High Speed Solid State Circuit Breaker
NASA Technical Reports Server (NTRS)
Podlesak, Thomas F.
1993-01-01
The U.S. Army Research Laboratory, Fort Monmouth, NJ, has developed and is installing two 3.3 MW high speed solid state circuit breakers at the Army's Pulse Power Center. These circuit breakers will interrupt 4160V three phase power mains in no more than 300 microseconds, two orders of magnitude faster than conventional mechanical contact type circuit breakers. These circuit breakers utilize Gate Turnoff Thyristors (GTO's) and are currently utility type devices using air cooling in an air conditioned enclosure. Future refinements include liquid cooling, either water or two phase organic coolant, and more advanced semiconductors. Each of these refinements promises a more compact, more reliable unit.
Study of feasibility of solid-state electric switch gear for aircraft and spacecraft
NASA Technical Reports Server (NTRS)
Buchanan, E.; Waddington, D.
1973-01-01
The design of a solid-state circuit breaker that can be interconnected to a second breaker to form a transfer switch is presented. The breaker operates on a nominal 270-V dc circuit and controls power to loads of up to 15 A. Automatic overload trip is provided as a function of excess energy measured through the breaker and/or excess current through the breaker. After an overload trip, up to nine preprogrammable attempts to reclose may be tried with programmable delays between each attempt. The breaker or switch is remotely controllable. Test data on performance in the laboratory over temperatures from -45 to 100 C are provided. The feasibility of solid-state switch gear has been established.
NASA Technical Reports Server (NTRS)
Gibbs, R. S.
1974-01-01
Solid state power controllers (SSPC's) are to be considered for use as replacements of electromechanical relays and circuit breakers in future spacecraft and aircraft. They satisfy the combined function of both the relay and circuit breaker and can be remotely controlled by small signals, typically 10 mA, 5 to 28 v(dc). They have the advantage over conventional relay/circuit breaker systems in that they can be located near the utilization equipment and the primary ac or dc bus. The low level control, trip indication and status signals can be circuited by small gauge wire for control, computer interface, logic, electrical multiplexing, onboard testing, power management, and distribution purposes. This results in increased system versatility at appreciable weight saving and increased reliability. Conventional systems require the heavy gage load wiring and the control wiring to be routed from the bus to the load to other remote relay contacts, switches, sensors, etc. and to the circuit breaker located in the flight engineer's compartment for purposes of manual reset.
NASA Technical Reports Server (NTRS)
Gibbs, R. S.
1973-01-01
The rationale, analysis, design, breadboarding and testing of the incremental functional requirements are reported that led to the development of prototype 1 and 5 Amp dc and 1 Amp ac solid state power controllers (SSPC's). The SSPC's are to be considered for use as a replacement of electro-mechanical relays and circuit breakers in future spacecraft and aircraft. They satisfy the combined function of both the relay and circuit breaker and can be remotely controlled by small signals, typically 10 mA, 5 to 28 Vdc. They have the advantage over conventional relay/circuit breaker systems in that they can be located near utilization equipment and the primary ac or dc bus. The low level control, trip indication and status signals can be circuited by small guage wire for control, computer interface, logic, electrical multiplexing, unboard testing, and power management and distribution purposes. This results in increased system versatility at appreciable weight saving and increased reliability.
A High Power Solid State Circuit Breaker for Military Hybrid Electric Vehicle Applications
2012-08-01
the SSCB to isolate a fault, breaker opening is latched and can be reset to reclose the breaker via remote logic input. SSCB state and health...rated load current (125 A). Figure 10 shows that after the SSCB detects a fault and opens, it can also be repeatedly reclosed remotely to attempt to
Fault current limiter and alternating current circuit breaker
Boenig, Heinrich J.
1998-01-01
A solid-state circuit breaker and current limiter for a load served by an alternating current source having a source impedance, the solid-state circuit breaker and current limiter comprising a thyristor bridge interposed between the alternating current source and the load, the thyristor bridge having four thyristor legs and four nodes, with a first node connected to the alternating current source, and a second node connected to the load. A coil is connected from a third node to a fourth node, the coil having an impedance of a value calculated to limit the current flowing therethrough to a predetermined value. Control means are connected to the thyristor legs for limiting the alternating current flow to the load under fault conditions to a predetermined level, and for gating the thyristor bridge under fault conditions to quickly reduce alternating current flowing therethrough to zero and thereafter to maintain the thyristor bridge in an electrically open condition preventing the alternating current from flowing therethrough for a predetermined period of time.
Fault current limiter and alternating current circuit breaker
Boenig, H.J.
1998-03-10
A solid-state circuit breaker and current limiter are disclosed for a load served by an alternating current source having a source impedance, the solid-state circuit breaker and current limiter comprising a thyristor bridge interposed between the alternating current source and the load, the thyristor bridge having four thyristor legs and four nodes, with a first node connected to the alternating current source, and a second node connected to the load. A coil is connected from a third node to a fourth node, the coil having an impedance of a value calculated to limit the current flowing therethrough to a predetermined value. Control means are connected to the thyristor legs for limiting the alternating current flow to the load under fault conditions to a predetermined level, and for gating the thyristor bridge under fault conditions to quickly reduce alternating current flowing therethrough to zero and thereafter to maintain the thyristor bridge in an electrically open condition preventing the alternating current from flowing therethrough for a predetermined period of time. 9 figs.
Hybrid Direct-Current Circuit Breaker
NASA Technical Reports Server (NTRS)
Wang, Ruxi (Inventor); Premerlani, William James (Inventor); Caiafa, Antonio (Inventor); Pan, Yan (Inventor)
2017-01-01
A circuit breaking system includes a first branch including at least one solid-state snubber; a second branch coupled in parallel to the first branch and including a superconductor and a cryogenic contactor coupled in series; and a controller operatively coupled to the at least one solid-state snubber and the cryogenic contactor and programmed to, when a fault occurs in the load circuit, activate the at least one solid-state snubber for migrating flow of the electrical current from the second branch to the first branch, and, when the fault is cleared in the load circuit, activate the cryogenic contactor for migrating the flow of the electrical current from the first branch to the second branch.
Direct current hybrid breakers: A design and its realization
NASA Astrophysics Data System (ADS)
Atmadji, Ali Mahfudz Surya
2000-12-01
The use of semiconductors for electric power circuit breakers instead of conventional breakers remains a utopia when designing fault current interrupters for high power networks. The major problems concerning power semiconductor circuit breakers are the excessive heat losses and their sensitivity to transients. However, conventional breakers are capable of dealing with such matters. A combination of the two methods, or so-called `hybrid breakers', would appear to be a solution; however, hybrid breakers use separate parallel branches for conducting the main current and interrupting the short-circuit current. Such breakers are intended for protecting direct current (DC) traction systems. In this thesis hybrid switching techniques for current limitation and purely solidstate current interruption are investigated for DC breakers. This work analyzes the transient behavior of hybrid breakers and compares their operations with conventional breakers and similar solid-state devices in DC systems. Therefore a hybrid breaker was constructed and tested in a specially designed high power test circuit. A vacuum breaker was chosen as the main breaker in the main conducting path; then a commutation path was connected across the vacuum breaker where it provided current limitation and interruption. The commutation path operated only during any current interruption and the process required additional circuits. These included a certain energy storage, overvoltage suppressor and commutation switch. So that when discharging this energy, a controlled counter-current injection could be produced. That counter-current opposed the main current in the breaker by superposition in order to create a forced current-zero. One-stage and two-stage commutation circuits have been treated extensively. This study project contains both theoretical and experimental investigations. A direct current shortcircuit source was constructed capable of delivering power equivalent to a fault. It supplied a direct voltage of 1kVDC which was rectified having been obtained from a 3-phase lOkV/380V supply. The source was successfully tested to deliver a fault current of 7kA with a time constant of 5ms. The hybrid breaker that was developed could provide protection for 750VDC traction systems. The breaker was equipped with a fault- recognizing circuit based on a current level triggering. An electronic circuit was built for this need and was included in the system. It monitored the system continuously and took action by generating trip signals when a fault was recognized. Interruption was followed by a suitable timing of the fast contact separation in the main breaker and the current-zero creation. An electrodynamically driven mechanism was successfully tested having a dead-time of 300μs to separate the main breaker contacts. Furthermore, a maximum peak current injection of RA at a frequency of 500Hz could be obtained in order to produce an artificial current-zero in the vacuum breaker. A successful current interruption with a prospective value of RA was achieved by the hybrid switching technique. In addition, measures were taken to prevent overvoltages. Experimentally, the concept of a hybrid breaker was compared with the functioning of all mechanical (air breaker) and all electronical (IGCT breaker) versions. Although a single stage interrupting method was verified experimentally, two two-stage interrupting methods were analyzed theoretically.
ERIC Educational Resources Information Center
Massachusetts Department of Education, 2008
2008-01-01
This paper reports on the implementation of the Special Education Reimbursement ("Circuit Breaker") Program. Fiscal Year 2007 is the fourth year implementing the Circuit Breaker reimbursement program which provides additional state support for students with disabilities. School districts are eligible for a reimbursement of eligible costs…
NASA Technical Reports Server (NTRS)
Gemin, Paul; Kupiszewski, Tom; Radun, Arthur; Pan, Yan; Lai, Rixin; Zhang, Di; Wang, Ruxi; Wu, Xinhui; Jiang, Yan; Galioto, Steve;
2015-01-01
The purpose of this effort was to advance the selection, characterization, and modeling of a propulsion electric grid for a Turboelectric Distributed Propulsion (TeDP) system for transport aircraft. The TeDP aircraft would constitute a miniature electric grid with 50 MW or more of total power, two or more generators, redundant transmission lines, and multiple electric motors driving propulsion fans. The study proposed power system architectures, investigated electromechanical and solid state circuit breakers, estimated the impact of the system voltage on system mass, and recommended DC bus voltage range. The study assumed an all cryogenic power system. Detailed assumptions within the study include hybrid circuit breakers, a two cryogen system, and supercritical cyrogens. A dynamic model was developed to investigate control and parameter selection.
Research on burnout fault of moulded case circuit breaker based on finite element simulation
NASA Astrophysics Data System (ADS)
Xue, Yang; Chang, Shuai; Zhang, Penghe; Xu, Yinghui; Peng, Chuning; Shi, Erwei
2017-09-01
In the failure event of molded case circuit breaker, overheating of the molded case near the wiring terminal has a very important proportion. The burnout fault has become an important factor restricting the development of molded case circuit breaker. This paper uses the finite element simulation software to establish the model of molded case circuit breaker by coupling multi-physics field. This model can simulate the operation and study the law of the temperature distribution. The simulation results show that the temperature near the wiring terminal, especially the incoming side of the live wire, of the molded case circuit breaker is much higher than that of the other areas. The steady-state and transient simulation results show that the temperature at the wiring terminals is abnormally increased by increasing the contact resistance of the wiring terminals. This is consistent with the frequent occurrence of burnout of the molded case in this area. Therefore, this paper holds that the burnout failure of the molded case circuit breaker is mainly caused by the abnormal increase of the contact resistance of the wiring terminal.
Evaluation of high-voltage, high-power, solid-state remote power controllers for amps
NASA Technical Reports Server (NTRS)
Callis, Charles P.
1987-01-01
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.
Solid-state circuit breaker with current-limiting characteristic using a superconducting coil
Boenig, H.J.
1982-08-16
A thyristor bridge interposes an ac source and a load. A series connected DC source and superconducting coil within the bridge biases the thyristors thereof so as to permit bidirectional ac current flow therethrough under normal operating conditions. Upon a fault condition a control circuit triggers the thyristors so as to reduce ac current flow therethrough to zero in less than two eyeles and to open the bridge thereafter. Upon a temporary overload condition the control circuit triggers the thyristors so as to limit ac current flow therethrough to an acceptable level.
Solid-state circuit breaker with current limiting characteristic using a superconducting coil
Boenig, Heinrich J.
1984-01-01
A thyristor bridge interposes an ac source and a load. A series connected DC source and superconducting coil within the bridge biases the thyristors thereof so as to permit bidirectional ac current flow therethrough under normal operating conditions. Upon a fault condition a control circuit triggers the thyristors so as to reduce ac current flow therethrough to zero in less than two cycles and to open the bridge thereafter. Upon a temporary overload condition the control circuit triggers the thyristors so as to limit ac current flow therethrough to an acceptable level.
Present Status of Power Circuit Breaker and its Future
NASA Astrophysics Data System (ADS)
Yoshioka, Yoshio
Gas circuit breaker and vacuum circuit breaker are the 2 main types of circuit breaker used in extra high voltage and medium voltage networks. After reviewing the history of these circuit breakers, their present status and technologies are described. As for future technology, computation of interrupting phenomena, SF6 gas less apparatus and expectation of the high voltage vacuum circuit breaker are discussed.
A New Test Method of Circuit Breaker Spring Telescopic Characteristics Based Image Processing
NASA Astrophysics Data System (ADS)
Huang, Huimin; Wang, Feifeng; Lu, Yufeng; Xia, Xiaofei; Su, Yi
2018-06-01
This paper applied computer vision technology to the fatigue condition monitoring of springs, and a new telescopic characteristics test method is proposed for circuit breaker operating mechanism spring based on image processing technology. High-speed camera is utilized to capture spring movement image sequences when high voltage circuit breaker operated. Then the image-matching method is used to obtain the deformation-time curve and speed-time curve, and the spring expansion and deformation parameters are extracted from it, which will lay a foundation for subsequent spring force analysis and matching state evaluation. After performing simulation tests at the experimental site, this image analyzing method could solve the complex problems of traditional mechanical sensor installation and monitoring online, status assessment of the circuit breaker spring.
Commutation circuit for an HVDC circuit breaker
Premerlani, William J.
1981-01-01
A commutation circuit for a high voltage DC circuit breaker incorporates a resistor capacitor combination and a charging circuit connected to the main breaker, such that a commutating capacitor is discharged in opposition to the load current to force the current in an arc after breaker opening to zero to facilitate arc interruption. In a particular embodiment, a normally open commutating circuit is connected across the contacts of a main DC circuit breaker to absorb the inductive system energy trapped by breaker opening and to limit recovery voltages to a level tolerable by the commutating circuit components.
Commutation circuit for an HVDC circuit breaker
Premerlani, W.J.
1981-11-10
A commutation circuit for a high voltage DC circuit breaker incorporates a resistor capacitor combination and a charging circuit connected to the main breaker, such that a commutating capacitor is discharged in opposition to the load current to force the current in an arc after breaker opening to zero to facilitate arc interruption. In a particular embodiment, a normally open commutating circuit is connected across the contacts of a main DC circuit breaker to absorb the inductive system energy trapped by breaker opening and to limit recovery voltages to a level tolerable by the commutating circuit components. 13 figs.
Threshold current for fireball generation
NASA Astrophysics Data System (ADS)
Dijkhuis, Geert C.
1982-05-01
Fireball generation from a high-intensity circuit breaker arc is interpreted here as a quantum-mechanical phenomenon caused by severe cooling of electrode material evaporating from contact surfaces. According to the proposed mechanism, quantum effects appear in the arc plasma when the radius of one magnetic flux quantum inside solid electrode material has shrunk to one London penetration length. A formula derived for the threshold discharge current preceding fireball generation is found compatible with data reported by Silberg. This formula predicts linear scaling of the threshold current with the circuit breaker's electrode radius and concentration of conduction electrons.
Biocompatible circuit-breaker chip for thermal management of biomedical microsystems
NASA Astrophysics Data System (ADS)
Luo, Yi; Dahmardeh, Masoud; Takahata, Kenichi
2015-05-01
This paper presents a thermoresponsive micro circuit breaker for biomedical applications specifically targeted at electronic intelligent implants. The circuit breaker is micromachined to have a shape-memory-alloy cantilever actuator as a normally closed temperature-sensitive switch to protect the device of interest from overheating, a critical safety feature for smart implants including those that are electrothermally driven with wireless micro heaters. The device is fabricated in a size of 1.5 × 2.0 × 0.46 mm3 using biocompatible materials and a chip-based titanium package, exhibiting a nominal cold-state resistance of 14 Ω. The breaker rapidly enters the full open condition when the chip temperature exceeds 63 °C, temporarily breaking the circuit of interest to lower its temperature until chip temperature drops to 51 °C, at which the breaker closes the circuit to allow current to flow through it again, physically limiting the maximum temperature of the circuit. This functionality is tested in combination with a wireless resonant heater powered by radio-frequency electromagnetic radiation, demonstrating self-regulation of heater temperature. The developed circuit-breaker chip operates in a fully passive manner that removes the need for active sensor and circuitry to achieve temperature regulation in a target device, contributing to the miniaturization of biomedical microsystems including electronic smart implants where thermal management is essential.
History of Circuit Breakers and Expectations of Japanese Original Development
NASA Astrophysics Data System (ADS)
Yoshioka, Yoshio; Yoshinaga, Kiyoshi; Yanabu, Satoru
This paper studies the history of high voltage circuit breaker engineering. Methods of analysis are (1) to collect facts in regard to its development, (2) to review the history in order to find essential factors and (3) to identify its pros and cons from engineering point of view. The amount of electric power consumption has increased and gradually the circuit breaker concept was developed. At first the oil circuit breakers were developed in Europe and the air circuit breaker and vacuum circuit breaker were developed. Finally the SF6gas circuit breakers are developed together with the gas insulated switchgear and what is next? The future research and development policy is also discussed.
46 CFR 169.670 - Circuit breakers.
Code of Federal Regulations, 2010 CFR
2010-10-01
... Gross Tons § 169.670 Circuit breakers. Each circuit breaker must be of the manually reset type designed for— (a) Inverse time delay; (b) Instantaneous short circuit protection; and (c) Repeated opening of... 46 Shipping 7 2010-10-01 2010-10-01 false Circuit breakers. 169.670 Section 169.670 Shipping COAST...
30 CFR 75.900-1 - Circuit breakers; location.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Circuit breakers; location. 75.900-1 Section 75.900-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY... Alternating Current Circuits § 75.900-1 Circuit breakers; location. Circuit breakers used to protect low-and...
30 CFR 75.800-1 - Circuit breakers; location.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Circuit breakers; location. 75.800-1 Section 75.800-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY... § 75.800-1 Circuit breakers; location. Circuit breakers protecting high-voltage circuits entering an...
30 CFR 77.800-1 - Testing, examination, and maintenance of circuit breakers; procedures.
Code of Federal Regulations, 2010 CFR
2010-07-01
..., examination, and maintenance of circuit breakers; procedures. (a) Circuit breakers and their auxiliary devices protecting high-voltage circuits to portable or mobile equipment shall be tested and examined at least once... circuit breaker and its auxiliary devices, and such repairs or adjustments as are indicated by such tests...
30 CFR 77.809 - Identification of circuit breakers and disconnecting switches.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Identification of circuit breakers and disconnecting switches. 77.809 Section 77.809 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... circuit breakers and disconnecting switches. Circuit breakers and disconnecting switches shall be labeled...
30 CFR 77.809 - Identification of circuit breakers and disconnecting switches.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Identification of circuit breakers and disconnecting switches. 77.809 Section 77.809 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... circuit breakers and disconnecting switches. Circuit breakers and disconnecting switches shall be labeled...
30 CFR 77.809 - Identification of circuit breakers and disconnecting switches.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Identification of circuit breakers and disconnecting switches. 77.809 Section 77.809 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... circuit breakers and disconnecting switches. Circuit breakers and disconnecting switches shall be labeled...
30 CFR 77.809 - Identification of circuit breakers and disconnecting switches.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Identification of circuit breakers and disconnecting switches. 77.809 Section 77.809 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... circuit breakers and disconnecting switches. Circuit breakers and disconnecting switches shall be labeled...
30 CFR 77.809 - Identification of circuit breakers and disconnecting switches.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Identification of circuit breakers and disconnecting switches. 77.809 Section 77.809 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... circuit breakers and disconnecting switches. Circuit breakers and disconnecting switches shall be labeled...
30 CFR 75.601-1 - Short circuit protection; ratings and settings of circuit breakers.
Code of Federal Regulations, 2010 CFR
2010-07-01
... Trailing Cables § 75.601-1 Short circuit protection; ratings and settings of circuit breakers. Circuit breakers providing short circuit protection for trailing cables shall be set so as not to exceed the...
30 CFR 75.800 - High-voltage circuits; circuit breakers.
Code of Federal Regulations, 2010 CFR
2010-07-01
... shall be equipped with devices to provide protection against under-voltage grounded phase, short circuit... 30 Mineral Resources 1 2010-07-01 2010-07-01 false High-voltage circuits; circuit breakers. 75.800... § 75.800 High-voltage circuits; circuit breakers. [Statutory Provisions] High-voltage circuits entering...
Adaptive sequential controller
El-Sharkawi, Mohamed A.; Xing, Jian; Butler, Nicholas G.; Rodriguez, Alonso
1994-01-01
An adaptive sequential controller (50/50') for controlling a circuit breaker (52) or other switching device to substantially eliminate transients on a distribution line caused by closing and opening the circuit breaker. The device adaptively compensates for changes in the response time of the circuit breaker due to aging and environmental effects. A potential transformer (70) provides a reference signal corresponding to the zero crossing of the voltage waveform, and a phase shift comparator circuit (96) compares the reference signal to the time at which any transient was produced when the circuit breaker closed, producing a signal indicative of the adaptive adjustment that should be made. Similarly, in controlling the opening of the circuit breaker, a current transformer (88) provides a reference signal that is compared against the time at which any transient is detected when the circuit breaker last opened. An adaptive adjustment circuit (102) produces a compensation time that is appropriately modified to account for changes in the circuit breaker response, including the effect of ambient conditions and aging. When next opened or closed, the circuit breaker is activated at an appropriately compensated time, so that it closes when the voltage crosses zero and opens when the current crosses zero, minimizing any transients on the distribution line. Phase angle can be used to control the opening of the circuit breaker relative to the reference signal provided by the potential transformer.
An Overview of Dynamic Contact Resistance Measurement of HV Circuit Breakers
NASA Astrophysics Data System (ADS)
Bhole, A. A.; Gandhare, W. Z.
2016-06-01
With the deregulation of the electrical power industry, utilities and service companies are operating in a changing business environment. High voltage circuit breakers are extremely important for the function of modern electric power supply systems. The need to predict the proper function of circuit breaker grew over the years as the transmission networks expanded. The maintenance of circuit breakers deserves special consideration because of their importance for routine switching and for protection of other equipments. Electric transmission system breakups and equipment destruction can occur if a circuit breaker fails to operate because of a lack of preventive maintenance. Dynamic Contact Resistance Measurement (DCRM) is known as an effective technique for assessing the condition of power circuit breakers contacts and operating mechanism. This paper gives a general review about DCRM. It discusses the practical case studies on use of DCRM for condition assessment of high voltage circuit breakers.
30 CFR 77.800 - High-voltage circuits; circuit breakers.
Code of Federal Regulations, 2010 CFR
2010-07-01
... devices to provide protection against under voltage, grounded phase, short circuit and overcurrent. High... 30 Mineral Resources 1 2010-07-01 2010-07-01 false High-voltage circuits; circuit breakers. 77.800... COAL MINES Surface High-Voltage Distribution § 77.800 High-voltage circuits; circuit breakers. High...
30 CFR 75.800-3 - Testing, examination and maintenance of circuit breakers; procedures.
Code of Federal Regulations, 2010 CFR
2010-07-01
... High-Voltage Distribution § 75.800-3 Testing, examination and maintenance of circuit breakers; procedures. (a) Circuit breakers and their auxiliary devices protecting underground high-voltage circuits...
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
2012-01-09
GENI Project: General Atomics is developing a direct current (DC) circuit breaker that could protect the grid from faults 100 times faster than its alternating current (AC) counterparts. Circuit breakers are critical elements in any electrical system. At the grid level, their main function is to isolate parts of the grid where a fault has occurred—such as a downed power line or a transformer explosion—from the rest of the system. DC circuit breakers must interrupt the system during a fault much faster than AC circuit breakers to prevent possible damage to cables, converters and other grid-level components. General Atomics’ high-voltagemore » DC circuit breaker would react in less than 1/1,000th of a second to interrupt current during a fault, preventing potential hazards to people and equipment.« less
Development, Integration and Testing of Automated Triggering Circuit for Hybrid DC Circuit Breaker
NASA Astrophysics Data System (ADS)
Kanabar, Deven; Roy, Swati; Dodiya, Chiragkumar; Pradhan, Subrata
2017-04-01
A novel concept of Hybrid DC circuit breaker having combination of mechanical switch and static switch provides arc-less current commutation into the dump resistor during quench in superconducting magnet operation. The triggering of mechanical and static switches in Hybrid DC breaker can be automatized which can effectively reduce the overall current commutation time of hybrid DC circuit breaker and make the operation independent of opening time of mechanical switch. With this view, a dedicated control circuit (auto-triggering circuit) has been developed which can decide the timing and pulse duration for mechanical switch as well as static switch from the operating parameters. This circuit has been tested with dummy parameters and thereafter integrated with the actual test set up of hybrid DC circuit breaker. This paper deals with the conceptual design of the auto-triggering circuit, its control logic and operation. The test results of Hybrid DC circuit breaker using this circuit have also been discussed.
30 CFR 75.800-4 - Testing, examination, and maintenance of circuit breakers; record.
Code of Federal Regulations, 2010 CFR
2010-07-01
... Underground High-Voltage Distribution § 75.800-4 Testing, examination, and maintenance of circuit breakers... adjustment of all circuit breakers protecting high-voltage circuits which enter any underground area of the...
The 25 kW resonant dc/dc power converter
NASA Technical Reports Server (NTRS)
Robson, R. R.
1983-01-01
The feasibility of processing 25-kW of power with a single, transistorized, series resonant converter stage was demonstrated by the successful design, development, fabrication, and testing of such a device which employs four Westinghouse D7ST transistors in a full-bridge configuration and operates from a 250-to-350 Vdc input bus. The unit has an overall worst-case efficiency of 93.5% at its full rated output of 1000 V and 25 A dc. A solid-state dc input circuit breaker and output-transient-current limiters are included in and integrated into the design. Full circuit details of the converter are presented along with the test data.
Latest Trends of Vacuum Circuit Breaker and Related Technologies
NASA Astrophysics Data System (ADS)
Kozono, Hideaki; Tanimizu, Toru
Vacuum Circuit Breakers (VCBs) have been widely used for medium voltage level, because of their performance: compact size, light weight, maintenance free operations and environment-friendly characteristics. They become most comfortable breakers for our needs from other breakers: oil, air, magnetic blast and gas. In this paper the history of vacuum, and latest trends of circuit breakers and related technologies are described, as well as merits or demerits of using vacuum technologies.
NASA Astrophysics Data System (ADS)
Budzisz, Joanna; Wróblewski, Zbigniew
2016-03-01
The article presents a method of modelling a vaccum circuit breaker in the ATP/EMTP package, the results of the verification of the correctness of the developed digital circuit breaker model operation and its practical usefulness for analysis of overvoltages and overcurrents occurring in commutated capacitive electrical circuits and also examples of digital simulations of overvoltages and overcurrents in selected electrical circuits.
30 CFR 75.809 - Identification of circuit breakers and disconnecting switches.
Code of Federal Regulations, 2012 CFR
2012-07-01
... disconnecting switches. 75.809 Section 75.809 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... High-Voltage Distribution § 75.809 Identification of circuit breakers and disconnecting switches. [Statutory Provisions] Circuit breakers and disconnecting switches underground shall be marked for...
30 CFR 75.809 - Identification of circuit breakers and disconnecting switches.
Code of Federal Regulations, 2010 CFR
2010-07-01
... disconnecting switches. 75.809 Section 75.809 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... High-Voltage Distribution § 75.809 Identification of circuit breakers and disconnecting switches. [Statutory Provisions] Circuit breakers and disconnecting switches underground shall be marked for...
30 CFR 75.809 - Identification of circuit breakers and disconnecting switches.
Code of Federal Regulations, 2011 CFR
2011-07-01
... disconnecting switches. 75.809 Section 75.809 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... High-Voltage Distribution § 75.809 Identification of circuit breakers and disconnecting switches. [Statutory Provisions] Circuit breakers and disconnecting switches underground shall be marked for...
30 CFR 75.809 - Identification of circuit breakers and disconnecting switches.
Code of Federal Regulations, 2013 CFR
2013-07-01
... disconnecting switches. 75.809 Section 75.809 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... High-Voltage Distribution § 75.809 Identification of circuit breakers and disconnecting switches. [Statutory Provisions] Circuit breakers and disconnecting switches underground shall be marked for...
30 CFR 75.809 - Identification of circuit breakers and disconnecting switches.
Code of Federal Regulations, 2014 CFR
2014-07-01
... disconnecting switches. 75.809 Section 75.809 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... High-Voltage Distribution § 75.809 Identification of circuit breakers and disconnecting switches. [Statutory Provisions] Circuit breakers and disconnecting switches underground shall be marked for...
48 CFR 225.7006 - Restriction on air circuit breakers for naval vessels.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 48 Federal Acquisition Regulations System 3 2011-10-01 2011-10-01 false Restriction on air circuit breakers for naval vessels. 225.7006 Section 225.7006 Federal Acquisition Regulations System DEFENSE... on air circuit breakers for naval vessels. ...
48 CFR 225.7006 - Restriction on air circuit breakers for naval vessels.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Restriction on air circuit breakers for naval vessels. 225.7006 Section 225.7006 Federal Acquisition Regulations System DEFENSE... on air circuit breakers for naval vessels. ...
Superconducting dc Current Limiting Vacuum Circuit Breaker
NASA Astrophysics Data System (ADS)
Alferov, D. F.; Akhmetgareev, M. R.; Budovskii, A. I.; Bunin, R. A.; Voloshin, I. F.; Degtyarenko, P. N.; Yevsin, D. V.; Ivanov, V. P.; Sidorov, V. A.; Fisher, L. M.; Tshai, E. V.
Acircuitofadc superconductingfault current limiter witha direct current circuit-breaker fora nominal current 300A is proposed. It includes the 2G high temperature superconducting (HTS) tapes and the high-speed dc vacuum circuit breaker.Thetestresultsof current-limitingcapacityandrecoverytimeof superconductivityafter currentfaultatvoltage upto3 kV are presented.
Automatic recloser circuit breaker integrated with GSM technology for power system notification
NASA Astrophysics Data System (ADS)
Lada, M. Y.; Khiar, M. S. A.; Ghani, S. A.; Nawawi, M. R. M.; Rahim, N. H.; Sinar, L. O. M.
2015-05-01
Lightning is one type of transient faults that usually cause the circuit breaker in the distribution board trip due to overload current detection. The instant tripping condition in the circuit breakers clears the fault in the system. Unfortunately most circuit breakers system is manually operated. The power line will be effectively re-energized after the clearing fault process is finished. Auto-reclose circuit is used on the transmission line to carry out the duty of supplying quality electrical power to customers. In this project, an automatic reclose circuit breaker for low voltage usage is designed. The product description is the Auto Reclose Circuit Breaker (ARCB) will trip if the current sensor detects high current which exceeds the rated current for the miniature circuit breaker (MCB) used. Then the fault condition will be cleared automatically and return the power line to normal condition. The Global System for Mobile Communication (GSM) system will send SMS to the person in charge if the tripping occurs. If the over current occurs in three times, the system will fully trip (open circuit) and at the same time will send an SMS to the person in charge. In this project a 1 A is set as the rated current and any current exceeding a 1 A will cause the system to trip or interrupted. This system also provides an additional notification for user such as the emergency light and warning system.
NASA Astrophysics Data System (ADS)
Wong, Cat S. M.; Snider, L. A.; Lo, Edward W. C.; Chung, T. S.
Switching of induction motors with vacuum circuit breakers continues to be a concern. In this paper the influence on statistical overvoltages of the stochastic characteristics of vacuum circuit breakers, high frequency models of motors and transformers, and network characteristics, including cable lengths and network topology are evaluated and a general view of the overvoltages phenomena is presented. Finally, a real case study on the statistical voltage levels and risk-of-failure resulting from switching of a vacuum circuit breaker in an industrial installation in Hong Kong is presented.
Hydraulic actuator for an electric circuit breaker
Imam, I.
1983-05-17
This actuator comprises a fluid motor having a piston, a breaker-opening space at one side of the piston, and a breaker-closing space at its opposite side. An accumulator freely communicates with the breaker-opening space for supplying pressurized fluid thereto during a circuit breaker opening operation. The breaker-opening space and the breaker-closing space are connected by an impeded flow passage. A pilot valve opens to allow the pressurized liquid in the breaker-closing space to flow to a back chamber of a normally closed main valve to cause the main valve to be opened during a circuit breaker opening operation to release the pressurized liquid from the breaker-closing space. An impeded passage affords communication between the back chamber and a sump located on the opposite side of the main valve from the back chamber. The pilot valve and impeded passage allow rapid opening of the main valve with pressurized liquid from the breaker closing side of the piston. 3 figs.
Hydraulic actuator for an electric circuit breaker
Imam, Imdad [Colonie, NY
1983-01-01
This actuator comprises a fluid motor having a piston, a breaker-opening space at one side of the piston, and a breaker-closing space at its opposite side. An accumulator freely communicates with the breaker-opening space for supplying pressurized fluid thereto during a circuit breaker opening operation. The breaker-opening space and the breaker-closing space are connected by an impeded flow passage. A pilot valve opens to allow the pressurized liquid in the breaker-closing space to flow to a back chamber of a normally closed main valve to cause the main valve to be opened during a circuit breaker opening operation to release the pressurized liquid from the breaker-closing space. An impeded passage affords communication between the back chamber and a sump located on the opposite side of the main valve from the back chamber. The pilot valve and impeded passage allow rapid opening of the main valve with pressurized liquid from the breaker closing side of the piston.
Designing a 25-kilowatt high frequency series resonant
NASA Technical Reports Server (NTRS)
Robson, R. R.
1984-01-01
The feasibility of processing 25 kW of power with a single, transistorized, 20 kHz, series resonant converter stage has been demonstrated by the successful design, development, fabrication, and testing of such a device. It employs four Westinghouse D7ST transistors in a full-bridge configuration and operates from a 250-to-350-Vdc input bus. The unit has an overall worst-case efficiency of 93.5% at its full rated output of 1000 V and 25 A dc. A solid-state dc input circuit breaker and output-transient-current limiters are included in and integrated into the design. Circuit details of the converter are presented along with test data.
46 CFR 111.30-4 - Circuit breakers removable from the front.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 46 Shipping 4 2011-10-01 2011-10-01 false Circuit breakers removable from the front. 111.30-4 Section 111.30-4 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Switchboards § 111.30-4 Circuit breakers removable from the front...
46 CFR 111.30-4 - Circuit breakers removable from the front.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 46 Shipping 4 2014-10-01 2014-10-01 false Circuit breakers removable from the front. 111.30-4 Section 111.30-4 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Switchboards § 111.30-4 Circuit breakers removable from the front...
46 CFR 111.30-4 - Circuit breakers removable from the front.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 46 Shipping 4 2012-10-01 2012-10-01 false Circuit breakers removable from the front. 111.30-4 Section 111.30-4 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Switchboards § 111.30-4 Circuit breakers removable from the front...
46 CFR 111.30-4 - Circuit breakers removable from the front.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 46 Shipping 4 2013-10-01 2013-10-01 false Circuit breakers removable from the front. 111.30-4 Section 111.30-4 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Switchboards § 111.30-4 Circuit breakers removable from the front...
46 CFR 111.30-4 - Circuit breakers removable from the front.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 46 Shipping 4 2010-10-01 2010-10-01 false Circuit breakers removable from the front. 111.30-4 Section 111.30-4 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Switchboards § 111.30-4 Circuit breakers removable from the front...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-02-17
... related detached components; 75.800-4 Testing, examination and maintenance of circuit breakers; record; 75...-4 Testing, examination and maintenance of circuit breakers; record; 75.1001-1 Devices for..., testing, and maintenance; 77.800-2 Testing, examination and maintenance of circuit breakers; record; and...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-02-06
... changes to the market- wide circuit breaker on a pilot basis for a period scheduled to start on February 4... circuit breaker pilot to April 8, 2013 in order for the implementation date for the market-wide circuit..., SR-NASD-98-27, and SR-Phlx-98-15). Once a Rule 11.18 circuit breaker is in effect, trading in all...
78 FR 8659 - Self-Regulatory Organizations; BATS Y-Exchange, Inc.; Notice of Filing and Immediate...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-02-06
... proposed changes to the market- wide circuit breaker on a pilot basis for a period scheduled to start on... circuit breaker pilot to April 8, 2013 in order for the implementation date for the market-wide circuit..., SR-NASD-98-27, and SR-Phlx-98-15). Once a Rule 11.18 circuit breaker is in effect, trading in all...
Hydraulically-activated operating system for an electric circuit breaker
Imam, Imdad; Barkan, Philip
1979-01-01
This operating system comprises a fluid motor having a piston, a breaker-opening space at one side of the piston, and a breaker-closing space at its opposite side. An accumulator freely communicates with the breaker-opening space for supplying pressurized fluid thereto during a circuit-breaker opening operation. A normally-closed valve located on the breaker-closing-side of the piston is openable to release liquid from the breaker-closing space so that pressurized liquid in the breaker-opening space can drive the piston in an opening direction. Means is provided for restoring the valve to its closed position following the circuit-breaker opening operation. An impeded passage affords communication between the accumulator and the breaker-closing space to allow pressurized liquid to flow from the accumulator to the breaker-closing space and develop a pressure therein substantially equal to accumulator pressure when the valve is restored to closed position following breaker-opening. This passage is so impeded that the flow therethrough from the accumulator into the breaker-closing space is sufficiently low during initial opening motion of the piston through a substantial portion of its opening stroke as to avoid interference with said initial opening motion of the piston.
30 CFR 75.800-3 - Testing, examination and maintenance of circuit breakers; procedures.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Testing, examination and maintenance of circuit breakers; procedures. 75.800-3 Section 75.800-3 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... High-Voltage Distribution § 75.800-3 Testing, examination and maintenance of circuit breakers...
Self-consistent radiation-based simulation of electric arcs: II. Application to gas circuit breakers
NASA Astrophysics Data System (ADS)
Iordanidis, A. A.; Franck, C. M.
2008-07-01
An accurate and robust method for radiative heat transfer simulation for arc applications was presented in the previous paper (part I). In this paper a self-consistent mathematical model based on computational fluid dynamics and a rigorous radiative heat transfer model is described. The model is applied to simulate switching arcs in high voltage gas circuit breakers. The accuracy of the model is proven by comparison with experimental data for all arc modes. The ablation-controlled arc model is used to simulate high current PTFE arcs burning in cylindrical tubes. Model accuracy for the lower current arcs is evaluated using experimental data on the axially blown SF6 arc in steady state and arc resistance measurements close to current zero. The complete switching process with the arc going through all three phases is also simulated and compared with the experimental data from an industrial circuit breaker switching test.
Code of Federal Regulations, 2011 CFR
2011-07-01
...-phase alternating current equipment; circuit breakers. 75.900 Section 75.900 Mineral Resources MINE... Low- and medium-voltage circuits serving three-phase alternating current equipment; circuit breakers. [Statutory Provisions] Low- and medium-voltage power circuits serving three-phase alternating current...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-02-06
... Proposed Rule Change to Amend ISE Rule 2102 to Extend the Market-Wide Circuit Breaker Pilot Program January...- wide circuit breaker on a pilot basis for a period that corresponds to the pilot period for the LULD... delay the operative date of the market-wide circuit breaker pilot to April 8, 2013 in order for the...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-02-06
... Change To Delay the Operative Date of Rule 11.20A Regarding Market-Wide Circuit Breakers Due to... the market- wide circuit breakers on a pilot basis for a period scheduled to start on February 4, 2013... changed to April 8, 2013. The proposal would delay the operative date of the market-wide circuit breaker...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-02-06
... adopted the proposed changes to the market-wide circuit breakers on a pilot basis for a period that... to April 8, 2013. The proposal would delay the operative date of the market-wide circuit breaker pilot to April 8, 2013 in order for the implementation date for the market-wide circuit breaker pilot...
NASA Astrophysics Data System (ADS)
Wang, Xiaohua; Rong, Mingzhe; Qiu, Juan; Liu, Dingxin; Su, Biao; Wu, Yi
A new type of algorithm for predicting the mechanical faults of a vacuum circuit breaker (VCB) based on an artificial neural network (ANN) is proposed in this paper. There are two types of mechanical faults in a VCB: operation mechanism faults and tripping circuit faults. An angle displacement sensor is used to measure the main axle angle displacement which reflects the displacement of the moving contact, to obtain the state of the operation mechanism in the VCB, while a Hall current sensor is used to measure the trip coil current, which reflects the operation state of the tripping circuit. Then an ANN prediction algorithm based on a sliding time window is proposed in this paper and successfully used to predict mechanical faults in a VCB. The research results in this paper provide a theoretical basis for the realization of online monitoring and fault diagnosis of a VCB.
Programmable Low-Voltage Circuit Breaker and Tester
NASA Technical Reports Server (NTRS)
Greenfield, Terry
2008-01-01
An instrumentation system that would comprise a remotely controllable and programmable low-voltage circuit breaker plus several electric-circuit-testing subsystems has been conceived, originally for use aboard a spacecraft during all phases of operation from pre-launch testing through launch, ascent, orbit, descent, and landing. The system could also be adapted to similar use aboard aircraft. In comparison with remotely controllable circuit breakers heretofore commercially available, this system would be smaller, less massive, and capable of performing more functions, as needed for aerospace applications.
Optimizing the switching time for 400 kV SF6 circuit breakers
NASA Astrophysics Data System (ADS)
Ciulica, D.
2018-01-01
This paper presents real-time voltage and current analysis for optimizing the wave switching point of the circuit breaker SF6. Circuit Breaker plays an important role in power systems. It provides protection for equipment in embedded stations in transport networks. SF6 Circuit Breaker is very important equipment in Power Systems, which is used for up to 400 kV due to its excellent performance. The controlled switching is used to eliminate transient modes and electrodynamic and dielectric charges in the network at manual switching of capacitor, shunt reactors and power transformers. These effects reduce the reliability and lifetime of the equipment installed on the network, or may lead to erroneous protection.
46 CFR 28.860 - Overcurrent protection and switched circuits.
Code of Federal Regulations, 2010 CFR
2010-10-01
... current carrying conductor must be protected in accordance with its current carrying capacity by a circuit breaker or fuse at the connection to the switchboard or distribution panel bus. (d) Each circuit breaker...
46 CFR 28.860 - Overcurrent protection and switched circuits.
Code of Federal Regulations, 2011 CFR
2011-10-01
... current carrying conductor must be protected in accordance with its current carrying capacity by a circuit breaker or fuse at the connection to the switchboard or distribution panel bus. (d) Each circuit breaker...
NASA Astrophysics Data System (ADS)
Niwa, Yoshimitsu; Matsuzaki, Jun; Yokokura, Kunio
The high-speed vacuum circuit breaker, which forced the fault current to zero was investigated. The test circuit breaker consisted of a vacuum interrupter and a high frequency current source. The vacuum interrupter, which had the axial magnetic field electrode and the disk shape electrode, was tested. The arcing period of the high-speed vacuum circuit breaker is much shorter than that of conventional circuit breaker. The arc behavior of the test electrodes immediately after the contact separation was observed by a high-speed video camcorder. The relation between the current waveform just before the current zero and the interruption ability by varying the high frequency current source was investigated experimentally. The results demonstrate the interruption ability and the arc behavior of the high-speed vacuum circuit breaker. The high current interruption was made possible by the low current period just before the current zero, although the arcing time is short and the arc is concentrated.
Lockout device for high voltage circuit breaker
Kozlowski, Lawrence J.; Shirey, Lawrence A.
1993-01-01
An improved lockout assembly is provided for a circuit breaker to lock the switch handle into a selected switch position. The lockout assembly includes two main elements, each having a respective foot for engaging a portion of the upper housing wall of the circuit breaker. The first foot is inserted into a groove in the upper housing wall, and the second foot is inserted into an adjacent aperture (e.g., a slot) in the upper housing wall. The first foot is slid under and into engagement with a first portion, and the second foot is slid under and into engagement with a second portion of the upper housing wall. At the same time the repsective two feet are placed in engagement with the respective portions of the upper housing wall, two holes, one on each of the respective two main elements of the assembly, are placed in registration; and a locking device, such as a special scissors equipped with a padlock, is installed through the registered holes to secure the lockout assembly on the circuit breaker. When the lockout assembly of the invention is secured on the circuit breaker, the switch handle of the circuit breaker is locked into the selected switch position and prevented from being switched to another switch position.
Lockout device for high voltage circuit breaker
Kozlowski, L.J.; Shirey, L.A.
1993-01-26
An improved lockout assembly is provided for a circuit breaker to lock the switch handle into a selected switch position. The lockout assembly includes two main elements, each having a respective foot for engaging a portion of the upper housing wall of the circuit breaker. The first foot is inserted into a groove in the upper housing wall, and the second foot is inserted into an adjacent aperture (e.g., a slot) in the upper housing wall. The first foot is slid under and into engagement with a first portion, and the second foot is slid under and into engagement with a second portion of the upper housing wall. At the same time the respective two feet are placed in engagement with the respective portions of the upper housing wall, two holes, one on each of the respective two main elements of the assembly, are placed in registration; and a locking device, such as a special scissors equipped with a padlock, is installed through the registered holes to secure the lockout assembly on the circuit breaker. When the lockout assembly of the invention is secured on the circuit breaker, the switch handle of the circuit breaker is locked into the selected switch position and prevented from being switched to another switch position.
46 CFR 111.54-1 - Circuit breakers.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 46 Shipping 4 2013-10-01 2013-10-01 false Circuit breakers. 111.54-1 Section 111.54-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL... breaker must not: (1) Be dependent upon mechanical cooling to operate within its rating; or (2) Have a...
46 CFR 111.54-1 - Circuit breakers.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 46 Shipping 4 2012-10-01 2012-10-01 false Circuit breakers. 111.54-1 Section 111.54-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL... breaker must not: (1) Be dependent upon mechanical cooling to operate within its rating; or (2) Have a...
46 CFR 111.54-1 - Circuit breakers.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 46 Shipping 4 2011-10-01 2011-10-01 false Circuit breakers. 111.54-1 Section 111.54-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL... breaker must not: (1) Be dependent upon mechanical cooling to operate within its rating; or (2) Have a...
46 CFR 111.54-1 - Circuit breakers.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 46 Shipping 4 2010-10-01 2010-10-01 false Circuit breakers. 111.54-1 Section 111.54-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL... breaker must not: (1) Be dependent upon mechanical cooling to operate within its rating; or (2) Have a...
Humidity Control in the U.S. Air Force Aircraft Service Shelter
1988-06-30
printed circuit board control module , terminal boards, and blowt.r, etc.) are off-the-shelf commercial components. Only the humidifier ho:;Ift, I...indication of the shelter RH. - Circuit Breaker: A 20 amp, three pole breaker is providud fur equipment protection. o Water Storage Tank. A stainless...tapped into the shelter’s existing electrical system at the panelboard, on the load side of the 100 Amp main AC circuit breaker. Power is then
Circuit breaker lock out assembly
Gordy, W.T.
1983-05-18
A lock out assembly for a circuit breaker which consists of a generally step-shaped unitary base with an aperture in the small portion of the step-shaped base and a roughly S shaped retaining pin which loops through the large portion of the step-shaped base. The lock out assembly is adapted to fit over a circuit breaker with the handle switch projecting through the aperture, and the retaining pin projecting into an opening of the handle switch, preventing removal.
Circuit breaker lock out assembly
Gordy, Wade T.
1984-01-01
A lock out assembly for a circuit breaker which consists of a generally step-shaped unitary base with an aperture in the small portion of the step-shaped base and a roughly "S" shaped retaining pin which loops through the large portion of the step-shaped base. The lock out assembly is adapted to fit over a circuit breaker with the handle switch projecting through the aperture, and the retaining pin projecting into an opening of the handle switch, preventing removal.
Code of Federal Regulations, 2011 CFR
2011-07-01
... portable or mobile three-phase alternating current equipment; circuit breakers. 77.900 Section 77.900... mobile three-phase alternating current equipment; circuit breakers. Low- and medium-voltage circuits supplying power to portable or mobile three-phase alternating current equipment shall be protected by...
Electrical short circuit and current overload tests on aircraft wiring
NASA Technical Reports Server (NTRS)
Cahill, Patricia
1995-01-01
The findings of electrical short circuit and current overload tests performed on commercial aircraft wiring are presented. A series of bench-scale tests were conducted to evaluate circuit breaker response to overcurrent and to determine if the wire showed any visible signs of thermal degradation due to overcurrent. Three types of wire used in commercial aircraft were evaluated: MIL-W-22759/34 (150 C rated), MIL-W-81381/12 (200 C rated), and BMS 1360 (260 C rated). A second series of tests evaluated circuit breaker response to short circuits and ticking faults. These tests were also meant to determine if the three test wires behaved differently under these conditions and if a short circuit or ticking fault could start a fire. It is concluded that circuit breakers provided reliable overcurrent protection. Circuit breakers may not protect wire from ticking faults but can protect wire from direct shorts. These tests indicated that the appearance of a wire subjected to a current that totally degrades the insulation looks identical to a wire subjected to a fire; however the 'fire exposed' conductor was more brittle than the conductor degraded by overcurrent. Preliminary testing indicates that direct short circuits are not likely to start a fire. Preliminary testing indicated that direct short circuits do not erode insulation and conductor to the extent that ticking faults did. Circuit breakers may not safeguard against the ignition of flammable materials by ticking faults. The flammability of materials near ticking faults is far more important than the rating of the wire insulation material.
High temperature circuit breaker
NASA Technical Reports Server (NTRS)
Edwards, R. N.; Travis, E. F.
1970-01-01
Alternating current circuit breaker is suitable for reliable long-term service at 1000 deg F in the vacuum conditions of outer space. Construction materials are resistant to nuclear radiation and vacuum welding. Service test conditions and results are given.
The original westinghouse circuit breakers, manufactured 7/11/27. Utility room, to ...
The original westinghouse circuit breakers, manufactured 7/11/27. Utility room, to north. - San Bernardino Valley College, Life Science Building, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA
Switching of High-Voltage Cable Lines with Shunt Reactors
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sheskin, E. B., E-mail: evgeniy.sheskin@gmail.com; Evdokunin, G. A.
2016-05-15
The problem of disconnecting high-voltage cable lines with shunt reactors by SF{sub 6} circuit breakers is discussed. In these schemes it is possible to have a significant aperiodic component of the circuit breaker current that can prevent opening of the breaker. The authors propose methods for application to cable transmission lines which they believe will be optimal for ensuring normal disconnects.
Design and experimental results of the 1-T Bitter Electromagnet Testing Apparatus (BETA)
NASA Astrophysics Data System (ADS)
Bates, E. M.; Birmingham, W. J.; Romero-Talamás, C. A.
2018-05-01
The Bitter Electromagnet Testing Apparatus (BETA) is a 1-Tesla (T) technical prototype of the 10 T Adjustable Long Pulsed High-Field Apparatus. BETA's final design specifications are highlighted in this paper which include electromagnetic, thermal, and stress analyses. We discuss here the design and fabrication of BETA's core, vessel, cooling, and electrical subsystems. The electrical system of BETA is composed of a scalable solid-state DC breaker circuit. Experimental results display the stable operation of BETA at 1 T. These results are compared to both analytical design and finite element calculations. Experimental results validate analytical magnet designing methods developed at the Dusty Plasma Laboratory. The theoretical steady state maxima and the limits of BETA's design are explored in this paper.
Design and experimental results of the 1-T Bitter Electromagnet Testing Apparatus (BETA).
Bates, E M; Birmingham, W J; Romero-Talamás, C A
2018-05-01
The Bitter Electromagnet Testing Apparatus (BETA) is a 1-Tesla (T) technical prototype of the 10 T Adjustable Long Pulsed High-Field Apparatus. BETA's final design specifications are highlighted in this paper which include electromagnetic, thermal, and stress analyses. We discuss here the design and fabrication of BETA's core, vessel, cooling, and electrical subsystems. The electrical system of BETA is composed of a scalable solid-state DC breaker circuit. Experimental results display the stable operation of BETA at 1 T. These results are compared to both analytical design and finite element calculations. Experimental results validate analytical magnet designing methods developed at the Dusty Plasma Laboratory. The theoretical steady state maxima and the limits of BETA's design are explored in this paper.
Optimization of the Switch Mechanism in a Circuit Breaker Using MBD Based Simulation
Jang, Jin-Seok; Yoon, Chang-Gyu; Ryu, Chi-Young; Kim, Hyun-Woo; Bae, Byung-Tae; Yoo, Wan-Suk
2015-01-01
A circuit breaker is widely used to protect electric power system from fault currents or system errors; in particular, the opening mechanism in a circuit breaker is important to protect current overflow in the electric system. In this paper, multibody dynamic model of a circuit breaker including switch mechanism was developed including the electromagnetic actuator system. Since the opening mechanism operates sequentially, optimization of the switch mechanism was carried out to improve the current breaking time. In the optimization process, design parameters were selected from length and shape of each latch, which changes pivot points of bearings to shorten the breaking time. To validate optimization results, computational results were compared to physical tests with a high speed camera. Opening time of the optimized mechanism was decreased by 2.3 ms, which was proved by experiments. Switch mechanism design process can be improved including contact-latch system by using this process. PMID:25918740
NASA Astrophysics Data System (ADS)
Takeuchi, Toshie; Nakagawa, Takafumi; Tsukima, Mitsuru; Koyama, Kenichi; Tohya, Nobumoto; Yano, Tomotaka
A new electromagnetically actuated vacuum circuit breaker (VCB) has been designed and developed on the basis of the transient electromagnetic analysis coupled with motion. The VCB has three advanced bi-stable electromagnetic actuators, which control each phase independently. The VCB serves as a synchronous circuit breaker as well as a standard circuit breaker. In this work, the flux delay due to the eddy current is analytically formulated using the delay time constant of the actuator coil current, thereby leading to accurate driving behavior. With this analytical method, the electromagnetic mechanism for a 24kV rated VCB has been optimized; and as a result, the driving energy is reduced to one fifth of that of a conventional VCB employing spring mechanism, and the number of parts is significantly decreased. Therefore, the developed VCB becomes compact, highly reliable and highly durable.
75 FR 82327 - Airworthiness Directives; Dassault-Aviation Model FALCON 7X Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2010-12-30
... wiring, both circuit breakers that supply power to that wiring will trip, causing simultaneous de-power... case a short circuit occurs on a weight-on-wheels (WOW) proximity sensor wiring, both circuit breakers that supply power to that wiring will trip, causing simultaneous de-power of all WOW proximity sensors...
76 FR 24358 - Airworthiness Directives; Dassault-Aviation Model FALCON 7X Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2011-05-02
...-wheels (WOW) proximity sensor wiring, both circuit breakers that supply power to that wiring will trip... sensor wiring, both circuit breakers that supply power to that wiring will trip, causing simultaneous de... robustness against short circuit of the proximity sensors wiring by adding dedicated fuses to each [[Page...
62. VIEW LOOKING NORTHWEST AT THE OIL FILLED CIRCUIT BREAKER ...
62. VIEW LOOKING NORTHWEST AT THE OIL FILLED CIRCUIT BREAKER FOR GENERATOR NUMBER 1. CIRCUIT BREAKERS ARE AUTOMATED SWITCHES WHICH DISCONNECT THE GENERATORS FROM THE LINE WHEN SHORT CIRCUITS OCCUR. WHEN CIRCUITS INVOLVING HIGH CURRENTS AND VOLTAGES ARE BROKEN, THE AIR SURROUNDING MECHANICAL PARTS OF THE SWITCH BECOMES IONIZED AND CONTINUES TO CONDUCT ELECTRIC POWER ACROSS ANY GAP IN THE SWITCH CONTACTS. TO PREVENT THIS AND INSURE A POSITIVE INTERRUPTION OF CURRENT, THE SWITCH CONTACTS ARE IMMERSED IN A CONTAINER OF OIL. THE OIL DOES NOT SUPPORT THE FORMATION OF AN ARC AND EFFECTIVELY CUTS OFF THE CURRENT WHEN THE SWITCH CONTACTS ARE OPENED. - New York, New Haven & Hartford Railroad, Cos Cob Power Plant, Sound Shore Drive, Greenwich, Fairfield County, CT
Interruption of a dry-type transformer in no-load by a vacuum circuit-breaker
NASA Astrophysics Data System (ADS)
Vandenheuvel, W. M. C.; Daalder, J. E.; Boone, M. J. M.; Wilmes, L. A. H.
1983-08-01
Overvoltages generated during interruption of a dry type delta-star connected transformer in no load by a vacuum breaker were studied. During interruption of inrush current 37% of the phase-to-ground overvoltages were 5 pu, and 6% 7 pu. Comparison of experimental and theoretical results using Boyle's model shows no discrepancy for inrush currents and clean overvoltages from the steady-state interruption. Overvoltages due to repetitive reignitions (not covered by Boyle's model) are higher than the calculated values during steady-state switching.
High speed hydraulically-actuated operating system for an electric circuit breaker
Iman, I.
1983-06-07
This hydraulically-actuated operating system comprises a cylinder, a piston movable therein in an opening direction to open a circuit breaker, and an accumulator for supplying pressurized liquid to a breaker-opening piston-actuating space within the cylinder. A normally-closed valve between the accumulator and the actuating space is openable to allow pressurized liquid from the accumulator to flow through the valve into the actuating space to drive the piston in an opening direction. A dashpotting mechanism operating separately from the hydraulic actuating system is provided, thereby reducing flow restriction interference with breaker opening. 3 figs.
High speed hydraulically-actuated operating system for an electric circuit breaker
Iman, Imdad
1983-06-07
This hydraulically-actuated operating system comprises a cylinder, a piston movable therein in an opening direction to open a circuit breaker, and an accumulator for supplying pressurized liquid to a breaker-opening piston-actuating space within the cylinder. A normally-closed valve between the accumulator and the actuating space is openable to allow pressurized liquid from the accumulator to flow through the valve into the actuating space to drive the piston in an opening direction. A dashpotting mechanism operating separately from the hydraulic actuating system is provided, thereby reducing flow restriction interference with breaker opening.
Circuit breaker lockout device
Kozlowski, Lawrence J.; Shirey, Lawrence A.
1992-01-01
An improved lockout assembly for locking a circuit breaker in a selected off or on position is provided. The lockout assembly includes a lock block and a lock pin. The lock block has a hollow interior which fits over the free end of a switch handle of the circuit breaker. The lock block includes at least one hole that is placed in registration with a hole in the free end of the switch handle. A lock tab on the lock block serves to align and register the respective holes on the lock block and switch handle. A lock pin is inserted through the registered holes and serves to connect the lock block to the switch handle. Once the lock block and the switch handle are connected, the position of the switch handle is prevented from being changed by the lock tab bumping up against a stationary housing portion of the circuit breaker. When the lock pin installed, an apertured-end portion of the lock pin is in registration with another hole on the lock block. Then a special scissors conforming to O.S.H.A. regulations can be installed, with one or more padlocks, on the lockout assembly to prevent removal of the lock pin from the lockout assembly, thereby preventing removal of the lockout assembly from the circuit breaker.
Circuit breaker lockout device
Kozlowski, L.J.; Shirey, L.A.
1992-11-24
An improved lockout assembly for locking a circuit breaker in a selected off or on position is provided. The lockout assembly includes a lock block and a lock pin. The lock block has a hollow interior which fits over the free end of a switch handle of the circuit breaker. The lock block includes at least one hole that is placed in registration with a hole in the free end of the switch handle. A lock tab on the lock block serves to align and register the respective holes on the lock block and switch handle. A lock pin is inserted through the registered holes and serves to connect the lock block to the switch handle. Once the lock block and the switch handle are connected, the position of the switch handle is prevented from being changed by the lock tab bumping up against a stationary housing portion of the circuit breaker. When the lock pin installed, an apertured-end portion of the lock pin is in registration with another hole on the lock block. Then a special scissors conforming to O.S.H.A. regulations can be installed, with one or more padlocks, on the lockout assembly to prevent removal of the lock pin from the lockout assembly, thereby preventing removal of the lockout assembly from the circuit breaker. 2 figs.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-02-06
... changes to the market- wide circuit breaker on a pilot basis for a period scheduled to start on February 4... circuit breaker pilot to April 8, 2013 in order for the implementation date for the market-wide circuit...-Amex-98-09, SR-BSE-98-06, SR-CHX-98-08, SR-NASD-98-27, and SR-Phlx-98-15). Once a Rule 11.14 circuit...
37. SAR2, SHOWING OIL CIRCUIT BREAKERS (ABOVE) AND GENERATOR FIELD ...
37. SAR-2, SHOWING OIL CIRCUIT BREAKERS (ABOVE) AND GENERATOR FIELD COIL CONTROL RHEOSTATS (BELOW). SCE negative no. 10331, November 1, 1923. Photograph by G. Haven Bishop. - Santa Ana River Hydroelectric System, SAR-2 Powerhouse, Redlands, San Bernardino County, CA
Use of Fuzzy Logic Systems for Assessment of Primary Faults
NASA Astrophysics Data System (ADS)
Petrović, Ivica; Jozsa, Lajos; Baus, Zoran
2015-09-01
In electric power systems, grid elements are often subjected to very complex and demanding disturbances or dangerous operating conditions. Determining initial fault or cause of those states is a difficult task. When fault occurs, often it is an imperative to disconnect affected grid element from the grid. This paper contains an overview of possibilities for using fuzzy logic in an assessment of primary faults in the transmission grid. The tool for this task is SCADA system, which is based on information of currents, voltages, events of protection devices and status of circuit breakers in the grid. The function model described with the membership function and fuzzy logic systems will be presented in the paper. For input data, diagnostics system uses information of protection devices tripping, states of circuit breakers and measurements of currents and voltages before and after faults.
High-voltage, high-power, solid-state remote power controllers for aerospace applications
NASA Technical Reports Server (NTRS)
Sturman, J. C.
1985-01-01
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.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-10-04
... Volatility) (i) To reflect changes to market-wide circuit breaker triggers for NMS stocks, and (ii) amend... trading in all OTC Equity Securities when a market-wide circuit breaker is in effect for NMS stocks. The... Equity Securities pursuant to its authority under Rule 6440(a)(3) \\3\\ until the market-wide circuit...
Compact self-powered synchronous energy extraction circuit design with enhanced performance
NASA Astrophysics Data System (ADS)
Liu, Weiqun; Zhao, Caiyou; Badel, Adrien; Formosa, Fabien; Zhu, Qiao; Hu, Guangdi
2018-04-01
Synchronous switching circuit is viewed as an effective solution of enhancing the generator’s performance and providing better adaptability for load variations. A critical issue for these synchronous switching circuits is the self-powered realization. In contrast with other methods, the electronic breaker possesses the advantage of simplicity and reliability. However, beside the energy consumption of the electronic breakers, the parasitic capacitance decreases the available piezoelectric voltage. In this technical note, a new compact design of the self-powered switching circuit using electronic breaker is proposed. The envelope diodes are excluded and only a single envelope capacitor is used. The parasitic capacitance is reduced to half with boosted performance while the components are reduced with cost saved.
46 CFR 111.54-3 - Remote control.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 46 Shipping 4 2012-10-01 2012-10-01 false Remote control. 111.54-3 Section 111.54-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Circuit Breakers § 111.54-3 Remote control. Remotely controlled circuit breakers must have local...
46 CFR 111.54-3 - Remote control.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 46 Shipping 4 2011-10-01 2011-10-01 false Remote control. 111.54-3 Section 111.54-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Circuit Breakers § 111.54-3 Remote control. Remotely controlled circuit breakers must have local...
46 CFR 111.54-3 - Remote control.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 46 Shipping 4 2014-10-01 2014-10-01 false Remote control. 111.54-3 Section 111.54-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Circuit Breakers § 111.54-3 Remote control. Remotely controlled circuit breakers must have local...
46 CFR 111.54-3 - Remote control.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 46 Shipping 4 2010-10-01 2010-10-01 false Remote control. 111.54-3 Section 111.54-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Circuit Breakers § 111.54-3 Remote control. Remotely controlled circuit breakers must have local...
46 CFR 111.54-3 - Remote control.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 46 Shipping 4 2013-10-01 2013-10-01 false Remote control. 111.54-3 Section 111.54-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Circuit Breakers § 111.54-3 Remote control. Remotely controlled circuit breakers must have local...
77 FR 16486 - Airworthiness Directives; Fokker Services B.V. Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2012-03-21
... values of nuts on circuit breakers, contactors and terminal blocks of the EPC and battery relay panel... battery relay panel]. The required actions include doing a general visual inspection to determine if... and circuit breakers, contactors, and terminal blocks of the EPC and battery relay panel, as...
Development of the Vacuum Circuit Breaker with an Electromagnetic Actuator
NASA Astrophysics Data System (ADS)
Morita, Ayumu; Yabu, Masato; Kajiwara, Satoru
A new type of vacuum circuit breaker (VCB) has been developed, which needs a minimum of maintenance. This VCB is characterized by the following: (a) a significantly simplified driving mechanism, (b) no need for grease, and (c) a new electromagnetic actuator called a hybrid-type electromagnet. The number of movable parts is decreased to 15% of that of our conventional product with a spring drive. Solid lubricant is adopted instead of grease for almost all of the linkages, which helps to eliminate periodical lubricating maintenance. The hybrid-type electromagnet has an attractive force suitable for the spring force characteristics of the VCB through its combination of conventional plunger-type and plate-armature-type electromagnet. The VCB is held in the closed position by the attractive force of the permanent magnet without using a coil current. Its core structure is optimized to prevent the permanent magnet from demagnetization and to secure long-term reliability. To assess the solid lubricant reliability, some special tests were performed such as a rare operation test. Dynamic characteristics were measured for three specimens at intervals of a month, a year, and two years, respectively. It was confirmed that variation of the armature speed is small and the influence of the non-operation interval is negligible.
Review of 72.5kV double-break vacuum circuit breaker based on rapid repulsion actuator
NASA Astrophysics Data System (ADS)
Zhuofan, Tang; Lijun, Qin
2017-07-01
72.5kV double-break vacuum circuit breakers based on rapid repulsion actuator remain blank in China. Based on the theoretical analysis and experimental results from researchers, the design of 72.5kV double-break vacuum circuit breakers based on rapid repulsion actuator was presented. It takes the form of double-break, using two standard 40.5kV vacuum interrupter in series at the bottom, which adopt a permanent magnetic repulsion actuator. The permanent magnetic repulsion actuator consists of rapid repulsion actuator and magnetic retentivity actuator. On the basis above, we produced the prototype, and the superiority of the design was verified through the experiments.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-04-11
... securities suddenly declining by significant amounts in a very short time period before suddenly reversing to... circuit breaker pilot program, which was implemented through a series of rule filings by the equity exchanges and by FINRA.\\9\\ The single-stock circuit breaker was designed to reduce extraordinary market...
78 FR 56601 - Airworthiness Directives; Fokker Services B.V. Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2013-09-13
... torque values of nuts on circuit breakers, contactors, and terminal blocks of the EPC and battery relay... blocks of the EPC and battery relay panel, as applicable; and do all applicable adjustments of the torque... contacts and nuts on circuit breakers, contactors, and terminal blocks of the EPC and battery relay panel...
The Implications of the Use of Parental Choice as a Legal "Circuit Breaker"
ERIC Educational Resources Information Center
Mead, Julie F.; Lewis, Maria M.
2016-01-01
This study explores four instances where parental choice has been employed as a legal "circuit breaker": (a) First Amendment Establishment Clause cases related to public funding, (b) Fourteenth Amendment Equal Protection cases regarding race-conscious student assignment, (c) Title IX regulations concerning single-sex education, and (d) a…
Federal Register 2010, 2011, 2012, 2013, 2014
2013-04-11
... by significant amounts in a very short time period before suddenly reversing to prices consistent... circuit breaker pilot program, which was implemented through a series of rule filings by the equity exchanges and by FINRA.\\6\\ The single-stock circuit breaker was designed to reduce extraordinary market...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-04-11
... securities suddenly declining by significant amounts in a very short time period before suddenly reversing to... circuit breaker pilot program, which was implemented through a series of rule filings by the equity exchanges and by FINRA.\\8\\ The single-stock circuit breaker was designed to reduce extraordinary market...
Remote control circuit breaker evaluation testing. [for space shuttles
NASA Technical Reports Server (NTRS)
Bemko, L. M.
1974-01-01
Engineering evaluation tests were performed on several models/types of remote control circuit breakers marketed in an attempt to gain some insight into their potential suitability for use on the space shuttle vehicle. Tests included the measurement of several electrical and operational performance parameters under laboratory ambient, space simulation, acceleration and vibration environmental conditions.
30 CFR 75.601-1 - Short circuit protection; ratings and settings of circuit breakers.
Code of Federal Regulations, 2011 CFR
2011-07-01
... (amperes) 14 50 12 75 10 150 8 200 6 300 4 500 3 600 2 800 1 1,000 1/0 1,250 2/0 1,500 3/0 2,000 4/0 2,500... of circuit breakers. 75.601-1 Section 75.601-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES...
NASA Astrophysics Data System (ADS)
Luxa, Andreas
The necessary conditions in switching system and vacuum circuit breaker for the occurrence of multiple re-ignitions and accompanying effects were examined. The shape of the occurring voltages was determined in relationship to other types of overvoltage. A phenomenological model of the arc, based on an extension of the Mayr equation for arcs was used with the simulation program NETOMAC for the switching transients. Factors which affect the arc parameters were analyzed. The results were statistically verified by 3000 three-phase switching tests on 3 standard vacuum circuit breakers under realistic systems conditions; the occurring overvoltage level was measured. Dimensioning criteria for motor simulation circuits in power plants were formulated on the basis of a theoretical equivalence analysis and experimental studies. The simulation model allows a sufficiently correct estimation of all effects.
Hydraulically-actuated operating system for an electric circuit breaker
Barkan, Philip; Imam, Imdad
1978-01-01
This hydraulically-actuated operating system comprises a cylinder, a piston movable therein in an opening direction to open a circuit breaker, and an accumulator for supplying pressurized liquid to a piston-actuating space within the cylinder. A normally-closed valve between the accumulator and the actuating space is openable to allow pressurized liquid from the accumulator to flow through the valve into the actuating space to drive the piston in an opening direction. A vent is located hydraulically between the actuating space and the valve for affording communication between said actuating space and a low pressure region. Flow control means is provided for restricting leakage through said vent to a rate that prevents said leakage from substantially detracting from the development of pressure within said actuatng space during the period from initial opening of the valve to the time when said piston has moved through most of its opening stroke. Following such period and while the valve is still open, said flow control means allows effective leakage through said vent. The accumulator has a limited capacity that results in the pressure within said actuating space decaying promptly to a low value as a result of effective leakage through said vent after the piston has moved through a circuit-breaker opening stroke and while the valve is in its open state. Means is provided for resetting the valve to its closed state in response to said pressure decay in the actuating space.
NASA Astrophysics Data System (ADS)
Lin, Xin; Wang, Feiming; Xu, Jianyuan; Xia, Yalong; Liu, Weidong
2016-03-01
According to the stream theory, this paper proposes a mathematical model of the dielectric recovery characteristic based on the two-temperature ionization equilibrium equation. Taking the dynamic variation of charged particle's ionization and attachment into account, this model can be used in collaboration with the Coulomb collision model, which gives the relationship of the heavy particle temperature and electron temperature to calculate the electron density and temperature under different pressure and electric field conditions, so as to deliver the breakdown electric field strength under different pressure conditions. Meanwhile an experiment loop of the circuit breaker has been built to measure the breakdown voltage. It is shown that calculated results are in conformity with experiment results on the whole while results based on the stream criterion are larger than experiment results. This indicates that the mathematical model proposed here is more accurate for calculating the dielectric recovery characteristic, it is derived from the stream model with some improvement and refinement and has great significance for increasing the simulation accuracy of circuit breaker's interruption characteristic. supported by Science and Technology Project of State Grid Corporation of China (No. GY17201200063), National Natural Science Foundation of China (No. 51277123), Basic Research Project of Liaoning Key Laboratory of Education Department (LZ2015055)
75 FR 22043 - Airworthiness Directives; Agusta S.p.A. (Agusta) Model A109E Helicopters
Federal Register 2010, 2011, 2012, 2013, 2014
2010-04-27
... report of an electrical failure, an investigation revealed inadequate functioning of the 35 amperes (Amps... to replace the 35 Amps with a 50 Amps circuit breaker and replace the wires with oversized ones to... of the 35 Amps BATT BUS circuit breaker. To prevent an electrical failure, the manufacturer has...
Moving characteristics of electrodes for vacuum circuit breaker
NASA Astrophysics Data System (ADS)
Yuan, Shun; Wang, Jimei
1994-05-01
This paper analyzes the effect of the gap of electrodes on the state of vacuum arc by experiment and theory. And the model of vacuum arc is set up. The optimal gap can be deduced from controlling the vacuum arc to be diffusion state, in order to get the optimal moving characteristics of electrodes.
ERIC Educational Resources Information Center
Netzer, Dick; Berne, Robert
1995-01-01
Ideally, voters' and state legislatures' policy choices should underlie a property tax system that is straightforward, comprehensible, systematic, and reasonably related to policy objectives. Administration should be uniform and fair. New York State's property tax system lacks a uniform valuation standard and "circuit breaker" and has…
Code of Federal Regulations, 2013 CFR
2013-10-01
... Offers for Air Circuit Breakers, as prescribed in 225.7006-4(a), to comply with 10 U.S.C. 2534(a)(3). (xxxvii) Use the clause at 252.225-7038, Restriction on Acquisition of Air Circuit Breakers, as prescribed...(c). (xlv) Use the clause at 252.232-7003, Electronic Submission of Payment Requests and Receiving...
Development of a 66kV Class Rectifier Type Fault Current Limiter System
NASA Astrophysics Data System (ADS)
Ohkuma, Takeshi; Sato, Yoshibumi; Takahashi, Yoshihisa; Tokuda, Noriaki; Murai, Masaki; Nagasaki, Norihisa; Yuguchi, Kyousuke
A fault current limiter (FCL) is extensively expected to suppress fault current, particularly required for trunk power systems heavily connected high-voltage transmission lines, such as 500 kV class power system which constitutes the nucleus of the electric power system. By installing such FCL in the power system, the system interconnection is possible without the need to raise the capacity of the circuit breakers, and it is expected that FCLs may be used in more efficient power system design. For these reasons, FCLs based on various principles of operation have been developed in the world. In this paper, we have proposed a new type of FCL system, consisting of solid-state diodes, DC coil and bypass AC coil, and described the specification of distribution power system and 66 kV class FCL model. Also we have proposed a 66 kV class prototype single-phase model and the current limiting performance of this model was evaluated using a short circuit generator.
Design of high-voltage, high-power, solid state remote power controllers for aerospace applications
NASA Technical Reports Server (NTRS)
Sturman, J. C.
1985-01-01
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.
Design of high-voltage, high-power, solid state remote power controllers for aerospace applications
NASA Astrophysics Data System (ADS)
Sturman, J. C.
1985-05-01
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.
NASA Astrophysics Data System (ADS)
Tsukima, Mitsuru; Takeuchi, Toshie; Koyama, Kenichi; Yoshiyasu, Hajimu
This paper presents a design and testing of a new high-speed electromagnetic driving mechanism for a high-voltage vacuum circuit breaker (VCB). This mechanism is based on a high-speed electromagnetic repulsion and a permanent magnet spring (PMS). This PMS is introduced instead of the conventional disk spring due to its low spring energy and more suitable force characteristics for VCB application. The PMS has been optimally designed by the 3d non-linear finite-elements magnetic field analysis and investigated its internal friction and eddy-current effect. Furthermore, we calculated the dynamic of this mechanism coupling with the electromagnetic field and circuit analysis, in order to satisfy the operating characteristics—contact velocity, response time and so on, required for the high-speed VCB. A prototype VCB, which was built based on the above analysis shows sufficient operating performance. Finally, the short circuit interruption tests were carried out with this prototype breaker, and we have been able to verify its satisfying performance.
Technical Trend of Environment-friendly High Voltage Vacuum Circuit Breaker (VCB)
NASA Astrophysics Data System (ADS)
Okubo, Hitoshi
Vacuum Circuit Breakers (VCBs) have widely been used for low and medium voltage level, because of their high current interruption performance, maintenance free operations and environment-friendly characteristics. The VCB is now going to be applied to higher voltage systems for transmission and substation use. In this paper, the recent technical trend and future perspectives of high voltage VCBs are described, as well as their technical background.
30 CFR 75.900-2 - Approved circuit schemes.
Code of Federal Regulations, 2011 CFR
2011-07-01
... device installed in the main secondary circuit at the source transformer may be used to provide undervoltage protection for each circuit that receives power from that transformer. (c) One circuit breaker may...
30 CFR 75.900-2 - Approved circuit schemes.
Code of Federal Regulations, 2014 CFR
2014-07-01
... device installed in the main secondary circuit at the source transformer may be used to provide undervoltage protection for each circuit that receives power from that transformer. (c) One circuit breaker may...
30 CFR 75.900-2 - Approved circuit schemes.
Code of Federal Regulations, 2013 CFR
2013-07-01
... device installed in the main secondary circuit at the source transformer may be used to provide undervoltage protection for each circuit that receives power from that transformer. (c) One circuit breaker may...
30 CFR 75.900-2 - Approved circuit schemes.
Code of Federal Regulations, 2012 CFR
2012-07-01
... device installed in the main secondary circuit at the source transformer may be used to provide undervoltage protection for each circuit that receives power from that transformer. (c) One circuit breaker may...
30 CFR 75.900-2 - Approved circuit schemes.
Code of Federal Regulations, 2010 CFR
2010-07-01
... device installed in the main secondary circuit at the source transformer may be used to provide undervoltage protection for each circuit that receives power from that transformer. (c) One circuit breaker may...
A No-Arc DC Circuit Breaker Based on Zero-Current Interruption
NASA Astrophysics Data System (ADS)
Xiang, Xuewei; Chai, Jianyun; Sun, Xudong
2017-05-01
A dc system has no natural current zero-crossing point, so a dc arc is more difficult to extinguish than an ac arc. In order to effectively solve the problem of the dc arc, this paper proposes a dc circuit breaker (DCCB) capable of implementing a no-arc interruption. The proposed DCCB includes a main branch consisting of a mechanical switch, a diode and a current-limiting inductor, a semi-period resonance circuit consisting of a diode, an inductor and a capacitor, and a buffer branch consisting of a capacitor, a thyristor and a resistor. The mechanical switch is opened in a zero-current state, and the overvoltage caused by the counter electromotive force of the inductor does not exist. Meanwhile, the capacitor has a buffering effect on the voltage. The rising of the voltage of the mechanical switch is slower than the rising of the insulating strength of a contact gap of the mechanical switch, resulting in the contact gap not able to be broken down. Thus, the arc cannot be generated. The simulation results show that the proposed DCCB does not generate the arc in the interruption process, the rise rate of the short circuit current can be effectively limited, and the short circuit fault point can be rapidly isolated from the dc power supply.
2003-08-27
KENNEDY SPACE CENTER, FLA. - During power-up of the orbiter Discovery in the Orbiter Processing Facility, a technician (left) looks at the circuit breaker lights in the cabin. Discovery has been undergoing Orbiter Major Modifications in the past year, ranging from wiring, control panels and black boxes to gaseous and fluid systems tubing and components. These systems were deserviced, disassembled, inspected, modified, reassembled, checked out and reserviced, as were most other systems onboard. The work includes the installation of the Multifunction Electronic Display Subsystem (MEDS) - a state-of-the-art “glass cockpit.”
30 CFR 77.900-2 - Testing, examination, and maintenance of circuit breakers; record.
Code of Federal Regulations, 2011 CFR
2011-07-01
... protecting low- and medium-voltage circuits serving three-phase alternating current equipment and such record... AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES Low- and Medium-Voltage Alternating Current Circuits...
30 CFR 75.900-3 - Testing, examination, and maintenance of circuit breakers; procedures.
Code of Federal Regulations, 2010 CFR
2010-07-01
... current circuits serving three-phase alternating current equipment and their auxiliary devices shall be... Underground Low- and Medium-Voltage Alternating Current Circuits § 75.900-3 Testing, examination, and...
30 CFR 77.900-1 - Testing, examination, and maintenance of circuit breakers; procedures.
Code of Federal Regulations, 2011 CFR
2011-07-01
... protecting low- and medium-voltage circuits serving portable or mobile three-phase alternating current... AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES Low- and Medium-Voltage Alternating Current Circuits...
30 CFR 77.900-2 - Testing, examination, and maintenance of circuit breakers; record.
Code of Federal Regulations, 2010 CFR
2010-07-01
... protecting low- and medium-voltage circuits serving three-phase alternating current equipment and such record... AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES Low- and Medium-Voltage Alternating Current Circuits...
30 CFR 77.900-1 - Testing, examination, and maintenance of circuit breakers; procedures.
Code of Federal Regulations, 2010 CFR
2010-07-01
... protecting low- and medium-voltage circuits serving portable or mobile three-phase alternating current... AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES Low- and Medium-Voltage Alternating Current Circuits...
30 CFR 75.900-3 - Testing, examination, and maintenance of circuit breakers; procedures.
Code of Federal Regulations, 2011 CFR
2011-07-01
... current circuits serving three-phase alternating current equipment and their auxiliary devices shall be... Underground Low- and Medium-Voltage Alternating Current Circuits § 75.900-3 Testing, examination, and...
Code of Federal Regulations, 2012 CFR
2012-07-01
... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Low- and medium-voltage circuits serving three... STANDARDS-UNDERGROUND COAL MINES Underground Low- and Medium-Voltage Alternating Current Circuits § 75.900 Low- and medium-voltage circuits serving three-phase alternating current equipment; circuit breakers...
Code of Federal Regulations, 2014 CFR
2014-07-01
... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Low- and medium-voltage circuits serving... Medium-Voltage Alternating Current Circuits § 77.900 Low- and medium-voltage circuits serving portable or mobile three-phase alternating current equipment; circuit breakers. Low- and medium-voltage circuits...
Code of Federal Regulations, 2014 CFR
2014-07-01
... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Low- and medium-voltage circuits serving three... STANDARDS-UNDERGROUND COAL MINES Underground Low- and Medium-Voltage Alternating Current Circuits § 75.900 Low- and medium-voltage circuits serving three-phase alternating current equipment; circuit breakers...
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Low- and medium-voltage circuits serving three... STANDARDS-UNDERGROUND COAL MINES Underground Low- and Medium-Voltage Alternating Current Circuits § 75.900 Low- and medium-voltage circuits serving three-phase alternating current equipment; circuit breakers...
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Low- and medium-voltage circuits serving... Medium-Voltage Alternating Current Circuits § 77.900 Low- and medium-voltage circuits serving portable or mobile three-phase alternating current equipment; circuit breakers. Low- and medium-voltage circuits...
Code of Federal Regulations, 2012 CFR
2012-07-01
... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Low- and medium-voltage circuits serving... Medium-Voltage Alternating Current Circuits § 77.900 Low- and medium-voltage circuits serving portable or mobile three-phase alternating current equipment; circuit breakers. Low- and medium-voltage circuits...
30 CFR 75.900-4 - Testing, examination, and maintenance of circuit breakers; record.
Code of Federal Regulations, 2011 CFR
2011-07-01
... circuits serving three-phase alternating current equipment used in the mine. Such record shall be kept in a... Underground Low- and Medium-Voltage Alternating Current Circuits § 75.900-4 Testing, examination, and...
30 CFR 75.900-4 - Testing, examination, and maintenance of circuit breakers; record.
Code of Federal Regulations, 2010 CFR
2010-07-01
... circuits serving three-phase alternating current equipment used in the mine. Such record shall be kept in a... Underground Low- and Medium-Voltage Alternating Current Circuits § 75.900-4 Testing, examination, and...
ERIC Educational Resources Information Center
Rice, Mike
2006-01-01
Circuit breakers are the linchpin of an institution's power-distribution system, so it's not surprising that several warning signs of an aging system relate to these devices. When warning signs occur, it's a message to facilities managers and administrators that breakers may need to be upgraded to help the power distribution system meet existing…
30 CFR 75.508 - Map of electrical system.
Code of Federal Regulations, 2010 CFR
2010-07-01
... apparatus in connection with the mine electric system, including permanent cables, switchgear, rectifying... direct-current circuit breakers protecting underground trolley circuits, shall be shown on a mine map...
30 CFR 75.508 - Map of electrical system.
Code of Federal Regulations, 2011 CFR
2011-07-01
... apparatus in connection with the mine electric system, including permanent cables, switchgear, rectifying... direct-current circuit breakers protecting underground trolley circuits, shall be shown on a mine map...
NASA Astrophysics Data System (ADS)
Harmanpreet, Singh, Sukhwinder; Kumar, Ashok; Kaur, Parneet
2010-11-01
Stability & security are main aspects in electrical power systems. Transformer protection is major issue of concern to system operation. There are many mall-trip cases of transformer protection are caused by inrush current problems. The phenomenon of transformer inrush current has been discussed in many papers since 1958. In this paper analytical analysis of inrush current in a transformer switched on dc and ac supply has been done. This analysis will help in design aspects of circuit breakers for better performance.
NASA Astrophysics Data System (ADS)
Brylina, O. G.; Semenova, K. D.; Shashkin, V. YU
2018-03-01
The article considers the issues of increasing the reliability and economy of the distribution substation. The result is found due to the reconstruction of the central distribution substation and one of the plants of Chelyabinsk region. The reasons for the reconstruction are explained. A comparison of oil and vacuum circuit breakers is made. The advantages of vacuum circuit breakers are shown. Alternative replacement of cables is offered. The basic technical characteristics of the cable brands are shown. The results of reconstruction are proved.
The Working of Circuit Breakers Within Percolation Models for Financial Markets
NASA Astrophysics Data System (ADS)
Ehrenstein, Gudrun; Westerhoff, Frank
We use a modified Cont-Bouchaud model to explore the effectiveness of trading breaks. The modifications include that the trading activity of the market participants depends positively on historical volatility and that the orders of the agents are conditioned on the observed mispricing. Trading breaks, also called circuit breakers, interrupt the trading process when prices are about to exceed a pre-specified limit. We find that trading breaks are a useful instrument to stabilize financial markets. In particular, trading breaks may reduce price volatility and deviations from fundamentals.
Optical diagnostics of the arc plasma using fast intensified CCD-spectrograph system
NASA Astrophysics Data System (ADS)
Pavelescu, Gabriela; Guillot, Stephane; Braic, Mariana T.; Hong, Dunpin; Pavelescu, D.; Fleurier, Claude; Braic, Viorel; Gherendi, F.; Dumitrescu, G.; Anghelita, P.; Bauchire, J. M.
2004-10-01
Spectroscopic diagnostics, using intensified high speed CCD camera, was applied to study the arc dynamics in low voltage circuit breakers, in vacuum and in air. Time-resolved emission spectroscopy of the vacuum arc plasma, generated during electrode separation, provided information about the interruption process. The investigations were focused on the partial unsuccessful interruption around current zero. Absorption spectroscopy, in a peculiar setup, was used in order to determine the metallic atoms densities in the interelectrode space of a low voltage circuit breaker, working in ambient air.
Investigation of DC hybrid circuit breaker based on high-speed switch and arc generator
NASA Astrophysics Data System (ADS)
Wu, Yifei; Rong, Mingzhe; Wu, Yi; Yang, Fei; Li, Mei; Zhong, Jianying; Han, Guohui; Niu, Chunping; Hu, Yang
2015-02-01
A new design of DC hybrid circuit breaker based on high-speed switch (HSS) and arc generator (AG), which can drastically profit from low heat loss in normal state and fast current breaking under fault state, is presented and analyzed in this paper. AG is designed according to the magnetic pinch effect of liquid metal. By utilizing the arc voltage generated across AG, the fault current is rapidly commutated from HSS into parallel connected branch. As a consequence, the arcless open of HSS is achieved. The post-arc conducting resume time (Δ tc) of AG and the commutation original voltage (Uc), two key factors in the commutation process, are investigated experimentally. Particularly, influences of the liquid metal channel diameter (Φ) of AG, fault current rate of rise (di/dt) and Uc on Δ tc are focused on. Furthermore, a suitable Uc is determined during the current commutation process, aiming at the reliable arcless open of HSS and short breaking time. Finally, the fault current breaking test is carried out for the current peak value of 11.8 kA, and the validity of the design is confirmed by the experimental results.
Investigation of DC hybrid circuit breaker based on high-speed switch and arc generator.
Wu, Yifei; Rong, Mingzhe; Wu, Yi; Yang, Fei; Li, Mei; Zhong, Jianying; Han, Guohui; Niu, Chunping; Hu, Yang
2015-02-01
A new design of DC hybrid circuit breaker based on high-speed switch (HSS) and arc generator (AG), which can drastically profit from low heat loss in normal state and fast current breaking under fault state, is presented and analyzed in this paper. AG is designed according to the magnetic pinch effect of liquid metal. By utilizing the arc voltage generated across AG, the fault current is rapidly commutated from HSS into parallel connected branch. As a consequence, the arcless open of HSS is achieved. The post-arc conducting resume time (Δ tc) of AG and the commutation original voltage (Uc), two key factors in the commutation process, are investigated experimentally. Particularly, influences of the liquid metal channel diameter (Φ) of AG, fault current rate of rise (di/dt) and Uc on Δ tc are focused on. Furthermore, a suitable Uc is determined during the current commutation process, aiming at the reliable arcless open of HSS and short breaking time. Finally, the fault current breaking test is carried out for the current peak value of 11.8 kA, and the validity of the design is confirmed by the experimental results.
NASA Technical Reports Server (NTRS)
Praver, Gerald A.; Theisinger, Peter C.; Genofsky, John
1987-01-01
Functions of circuit breakers, meters, and switches combined. Circuit that includes power field-effect transistors (PFET's) provides on/off switching, soft starting, current monitoring, current tripping, and protection against overcurrent for 30-Vdc power supply at normal load currents up to 2 A. Has no moving parts.
NASA Astrophysics Data System (ADS)
Jia, Shenli; Mo, Yongpeng; Shi, Zongqian; Li, Junliang; Wang, Lijun
2017-10-01
The post-arc dielectric recovery process has a decisive effect on the current interruption performance in a vacuum circuit breaker. The dissipation of residual plasma at the moment of current zero under the transient recovery voltage, which is the first stage of the post-arc dielectric recovery process and forms the post-arc current, has attracted many concerns. A one-dimensional particle-in-cell model is developed to simulate the measured post-arc current in the vacuum circuit breaker in this paper. At first, the parameters of the residual plasma are estimated roughly by the waveform of the post-arc current which is taken from measurements. After that, different components of the post-arc current, which are formed by the movement of charged particles in the residual plasma, are discussed. Then, the residual plasma density is adjusted according to the proportion of electrons and ions absorbed by the post-arc anode derived from the particle-in-cell simulation. After this adjustment, the post-arc current waveform obtained from the simulation is closer to that obtained from measurements.
NASA Astrophysics Data System (ADS)
Chen, Yi; Yang, Fei; Sun, Hao; Wu, Yi; Niu, Chunping; Rong, Mingzhe
2017-06-01
After current zero, which is the moment when the vacuum circuit breaker interrupts a vacuum arc, sheath development is the first process in the dielectric recovery process. An axial magnetic field (AMF) is widely used in the vacuum circuit breaker when the high-current vacuum arc is interrupted. Therefore, it is very important to study the influence of different AMF amplitudes on the sheath development. The objective of this paper is to study the influence of different AMF amplitudes on the sheath development from a micro perspective. Thus, the particle in cell-Monte Carlo collisions (PIC-MCC) method was adopted to develop the sheath development model. We compared the simulation results with the experimental results and then validated the simulation. We also obtained the speed of the sheath development and the energy density of the ions under different AMF amplitudes. The results showed that the larger the AMF amplitudes are, the faster the sheath develops and the lower the ion energy density is, meaning the breakdown is correspondingly more difficult.
46 CFR 28.365 - Overcurrent protection and switched circuits.
Code of Federal Regulations, 2011 CFR
2011-10-01
.... (c) Each ungrounded current carrying conductor must be protected in accordance with its current carrying capacity by a circuit breaker or fuse at the connection to the switchboard or distribution panel...
46 CFR 58.25-55 - Overcurrent protection for steering-gear systems.
Code of Federal Regulations, 2010 CFR
2010-10-01
... overcurrent protection except short-circuit protection that is instantaneous and rated at 400% to 500% of— (1... for steering-gear systems. (a) Each feeder circuit for steering must be protected by a circuit breaker... motor for an alternating-current motor. (b) No feeder circuit for steering may have any overcurrent...
The new technological solution for the JT-60SA quench protection circuits
NASA Astrophysics Data System (ADS)
Gaio, E.; Maistrello, A.; Novello, L.; Matsukawa, M.; Perna, M.; Ferro, A.; Yamauchi, K.; Piovan, R.
2018-07-01
An advanced technology has been developed and employed for the main circuit breakers (CB) of the quench protection circuits (QPC) of the superconducting coils of JT-60SA: it consists in a Hybrid mechanical-static CB (HCB) composed of a mechanical Bypass switch (BPS) for conducting the continuous current, in parallel to a static circuit breaker (SCB) based on integrated gate commutated thyristor (IGCT) for current interruption. It was the result of a R&D program carried out since 2006 to identify innovative solutions for the interruption of high dc current, able to improve the maintainability and availability of the CB. The HCB developed for the JT-60SA QPC is the first realization of a dc circuit breaker based on this design approach for interrupting current of some tens of kA with reapplied voltage of some kV. It also represents the first application of hybrid technology with IGCT for protection of superconducting magnets in fusion experiments. The paper aims at giving a comprehensive overview of the main R&D activities devoted to the development of this new technological approach; then, the key aspects of the design, manufacturing and testing of the QPCs for JT-60SA, successfully completed in Naka Site in summer 2015 are presented. Finally, the significance of this research is discussed and the possible future developments, in particular in view of DEMO fusion reactor, are outlined.
Innovation Incubator: Whisker Labs Technical Evaluation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sparn, Bethany F.; Frank, Stephen M.; Earle, Lieko
The Wells Fargo Innovation Incubator (IN2) is a program to foster and accelerate startup companies with commercial building energy-efficiency and demand management technologies. The program is funded by the Wells Fargo Foundation and co-administered by the National Renewable Energy Laboratory (NREL). Whisker Labs, an Oakland, California-based company, was one of four awardees in the first IN2 cohort and was invited to participate in the program because of its novel electrical power sensing technology for circuit breakers. The stick-on Whisker meters install directly on the front face of the circuit breakers in an electrical panel using adhesive, eliminating the need tomore » open the panel and install current transducers (CTs) on the circuit wiring.« less
Simulation of switching overvoltages in the mine electric power supply system
NASA Astrophysics Data System (ADS)
Ivanchenko, D. I.; Novozhilov, N. G.
2017-02-01
Overvoltages occur in mine power supply systems during switching off consumers with high inductive load, such as transformers, reactors and electrical machines. Overvoltages lead to an increase of insulation degradation rate and may cause electric faults, power outage, fire and explosion of methane and coal dust. This paper is dedicated to simulation of vacuum circuit breaker switching overvoltages in a mine power supply system by means of Simulink MATLAB. The model of the vacuum circuit breaker implements simulation of transient recovery voltage, current chopping and an electric arc. Obtained results were compared to available experimental data.
Simulation of the Process of Arc Energy-Effect in High Voltage Auto-Expansion SF6 Circuit Breaker
NASA Astrophysics Data System (ADS)
Rong, Mingzhe; Yang, Qian; Fan, Chunduo
2005-12-01
A new magnetic hydro-dynamics (MHD) model of arc in H.V. auto-expansion SF6 circuit breaker that takes into consideration nozzle ablation due to both radiation and thermal conduction is presented in this paper. The effect of PTFE (polytetrafluorethylene) vapor is considered in the mass, momentum and energy conservation equations of the constructed model. Then, the gas flow fields with and without conduction considered are simulated. By comparing the aforementioned two results, it is indicated that the arc's maximal temperature with conduction considered is 90 percent of that without considering conduction.
Synchronous Controlled Switching by VCB with Electromagnetic Operation Mechanism
NASA Astrophysics Data System (ADS)
Horinouchi, Katsuhiko; Tsukima, Mitsuru; Tohya, Nobumoto; Inoue, Ryuuichi; Sasao, Hiroyuki
Synchronously controlled switching to suppress transient overvoltage and overcurrent resulting from when the circuit breakers on medium voltage systems are closed is described. Firstly, by simulation it is found that if the closing time is synchronously controlled so that the contacts of the circuit breaker close completely at the instant when the voltage across contacts of the breaker at each of the three individual phases are zero, the resulting overvoltage and overcurrent is significantly suppressed when compared to conventional three phase simultaneous closing. Next, an algorithm for determining the closing timing based on a forecasted voltage zero waveform, obtained from voltage sampling data, is presented. Finally, a synchronous closing experiment of voltage 22kV utilizing a controller to implement the algorithm and a VCB with an electromagnetic operation mechanism is presented. The VCB was successfully closed at the zero point within a tolerance range of 200 microseconds.
46 CFR 120.380 - Overcurrent protection.
Code of Federal Regulations, 2010 CFR
2010-10-01
... for each ungrounded conductor for the purpose of opening the electric circuit if the current reaches a value that causes an excessive or dangerous temperature in the conductor or conductor insulation. (b) The grounded conductor of a circuit must not be disconnected by a switch or circuit breaker, unless...
46 CFR 120.380 - Overcurrent protection.
Code of Federal Regulations, 2011 CFR
2011-10-01
... for each ungrounded conductor for the purpose of opening the electric circuit if the current reaches a value that causes an excessive or dangerous temperature in the conductor or conductor insulation. (b) The grounded conductor of a circuit must not be disconnected by a switch or circuit breaker, unless...
14 CFR 25.1357 - Circuit protective devices.
Code of Federal Regulations, 2013 CFR
2013-01-01
... designed to de-energize and disconnect faulty power sources and power transmission equipment from their... malfunctioning. (c) Each resettable circuit protective device must be designed so that, when an overload or... must be designed so that circuit breakers are not the primary means to remove or reset system power...
14 CFR 25.1357 - Circuit protective devices.
Code of Federal Regulations, 2012 CFR
2012-01-01
... designed to de-energize and disconnect faulty power sources and power transmission equipment from their... malfunctioning. (c) Each resettable circuit protective device must be designed so that, when an overload or... must be designed so that circuit breakers are not the primary means to remove or reset system power...
14 CFR 25.1357 - Circuit protective devices.
Code of Federal Regulations, 2014 CFR
2014-01-01
... designed to de-energize and disconnect faulty power sources and power transmission equipment from their... malfunctioning. (c) Each resettable circuit protective device must be designed so that, when an overload or... must be designed so that circuit breakers are not the primary means to remove or reset system power...
14 CFR 25.1357 - Circuit protective devices.
Code of Federal Regulations, 2011 CFR
2011-01-01
... designed to de-energize and disconnect faulty power sources and power transmission equipment from their... malfunctioning. (c) Each resettable circuit protective device must be designed so that, when an overload or... must be designed so that circuit breakers are not the primary means to remove or reset system power...
Code of Federal Regulations, 2010 CFR
2010-01-01
... on electrical devices, including those on relays, interrupters, switches, contactors, terminal blocks and circuit breakers, and other circuit protection devices. (4) Connectors, including feed-through... connections. (7) Electrical splices. (8) Materials used to provide additional protection for wires, including...
Code of Federal Regulations, 2011 CFR
2011-01-01
... on electrical devices, including those on relays, interrupters, switches, contactors, terminal blocks and circuit breakers, and other circuit protection devices. (4) Connectors, including feed-through... connections. (7) Electrical splices. (8) Materials used to provide additional protection for wires, including...
DOE Office of Scientific and Technical Information (OSTI.GOV)
El Hariri, Mohamad; Faddel, Samy; Mohammed, Osama
Decentralized and hierarchical microgrid control strategies have lain the groundwork for shaping the future smart grid. Such control approaches require the cooperation between microgrid operators in control centers, intelligent microcontrollers, and remote terminal units via secure and reliable communication networks. In order to enhance the security and complement the work of network intrusion detection systems, this paper presents an artificially intelligent physical model-checking that detects tampered-with circuit breaker switching control commands whether, due to a cyber-attack or human error. In this technique, distributed agents, which are monitoring sectionalized areas of a given microgrid, will be trained and continuously adapted tomore » verify that incoming control commands do not violate the physical system operational standards and do not put the microgrid in an insecure state. The potential of this approach has been tested by deploying agents that monitor circuit breakers status commands on a 14-bus IEEE benchmark system. The results showed the accuracy of the proposed framework in characterizing the power system and successfully detecting malicious and/or erroneous control commands.« less
NASA Astrophysics Data System (ADS)
Wang, Weizong; Rong, Mingzhe; Wu, Yi; Yan, Joseph D.
2014-06-01
Sulfur hexafluoride (SF6) gas, used widely in high-voltage circuit breakers, can produce a remarkable greenhouse effect if released into the atmosphere. Fundamental properties of SF6 mixed with CO2 at high temperatures are presented in this paper, considering their reduction of adverse impact on the environment as a replacement for pure SF6 in high-voltage circuit breakers: to the knowledge of the authors, related data have not been reported in the literature. The species composition and thermodynamic properties (mass density, enthalpy and specific heat at constant pressure) are determined by the method of Gibbs free energy minimization, using standard thermodynamic tables. The transport properties, including viscosity, thermal conductivity and electrical conductivity, are evaluated by using the Chapman-Enskog method expanded up to the third-order approximation (second order for viscosity). Particular attention is paid to the establishment of a collision integral database related to a reacting species system containing basic elements of carbon, oxygen and sulfur as well as fluoride by the use of recent cross sections or interaction potentials available in the literature. The calculations, which assume a local thermodynamic equilibrium, are performed in the temperature range 300 to 30 000 K for different pressures between 0.01 and 1.6 MPa. The results obtained are compared to those of previously published studies, and the reasons for discrepancies are analysed. An evaluation of the current interruption performance by adding CO2 to SF6 is discussed from a microscopic point of view. The results provide reliable reference data for the simulation of switching arcs in high-voltage circuit breakers in SF6-CO2 mixtures.
Study of switching electric circuits with DC hybrid breaker, one stage
NASA Astrophysics Data System (ADS)
Niculescu, T.; Marcu, M.; Popescu, F. G.
2016-06-01
The paper presents a method of extinguishing the electric arc that occurs between the contacts of direct current breakers. The method consists of using an LC type extinguishing group to be optimally sized. From this point of view is presented a theoretical approach to the phenomena that occurs immediately after disconnecting the load and the specific diagrams are drawn. Using these, the elements extinguishing group we can choose. At the second part of the paper there is presented an analyses of the circuit switching process by decomposing the process in particular time sequences. For every time interval there was conceived a numerical simulation model in MATLAB-SIMULINK medium which integrates the characteristic differential equation and plots the capacitor voltage variation diagram and the circuit dumping current diagram.
Barkan, Philip; Imam, Imdad
1980-01-01
This circuit breaker comprises a plurality of a vacuum-type circuit interrupters, each having a movable contact rod. A common operating device for the interrupters comprises a linearly-movable operating member. The interrupters are mounted at one side of the operating member with their movable contact rods extending in a direction generally toward the operating member. Means is provided for mechanically coupling the operating member to the contact rods, and this means comprises a plurality of insulating operating rods, each connected at one end to the operating member and at its opposite end to one of the movable contact rods. The operating rods are of substantially equal length and have longitudinal axes that converge and intersect at substantially a common point.
NASA Astrophysics Data System (ADS)
Wu, Mingliang; Yang, Fei; Rong, Mingzhe; Wu, Yi; Qi, Yang; Cui, Yufei; Liu, Zirui; Guo, Anxiang
2016-04-01
This paper focuses on the numerical investigation of arc characteristics in an air direct current circuit breaker (air DCCB). Using magneto-hydrodynamics (MHD) theory, 3D laminar model and turbulence model are constructed and calculated. The standard k-epsilon model is utilized to consider the turbulence effect in the arc chamber of the DCCB. Several important phenomena are found: the arc column in the turbulence-model case is more extensive, moves much more slowly than the counterpart in the laminar-model case, and shows stagnation at the entrance of the chamber, unlike in the laminar-model case. Moreover, the arc voltage in the turbulence-model case is much lower than in the laminar-model case. However, the results in the turbulence-model case show a much better agreement with the results of the breaking experiments under DC condition than in the laminar-model case, which is contradictory to the previous conclusions from the arc researches of both the low-voltage circuit breaker and the sulfur hexafluoride (SF6) nozzle. First, in the previous air-arc research of the low-voltage circuit breaker, it is assumed that the air plasma inside the chamber is in the state of laminar, and the laminar-model application gives quite satisfactory results compared with the experiments, while in this paper, the laminar-model application works badly. Second, the turbulence-model application in the arc research of the SF6-nozzle performs much better and gives higher arc voltage than the laminar-model application does, whereas in this paper, the turbulence-model application predicts lower arc voltage than the laminar-model application does. Based on the analysis of simulation results in detail, the mechanism of the above phenomena is revealed. The transport coefficients are strongly changed by turbulence, which will enhance the arc diffusion and make the arc volume much larger. Consequently, the arc appearance and the distribution of Lorentz force in the turbulence-model case substantially differ from the arc appearance and the distribution of Lorentz force in the laminar-model case. Thus, the moving process of the arc in the turbulence-model case is slowed down and slower than in the laminar-model case. Moreover, the more extensive arc column in the turbulence-model case reduces the total arc resistance, which results in a lower arc voltage, more consistent with the experimental results than the arc voltage in the laminar-model case. Therefore, the air plasma inside this air DCCB is believed to be in the turbulence state, and the turbulence model is more suitable than the laminar model for the arc simulation of this kind of air DCCB.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wu, Mingliang; Yang, Fei, E-mail: yfei2007@mail.xjtu.edu.cn; Rong, Mingzhe
This paper focuses on the numerical investigation of arc characteristics in an air direct current circuit breaker (air DCCB). Using magneto-hydrodynamics (MHD) theory, 3D laminar model and turbulence model are constructed and calculated. The standard k-epsilon model is utilized to consider the turbulence effect in the arc chamber of the DCCB. Several important phenomena are found: the arc column in the turbulence-model case is more extensive, moves much more slowly than the counterpart in the laminar-model case, and shows stagnation at the entrance of the chamber, unlike in the laminar-model case. Moreover, the arc voltage in the turbulence-model case ismore » much lower than in the laminar-model case. However, the results in the turbulence-model case show a much better agreement with the results of the breaking experiments under DC condition than in the laminar-model case, which is contradictory to the previous conclusions from the arc researches of both the low-voltage circuit breaker and the sulfur hexafluoride (SF6) nozzle. First, in the previous air-arc research of the low-voltage circuit breaker, it is assumed that the air plasma inside the chamber is in the state of laminar, and the laminar-model application gives quite satisfactory results compared with the experiments, while in this paper, the laminar-model application works badly. Second, the turbulence-model application in the arc research of the SF6-nozzle performs much better and gives higher arc voltage than the laminar-model application does, whereas in this paper, the turbulence-model application predicts lower arc voltage than the laminar-model application does. Based on the analysis of simulation results in detail, the mechanism of the above phenomena is revealed. The transport coefficients are strongly changed by turbulence, which will enhance the arc diffusion and make the arc volume much larger. Consequently, the arc appearance and the distribution of Lorentz force in the turbulence-model case substantially differ from the arc appearance and the distribution of Lorentz force in the laminar-model case. Thus, the moving process of the arc in the turbulence-model case is slowed down and slower than in the laminar-model case. Moreover, the more extensive arc column in the turbulence-model case reduces the total arc resistance, which results in a lower arc voltage, more consistent with the experimental results than the arc voltage in the laminar-model case. Therefore, the air plasma inside this air DCCB is believed to be in the turbulence state, and the turbulence model is more suitable than the laminar model for the arc simulation of this kind of air DCCB.« less
Kramer, Axel; Over, Daniel; Stoller, Patrick; Paul, Thomas A
2017-05-20
Novel dielectric insulation gases used as alternatives to sulfur hexafluoride in gas-insulated switchgear (GIS) include several mixtures containing fluorinated organic compounds. We developed a fiber-optic analyzer enabling concentration measurement of fluoroketones used in medium- and high-voltage switchgear applications by ABB, with concurrent compensation of disturbing effects caused by dust and dirt. The sensor enables measurements in GIS and even in operating high-voltage circuit breakers. The online availability of concentration readings of fluoroketones is important for development tests, but can also be applied for monitoring or diagnostics of field installations.
NASA Astrophysics Data System (ADS)
Cheng, Shaoyong; Xiu, Shixin; Wang, Jimei; Shen, Zhengchao
2006-11-01
The greenhouse effect of SF6 is a great concern today. The development of high voltage vacuum circuit breakers becomes more important. The vacuum circuit breaker has minimum pollution to the environment. The vacuum interrupter is the key part of a vacuum circuit breaker. The interrupting characteristics in vacuum and arc-controlling technique are the main problems to be solved for a longer gap distance in developing high voltage vacuum interrupters. To understand the vacuum arc characteristics and provide effective technique to control vacuum arc in a long gap distance, the arc mode transition of a cup-type axial magnetic field electrode is observed by a high-speed charge coupled device (CCD) video camera under different gap distances while the arc voltage and arc current are recorded. The controlling ability of the axial magnetic field on vacuum arc obviously decreases when the gap distance is longer than 40 mm. The noise components and mean value of the arc voltage significantly increase. The effective method for controlling the vacuum arc characteristics is provided by long gap distances based on the test results. The test results can be used as a reference to develop high voltage and large capacity vacuum interrupters.
76 FR 10215 - Airworthiness Directives; Learjet Inc. Model 45 Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2011-02-24
... above. This AD requires a general visual inspection for damage of wiring (including chafing, pinched... the pilot and copilot circuit breaker panels caused by a short circuit between chafed wiring and the... misrouted wires, which could result in a short circuit and the loss of systems associated with the wiring...
30 CFR 75.800-2 - Approved circuit schemes.
Code of Federal Regulations, 2010 CFR
2010-07-01
... necessary protection to the circuits required by § 75.800: (a) Ground check relays may be used for undervoltage protection if the relay coils are designed to trip the circuit breaker when line voltage decreases to 40 percent to 60 percent of the nominal line voltage; (b) Ground trip relays on resistance...
30 CFR 75.800-2 - Approved circuit schemes.
Code of Federal Regulations, 2011 CFR
2011-07-01
... necessary protection to the circuits required by § 75.800: (a) Ground check relays may be used for undervoltage protection if the relay coils are designed to trip the circuit breaker when line voltage decreases to 40 percent to 60 percent of the nominal line voltage; (b) Ground trip relays on resistance...
Driver circuit for solid state light sources
Palmer, Fred; Denvir, Kerry; Allen, Steven
2016-02-16
A driver circuit for a light source including one or more solid state light sources, a luminaire including the same, and a method of so driving the solid state light sources are provided. The driver circuit includes a rectifier circuit that receives an alternating current (AC) input voltage and provides a rectified AC voltage. The driver circuit also includes a switching converter circuit coupled to the light source. The switching converter circuit provides a direct current (DC) output to the light source in response to the rectified AC voltage. The driver circuit also includes a mixing circuit, coupled to the light source, to switch current through at least one solid state light source of the light source in response to each of a plurality of consecutive half-waves of the rectified AC voltage.
BETA (Bitter Electromagnet Testing Apparatus)
NASA Astrophysics Data System (ADS)
Bates, Evan M.; Birmingham, William J.; Rivera, William F.; Romero-Talamas, Carlos A.
2017-10-01
The Bitter Electromagnet Testing Apparatus (BETA) is a 1-Tesla (T) prototype of the 10-T Adjustable Long Pulse High-Field Apparatus (ALPHA). These water-cooled resistive magnets use high DC currents to produce strong uniform magnetic fields. Presented here is the successful completion of the BETA project and experimental results validating analytical magnet designing methods developed at the Dusty Plasma Laboratory (DPL). BETA's final design specifications will be highlighted which include electromagnetic, thermal and stress analyses. The magnet core design will be explained which include: Bitter Arcs, helix starters, and clamping annuli. The final version of the magnet's vessel and cooling system are also presented, as well as the electrical system of BETA, which is composed of a unique solid-state breaker circuit. Experimental results presented will show the operation of BETA at 1 T. The results are compared to both analytical design methods and finite element analysis calculations. We also explore the steady state maximums and theoretical limits of BETA's design. The completion of BETA validates the design and manufacturing techniques that will be used in the succeeding magnet, ALPHA.
Stoffels, M; Simon, S; Nikolic, P G; Stoller, P; Carstensen, J
2017-03-01
High-voltage gas circuit breakers, which play an important role in the operation and protection of the power grid, function by drawing an arc between two contacts and then extinguishing it by cooling it using a transonic gas flow. Improving the design of circuit breakers requires an understanding of the physical processes in the interruption of the arc, particularly during the zero crossing of the alternating current (the point in time when the arc can be interrupted). Most diagnostic techniques currently available focus on measurement of current, voltage, and gas pressure at defined locations. However, these integral properties do not give sufficient insight into the arc physics. To understand the current interruption process, spatially resolved information about the density, temperature, and conductivity of the arc and surrounding gas flow is needed. Owing to the three-dimensional, unstable nature of the arc in a circuit breaker, especially near current zero, a spatially resolved, tomographic diagnostic technique is required that is capable of freezing the rapid, transient behavior and that is insensitive to the vibrations and electromagnetic interference inherent in the interruption of short-circuit current arcs. Here a new measurement system, based on background-oriented schlieren (BOS) imaging, is presented and assessed. BOS imaging using four beams consisting of white light sources, a background pattern, imaging optics, and a camera permits measurement of the line-of-sight integrated refractive index. Tomographic reconstruction is used to determine the three-dimensional, spatially resolved index of refraction distribution that in turn is used to calculate the density. The quantitative accuracy of a single beam of the BOS setup is verified by using a calibration lens with a known focal length. The ability of the tomographic reconstruction to detect asymmetric features of the arc and surrounding gas flow is assessed semiquantitatively using a nozzle that generates two gas jets, as described in [Exp. Fluids43, 241 (2007)EXFLDU0723-486410.1007/s00348-007-0331-1]. Experiments using a simple model of a circuit breaker, which provides optical access to an ∼1 kA arc that burns between two contacts and is blown through a nozzle system by synthetic air from a high pressure reservoir, are also described. The density in the decaying arc and surrounding gas flow is reconstructed, and the limitations of the technique, which are related to the temporal and spatial resolution, are addressed.
Cathode surface effects and H.F.-behaviour of vacuum arcs
NASA Astrophysics Data System (ADS)
Fu, Yan Hong
To gain a better understanding of the essential processes occurring during a vacuum arc interruption for the further development of the vacuum arc circuit breaker, cathode spot behavior, current interruption, dielectrical recovery and overvoltage generation are investigated. An experimental study on cathode spot behavior of the DC vacuum arc in relation to cathode surface roughness and a qualitative physical model to interpret the results are reported. An experimental investigation on the High Frequency (HF) current interruption, multiple recognitions and voltage escalation phenomena is reported. A calculation program to predict the level of overvoltages generated by the operation of a vacuum breaker in a realistic single phase circuit is developed. Detailed results are summarized.
Code of Federal Regulations, 2012 CFR
2012-07-01
..., assembles, or fabricates, or controls the design, manufacture, assembly, or fabrication of a fuse, and who... means a device, no less effective than an automatic circuit breaker, for use with direct current which... MINING PRODUCTS FUSES FOR USE WITH DIRECT CURRENT IN PROVIDING SHORT-CIRCUIT PROTECTION FOR TRAILING...
Code of Federal Regulations, 2013 CFR
2013-07-01
..., assembles, or fabricates, or controls the design, manufacture, assembly, or fabrication of a fuse, and who... means a device, no less effective than an automatic circuit breaker, for use with direct current which... MINING PRODUCTS FUSES FOR USE WITH DIRECT CURRENT IN PROVIDING SHORT-CIRCUIT PROTECTION FOR TRAILING...
Code of Federal Regulations, 2014 CFR
2014-07-01
..., assembles, or fabricates, or controls the design, manufacture, assembly, or fabrication of a fuse, and who... means a device, no less effective than an automatic circuit breaker, for use with direct current which... MINING PRODUCTS FUSES FOR USE WITH DIRECT CURRENT IN PROVIDING SHORT-CIRCUIT PROTECTION FOR TRAILING...
NASA Astrophysics Data System (ADS)
Liu, Chang; Lv, Xiangyu; Guo, Li; Cai, Lixia; Jie, Jinxing; Su, Kuo
2017-05-01
With the increasing of penetration of distributed in the smart grid, the problems that the power loss increasing and short circuit capacity beyond the rated capicity of circuit breaker will become more serious. In this paper, a methodology (Modified BPSO) is presented for network reconfiguration which is based on hybrid approach of Tabu Search and BPSO algorithms to prevent the local convergence and to decrease the calculation time using double fitnesses to consider the constraints. Moreover, an average load simulated method (ALS method) load variation considered is proposed that the average load value is used to instead of the actual load to calculation. Finally, from a case study, the results of simulation certify the approaches will decrease drastically the losses and improve the voltage profiles obviously, at the same time, the short circuit capacity is also decreased into less the shut-off capacity of circuit breaker. The power losses won’t be increased too much even if the short circuit capacity constraint is considered; voltage profiles are better with the constraint of short circuit capacity considering. The ALS method is simple and calculated time is speed.
A New Method for Raising Opening Velocity of Electromagnetic Actuated Vacuum Circuit Breaker
NASA Astrophysics Data System (ADS)
Tsukima, Mitsuru; Takeuchi, Toshie; Koyama, Kenichi; Yoshiyasu, Hajimu
Recently an electromagnetic actuator has been widely used as an operating mechanism for the vacuum circuit breaker (VCB). The opening velocity of the contact is supposed to be strongly related with current interruption performance. This paper presents a simple and new technique that raises opening velocity of the electromagnetic actuated VCB. In order to investigate this reason, we built a numerical simulator that predicts the dynamic characteristics of the VCB contact. It takes into account of the magnetic behavior in the actuator and is also coupled with the external control circuit. According to this simulation, it is shown that it is originated from the sharp rise in the electromagnetic thrust force due to the selective saturation of the magnetic yoke. As the result of our experiments, by this technique the opening velocity was verified to be 1.5 times faster than by the conventional way.
NASA Technical Reports Server (NTRS)
1972-01-01
Guidelines for the design, development, and fabrication of electronic components and circuits for use in spacecraft construction are presented. The subjects discussed involve quality control procedures and test methodology for the following subjects: (1) monolithic integrated circuits, (2) hybrid integrated circuits, (3) transistors, (4) diodes, (5) tantalum capacitors, (6) electromechanical relays, (7) switches and circuit breakers, and (8) electronic packaging.
33 CFR 183.460 - Overcurrent protection: Special applications.
Code of Federal Regulations, 2011 CFR
2011-07-01
... Requirements § 183.460 Overcurrent protection: Special applications. (a) Each ungrounded output conductor from... conductor is in the main power feed circuit from the battery to an engine cranking motor. The circuit breaker or fuse must be within 72 inches of the battery measured along the conductor, unless, for boats...
33 CFR 183.455 - Overcurrent protection: General.
Code of Federal Regulations, 2011 CFR
2011-07-01
....455 Overcurrent protection: General. (a) Each ungrounded current-carrying conductor must be protected... breaker or fuse must be placed at the source of power for each circuit or conductor except: (1) If it is... seven inches of the source of power for each circuit or conductor measured along the conductor. (2) If...
33 CFR 183.460 - Overcurrent protection: Special applications.
Code of Federal Regulations, 2010 CFR
2010-07-01
... Requirements § 183.460 Overcurrent protection: Special applications. (a) Each ungrounded output conductor from... conductor is in the main power feed circuit from the battery to an engine cranking motor. The circuit breaker or fuse must be within 72 inches of the battery measured along the conductor, unless, for boats...
33 CFR 183.455 - Overcurrent protection: General.
Code of Federal Regulations, 2010 CFR
2010-07-01
....455 Overcurrent protection: General. (a) Each ungrounded current-carrying conductor must be protected... breaker or fuse must be placed at the source of power for each circuit or conductor except: (1) If it is... seven inches of the source of power for each circuit or conductor measured along the conductor. (2) If...
Computer Power: Part 1: Distribution of Power (and Communications).
ERIC Educational Resources Information Center
Price, Bennett J.
1988-01-01
Discussion of the distribution of power to personal computers and computer terminals addresses options such as extension cords, perimeter raceways, and interior raceways. Sidebars explain: (1) the National Electrical Code; (2) volts, amps, and watts; (3) transformers, circuit breakers, and circuits; and (4) power vs. data wiring. (MES)
46 CFR 169.667 - Switchboards.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 46 Shipping 7 2011-10-01 2011-10-01 false Switchboards. 169.667 Section 169.667 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Machinery and... circuit must have at the point of attachment to the power source either— (1) A Circuit breaker; or (2) A...
46 CFR 169.667 - Switchboards.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 46 Shipping 7 2012-10-01 2012-10-01 false Switchboards. 169.667 Section 169.667 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Machinery and... circuit must have at the point of attachment to the power source either— (1) A Circuit breaker; or (2) A...
46 CFR 169.667 - Switchboards.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 46 Shipping 7 2010-10-01 2010-10-01 false Switchboards. 169.667 Section 169.667 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Machinery and... circuit must have at the point of attachment to the power source either— (1) A Circuit breaker; or (2) A...
46 CFR 169.667 - Switchboards.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 46 Shipping 7 2013-10-01 2013-10-01 false Switchboards. 169.667 Section 169.667 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Machinery and... circuit must have at the point of attachment to the power source either— (1) A Circuit breaker; or (2) A...
75 FR 12793 - Petitions for Modification
Federal Register 2010, 2011, 2012, 2013, 2014
2010-03-17
... number'' on the subject line, by any of the following methods: 1. Electronic Mail: Standards-Petitions... cables will be no smaller than 10 American Wire Gauge (AWG); (4) all circuit breakers used to protect... unit calibrated to trip at 70% of phase to phase short circuit current. The trip setting of these...
29 CFR 1926.403 - General requirements.
Code of Federal Regulations, 2011 CFR
2011-07-01
... protect other equipment, the adequacy of the protection thus provided. (iii) Electrical insulation. (iv... switchboards, control panels, switches, circuit breakers, motor controllers, relays, and similar equipment...
DC Interruption Characteristic on Vacuum Circuit Breaker
NASA Astrophysics Data System (ADS)
Odaka, Hiromi; Yamada, Masataka; Sakuma, Ryohei; Ding, Cuie; Kaneko, Eiji; Yanabu, Satoru
A high speed vacuum circuit breaker (HSVCB) has been investigated. HSVCB makes high frequency current superimposed on a fault current so that the current is forced to be zero and is interrupted. Its interruption performance is considered to be dependent on a rate of change of the current (di/dt). As a fundamental research, we investigated the di/dt-dv/dt characteristics and the insulation recovery characteristic after interrupting the counter-pulse current for various contact materials of AgWC, CuW, and CuCr. The results revealed that the case where gap length is larger is better in a current interruption performance. Moreover, it was found that di/dt is not dependent on the insulation recovery characteristics, but the magnitude of interruption current influences greatly.
Electricity Submetering on the Cheap: Stick-on Electricity Meters
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lanzisera, Steven; Lorek, Michael; Pister, Kristofer
2014-08-17
We demonstrate a low-cost, 21 x 12 mm prototype Stick-on Electricity Meter (SEM) to replace traditional in-circuit-breaker-panel current and voltage sensors for building submetering. A SEM sensor is installed on the external face of a circuit breaker to generate voltage and current signals. This allows for the computation of real and apparent power as well as capturing harmonics created by non-linear loads. The prototype sensor is built using commercially available components, resulting in a production cost of under $10 per SEM. With no highvoltage install work requiring an electrician, home owners or other individuals can install the system in amore » few minutes with no safety implications. This leads to an installed system cost that is much lower than traditional submetering technology.. Measurement results from lab characterization as well as a real-world residential dwelling installation are presented, verifying the operation of our proposed SEM sensor. The SEM sensor can resolve breaker power levels below 10W, and it can be used to provide data for non-intrusive load monitoring systems at full sample rate.« less
NASA Astrophysics Data System (ADS)
Liu, Mengqi; Liu, Haijun; Wang, Zhikai
2017-01-01
Traditional LCL grid-tied converters haven't the ability to limit the short-circuit fault current and only remove grid-connected converter using the breaker. However, the VSC converters become uncontrollable after the short circuit fault cutting off and the power switches may be damaged if the circuit breaker removes slowly. Compared to the filter function of the LCL passive components in traditional VSC converters, the novel LCL-VSC converter has the ability of limiting the short circuit fault current using the reasonable designed LCL parameters. In this paper the mathematical model of the LCL converter is established and the characteristics of the short circuit fault current generated by the ac side and dc side are analyzed. Thus one design and optimization scheme of the reasonable LCL passive parameter is proposed for the LCL-VSC converter having short circuit fault current limiting ability. In addition to ensuring the LCL passive components filtering the high-frequency harmonic, this scheme also considers the impedance characteristics to limit the fault current of AC and DC short circuit fault respectively flowing through the power switch no more than the maximum allowable operating current, in order to make the LCL converter working continuously. Finally, the 200kW simulation system is set up to prove the validity and feasibility of the theoretical analysis using the proposed design and optimization scheme.
Electrical safety for high voltage arrays
NASA Technical Reports Server (NTRS)
Marshall, N. A.
1983-01-01
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.
A High Power Density Power System Electronics for NASA's Lunar Reconnaissance Orbiter
NASA Technical Reports Server (NTRS)
Hernandez-Pellerano, A.; Stone, R.; Travis, J.; Kercheval, B.; Alkire, G.; Ter-Minassian, V.
2009-01-01
A high power density, modular and state-of-the-art Power System Electronics (PSE) has been developed for the Lunar Reconnaissance Orbiter (LRO) mission. This paper addresses the hardware architecture and performance, the power handling capabilities, and the fabrication technology. The PSE was developed by NASA s Goddard Space Flight Center (GSFC) and is the central location for power handling and distribution of the LRO spacecraft. The PSE packaging design manages and distributes 2200W of solar array input power in a volume less than a cubic foot. The PSE architecture incorporates reliable standard internal and external communication buses, solid state circuit breakers and LiIon battery charge management. Although a single string design, the PSE achieves high reliability by elegantly implementing functional redundancy and internal fault detection and correction. The PSE has been environmentally tested and delivered to the LRO spacecraft for the flight Integration and Test. This modular design is scheduled to flight in early 2009 on board the LRO and Lunar Crater Observation and Sensing Satellite (LCROSS) spacecrafts and is the baseline architecture for future NASA missions such as Global Precipitation Measurement (GPM) and Magnetospheric MultiScale (MMS).
Development of 72kV High Pressure Air-insulated GIS with Vacuum Circuit Breaker
NASA Astrophysics Data System (ADS)
Rokunohe, Toshiaki; Yagihashi, Yoshitaka; Endo, Fumihiro; Aoyagi, Kenji; Saitoh, Hitoshi; Oomori, Takashi
SF6 gas has excellent dielectric strength and interruption performance. For these reasons, it has been widely used for gas insulated switchgear (GIS). However, use of SF6 gas has become regulated under agreements set at the 1997 COP3. So investigation and development for GIS with a lower amount of SF6 gas are being carried out worldwide. Presently, SF6 gas-free GIS has been commercialized for the 24kV class. Air or N2 gas is used as insulation gas for this GIS. On the other hand, SF6 gas-free GIS has not been commercialized for 72kV class GIS. Dielectric strengths of air and N2 gas are approximately 1/3 that of SF6 gas. So to enhance insulation performance of air and N2, we have investigated a hybrid gas insulation system which has the combined features of providing an insulation coating and suitable insulation gas. We have developed the world's first 72kV SF6 gas-free GIS. This paper deals with key technologies for SF6 gas-free GIS such as the hybrid insulation structure, bellows for the high pressure vacuum circuit breaker, a newly designed disconnector and spacer and prevention of particle levitation. Test results of 72kV high pressure air-insulated GIS with the vacuum circuit breaker are described.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sarrailh, P.; LAPLACE, CNRS, F-31062 Toulouse; Schneider Electric, Centre de Recherche 38 TEC, 38050 Grenoble Cedex 09
2009-09-01
During the postarc dielectric recovery phase in a vacuum circuit breaker, a cathode sheath forms and expels the plasma from the electrode gap. The success or failure of current breaking depends on how efficiently the plasma is expelled from the electrode gap. The sheath expansion in the postarc phase can be compared to sheath expansion in plasma immersion ion implantation except that collisions between charged particles and atoms generated by electrode evaporation may become important in a vacuum circuit breaker. In this paper, we show that electrode evaporation plays a significant role in the dynamics of the sheath expansion inmore » this context not only because charged particle transport is no longer collisionless but also because the neutral flow due to evaporation and temperature gradients may push the plasma toward one of the electrodes. Using a hybrid model of the nonequilibrium postarc plasma and cathode sheath coupled with a direct simulation Monte Carlo method to describe collisions between heavy species, we present a parametric study of the sheath and plasma dynamics and of the time needed for the sheath to expel the plasma from the gap for different values of plasma density and electrode temperatures at the beginning of the postarc phase. This work constitutes a preliminary step toward understanding and quantifying the risk of current breaking failure of a vacuum arc.« less
NASA Astrophysics Data System (ADS)
Sarrailh, P.; Garrigues, L.; Hagelaar, G. J. M.; Boeuf, J. P.; Sandolache, G.; Rowe, S.
2009-09-01
During the postarc dielectric recovery phase in a vacuum circuit breaker, a cathode sheath forms and expels the plasma from the electrode gap. The success or failure of current breaking depends on how efficiently the plasma is expelled from the electrode gap. The sheath expansion in the postarc phase can be compared to sheath expansion in plasma immersion ion implantation except that collisions between charged particles and atoms generated by electrode evaporation may become important in a vacuum circuit breaker. In this paper, we show that electrode evaporation plays a significant role in the dynamics of the sheath expansion in this context not only because charged particle transport is no longer collisionless but also because the neutral flow due to evaporation and temperature gradients may push the plasma toward one of the electrodes. Using a hybrid model of the nonequilibrium postarc plasma and cathode sheath coupled with a direct simulation Monte Carlo method to describe collisions between heavy species, we present a parametric study of the sheath and plasma dynamics and of the time needed for the sheath to expel the plasma from the gap for different values of plasma density and electrode temperatures at the beginning of the postarc phase. This work constitutes a preliminary step toward understanding and quantifying the risk of current breaking failure of a vacuum arc.
Code of Federal Regulations, 2013 CFR
2013-07-01
... substations, circuit breakers, other switchgear, gas-insulated lines, or power transformers. Fluorinated GHG... transformers containing a fluorinated GHG prior to sale or distribution, or offer for sale or distribution in...
Code of Federal Regulations, 2011 CFR
2011-07-01
... substations, circuit breakers, other switchgear, gas-insulated lines, or power transformers. Fluorinated GHG... transformers containing a fluorinated GHG prior to sale or distribution, or offer for sale or distribution in...
Code of Federal Regulations, 2012 CFR
2012-07-01
... substations, circuit breakers, other switchgear, gas-insulated lines, or power transformers. Fluorinated GHG... transformers containing a fluorinated GHG prior to sale or distribution, or offer for sale or distribution in...
A Practical Study of the 66kV Fault Current Limiter (FCL) System with Rectifier
NASA Astrophysics Data System (ADS)
Tokuda, Noriaki; Matsubara, Yoshio; Yuguchi, Kyosuke; Ohkuma, Takeshi; Hobara, Natsuro; Takahashi, Yoshihisa
A fault current limiter (FCL) is extensively expected to suppress fault current, particularly required for trunk power systems heavily connected high-voltage transmission lines, such as 500kV class power system which constitutes the nucleus of the electric power system. By installing such FCL in the power system, the system interconnection is possible without the need to raise the capacity of the circuit breakers, and facilities can be configured for efficiency, among other benefits. For these reasons, fault current limiters based on various principles of operation have been developed both in Japan and abroad. In this paper, we have proposed a new type of FCL system, consisting of solid-state diodes, DC coil and bypass AC coil, and described the specification of distribution power system and 66kV model at the island power system and the superconducting cable power system. Also we have made a practical study of 66kV class, which is the testing items and the future subjects of the rectifier type FCL system.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-01-28
... assemblies; oil/fuel filters; air/oil separation equipment; air filters/elements; catalytic converters... assemblies; AC line filters; dielectric items of paper/plastic; capacitors; circuit breakers; switching...
46 CFR 111.30-29 - Emergency switchboards.
Code of Federal Regulations, 2013 CFR
2013-10-01
... but not in the same space as a battery emergency power source. (d) Each alternating-current emergency... switchboard with a draw out or plug-in type generator circuit breaker that disconnects: (i) Each generator...
46 CFR 111.30-29 - Emergency switchboards.
Code of Federal Regulations, 2014 CFR
2014-10-01
... but not in the same space as a battery emergency power source. (d) Each alternating-current emergency... switchboard with a draw out or plug-in type generator circuit breaker that disconnects: (i) Each generator...
NASA Astrophysics Data System (ADS)
Khan, Umer Amir; Lee, Jong-Geon; Seo, In-Jin; Amir, Faisal; Lee, Bang-Wook
2015-11-01
Voltage source converter-based HVDC systems (VSC-HVDC) are a better alternative than conventional thyristor-based HVDC systems, especially for developing multi-terminal HVDC systems (MTDC). However, one of the key obstacles in developing MTDC is the absence of an adequate protection system that can quickly detect faults, locate the faulty line and trip the HVDC circuit breakers (DCCBs) to interrupt the DC fault current. In this paper, a novel hybrid-type superconducting circuit breaker (SDCCB) is proposed and feasibility analyses of its application in MTDC are presented. The SDCCB has a superconducting fault current limiter (SFCL) located in the main current path to limit fault currents until the final trip signal is received. After the trip signal the IGBT located in the main line commutates the current into a parallel line where DC current is forced to zero by the combination of IGBTs and surge arresters. Fault simulations for three-, four- and five-terminal MTDC were performed and SDCCB performance was evaluated in these MTDC. Passive current limitation by SFCL caused a significant reduction of fault current interruption stress in the SDCCB. It was observed that the DC current could change direction in MTDC after a fault and the SDCCB was modified to break the DC current in both the forward and reverse directions. The simulation results suggest that the proposed SDCCB could successfully suppress the DC fault current, cause a timely interruption, and isolate the faulty HVDC line in MTDC.
Soft switching circuit to improve efficiency of all solid-state Marx modulator for DBDs
NASA Astrophysics Data System (ADS)
Liqing, TONG; Kefu, LIU; Yonggang, WANG
2018-02-01
For an all solid-state Marx modulator applied in dielectric barrier discharges (DBDs), hard switching results in a very low efficiency. In this paper, a series resonant soft switching circuit, which series an inductance with DBD capacitor, is proposed to reduce the power loss. The power loss of the all circuit status with hard switching was analyzed, and the maximum power loss occurred during discharging at the rising and falling edges. The power loss of the series resonant soft switching circuit was also presented. A comparative analysis of the two circuits determined that the soft switching circuit greatly reduced power loss. The experimental results also demonstrated that the soft switching circuit improved the power transmission efficiency of an all solid-state Marx modulator for DBDs by up to 3 times.
77 FR 27144 - Airworthiness Directives; Agusta S.p.A. Helicopters
Federal Register 2010, 2011, 2012, 2013, 2014
2012-05-09
... that resulted from ``inadequate functioning of the 35 amperes (amps) BATT BUS circuit breaker.'' The.... (b) Unsafe Condition This AD defines the unsafe condition as failure of the 35 ampere (amp) ``BATT...
ONR Far East Scientific Bulletin. Volume 7. Number 1, January-March 1982.
1982-03-01
Engineering - Professor K. Tamaru Associate Professor H. Matsunami - Electronic Circuit Engineering - Professor F. Ikegami Associate Professor S...circuit breakers, ozonizers and production of ozone in silent discharges, and superconducting equipment. In addition, a very brief report is given of a...treatment plants (Mitsubishi Electric ozonizer work is discussed later in this paper), - electric fans including ventilating systems for long highway
75 FR 61341 - Airworthiness Directives; Agusta S.p.A. (Agusta) Model A109E Helicopters
Federal Register 2010, 2011, 2012, 2013, 2014
2010-10-05
... electrical failure, an investigation revealed inadequate functioning of the 35 amperes (Amps) battery bus... investigation revealed inadequate functioning of the 35 amperes (Amps) battery bus (BATT BUS) circuit breaker...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-07-01
... subject firm. The workers are engaged in activities related to the production of hydraulic magnetic... shift in production of hydraulic magnetic circuit breakers to Aguascalientes, Mexico. The amended notice...
Transient stability enhancement of electric power generating systems by 120-degree phase rotation
Cresap, Richard L.; Taylor, Carson W.; Kreipe, Michael J.
1982-01-01
A method and system for enhancing the transient stability of an intertied three-phase electric power generating system. A set of power exporting generators (10) is connected to a set of power importing generators (20). When a transient cannot be controlled by conventional stability controls, and imminent loss of synchronism is detected (such as when the equivalent rotor angle difference between the two generator sets exceeds a predetermined value, such as 150 degrees), the intertie is disconnected by circuit breakers. Then a switch (30) having a 120-degree phase rotation, or a circuit breaker having a 120-degree phase rotation is placed in the intertie. The intertie is then reconnected. This results in a 120-degree reduction in the equivalent rotor angle difference between the two generator sets, making the system more stable and allowing more time for the conventional controls to stabilize the transient.
Thomson scattering diagnostics of decay processes of Ar/SF6 gas-blast arcs confined by a nozzle
NASA Astrophysics Data System (ADS)
Tomita, Kentaro; Gojima, Daisuke; Nagai, Kazuhiko; Uchino, Kiichiro; Kamimae, Ryo; Tanaka, Yasunori; Suzuki, Katsumi; Iijima, Takanori; Uchii, Toshiyuki; Shinkai, Takeshi
2013-09-01
Because of its instability, it is difficult to measure precisely the electron density (ne) of a long-gap decaying arc discharge in a circuit breaker. However, it is well known that it is an essential parameter for the determination of success or failure of the current interruption in a circuit breaker. In this paper, the spatiotemporal evolutions of the electron density were successfully measured in decaying SF6 gas-blast arc discharges formed with a long gap (50 mm) in a confined nozzle using laser Thomson scattering. Pure Ar gas and an 80%Ar/20%SF6 mixture gas were used as the arc quenching media at atmospheric pressure. After reducing the current to zero, both the measured ne and arc radius in the Ar/SF6 gas arc clearly decayed more rapidly than in the pure Ar gas arc.
NASA Technical Reports Server (NTRS)
Brush, A. S.; Phillips, R. L.
1991-01-01
NASA Lewis Research Center and associated contractors have conducted a program to assess the potential requirements for a high-current switch to conceptually design a switch using the best existing technology, and to build and demonstrate a breadboard which meets the requirements. The result is the high current remote bus isolator (HRBI). The HRBI is rated at 180 V dc, 335 A continuous with a 1200 A interrupt rating. It also incorporates remote-control and protective features called for by the Space Station Freedom PMAD dc test bed design. Two breadboard 335 A circuit breakers were built and tested that demonstrate a promising concept of paralleled current-limiting modules. The units incorporated all control and protective features required by advanced aerospace power systems. Component stresses in each unit were determined by design, and are consistent with a life of many thousands of fault operations.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Olama, Mohammed M; Allgood, Glenn O; Kuruganti, Phani Teja
Electric utilities have a main responsibility to protect the lives and safety of their workers when they are working on low-, medium-, and high-voltage power lines and distribution circuits. With the anticipated widespread deployment of smart grids, a secure and highly reliable means of maintaining isolation of customer-owned distributed generation (DG) from the affected distribution circuits during maintenance is necessary to provide a fully de-energized work area, ensure utility personnel safety, and prevent hazards that can lead to accidents such as accidental electrocution from unanticipated power sources. Some circuits are serviced while energized (live line work) while others are de-energizedmore » for maintenance. For servicing de-energized circuits and equipment, lock-out tag-out (LOTO) programs provide a verifiable procedure for ensuring that circuit breakers are locked in the off state and tagged to indicate that status to operational personnel so that the lines will be checked for voltage to verify they are de-energized. The de-energized area is isolated from any energized sources, which traditionally are the substations. This procedure works well when all power sources and their interconnections are known armed with this knowledge, utility personnel can determine the appropriate circuits to de-energize for isolating the target line or equipment. However, with customer-owned DG tied into the grid, the risk of inadvertently reenergizing a circuit increases because circuit connections may not be adequately documented and are not under the direct control of the local utility. Thus, the active device may not be properly de-energized or isolated from the work area. Further, a remote means of de-energizing and locking out energized devices provides an opportunity for greatly reduced safety risk to utility personnel compared to manual operations. In this paper, we present a remotely controllable LOTO system that allows individual workers to determine the configuration and status of electrical system circuits and permit them to lock out customer-owned DG devices for safety purposes using a highly secure and ultra-reliable radio signal. The system consists of: (1) individual personal lockout devices, (2) lockout communications and logic module at circuit breakers, which are located at all DG devices, and (3) a database and configuration control process located at the utility operations center. The lockout system is a close permissive, i.e., loss of control power or communications will cause the circuit breaker to open. Once the DG device is tripped open, a visual means will provide confirmation of a loss of voltage and current that verifies the disconnected status of the DG. Further the utility personnel will be able to place their own lock electronically on the system to ensure a lockout functionally. The proposed LOTO system provides enhanced worker safety and protection against unintended energized lines when DG is present. The main approaches and challenges encountered through designing the proposed region-wide LOTO system are discussed in this paper. These approaches include: (1) evaluating the reliability of the proposed approach under N-modular redundancy with voter/spares configurations and (2) conducting a system level risk assessment study using the failure modes and effects analysis (FMEA) technique to identify and rank failure modes by probability of occurrence, probability of detection, and severity of consequences. This ranking allows a cost benefits analysis to be conducted such that dollars and efforts will be applied to the failures that provide greatest incremental gains in system capability (resilience, survivability, security, reliability, availability, etc.) per dollar spent whether capital, operations, or investment. Several simulation scenarios and their results are presented to demonstrate the viability of these approaches.« less
Nuclear pulse. I - Awakening to the chaos factor
NASA Astrophysics Data System (ADS)
Broad, W. J.
1981-05-01
The discovery of the significance of the high-voltage wave termed electromagnetic pulse (EMP), which occurs following the high-altitude detonation of a nuclear device, is discussed. The disruptions to the street lights, burglar alarms and circuit breakers of Hawaii caused by the detonation of a nuclear device 248 mi above Johnson Island in the Pacific in July, 1962 are described and attributed to the Compton electrons produced by the impact of gamma rays from the nuclear explosion on air in the upper atmosphere. It is pointed out, however, that at the time of the explosion, most communications systems were based on vacuum tube and electromechanical technology, which is about 10,000,000 times harder against EMP than integrated solid-state circuitry, and thus the threat posed by EMP to the power grid and communications capabilities was not apparent. Efforts undertaken to harden discrete (missile) and communications systems against EMP are outlined for the example of the Safeguard ABM system, and difficulties are pointed out. Soviet awareness of EMP is considered, and the discovery of vacuum tubes on board the state-of-the-art Foxbat MiG interceptor flown into Japan is noted as a possible indicator of this awareness. It is concluded that the problem of EMP will increase in significance as semiconductor electronics proliferates.
NASA Astrophysics Data System (ADS)
Shioiri, Tetsu; Asari, Naoki; Sato, Junichi; Sasage, Kosuke; Yokokura, Kunio; Homma, Mitsutaka; Suzuki, Katsumi
To investigate the reliability of equipment of vacuum insulation, a study was carried out to clarify breakdown probability distributions in vacuum gap. Further, a double-break vacuum circuit breaker was investigated for breakdown probability distribution. The test results show that the breakdown probability distribution of the vacuum gap can be represented by a Weibull distribution using a location parameter, which shows the voltage that permits a zero breakdown probability. The location parameter obtained from Weibull plot depends on electrode area. The shape parameter obtained from Weibull plot of vacuum gap was 10∼14, and is constant irrespective non-uniform field factor. The breakdown probability distribution after no-load switching can be represented by Weibull distribution using a location parameter. The shape parameter after no-load switching was 6∼8.5, and is constant, irrespective of gap length. This indicates that the scatter of breakdown voltage was increased by no-load switching. If the vacuum circuit breaker uses a double break, breakdown probability at low voltage becomes lower than single-break probability. Although potential distribution is a concern in the double-break vacuum cuicuit breaker, its insulation reliability is better than that of the single-break vacuum interrupter even if the bias of the vacuum interrupter's sharing voltage is taken into account.
NASA Astrophysics Data System (ADS)
Mo, Yongpeng; Shi, Zongqian; Bai, Zhibin; Jia, Shenli; Wang, Lijun
2016-05-01
The residual plasma in the inter-contact region of a vacuum circuit breaker moves towards the post-arc cathode at current zero, because the residual plasma mainly comes from the cathode spots during the arc burning process. In the most previous theoretical researches on the post-arc sheath expansion process of vacuum circuit breakers, only the thermal motion of residual plasma was taken into consideration. Alternately, the residual plasma was even assumed to be static at the moment of current zero in some simplified models. However, the influence of residual plasma drift velocity at current zero on the post-arc sheath expansion process was rarely investigated. In this paper, this effect is investigated by a one-dimensional particle-in-cell model. Simulation results indicate that the sheath expands slower with higher residual plasma drift velocity in the initial sheath expansion stage. However, with the increase of residual plasma drift velocity, the overall plasma density in the inter-contact region decreases faster, and the sheath expansion velocity increases earlier. Consequently, as a whole, it needs shorter time to expel the residual plasma from the inter-contact region. Furthermore, if the residual plasma drift velocity is high enough, the sheath expansion process ceases before it develops to the post-arc anode. Besides, the influence of the collisions between charges and neutrals is investigated as well in terms of the density of metal vapor. It shows that the residual plasma drift velocity takes remarkable effect only if the density of the metal vapor is relatively low, which corresponds to the circumstance of low-current interruptions.
The Combat-System/Ship-System Interface,
1982-02-01
sequence initiated by removal of the load shed signal. Re-eneAgize capabitiLty. Provide remotely controlled reclosable power control devices to...signal from the electrical plant control equipment. The power controllers would replace existing circuit breakers and incorporate reclose capability
Relation between plastic surface microtexturation and Ag film percolation and resistivity
NASA Astrophysics Data System (ADS)
Rapeaux, Michel; Tribut, Laurent
2017-09-01
Reinforced polycarbonate samples are textured by laser to get hydrophilic or hydrophobic surface. Then, Ag films are deposited on textured and non-textured samples by magnetron sputtering. In-situ resistivity measurement has been done to determine the electrical percolation threshold according to the texturation. Results are discussed and texturation is presented as one option to improve surface insulation in circuit breaker after a short-circuit event.
2010-08-31
circuit breakers for testing and analysis in ONR laboratories. Task 1.2 Contributors: Sunny Kedia, Shinzo Onishi , Scott Samson, Drew Hanser Task 1.2...HEAT SINK FOR HIGH-POWER MEMS SWITCH APPLICATIONS (TASK 1.3) Contributors: Priscila Spagnol, Shinzo Onishi , Drew Hanser, Weidong Wang, Sunny Kedia
30 CFR 75.800-4 - Testing, examination, and maintenance of circuit breakers; record.
Code of Federal Regulations, 2011 CFR
2011-07-01
... mine. (b) Record security. These records shall be made in a secure book that is not susceptible to alteration or electronically in a computer system so as to be secure and not susceptible to alteration. (c...
30 CFR 75.800-4 - Testing, examination, and maintenance of circuit breakers; record.
Code of Federal Regulations, 2012 CFR
2012-07-01
... mine. (b) Record security. These records shall be made in a secure book that is not susceptible to alteration or electronically in a computer system so as to be secure and not susceptible to alteration. (c...
30 CFR 75.800-4 - Testing, examination, and maintenance of circuit breakers; record.
Code of Federal Regulations, 2014 CFR
2014-07-01
... mine. (b) Record security. These records shall be made in a secure book that is not susceptible to alteration or electronically in a computer system so as to be secure and not susceptible to alteration. (c...
30 CFR 75.800-4 - Testing, examination, and maintenance of circuit breakers; record.
Code of Federal Regulations, 2013 CFR
2013-07-01
... mine. (b) Record security. These records shall be made in a secure book that is not susceptible to alteration or electronically in a computer system so as to be secure and not susceptible to alteration. (c...
SF6-alternative gases for application in gas-insulated switchgear
NASA Astrophysics Data System (ADS)
Li, Xingwen; Zhao, Hu; Murphy, Anthony B.
2018-04-01
The environmental problems caused by greenhouse gases have received unprecedented attention. Sulfur hexafluoride (SF6), which is the preferred gas for use in gas-insulated switchgear (circuit breakers, disconnect switches, etc. for high-voltage electrical circuits), has a very high global warming potential, and there is a large international effort to find alternative gases. Recently, this effort has made important progress, with promising alternative gases being identified and tested. An overview, in particular the current state of the art, of the study of SF6-alternative gases is presented in the paper. The review focuses on the application of the SF6-alternative gases in gas-insulated switchgear, with detailed analysis of calculations and measurements of their basic physical properties, dielectric strengths, and arc-quenching capabilities. Finally, a discussion of and perspectives on current research and future research directions are presented.
Numerical modeling of high-voltage circuit breaker arcs and their interraction with the power system
NASA Astrophysics Data System (ADS)
Orama, Lionel R.
In this work the interaction between series connected gas and vacuum circuit breaker arcs has been studied. The breakdown phenomena in vacuum interrupters during the post arc current period have been of special interest. Numerical models of gas and vacuum arcs were developed in the form of black box models. Especially, the vacuum post arc model was implemented by combining the existing transition model with an ion density function and expressions for the breakdown mechanisms. The test series studied reflect that for electric fields on the order of 10sp7V/m over the anode, the breakdown of the vacuum gap can result from a combination of both thermal and electrical stresses. For a particular vacuum device, the vacuum model helps to find the interruption limits of the electric field and power density over the anode. The series connection of gas and vacuum interrupters always performs better than the single gas device. Moreover, to take advantage of the good characteristics of both devices, the time between the current zero crossing in each interrupter can be changed. This current zero synchronization is controlled by changing the capacitance in parallel to the gas device. This gas/vacuum interrupter is suitable for interruption of very stressful short circuits in which the product of the dI/dt before current zero and the dV/dt after current zero is very high. Also, a single SF6 interrupter can be replaced by an air circuit breaker of the same voltage rating in series with a vacuum device without compromising the good performance of the SF6 device. Conceptually, a series connected vacuum device can be used for high voltage applications with equal distribution of electrical stresses between the individual interrupters. The equalization can be made by a sequential opening of the individual contact pairs, beginning with the interruptors that are closer to ground potential. This could eliminate the use of grading capacitors.
Merritt, Bernard T.; Dreifuerst, Gary R.
1994-01-01
A solid state switch, with reverse conducting thyristors, is designed to operate at 20 kV hold-off voltage, 1500 A peak, 1.0 .mu.s pulsewidth, and 4500 pps, to replace thyratrons. The solid state switch is more reliable, more economical, and more easily repaired. The switch includes a stack of circuit card assemblies, a magnetic assist and a trigger chassis. Each circuit card assembly contains a reverse conducting thyristor, a resistor capacitor network, and triggering circuitry.
Adaptive protection algorithm and system
Hedrick, Paul [Pittsburgh, PA; Toms, Helen L [Irwin, PA; Miller, Roger M [Mars, PA
2009-04-28
An adaptive protection algorithm and system for protecting electrical distribution systems traces the flow of power through a distribution system, assigns a value (or rank) to each circuit breaker in the system and then determines the appropriate trip set points based on the assigned rank.
Solar Power Satellite (SPS) solid-state antenna power combiner
NASA Technical Reports Server (NTRS)
1980-01-01
A low loss power-combining microstrip antenna suitable for solid state solar power satellite (SPS) application was developed. A unique approach for performing both the combining and radiating function in a single cavity-type circuit was verified, representing substantial refinements over previous demonstration models in terms of detailed geometry to obtain good matching and adequate bandwidth at the design frequency. The combiner circuit was designed, built, and tested and the overall results support the view that the solid state power-combining antenna approach is a viable candidate for a solid state SPS antenna building block.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mo, Yongpeng; Shi, Zongqian; Jia, Shenli
The residual plasma in the inter-contact region of a vacuum circuit breaker moves towards the post-arc cathode at current zero, because the residual plasma mainly comes from the cathode spots during the arc burning process. In the most previous theoretical researches on the post-arc sheath expansion process of vacuum circuit breakers, only the thermal motion of residual plasma was taken into consideration. Alternately, the residual plasma was even assumed to be static at the moment of current zero in some simplified models. However, the influence of residual plasma drift velocity at current zero on the post-arc sheath expansion process wasmore » rarely investigated. In this paper, this effect is investigated by a one-dimensional particle-in-cell model. Simulation results indicate that the sheath expands slower with higher residual plasma drift velocity in the initial sheath expansion stage. However, with the increase of residual plasma drift velocity, the overall plasma density in the inter-contact region decreases faster, and the sheath expansion velocity increases earlier. Consequently, as a whole, it needs shorter time to expel the residual plasma from the inter-contact region. Furthermore, if the residual plasma drift velocity is high enough, the sheath expansion process ceases before it develops to the post-arc anode. Besides, the influence of the collisions between charges and neutrals is investigated as well in terms of the density of metal vapor. It shows that the residual plasma drift velocity takes remarkable effect only if the density of the metal vapor is relatively low, which corresponds to the circumstance of low-current interruptions.« less
Rankin, R.A.; Kotter, D.K.
1997-05-13
The Hall-Effect Arc Protector is used to protect sensitive electronics from high energy arcs. The apparatus detects arcs by monitoring an electrical conductor, of the instrument, for changes in the electromagnetic field surrounding the conductor which would be indicative of a possible arcing condition. When the magnitude of the monitored electromagnetic field exceeds a predetermined threshold, the potential for an instrument damaging are exists and the control system logic activates a high speed circuit breaker. The activation of the breaker shunts the energy imparted to the input signal through a dummy load to the ground. After the arc condition is terminated, the normal signal path is restored. 2 figs.
Rankin, Richard A.; Kotter, Dale K.
1997-01-01
The Hall-Effect Arc Protector is used to protect sensitive electronics from high energy arcs. The apparatus detects arcs by monitoring an electrical conductor, of the instrument, for changes in the electromagnetic field surrounding the conductor which would be indicative of a possible arcing condition. When the magnitude of the monitored electromagnetic field exceeds a predetermined threshold, the potential for an instrument damaging are exists and the control system logic activates a high speed circuit breaker. The activation of the breaker shunts the energy imparted to the input signal through a dummy load to the ground. After the arc condition is terminated, the normal signal path is restored.
Zeng, Shengke; Powers, John R; Newbraugh, Bradley H
2010-06-01
Construction workers suffer the most electrocutions among all industries. Currently, there are no electrical contact warning devices on the market to protect workers. This paper proposes a worker-worn electric-field sensor. As the worker is in proximity to, or in contact with, a live power-circuit, the sensor sets off an audible/visual warning alarm. The sensor also has the potential to wirelessly trip a wireless-capable circuit breaker, and to trigger a wireless transmitter to notify emergency response of an electrical contact. An experiment was conducted to measure electric-field variation on simulated human-wrists (10 defrosted hog-legs) in various proximities and in electrical-contact to a simulated power-circuit. The purpose of these tests was to determine the feasibility of developing a worker-worn electric-field detection sensor for use in protecting workers from contact with energized electrical conductors. This study observed a significant electric-field-magnitude increase as a hog-leg approaches the live-circuit, and the distinct electric-field-magnitude jump as the leg contacts with the live-circuit. The observation indicates that this sensor can be an effective device to warn the workers of electrical hazards. Additionally, the sensor has the potential to wirelessly trip a wireless-capable circuit-breaker and trigger a wireless transmitter (such as a cell phone) to notify an emergency response. The prompt notification prevents the worker from further injury caused by postponed medical-care. Widespread use of this sensor could lower electrocution and electrically related injury rates in the construction industry. (c) 2010 Elsevier Ltd. All rights reserved.
Merritt, B.T.; Dreifuerst, G.R.
1994-07-19
A solid state switch, with reverse conducting thyristors, is designed to operate at 20 kV hold-off voltage, 1,500 A peak, 1.0 [mu]s pulsewidth, and 4,500 pps, to replace thyratrons. The solid state switch is more reliable, more economical, and more easily repaired. The switch includes a stack of circuit card assemblies, a magnetic assist and a trigger chassis. Each circuit card assembly contains a reverse conducting thyristor, a resistor capacitor network, and triggering circuitry. 6 figs.
NASA Astrophysics Data System (ADS)
Goeritno, Arief; Rasiman, Syofyan
2017-06-01
Performance examination of the bulk oil circuit breaker that is influenced by its parameters at the Substation of Bogor Baru (the State Electricity Company = PLN) has been done. It is found that (1) dielectric strength of oil still qualifies as an insulating and cooling medium, because the average value of the measurement result is still above the minimum value allowed, where the minimum limit of 80 kV/2.5 cm or 32 kV/cm; (2) the simultaneity of the CB's contacts is still eligible, so that the BOCB can still be operated, because the difference of time between the highest and lowest values when the BOCB's contacts are opened/closed are less than (Δt<) 10 milliseconds (if meeting the PLN standards as recommended by Alsthom); and (3) the parameter of resistance according to the standards, where (i) the resistance of insulation has a value far above the allowed threshold, while the minimum standards are above 2,000 Mn (if meeting the ANSI standards) or on the value of 2,000 MΩ (if meeting PLN standards), (ii) the resistance of contacts has a value far above the allowed threshold, while the minimum standards are below 350 µΩ (if meeting ANSI standards) or on the value of 200 µΩ (if meeting PLN standards). The resistance of grounding is equal to the maximum limit specified, while the maximum standard is on the value of 0.5 Ω (if meeting PLN standard).
Cleaning High-Voltage Equipment With Corncob Grit
NASA Technical Reports Server (NTRS)
Caveness, C.
1986-01-01
High electrical resistance of particles makes power shutdown unnecessary. New, inexpensive method of cleaning high-voltage electrical equipment uses plentiful agricultural product - corncob grit. Method removes dirt and debris from transformers, circuit breakers, and similar equipment. Suitable for utilities, large utility customers, and electrical-maintenance services.
Code of Federal Regulations, 2012 CFR
2012-10-01
... Acquisition of Air Circuit Breakers (JUN 2005) (10 U.S.C. 2534(a)(3)). (18) __ 252.225-7039, Contractors...)). (10 U.S.C. 2321). (23) __ 252.232-7003, Electronic Submission of Payment Requests and Receiving...
Code of Federal Regulations, 2011 CFR
2011-10-01
... Pub. L. 111-383). (17) __ 252.225-7038, Restriction on Acquisition of Air Circuit Breakers (JUN 2005...-7003, Electronic Submission of Payment Requests and Receiving Reports (MAR 2008) (10 U.S.C. 2227). (23...
Development of Electromagnetically Actuated Vacuum Circuit Breaker for 72kV Rated Switchgear
NASA Astrophysics Data System (ADS)
Kim, Tae-Hyun; Tsukima, Mitsuru; Maruyama, Akihiko; Takahara, Osamu; Haruna, Kazushi; Yano, Tomotaka; Matsunaga, Toshihiro; Imamura, Kazuaki; Arioka, Masahiro; Takeuchi, Toshie
A new electromagnetically actuated vacuum circuit breaker (VCB) has been developed for a 72kV rated switchgear. Each phase of this VCB has a plurality of compact electromagnetic actuators linked mechanically providing the required driving energy. The mechanical linkage working as a lever magnifies an actuator stroke to the required stroke of a 72kV rated vacuum interrupter. An electromagnetic analysis coupled with motion, which considers the mechanical linkage of the plural actuators, has been developed for designing the driving behavior of this VCB. Using this analytical method and a quality engineering method known as the Taguchi method, we have clarified effective parameters to reduce the time difference of the driving behavior for tolerance specifications. Moreover, analyzing the oscillatory behavior closing the contacts, a structure of this VCB has been designed to reduce the bounce duration. The developed new VCB has been confirmed that a time difference is short enough and bounce duration is reduced. This VCB is highly reliable against variations in manufacturing and environment.
NASA Astrophysics Data System (ADS)
Niwa, Yoshimitsu; Kaneko, Eiji
Vacuum circuit breakers (VCB) have been widely used for power distribution systems. Vacuum Interrupters, which are the current interruption unit, have been increased its interruption capability with the development of vacuum arc control technology by magnetic field. There are three major type electrodes: disk shaped electrodes, radial magnetic field electrodes, axial magnetic field (AMF) electrodes. In the disk shaped electrode, the vacuum arc between the electrodes is not controlled. In the AMF electrode, the vacuum arc is diffused and stabilized by an axial magnetic field, which is parallel to the arc current. In the last type of electrodes, the vacuum arc column is rotated by magnetic force generated by the current flowing in the electrodes. The interruption current and the voltage of one break VCB is increased to 100 kA, 144 kV respectively. This paper describes basic configurations and functions of VCB, vacuum arc control technology in vacuum interrupters, recent researches and applications of VCB.
Investigation of the dielectric recovery in synthetic air in a high voltage circuit breaker
NASA Astrophysics Data System (ADS)
Seeger, M.; Naidis, G.; Steffens, A.; Nordborg, H.; Claessens, M.
2005-06-01
The dielectric recovery of an axially blown arc in an experimental set-up based on a conventional HV circuit breaker was investigated both experimentally and theoretically. As a quenching gas, synthetic air was used. The investigated time range was from 10 µs to 10 ms after current zero (CZ). A fast rise in the dielectric strength during the first 100 µs, followed by a plateau and further rise later was observed. The dependences on the breaking current and pressure were determined. The measured dielectric recovery during the first 100 µs after CZ could be reproduced with good accuracy by computational fluid dynamics simulations. From that it could be deduced that the temperature decay in the axis does not depend sensitively on the pressure. The dielectric recovery during the first 100 µs scales therefore mainly with the filling pressure. The plateau in the breakdown characteristic is due to a hot vapour layer from the still evaporating PTFE nozzle surface.
NASA Astrophysics Data System (ADS)
Zhang, Junmin; Chen, Zhang
2008-10-01
A new magnetic hydro-dynamics model for nozzle arc emphasizing the interaction of arc with PTFE (polytetrafluorethylene) vapour is established based on the conservation equations. The interruption of auto-expansion circuit breaker is simulated numerically by finite element method and the influence of PTFE vapour on the arc is analysed with this model. The results reveal that the flow field inside the arc chamber is determined by the arc current, the arcing time, the nozzle arc and the clogging of its thermal boundary. The establishment of quenching pressure relies on both SF6 gas and PTFE vapour that absorbed arc energy in the nozzle. The PTFE vapour leads to an increase in the pressure of nozzle arc obviously, and a decrease in the temperature of arc. But it enhances the temperature of arc at zero current and slows down the decreasing rate of arc temperature as the current decreases.
Solid state light source driver establishing buck or boost operation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Palmer, Fred
A solid state light source driver circuit that operates in either a buck convertor or a boost convertor configuration is provided. The driver circuit includes a controller, a boost switch circuit and a buck switch circuit, each coupled to the controller, and a feedback circuit, coupled to the light source. The feedback circuit provides feedback to the controller, representing a DC output of the driver circuit. The controller controls the boost switch circuit and the buck switch circuit in response to the feedback signal, to regulate current to the light source. The controller places the driver circuit in its boostmore » converter configuration when the DC output is less than a rectified AC voltage coupled to the driver circuit at an input node. The controller places the driver circuit in its buck converter configuration when the DC output is greater than the rectified AC voltage at the input node.« less
NASA Astrophysics Data System (ADS)
Wei, Hai-Rui; Deng, Fu-Guo
2013-10-01
Constructing compact quantum circuits for universal quantum gates on solid-state systems is crucial for quantum computing. We present some compact quantum circuits for a deterministic solid-state quantum computing, including the cnot, Toffoli, and Fredkin gates on the diamond NV centers confined inside cavities, achieved by some input-output processes of a single photon. Our quantum circuits for these universal quantum gates are simple and economic. Moreover, additional electron qubits are not employed, but only a single-photon medium. These gates have a long coherent time. We discuss the feasibility of these universal solid-state quantum gates, concluding that they are feasible with current technology.
46 CFR 111.30-15 - Nameplates.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 46 Shipping 4 2011-10-01 2011-10-01 false Nameplates. 111.30-15 Section 111.30-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL... function. (b) Each nameplate for a circuit breaker must show the electrical load served and the setting of...
46 CFR 111.30-15 - Nameplates.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 46 Shipping 4 2013-10-01 2013-10-01 false Nameplates. 111.30-15 Section 111.30-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL... function. (b) Each nameplate for a circuit breaker must show the electrical load served and the setting of...
46 CFR 111.30-15 - Nameplates.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 46 Shipping 4 2010-10-01 2010-10-01 false Nameplates. 111.30-15 Section 111.30-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL... function. (b) Each nameplate for a circuit breaker must show the electrical load served and the setting of...
46 CFR 111.30-15 - Nameplates.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 46 Shipping 4 2012-10-01 2012-10-01 false Nameplates. 111.30-15 Section 111.30-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL... function. (b) Each nameplate for a circuit breaker must show the electrical load served and the setting of...
46 CFR 111.30-15 - Nameplates.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 46 Shipping 4 2014-10-01 2014-10-01 false Nameplates. 111.30-15 Section 111.30-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL... function. (b) Each nameplate for a circuit breaker must show the electrical load served and the setting of...
ERIC Educational Resources Information Center
Physics Education, 1984
1984-01-01
Describes (1) use of VELA (a stand-alone programmable instrument); (2) forced harmonic motion of galvanometers; (3) holographic interferometry and measurement of small angular displacement; and (4) an analogy useful on teaching capacitors at A-level. Also describes a comparison of fuses and circuit breakers using a microcomputer as a storage…
78 FR 23691 - Airworthiness Directives; the Boeing Company
Federal Register 2010, 2011, 2012, 2013, 2014
2013-04-22
... off electrical power to the in-flight entertainment (IFE) systems and other non-essential electrical...., Washington, DC 20590. FOR FURTHER INFORMATION CONTACT: Ray Mei, Aerospace Engineer, Systems and Equipment... circuit breaker, relays, and wiring to allow the flightcrew to turn off electrical power to the IFE...
Code of Federal Regulations, 2010 CFR
2010-10-01
....225-7036. (15) __252.225-7038, Restriction on Acquisition of Air Circuit Breakers (JUN 2005) (10 U.S.C... Data (SEP 1999) (10 U.S.C. 2321). (19) __252.232-7003, Electronic Submission of Payment Requests and...
78 FR 8058 - Airworthiness Directives; Fokker Services B.V. Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2013-02-05
... torque values of nuts on circuit breakers, contactors, and terminal blocks of the electrical power center... loose nuts, which could result in arcing and potentially an onboard fire, possibly resulting in damage... were issued, several operators reported finding loose nuts on contactors in the EPC of Fokker 50/60...
Code of Federal Regulations, 2013 CFR
2013-10-01
... Power Sources and Distribution Systems § 129.390 Shore power. Each vessel that has an electrical system... the switchboard or main distribution panel for the shore-power connection. (d) The circuit breaker... 46 Shipping 4 2013-10-01 2013-10-01 false Shore power. 129.390 Section 129.390 Shipping COAST...
Code of Federal Regulations, 2012 CFR
2012-10-01
... Power Sources and Distribution Systems § 129.390 Shore power. Each vessel that has an electrical system... the switchboard or main distribution panel for the shore-power connection. (d) The circuit breaker... 46 Shipping 4 2012-10-01 2012-10-01 false Shore power. 129.390 Section 129.390 Shipping COAST...
Code of Federal Regulations, 2014 CFR
2014-10-01
... Power Sources and Distribution Systems § 129.390 Shore power. Each vessel that has an electrical system... the switchboard or main distribution panel for the shore-power connection. (d) The circuit breaker... 46 Shipping 4 2014-10-01 2014-10-01 false Shore power. 129.390 Section 129.390 Shipping COAST...
Code of Federal Regulations, 2011 CFR
2011-10-01
... Power Sources and Distribution Systems § 129.390 Shore power. Each vessel that has an electrical system... the switchboard or main distribution panel for the shore-power connection. (d) The circuit breaker... 46 Shipping 4 2011-10-01 2011-10-01 false Shore power. 129.390 Section 129.390 Shipping COAST...
77 FR 64699 - Airworthiness Directives; Agusta S.p.A. Helicopters
Federal Register 2010, 2011, 2012, 2013, 2014
2012-10-23
... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA-2012... electrical load. This AD was prompted by an electrical failure on an Agusta Model A109E helicopter that... of the circuit breaker, loss of electrical power to instruments powered by the ``BATT BUS'' system...
77 FR 729 - Airworthiness Directives; Enstrom Helicopter Corporation Helicopters
Federal Register 2010, 2011, 2012, 2013, 2014
2012-01-06
... subsequent loss of control of the helicopter. DATES: This AD becomes effective January 23, 2012. The Director... Program Manager, FAA, Chicago Aircraft Certification Office, 2300 East Devon Avenue, Room 107, Des Plaines... the circuit breaker to trip before any significant loss of control occurs. After the trim actuator...
49 CFR 238.305 - Interior calendar day mechanical inspection of passenger cars.
Code of Federal Regulations, 2012 CFR
2012-10-01
..., circuit breakers, contactors, relays, grid resistors, and fuses are installed in non-hazardous locations... has access to the record upon request. (2) The written or electronic record must contain the following...) Any non-complying conditions found; and (iv) The signature or electronic identification of the...
49 CFR 238.305 - Interior calendar day mechanical inspection of passenger cars.
Code of Federal Regulations, 2011 CFR
2011-10-01
..., circuit breakers, contactors, relays, grid resistors, and fuses are installed in non-hazardous locations... has access to the record upon request. (2) The written or electronic record must contain the following...) Any non-complying conditions found; and (iv) The signature or electronic identification of the...
49 CFR 238.305 - Interior calendar day mechanical inspection of passenger cars.
Code of Federal Regulations, 2013 CFR
2013-10-01
..., circuit breakers, contactors, relays, grid resistors, and fuses are installed in non-hazardous locations... has access to the record upon request. (2) The written or electronic record must contain the following...) Any non-complying conditions found; and (iv) The signature or electronic identification of the...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-12-16
... regarding decisions to pause trading and continue to reduce the negative impacts of sudden, unanticipated price movements in Circuit Breaker Securities. The Exchange believes that the pilot is working well... proposal, the Commission has considered the proposed rule's impact on efficiency, competition, and capital...
In-line task 57: Component evaluation. [of circuit breakers, panel switches, etc. for space shuttle
NASA Technical Reports Server (NTRS)
Boykin, J. C.
1974-01-01
Design analysis tests were performed on selected power switching components to determine the possible applicability of off-the-shelf hardware to space shuttles. Various characteristics were also evaluated in those devices to determine the most desirable properties for the space shuttle.
Optically triggered high voltage switch network and method for switching a high voltage
El-Sharkawi, Mohamed A.; Andexler, George; Silberkleit, Lee I.
1993-01-19
An optically triggered solid state switch and method for switching a high voltage electrical current. A plurality of solid state switches (350) are connected in series for controlling electrical current flow between a compensation capacitor (112) and ground in a reactive power compensator (50, 50') that monitors the voltage and current flowing through each of three distribution lines (52a, 52b and 52c), which are supplying three-phase power to one or more inductive loads. An optical transmitter (100) controlled by the reactive power compensation system produces light pulses that are conveyed over optical fibers (102) to a switch driver (110') that includes a plurality of series connected optical triger circuits (288). Each of the optical trigger circuits controls a pair of the solid state switches and includes a plurality of series connected resistors (294, 326, 330, and 334) that equalize or balance the potential across the plurality of trigger circuits. The trigger circuits are connected to one of the distribution lines through a trigger capacitor (340). In each switch driver, the light signals activate a phototransistor (300) so that an electrical current flows from one of the energy reservoir capacitors through a pulse transformer (306) in the trigger circuit, producing gate signals that turn on the pair of serially connected solid state switches (350).
Observation of copper atoms behavior in a vacuum arc discharge using laser spectroscopy
NASA Astrophysics Data System (ADS)
Sung, Y. M.; Hayashi, Y.; Okraku-Yirenkyi, Y.; Otsubo, M.; Honda, C.; Sakoda, T.
2003-01-01
In order to investigate the most important parameters influencing the breaking characteristic of a vacuum circuit breaker (VCB), the behavior of copper (Cu) particles emitted from electrodes designed as an imitation of a vacuum valve of the VCB was observed. The temporal-spatial intensity distributions due to Cu particles in an excited state or a neutral state were measured using the laser induced fluorescence (LIF) technique and a charge coupled device camera attached with a special filter. The diffusion velocity of a Cu atom was also investigated by evaluating a Doppler shift of the LIF signal. The results showed that most Cu particles were emitted from the anode and were in an excited state or an ionized state during an arc discharge. Also, Cu particles were distributed between electrodes even after the discharge chocked, and its diffusion velocity in the direction of the cathode from the anode was about 2.6 km/s.
GPS synchronized power system phase angle measurements
NASA Astrophysics Data System (ADS)
Wilson, Robert E.; Sterlina, Patrick S.
1994-09-01
This paper discusses the use of Global Positioning System (GPS) synchronized equipment for the measurement and analysis of key power system quantities. Two GPS synchronized phasor measurement units (PMU) were installed before testing. It was indicated that PMUs recorded the dynamic response of the power system phase angles when the northern California power grid was excited by the artificial short circuits. Power system planning engineers perform detailed computer generated simulations of the dynamic response of the power system to naturally occurring short circuits. The computer simulations use models of transmission lines, transformers, circuit breakers, and other high voltage components. This work will compare computer simulations of the same event with field measurement.
Lockout/Tagout (LOTO) Simulator
NASA Technical Reports Server (NTRS)
Scheer, Jennifer
2011-01-01
The Lockout/Tagout (LOTO) Simulator is a portable training aid, or demonstration tool, designed to physically illustrate real-time critical-safety concepts of electrical lockout/tagout. The objective is to prevent misinterpretations of what is off and what is on during maintenance and repair of complex electrical systems. The simulator is designed in the form of a hinged box that opens up and stands on its own as an easel for demonstrations. On the outer face of the unit is a simulated circuit breaker box housing the switches. The breakers control the main power to the unit, a light bulb, and an electrical control cabinet. The light bulb is wired so that either of two breakers can provide power to it. When power is sent to the electrical control cabinet, a red indicator light illuminates. Inside the cabinet is the power supply from a personal computer. The power supply produces a 12-V dc output that is sent over to a small fan next to it, also from a computer, and an amber light on the front of the cabinet illuminates. A separate switch powers the fan on and off. The power supply is behind a plastic shield to protect against exposure to live conductors. Electrical banana jacks are mounted in the plastic shield to allow a voltmeter to be connected safely when opening the cabinet and taking a meter reading to verify de-energization as part of a simulation exercise. This LOTO simulator prototype is designed and fabricated as an all-in-one unit. All accessories can be stored inside the hinged case, and there is a handle on top for ease of transport. The circuit breaker labels attach with hook and loop fasteners so that they may be moved and changed to fit the training or demonstration scenario. The warning signs and labels on the electrical control box are magnetic, allowing for easy reconfiguration to emulate different equipment setups. A specially designed magnetic cover was made to disguise the indicator lights for demonstrations when these indicators are not used. The cover is disguised as an arc flash safety label that would typically be found on such a cabinet. One indicator light has a separate switch that can take it offline. This is to allow for demonstration to trainees on why it is important not to completely rely on indicator lights, but that they should always take a meter reading at the exposed conductors to absolutely verify de-energization before exposure. A clear plastic barrier and banana jacks inside the cabinet provide a safe way to plug in a voltmeter for demonstrations without exposure to the hazards of energized equipment. A small remote control unit is wired into the fan circuit. The remote allows the demonstrator to turn the fan on and off, provided that all of the breakers and switches leading to it are configured on as well. The remote feature was added in order to demonstrate the importance of starting the lockout/tagout task with energized equipment, then powering it down, isolating it, and locking it out to ensure that the correct breakers have been locked out.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-05-12
... extraordinary market volatility (``Trading Pause'') in all stocks included in the S&P 500 Index (``S&P 500... mechanism to address extraordinary market volatility, if adopted, applies to the Circuit Breaker Stocks. See... a limit up-limit down mechanism to address extraordinary market volatility, if adopted, applies to...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-08-16
... volatility, if adopted, applies]. During the pilot, the term ``Circuit Breaker Securities'' shall mean all.... (collectively, the ``Exchanges''), to pause trading during periods of extraordinary market volatility in S&P 500... extraordinary market volatility, if adopted, applies.\\7\\ On June 23, 2011, the Commission approved the expansion...
11. INTERIOR VIEW OF OPERATING HOUSE NO. 4, SHOWING WORM ...
11. INTERIOR VIEW OF OPERATING HOUSE NO. 4, SHOWING WORM WHEEL GEAR ASSEMBLY, ORIGINAL 20 HP EAST HOIST MOTOR, AND CONTROL GATES 7 AND 8 HAND BRAKES, WITH MOTOR SELECTOR SWITCH, MOTOR STARTING SWITCH, AND OIL CIRCUIT BREAKER IN BACKGROUND - Long Lake Hydroelectric Plant, Spillway Dam, Spanning Spokane River, Ford, Stevens County, WA
78 FR 60334 - Proposed Collection; Comment Request
Federal Register 2010, 2011, 2012, 2013, 2014
2013-10-01
...'') for extension and approval. Rule 201 is a short sale-related circuit breaker rule that, if triggered... trading centers do not execute or display any impermissibly priced short sale orders, unless an order is... or display a short sale order without regard to whether the short sale order is at a price that is...
78 FR 27310 - Airworthiness Directives; the Boeing Company Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2013-05-10
... wiring; installation of new circuit breakers, relays, relay connectors, and wiring; and replacement of... Installation of wiring and changing 36 work-hours x $85 per $2,503 $5,563 $328,217 ELMS panel wiring. hour = $3... flames in the passenger cabin of various transport category airplanes related to the wiring for the...
Code of Federal Regulations, 2011 CFR
2011-10-01
... be a lockable circuit breaker or lockable switch that disconnects power to the motor. (e) Cargo Tanks.../vacuum valves with an unlimited height; or (4) Within 10 meters (33 ft) of vent outlets for free flow of...
Code of Federal Regulations, 2012 CFR
2012-10-01
... be a lockable circuit breaker or lockable switch that disconnects power to the motor. (e) Cargo Tanks.../vacuum valves with an unlimited height; or (4) Within 10 meters (33 ft) of vent outlets for free flow of...
Code of Federal Regulations, 2010 CFR
2010-10-01
... be a lockable circuit breaker or lockable switch that disconnects power to the motor. (e) Cargo Tanks.../vacuum valves with an unlimited height; or (4) Within 10 meters (33 ft) of vent outlets for free flow of...
Wang, Zhixiang; Jones, Gordon R.; Spencer, Joseph W.; Wang, Xiaohua; Rong, Mingzhe
2017-01-01
Contact erosion is one of the most crucial factors affecting the electrical service lifetime of high-voltage circuit breakers (HVCBs). On-line monitoring the contacts’ erosion degree is increasingly in demand for the sake of condition based maintenance to guarantee the functional operation of HVCBs. A spectroscopic monitoring system has been designed based upon a commercial 245 kV/40 kA SF6 live tank circuit breaker with copper–tungsten (28 wt % and 72 wt %) arcing contacts at atmospheric SF6 pressure. Three optical-fibre based sensors are used to capture the time-resolved spectra of arcs. A novel approach using chromatic methods to process the time-resolved spectral signal has been proposed. The processed chromatic parameters have been interpreted to show that the time variation of spectral emission from the contact material and quenching gas are closely correlated to the mass loss and surface degradation of the plug arcing contact. The feasibility of applying this method to online monitoring of contact erosion is indicated. PMID:28272295
Wang, Zhixiang; Jones, Gordon R; Spencer, Joseph W; Wang, Xiaohua; Rong, Mingzhe
2017-03-06
Contact erosion is one of the most crucial factors affecting the electrical service lifetime of high-voltage circuit breakers (HVCBs). On-line monitoring the contacts' erosion degree is increasingly in demand for the sake of condition based maintenance to guarantee the functional operation of HVCBs. A spectroscopic monitoring system has been designed based upon a commercial 245 kV/40 kA S F 6 live tank circuit breaker with copper-tungsten (28 wt % and 72 wt %) arcing contacts at atmospheric S F 6 pressure. Three optical-fibre based sensors are used to capture the time-resolved spectra of arcs. A novel approach using chromatic methods to process the time-resolved spectral signal has been proposed. The processed chromatic parameters have been interpreted to show that the time variation of spectral emission from the contact material and quenching gas are closely correlated to the mass loss and surface degradation of the plug arcing contact. The feasibility of applying this method to online monitoring of contact erosion is indicated.
Korpinen, Leena; Pääkkönen, Rauno
2018-02-26
The objective of the study was to investigate occupational exposure to electric fields during the task 'maintenance of an operating device of circuit breaker from a service platform' at 110-kV substations. The aim was also to compare the results to Directive 2013/35/EU. At 16 substations, 255 electric field measurements were performed. The highest mean value of the electric fields was 9.6 kV⋅m -1 . At 63% of substations the maximum values were over 10.0 kV⋅m -1 , and at 31% of the substations the 75th percentiles were over 10.0 kV⋅m -1 , which is the low action level (AL) according to Directive 2013/35/EU. All measured values were below the high AL (20.0 kV⋅m -1 ). In the future, it is important to take into account that the measurements were only taken at Finnish 110-kV substations; therefore, it is not possible to generalize these results to other countries and different types of substations.
Insulation co-ordination aspects for power stations with generator circuit-breakers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sanders, M.; Koeppl, G.; Kreuzer, J.
1995-07-01
The generator circuit-breaker (gen. c.b.) located between the generator and the step-up transformer, is now being applied world-wide. It has become a recognized electrical component of power stations which is largely due to economical advantages and increased power station availability. Technical protection considerations for power stations have always been the reason for discussion and the object of improvement. With the use of a gen. c.b., some points of view need to be considered anew. Not only the protection system in case of fault conditions will be influenced, but also the insulation co-ordination philosophy. Below the results of some calculations concerningmore » expected overvoltages are presented. These calculations are based on a transformer rated 264/15.5kV, 220 MVA. But the results are transferable to other power plants. Some measurements carried out on a transformer of the same rating complement the calculations. The findings may contribute to an improvement in insulation co-ordination and protection of the electrical system generator--step-up transformer.« less
Solid state remote circuit selector switch
NASA Technical Reports Server (NTRS)
Peterson, V. S.
1970-01-01
Remote switching circuit utilizes voltage logic to switch on desired circuit. Circuit controls rotating multi-range pressure transducers in jet engine testing and can be used in coded remote circuit activator where sequence of switching has to occur in defined length of time to prevent false or undesired circuit activation.
2007-09-13
The instruments that make up the Ames Autonomous Module Scanner (AMS) that provided precise thermal-infrared imaging during the Western States Fire Mission in 2007 are detailed in this photo of the AMS as mounted on Ikhana's pod tray. The large foil-covered foam-insulated box at left covers the pressure vessel containing the data system computers and other electronics. The round white-topped assembly is the scan head, including the scan mirror, folded telescope, blackbody references, spectrometer and detectors. Two pressure boxes visible at the forward end of the tray contain the Applanix POS/AV precision navigation subsystem (black) and the power distributor including circuit breakers and ancillary wiring, scan motor controller and the blackbody reference temperature controller (blue).
Rectifier cabinet static breaker
Costantino, Jr, Roger A.; Gliebe, Ronald J.
1992-09-01
A rectifier cabinet static breaker replaces a blocking diode pair with an SCR and the installation of a power transistor in parallel with the latch contactor to commutate the SCR to the off state. The SCR serves as a static breaker with fast turnoff capability providing an alternative way of achieving reactor scram in addition to performing the function of the replaced blocking diodes. The control circuitry for the rectifier cabinet static breaker includes on-line test capability and an LED indicator light to denote successful test completion. Current limit circuitry provides high-speed protection in the event of overload.
Solid state control system for oil well bailer pump
DOE Office of Scientific and Technical Information (OSTI.GOV)
Senghaas, K. A.; Senghaas, P.
1985-05-14
A solid state switching controller for use with various types of oil well bailer pumps. Individually programmable steps with lockouts provide multiple mutual exclusivity between various circuit operations. A trickle charge battery system powers the control circuits. A tank overflow float protects against oil spillage. An automatic production rate adjustment circuit is provided which increases cycle time in proportion to the rate of production. The circuit includes a low power voltage detector for disabling the control circuits until the line voltage is acceptable. A three-phase power and control system with an isolation transformer for the controls avoids unreliable ground connections.more » The timers include a dividing circuit with an RC circuit. All power actuated apparatus are actuated by triac switches which are controlled by an opto driver. The bailer brake is pulse actuated for allowing the bailer to sink into crude oil without excess cable looseness.« less
Digital Systems Validation Handbook. Volume 2
1989-02-01
power. 2. A grid of wires, solid sheet, or foil. 3. A wire from circuit to grounding block or case. 4. A wire from circuit to structure. 5. Shield...RETURN. (11) 1. Structure, for power, fault, and "discrete" circuits. 2. A grid of wires, solid sheet, or foil. 3. A wire from circuit load back to...TV (14) Television TWTD (13) Thin Wire Time Domain TX (5) Transmit U.K. (13,141 United Kingdom U.S. (14) United States UART (15) Universal Asynchronous
Federal Register 2010, 2011, 2012, 2013, 2014
2011-03-01
..., 2011. I. Introduction On January 14, 2011, BATS Exchange, Inc. (the ``Exchange'' or ``BATS'') filed...\\ pursuant to which, among other things, short sale orders in covered securities \\6\\ generally cannot be... the current national best bid (``NBB'') when a short sale circuit breaker is in effect for the covered...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-03-01
... 23, 2011. I. Introduction On January 14, 2011, BATS Y-Exchange, Inc. (the ``Exchange'' or ``BYX... Rule 201,\\5\\ pursuant to which, among other things, short sale orders in covered securities \\6... the current national best bid (``NBB'') when a short sale circuit breaker is in effect for the covered...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-10-19
..., particularly in times of market stress, and exacerbate market volatility.\\8\\ \\7\\ See BATS Letter at 2; Deutsche... Volatility Guard to work within the parameters of the recently adopted single-stock circuit breakers, and to... of individual exchange volatility moderators in times of market stress. In addition, as noted above...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-08
... volatility, if adopted, applies. The text of the proposed rule change is below. Proposed new language is... volatility, if adopted, applies[April 11, 2011]. During the pilot, the term ``Circuit Breaker Securities... of extraordinary market volatility in S&P 500 stocks.\\3\\ The rules require the Listing Markets \\4\\ to...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-02-20
... to Address Extraordinary Market Volatility or February 4, 2014. The text of the proposed rule change... Extraordinary Market Volatility or February 4, 2014[3]. During the pilot, the term ``Circuit Breaker Securities... periods of extraordinary market volatility in S&P 500 stocks.\\3\\ The rules require the Listing Markets \\4...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-02-20
... Extraordinary Market Volatility or February 4, 2014. The text of the proposed rule change is below. Proposed new... Extraordinary Market Volatility or February 4, 2014[3]. During the pilot, the term ``Circuit Breaker Securities... ``Exchanges''), to pause trading during periods of extraordinary market volatility in S&P 500 stocks.\\3\\ The...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-08-16
... market volatility, if adopted, applies]. During the pilot, the term ``Circuit Breaker Securities'' shall... volatility in S&P 500 stocks.\\3\\ The rules require the Listing Markets \\4\\ to issue five-minute trading... volatility, if adopted, applies.\\9\\ On June 23, 2011, the Commission approved the expansion of the pilot to...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-04-11
... time period before suddenly reversing to prices consistent with their pre-decline levels.\\5\\ This... implemented through a series of rule filings by the equity exchanges and by FINRA.\\6\\ The single-stock circuit breaker was designed to reduce extraordinary market volatility in NMS stocks by imposing a five-minute...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-12
... uniformity regarding decisions to pause trading and continue to reduce the negative impacts of sudden, unanticipated price movements in Circuit Breaker Securities. The Exchange believes that the pilot is working... the proposed rule's impact on efficiency, competition, and capital formation. See 15 U.S.C. 78c(f). At...
NASA Astrophysics Data System (ADS)
Cheng, Xian; Duan, Xiongying; Liao, Minfu; Huang, Zhihui; Luo, Yan; Zou, Jiyan
2013-08-01
Hybrid circuit breaker (HCB) technology based on a vacuum interrupter and a SF6 interrupter in series has become a new research direction because of the low-carbon requirements for high voltage switches. The vacuum interrupter has an excellent ability to deal with the steep rising part of the transient recovery voltage (TRV), while the SF6 interrupter can withstand the peak part of the voltage easily. An HCB can take advantage of the interrupters in the current interruption process. In this study, an HCB model based on the vacuum ion diffusion equations, ion density equation, and modified Cassie-Mayr arc equation is explored. A simulation platform is constructed by using a set of software called the alternative transient program (ATP). An HCB prototype is also designed, and the short circuit current is interrupted by the HCB under different action sequences of contacts. The voltage distribution of the HCB is analyzed through simulations and tests. The results demonstrate that if the vacuum interrupter withstands the initial TRV and interrupts the post-arc current first, then the recovery speed of the dielectric strength of the SF6 interrupter will be fast. The voltage distribution between two interrupters is determined by their post-arc resistance, which happens after current-zero, and subsequently, it is determined by the capacitive impedance after the post-arc current decays to zero.
Electrical resistivity well-logging system with solid-state electronic circuitry
Scott, James Henry; Farstad, Arnold J.
1977-01-01
An improved 4-channel electrical resistivity well-logging system for use with a passive probe with electrodes arranged in the 'normal' configuration has been designed and fabricated by Westinghouse Electric Corporation to meet technical specifications developed by the U.S. Geological Survey. Salient features of the system include solid-state switching and current regulation in the transmitter circuit to produce a constant-current source square wave, and synchronous solid-state switching and sampling of the potential waveform in the receiver circuit to provide an analog dc voltage proportions to the measured resistivity. Technical specifications and design details are included in this report.
Three types of solid state remote power controllers
NASA Technical Reports Server (NTRS)
Baker, D. E.
1975-01-01
Three types of solid state Remote Power Controller (RPC) circuits for 120 Vdc spacecraft distribution systems have been developed and evaluated. Both current limiting and noncurrent limiting modes of overload protection were developed and were demonstrated to be feasible. A second generation of circuits was developed which offers comparable performance with substantially less cost and complexity. Electrical efficiency for both generations is 98.5 to 99%. This paper describes various aspects of the circuit design, trade-off studies, and experimental test results. Comparisons of design parameters, component requirements, and engineering model evaluations will emphasize the high efficiency and reliability of the designs.
NASA Astrophysics Data System (ADS)
Arata, Shigeki; Hayashi, Kenya; Nishio, Yuya; Kobayashi, Atsuki; Nakazato, Kazuo; Niitsu, Kiichi
2018-04-01
The world’s smallest (0.36 mm2) solid-state CMOS-compatible glucose fuel cell, which exhibits an open-circuit voltage (OCV) of 228 mV and a power generation density of 1.32 µW/cm2 with a 30 mM glucose solution, is reported in this paper. Compared with conventional wet etching, dry etching (reactive ion etching) for patterning minimizes damage to the anode and cathode, resulting in a cell with a small size and a high OCV, sufficient for CMOS circuit operation.
Variable-pulse switching circuit accurately controls solenoid-valve actuations
NASA Technical Reports Server (NTRS)
Gillett, J. D.
1967-01-01
Solid state circuit generating adjustable square wave pulses of sufficient power operates a 28 volt dc solenoid valve at precise time intervals. This circuit is used for precise time control of fluid flow in combustion experiments.
Apparatus for and method of testing an electrical ground fault circuit interrupt device
Andrews, L.B.
1998-08-18
An apparatus for testing a ground fault circuit interrupt device includes a processor, an input device connected to the processor for receiving input from an operator, a storage media connected to the processor for storing test data, an output device connected to the processor for outputting information corresponding to the test data to the operator, and a calibrated variable load circuit connected between the processor and the ground fault circuit interrupt device. The ground fault circuit interrupt device is configured to trip a corresponding circuit breaker. The processor is configured to receive signals from the calibrated variable load circuit and to process the signals to determine a trip threshold current and/or a trip time. A method of testing the ground fault circuit interrupt device includes a first step of providing an identification for the ground fault circuit interrupt device. Test data is then recorded in accordance with the identification. By comparing test data from an initial test with test data from a subsequent test, a trend of performance for the ground fault circuit interrupt device is determined. 17 figs.
Apparatus for and method of testing an electrical ground fault circuit interrupt device
Andrews, Lowell B.
1998-01-01
An apparatus for testing a ground fault circuit interrupt device includes a processor, an input device connected to the processor for receiving input from an operator, a storage media connected to the processor for storing test data, an output device connected to the processor for outputting information corresponding to the test data to the operator, and a calibrated variable load circuit connected between the processor and the ground fault circuit interrupt device. The ground fault circuit interrupt device is configured to trip a corresponding circuit breaker. The processor is configured to receive signals from the calibrated variable load circuit and to process the signals to determine a trip threshold current and/or a trip time. A method of testing the ground fault circuit interrupt device includes a first step of providing an identification for the ground fault circuit interrupt device. Test data is then recorded in accordance with the identification. By comparing test data from an initial test with test data from a subsequent test, a trend of performance for the ground fault circuit interrupt device is determined.
Huang, Nantian; Chen, Huaijin; Cai, Guowei; Fang, Lihua; Wang, Yuqiang
2016-11-10
Mechanical fault diagnosis of high-voltage circuit breakers (HVCBs) based on vibration signal analysis is one of the most significant issues in improving the reliability and reducing the outage cost for power systems. The limitation of training samples and types of machine faults in HVCBs causes the existing mechanical fault diagnostic methods to recognize new types of machine faults easily without training samples as either a normal condition or a wrong fault type. A new mechanical fault diagnosis method for HVCBs based on variational mode decomposition (VMD) and multi-layer classifier (MLC) is proposed to improve the accuracy of fault diagnosis. First, HVCB vibration signals during operation are measured using an acceleration sensor. Second, a VMD algorithm is used to decompose the vibration signals into several intrinsic mode functions (IMFs). The IMF matrix is divided into submatrices to compute the local singular values (LSV). The maximum singular values of each submatrix are selected as the feature vectors for fault diagnosis. Finally, a MLC composed of two one-class support vector machines (OCSVMs) and a support vector machine (SVM) is constructed to identify the fault type. Two layers of independent OCSVM are adopted to distinguish normal or fault conditions with known or unknown fault types, respectively. On this basis, SVM recognizes the specific fault type. Real diagnostic experiments are conducted with a real SF₆ HVCB with normal and fault states. Three different faults (i.e., jam fault of the iron core, looseness of the base screw, and poor lubrication of the connecting lever) are simulated in a field experiment on a real HVCB to test the feasibility of the proposed method. Results show that the classification accuracy of the new method is superior to other traditional methods.
Huang, Nantian; Chen, Huaijin; Cai, Guowei; Fang, Lihua; Wang, Yuqiang
2016-01-01
Mechanical fault diagnosis of high-voltage circuit breakers (HVCBs) based on vibration signal analysis is one of the most significant issues in improving the reliability and reducing the outage cost for power systems. The limitation of training samples and types of machine faults in HVCBs causes the existing mechanical fault diagnostic methods to recognize new types of machine faults easily without training samples as either a normal condition or a wrong fault type. A new mechanical fault diagnosis method for HVCBs based on variational mode decomposition (VMD) and multi-layer classifier (MLC) is proposed to improve the accuracy of fault diagnosis. First, HVCB vibration signals during operation are measured using an acceleration sensor. Second, a VMD algorithm is used to decompose the vibration signals into several intrinsic mode functions (IMFs). The IMF matrix is divided into submatrices to compute the local singular values (LSV). The maximum singular values of each submatrix are selected as the feature vectors for fault diagnosis. Finally, a MLC composed of two one-class support vector machines (OCSVMs) and a support vector machine (SVM) is constructed to identify the fault type. Two layers of independent OCSVM are adopted to distinguish normal or fault conditions with known or unknown fault types, respectively. On this basis, SVM recognizes the specific fault type. Real diagnostic experiments are conducted with a real SF6 HVCB with normal and fault states. Three different faults (i.e., jam fault of the iron core, looseness of the base screw, and poor lubrication of the connecting lever) are simulated in a field experiment on a real HVCB to test the feasibility of the proposed method. Results show that the classification accuracy of the new method is superior to other traditional methods. PMID:27834902
Compact high voltage solid state switch
Glidden, Steven C.
2003-09-23
A compact, solid state, high voltage switch capable of high conduction current with a high rate of current risetime (high di/dt) that can be used to replace thyratrons in existing and new applications. The switch has multiple thyristors packaged in a single enclosure. Each thyristor has its own gate drive circuit that circuit obtains its energy from the energy that is being switched in the main circuit. The gate drives are triggered with a low voltage, low current pulse isolated by a small inexpensive transformer. The gate circuits can also be triggered with an optical signal, eliminating the trigger transformer altogether. This approach makes it easier to connect many thyristors in series to obtain the hold off voltages of greater than 80 kV.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-08-15
... Volatility, was approved by the Commission on June 10, 2010 on a pilot basis. The pilot is currently set to... extraordinary market volatility, if adopted, applies to the Circuit Breaker Stocks.\\5\\ The rule was developed in... individual stocks that experience rapid price movement.\\6\\ As the duration of the pilot expires on the...
Haas, Edwin Gerard; Beauman, Ronald; Palo, Jr., Stefan
2013-01-29
The invention provides a device and method for actuating electrical switches remotely. The device is removably attached to the switch and is actuated through the transfer of a user's force. The user is able to remain physically removed from the switch site obviating need for protective equipment. The device and method allow rapid, safe actuation of high-voltage or high-current carrying electrical switches or circuit breakers.
17 CFR 242.201 - Circuit breaker.
Code of Federal Regulations, 2013 CFR
2013-04-01
...) The term covered security shall mean any NMS stock as defined in § 242.600(b)(47). (2) The term effective transaction reporting plan for a covered security shall have the same meaning as in § 242.600(b... shall have the same meaning as in § 242.600(b)(42). (5) The term odd lot shall have the same meaning as...
17 CFR 242.201 - Circuit breaker.
Code of Federal Regulations, 2014 CFR
2014-04-01
...) The term covered security shall mean any NMS stock as defined in § 242.600(b)(47). (2) The term effective transaction reporting plan for a covered security shall have the same meaning as in § 242.600(b... shall have the same meaning as in § 242.600(b)(42). (5) The term odd lot shall have the same meaning as...
17 CFR 242.201 - Circuit breaker.
Code of Federal Regulations, 2012 CFR
2012-04-01
...) The term covered security shall mean any NMS stock as defined in § 242.600(b)(47). (2) The term effective transaction reporting plan for a covered security shall have the same meaning as in § 242.600(b... shall have the same meaning as in § 242.600(b)(42). (5) The term odd lot shall have the same meaning as...
17 CFR 242.201 - Circuit breaker.
Code of Federal Regulations, 2011 CFR
2011-04-01
...) The term covered security shall mean any NMS stock as defined in § 242.600(b)(47). (2) The term effective transaction reporting plan for a covered security shall have the same meaning as in § 242.600(b... shall have the same meaning as in § 242.600(b)(42). (5) The term odd lot shall have the same meaning as...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-12-16
... uniformity regarding decisions to pause trading and continue to reduce the negative impacts of sudden, unanticipated price movements in Circuit Breaker Securities. The Exchange believes that the pilot is working..., competition, and capital formation. See 15 U.S.C. 78c(f). At any time within 60 days of the filing of the...
Influence of condensed species on thermo-physical properties of LTE and non-LTE SF6-Cu mixture
NASA Astrophysics Data System (ADS)
Chen, Zhexin; Wu, Yi; Yang, Fei; Sun, Hao; Rong, Mingzhe; Wang, Chunlin
2017-10-01
SF6-Cu mixture is frequently formed in high-voltage circuit breakers due to the electrode erosion and metal vapor diffusion. During the interruption process, the multiphase effect and deviation from local thermal equilibrium (non-LTE assumption) can both affect the thermo-physical of the arc plasma and further influence the performance of circuit breaker. In this paper, thermo-physical properties, namely composition, thermodynamic properties and transport coefficients are calculated for multiphase SF6-Cu mixture with and without LTE assumption. The composition is confirmed by combining classical two-temperature mass action law with phase equilibrium condition deduced from second law of thermodynamics. The thermodynamic properties and transport coefficients are calculated using the multiphase composition result. The influence of condensed species on thermo-physical properties is discussed at different temperature, pressure (0.1-10 atm), non-equilibrium degrees (1-10), and copper molar proportions (0-50%). It is found that the multiphase effect has significant influence on specific enthalpy, specific heat and heavy species thermal conductivity in both LTE and non-LTE SF6-Cu system. This paper provides a more accurate database for computational fluid dynamic calculation.
Hybrid circuit achieves pulse regeneration with low power drain
NASA Technical Reports Server (NTRS)
Cancro, C. A.
1965-01-01
Hybrid tunnel diode-transistor circuit provides a solid-state, low power drain pulse regenerator, frequency limiter, or gated oscillator. When the feedback voltage exceeds the input voltage, the circuit functions as a pulse normalizer or a frequency limiter. If the circuit is direct coupled, it functions as a gated oscillator.
Optical Analysis Of The Vacuum Arc Plasma Generated In Cup-Shape Contacts
NASA Astrophysics Data System (ADS)
Pavelescu, G.; Pavelescu, D.; Dumitrescu, G.; Anghelita, P.; Gherendi, F.
2007-04-01
In this paper are presented the results of the optical analysis on the rotating arc plasma, generated in the vacuum low voltage circuit breaker with cup-shaped contacts. An adequate experimental setup was used for single shot time and spatial resolved spectroscopy in order to analyze the evolution of the vacuum arc plasma. Different current interruption situations are correlated with plasma spectral diagnosis. The study is aimed to contribute to a better understanding of the complex phenomena that take place in the interruption process of high currents that appears in the short-circuit regime of electrical networks.
Solid state circuit controls direction, speed, and braking of dc motor
NASA Technical Reports Server (NTRS)
Hanna, M. F.
1966-01-01
Full-wave bridge rectifier circuit controls the direction, speed, and braking of a dc motor. Gating in the circuit of Silicon Controlled Rectifiers /SCRS/ controls output polarity and braking is provided by an SCR that is gated to short circuit the reverse voltage generated by reversal of motor rotation.
Modeling of breakdown during the post-arc phase of a vacuum circuit breaker
NASA Astrophysics Data System (ADS)
Sarrailh, P.; Garrigues, L.; Boeuf, J. P.; Hagelaar, G. J. M.
2010-12-01
After a high-current interruption in a vacuum circuit breaker (VCB), the electrode gap is filled with a high density copper vapor plasma in a large copper vapor density (~1022 m-3). The copper vapor density is sustained by electrode evaporation. During the post-arc phase, a rapidly increasing voltage is applied to the gap, and a sheath forms and expands, expelling the plasma from the gap when circuit breaking is successful. There is, however, a risk of breakdown during that phase, leading to the failure of the VCB. Preventing breakdown during the post-arc phase is an important issue for the improvement of VCB reliability. In this paper, we analyze the risk of Townsend breakdown in the high copper vapor density during the post-arc phase using a numerical model that takes into account secondary electron emission, volume ionization, and plasma and neutral transport, for given electrode temperatures. The simulations show that fast neutrals created in the cathode sheath by charge exchange collisions with ions generate a very large secondary electron emission current that can lead to Townsend breakdown. The results also show that the risk of failure of the VCB due to Townsend breakdown strongly depends on the electrode temperatures (which govern the copper vapor density) and becomes important for temperatures greater than 2100 K, which can be reached in vacuum arcs. The simulations also predict that a hotter anode tends to increase the risk of Townsend breakdown.
Two color interferometric electron density measurement in an axially blown arc
NASA Astrophysics Data System (ADS)
Stoller, Patrick; Carstensen, Jan; Galletti, Bernardo; Doiron, Charles; Sokolov, Alexey; Salzmann, René; Simon, Sandor; Jabs, Philipp
2016-09-01
High voltage circuit breakers protect the power grid by interrupting the current in case of a short circuit. To do so an arc is ignited between two contacts as they separate; transonic gas flow is used to cool and ultimately extinguish the arc at a current-zero crossing of the alternating current. A detailed understanding of the arc interruption process is needed to improve circuit breaker design. The conductivity of the partially ionized gas remaining after the current-zero crossing, a key parameter in determining whether the arc will be interrupted or not, is a function of the electron density. The electron density, in turn, is a function of the detailed dynamics of the arc cooling process, which does not necessarily occur under local thermodynamic equilibrium (LTE) conditions. In this work, we measure the spatially resolved line-integrated index of refraction in a near-current-zero arc stabilized in an axial flow of synthetic air with two nanosecond pulsed lasers at wavelengths of 532 nm and 671 nm. Generating a stable, cylindrically symmetric arc enables us to determine the three-dimensional index of refraction distribution using Abel inversion. Due to the wavelength dependence of the component of the index of refraction related to the free electrons, the information at two different wavelengths can be used to determine the electron density. This information allows us to determine how important it is to take into account non-equilibrium effects for accurate modeling of the physics of decaying arcs.
Kilovolt dc solid state remote power controller development
NASA Technical Reports Server (NTRS)
Mitchell, J. T.
1982-01-01
The experience gained in developing and applying solid state power controller (SSPC) technology at high voltage dc (HVDC) potentials and power levels of up to 25 kilowatts is summarized. The HVDC switching devices, power switching concepts, drive circuits, and very fast acting overcurrent protection circuits were analyzed. A 25A bipolar breadboard with Darlington connected switching transistor was built. Fault testing at 900 volts was included. A bipolar transistor packaged breadboard design was developed. Power MOSFET remote power controller (RPC) was designed.
16. Bus Room (also known as Switch Gear Room), view ...
16. Bus Room (also known as Switch Gear Room), view to the southeast. An air circuit breaker compressor (visible in photograph number 2) was once attached to the main bus relay visible in the background of the photograph. - Washington Water Power Clark Fork River Cabinet Gorge Hydroelectric Development, Powerhouse, North Bank of Clark Fork River at Cabinet Gorge, Cabinet, Bonner County, ID
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chaves, Mario Paul
2017-07-01
For my project I have selected to research and design a high current pulse system, which will be externally triggered from a 5V pulse. The research will be conducted in the region of paralleling the solid state switches for a higher current output, as well as to see if there will be any other advantages in doing so. The end use of the paralleled solid state switches will be used on a Capacitive Discharge Unit (CDU). For the first part of my project, I have set my focus on the design of the circuit, selection of components, and simulation ofmore » the circuit.« less
NASA Astrophysics Data System (ADS)
Redondo, L. M.; Silva, J. Fernando; Canacsinh, H.; Ferrão, N.; Mendes, C.; Soares, R.; Schipper, J.; Fowler, A.
2010-07-01
A new circuit topology is proposed to replace the actual pulse transformer and thyratron based resonant modulator that supplies the 60 kV target potential for the ion acceleration of the On-Line Isotope Mass Separator accelerator, the stability of which is critical for the mass resolution downstream separator, at the European Organization for Nuclear Research. The improved modulator uses two solid-state switches working together, each one based on the Marx generator concept, operating as series and parallel switches, reducing the stress on the series stacked semiconductors, and also as auxiliary pulse generator in order to fulfill the target requirements. Preliminary results of a 10 kV prototype, using 1200 V insulated gate bipolar transistors and capacitors in the solid-state Marx circuits, ten stages each, with an electrical equivalent circuit of the target, are presented, demonstrating both the improved voltage stability and pulse flexibility potential wanted for this new modulator.
Novel Directional Protection Scheme for the FREEDM Smart Grid System
NASA Astrophysics Data System (ADS)
Sharma, Nitish
This research primarily deals with the design and validation of the protection system for a large scale meshed distribution system. The large scale system simulation (LSSS) is a system level PSCAD model which is used to validate component models for different time-scale platforms, to provide a virtual testing platform for the Future Renewable Electric Energy Delivery and Management (FREEDM) system. It is also used to validate the cases of power system protection, renewable energy integration and storage, and load profiles. The protection of the FREEDM system against any abnormal condition is one of the important tasks. The addition of distributed generation and power electronic based solid state transformer adds to the complexity of the protection. The FREEDM loop system has a fault current limiter and in addition, the Solid State Transformer (SST) limits the fault current at 2.0 per unit. Former students at ASU have developed the protection scheme using fiber-optic cable. However, during the NSF-FREEDM site visit, the National Science Foundation (NSF) team regarded the system incompatible for the long distances. Hence, a new protection scheme with a wireless scheme is presented in this thesis. The use of wireless communication is extended to protect the large scale meshed distributed generation from any fault. The trip signal generated by the pilot protection system is used to trigger the FID (fault isolation device) which is an electronic circuit breaker operation (switched off/opening the FIDs). The trip signal must be received and accepted by the SST, and it must block the SST operation immediately. A comprehensive protection system for the large scale meshed distribution system has been developed in PSCAD with the ability to quickly detect the faults. The validation of the protection system is performed by building a hardware model using commercial relays at the ASU power laboratory.
Quantitative secondary electron detection
DOE Office of Scientific and Technical Information (OSTI.GOV)
Agrawal, Jyoti; Joy, David C.; Nayak, Subuhadarshi
Quantitative Secondary Electron Detection (QSED) using the array of solid state devices (SSD) based electron-counters enable critical dimension metrology measurements in materials such as semiconductors, nanomaterials, and biological samples (FIG. 3). Methods and devices effect a quantitative detection of secondary electrons with the array of solid state detectors comprising a number of solid state detectors. An array senses the number of secondary electrons with a plurality of solid state detectors, counting the number of secondary electrons with a time to digital converter circuit in counter mode.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Volkov, M. S.; Gusev, Yu. P., E-mail: GusevYP@mpei.ru; Monakov, Yu. V.
The insertion of current-limiting reactors into electrical equipment operating at a voltage of 110 and 220 kV produces a change in the parameters of the transient recovery voltages at the contacts of the circuit breakers for disconnecting short circuits, which could be the reason for the increase in the duration of the short circuit, damage to the electrical equipment and losses in the power system. The results of mathematical modeling of the transients, caused by tripping of the short circuit in a reactive electric power transmission line are presented, and data are given on the negative effect of a current-limitingmore » resistor on the rate of increase and peak value of the transient recovery voltages. Methods of ensuring the standard requirements imposed on the parameters of the transient recovery voltages when using current-limiting reactors in the high-voltage electrical equipment of power plants and substations are proposed and analyzed.« less
Project W-320, 241-C-106 sluicing electrical calculations, Volume 2
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bailey, J.W.
1998-08-07
This supporting document has been prepared to make the FDNW calculations for Project W-320, readily retrievable. These calculations are required: To determine the power requirements needed to power electrical heat tracing segments contained within three manufactured insulated tubing assemblies; To verify thermal adequacy of tubing assembly selection by others; To size the heat tracing feeder and branch circuit conductors and conduits; To size protective circuit breaker and fuses; and To accomplish thermal design for two electrical heat tracing segments: One at C-106 tank riser 7 (CCTV) and one at the exhaust hatchway (condensate drain). Contents include: C-Farm electrical heat tracing;more » Cable ampacity, lighting, conduit fill and voltage drop; and Control circuit sizing and voltage drop analysis for the seismic shutdown system.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kuz'micheva, K. I.; Merzlyakov, A. S.; Fokin, G. G.
2013-05-15
The reasons for circuit-breaker failures during repeated disconnection of 500 - 750 kV overhead lines with shunt reactors in a cycle of unsuccessful three-phase automatic reconnection (TARC) are analyzed. Recommendations are made for increasing the operating reliability of power transmission lines with shunt reactors when there is unsuccessful reconnection.
Frequency behavior of the residual current devices
NASA Astrophysics Data System (ADS)
Erdei, Z.; Horgos, M.; Lung, C.; Pop-Vadean, A.; Muresan, R.
2017-01-01
This paper presents an experimental investigation into the operating characteristic of residual current devices when in presence of a residual current at a frequency of 60Hz. In order to protect persons and equipment effectively the residual current devices are made to be very sensitive to the ground fault current or the touch current. Because of their high sensitivity the residual current circuit breakers are prone to tripping under no-fault conditions.
Speckle measurements of density and temperature profiles in a model gas circuit breaker
NASA Astrophysics Data System (ADS)
Stoller, P. C.; Panousis, E.; Carstensen, J.; Doiron, C. B.; Färber, R.
2015-01-01
Speckle imaging was used to measure the density and temperature distribution in the arc zone of a model high voltage circuit breaker during the high current phase and under conditions simulating those present during current-zero crossings (current-zero-like arc); the arc was stabilized by a transonic, axial flow of synthetic air. A single probe beam was used; thus, accurate reconstruction was only possible for axially symmetric gas flows and arc channels. The displacement of speckles with respect to a reference image was converted to a line-of-sight integrated deflection angle, which was in turn converted into an axially symmetric refractive index distribution using a multistep process that made use of the inverse Radon transform. The Gladstone-Dale relation, which gives the index of refraction as a function of density, was extended to high temperatures by taking into account dissociation and ionization processes. The temperature and density were determined uniquely by assuming that the pressure distribution in the case of cold gas flow (in the absence of an arc) is not modified significantly by the arc. The electric conductivity distribution was calculated from the temperature profile and compared to measurements of the arc voltage and to previous results published in the literature for similar experimental conditions.
Development of 72/84kV Dry Air Insulated Dead Tank Type VCB
NASA Astrophysics Data System (ADS)
Saito, Hitoshi; Nagatake, Kazuhiro; Komatsu, Hideki; Takeshita, Yukihiro; Matsui, Yoshihiko; Katsumata, Kiyohito; Sakaki, Masayuki
As a circuit breaker for over 84kV, SF6 gas circuit breaker (GCB) has been used for a long time, in virtue of its excellent characteristics as arc extinction and insulating medium. Although, SF6 gas has very high global warming potential (GWP) of 23,900, and it was designated to regulation object in COP3 in Kyoto in 1997. A lot of efforts have been done to reduce the amount of SF6 gas usage and emission from conventional equipments. On the other hand, SF6 gas free equipment has been researching and one strong candidate is air-insulated type switchgears with vacuum interrupters. In last few years, air-insulated switchgears, which include GIS, Cubicle type GIS (C-GIS) and dead tank type VCB, have been developed in succession. So far, we have already more than three years operation record for the air-insulated dead tank type VCB, and over 100 units is in-service in power systems. Recently, VCB technology, that is essential for SF6 gas-free equipments, has been advanced in the field of high-voltage, large current interruption and environment-conscious design. In this paper, the advanced dead tank type VCB and its technology is descried.
NASA Astrophysics Data System (ADS)
Mo, Yongpeng; Shi, Zongqian; Jia, Shenli; Wang, Lijun
2015-02-01
The inter-contact region of vacuum circuit breakers is filled with residual plasma at the moment when the current is zero after the burning of metal vapor arc. The residual plasma forms an ion sheath in front of the post-arc cathode. The sheath then expands towards the post-arc anode under the influence of a transient recovery voltage. In this study, a one-dimensional particle-in-cell model is developed to investigate the post-arc sheath expansion. The influence of ion and electron temperatures on the decrease in local plasma density at the post-arc cathode side and post-arc anode side is discussed. When the decay in the local plasma density develops from the cathode and anode sides into the high-density region and merges, the overall plasma density in the inter-contact region begins to decrease. Meanwhile, the ion sheath begins to expand faster. Furthermore, the theory of ion rarefaction wave only explains quantitatively the decrease in the overall plasma density at relatively low ion temperatures. With the increase of ion temperature to certain extent, another possible reason for the decrease in the overall plasma density is proposed and results from the more active thermal diffusion of plasma.
Solid State Technology Branch of NASA Lewis Research Center
NASA Technical Reports Server (NTRS)
1992-01-01
A collection of papers written by the members of the Solid State Technology Branch of NASA LeRC from Jun. 1991 - Jun. 1992 is presented. A range of topics relating to superconductivity, Monolithic Microwave Circuits (MMIC's), coplanar waveguides, and material characterization is covered.
Solid-state switch increases switching speed
NASA Technical Reports Server (NTRS)
Mcgowan, G. F.
1966-01-01
Solid state switch for commutating capacitors in an RC commutated network increases switching speed and extends the filtering or commutating frequency spectrum well into the kilocycle region. The switch is equivalent to the standard double- pole double-throw /DPDT/ relay and is driven from digital micrologic circuits.
Li, Huili; Lv, Tian; Li, Ning; Yao, Yao; Liu, Kai; Chen, Tao
2017-11-30
Hydrogels with high ionic conductivity consisting of a cross-linked polymer network swollen in water are very promising to be used as an electrolyte for all-solid-state supercapacitors. However, there are rather few flexible supercapacitors using ionic conducting hydrogel electrolytes reported to date. In this work, highly flexible and ionic conducting polyacrylamide hydrogels were synthesized through a simple approach. On using the ionic hydrogels as the electrolyte, the resulting supercapacitors not only exhibited a high specific capacitance but also showed a long self-discharge time (over 10 hours to the half of original open-circuit voltage) and a low leakage current. These newly-developed all-solid-state supercapacitors can be bent, knot, and kneaded for 5000 cycles without performance decay, suggesting excellent flexibility and mechanical stability. These all-solid-state supercapacitors can also be easily tailored into strip-like supercapacitors without a short circuit, which provides an efficient approach to fabricate wearable energy storage devices.
Hybrid quantum processors: molecular ensembles as quantum memory for solid state circuits.
Rabl, P; DeMille, D; Doyle, J M; Lukin, M D; Schoelkopf, R J; Zoller, P
2006-07-21
We investigate a hybrid quantum circuit where ensembles of cold polar molecules serve as long-lived quantum memories and optical interfaces for solid state quantum processors. The quantum memory realized by collective spin states (ensemble qubit) is coupled to a high-Q stripline cavity via microwave Raman processes. We show that, for convenient trap-surface distances of a few microm, strong coupling between the cavity and ensemble qubit can be achieved. We discuss basic quantum information protocols, including a swap from the cavity photon bus to the molecular quantum memory, and a deterministic two qubit gate. Finally, we investigate coherence properties of molecular ensemble quantum bits.
16 CFR 1211.4 - General requirements for protection against risk of injury.
Code of Federal Regulations, 2014 CFR
2014-01-01
... closes. (c) An electronic or solid-state circuit that performs a back-up, limiting, or other function... circuits, shall comply with the requirements in the Standard for Safety for Tests for Safety-Related...
16 CFR 1211.4 - General requirements for protection against risk of injury.
Code of Federal Regulations, 2011 CFR
2011-01-01
... closes. (c) An electronic or solid-state circuit that performs a back-up, limiting, or other function... circuits, shall comply with the requirements in the Standard for Safety for Tests for Safety-Related...
16 CFR 1211.4 - General requirements for protection against risk of injury.
Code of Federal Regulations, 2010 CFR
2010-01-01
... closes. (c) An electronic or solid-state circuit that performs a back-up, limiting, or other function... circuits, shall comply with the requirements in the Standard for Safety for Tests for Safety-Related...
16 CFR 1211.4 - General requirements for protection against risk of injury.
Code of Federal Regulations, 2012 CFR
2012-01-01
... closes. (c) An electronic or solid-state circuit that performs a back-up, limiting, or other function... circuits, shall comply with the requirements in the Standard for Safety for Tests for Safety-Related...
1983-08-01
N ENTER UNIT NURSER YOU ARE USING FOR THE DATA TAPE 11 FIGURE A-20 A-15 PMOMR TO P"IN? PROCES: DATA SHEET - DECOMED PIC CONTRL INSERT DATA TAPE IN...EXCHANGE/COOLER 70 CONTROL PANEL1 ACTUATORPFEELER 71 TV MONITOR 2 MOTOR 72 CART TOP3 PUMP 73 CIRCUIT BREAKER 4 VALVE 74 5 BELT 75 LIGHT6 SEAL 76 MIRAN 807
Addressing Circuitous Currents MVDC Power Systems Protection
2017-12-31
load . The converter modules are current-controlled buck converters. They are being controlled to provide a no - load voltage of 155V at their outputs...PAGE Form Approved 0MB No . 0704-0188 The public reporting burden for this collection of information is estimated to average 1 hour per response...distribution is unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT The work investigates Z-source breakers in multi-zone systems with current to the load through
16 CFR § 1211.4 - General requirements for protection against risk of injury.
Code of Federal Regulations, 2013 CFR
2013-01-01
... closes. (c) An electronic or solid-state circuit that performs a back-up, limiting, or other function... circuits, shall comply with the requirements in the Standard for Safety for Tests for Safety-Related...
Solid State Technology Branch of NASA Lewis Research Center: Fifth Annual Digest
NASA Technical Reports Server (NTRS)
1993-01-01
The digest is a collection of papers written by the members of the Solid State Technology Branch of NASA Lewis Research Center from June 1992-June 1993. The papers cover a range of topics relating to superconductivity, monolithic microwave integrated circuits (MMIC's), coplanar waveguide, and material characterization.
Technique for improving solid state mosaic images
NASA Technical Reports Server (NTRS)
Saboe, J. M.
1969-01-01
Method identifies and corrects mosaic image faults in solid state visual displays and opto-electronic presentation systems. Composite video signals containing faults due to defective sensing elements are corrected by a memory unit that contains the stored fault pattern and supplies the appropriate fault word to the blanking circuit.
NASA Technical Reports Server (NTRS)
Fox, D. A.; Fullemann, J. S.
1980-01-01
Compact, solid state, electric-power controller switches power on and off at remote load, limits current drawn by load, and shuts off (with 2- to 3- second trip time) in case of short circuit. Lightweight efficient hybrid unit operates at 28 volts dc and at maximum currents of from 3 to 2 amperes.
DOT National Transportation Integrated Search
1977-12-01
Consideration is given to the properties of solid-state circuits, miniature relays and large gravity-operated relays when applied to control systems for grade crossings equipped with train-activated motorist warnings. Factors discussed include origin...
Environmental performance evaluation of an advanced-design solid-state television camera
NASA Technical Reports Server (NTRS)
1979-01-01
The development of an advanced-design black-and-white solid-state television camera which can survive exposure to space environmental conditions was undertaken. A 380 x 488 element buried-channel CCD is utilized as the image sensor to ensure compatibility with 525-line transmission and display equipment. Specific camera design approaches selected for study and analysis included: (1) component and circuit sensitivity to temperature; (2) circuit board thermal and mechanical design; and (3) CCD temperature control. Preferred approaches were determined and integrated into the final design for two deliverable solid-state TV cameras. One of these cameras was subjected to environmental tests to determine stress limits for exposure to vibration, shock, acceleration, and temperature-vacuum conditions. These tests indicate performance at the design goal limits can be achieved for most of the specified conditions.
Jha, Kamal N.
1999-01-01
An arc fault detection system for use on ungrounded or high-resistance-grounded power distribution systems is provided which can be retrofitted outside electrical switchboard circuits having limited space constraints. The system includes a differential current relay that senses a current differential between current flowing from secondary windings located in a current transformer coupled to a power supply side of a switchboard, and a total current induced in secondary windings coupled to a load side of the switchboard. When such a current differential is experienced, a current travels through a operating coil of the differential current relay, which in turn opens an upstream circuit breaker located between the switchboard and a power supply to remove the supply of power to the switchboard.
NASA Astrophysics Data System (ADS)
Liu, Yingyi; Yuan, Haiwen; Zhang, Qingjie; Chen, Degui; Yuan, Haibin
The dynamic characteristics are the key issues in the optimum design of a permanent magnetic actuator (PMA). A new approach to forecast the dynamic characteristics of the multilink PMA is proposed. By carrying out further developments of ADAMS and ANSOFT, a mathematic calculation model describing the coupling of mechanical movement, electric circuit and magnetic field considering eddy current effect, is constructed. With this model, the dynamic characteristics of the multilink PMA are calculated and compared with the experimental results. Factors that affect the opening time of the multilink PMA are analyzed with the model as well. The method is capable of providing a reference for the design of the PMA.
NASA Astrophysics Data System (ADS)
Naito, Yuji; Shimizu, Iwao; Yamaguchi, Iwao; Kaiho, Katsuyuki; Yanabu, Satoru
Using high temperature superconductor, a Superconducting Fault Current Limiter (SFCL) was made and tested. Superconductor and vacuum interrupter as commutation switch are connected in parallel with bypass coil. When a fault occurs and the excessive current flows, superconductor is first quenched and the current is transferred to bypass coil because on voltage drop of superconductor. At the same time, since magnetic field is generated by current which flows in bypass coil, commutation switch is immediately driven by electromagnetic repulsion plate connected to driving rod of vacuum interrupter, and superconductor is separated from this circuit. Using the testing model, we could separate the superconductor from a circuit due to movement of vacuum interrupter within half-cycle current and transfer all current to bypass coil. Since operation of a commutation switch is included in current limiting operation of this testing model, it is one of helpful circuit of development of SFCL in the future. Moreover, since it can make the consumed energy of superconductor small during fault state due to realization of high-speed switch with simple composition, the burden of superconductor is reduced compared with conventional resistive type SFCL and it is considered that the flexibility of a SFCL design increases. Cooperation with a circuit breaker was also considered, the trial calculation of a parameter and energy of operation is conducted and discussion in the case of installing the SFCL to electric power system is made.
Software Testbed for Developing and Evaluating Integrated Autonomous Subsystems
NASA Technical Reports Server (NTRS)
Ong, James; Remolina, Emilio; Prompt, Axel; Robinson, Peter; Sweet, Adam; Nishikawa, David
2015-01-01
To implement fault tolerant autonomy in future space systems, it will be necessary to integrate planning, adaptive control, and state estimation subsystems. However, integrating these subsystems is difficult, time-consuming, and error-prone. This paper describes Intelliface/ADAPT, a software testbed that helps researchers develop and test alternative strategies for integrating planning, execution, and diagnosis subsystems more quickly and easily. The testbed's architecture, graphical data displays, and implementations of the integrated subsystems support easy plug and play of alternate components to support research and development in fault-tolerant control of autonomous vehicles and operations support systems. Intelliface/ADAPT controls NASA's Advanced Diagnostics and Prognostics Testbed (ADAPT), which comprises batteries, electrical loads (fans, pumps, and lights), relays, circuit breakers, invertors, and sensors. During plan execution, an experimentor can inject faults into the ADAPT testbed by tripping circuit breakers, changing fan speed settings, and closing valves to restrict fluid flow. The diagnostic subsystem, based on NASA's Hybrid Diagnosis Engine (HyDE), detects and isolates these faults to determine the new state of the plant, ADAPT. Intelliface/ADAPT then updates its model of the ADAPT system's resources and determines whether the current plan can be executed using the reduced resources. If not, the planning subsystem generates a new plan that reschedules tasks, reconfigures ADAPT, and reassigns the use of ADAPT resources as needed to work around the fault. The resource model, planning domain model, and planning goals are expressed using NASA's Action Notation Modeling Language (ANML). Parts of the ANML model are generated automatically, and other parts are constructed by hand using the Planning Model Integrated Development Environment, a visual Eclipse-based IDE that accelerates ANML model development. Because native ANML planners are currently under development and not yet sufficiently capable, the ANML model is translated into the New Domain Definition Language (NDDL) and sent to NASA's EUROPA planning system for plan generation. The adaptive controller executes the new plan, using augmented, hierarchical finite state machines to select and sequence actions based on the state of the ADAPT system. Real-time sensor data, commands, and plans are displayed in information-dense arrays of timelines and graphs that zoom and scroll in unison. A dynamic schematic display uses color to show the real-time fault state and utilization of the system components and resources. An execution manager coordinates the activities of the other subsystems. The subsystems are integrated using the Internet Communications Engine (ICE). an object-oriented toolkit for building distributed applications.
Implementation and initial test result of a prototype solid state modulator for pulsed magnetron
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dake, Vishal; Mangalvedekar, H.A., E-mail: vishaldake90@gmail.com; Tillu, Abhijit
2014-07-01
A solid-state modulator rated for 50 kV, 120A, 4μs and 250 Hz has been designed. The discharging circuit of the modulator is being tested at ∼ 33 kV, 40-80A, at a maximum pulse repetition rate of 30 pps. The paper discusses development and testing of prototype discharging circuit on resistive load and magnetron. The technique used for measurement of pulse transformer leakage inductance, distributed capacitance and stray primary circuit series inductance will also be discussed in detail. It is necessary to have Energy Storage Capacitors with low ESL for these applications (ESL < 40 nH). The method used for evaluatingmore » the ESL of locally available metalized polypropylene capacitors will also be presented. (author)« less
32. TYPICAL BRYANT ITEMS FROM THE 1930S; TOP ROW LEFT ...
32. TYPICAL BRYANT ITEMS FROM THE 1930S; TOP ROW LEFT TO RIGHT: PORCELAIN CASED SWITCH, ROTARY SWITCH, SHORTING PLUG TO BYPASS FUSE; SECOND ROW: BRASS INCANDESCENT LAMP SURFACE RECEPTACLE, INCANDESCENT LAMPHOLDER WITH ADAPTER FOR GLASS GLOBE; THIRD ROW: PORCELAIN BASE ROTARY SWITCH, APPLIANCE BREAKER WITH COVER REMOVED, APPLIANCE BREAKER - Bryant Electric Company, 1421 State Street, Bridgeport, Fairfield County, CT
Studies and comparison of currently utilized models for ablation in Electrothermal-chemical guns
NASA Astrophysics Data System (ADS)
Jia, Shenli; Li, Rui; Li, Xingwen
2009-10-01
Wall ablation is a key process taking place in the capillary plasma generator in Electrothermal-Chemical (ETC) guns, whose characteristic directly decides the generator's performance. In the present article, this ablation process is theoretically studied. Currently widely used mathematical models designed to describe such process are analyzed and compared, including a recently developed kinetic model which takes into account the unsteady state in plasma-wall transition region by dividing it into two sub-layers, a Knudsen layer and a collision dominated non-equilibrium Hydrodynamic layer, a model based on Langmuir Law, as well as a simplified model widely used in arc-wall interaction process in circuit breakers, which assumes a proportional factor and an ablation enthalpy obtained empirically. Bulk plasma state and parameters are assumed to be consistent while analyzing and comparing each model, in order to take into consideration only the difference caused by model itself. Finally ablation rate is calculated in each method respectively and differences are discussed.
NASA Technical Reports Server (NTRS)
Fox, D. A.
1977-01-01
Solid-state relay (SSR), containing multinode control logic, is operated as normally open, normally closed, or latched. Moreover several can be paralleled to form two-pole or double-throw relays. Versatile unit ends need to design custom control circuit for every relay application. Technique can be extended to incorporate selectable time delay, on operation or release, or pulsed output.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mo, Yongpeng; Shi, Zongqian; Jia, Shenli
2015-02-15
The inter-contact region of vacuum circuit breakers is filled with residual plasma at the moment when the current is zero after the burning of metal vapor arc. The residual plasma forms an ion sheath in front of the post-arc cathode. The sheath then expands towards the post-arc anode under the influence of a transient recovery voltage. In this study, a one-dimensional particle-in-cell model is developed to investigate the post-arc sheath expansion. The influence of ion and electron temperatures on the decrease in local plasma density at the post-arc cathode side and post-arc anode side is discussed. When the decay inmore » the local plasma density develops from the cathode and anode sides into the high-density region and merges, the overall plasma density in the inter-contact region begins to decrease. Meanwhile, the ion sheath begins to expand faster. Furthermore, the theory of ion rarefaction wave only explains quantitatively the decrease in the overall plasma density at relatively low ion temperatures. With the increase of ion temperature to certain extent, another possible reason for the decrease in the overall plasma density is proposed and results from the more active thermal diffusion of plasma.« less
Fundamental Insulation Characteristics of Air, N2, CO2, N2/O2 and SF6/N2 Mixed Gases
NASA Astrophysics Data System (ADS)
Rokunohe, Toshiaki; Yagihashi, Yoshitaka; Endo, Fumihiro; Oomori, Takashi
SF6 gas has excellent dielectric strength and interruption performance. For these reasons, it has been widely used for gas insulated switchgear (GIS). However, use of SF6 gas has become regulated under agreements set at the 1997 COP3. Presently, development of a gas circuit breaker (GCB) using CO2 gas and development of a high voltage vacuum circuit breaker (VCB) are being pursued. GIS consists of disconnectors (DS), earthing switches (ES) and buses in addition to GCB. Since the interruption performance is not an important requirement for DS, ES and BUS, use of a gas with high dielectric strength is better than use of a gas with good interruption performance. Air and N2 are not greenhouse gases, and their dielectric strengths are higher than those of other SF6 alternative gases, but only about one-third of the dielectric strength of SF6 gas. This paper deals with a suitable insulation gas which has no greenhouse effect as an SF6 alternative gas. The N2/O2 mixed gas was investigated by changing the ratio of O2. Moreover, the effect of an insulation coating was investigated and compared with the dielectric strength of SF6/N2 mixed gas. The dielectric strength of air under the coating condition was equal to that of 10%SF6/N2 mixed gas.
Hybrid integrated biological-solid-state system powered with adenosine triphosphate.
Roseman, Jared M; Lin, Jianxun; Ramakrishnan, Siddharth; Rosenstein, Jacob K; Shepard, Kenneth L
2015-12-07
There is enormous potential in combining the capabilities of the biological and the solid state to create hybrid engineered systems. While there have been recent efforts to harness power from naturally occurring potentials in living systems in plants and animals to power complementary metal-oxide-semiconductor integrated circuits, here we report the first successful effort to isolate the energetics of an electrogenic ion pump in an engineered in vitro environment to power such an artificial system. An integrated circuit is powered by adenosine triphosphate through the action of Na(+)/K(+) adenosine triphosphatases in an integrated in vitro lipid bilayer membrane. The ion pumps (active in the membrane at numbers exceeding 2 × 10(6) mm(-2)) are able to sustain a short-circuit current of 32.6 pA mm(-2) and an open-circuit voltage of 78 mV, providing for a maximum power transfer of 1.27 pW mm(-2) from a single bilayer. Two series-stacked bilayers provide a voltage sufficient to operate an integrated circuit with a conversion efficiency of chemical to electrical energy of 14.9%.
The Generating Mechanism of Non-Sustained Disruptive Discharges in Vacuum Interrupters
NASA Astrophysics Data System (ADS)
Hara, Daisuke; Taki, Masayuki; Tanaka, Hitoshi; Okawa, Mikio; Yanabu, Satoru
To develop vacuum circuit breaker (VCB) for higher voltage application, it may be important to understand generating mechanism and its influence of non-sustained disruptive discharges (NSDD) to the systems. So, we carried out the tests using equivalent testing circuit and observed the contacts after testing, For the test, by using commercial vacuum circuit interrupters, AC voltages of 50Hz was applied between contacts for 4 seconds after current interruption, and measured generating frequencies of NSDD vs. the voltages and vs. currents. Typical contact material used in the commercial switching equipment, such as AgWC, CuW, CuCr were tested and compared. Then CuCr's of different composition and manufacturing process are investigated. And CuCr-50 (manufactured by melting process) showed the best performance in all tests. We point out that surface condition may affect the generation of NSDD and also conditioning effect is very important.
NASA Technical Reports Server (NTRS)
1976-01-01
The design, fabrication, and tests of a solid state television camera using a new charge-coupled imaging device are reported. An RCA charge-coupled device arranged in a 512 by 320 format and directly compatible with EIA format standards was the sensor selected. This is a three-phase, sealed surface-channel array that has 163,840 sensor elements, which employs a vertical frame transfer system for image readout. Included are test results of the complete camera system, circuit description and changes to such circuits as a result of integration and test, maintenance and operation section, recommendations to improve the camera system, and a complete set of electrical and mechanical drawing sketches.
Means for limiting and ameliorating electrode shorting
Van Konynenburg, Richard A.; Farmer, Joseph C.
1999-01-01
A fuse and filter arrangement for limiting and ameliorating electrode shorting in capacitive deionization water purification systems utilizing carbon aerogel, for example. This arrangement limits and ameliorates the effects of conducting particles or debonded carbon aerogel in shorting the electrodes of a system such as a capacitive deionization water purification system. This is important because of the small interelectrode spacing and the finite possibility of debonding or fragmentation of carbon aerogel in a large system. The fuse and filter arrangement electrically protect the entire system from shutting down if a single pair of electrodes is shorted and mechanically prevents a conducting particle from migrating through the electrode stack, shorting a series of electrode pairs in sequence. It also limits the amount of energy released in a shorting event. The arrangement consists of a set of circuit breakers or fuses with one fuse or breaker in the power line connected to one electrode of each electrode pair and a set of screens of filters in the water flow channels between each set of electrode pairs.
NASA Astrophysics Data System (ADS)
Bazanov, A. A.; Ivanovskii, A. V.; Panov, A. I.; Samodolov, A. V.; Sokolov, S. S.; Shaidullin, V. Sh.
2017-06-01
We report on the results of the computer simulation of the operation of magnetodynamic break switches used as the second stage of current pulse formation in magnetic explosion generators. The simulation was carried out under the conditions when the magnetic field energy density on the surface of the switching conductor as a function of the current through it was close to but still did not exceed the critical value typical of the beginning of electric explosion. In the computational model, we used the parameters of experimentally tested sample of a coil magnetic explosion generator that can store energy of up to 2.7 MJ in the inductive storage circuit and equipped with a primary explosion stage of the current pulse formation. It has been shown that the choice of the switching conductor material, as well as its elastoplastic properties, considerably affects the breaker speed. Comparative results of computer simulation for copper and aluminum have been considered.
Jha, K.N.
1999-05-18
An arc fault detection system for use on ungrounded or high-resistance-grounded power distribution systems is provided which can be retrofitted outside electrical switchboard circuits having limited space constraints. The system includes a differential current relay that senses a current differential between current flowing from secondary windings located in a current transformer coupled to a power supply side of a switchboard, and a total current induced in secondary windings coupled to a load side of the switchboard. When such a current differential is experienced, a current travels through a operating coil of the differential current relay, which in turn opens an upstream circuit breaker located between the switchboard and a power supply to remove the supply of power to the switchboard. 1 fig.
1987-01-07
Excimer-Laser Projection Lithography 38 4.5 Observation of Millimeter-Wave Oscillations from Resonant- Tunneling Diodes and Some Theroretical...and SIMOX Circuits 32 4-1 Resonant Tunneling Diode Parameters 41 XI INTRODUCTION 1. SOLID STATE DEVICE RESEARCH Optoelectronic switches have...radiation and reflective optics. Oscillation frequencies as high as 56 GHz have been observed from resonant- tunneling double- barrier diodes. Recent
18. Station Service Control and Motor Control Center #2, view ...
18. Station Service Control and Motor Control Center #2, view to the northeast. Note the circuit breaker switch on cart in left corner of photograph. This switch is part of the motor control center which has been temporarily removed from the slot marked with a tag that is visible at lower left end of control center. - Washington Water Power Clark Fork River Noxon Rapids Hydroelectric Development, Powerhouse, South bank of Clark Fork River at Noxon Rapids, Noxon, Sanders County, MT
Contact dynamics recording and analysis system using an optical fiber sensor approach
NASA Astrophysics Data System (ADS)
Anghel, F.; Pavelescu, D.; Grattan, K. T. V.; Palmer, A. W.
1997-09-01
A contact dynamics recording and analysis system configured using an optical fiber sensor has been developed having been designed with a particular application to the accurate and time-varying description of moving contact operating during electrical arc breaking, in an experimental platform simulating the operation of a vacuum circuit breaker. The system utilizes dynamic displacement measurement and data recording and a post-process data analysis to reveal the dynamic speed and acceleration data of the equipment.
17. VIEW OF ANCHOR BRIDGE NUMBER 310 LOOKING EAST ALONG ...
17. VIEW OF ANCHOR BRIDGE NUMBER 310 LOOKING EAST ALONG THE MAIN LINE TRACK LOCATED TO THE NORTH OF THE COS COB POWER PLANT. ANCHOR BRIDGES LOCATED AT TWO MILE INTERVALS WITHSTAND CATENARY TENSION AND PROVIDE A PLATFORM FOR MOUNTING OIL FILLED CIRCUIT BREAKERS, LIGHTNING ARRESTORS AND OTHER ELECTRICAL EQUIPMENT. THE ROOF OF THE LOAD DISPATCHER'S TOWER CAN BE SEEN DIRECTLY BEHIND THE RIGHT SIDE OF THE BRIDGE. - New York, New Haven & Hartford Railroad, Cos Cob Power Plant, Sound Shore Drive, Greenwich, Fairfield County, CT
NASA Astrophysics Data System (ADS)
Lisnyak, M.; Pipa, A. V.; Gorchakov, S.; Iseni, S.; Franke, St.; Khapour, A.; Methling, R.; Weltmann, K.-D.
2015-09-01
Spectroscopic investigations of free-burning vacuum arcs in diffuse mode with CuCr electrodes are presented. The experimental conditions of the investigated arc correspond to the typical system for vacuum circuit breakers. Spectra of six species Cu I, Cu II, Cu III, Cr I, Cr II, and Cr III have been analyzed in the wavelength range 350-810 nm. The axial intensity distributions were found to be strongly dependent on the ionization stage of radiating species. Emission distributions of Cr II and Cu II can be distinguished as well as the distributions of Cr III and Cu III. Information on the axial distribution was used to identify the spectra and for identification of overlapping spectral lines. The overview spectra and some spectral windows recorded with high resolution are presented. Analysis of axial distributions of emitted light, which originates from different ionization states, is presented and discussed.
NASA Astrophysics Data System (ADS)
Boenig, Heinrich J.; Bogdan, Ferenc; Morris, Gary C.; Ferner, James A.; Schneider-Muntau, Hans J.; Rumrill, Ronald H.; Rumrill, Ronald S.
1994-07-01
Four highly stabilized, steady-state, 10 MW power supplies have been installed at the National High Magnetic Field Laboratory in Tallahassee, FL. Each supply consists of a 12.5 kV vacuum circuit breaker, two three-winding, step-down transformers, a 24-pulse rectifier with interphase reactors and freewheeling diodes, and a passive and an active filter. Two different transformer tap settings allow dc supply output voltages of 400 and 500 V. The rated current of a supply is 17 kA and each supply has a one hour overload capability of 20 kA. The power supply output bus system, including a reversing switch at the input and 2 x 16 disconnect switches at the output, connects each supply to 16 different magnet cells. The design of the power supply is described and preliminary test results with a supply feeding a 10 MW resistive load are presented.
Plastic-Sealed Hybrid Power Circuit Package
NASA Technical Reports Server (NTRS)
Miller, W. N.; Gray, O. E.
1983-01-01
Proposed design for hybrid high-voltage power-circuit package uses molded plastic for hermetic sealing instead of glass-to-metal seal. New package used to house high-voltage regulators and solid-state switches for applications in aircraft, electric automobiles, industrial equipment, satellites, solarcell arrays, and other equipment in extreme environments.
Fault detection monitor circuit provides ''self-heal capability'' in electronic modules - A concept
NASA Technical Reports Server (NTRS)
Kennedy, J. J.
1970-01-01
Self-checking technique detects defective solid state modules used in electronic test and checkout instrumentation. A ten bit register provides failure monitor and indication for 1023 comparator circuits, and the automatic fault-isolation capability permits the electronic subsystems to be repaired by replacing the defective module.
Solid State Technology Branch of NASA Lewis Research Center: Fifth Annual Digest
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1993-08-01
The digest is a collection of papers written by the members of the Solid State Technology Branch of NASA Lewis Research Center from June 1992-June 1993. The papers cover a range of topics relating to superconductivity, monolithic microwave integrated circuits (MMIC`s), coplanar waveguide, and material characterization. Individual papers are abstracted separately on the data base.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Meng, Ling-Jian
A gamma ray detector apparatus comprises a solid state detector that includes a plurality of anode pixels and at least one cathode. The solid state detector is configured for receiving gamma rays during an interaction and inducing a signal in an anode pixel and in a cathode. An anode pixel readout circuit is coupled to the plurality of anode pixels and is configured to read out and process the induced signal in the anode pixel and provide triggering and addressing information. A waveform sampling circuit is coupled to the at least one cathode and configured to read out and processmore » the induced signal in the cathode and determine energy of the interaction, timing of the interaction, and depth of interaction.« less
Geiger-Mode Avalanche Photodiode Arrays Integrated to All-Digital CMOS Circuits.
Aull, Brian
2016-04-08
This article reviews MIT Lincoln Laboratory's work over the past 20 years to develop photon-sensitive image sensors based on arrays of silicon Geiger-mode avalanche photodiodes. Integration of these detectors to all-digital CMOS readout circuits enable exquisitely sensitive solid-state imagers for lidar, wavefront sensing, and passive imaging.
Series resonance inverter with triggered vacuum gaps
NASA Astrophysics Data System (ADS)
Damstra, Geert C.; Zhang, X.
1994-05-01
Series resonance inverters based on semi-conductor switching elements are well-known and have a wide range of application, mainly for lower voltages. For high voltage application many switching elements have to be put in series to obtain sufficient blocking voltage. Voltage grinding and multiple gate control elements are needed. There is much experience with the triggered vacuum gaps as high voltage/high current single shot elements, for example in reignition circuits for synthetic circuit breaker tests. These elements have a blocking voltage of 50 - 100 kV and are triggerable by a light fiber control device. A prototype inverter has been developed that generates 0.1 Hz, 30 kV AC voltages with a flat top for tests on cables and capacitors of many micro farads fed from a low voltage supply of about 600 V. Only two TVG elements are needed to switch the resonant circuit alternatively on the positive or negative supply. The resonant circuit itself consists of the capacitance of the testobject and a high quality inductor that determines the frequency and the peak current of the voltage reversing process.
One-step generation of continuous-variable quadripartite cluster states in a circuit QED system
NASA Astrophysics Data System (ADS)
Yang, Zhi-peng; Li, Zhen; Ma, Sheng-li; Li, Fu-li
2017-07-01
We propose a dissipative scheme for one-step generation of continuous-variable quadripartite cluster states in a circuit QED setup consisting of four superconducting coplanar waveguide resonators and a gap-tunable superconducting flux qubit. With external driving fields to adjust the desired qubit-resonator and resonator-resonator interactions, we show that continuous-variable quadripartite cluster states of the four resonators can be generated with the assistance of energy relaxation of the qubit. By comparison with the previous proposals, the distinct advantage of our scheme is that only one step of quantum operation is needed to realize the quantum state engineering. This makes our scheme simpler and more feasible in experiment. Our result may have useful application for implementing quantum computation in solid-state circuit QED systems.
A 32-GHz solid-state power amplifier for deep space communications
NASA Technical Reports Server (NTRS)
Wamhof, P. D.; Rascoe, D. L.; Lee, K. A.; Lansing, F. S.
1994-01-01
A 1.5-W solid-state power amplifier (SSPA) has been demonstrated as part of an effort to develop and evaluate state-of-the-art transmitter and receiver components at 32 and 35 GHz for future deep space missions. Output power and efficiency measurements for a monolithic millimeter-wave integrated circuit (MMIC)-based SSPA are reported. Technical design details for the various modules and a thermal analysis are discussed, as well as future plans.
High-efficiency solid state power amplifier
NASA Technical Reports Server (NTRS)
Wallis, Robert E. (Inventor); Cheng, Sheng (Inventor)
2005-01-01
A high-efficiency solid state power amplifier (SSPA) for specific use in a spacecraft is provided. The SSPA has a mass of less than 850 g and includes two different X-band power amplifier sections, i.e., a lumped power amplifier with a single 11-W output and a distributed power amplifier with eight 2.75-W outputs. These two amplifier sections provide output power that is scalable from 11 to 15 watts without major design changes. Five different hybrid microcircuits, including high-efficiency Heterostructure Field Effect Transistor (HFET) amplifiers and Monolithic Microwave Integrated Circuit (MMIC) phase shifters have been developed for use within the SSPA. A highly efficient packaging approach enables the integration of a large number of hybrid circuits into the SSPA.
Vaporization of a solid surface in an ambient gas
NASA Astrophysics Data System (ADS)
Benilov, M. S.; Jacobsson, S.; Kaddani, A.; Zahrai, S.
2001-07-01
The net flux of vapour from a solid surface in an ambient gas is analysed with the aim to estimate the effect of vaporization cooling on the energy balance of an arc cathode under conditions typical for a high-power current breaker. If the ratio of the equilibrium vapour pressure pv to the ambient pressure p∞ is smaller than unity, the removal of vapour from the surface is due to diffusion into the bulk of the gas. As a consequence, the net flux of the vapour from the surface is much smaller than the emitted flux. An estimate of the diffusion rate under conditions typical for a high-power current breaker indicates that vaporization cooling plays a minor role in the energy balance of the cathode in this case. If ratio pv/p∞ is above unity, the flow of the vapour from the surface appears and the net flux is comparable to the emitted flux. A simple analytical solution has been obtained for this case, which is in a good agreement with results of the Monte Carlo modelling of preceding authors. If pv/p∞ exceeds approximately 4.5, vaporization occurs as into vacuum and the net flux is about 0.82 of the emitted flux.
NASA Astrophysics Data System (ADS)
Kim, Dong Woo; Jo, Hyun-Jun; Thogiti, Suresh; Yang, Weon Ki; Cheruku, Rajesh; Kim, Jae Hong
2017-05-01
Förster resonance energy transfer (FRET) is critical for wide spectral absorption, an increased dye loading, and photocurrent generation of dye-sensitized solar cells (DSSCs). This process consists of organic fluorescent materials (as an energy donor), and an organic dye (as an energy acceptor on TiO2 surfaces) with quasi-solid electrolyte. The judicious choice of the energy donor and acceptor facilitates a strong spectral overlap between the emission and absorption regions of the fluorescent materials and dye. This FRET process enhances the light-harvesting characteristics of quasi-solid state DSSCs. In this study, DSSCs containing different concentrations (0, 1, and 1.5 wt%) of a fluorescent material (FM) as the energy donor are investigated using FRET. The power conversion efficiency of DSSCs containing FMs in a quasi-solid electrolyte increased by 33% over a pristine cell. The optimized cell fabricated with the quasi-solid state DSSC containing 1.0 wt% FM shows a maximum efficiency of 3.38%, with a short-circuit current density ( J SC ) of 4.32 mA/cm-2, and an open-circuit voltage ( V OC ) of 0.68 V under illumination of simulated solar light (AM 1.5G, 100 mW/cm-2). [Figure not available: see fulltext.
Protection coordination of the Kennedy Space Center electric distribution network
NASA Technical Reports Server (NTRS)
1976-01-01
A computer technique is described for visualizing the coordination and protection of any existing system of devices and settings by plotting the tripping characteristics of the involved devices on a common basis. The program determines the optimum settings of a given set of protective devices and configuration in the sense of the best expected coordinated operation of these devices. Subroutines are given for simulating time versus current characteristics of the different relays, circuit breakers, and fuses in the system; coordination index computation; protection checks; plotting; and coordination optimation.
Space and time resolved representation of a vacuum arc light emission
NASA Astrophysics Data System (ADS)
Georgescu, N.; Sandolache, G.; Zoita, V.
1999-04-01
An optoelectronic multichannel detection system for the study of the visible light emission of a vacuum circuit breaker arc is described. The system consists of two multiple slit collimator assemblies coupled directly to the arc discharge chamber and an electronic detection part. The light emitted by the arc is collected by the two collimator assemblies and is transmitted through optical fibres to the electronic detection part. By using a new, simple computational method two-dimensional plots of the vacuum arc light emission at different times are obtained.
Breakdown Conditioning Chacteristics of Precision-Surface-Treatment-Electrode in Vacuum
NASA Astrophysics Data System (ADS)
Kato, Kastumi; Fukuoka, Yuji; Inagawa, Yukihiko; Saitoh, Hitoshi; Sakaki, Masayuki; Okubo, Hitoshi
Breakdown (BD) characteristics in vacuum are strongly dependent on the electrode surface condition, like the surface roughness etc. Therefore, in order to develop a high voltage vacuum circuit breaker, it is important to optimize the surface treatment process. This paper discusses about the effect of precision-surface-treatment of the electrode on breakdown conditioning characteristics under non-uniform electric field in vacuum. Experimental results reveal that the electrode surface treatment affects the conditioning process, especially the BD voltage and the BD field strength at the initial stage of the conditioning.
14. Station Control Batteries and Battery Chargers, view to the ...
14. Station Control Batteries and Battery Chargers, view to the northeast. The original battery charger is the center cabinet on the left side of photograph, with the new charger on the far left of photograph and a circuit breaker unit for the chargers is visible in the center of the photograph. The batteries are visible on three racks through the open doorway. - Washington Water Power Clark Fork River Cabinet Gorge Hydroelectric Development, Powerhouse, North Bank of Clark Fork River at Cabinet Gorge, Cabinet, Bonner County, ID
14. CONTROL PANELS, EAST SIDE, MAIN FLOOR: TO LEFT (ORIGINAL ...
14. CONTROL PANELS, EAST SIDE, MAIN FLOOR: TO LEFT (ORIGINAL EQUIPMENT): UPPER FOUR GLASS BOXES ARE OVERCURRENT PROTECTIVE RELAYS; MIDDLE FOUR GLASS BOXES CONTAIN TESTING SWITCHES; LOWER TWO BOXES ARE DG1 METERING CHART RECORDERS TO RIGHT (MODERN EQUIPMENT): UPPER FOUR BLACK BOXES ARE PROTECTIVE SERVICE RELAYS; MIDDLE FOUR BOXES CONTAIN TESTING SWITCHES; LARGE BOX BELOW HOUSES REMOTE METERING SYSTEM METAL CABINETS (LABELED L-2 & L-4) BELOW CONTAIN ORIGINAL POWER CIRCUIT BREAKERS - Bonneville Power Administration South Bank Substation, I-84, South of Bonneville Dam Powerhouse, Bonneville, Multnomah County, OR
Solid State Technology Branch of NASA Lewis Research Center
NASA Technical Reports Server (NTRS)
1991-01-01
Reprints of one year's production of research publications (June 1990 to June 1991) are presented. These are organized into three major sections: microwave circuits, both hybrid and monolithic microwave integrated circuits (MMICs); materials and device work; and superconductivity. The included papers also cover more specific topics involving waveguides, phase array antennas, dielectrics, and high temperature superconductors.
Speed-Up Techniques for Complementary Metal Oxide Semiconductor Very Large Scale Integration.
1984-12-14
The input voltage at which the two transistors are in the constant current region at the same time marks the active operating region of the inverter...decoder precharge configurations. One circuit displayed a marked enhancement in operation while the other precharged circuit displyed degraded operation due...34 IEEE Journal of Solid State Circuits, SC-18: 457-462 (October 1983). 19. Cobbold , R. Theory and Applications of Field Effect Transistors, New York: John
Heat sinking for printed circuitry
Wilson, S.K.; Richardson, G.; Pinkerton, A.L.
1984-09-11
A flat pak or other solid-state device mounted on a printed circuit board directly over a hole extends therethrough so that the bottom of the pak or device extends beyond the bottom of the circuit board. A heat sink disposed beneath the circuit board contacts the bottom of the pak or device and provides direct heat sinking thereto. Pressure may be applied to the top of the pak or device to assure good mechanical and thermal contact with the heat sink.
Hybrid Circuits with Nanofluidic Diodes and Load Capacitors
NASA Astrophysics Data System (ADS)
Ramirez, P.; Garcia-Morales, V.; Gomez, V.; Ali, M.; Nasir, S.; Ensinger, W.; Mafe, S.
2017-06-01
The chemical and physical input signals characteristic of micro- and nanofluidic devices operating in ionic solutions should eventually be translated into output electric currents and potentials that are monitored with solid-state components. This crucial step requires the design of hybrid circuits showing robust electrical coupling between ionic solutions and electronic elements. We study experimentally and theoretically the connectivity of the nanofluidic diodes in single-pore and multipore membranes with conventional capacitor systems for the cases of constant, periodic, and white-noise input potentials. The experiments demonstrate the reliable operation of these hybrid circuits over a wide range of membrane resistances, electrical capacitances, and solution p H values. The model simulations are based on empirical equations that have a solid physical basis and provide a convenient description of the electrical circuit operation. The results should contribute to advance signal transduction and processing using nanopore-based biosensors and bioelectronic interfaces.
Design and Development of a Series Switch for High Voltage in RF Heating
NASA Astrophysics Data System (ADS)
Patel, Himanshu K.; Shah, Deep; Thacker, Mauli; Shah, Atman
2013-02-01
Plasma is the fourth state of matter. To sustain plasma in its ionic form very high temperature is essential. RF heating systems are used to provide the required temperature. Arching phenomenon in these systems can cause enormous damage to the RF tube. Heavy current flows across the anode-cathode junction, which need to be suppressed in minimal time for its protection. Fast-switching circuit breakers are used to cut-off the load from the supply in cases of arching. The crowbar interrupts the connection between the high voltage power supply (HVPS) and the RF tube for a temporary period between which the series switch has to open. The crowbar shunts the current across the load but in the process leads to short circuiting the HVPS. Thus, to protect the load as well as the HVPS a series switch is necessary. This paper presents the design and development of high voltage Series Switch for the high power switching applications. Fiber optic based Optimum triggering scheme is designed and tested to restrict the time delay well within the stipulated limits. The design is well supported with the experimental results for the whole set-up along with the series switch at various voltage level before its approval for operation at 5.2 kV.
Efficient quantum circuits for one-way quantum computing.
Tanamoto, Tetsufumi; Liu, Yu-Xi; Hu, Xuedong; Nori, Franco
2009-03-13
While Ising-type interactions are ideal for implementing controlled phase flip gates in one-way quantum computing, natural interactions between solid-state qubits are most often described by either the XY or the Heisenberg models. We show an efficient way of generating cluster states directly using either the imaginary SWAP (iSWAP) gate for the XY model, or the sqrt[SWAP] gate for the Heisenberg model. Our approach thus makes one-way quantum computing more feasible for solid-state devices.
Electronics: State of the Art No. 2.
ERIC Educational Resources Information Center
Gosling, W.
1979-01-01
Reviewed is a brief history of electronics technology, from the early beginnings of vacuum devices to development of solid state devices, silicon fabrication in the use of transistors, and integrated circuits. Educational needs at the university or polytechnic level are discussed. (CS)
Wang, Jin-song; Cao, Pin-lu; Yin, Kun
2015-07-01
Environmental, economical and efficient antifoaming technology is the basis for achievement of foam drilling fluid recycling. The present study designed a novel two-stage laval mechanical foam breaker that primarily uses vacuum generated by Coanda effect and Laval principle to break foam. Numerical simulation results showed that the value and distribution of negative pressure of two-stage laval foam breaker were larger than that of the normal foam breaker. Experimental results showed that foam-breaking efficiency of two-stage laval foam breaker was higher than that of normal foam breaker, when gas-to-liquid ratio and liquid flow rate changed. The foam-breaking efficiency of normal foam breaker decreased rapidly with increasing foam stability, whereas the two-stage laval foam breaker remained unchanged. Foam base fluid would be recycled using two-stage laval foam breaker, which would reduce the foam drilling cost sharply and waste disposals that adverse by affect the environment.
Practical aspects of instrumentation system installation, volume 13
NASA Technical Reports Server (NTRS)
Borek, R. W.; Pool, A. (Editor); Sanderson, K. C. (Editor)
1981-01-01
A review of factors influencing installation of aircraft flight test instrumentation is presented. Requirements, including such factors as environment, reliability, maintainability, and system safety are discussed. The assessment of the mission profile is followed by an overview of electrical and mechanical installation factors with emphasis on shock/vibration isolation systems and standardization of the electric wiring installation, two factors often overlooked by instrumentation engineers. A discussion of installation hardware reviews the performance capabilities of wiring, connectors, fuses and circuit breakers, and a guide to proper selections is provided. The discussion of the installation is primarily concerned with the electrical wire routing, shield terminations and grounding. Also inclued are some examples of installation mistakes that could affect system accuracy. System verification procedures and special considerations such as sneak circuits, pyrotechnics, aircraft antenna patterns, and lightning strikes are discussed.
Chase, R.L.
1963-05-01
An electronic fast multiplier circuit utilizing a transistor controlled voltage divider network is presented. The multiplier includes a stepped potentiometer in which solid state or transistor switches are substituted for mechanical wipers in order to obtain electronic switching that is extremely fast as compared to the usual servo-driven mechanical wipers. While this multiplier circuit operates as an approximation and in steps to obtain a voltage that is the product of two input voltages, any desired degree of accuracy can be obtained with the proper number of increments and adjustment of parameters. (AEC)
5.8kV SiC PiN Diode for Switching of High-Efficiency Inductive Pulsed Plasma Thruster Circuits
NASA Technical Reports Server (NTRS)
Toftul, Alexandra; Polzin, Kurt A.; Hudgins, Jerry L.
2014-01-01
Inductive Pulsed Plasma Thruster (IPPT) pulse circuits, such as those needed to operate the Pulsed Inductive Thruster (PIT), are required to quickly switch capacitor banks operating at a period of µs while conducting current at levels on the order of at least 10 kA. [1,2] For all iterations of the PIT to date, spark gaps have been used to discharge the capacitor bank through an inductive coil. Recent availability of fast, high-power solid state switching devices makes it possible to consider the use of semiconductor switches in modern IPPTs. In addition, novel pre-ionization schemes have led to a reduction in discharge energy per pulse for electric thrusters of this type, relaxing the switching requirements for these thrusters. [3,4] Solid state switches offer the advantage of greater controllability and reliability, as well as decreased drive circuit dimensions and mass relative to spark gap switches. The use of solid state devices such as Integrated Gate Bipolar Transistors (IGBTs), Gate Turn-off Thyristors (GTOs) and Silicon-Controlled Rectifiers (SCRs) often involves the use of power diodes. These semiconductor devices may be connected antiparallel to the switch for protection from reverse current, or used to reduce power loss in a circuit by clamping off current ringing. In each case, higher circuit efficiency may be achieved by using a diode that is able to transition, or 'switch,' from the forward conducting state ('on' state) to the reverse blocking state ('off' state) in the shortest amount of time, thereby minimizing current ringing and switching losses. Silicon Carbide (SiC) PiN diodes offer significant advantages to conventional fast-switching Silicon (Si) diodes for high power and fast switching applications. A wider band gap results in a breakdown voltage 10 times that of Si, so that a SiC device may have a thinner drift region for a given blocking voltage. [5] This leads to smaller, lighter devices for high voltage applications, as well as reduced forward conduction losses, faster reverse recovery time (faster turn-off), and lower-magnitude reverse recovery current. In addition, SiC devices have lower leakage current as compared to their Si counterparts, and a high thermal conductivity, potentially allowing the former to operate at higher temperatures with a smaller, lighter heatsink (or no heatsink at all).
1. View looking Northeast of Huber Breaker (left), Retail Coal ...
1. View looking Northeast of Huber Breaker (left), Retail Coal Storage Bins (center), and Power Station (right foreground) Photograph taken by George Harven - Huber Coal Breaker, Breaker, 101 South Main Street, Ashley, Luzerne County, PA
10-Qubit Entanglement and Parallel Logic Operations with a Superconducting Circuit
NASA Astrophysics Data System (ADS)
Song, Chao; Xu, Kai; Liu, Wuxin; Yang, Chui-ping; Zheng, Shi-Biao; Deng, Hui; Xie, Qiwei; Huang, Keqiang; Guo, Qiujiang; Zhang, Libo; Zhang, Pengfei; Xu, Da; Zheng, Dongning; Zhu, Xiaobo; Wang, H.; Chen, Y.-A.; Lu, C.-Y.; Han, Siyuan; Pan, Jian-Wei
2017-11-01
Here we report on the production and tomography of genuinely entangled Greenberger-Horne-Zeilinger states with up to ten qubits connecting to a bus resonator in a superconducting circuit, where the resonator-mediated qubit-qubit interactions are used to controllably entangle multiple qubits and to operate on different pairs of qubits in parallel. The resulting 10-qubit density matrix is probed by quantum state tomography, with a fidelity of 0.668 ±0.025 . Our results demonstrate the largest entanglement created so far in solid-state architectures and pave the way to large-scale quantum computation.
10-Qubit Entanglement and Parallel Logic Operations with a Superconducting Circuit.
Song, Chao; Xu, Kai; Liu, Wuxin; Yang, Chui-Ping; Zheng, Shi-Biao; Deng, Hui; Xie, Qiwei; Huang, Keqiang; Guo, Qiujiang; Zhang, Libo; Zhang, Pengfei; Xu, Da; Zheng, Dongning; Zhu, Xiaobo; Wang, H; Chen, Y-A; Lu, C-Y; Han, Siyuan; Pan, Jian-Wei
2017-11-03
Here we report on the production and tomography of genuinely entangled Greenberger-Horne-Zeilinger states with up to ten qubits connecting to a bus resonator in a superconducting circuit, where the resonator-mediated qubit-qubit interactions are used to controllably entangle multiple qubits and to operate on different pairs of qubits in parallel. The resulting 10-qubit density matrix is probed by quantum state tomography, with a fidelity of 0.668±0.025. Our results demonstrate the largest entanglement created so far in solid-state architectures and pave the way to large-scale quantum computation.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lisnyak, M.; Pipa, A. V.; Gorchakov, S., E-mail: gorchakov@inp-greifswald.de, E-mail: weltmann@inp-greifswald.de
2015-09-28
Spectroscopic investigations of free-burning vacuum arcs in diffuse mode with CuCr electrodes are presented. The experimental conditions of the investigated arc correspond to the typical system for vacuum circuit breakers. Spectra of six species Cu I, Cu II, Cu III, Cr I, Cr II, and Cr III have been analyzed in the wavelength range 350–810 nm. The axial intensity distributions were found to be strongly dependent on the ionization stage of radiating species. Emission distributions of Cr II and Cu II can be distinguished as well as the distributions of Cr III and Cu III. Information on the axial distribution wasmore » used to identify the spectra and for identification of overlapping spectral lines. The overview spectra and some spectral windows recorded with high resolution are presented. Analysis of axial distributions of emitted light, which originates from different ionization states, is presented and discussed.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kulikov, Konstantin N.; Nizamutdinov, Rinat A.; Abramov, Andrey N.
From 1959 up to 1991 nine civil nuclear powered ships were built in Russia: eight ice-breakers and one lash lighter carrier (cargo ship). At the present time three of them were taking out of service: ice-breaker 'Lenin' is decommissioned as a museum and is set for storage in the port of Murmansk, nuclear ice-breakers 'Arktika' and 'Sibir' are berthing. The ice-breakers carrying rad-wastes appear to be a possible source of radiation contamination of Murmansk region and Kola Bay because the ship long-term storage afloat has the negative effect on hull's structures. As the result of this under the auspices ofmore » the Federal Targeted Program 'Nuclear and Radiation Safety of Russia for 2008 and the period until 2015' the conception and projects of decommissioning of nuclear-powered ships are developed by the State corporation Rosatom with the involvement of companies of United Shipbuilding Corporation. In developing the principal provisions of conception of decommissioning and dismantling of icebreakers the technical and economic assessment of dismantling options in ship-repairing enterprises of North-West of Russia was performed. The paper contains description of options, research procedure, analysis of options of decommissioning and dismantling of nuclear ice-breakers, taking into account the principle of optimization of potential radioactive effect to personnel, human population and environment. The report's conclusions contain the recommendations for selection of option for development of nuclear icebreaker decommissioning and dismantling projects. (authors)« less
Broken Promises: Abstinence Pledging and Sexual and Reproductive Health
Paik, Anthony; Sanchagrin, Kenneth J.; Heimer, Karen
2016-01-01
Approximately 12% of girls and young women in the United States pledge abstinence. Yet most break their pledges, engaging in first intercourse before marriage. The extant literature reports few differences between pledge breakers and nonpledgers in sexually transmitted infections and nonmarital pregnancies. The present research maintains that previous studies may have obscured important differences in exposure risk and hypothesizes that female pledge breakers who have higher exposure risk are more likely to experience human papillomavirus (HPV) and nonmarital pregnancies. To test this hypothesis, this study uses the National Longitudinal Study of Adolescent to Adult Health, logistic regression, and event history modeling. The results show that, after accounting for differences in exposure risk, pledge breakers have higher risk of HPV and nonmarital pregnancy. As a set, the results are consistent with the argument that pledgers use condoms and contraceptives less consistently and highlight unintended consequences of abstinence promotion. PMID:27019521
A Solid-State, Rechargeable, Long Cycle Life Lithium-Air Battery (Postprint)
2010-01-01
lithium - ion battery , solid-state eletrolyte 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT: SAR 18. NUMBER OF PAGES 12 19a...electronics industry. The lithium ion battery business has grown into a multibillion dollar global industry, and a robust growth is anticipated in the future...rup- ture. A short-circuit in a lithium ion battery can cause it to ignite and explode. Some Li-ion cells are built with safety devices, which can
1999-02-23
pumped at frequencies up to 5.5 kHz (with 10-W pumping). At high pulse repetition rates the radius of the beam waist decreases to ~60 jum, owing to...1998) A 1.3-GHz SOI CMOS Test Chip for R. Berger Low-Power High -Speed Pulse W. G. Lyons Processing A. M. Soares IEEE J. Solid-State Circuits...Goodhue D. E. Mull J. M. Rossler Y. Royter C.G.Fonstad* /. Vac. Sei. Technol. Modeling the Microwave Impedance of High -Tc Long Josephson
Reliability Evaluation of Computer Systems.
1981-01-01
algorithms in hardware is not restricted by the designs of particular circuits. Applications could be made in new computer architectures; one candidate...pp. 137-148, IEEE, Chicago, Illinois, September 1963. (With J.F. Wakerly ) "Design of Low-Cost General-Purpose Self- Diagnosing Computers," Proc...34 Proc., IEEE Int’l Solid-State Circuits Conference, Philadelphia, Pennsylvania, February 16-18, 1977. (With J.F. Wakerly ) "Microcomputers in the
Transitional circuitry for studying the properties of DNA
NASA Astrophysics Data System (ADS)
Trubochkina, N.
2018-01-01
The article is devoted to a new view of the structure of DNA as an intellectual scheme possessing the properties of logic and memory. The theory of transient circuitry, developed by the author for optimal computer circuits, revealed an amazing structural similarity between mathematical models of transition silicon elements and logic and memory circuits of solid state transient circuitry and atomic models of parts of DNA.
Integral Battery Power Limiting Circuit for Intrinsically Safe Applications
NASA Technical Reports Server (NTRS)
Burns, Bradley M.; Blalock, Norman N.
2010-01-01
A circuit topology has been designed to guarantee the output of intrinsically safe power for the operation of electrical devices in a hazardous environment. This design uses a MOSFET (metal oxide semiconductor field-effect transistor) as a switch to connect and disconnect power to a load. A test current is provided through a separate path to the load for monitoring by a comparator against a preset threshold level. The circuit is configured so that the test current will detect a fault in the load and open the switch before the main current can respond. The main current passes through the switch and then an inductor. When a fault occurs in the load, the current through the inductor cannot change immediately, but the voltage drops immediately to safe levels. The comparator detects this drop and opens the switch before the current in the inductor has a chance to respond. This circuit protects both the current and voltage from exceeding safe levels. Typically, this type of protection is accomplished by a fuse or a circuit breaker, but in order for a fuse or a circuit breaker to blow or trip, the current must exceed the safe levels momentarily, which may be just enough time to ignite anything in a hazardous environment. To prevent this from happening, a fuse is typically current-limited by the addition of the resistor to keep the current within safe levels while the fuse reacts. The use of a resistor is acceptable for non-battery applications where the wasted energy and voltage drop across the resistor can be tolerated. The use of the switch and inductor minimizes the wasted energy. For example, a circuit runs from a 3.6-V battery that must be current-limited to 200 mA. If the circuit normally draws 10 mA, then an 18-ohm resistor would drop 180 mV during normal operation, while a typical switch (0.02 ohm) and inductor (0.97 ohm) would only drop 9.9 mV. From a power standpoint, the current-limiting resistor protection circuit wastes about 18 times more power than the switch and the inductor configuration. In the fault condition, both the resistor and the inductor react immediately. The resistor reacts by allowing more current to flow and dropping the voltage. Initially, the inductor reacts by dropping the voltage, and then by not allowing the current to change. When the comparator detects the drop in voltage, it opens the switch, thus preventing any further current flow. The inductor alone is not sufficient protection, because after the voltage drop has settled, the inductor would then allow the current to change, in this example, the current would be 3.7 A. In the fault condition, the resistor is flowing 200 mA until the fuse blows (anywhere from 1 ms to 100 s), while the switch and inductor combination is flowing about 2 A test current while monitoring for the fault to be corrected. Finally, as an additional safety feature, the circuit can be configured to hold the switch opened until both the load and source are disconnected.
Training Effectiveness Study of Simulator Usage and Its Impact on Live Fire Armor Gunnery
2014-06-01
including artillery Round loading and reloading sounds Loader’s “UP” Main gun , M240, and M2 machine gun firing Track clatter Engine and...functional TC’s hatch will not open M2 machine gun is not replicated on the AGTS Not all circuit breakers are supported from the display panels 18...Driver’s and loader’s stations are not simulated Of the limitations listed above, three are of most concern: the lack of M2 machine gun
Metal vapor arc switch electromagnetic accelerator technology
NASA Technical Reports Server (NTRS)
Mongeau, P. P.
1984-01-01
A multielectrode device housed in an insulator vacuum vessel, the metal vapor vacuum switch has high power capability and can hold off voltages up to the 100 kilovolt level. Such switches can be electronically triggered and can interrupt or commutate at a zero current crossing. The physics of arc initiation, arc conduction, and interruption are examined, including material considerations; inefficiencies; arc modes; magnetic field effects; passive and forced extinction; and voltage recovery. Heating, electrode lifetime, device configuration, and external circuit configuration are discussed. The metal vapor vacuum switch is compared with SCRs, GTOs, spark gaps, ignitrons, and mechanical breakers.
Chemical Processing of Electrons and Holes.
ERIC Educational Resources Information Center
Anderson, Timothy J.
1990-01-01
Presents a synopsis of four lectures given in an elective senior-level electronic material processing course to introduce solid state electronics. Provides comparisons of a large scale chemical processing plant and an integrated circuit. (YP)
Electrical and electronic devices and components: A compilation
NASA Technical Reports Server (NTRS)
1975-01-01
Components and techniques which may be useful in the electronics industry are described. Topics discussed include transducer technology, printed-circuit technology, solid state devices, MOS transistors, Gunn device, microwave antennas, and position indicators.
A front end readout electronics ASIC chip for position sensitive solid state detectors
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kravis, S.D.; Tuemer, T.O.; Visser, G.J.
1998-12-31
A mixed signal Application Specific Integrated Circuit (ASIC) chip for front end readout electronics of position sensitive solid state detectors has been manufactured. It is called RENA (Readout Electronics for Nuclear Applications). This chip can be used for both medical and industrial imaging of X-rays and gamma rays. The RENA chip is a monolithic integrated circuit and has 32 channels with low noise high input impedance charge sensitive amplifiers. It works in pulse counting mode with good energy resolution. It also has a self triggering output which is essential for nuclear applications when the incident radiation arrives at random. Different,more » externally selectable, operational modes that includes a sparse readout mode is available to increase data throughput. It also has externally selectable shaping (peaking) times.« less
NASA Astrophysics Data System (ADS)
Liu, Chuncheng; Wang, Chongyang; Mao, Long; Zha, Chuanming
2016-11-01
Substation high voltage electrical equipment such as mutual inductor, circuit interrupter, disconnecting switch, etc., has played a key role in maintaining the normal operation of the power system. When the earthquake disaster, the electrical equipment of the porcelain in the transformer substation is the most easily to damage, causing great economic losses. In this paper, using the method of numerical analysis, the establishment of a typical high voltage electrical equipment of three dimensional finite element model, to study the seismic response of a typical SF6 circuit breaker, at the same time, analysis and contrast the installation ring tuned mass damper (TMD damper for short), by changing the damper damping coefficient and the mass block, install annular TMD vibration control effect is studied. The results of the study for guiding the seismic design of high voltage electrical equipment to provide valuable reference.
Analysis of switching surges generated by current interruption in an energy-storge coil
NASA Astrophysics Data System (ADS)
Chowdhuri, P.
1981-10-01
The transient voltages which are generated when the current in a large magnetic energy storage coil is interruped by a dc vacuum circuit breaker is analyzed. The effect of the various parameters in the circuit on the transient voltage is dicussed. The self inductance of the dump resistor must be minimized to control the generated transient. Contrary to general belief, a capacitor across the coil is not an effective surge suppressor. In fact, the capacitor may excite oscillations of higher magnitude. However, a capacitor, in addition to a surge suppressor, may be used to modify the frequency components of the transient voltage so that these frequency components are not coincident with the natural frequencies of the coil. Otherwise, resonant oscillations inside the coil may attain damaging magnitudes. The capacitor would also reduce the steepness of the wavefront of the transient across the coil, thus reducing the nonlinear voltage distribution inside the coil.
Nanogap Electrodes towards Solid State Single-Molecule Transistors.
Cui, Ajuan; Dong, Huanli; Hu, Wenping
2015-12-01
With the establishment of complementary metal-oxide-semiconductor (CMOS)-based integrated circuit technology, it has become more difficult to follow Moore's law to further downscale the size of electronic components. Devices based on various nanostructures were constructed to continue the trend in the minimization of electronics, and molecular devices are among the most promising candidates. Compared with other candidates, molecular devices show unique superiorities, and intensive studies on molecular devices have been carried out both experimentally and theoretically at the present time. Compared to two-terminal molecular devices, three-terminal devices, namely single-molecule transistors, show unique advantages both in fundamental research and application and are considered to be an essential part of integrated circuits based on molecular devices. However, it is very difficult to construct them using the traditional microfabrication techniques directly, thus new fabrication strategies are developed. This review aims to provide an exclusive way of manufacturing solid state gated nanogap electrodes, the foundation of constructing transistors of single or a few molecules. Such single-molecule transistors have the potential to be used to build integrated circuits. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Self-healing liquid/solid state battery
DOE Office of Scientific and Technical Information (OSTI.GOV)
Burke, Paul J.; Chung, Brice H.V.; Phadke, Satyajit R.
A battery system that exchanges energy with an external device is provided. The battery system includes a positive electrode having a first metal or alloy, a negative electrode having a second metal or alloy, and an electrolyte including a salt of the second metal or alloy. The positive electrode, the negative electrode, and the electrolyte are in a liquid phase at an operating temperature during at least one portion of operation. The positive electrode is entirely in a liquid phase in one charged state and includes a solid phase in another charged state. The solid phase of the positive electrodemore » includes a solid intermetallic formed by the first and the second metals or alloys. Methods of storing electrical energy from an external circuit using such a battery system are also provided.« less
Molecular dynamics simulations of Aβ fibril interactions with β-sheet breaker peptides.
Bruce, Neil J; Chen, Deliang; Dastidar, Shubhra G; Marks, Gabriel E; Schein, Catherine H; Bryce, Richard A
2010-11-01
Accumulation and aggregation of the 42-residue amyloid-β (Aβ) protein fragment, which originates from the cleavage of amyloid precursor protein by β and γ secretase, correlates with the pathology of Alzheimer's disease (AD). Possible therapies for AD include peptides based on the Aβ sequence, and recently identified small molecular weight compounds designed to mimic these, that interfere with the aggregation of Aβ and prevent its toxic effects on neuronal cells in culture. Here, we use molecular dynamics simulations to compare the mode of interaction of an active (LPFFD) and inactive (LHFFD) β-sheet breaker peptide with an Aβ fibril structure from solid-state NMR studies. We found that LHFFD had a weaker interaction with the fibril than the active peptide, LPFFD, from geometric and energetic considerations, as estimated by the MM/PBSA approach. Cluster analysis and computational alanine scanning identified important ligand-fibril contacts, including a possible difference in the effect of histidine on ligand-fibril π-stacking interactions, and the role of the proline residue in establishing contacts that compete with those essential for maintenance of the inter-monomer β-sheet structure of the fibril. Our results show that molecular dynamics simulations can be a useful way to classify the stability of docking sites. These mechanistic insights into the ability of LPFFD to reverse aggregation of toxic Aβ will guide the redesign of lead compounds, and aid in developing realistic therapies for AD and other diseases of protein aggregation. Copyright © 2010 Elsevier Inc. All rights reserved.
1983-01-01
Physique de l’Atmosphire et Environnement terrestre 71 09 - Information, Documentation et Informatique 74 10 - Thimes gin~raux (pluridisciplinaires) et...March Louisiana (US) Fiber Communication Optical Communications IEEE Fibre Optics Electro-Optics 02-08 7-9 March Baden-Baden VDE -IEEE Specialists...Conference on Very Large Electronic Systems VDE (GE) Scale Integrated Circuits Solid State Devices IEEE Integrated Circuits Engineering Design Fabrication
The 20 GHz spacecraft IMPATT solid state transmitter
NASA Technical Reports Server (NTRS)
Best, T.; Ngan, Y. C.
1986-01-01
The engineering development of a solid-state transmitter amplifier operating in the 20-GHz frequency range is described. This effort involved a multitude of disciplines including IMPATT device development, circulator design, multiple-diode circuit design, and amplifier integration and test. The objective was to develop a transmitter amplifier demonstrating the feasibility of providing an efficient, reliable, lightweight solid-state transmitter to be flown on a 30 to 20 GHz communication demonstration satellite. The work was done under contract from NASA/Lewis Research Center for a period of three years. The result was the development of a GaAs IMPACT diode amplifier capable of an 11-W CW output power and a 2-dB bandwidth of 300 MHz. GaAs IMPATT diodes incorporating diamond heatsink and double-Read doping profile capable of 5.3-W CW oscillator output power and 15.5% efficiency were developed. Up to 19% efficiency was also observed for an output power level of 4.4 W. High performance circulators with a 0.2 dB inserting loss and bandwidth of 5 GHz have also been developed. These represent a significant advance in both device and power combiner circuit technologies in K-band frequencies.
NASA Technical Reports Server (NTRS)
Fleurial, J. P.; Snyder, G. J.; Patel, J.; Huang, C. K.; Ryan, M. A.; Averback, R.; Chen, G.; Hill, C.
2002-01-01
The Jet Propulsion Laboratory has been actively pursuing the development of thermoelectric micro/nanodevices that can be fabricated using a combination of electrochemical deposition and integrated circuit processing techniques.
Combined analysis of energy band diagram and equivalent circuit on nanocrystal solid
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kano, Shinya, E-mail: kano@eedept.kobe-u.ac.jp, E-mail: fujii@eedept.kobe-u.ac.jp; Sasaki, Masato; Fujii, Minoru, E-mail: kano@eedept.kobe-u.ac.jp, E-mail: fujii@eedept.kobe-u.ac.jp
We investigate a combined analysis of an energy band diagram and an equivalent circuit on nanocrystal (NC) solids. We prepared a flat silicon-NC solid in order to carry out the analysis. An energy band diagram of a NC solid is determined from DC transport properties. Current-voltage characteristics, photocurrent measurements, and conductive atomic force microscopy images indicate that a tunneling transport through a NC solid is dominant. Impedance spectroscopy gives an equivalent circuit: a series of parallel resistor-capacitors corresponding to NC/metal and NC/NC interfaces. The equivalent circuit also provides an evidence that the NC/NC interface mainly dominates the carrier transport throughmore » NC solids. Tunneling barriers inside a NC solid can be taken into account in a combined capacitance. Evaluated circuit parameters coincide with simple geometrical models of capacitances. As a result, impedance spectroscopy is also a useful technique to analyze semiconductor NC solids as well as usual DC transport. The analyses provide indispensable information to implement NC solids into actual electronic devices.« less
Mass-spectroscopic study of the influence of nozzle material on high-pressure SF6 arcs
NASA Astrophysics Data System (ADS)
Meier, R.; Kneubühl, F. K.; Schötzau, H. J.
1989-03-01
The interrupting capability of a gas-blast high-voltage circuit breaker (CB) is mainly determined by the self-induced pressure rise caused by the thermal arc energy, the composition of the arc plasma and the chemical reactions occuring during and after current interruption. We have studied the nozzle materials boron nitride (BN), quartz (SiO2), polytetrafluoroethylene (PTFE), ethylene-tetrafluoroethylene (ETFE), polyethylene (PE) and epoxy resin (ER) with respect to their influence on these processes with the aid of a model circuit breaker (MCB). Direct measurements of the arc-induced pressure rise reveal that the portion of the arc energy available for the pressure rise varies greatly (˜20% 65%) with the properties of the nozzle material. Nozzle erosion is significantly higher for materials with high values (e.g. polymers). Therefore, the lifetime of polymer nozzles is considerably shorter than that of ceramic nozzles. We have investigated the influence of the nozzle material on the decomposition products formed in the arc discharge of our MCB by studying the composition and time dependence of these products. The MCB was directly attached to the time-of-flight mass spectrometer (TOFMS) with the aid of a molecular-beam sampling system, which allowed real-time measurements of the arced gas during and after current interruption, thus providing information on the ablation mechanism and on the reaction kinetics of vaporised nozzle material with dissociated SF6. The most abundant long-lived reaction products are SF4, SOF2, C2H2, CO, and CS2. Their formation rates have been determined as functions of the nozzle material. With respect to quantities and properties of decomposition products, ceramics are superior to polymers since they form only small concentrations of corrosive and toxic products.
Putting reins on the brain. How the body and environment use it
Dotov, Dobromir G.
2014-01-01
Radical embodied cognitive neuroscience (RECN) will probably rely on dynamical systems theory (DST) and complex systems theory for methods and formalism. Yet, there have been plenty of non-radical neurodynamicists out there for quite some time. How much of their work fits with radical embodied cognitive science, what do they need RECN for, and what are the inconsistencies between RECN and established neurodynamics that would have to be resolved? This paper is both theoretical hypothesis and review. First, it provides a brief overview of the typical, purely structural considerations why the central nervous systems (CNS) should be treated as a nonlinear dynamical system and what this entails. The reader will learn about the circular causality enclosing brain and behavior and different attempts to formalize this circularity. Then, three different attempts at linking dynamics and theory of brain function are described in more detail and criticized. A fourth method based on ecological psychology could fix some of the issues that the others encounter. It is argued that studying self-organization of the brain without taking its ecological embedding into account is insufficient. Finally, based on existing theoretical work we propose two roles that the CNS has to be fulfilling in order to allow an animal to behave adequately in its niche. In its first role the CNS has to be enslaved easily by patterns of behavior that guide the animal through its environment. In the second role the brain has to flexibly switch among patterns, what can be called the metastable circuit breaker. The relevance of this idea is supported using certain motor symptoms of Parkinson’s disease (PD). These symptoms can be explained as consequent to an excessive stability of the (metastable) circuit breaker. PMID:25346675
Deterministic transfer of an unknown qutrit state assisted by the low-Q microwave resonators
NASA Astrophysics Data System (ADS)
Liu, Tong; Zhang, Yang; Yu, Chang-Shui; Zhang, Wei-Ning
2017-05-01
Qutrits (i.e., three-level quantum systems) can be used to achieve many quantum information and communication tasks due to their large Hilbert spaces. In this work, we propose a scheme to transfer an unknown quantum state between two flux qutrits coupled to two superconducting coplanar waveguide resonators. The quantum state transfer can be deterministically achieved without measurements. Because resonator photons are virtually excited during the operation time, the decoherences caused by the resonator decay and the unwanted inter-resonator crosstalk are greatly suppressed. Moreover, our approach can be adapted to other solid-state qutrits coupled to circuit resonators. Numerical simulations show that the high-fidelity transfer of quantum state between the two qutrits is feasible with current circuit QED technology.
Efficient transfer of an arbitrary qutrit state in circuit quantum electrodynamics.
Liu, Tong; Xiong, Shao-Jie; Cao, Xiao-Zhi; Su, Qi-Ping; Yang, Chui-Ping
2015-12-01
Compared with a qubit, a qutrit (i.e., three-level quantum system) has a larger Hilbert space and thus can be used to encode more information in quantum information processing and communication. Here, we propose a method to transfer an arbitrary quantum state between two flux qutrits coupled to two resonators. This scheme is simple because it only requires two basic operations. The state-transfer operation can be performed fast because only resonant interactions are used. Numerical simulations show that the high-fidelity transfer of quantum states between the two qutrits is feasible with current circuit-QED technology. This scheme is quite general and can be applied to accomplish the same task for other solid-state qutrits coupled to resonators.
NASA Astrophysics Data System (ADS)
Kim, Jun Young; Kim, Tae Ho; Kim, Dong Young; Park, Nam-Gyu; Ahn, Kwang-Duk
Novel thixotropic gel electrolytes have been successfully prepared by utilizing oligomeric poly(ethylene oxide) (PEO)-based bis-imidazolium diiodide salts and hydrophilic silica nanoparticles for application in quasi-solid-state dye-sensitized solar cells (DSSCs). The thixotropic gel-state of the ionic liquid-based composite electrolytes is confirmed by observing the typical hysteresis loop and temporary hydrogen bonding. On using the PEO-based composite electrolyte, a quasi-solid-state DSSC exhibited highly improved properties such as easy penetration of the electrolyte into the cell without leakage, long-term stability, high open-circuit voltage without the use of 4- tert-butylpyridine, and a high energy-conversion efficiency of 5.25% under AM 1.5 illumination (100 mW cm -2).
Facile fabrication of all-solid-state SnO2/NiCo2O4 biosensor for self-powered glucose detection
NASA Astrophysics Data System (ADS)
Cai, Bin; Mao, Weiwei; Ye, Zhizhen; Huang, Jingyun
2016-09-01
With increasing attention on daily diabetes management, we develop an all-solid-state self-powered glucose biosensor, with simultaneous solar energy conversion, electrochemical energy storage and glucose sensing. The SnO2 nanosheet arrays are used to obtain photogenerated electron-hole pairs, and rhombus-shaped NiCo2O4 nanorod arrays are developed for solar energy storage. A stable open circuit voltage ~0.58 V is obtained after being fully charged, which is a suitable voltage for the oxidation of glucose. The biosensor can work under two different modes without any external bias voltage, and both show large linear range and excellent selectivity. Under the sunlight, photocurrent shows a sensitive decrease upon different glucose additions. Meanwhile, in the dark condition, the open circuit voltage of the charged biosensor also exhibits a corresponding response to glucose.
NASA Technical Reports Server (NTRS)
Schwarz, F. C. (Inventor)
1974-01-01
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.
V-band integrated quadriphase modulator
NASA Technical Reports Server (NTRS)
Grote, A.; Chang, K.
1983-01-01
A V-band integrated circuit quadriphase shift keyed modulator/exciter for space communications systems was developed. Intersatellite communications systems require direct modulation at 60 GHz to enhance signal processing capability. For most systems, particularly space applications, small and lightweight components are essential to alleviate severe system design constraints. Thus to achieve wideband, high data rate systems, direct modulation techniques at millimeter waves using solid state integrated circuit technology are an integral part of the overall technology developments.
A Design Methodology for Switched-Capacitor DC-DC Converters
2009-05-21
phase piezoelectric energy harvesters ,” IEEE International Solid-State Circuits Conference, pp. 302–303, Feb. 2008. [20] P. Hazucha, G. Schrom, J. Hahn...2007. [42] Y. K. Ramadass and A. P. Chandrakasan, “An efficient piezoelectric energy- harvesting interface circuit using a bias-flip rectifier and...made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. To copy otherwise, to
Fuel dissipater for pressurized fuel cell generators
Basel, Richard A.; King, John E.
2003-11-04
An apparatus and method are disclosed for eliminating the chemical energy of fuel remaining in a pressurized fuel cell generator (10) when the electrical power output of the fuel cell generator is terminated during transient operation, such as a shutdown; where, two electrically resistive elements (two of 28, 53, 54, 55) at least one of which is connected in parallel, in association with contactors (26, 57, 58, 59), a multi-point settable sensor relay (23) and a circuit breaker (24), are automatically connected across the fuel cell generator terminals (21, 22) at two or more contact points, in order to draw current, thereby depleting the fuel inventory in the generator.
Mobile Centers For Secondary Power Distribution
NASA Technical Reports Server (NTRS)
Mears, Robert L.
1990-01-01
Concept for distribution of 60-Hz ac power in large building devoted to assembly and testing of equipment improves safety, reduces number of outlets and lengthy cables, and readily accommodates frequent changes in operations and configuration. Power from floor recess fed via unobtrusive cable to portable power management center. A cart containing variety of outlets and circuit breakers, wheeled to convenient location near equipment to be assembled or tested. Power distribution system presents larger range of operational configurations than fixed location. Meets tighter standards to feed computers and delicate instruments. Industrial-grade power suitable for power tools and other hardware. Three-phase and single-phase outlets available from each.
NASA Technical Reports Server (NTRS)
Chan, J. L.; Sun, C.
1983-01-01
The engineering development of a solid state transmitter amplifier operating in the 20 GHz frequency band. The development effort involved a variety of disciplines including IMPATT device development, circulator design, simple and multiple diode circuits designs, and amplifier integration and test.
NASA Astrophysics Data System (ADS)
Takada, Shunji; Ihama, Mikio; Inuiya, Masafumi
2006-02-01
Digital still cameras overtook film cameras in Japanese market in 2000 in terms of sales volume owing to their versatile functions. However, the image-capturing capabilities such as sensitivity and latitude of color films are still superior to those of digital image sensors. In this paper, we attribute the cause for the high performance of color films to their multi-layered structure, and propose the solid-state image sensors with stacked organic photoconductive layers having narrow absorption bands on CMOS read-out circuits.
High-power pulse repetitive HF(DF) laser with a solid-state pump generator
DOE Office of Scientific and Technical Information (OSTI.GOV)
Velikanov, S D; Domazhirov, A P; Zaretskiy, N A
2015-11-30
Operation of a repetitively pulsed electric-discharge HF(DF) laser with an all-solid-state pump generator based on FID switches is demonstrated. The energy stored in the pump generator capacitors was 880 J at an open-circuit voltage of 240 kV and a discharge pulse repetition rate of 25 Hz. The specific energy extractions were 3.8 and 3.4 J L{sup -1} for the HF and DF lasers, respectively. The possibilities of improving the output laser characteristics are discussed. (lasers)
Characterization of resonant tunneling diodes for microwave and millimeter-wave detection
NASA Technical Reports Server (NTRS)
Mehdi, I.; East, J. R.; Haddad, G. I.
1991-01-01
The authors report on the direct detection capabilities of resonant tunneling diodes in the 10-100 GHz range. An open circuit voltage sensitivity of 1750 mV/mW (in Ka-band) was measured. This is higher than the sensitivity of comparatively based commercially available solid-state detectors. The detector properties are a strong function of diode bias and the measured tangential signal sensitivity (-32 dBm at Ka-band with 1-MHz bandwidth) and the dynamic range (25 dB) of the diode are smaller compared to other solid-state detectors.
Nordstrom, Eric J; Bittner, Katie C; McGrath, Michael J; Parks, Clinton R; Burton, Frank H
2015-12-10
The brain circuits underlying tics in Tourette׳s syndrome (TS) are unknown but thought to involve cortico/amygdalo-striato-thalamo-cortical (CSTC) loop hyperactivity. We previously engineered a transgenic mouse "circuit model" of TS by expressing an artificial neuropotentiating transgene (encoding the cAMP-elevating, intracellular A1 subunit of cholera toxin) within a small population of dopamine D1 receptor-expressing somatosensory cortical and limbic neurons that hyperactivate cortico/amygdalostriatal glutamatergic output circuits thought to be hyperactive in TS and comorbid obsessive-compulsive (OC) disorders. As in TS, these D1CT-7 ("Ticcy") transgenic mice׳s tics were alleviated by the TS drugs clonidine and dopamine D2 receptor antagonists; and their chronic glutamate-excited striatal motor output was unbalanced toward hyperactivity of the motoric direct pathway and inactivity of the cataleptic indirect pathway. Here we have examined whether these mice׳s tics are countered by drugs that "break" sequential elements of their hyperactive cortical/amygdalar glutamatergic and efferent striatal circuit: anti-serotonoceptive and anti-noradrenoceptive corticostriatal glutamate output blockers (the serotonin 5-HT2a,c receptor antagonist ritanserin and the NE alpha-1 receptor antagonist prazosin); agmatinergic striatothalamic GABA output blockers (the presynaptic agmatine/imidazoline I1 receptor agonist moxonidine); and nigrostriatal dopamine output blockers (the presynaptic D2 receptor agonist bromocriptine). Each drug class alleviates tics in the Ticcy mice, suggesting a hyperglutamatergic CSTC "tic circuit" could exist in TS wherein cortical/amygdalar pyramidal projection neurons׳ glutamatergic overexcitation of both striatal output neurons and nigrostriatal dopaminergic modulatory neurons unbalances their circuit integration to excite striatothalamic output and create tics, and illuminating new TS drug strategies. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.
28. View looking Northeast, Huber Breaker (left), Retail Coal Storage ...
28. View looking Northeast, Huber Breaker (left), Retail Coal Storage Bins (Center) Power Plant (right) Photograph taken by George Harven - Huber Coal Breaker, 101 South Main Street, Ashley, Luzerne County, PA
30. Looking to Huber Breaker (left), Retail Coal Storage Bins ...
30. Looking to Huber Breaker (left), Retail Coal Storage Bins (center), and Power Plant (right) Photograph taken by George Harven - Huber Coal Breaker, 101 South Main Street, Ashley, Luzerne County, PA
Thompson, J.L.; Upton, H.A.
1999-04-27
Breaker valve assemblies for a simplified boiling water nuclear reactor are described. The breaker valve assembly, in one form, includes a valve body and a breaker valve. The valve body includes an interior chamber, and an inlet passage extends from the chamber and through an inlet opening to facilitate transporting particles from outside of the valve body to the interior chamber. The breaker valve is positioned in the chamber and is configured to substantially seal the inlet opening. Particularly, the breaker valve includes a disk which is sized to cover the inlet opening. The disk is movably coupled to the valve body and is configured to move substantially concentrically with respect to the valve opening between a first position, where the disk completely covers the inlet opening, and a second position, where the disk does not completely cover the inlet opening. 1 fig.
Thompson, Jeffrey L.; Upton, Hubert Allen
1999-04-27
Breaker valve assemblies for a simplified boiling water nuclear reactor are described. The breaker valve assembly, in one form, includes a valve body and a breaker valve. The valve body includes an interior chamber, and an inlet passage extends from the chamber and through an inlet opening to facilitate transporting particles from outside of the valve body to the interior chamber. The breaker valve is positioned in the chamber and is configured to substantially seal the inlet opening. Particularly, the breaker valve includes a disk which is sized to cover the inlet opening. The disk is movably coupled to the valve body and is configured to move substantially concentrically with respect to the valve opening between a first position, where the disk completely covers the inlet opening, and a second position, where the disk does not completely cover the inlet opening.
44. Blue Coal Corporation Office Building (foreground), Huber Breaker (left), ...
44. Blue Coal Corporation Office Building (foreground), Huber Breaker (left), Retail Coal Storage Bins (far center) Photograph taken by George Harven - Huber Coal Breaker, 101 South Main Street, Ashley, Luzerne County, PA
Detail of motor control cabinet and field breakers. Control cabinet ...
Detail of motor control cabinet and field breakers. Control cabinet and breaker panel built by Cutler-Hammer - Wellton-Mohawk Irrigation System, Pumping Plant No. 3, South of Interstate 8, Wellton, Yuma County, AZ
31. Panoramic shot, Huber Breaker (left), Retail Coal Storage Bins ...
31. Panoramic shot, Huber Breaker (left), Retail Coal Storage Bins (center), Boney Elevator (right) Photographs taken by Joseph E.B. Elliot - Huber Coal Breaker, 101 South Main Street, Ashley, Luzerne County, PA
ERIC Educational Resources Information Center
Carangelo, Pasquale R.; Janeczek, Anthony J.
Materials are provided for a two-semester digital and microprocessor technician postgraduate program. Prerequisites stated for the program include a background in DC and AC theory, solid state devices, basic circuit fundamentals, and basic math. A chronology of major topics and a listing of course objectives appear first. Theory outlines for each…
A novel pixellated solid-state photon detector for enhancing the Everhart-Thornley detector.
Chuah, Joon Huang; Holburn, David
2013-06-01
This article presents a pixellated solid-state photon detector designed specifically to improve certain aspects of the existing Everhart-Thornley detector. The photon detector was constructed and fabricated in an Austriamicrosystems 0.35 µm complementary metal-oxide-semiconductor process technology. This integrated circuit consists of an array of high-responsivity photodiodes coupled to corresponding low-noise transimpedance amplifiers, a selector-combiner circuit and a variable-gain postamplifier. Simulated and experimental results show that the photon detector can achieve a maximum transimpedance gain of 170 dBΩ and minimum bandwidth of 3.6 MHz. It is able to detect signals with optical power as low as 10 nW and produces a minimum signal-to-noise ratio (SNR) of 24 dB regardless of gain configuration. The detector has been proven to be able to effectively select and combine signals from different pixels. The key advantages of this detector are smaller dimensions, higher cost effectiveness, lower voltage and power requirements and better integration. The photon detector supports pixel-selection configurability which may improve overall SNR and also potentially generate images for different analyses. This work has contributed to the future research of system-level integration of a pixellated solid-state detector for secondary electron detection in the scanning electron microscope. Copyright © 2013 Wiley Periodicals, Inc.
29. Another view looking Northeast closer to Huber Breaker (left), ...
29. Another view looking Northeast closer to Huber Breaker (left), Retail Coal Storage Bins (Center), Power Plant (right) Photograph taken by George Harven - Huber Coal Breaker, 101 South Main Street, Ashley, Luzerne County, PA
40 CFR Table 31 to Subpart G of... - Typical Number of Vacuum Breakers, NF6 and Roof Drains, a NF7
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 10 2013-07-01 2013-07-01 false Typical Number of Vacuum Breakers, NF6..., and Wastewater Pt. 63, Subpt. G, Table 31 Table 31 to Subpart G of Part 63—Typical Number of Vacuum Breakers, NF6 and Roof Drains, a NF7 Tank diameter D (feet) b No. of vacuum breakers, NF6 Pontoon roof...
Ji, Shiqi; Zheng, Sheng; Wang, Fei; ...
2017-07-06
The temperature-dependent characteristics of the third-generation 10-kV/20-A SiC MOSFET including the static characteristics and switching performance are carried out in this paper. The steady-state characteristics, including saturation current, output characteristics, antiparallel diode, and parasitic capacitance, are tested. Here, a double pulse test platform is constructed including a circuit breaker and gate drive with >10-kV insulation and also a hotplate under the device under test for temperature-dependent characterization during switching transients. The switching performance is tested under various load currents and gate resistances at a 7-kV dc-link voltage from 25 to 125 C and compared with previous 10-kV MOSFETs. A simplemore » behavioral model with its parameter extraction method is proposed to predict the temperature-dependent characteristics of the 10-kV SiC MOSFET. The switching speed limitations, including the reverse recovery of SiC MOSFET's body diode, overvoltage caused by stray inductance, crosstalk, heat sink, and electromagnetic interference to the control are discussed based on simulations and experimental results.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ji, Shiqi; Zheng, Sheng; Wang, Fei
The temperature-dependent characteristics of the third-generation 10-kV/20-A SiC MOSFET including the static characteristics and switching performance are carried out in this paper. The steady-state characteristics, including saturation current, output characteristics, antiparallel diode, and parasitic capacitance, are tested. Here, a double pulse test platform is constructed including a circuit breaker and gate drive with >10-kV insulation and also a hotplate under the device under test for temperature-dependent characterization during switching transients. The switching performance is tested under various load currents and gate resistances at a 7-kV dc-link voltage from 25 to 125 C and compared with previous 10-kV MOSFETs. A simplemore » behavioral model with its parameter extraction method is proposed to predict the temperature-dependent characteristics of the 10-kV SiC MOSFET. The switching speed limitations, including the reverse recovery of SiC MOSFET's body diode, overvoltage caused by stray inductance, crosstalk, heat sink, and electromagnetic interference to the control are discussed based on simulations and experimental results.« less
System-Level Integrated Circuit (SLIC) development for phased array antenna applications
NASA Technical Reports Server (NTRS)
Shalkhauser, K. A.; Raquet, C. A.
1991-01-01
A microwave/millimeter wave system-level integrated circuit (SLIC) being developed for use in phased array antenna applications is described. The program goal is to design, fabricate, test, and deliver an advanced integrated circuit that merges radio frequency (RF) monolithic microwave integrated circuit (MMIC) technologies with digital, photonic, and analog circuitry that provide control, support, and interface functions. As a whole, the SLIC will offer improvements in RF device performance, uniformity, and stability while enabling accurate, rapid, repeatable control of the RF signal. Furthermore, the SLIC program addresses issues relating to insertion of solid state devices into antenna systems, such as the reduction in number of bias, control, and signal lines. Program goals, approach, and status are discussed.
System-level integrated circuit (SLIC) development for phased array antenna applications
NASA Technical Reports Server (NTRS)
Shalkhauser, K. A.; Raquet, C. A.
1991-01-01
A microwave/millimeter wave system-level integrated circuit (SLIC) being developed for use in phased array antenna applications is described. The program goal is to design, fabricate, test, and deliver an advanced integrated circuit that merges radio frequency (RF) monolithic microwave integrated circuit (MMIC) technologies with digital, photonic, and analog circuitry that provide control, support, and interface functions. As a whole, the SLIC will offer improvements in RF device performance, uniformity, and stability while enabling accurate, rapid, repeatable control of the RF signal. Furthermore, the SLIC program addresses issues relating to insertion of solid state devices into antenna systems, such as the reduction in number of bias, control, and signal lines. Program goals, approach, and status are discussed.
Automatic Locker Key With Barcode Based Microcontroller Atmega 8535
NASA Astrophysics Data System (ADS)
Fahmi, M. Irfan; Efendi Hutagalung, Jhonson
2017-12-01
MCB (miniature circuit breaker) is an electromagnetic device that embodies complete enclosure in a molded insulating material. The main function of an MCB is to switch the circuit, i.e., to open the circuit (which has been connected to it) automatically when the current passing through it (MCB) exceeds the value for which it is set. Unlike fuse, an MCB can be easily reset and thus offers improved operational safety and greater convenience without incurring large operating cost.The principal of operation is simple. In simple terms MCB is a switch which automatically turns off when the current flowing through it passes the maximum allowable limit. Generally MCB are designed to protect against over current and over temperature faults (over heating). Sometimes the overload the current through the bimetal causes to raise the temperature of it. The heat generated within the bimetal itself enough to cause deflection due to thermal expansion of metals. This solution is used by LDR, and LM 35 as the sencor to control center. Therefore it is very important because it is related about local control switches, isolating switches against faults and overload protection devices for installations or specific equipments or appliances
Marx Generator Charged via Biperiodic Resonant Cascaded Transformers
NASA Astrophysics Data System (ADS)
Potter, Rudolf H.
In this work, a novel method for charging solid state Marx generators is described for the first time. We first review the utility of modulators for powering high power microwave devices. The principal of operation of the Marx generator is then described starting with the classic topology and leading to solid state topologies. The concept of a generalized Marx generator is introduced and several methods of charging are discussed. A resonant cascaded transformers topology emerges from this discussion. Resonant modes are discussed and the topology is refined to take advantage of the pi/2 mode leading to the circuit that is the focus of this work. We begin our analysis of this circuit by considering the corresponding infinite biperiodic system and derive the characteristic dispersion relation. Motivation for closing the stopband is discussed and benefits of the pi/2 mode are noted. We proceed next to derive the matrix equation for the corresponding lossless system of coupled oscillators. To test and verify the analytic work, a five cell benchtop prototype of the charging system is built and its resonant modes are determined empirically. Capacitors in odd numbered resonators are each connected to the input of a voltage doubler circuit and high voltage dc is generated. A MOSFET is added to the output of each doubler circuit and pulsed output is demonstrated. A SPICE simulation of the physical circuit is created. The mode frequencies from the simulation are in good agreement with those measured and calculated. A practical high-power design is considered for the E2V/Teledyne MG7095 magnetron and simulated in SPICE.
32. INTERIOR VIEW LOOKING NORTH ON THE ORE BREAKER LEVEL. ...
32. INTERIOR VIEW LOOKING NORTH ON THE ORE BREAKER LEVEL. THE ORE BREAKER, A BLAKE JAW CRUSHER, IS IN THE BOX IN THE LEFT OF THE PHOTOGRAPH, THE ORE TO BE BROKEN IS FED INTO THE OPENING ON THE FLOOR AND NEXT TO ORE BREAKER BOX. THE GRIZZLY BARS ARE ON THE RIGHT AND THE PULLEYS FROM THE POWER SYSTEM ARE OVERHEAD. - Standard Gold Mill, East of Bodie Creek, Northeast of Bodie, Bodie, Mono County, CA
Competencies for Articulation: Electronics.
ERIC Educational Resources Information Center
Southeast Community Coll., Lincoln, NE.
Designed to help articulate vocational education student progress from one level of training to another and to employment, this electronics education guide lists competencies for soldering; performing basic operations with test equipment; servicing basic logic circuits; servicing DC power supplies; servicing solid state amplifiers; and servicing…
De, Bibekananda; Yadav, Amit; Khan, Salman; Kar, Kamal K
2017-06-14
Development of printable and flexible energy storage devices is one of the most promising technologies for wearable electronics in textile industry. The present work involves the design of a printable and flexible all-solid-state rechargeable battery for wearable electronics in textile applications. Copper-coated carbon fiber is used to make a poly(ethylene oxide) (PEO)-based polymer nanocomposite for a flexible and conductive current collector layer. Lithium iron phosphate (LiFePO 4 ) and titanium dioxide (TiO 2 ) are utilized to prepare the cathode and anode layers, respectively, with PEO and carbon black composites. The PEO- and Li salt-based solid composite separator layer is utilized for the solid-state and safe electrolyte. Fabrication of all these layers and assembly of them through coating on fabrics are performed in the open atmosphere without using any complex processing, as PEO prevents the degradation of the materials in the open atmosphere. The performance of the battery is evaluated through charge-discharge and open-circuit voltage analyses. The battery shows an open-circuit voltage of ∼2.67 V and discharge time ∼2000 s. It shows similar performance at different repeated bending angles (0° to 180°) and continuous bending along with long cycle life. The application of the battery is also investigated for printable and wearable textile applications. Therefore, this printable, flexible, easily processable, and nontoxic battery with this performance has great potential to be used in portable and wearable textile electronics.
1. VIEW OF EAST FRONT OF BREAKER, WITH SCALE STICK, ...
1. VIEW OF EAST FRONT OF BREAKER, WITH SCALE STICK, SHOWING FOUNDATIONS OF RETAIL SCALES IN FOREGROUND, LOOKING WEST - Marvine Colliery, Breaker No. 2, West side Boulevard Avenue, between East Parker Street & Route 380, Scranton, Lackawanna County, PA
1987-09-17
T. J. Watson Research Center, Yorktown Heights, N.Y. 10598 Processing, design , and characterization issues are discussed for advanced field-effect...Graded-gate FET (GFET) Jan. 1969. designed to overcome these problems, was presented. The differential gate bias allows control [3] D. Misra, T.R...structure, the degree of freedom in zation [7) of the partially restricted active circuit or system design circuit layout, and area is to control the
Reproducible and controllable induction voltage adder for scaled beam experiments
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sakai, Yasuo; Nakajima, Mitsuo; Horioka, Kazuhiko
2016-08-15
A reproducible and controllable induction adder was developed using solid-state switching devices and Finemet cores for scaled beam compression experiments. A gate controlled MOSFET circuit was developed for the controllable voltage driver. The MOSFET circuit drove the induction adder at low magnetization levels of the cores which enabled us to form reproducible modulation voltages with jitter less than 0.3 ns. Preliminary beam compression experiments indicated that the induction adder can improve the reproducibility of modulation voltages and advance the beam physics experiments.
A superconducting direct-current limiter with a power of up to 8 MVA
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fisher, L. M.; Alferov, D. F., E-mail: DFAlferov@niitfa.ru; Akhmetgareev, M. R.
2016-12-15
A resistive switching superconducting fault current limiter (SFCL) for DC networks with a nominal voltage of 3.5 kV and a nominal current of 2 kA was developed, produced, and tested. The SFCL has two main units—an assembly of superconducting modules and a high-speed vacuum circuit breaker. The assembly of superconducting modules consists of nine (3 × 3) parallel–series connected modules. Each module contains four parallel-connected 2G high-temperature superconducting (HTS) tapes. The results of SFCL tests in the short-circuit emulation mode with a maximum current rise rate of 1300 A/ms are presented. The SFCL is capable of limiting the current atmore » a level of 7 kA and break it 8 ms after the current-limiting mode begins. The average temperature of HTS tapes during the current-limiting mode increases to 210 K. After the current is interrupted, the superconductivity recovery time does not exceed 1 s.« less
A superconducting direct-current limiter with a power of up to 8 MVA
NASA Astrophysics Data System (ADS)
Fisher, L. M.; Alferov, D. F.; Akhmetgareev, M. R.; Budovskii, A. I.; Evsin, D. V.; Voloshin, I. F.; Kalinov, A. V.
2016-12-01
A resistive switching superconducting fault current limiter (SFCL) for DC networks with a nominal voltage of 3.5 kV and a nominal current of 2 kA was developed, produced, and tested. The SFCL has two main units—an assembly of superconducting modules and a high-speed vacuum circuit breaker. The assembly of superconducting modules consists of nine (3 × 3) parallel-series connected modules. Each module contains four parallel-connected 2G high-temperature superconducting (HTS) tapes. The results of SFCL tests in the short-circuit emulation mode with a maximum current rise rate of 1300 A/ms are presented. The SFCL is capable of limiting the current at a level of 7 kA and break it 8 ms after the current-limiting mode begins. The average temperature of HTS tapes during the current-limiting mode increases to 210 K. After the current is interrupted, the superconductivity recovery time does not exceed 1 s.
In Situ Neutron Depth Profiling of Lithium Metal-Garnet Interfaces for Solid State Batteries.
Wang, Chengwei; Gong, Yunhui; Dai, Jiaqi; Zhang, Lei; Xie, Hua; Pastel, Glenn; Liu, Boyang; Wachsman, Eric; Wang, Howard; Hu, Liangbing
2017-10-11
The garnet-based solid state electrolyte (SSE) is considered a promising candidate to realize all solid state lithium (Li) metal batteries. However, critical issues require additional investigation before practical applications become possible, among which high interfacial impedance and low interfacial stability remain the most challenging. In this work, neutron depth profiling (NDP), a nondestructive and uniquely Li-sensitive technique, has been used to reveal the interfacial behavior of garnet SSE in contact with metallic Li through in situ monitoring of Li plating-stripping processes. The NDP measurement demonstrates predictive capabilities for diagnosing short-circuits in solid state batteries. Two types of cells, symmetric Li/garnet/Li (LGL) cells and asymmetric Li/garnet/carbon-nanotubes (LGC), are fabricated to emulate the behavior of Li metal and Li-free Li metal anodes, respectively. The data imply the limitation of Li-free Li metal anode in forming reliable interfacial contacts, and strategies of excessive Li and better interfacial engineering need to be investigated.
Silva, Alessandro Jose Nunes da; Almeida, Ildeberto Muniz de; Vilela, Rodolfo Andrade de Gouveia; Mendes, Renata Wey Berti; Hurtado, Sandra Lorena Beltran
2018-05-10
The Brazilian electricity sector has recorded high work-related mortality rates that have been associated with outsourcing, used to cut costs. In order to decrease the power outage time for consumers, the industry adopted the automatic circuit recloser as the technical solution. The device has hazardous implications for maintenance workers. The aim of this study was to analyze the origins and consequences of work accidents in power systems with automatic circuit recloser, using the Accident Analysis and Prevention (AAP) model. The AAP model was used to investigate two work accidents, aimed to explore the events' organizational origins. Case 1 - when changing a deenergized secondary line, a worker received a shock from the energized primary cable (13.8kV). The system reclosed three times, causing severe injury to the worker (amputation of a lower limb). Case 2 - a fatal work accident occurred during installation of a new crosshead on a partially insulated energized line. The tip of a metal cross arm section strap touched the energized secondary line and electrocuted the maintenance operator. The circuit breaker component of the automatic circuit recloser failed. The analyses revealed how business management logic can participate in the root causes of work accidents through failures in maintenance management, outsourced workforce management, and especially safety management in systems with reclosers. Decisions to adopt automation to guarantee power distribution should not overlook the risks to workers in overhead power lines or fail to acknowledge the importance of ensuring safe conditions.
Detail of field breakers in the motor control cabinet for ...
Detail of field breakers in the motor control cabinet for unit 3. Control cabinet and breaker panel built by Cutler-Hammer - Wellton-Mohawk Irrigation System, Pumping Plant No. 1, Bounded by Gila River & Union Pacific Railroad, Wellton, Yuma County, AZ
47. Northwest Side of Breaker, Rock Belt Line (foreground), date ...
47. Northwest Side of Breaker, Rock Belt Line (foreground), date unknown Historic Photograph, Photograher Unknown; Collection of William Everett, Jr. (Wilkes-Barre, PA), photocopy by Joseph E.B. Elliot - Huber Coal Breaker, 101 South Main Street, Ashley, Luzerne County, PA
Vision based speed breaker detection for autonomous vehicle
NASA Astrophysics Data System (ADS)
C. S., Arvind; Mishra, Ritesh; Vishal, Kumar; Gundimeda, Venugopal
2018-04-01
In this paper, we are presenting a robust and real-time, vision-based approach to detect speed breaker in urban environments for autonomous vehicle. Our method is designed to detect the speed breaker using visual inputs obtained from a camera mounted on top of a vehicle. The method performs inverse perspective mapping to generate top view of the road and segment out region of interest based on difference of Gaussian and median filter images. Furthermore, the algorithm performs RANSAC line fitting to identify the possible speed breaker candidate region. This initial guessed region via RANSAC, is validated using support vector machine. Our algorithm can detect different categories of speed breakers on cement, asphalt and interlock roads at various conditions and have achieved a recall of 0.98.
Adaptation of ion beam technology to microfabrication of solid state devices and transducers
NASA Technical Reports Server (NTRS)
Topich, J. A.
1978-01-01
A number of areas were investigated to determine the potential uses of ion beam techniques in the construction of solid state devices and transducers and the packaging of implantable electronics for biomedical applications. The five areas investigated during the past year were: (1) diode-like devices fabricated on textured silicon; (2) a photolithographic technique for patterning ion beam sputtered PVC (polyvinyl chloride); (3) use of sputtered Teflon as a protective coating for implantable pressure sensors; (4) the sputtering of Macor to seal implantable hybrid circuits; and (5) the use of sputtered Teflon to immobilize enzymes.
NASA Technical Reports Server (NTRS)
1991-01-01
Optoelectronic materials and devices are examined. Optoelectronic devices, which generate, detect, modulate, or switch electromagnetic radiation are being developed for a variety of space applications. The program includes spatial light modulators, solid state lasers, optoelectronic integrated circuits, nonlinear optical materials and devices, fiber optics, and optical networking photovoltaic technology and optical processing.
Flexible packaging of solid-state integrated circuit chips with elastomeric microfluidics
Zhang, Bowei; Dong, Quan; Korman, Can E.; Li, Zhenyu; Zaghloul, Mona E.
2013-01-01
A flexible technology is proposed to integrate smart electronics and microfluidics all embedded in an elastomer package. The microfluidic channels are used to deliver both liquid samples and liquid metals to the integrated circuits (ICs). The liquid metals are used to realize electrical interconnects to the IC chip. This avoids the traditional IC packaging challenges, such as wire-bonding and flip-chip bonding, which are not compatible with current microfluidic technologies. As a demonstration we integrated a CMOS magnetic sensor chip and associate microfluidic channels on a polydimethylsiloxane (PDMS) substrate that allows precise delivery of small liquid samples to the sensor. Furthermore, the packaged system is fully functional under bending curvature radius of one centimetre and uniaxial strain of 15%. The flexible integration of solid-state ICs with microfluidics enables compact flexible electronic and lab-on-a-chip systems, which hold great potential for wearable health monitoring, point-of-care diagnostics and environmental sensing among many other applications.
An Analysis of Transient Overvoltages during the Energization of Electric Ship Propulsion Systems
Brenna, Morris; Foiadelli, Federica; Zaninelli, Dario
2015-01-01
This paper addresses the resonance phenomena that can occur in an isolated distribution system during transient events such as repeated energizations or power converter switching. In particular, the aim of this study is to analyze the energization of an onboard radial distribution system installed on an electric ship and to determine how the various leakage parameters that can cause resonance problems such as high peak overvoltages when the circuit breaker is closed are relevant. The paper presents a detailed model of whole distribution system, which is validated using infield measurements that refer to a real case in which these events damaged the ships transformers, causing it to be removed from duty. PMID:26240835
Solid-state single-photon emitters
NASA Astrophysics Data System (ADS)
Aharonovich, Igor; Englund, Dirk; Toth, Milos
2016-10-01
Single-photon emitters play an important role in many leading quantum technologies. There is still no 'ideal' on-demand single-photon emitter, but a plethora of promising material systems have been developed, and several have transitioned from proof-of-concept to engineering efforts with steadily improving performance. Here, we review recent progress in the race towards true single-photon emitters required for a range of quantum information processing applications. We focus on solid-state systems including quantum dots, defects in solids, two-dimensional hosts and carbon nanotubes, as these are well positioned to benefit from recent breakthroughs in nanofabrication and materials growth techniques. We consider the main challenges and key advantages of each platform, with a focus on scalable on-chip integration and fabrication of identical sources on photonic circuits.
NASA Astrophysics Data System (ADS)
McQuiddy, David N., Jr.; Sokolov, Vladimir
1990-12-01
The present conference discusses microwave filters, lightwave technology for microwave antennas, planar and quasi-planar guides, mixers and VCOs, cavity filters, discontinuity and coupling effects, control circuits, power dividers and phase shifters, microwave ICs, biological effects and medical applications, CAD and modeling for MMICs, directional couplers, MMIC design trends, microwave packaging and manufacturing, monolithic ICs, and solid-state devices and circuits. Also discussed are microwave and mm-wave superconducting technology, MICs for communication systems, the merging of optical and microwave technologies, microwave power transistors, ferrite devices, network measurements, advanced transmission-line structures, FET devices and circuits, field theory of IC discontinuities, active quasi-optical techniques, phased-array techniques and circuits, nonlinear CAD, sub-mm wave devices, and high power devices.
The ringer - An efficient, high repetition rate circuit for electromagnetic launchers
NASA Astrophysics Data System (ADS)
Giorgi, D.; Helava, H.; Lindner, K.; Long, J.; Zucker, O.
1989-01-01
The Meatgrinder is an efficient, current-multiplying circuit which can be used to optimize the energy transfer to various electromagnetic gun configurations. The authors present a simple variant of the Meatgrinder circuit which permits a first-order current profiling into the gun and recovery of the inductive energy in the barrel at a high repetition rate. The circuit is basically a one-stage Meatgrinder which utilizes the ringing of the energy storage capacitor (less than 40 percent reversal) to perform the opening switch function and a solid-state diode as the crowbar switch between the two mutually coupled inductors. With resonant charging, this results in a completely passive, high-repetiton-rate electromagnetic-gun power supply. Since most of the barrel energy is recovered, a railgun with negligible muzzle flash can be realized.