode located vertically at a different position within the cased well, where the three voltage measurement electrodes are located vertically in between the first and third current carrying electrodes. Voltages along the casing and resistances along the casing are measured to determine wall thickness and the location of any casing collars present so as to electrically inspect the casing. Similar methods are employed to energize a pipeline to measure the wall thickness of the pipeline and the location of pipe joints to electrically inspect the pipeline.

Vail, III, William Banning (Bothell, WA); Momii, Steven Thomas (Seattle, WA)

2001-01-01

441

Electrical voltages and resistances measured to inspect metallic cased wells and pipelines  

DOEpatents

A cased well in the earth is electrically energized with A.C. current. Voltages are measured from three voltage measurement electrodes in electrical contact with the interior of the casing while the casing is electrically energized. In a measurement mode, A.C. current is conducted from a first current carrying electrode within the cased well to a remote second current carrying electrode located on the surface of the earth. In a calibration mode, current is passed from the first current carrying electrode to a third current carrying electrode located vertically at a different position within the cased well, where the three voltage measurement electrodes are located vertically in between the first and third current carrying electrodes. Voltages along the casing and resistances along the casing are measured to determine wall thickness and the location of any casing collars present so as to electrically inspect the casing. Similar methods are employed to energize a pipeline to measure the wall thickness of the pipeline and the location of pipe joints to electrically inspect the pipeline.

Vail III, William Banning; Momii, Steven Thomas

2003-06-10

442

Electrical voltages and resistances measured to inspect metallic cased wells and pipelines  

DOEpatents

A cased well in the earth is electrically energized with A.C. current. Voltages are measured from three voltage measurement electrodes in electrical contact with the interior of the casing while the casing is electrically energized. In a measurement mode, A.C. current is conducted from a first current carrying electrode within the cased well to a remote second current carrying electrode located on the surface of the earth. In a calibration mode, current is passed from the first current carrying electrode to a third current carrying electrode located vertically at a different position within the cased well, where the three voltage measurement electrodes are located vertically in between the first and third current carrying electrodes. Voltages along the casing and resistances along the casing are measured to determine wall thickness and the location of any casing collars present so as to electrically inspect the casing. Similar methods are employed to energize a pipeline to measure the wall thickness of the pipeline and the location of pipe joints to electrically inspect the pipeline.

Vail, III, William Banning (Bothell, WA); Momii, Steven Thomas (Seattle, WA)

2000-01-01

443

Power Electronics and Motor Drives in Electric, Hybrid Electric, and Plug-In Hybrid Electric Vehicles  

Microsoft Academic Search

With the requirements for reducing emissions and improving fuel economy, automotive companies are developing electric, hybrid electric, and plug-in hybrid electric vehicles. Power electronics is an enabling technology for the development of these environmentally friendlier vehicles and implementing the advanced electrical architectures to meet the demands for increased electric loads. In this paper, a brief review of the current trends

Ali Emadi; Young Joo Lee; Kaushik Rajashekara

2008-01-01

444

Manager's guide to electrical power quality  

SciTech Connect

Electronic equipment has become exceedingly sensitive to the electrical environment. Industry standards to cope with this sensitivity have not been available when needed. Therefore, the term power quality has emerged as a catch-all to explain almost any malfunction of electronic equipment. When a malfunction occurs, for whatever reason, power quality can be invoked to make the power system the scapegoat and the equipment, or its installation, blameless. The power quality syndrome includes such issues as grounding, radio interference, transients, outages, harmonics, etc. Power compatibility or electrical environment compatibility (EEC) would be a more objective term to substitute for power quality. The sensitivity of today's electronic equipment arises from the equipment designers' lack of understanding and concern for the realities of the electrical environment and, to some extent, the utilities' lack of concern of the users' application problems. Consequently, to avoid process interruptions, the user's manager must mediate between the equipment and the power system. The manager must insure that specifications exist for both the equipment and all facets of the plant electrical environment, along with test procedures to insure that these specifications are met. The objective of this article is to show how a manager can handle EEC and, thus, avoid costly redesigns and down time of electrical equipment. Common fallacies, tools for defining the electrical equipment. Common fallacies, tools for defining the electrical environment and some applicable standards (existing and emerging) will also be discussed.

Ludbrook, A. (Ludbrook and Associates, Dundas, Ontario (Canada))

1993-05-01

445

Novel High-Voltage, High-Power Piezoelectric Transformer Developed and Demonstrated for Space Communications Applications  

NASA Technical Reports Server (NTRS)

Improvements in individual piezoelectric transformer (PT) performance and the combination of these PTs in a unique modular topology under a Phase I contract with the NASA Glenn Research Center have enabled for the first time the simultaneous achievement of both high voltage and high power at much higher levels than previously obtained with any PT. Feasibility was demonstrated by a prototype transformer (called a Tap-Soner), which is shown in the preceding photograph as part of a direct-current to direct-current (dc-dc) converter having two outputs rated at 1.5 kV/5 W and 4.5 kV/20 W. The power density of 3.5 W/cm3 is significantly lower than for magnetic transformers with the same voltage and power output. This development, which is being done under a Small Business Innovation Research (SBIR) contract by Face Electronics, LC (Norfolk, VA), is based on improvements in the materials and design of Face's basic patented Transoner-T3 PT, shown in the left in the following figure. The T3 PT is most simply described as a resonant multilayer transducer where electrical energy at the input section is efficiently mechanically coupled to the output section, which then vibrates in a fundamental longitudinal mode to generate a high gain in voltage. The piezoelectric material used is a modified lead-zirconium-titanate-based ceramic. One of the significant improvements in PT design was the incorporation of a symmetrical double input layer, shown on the right in the following figure, which eliminated the lossy bending vibration modes characteristic of a single input layer. The performance of the improved PT was optimized to 1.5 kV/5 W. The next step was devising a way to combine the individual PTs in a modular circuit topology needed to achieve the desired high voltage and power output. Since the optimum performance of the individual PT occurs at resonance, the most efficient operation of the modular transformer was achieved by using a separate drive circuit for each PT. The output section consists of a separate output rectifier for each PT connected in series.

Carazo, Alfredo V.; Wintucky, Edwin G.

2004-01-01

446

Educational Electrical Appliance Power Meter and Logger  

ERIC Educational Resources Information Center

The principles behind two different designs of inductive power meter are presented. They both make use of the microphone input of a computer which, together with a custom-written program, can record the instantaneous power of a domestic electrical appliance. The device can be built quickly and can be calibrated with reference to a known power

Nunn, John

2013-01-01

447

SITE ELECTRICAL POWER SYSTEM DESCRIPTION DOCUMENT  

Microsoft Academic Search

The Site Electrical Power System receives and distributes utility power to all North Portal site users. The major North Portal users are the Protected Area including the subsurface facility and Balance of Plant areas. The system is remotely monitored and controlled from the Surface Operations Monitoring and Control System. The system monitors power quality and provides the capability to transfer

E. P. McCann

1999-01-01

448

Tidal energy in electric power systems  

Microsoft Academic Search

This paper discusses the uses and advantages of tidal energy in restructured power systems. The paper defines the resources as well as the ways in which tidal energy is converted into electricity. The paper also reviews a few tidal power projects around the world. It also shows the working of hydro tidal power plant. A comparative review of renewable energy

S. Sheth; M. Shahidehpour

2005-01-01

449

EE 3410 Electric Power Instructor: Ernest Mendrela  

E-print Network

1 1 EE ­ 3410 Electric Power Fall 2003 Instructor: Ernest Mendrela TRANSFORMERS 1. MAGNETIC CIRCUIT, · There is an ideal magnetic circuit of the iron core with no power losses in it, · There is no leakage flux, what loop of B-H characteristic There is another source of power loss in the magnetic core too

Koppelman, David M.

450

The Fifth Northwest Electric Power  

E-print Network

of under-investment in generation and conservation; a deeply flawed electricity market design in Califor- nia; unethical and illegal actions by some of the participants in that market, and the second concerns about global climate change pose new uncertainties for resource choices. The wholesale electric

451

Neurological Complication After Low-Voltage Electric Injury: A Case Report  

PubMed Central

Electrical shock can result in neurological complications, involving both peripheral and central nervous systems, which may present immediately or later on. However, delayed neurological complications caused by low-voltage electric shock are rarely reported. Here, a case of a man suffering from weakness and aphasia due to the delayed-onset of the peripheral nerve injury and ischemic stroke following an electrical shock is presented. Possible mechanisms underlying the neurological complications include thermal injury to perineural tissue, overactivity of the sympathetic nervous system, vascular injury, and histological or electrophysiological changes. Moreover, vasospasms caused by low-voltage alternating current may predispose individuals to ischemic stroke. Therefore, clinicians should consider the possibility of neurological complications, even if the onset of the symptoms is delayed, and should perform diagnostic tests, such as electrophysiology or imaging, when patients present with weakness following an electric injury. PMID:24855625

Kim, Ha Min; Ko, Yeong-A; Kim, Joon Sung; Lim, Seong Hoon

2014-01-01

452

Contactless measurement of electrical parameters and estimation of current-voltage characteristics of Si solar cells using the illumination intensity dependence of lock-in carrierography (photoluminescence) images  

NASA Astrophysics Data System (ADS)

A combined theoretical and experimental approach is reported using spectrally windowed lock-in carrierography imaging (lock-in photoluminescence) under variable illumination intensity to provide quantitative contactless measurements of key electrical parameters (photogenerated current density, Jg, open circuit voltage, VOC, and maximum power voltage, Vm) of multicrystalline silicon (m-Si) solar cells in very good agreement with standard electrical measurements. The method is based on a recently developed photocarrier radiative recombination current flux relation which links the optical and electrical characteristics of solar cells. In addition, this approach is shown to yield non-contact all-optical estimates of the solar-cell current-voltage characteristics with the conventional variable load resistance replaced by variable laser intensity.

Liu, Junyan; Melnikov, Alexander; Mandelis, Andreas

2013-09-01

453

Verification of voltage/frequency requirement for emergency diesel generator in nuclear power plant using dynamic modeling  

SciTech Connect

One major cause of the plant shutdown is the loss of electrical power. The study is to comprehend the coping action against station blackout including emergency diesel generator, sequential loading of safety system and to ensure that the emergency diesel generator should meet requirements, especially voltage and frequency criteria using modeling tool. This paper also considered the change of the sequencing time and load capacity only for finding electrical design margin. However, the revision of load list must be verified with safety analysis. From this study, it is discovered that new load calculation is a key factor in EDG localization and in-house capability increase.

Hur, Jin-Suk; Roh, Myung- Sub [KEPCO International Nuclear Graduate School, 1456-1 Shinam-ri, Seosaeng-myeon, Ulju-gun, Ulsan, 689-882 (Korea, Republic of)

2014-02-12

454

Topics in high voltage pulsed power plasma devices and applications  

NASA Astrophysics Data System (ADS)

Pulsed power technology is one of the tools that is used by scientists and engineers nowadays to produce gas plasmas. The transient ultra high power is able to provide a huge pulse of energy which is sometimes greater than the ionization energy of the gas, and therefore separates the ions and electrons to form the plasma. Sometimes, the pulsed power components themselves are plasma devices. For example, the gas type switches can "turn on" the circuit by creating the plasma channel between the switch electrodes. Mini Back Lighted Thyratron, or as we call it, mini-BLT, is one of these gas type plasma switches. The development of the reduced size and weight "mini-BLT" is presented in this dissertation. Based on the operation characteristics testing of the mini-BLT, suggestions of optimizing the design of the switch are proposed. All the factors such as the geometry of the hollow electrodes and switch housing, the gas condition, the optical triggering source, etc. are necessary to consider when we design and operate the mini-BLT. By reducing the diameter of the cylindrical gas path between the electrodes in the BLT, a novel high density plasma source is developed, producing the plasma in the "squeezed" capillary. The pulsed power generator, of course, is inevitably used to provide the ionization energy for hydrogen gas sealed in the capillary. Plasma diagnostics are necessarily analyzed and presented in detail to properly complete and understand the capillary plasma. This high density plasma source (1019 cm-3) has the potential applications in the plasma wakefield accelerator. The resonant oscillation behavior of the particles in plasmas allows for dynamically generated accelerating electric fields that have orders of magnitude larger than those available in the conventional RF accelerators. Finally, the solid state switches are introduced as a comparison to the gas type switch. Pulsed power circuit topologies such as the Marx Bank, magnetic pulse compression and diode opening are used to accomplish the pulse generator design. Their applications for the transient plasma car engine combustion and bio-medical skin cancer cell treatments are also introduced.

Chen, Hao

455

Measurements of induced voltages and currents in a distribution power line and associated atmospheric parameters  

NASA Technical Reports Server (NTRS)

The frequency and intensity of thunderstorms around the Kennedy Space Center (KSC) has affected scheduled launch, landing, and other ground operations for many years. In order to protect against and provide safe working facilities, KSC has performed and hosted several studies on lightning phenomena. For the reasons mentioned above, KSC has established the Atmospheric Science Field Laboratory (ASFL). At these facilities KSC launches wire-towing rockets into thunderstorms to trigger natural lightning to the launch site. A program named Rocket Triggered Lightning Program (RTLP) is being conducted at the ASFL. This report calls for two of the experiments conducted in the summer 1988 Rocket Triggered Lightning Program. One experiment suspended an electric field mill over the launching areas from a balloon about 500 meters high to measure the space charges over the launching area. The other was to connect a waveform recorder to a nearby distribution power line to record currents and voltages wave forms induced by natural and triggered lightning.

Santiago-Perez, Julio

1988-01-01

456

Measurements of induced voltages and currents in a distribution power line and associated atmospheric parameters  

NASA Astrophysics Data System (ADS)

The frequency and intensity of thunderstorms around the Kennedy Space Center (KSC) has affected scheduled launch, landing, and other ground operations for many years. In order to protect against and provide safe working facilities, KSC has performed and hosted several studies on lightning phenomena. For the reasons mentioned above, KSC has established the Atmospheric Science Field Laboratory (ASFL). At these facilities KSC launches wire-towing rockets into thunderstorms to trigger natural lightning to the launch site. A program named Rocket Triggered Lightning Program (RTLP) is being conducted at the ASFL. This report calls for two of the experiments conducted in the summer 1988 Rocket Triggered Lightning Program. One experiment suspended an electric field mill over the launching areas from a balloon about 500 meters high to measure the space charges over the launching area. The other was to connect a waveform recorder to a nearby distribution power line to record currents and voltages wave forms induced by natural and triggered lightning.

Santiago-Perez, Julio

1988-10-01

457

Current, voltage and temperature distribution modeling of light-emitting diodes based on electrical and thermal circuit analysis  

NASA Astrophysics Data System (ADS)

We demonstrate a modeling method based on the three-dimensional electrical and thermal circuit analysis to extract current, voltage and temperature distributions of light-emitting diodes (LEDs). In our model, the electrical circuit analysis is performed first to extract the current and voltage distributions in the LED. Utilizing the result obtained from the electrical circuit analysis as distributed heat sources, the thermal circuit is set up by using the duality between Fourier's law and Ohm's law. From the analysis of the thermal circuit, the temperature distribution at each epitaxial film is successfully obtained. Comparisons of experimental and simulation results are made by employing an InGaN/GaN multiple-quantum-well blue LED. Validity of the electrical circuit analysis is confirmed by comparing the light distribution at the surface. Since the temperature distribution at each epitaxial film cannot be obtained experimentally, the apparent temperature distribution is compared at the surface of the LED chip. Also, experimentally obtained average junction temperature is compared with the value calculated from the modeling, yielding a very good agreement. The analysis method based on the circuit modeling has an advantage of taking distributed heat sources as inputs, which is essential for high-power devices with significant self-heating.

Yun, J.; Shim, J.-I.; Shin, D.-S.

2013-08-01

458

An ILP algorithm for post-floorplanning voltage-island generation considering power-network planning  

Microsoft Academic Search

Power optimization is a crucial concern for modern circuit designs. Multiple supply voltages (MSV's) provide an effective technique for the power optimization. This paper addresses the voltage-island generation problem for MSV designs at the post-floorplanning stage. We first present a general formulation of this problem that considers level-shifter planning and power-network routing resources. Without loss of solution quality, we propose

Wan-ping Lee; Hung-yi Liu; Yao-wen Chang

2007-01-01

459

Net energy analysis: Powerful tool for selecting electric power options  

NASA Astrophysics Data System (ADS)

A number of net energy analysis studies have been conducted in recent years for electric power production from coal, oil and uranium fuels; synthetic fuels from coal and oil shale; and heat and electric power from solar energy. This technique is an excellent indicator of investment costs, environmental impact and potential economic competitiveness of alternative electric power systems for energy planners from the Eastern European countries considering future options. Energy conservation is also important to energy planners and the net energy analysis technique is an excellent accounting system on the extent of energy resource conservation. The author proposes to discuss the technique and to present the results of his studies and others in the field. The information supplied to the attendees will serve as a powerful tool to the energy planners considering their electric power options in the future.

Baron, S.

460

Combined dynamic voltage scaling and adaptive body biasing for lower power microprocessors under dynamic workloads  

Microsoft Academic Search

Dynamic voltage scaling (DVS) reduces the power consumption of processors when peak performance is unnecessary. However, the achievable power savings by DVS alone is becoming limited as leakage power increases. In this paper, we show how the simultaneous use of adaptive body biasing (ABB) and DVS can be used to reduce power in high-performance processors. Analytical models of the leakage

Steven M. Martin; Krisztian Flautner; Trevor N. Mudge; David Blaauw

2002-01-01

461

Control Strategy of Active Power Filters Using Multiple Voltage-Source PWM Converters  

Microsoft Academic Search

The control strategy of active power filters using switching devices is proposed on the basis of the instantaneous reactive power theory. This aims at excellent compensation characteristics in transient states as well as steady states. The active power filter is developed, of which the power circuit consists of quadruple voltage-source PWM converters. As the result, interesting compensation characteristics were verified

Hirofumi Akagi; Akira Nabae; Satoshi Atoh

1986-01-01

462

IEEE Trans. on Power Electronics, 2008 Effect of Supply Voltage Harmonics  

E-print Network

IEEE Trans. on Power Electronics, 2008 Effect of Supply Voltage Harmonics on IRP - Based Switching Compensator Control Leszek S. Czarnecki, Fellow, IEEE Abstract--The Instantaneous Reactive Power (IRP) p from the instantaneous reactive power, also the alternating component of the instantaneous active power

Czarnecki, Leszek S.

463

Electrically silent divalent cation entries in resting and active voltage-controlled muscle fibers  

E-print Network

1 Electrically silent divalent cation entries in resting and active voltage-controlled muscle 1, CNRS UMR 5123, Villeurbanne, France Running title: Mn2+ entry and current in muscle cells to enter skeletal muscle at rest and during activity. Except for the well characterized Ca2+ entry through

Paris-Sud XI, Université de

464

Use of low voltage electric therapy in the treatment of psoriasis  

Microsoft Academic Search

The physical agents used for the treatment of psoriasis include ultraviolet light, ultrasound [3] and hyperthermia [5]. These have achieved variable beneficial effects when used alone or with additional medical treatment. This paper discusses a new method for the treatment of psoriasis which involves applying a low voltage electric current to the whole body. The treatment is found to have

O. Fakhri

1990-01-01

465

Low Voltage Alarm Apprenticeship. Related Training Modules. 2.1-5.3 Electricity/Electronics.  

ERIC Educational Resources Information Center

This packet of 29 learning modules on electricity/electronics is 1 of 8 such packets developed for apprenticeship training for low voltage alarm. Introductory materials are a complete listing of all available modules and a supplementary reference list. Each module contains some or all of these components: goal, performance indicators, study guide…

Lane Community Coll., Eugene, OR.

466

Electric utility of the year for 1984: Potomac Electric Power  

SciTech Connect

High performance, efficiency improvements, a modest construction program, a clear balance sheet, and an effort to expend power plant life were among the qualities that earned Potomac Electric Power (PEPCO) the title of 1984 Utility of the Year. Other key elements in the utility's selection were its strategy for purchasing power, a load management plan, diversified investments into subsidiary businesses, community concern that considers the aesthetics of transmission facilities, and its interest in personnel development, especially among minorities. 3 figures.

Not Available

1984-11-01

467

Electric power annual 1989. [Contains glossary  

SciTech Connect

This publication presents a summary of electric utility statistics at the national, regional and state levels. The Industry At A Glance'' section presents a profile of the electric power industry ownership and performance; a review of key statistics for the year; and projections for various aspects of the electric power industry through 2010. Subsequent sections present data on generating capability, including proposed capability additions; net generation; fossil-fuel statistics; electricity sales, revenue and average revenue per kilowatthour sold; financial statistics; environmental statistics; and electric power transactions. In addition, the appendices provide supplemental data on major disturbances and unusual occurrences. Each section contains related text and tables and refers the reader to the appropriate publication that contains more detailed data on the subject matter. 24 figs., 57 tabs.

Not Available

1991-01-17

468

21 CFR 868.5710 - Electrically powered oxygen tent.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Electrically powered oxygen tent. 868.5710 Section 868.5710... § 868.5710 Electrically powered oxygen tent. (a) Identification. An electrically powered oxygen tent is a device that encloses a...

2010-04-01

469

21 CFR 868.5710 - Electrically powered oxygen tent.  

Code of Federal Regulations, 2014 CFR

...2014-04-01 false Electrically powered oxygen tent. 868.5710 Section 868.5710... § 868.5710 Electrically powered oxygen tent. (a) Identification. An electrically powered oxygen tent is a device that encloses a...

2014-04-01

470

21 CFR 868.5710 - Electrically powered oxygen tent.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 false Electrically powered oxygen tent. 868.5710 Section 868.5710... § 868.5710 Electrically powered oxygen tent. (a) Identification. An electrically powered oxygen tent is a device that encloses a...

2011-04-01

471

Power coupling and electrical characterization of a radio-frequency micro atmospheric pressure plasma jet  

NASA Astrophysics Data System (ADS)

We propose an efficient RF power coupling scheme for a micro atmospheric pressure plasma jet operating in helium. The discharge gap is used as a resonant element in a series LC circuit. In resonance, the voltage across the discharge gap is amplified and the ignition of the plasma is enabled with the input RF power as low as 0.5 W. High power coupling efficiency and simplicity of the circuit allow accurate electrical characterization of the discharge. Systematic measurements of the dissipated power as a function of the applied voltage are reported for the discharge operating in helium with molecular admixtures of N2 and O2.

Marinov, D.; Braithwaite, N. St. J.

2014-12-01

472

Hysteresis, Phase Transitions and Dangerous Transients in Electrical Power Distribution Systems  

E-print Network

The majority of dynamical studies in power systems focus on the high voltage transmission grids where models consider large generators interacting with crude aggregations of individual small loads. However, new phenomena have been observed indicating that the spatial distribution of collective, nonlinear contribution of these small loads in the low-voltage distribution grid is crucial to outcome of these dynamical transients. To elucidate the phenomenon, we study the dynamics of voltage and power flows in a spatially-extended distribution feeder (circuit) connecting many asynchronous induction motors and discover that this relatively simple 1+1 (space+time) dimensional system exhibits a plethora of nontrivial spatio-temporal effects, some of which may be dangerous for power system stability. Long-range motor-motor interactions mediated by circuit voltage and electrical power flows result in coexistence and segregation of spatially-extended phases defined by individual motor states--a "normal" state where the ...

Duclut, Charlie; Chertkov, Michael

2012-01-01

473

Parabolic Trough Solar Thermal Electric Power Plants  

SciTech Connect

Although many solar technologies have been demonstrated, parabolic trough solar thermal electric power plant technology represents one of the major renewable energy success stories of the last two decades.

Not Available

2003-06-01