Sample records for ac power voltage

  1. High frequency AC power converter for low voltage circuits

    E-Print Network [OSTI]

    Salazar, Nathaniel Jay Tobias

    2012-01-01T23:59:59.000Z

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

  2. Design and analysis of modern three-phase AC/AC power converters for AC drives and utility interface 

    E-Print Network [OSTI]

    Kwak, Sangshin

    2005-08-29T23:59:59.000Z

    Significant advances in modern ac/ac power converter technologies and demands of industries have reached beyond standard ac/ac power converters with voltage-source inverters fed from diode rectifiers. Power electronics converters have been matured...

  3. Design of a Solid-State Fast Voltage Compensator for klystron modulators requiring constant AC power consumption

    E-Print Network [OSTI]

    Davide, Aguglia; Philippe, Viarouge; Jerome, Cros

    2015-01-01T23:59:59.000Z

    This paper proposes a novel topological solution for klystron modulators integrating a Fast Voltage Compensator which allows an operation at constant power consumption from the utility grid. This kind of solution is mandatory for the CLIC project under study, which requires several hundreds of synchronously operated klystron modulators for a total pulsed power of 39 GW. The topology is optimized for the challenging CLIC specifications, which require a very precise output voltage flat-top as well as fast rise and fall times (3µs). The Fast Voltage Compensator is integrated in the modulator such that it only has to manage the capacitor charger current and a fraction of the charging voltage. Consequently, its dimensioning power and cost is minimized.

  4. 82 IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS, PART 1, VOL. 47, NO. 1, JANUARY 2000 Fig. 5. Output voltage waveform in the closed-loop dc-ac power inverter.

    E-Print Network [OSTI]

    Leuciuc, Adrian

    voltage waveform in the closed-loop dc-ac power inverter. Horizontal scale: 5 ms/div.; vertical scale: 0.2 V/div. Fig. 6. Bode plots of the closed-loop power inverter . Packard 4194A Network Analyzer, Bode that the -3-dB frequency was 205 Hz. IV. CONCLUSION This study demonstrates that a low-frequency dc-ac power

  5. High voltage DC power supply

    DOE Patents [OSTI]

    Droege, Thomas F. (Batavia, IL)

    1989-01-01T23:59:59.000Z

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

  6. High voltage DC power supply

    DOE Patents [OSTI]

    Droege, T.F.

    1989-12-19T23:59:59.000Z

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

  7. Voltage CollapseVoltage Collapse Animation (AC)Animation (AC)

    E-Print Network [OSTI]

    power (or VARs) to their local loads plus VARs to the transmission lines to support the transfer) where the generators, loads and transmission lines interconnect · Transmission lines: lines connecting · Circuit breakers: red boxes · Line flows: arrows on the transmission lines (more easily seen in the last

  8. Voltage, energy and power in electric circuits

    E-Print Network [OSTI]

    Berzins, M.

    Voltage, energy and power in electric circuits Science teaching unit #12;Disclaimer The Department-2008DVD-EN Voltage, energy and power in electric circuits #12;#12;© Crown copyright 2008 1The National Strategies | Secondary Voltage, energy and power in electric circuits 00094-2008DVD-EN Contents Voltage

  9. Strongly nonlinear dynamics of electrolytes in large ac voltages

    E-Print Network [OSTI]

    Hojgaard Olesen, Laurits

    We study the response of a model microelectrochemical cell to a large ac voltage of frequency comparable to the inverse cell relaxation time. To bring out the basic physics, we consider the simplest possible model of a ...

  10. AC and DC power transmission

    SciTech Connect (OSTI)

    Not Available

    1985-01-01T23:59:59.000Z

    The technical and economic assessment of AC and DC transmission systems; long distance transmission, cable transmission, system inter-connection, voltage support, reactive compensation, stabilisation of systems; parallel operation of DC links with AC systems; comparison between alternatives for particular schemes. Design and application equipment: design, testing and application of equipment for HVDC, series and shunt static compensated AC schemes, including associated controls. Installations: overall design of stations and conductor arrangements for HVDC, series and shunt static AC schemes including insulation co-ordination. System analysis and modelling.

  11. Optimal Power Flow Incorporating Voltage Collapse Constraints

    E-Print Network [OSTI]

    Cañizares, Claudio A.

    Optimal Power Flow Incorporating Voltage Collapse Constraints William Rosehart Claudio Ca on the current operating con- ditions is presented. Second, an Optimal Power Flow formulation that incorporates: Voltage Collapse, Optimal Power Flow, Bifur- cations. I. Introduction As open-access market principles

  12. Wind Power Plant Voltage Stability Evaluation: Preprint

    SciTech Connect (OSTI)

    Muljadi, E.; Zhang, Y. C.

    2014-09-01T23:59:59.000Z

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

  13. Electrical Circuit Flashover Model of Polluted Insulators under AC Voltage Based on the Arc Root Voltage Gradient Criterion

    E-Print Network [OSTI]

    Yang, Qing

    In order to study the flashover mechanism of polluted insulators under AC voltage, a new arc propagation criterion which is based on an arc root voltage gradient is proposed. This criterion can explain the variation of the ...

  14. Local Dynamic Reactive Power for Correction of System Voltage Problems

    SciTech Connect (OSTI)

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

    2008-12-01T23:59:59.000Z

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

  15. Low power, scalable multichannel high voltage controller

    DOE Patents [OSTI]

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

    2008-03-25T23:59:59.000Z

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

  16. Low power, scalable multichannel high voltage controller

    DOE Patents [OSTI]

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

    2006-03-14T23:59:59.000Z

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

  17. High voltage photovoltaic power converter

    DOE Patents [OSTI]

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

    2001-01-01T23:59:59.000Z

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

  18. Marine High Voltage Power Conditioning and Transmission System with Integrated Storage DE-EE0003640 Final Report

    SciTech Connect (OSTI)

    Frank Hoffmann, PhD; Aspinall, Rik

    2012-12-10T23:59:59.000Z

    Design, Development, and test of the three-port power converter for marine hydrokinetic power transmission. Converter provides ports for AC/DC conversion of hydrokinetic power, battery storage, and a low voltage to high voltage DC port for HVDC transmission to shore. The report covers the design, development, implementation, and testing of a prototype built by PPS.

  19. A three-level buck converter to regulate a high-voltage DC-to-AC inverter

    E-Print Network [OSTI]

    Schrock, Kenneth C

    2008-01-01T23:59:59.000Z

    A three-level buck converter is designed and analyzed, and shown to be suitable as a high-voltage down converter as a pre-regulation stage for a 600 watt DC-to-AC power inverter. Topology selection for the inverter is ...

  20. Modular high voltage power supply for chemical analysis

    DOE Patents [OSTI]

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

    2010-05-04T23:59:59.000Z

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

  1. Modular high voltage power supply for chemical analysis

    SciTech Connect (OSTI)

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

    2007-01-09T23:59:59.000Z

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

  2. Modular high voltage power supply for chemical analysis

    SciTech Connect (OSTI)

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

    2008-07-15T23:59:59.000Z

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

  3. * jafleeman@aep.com EHV AC and HVDC Transmission Working Together to Integrate Renewable Power

    E-Print Network [OSTI]

    McCalley, James D.

    * jafleeman@aep.com EHV AC and HVDC Transmission Working Together to Integrate Renewable Power J. A current (EHV AC) and high voltage direct current (HVDC) transmission systems and advocates a hybrid as a high capacity platform for system integration. HVDC transmission offers express, efficient delivery

  4. High-Power Converters and AC Drives IEEE PESC2005 Tutorial

    E-Print Network [OSTI]

    Wu, Bin

    @ee.ryerson.ca http://www.ee.ryerson.ca/~bwu/ 2 High-Power Converters and AC Drives 1. Introduction 2. Cascaded H-Bridge Drives · High-Power Semiconductor Devices High-Power Converters and AC Drives Bin Wu 4High · Multilevel Voltage Source Inverters N dC Cascaded H-bridge (CHB) Inverter dC Two Level Inverter dC Flying

  5. Submerged Medium Voltage Cable Systems at Nuclear Power Plants...

    Office of Scientific and Technical Information (OSTI)

    Submerged Medium Voltage Cable Systems at Nuclear Power Plants: A Review of Research Efforts Relevant to Aging Mechanisms and Condition Monitoring. Re-direct Destination: In a...

  6. Switch contact device for interrupting high current, high voltage, AC and DC circuits

    DOE Patents [OSTI]

    Via, Lester C.; Witherspoon, F. Douglas; Ryan, John M.

    2005-01-04T23:59:59.000Z

    A high voltage switch contact structure capable of interrupting high voltage, high current AC and DC circuits. The contact structure confines the arc created when contacts open to the thin area between two insulating surfaces in intimate contact. This forces the arc into the shape of a thin sheet which loses heat energy far more rapidly than an arc column having a circular cross-section. These high heat losses require a dramatic increase in the voltage required to maintain the arc, thus extinguishing it when the required voltage exceeds the available voltage. The arc extinguishing process with this invention is not dependent on the occurrence of a current zero crossing and, consequently, is capable of rapidly interrupting both AC and DC circuits. The contact structure achieves its high performance without the use of sulfur hexafluoride.

  7. E-beam high voltage switching power supply

    DOE Patents [OSTI]

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

    1996-10-15T23:59:59.000Z

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

  8. E-beam high voltage switching power supply

    DOE Patents [OSTI]

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

    1996-01-01T23:59:59.000Z

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

  9. An Annotated Bibliography of High-Voltage Direct-Current Transmission and Flexible AC Transmission (FACTS) Devices, 1991-1993.

    SciTech Connect (OSTI)

    Litzenberger, Wayne; Lava, Val

    1994-08-01T23:59:59.000Z

    References are contained for HVDC systems, converter stations and components, overhead transmission lines, cable transmission, system design and operations, simulation of high voltage direct current systems, high-voltage direct current installations, and flexible AC transmission system (FACTS).

  10. Power Grid Voltage Integrity Verification Department of ECE

    E-Print Network [OSTI]

    Najm, Farid N.

    Power Grid Voltage Integrity Verification Maha Nizam Department of ECE University of Toronto devgan@magma-da.com ABSTRACT Full-chip verification requires one to check if the power grid is safe, i.e., if the voltage drop on the grid does not exceed a cer- tain threshold. The traditional simulation-based solution

  11. ac voltage standard: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    in the paper can be used in engineering designs. I. INTRODUCTION Piezoelectric Transformers (PT) convert electric power into electric power via a mechanical resonant link....

  12. VOLTAGE COLLAPSE AND TRANSIENT ENERGY FUNCTION ANALYSES OF AC/DC SYSTEMS

    E-Print Network [OSTI]

    Cañizares, Claudio A.

    for power system dynamic models, including a third order representation of high voltage direct current (HVDC power limits, HVDC firing angle limits and voltage dependent current order limits (VDCOL) are shown the derivation of individual component Lyapunov functions for simplified models of HVDC links connected

  13. A system for tranmitting low frequency analog signals over ac power lines

    DOE Patents [OSTI]

    Baker, S.P.; Durall, R.L.; Haynes, H.D.

    1987-07-30T23:59:59.000Z

    A system for transmitting low frequency analog signals over ac power lines using FM modulation. A low frequency analog signal to be transmitted is first applied to a voltage-to-frequency converter where it is converted to a signal whose frequency varies in proportion to the analog signal amplitude. This signal is then used to modulate the carrier frequency of an FM transmitter coupled to an ac power line. The modulation signal frequency range is selected to be within the response band of the FM transmitter. The FM modulated carrier signal is received by an FM receiver coupled to the ac power line, demodulated and the demodulated signal frequency is converted by a frequency-to-voltage converter back to the form of the original low frequency analog input signal. 4 figs.

  14. THREE DIMENSIONAL VISUALIZATIONS FOR POWER SYSTEM CONTINGENCY ANALYSIS VOLTAGE DATA

    E-Print Network [OSTI]

    that the power systems are now often operated closer to their limits to maximum transmission system utilizationTHREE DIMENSIONAL VISUALIZATIONS FOR POWER SYSTEM CONTINGENCY ANALYSIS VOLTAGE DATA Y. Sun IEEE security assessment is critical for detecting underlying problems in a power system. More frequent CA

  15. Memory Power Management via Dynamic Voltage/Frequency Scaling

    E-Print Network [OSTI]

    McGaughey, Alan

    years. In the data center environment, thermal management and power budgeting have become significant transitions [10, 23], or scal- ing active server power proportionally to load [2]. In this paper, we focusMemory Power Management via Dynamic Voltage/Frequency Scaling Howard David, Chris Fallin§, Eugene

  16. Memory Power Management via Dynamic Voltage/Frequency Scaling

    E-Print Network [OSTI]

    Mutlu, Onur

    years. In the data center environment, thermal management and power budgeting have become significant sleep transitions [10, 23], or scal- ing active server power proportionally to load [2]. In this paperMemory Power Management via Dynamic Voltage/Frequency Scaling Howard David, Chris Fallin§, Eugene

  17. Contribution Allocation for Voltage Stability In Deregulated Power Systems

    E-Print Network [OSTI]

    Contribution Allocation for Voltage Stability In Deregulated Power Systems Garng M. Huang, Senior, stability margin I. INTRODUCTION The deregulated power system is based on transactions; each part Member, IEEE, Kun Men Abstract: With deregulation of power systems, it is of great importance to know who

  18. E-beam high voltage switching power supply

    DOE Patents [OSTI]

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

    1997-01-01T23:59:59.000Z

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

  19. E-beam high voltage switching power supply

    DOE Patents [OSTI]

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

    1997-03-11T23:59:59.000Z

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

  20. An improved voltage control on large-scale power system

    SciTech Connect (OSTI)

    Vu, H.; Pruvot, P.; Launay, C.; Harmand, Y. [Electricite de France, Clamart (France). Study and Research Div.] [Electricite de France, Clamart (France). Study and Research Div.

    1996-08-01T23:59:59.000Z

    To achieve a better voltage-var control in the electric power transmission system, different facilities are used. Generators are equipped with automatic voltage regulators to cope with sudden and random changes voltage caused by natural load fluctuations or failures. Other devices like capacitors, inductors, transformers with on load tap changers are installed on the network. Faced with the evolution of the network and operating conditions, electricity utilities are more and more interested in overall and coherent control systems, automatic or not. These systems are expected to coordinate the actions of local facilities for a better voltage control (more stable and faster reaction) inside different areas of the network in case of greater voltage and var variations. They affords besides a better use of existing reactive resources. Also, installation of new devices can be avoided allowing economy of investment. With this frame of mind, EDF has designed a system called Co-ordinated Secondary Voltage Control (CSVC). It`s an automatic closed loop system with a dynamic of a few minutes. It takes into account the network conditions (topology, loads), the voltage limits and the generator operating constraints. This paper presents recent improvements which allow the CSVC to control the voltage profile and different kinds of reactive means on a large-scale power system. Furthermore, this paper presents solution to spread out investment costs over several years, considering a deployment gradually extended.

  1. Princeton Power Systems (TRL 5 6 Component)- Marine High-Voltage Power Conditioning and Transmission System with Integrated Energy Storage

    Broader source: Energy.gov [DOE]

    Princeton Power Systems (TRL 5 6 Component) - Marine High-Voltage Power Conditioning and Transmission System with Integrated Energy Storage

  2. Bi-directional power control system for voltage converter

    DOE Patents [OSTI]

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

    1999-05-11T23:59:59.000Z

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

  3. Bi-directional power control system for voltage converter

    DOE Patents [OSTI]

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

    1999-01-01T23:59:59.000Z

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

  4. Intelligent Voltage and Reactive Power Control of Mini-Hydro Power Stations for Maximisation of Real

    E-Print Network [OSTI]

    Harrison, Gareth

    1 Intelligent Voltage and Reactive Power Control of Mini-Hydro Power Stations for Maximisation Control (APFC) modes. The ability to export active and reactive power from mini-hydro power generators electrical power generation from renewable resources. Additionally, the potential early retiral of central

  5. Programmable AC power supply for simulating power transient expected in fusion reactor

    SciTech Connect (OSTI)

    Halimi, B. [Seoul National Univ., Seoul 151-744 (Korea, Republic of); Suh, K. Y. [Seoul National Univ., Seoul 151-744 (Korea, Republic of); PHILOSOPHIA, 1 Gwanak Ro, Gwanak Gu, Seoul 151-744 (Korea, Republic of)

    2012-07-01T23:59:59.000Z

    This paper focus on control engineering of the programmable AC power source which has capability to simulate power transient expected in fusion reactor. To generate the programmable power source, AC-AC power electronics converter is adopted to control the power of a set of heaters to represent the transient phenomena of heat exchangers or heat sources of a fusion reactor. The International Thermonuclear Experimental Reactor (ITER) plasma operation scenario is used as the basic reference for producing this transient power source. (authors)

  6. Assessment of research directions for high-voltage direct-current power systems. Final report

    SciTech Connect (OSTI)

    Long, W F

    1982-09-01T23:59:59.000Z

    High voltage direct current (HVDC) power transmission continues to be an emerging technology nearly thirty years after its introduction into modern power systems. To date its use has been restricted to either specialized applications having identifiable economic advantages (e.g., breakeven distance) or, rarely, applications where decoupling is needed. Only recently have the operational advantages (e.g., power modulation) of HVDC been realized on operating systems. A research project whose objective was to identify hardware developments and, where appropriate, system applications which can exemplify cost and operational advantages of integrated ac/dc power systems is discussed. The three principal tasks undertaken were: assessment of equipment developments; quantification of operational advantages; and interaction with system planners. Interest in HVDC power transmission has increased markedly over the past several years, and many new systems are now being investigated. The dissemination of information about HVDC, including specifically the symposium undertaken for Task 3, is a critical factor in fostering an understanding of this important adjunct to ac power transmission.

  7. Multi-objective Optimal Power Flows to Evaluate Voltage Security Costs in Power Networks

    E-Print Network [OSTI]

    Cañizares, Claudio A.

    1 Multi-objective Optimal Power Flows to Evaluate Voltage Security Costs in Power Networks William Abstract-- In this paper, new optimal power flow (OPF) tech- niques are proposed based on multi- dard power flow models. The results obtained using the proposed mixed OPFs are compared and analyzed

  8. PAPER ACCEPTED TO IEEE TRANSACTIONS ON POWER SYSTEMS, Nov. 2008 1 Reactive Power and Voltage Control in Distribution

    E-Print Network [OSTI]

    Cañizares, Claudio A.

    PAPER ACCEPTED TO IEEE TRANSACTIONS ON POWER SYSTEMS, Nov. 2008 1 Reactive Power and Voltage) problem associated with reactive power and voltage control in distribution systems to minimize daily--Distribution systems, reactive power control, voltage control, optimal switching operations, mixed integer nonlinear

  9. Probabilistic Vulnerability Assessment Based on Power Flow and Voltage Distribution

    SciTech Connect (OSTI)

    Ma, Jian; Huang, Zhenyu; Wong, Pak C.; Ferryman, Thomas A.

    2010-04-30T23:59:59.000Z

    Risk assessment of large scale power systems has been an important problem in power system reliability study. Probabilistic technique provides a powerful tool to solve the task. In this paper, we present the results of a study on probabilistic vulnerability assessment on WECC system. Cumulant based expansion method is applied to obtain the probabilistic distribution function (PDF) and cumulative distribution function (CDF) of power flows on transmission lines and voltage. Overall risk index based on the system vulnerability analysis is calculated using the WECC system. The simulation results based on WECC system is used to demonstrate the effectiveness of the method. The methodology can be applied to the risk analysis on large scale power systems.

  10. Interline photovoltaic (I-PV) power plants for voltage unbalance compensation

    E-Print Network [OSTI]

    Moawwad, Ahmed

    This paper proposes a stationary-frame control method for voltage unbalance compensation using Interline Photovoltaic (I-PV) power system. I-PV power systems are controlled to compensate voltage unbalance autonomously. The ...

  11. Measurement based Voltage Stability Monitoring of Power system Garng M. Huang

    E-Print Network [OSTI]

    Measurement based Voltage Stability Monitoring of Power system Garng M. Huang huang Station, TX 77843-3128 Abstract: Many papers discuss the voltage stability assessment of power system. The problem of voltage stability may be simply explained as inability of the power system to provide

  12. Static reactive power compensators for high-voltage power systems. Final report

    SciTech Connect (OSTI)

    Not Available

    1981-04-01T23:59:59.000Z

    A study conducted to summarize the role of static reactive power compensators for high voltage power system applications is described. This information should be useful to the utility system planning engineer in applying static var systems (SVS) to high voltage as (HVAC) systems. The static var system is defined as a form of reactive power compensator. The general need for reactive power compensation in HVAC systems is discussed, and the static var system is compared to other devices utilized to provide reactive power compensation. Examples are presented of applying SVS for specific functions, such as the prevention of voltage collapse. The operating principles of commercially available SVS's are discussed in detail. The perormance and active power loss characteristics of SVS types are compared.

  13. DIII-D ICRF high voltage power supply regulator upgrade

    SciTech Connect (OSTI)

    Cary, W.P.; Burley, B.L.; Grosnickle, W.H.

    1997-11-01T23:59:59.000Z

    For reliable operation and component protection, of the 2 MW 30--120 MHz ICRF Amplifier System on DIII-D, it is desirable for the amplifier to respond to high VSWR conditions as rapidly as possible. This requires a rapid change in power which also means a rapid change in the high voltage power supply current demands. An analysis of the power supply`s regulator dynamics was needed to verify its expected operation during such conditions. Based on this information it was found that a new regulator with a larger dynamic range and some anticipation capability would be required. This paper will discuss the system requirements, the as-delivered regulator performance, and the improved performance after installation of the new regulator system. It will also be shown how this improvement has made the amplifier perform at higher power levels more reliably.

  14. Power conditioning system for energy sources

    DOE Patents [OSTI]

    Mazumder, Sudip K. (Chicago, IL); Burra, Rajni K. (Chicago, IL); Acharya, Kaustuva (Chicago, IL)

    2008-05-13T23:59:59.000Z

    Apparatus for conditioning power generated by an energy source includes an inverter for converting a DC input voltage from the energy source to a square wave AC output voltage, and a converter for converting the AC output voltage from the inverter to a sine wave AC output voltage.

  15. Nonlinear modal interaction in HVDC/AC power systems with dc power modulation

    SciTech Connect (OSTI)

    Ni, Y.X. [Tsinghua Univ., Beijing (China)] [Tsinghua Univ., Beijing (China); Vittal, V.; Kliemann, W.; Fouad, A.A. [Iowa State Univ., Ames, IA (United States)] [Iowa State Univ., Ames, IA (United States)

    1996-11-01T23:59:59.000Z

    In this paper investigation of nonlinear modal interaction using the normal form of vector fields technique is extended to HVDC/AC power systems with dc power modulation. The ac-dc interface equations are solved to form a state space model with second order approximation. Using the normal form technique, the system`s nonlinear dynamic characteristics are obtained. The proposed approach is applied to a 4-generator HVDC/AC test power system, and compare with the time domain solution.

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

    E-Print Network [OSTI]

    Bellan, Paul M.

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

  17. Rotating electrical machines - Part 15: Impulse voltage withstand levels of rotating a.c. machines with form-wound stator coils

    E-Print Network [OSTI]

    International Electrotechnical Commission. Geneva

    1995-01-01T23:59:59.000Z

    Applies to rotating a.c. machines for rated voltages from 3 kV to 15 kV inclusive and incorporating form-wound stator coils. Specifies the rated phase-to-earth impulse voltage withstand levels and the test procedure and voltages to be applied to the main and interturn insulation of sample coils.

  18. Public Opinions of Building Additional High-Voltage Electric Power Lines

    E-Print Network [OSTI]

    Tesfatsion, Leigh

    Public Opinions of Building Additional High-Voltage Electric Power Lines A Report to the National-Voltage Electric Power Lines: A Report to the National Science Foundation and the Electric Power Research Center to build new power lines. Residents living in counties with planned routes for new transmission lines

  19. Importance of the Equlibrium Node in Preventing the Voltage Collapse Occurs in the Wind Power System

    E-Print Network [OSTI]

    Lavaei, Javad

    Importance of the Equlibrium Node in Preventing the Voltage Collapse Occurs in the Wind Power collapse will occurs in a wind power system is discussed next. The method of power flow calculation is the specific analysis of a given simplified wind power system. Keywords--voltage collapse; Newton

  20. Capturing power at higher voltages from arrays of microbial fuel cells without voltage reversal

    E-Print Network [OSTI]

    is too low to be used directly for many practical applications. For example, a single light emitting diode (LED) requires a minimum voltage of 2 V.2 Thus, effective methods of boosting MFC voltages

  1. A SCR SWITCHED CAPACITOR VOLTAGE REGULATOR FOR 150 kV NEUTRAL BEAM POWER SUPPLY

    E-Print Network [OSTI]

    Milnes, K.A.

    2011-01-01T23:59:59.000Z

    et a1. , "150-kV, 80-A Solid State Power Supply for Neutral100% solid state and provides 1% regulation at power levelssolid state high voltage re- gulator. The block diagram of the power

  2. ac to dc converters: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    to use solid state Inverters(DC to AC converters) to have a variable voltage, fixed or variable frequency power source available for industrial applications. With advancements...

  3. Voltage Control of Distribution Networks with Distributed Generation using Reactive Power

    E-Print Network [OSTI]

    Pota, Himanshu Roy

    Voltage Control of Distribution Networks with Distributed Generation using Reactive Power to control voltage of distribution networks with DG using reactive power compensation approach. In this paper profile within the specified limits, it is essential to regulate the reactive power of the compensators

  4. Supervisory hybrid model predictive control for voltage stability of power networks

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Supervisory hybrid model predictive control for voltage stability of power networks R.R. Negenborn voltage control problems in electric power networks have stimulated the interest for the imple- mentation dynamics to restore power consumption beyond the capability of the transmission and generation system

  5. Voltage Stability and Power Quality Issues of Wind Farm with Series Compensation

    E-Print Network [OSTI]

    Pota, Himanshu Roy

    Voltage Stability and Power Quality Issues of Wind Farm with Series Compensation T. F. Orchi generator (DFIG) wind farms with series and shunt compensation are analyzed. The voltage source converter of the wind farm are modeled with flicker coefficients as defined by IEC standard 61400 and voltage sag

  6. The vertical voltage termination technique characterizations of single die multiple 600V power

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    The vertical voltage termination technique ­ characterizations of single die multiple 600V power.grenoble-inp.fr Abstract-- Deep trench terminations are commonly known as a technique to achieve ideal breakdown voltages for high voltage devices. This paper presents the use of deep trench terminations as an original concept

  7. The powerful high-voltage glow discharge electron gun and power unit on its base

    SciTech Connect (OSTI)

    Chernov, V.A. [All-Russian Electrotechnical Institute, Moscow (Russian Federation)

    1994-12-31T23:59:59.000Z

    The technical and operational characteristics and features of powerful electron gun with cold cathodes on the basis of high-voltage glow discharge (HGD) are submitted. The systems, ensuring their work are described. Some results of operation and applications of these non-traditional electron guns are presented.

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

    E-Print Network [OSTI]

    Serdijn, Wouter A.

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

  9. AC power | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItemResearch >InternshipDepartmentNeutrino-Induced1 TEMPERATUREii ABSTRACT ThisAC

  10. High voltage power supply with modular series resonant inverters

    DOE Patents [OSTI]

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

    1995-07-18T23:59:59.000Z

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

  11. High voltage power supply with modular series resonant inverters

    DOE Patents [OSTI]

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

    1995-01-01T23:59:59.000Z

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

  12. Low Power Discrete Voltage Assignment Under Clock Skew , Jian Sun2

    E-Print Network [OSTI]

    Zhou, Hai

    assignment problem by formulating it into an Integer Linear Programming (ILP) with inequalities representingLow Power Discrete Voltage Assignment Under Clock Skew Scheduling Li Li1 , Jian Sun2 , Yinghai Lu1 Abstract--Multiple Supply Voltage (MSV) assignment has emerged as an appealing technique in low power IC

  13. A DSP based real time power quality measurement system with voltage distortion improvement capability 

    E-Print Network [OSTI]

    Gou, Jian

    1992-01-01T23:59:59.000Z

    have been established to specify the limitation on the magnitudes of both harmonic currents and harmonic voltage distortion at different frequencies. Among these the "IEEE Guide for Harmonic Control and Reactive Compensation of Static Power... by the utility and by the electricity consumer has arrived. These measurements include: current and voltage harmonics, input power 1'actor, reactive power, real power, total harmonic distortion (THD), percentage load unbalance, etc. The measured data can...

  14. Minimizing Simultaneous Switching Noise at Reduced Power with Constant-Voltage Power Transmission Lines for High-Speed Signaling

    E-Print Network [OSTI]

    Swaminathan, Madhavan

    plane structure with a power transmission line (PTL). In this paper, a new power delivery scheme called Constant Voltage Power Transmission Line (CV-PTL) is shown to significantly reduce switching noise while, and measurements. Keywords Power delivery network, simultaneous switching noise, power transmission line 1

  15. ePOWER Seminar AC solar cells: A new breed of PV power generation

    E-Print Network [OSTI]

    Abolmaesumi, Purang

    -noon Walter Light Hall, Room 302 Abstract: A solar cell inside a photovoltaic (PV) panel inherently produces ePOWER Seminar AC solar cells: A new breed of PV power generation Professor Faisal Khan Assistant will provide a guideline for solar cell designers to fabricate various discrete components in a power converter

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

    DOE Patents [OSTI]

    Duckworth, Douglas C. (Knoxville, TN); Marcus, R. Kenneth (Clemson, SC); Donohue, David L. (Vienna, AT); Lewis, Trousdale A. (Oak Ridge, TN)

    1994-01-01T23:59:59.000Z

    A high voltage accelerating potential, which is supplied by a high voltage direct current power supply, is applied to the electrically conducting interior wall of an RF powered glow discharge cell. The RF power supply desirably is electrically grounded, and the conductor carrying the RF power to the sample held by the probe is desirably shielded completely excepting only the conductor's terminal point of contact with the sample. The high voltage DC accelerating potential is not supplied to the sample. A high voltage capacitance is electrically connected in series between the sample on the one hand and the RF power supply and an impedance matching network on the other hand. The high voltage capacitance isolates the high DC voltage from the RF electronics, while the RF potential is passed across the high voltage capacitance to the plasma. An inductor protects at least the RF power supply, and desirably the impedance matching network as well, from a short that might occur across the high voltage capacitance. The discharge cell and the probe which holds the sample are configured and disposed to prevent the probe's components, which are maintained at ground potential, from bridging between the relatively low vacuum region in communication with the glow discharge maintained within the cell on the one hand, and the relatively high vacuum region surrounding the probe and cell on the other hand. The probe and cell also are configured and disposed to prevent the probe's components from electrically shorting the cell's components.

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

    DOE Patents [OSTI]

    Duckworth, D.C.; Marcus, R.K.; Donohue, D.L.; Lewis, T.A.

    1994-06-28T23:59:59.000Z

    A high voltage accelerating potential, which is supplied by a high voltage direct current power supply, is applied to the electrically conducting interior wall of an RF powered glow discharge cell. The RF power supply desirably is electrically grounded, and the conductor carrying the RF power to the sample held by the probe is desirably shielded completely excepting only the conductor's terminal point of contact with the sample. The high voltage DC accelerating potential is not supplied to the sample. A high voltage capacitance is electrically connected in series between the sample on the one hand and the RF power supply and an impedance matching network on the other hand. The high voltage capacitance isolates the high DC voltage from the RF electronics, while the RF potential is passed across the high voltage capacitance to the plasma. An inductor protects at least the RF power supply, and desirably the impedance matching network as well, from a short that might occur across the high voltage capacitance. The discharge cell and the probe which holds the sample are configured and disposed to prevent the probe's components, which are maintained at ground potential, from bridging between the relatively low vacuum region in communication with the glow discharge maintained within the cell on the one hand, and the relatively high vacuum region surrounding the probe and cell on the other hand. The probe and cell also are configured and disposed to prevent the probe's components from electrically shorting the cell's components. 11 figures.

  18. Price Discovery in Dynamic Power Markets with Low-Voltage Distribution-Network Participants

    E-Print Network [OSTI]

    Caramanis, Michael

    -distribution network locational marginal prices; power flow; reactive power compensation; voltage control; distributed application to Electric Power [2, 3] dynamic Locational-Marginal-Price (LMP) based Wholesale Power Markets to clear markets and discover dynamic Locational Marginal Prices (LMPs) that promoted more efficient

  19. Effect of Detailed Power System Models in Traditional and Voltage Stability Constrained

    E-Print Network [OSTI]

    Cañizares, Claudio A.

    problems to improve the accuracy of the results. It is shown in [2] that reactive power limits play], [9], [10], it is demonstrated that reactive power limits play a significant role in voltage collapse of power systems. Therefore, particular attention is placed here to the modeling of reactive power limits

  20. 130kV 130A High Voltage Switching Mode Power Supply for Neutral Injections – Control Issues and Algorithms

    E-Print Network [OSTI]

    130kV 130A High Voltage Switching Mode Power Supply for Neutral Injections – Control Issues and Algorithms

  1. Reactive Power Sharing and Voltage Harmonic Distortion Compensation of Droop Controlled

    E-Print Network [OSTI]

    Vasquez, Juan Carlos

    1 Reactive Power Sharing and Voltage Harmonic Distortion Compensation of Droop Controlled Single, the inverters typically employ the droop control scheme. Traditional droop control enables the decentralized regulation of the local voltage and frequency of the microgrid by the inverters. The droop method also

  2. Journal of Power Sources 167 (2007) 1117 Voltage reversal during microbial fuel cell stack operation

    E-Print Network [OSTI]

    2007-01-01T23:59:59.000Z

    Journal of Power Sources 167 (2007) 11­17 Voltage reversal during microbial fuel cell stack February 2007; accepted 9 February 2007 Available online 20 February 2007 Abstract Microbial fuel cells Elsevier B.V. All rights reserved. Keywords: Microbial fuel cell; Voltage reversal; Stack; Direct electron

  3. A New Bifurcation Analysis for Power System Dynamic Voltage Stability Studies

    E-Print Network [OSTI]

    a specific system configuration and the operation condition. For a power system, the typical state variables are the time dependent generator voltages (For different generator models, the variables of generator voltages as the variables of the exciter, speed governor and so on; sometimes the dynamics of the load behavior will also

  4. A LOW POWER SCHEDULING SCHEME WITH RESOURCES OPERATING AT MULTIPLE VOLTAGES

    E-Print Network [OSTI]

    Kambhampati, Subbarao

    A LOW POWER SCHEDULING SCHEME WITH RESOURCES OPERATING AT MULTIPLE VOLTAGES Ali Manzak and Chaitali Tempe, AZ 85287­5706 istanbul@asu.edu, chaitali@asu.edu ABSTRACT This paper presents a new resource the resources operate at multi­ ple voltages. The scheduling scheme is list based. In each control cycle

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

    E-Print Network [OSTI]

    Hadjicostis, Christoforos

    violations and shapes the voltage profile in radial distribution networks, even in the presence [6]--and the Equinox house [7] are examples of residential PV installations capable of producing, the additional power demand introduced by massive charging of PHEVs can potentially cause unacceptable voltage

  6. Development of Low-Voltage and Large Current DC Power Supply with High-Frequency Transformer Coupling

    E-Print Network [OSTI]

    Fujimoto, Hiroshi

    Development of Low-Voltage and Large Current DC Power Supply with High-Frequency Transformer excellent performance. Keywords DC power supply, low-voltage and large-current, high-frequency transformer Iobe (MACOHO Co., Ltd.) Abstract This paper describes low-voltage and large-current DC power supplies

  7. Real Power and Reactive Power Control of a Three-Phase Single-Stage-PV System and PV voltage Stability

    SciTech Connect (OSTI)

    Li, Huijuan [ORNL] [ORNL; Xu, Yan [ORNL] [ORNL; Adhikari, Sarina [ORNL] [ORNL; Rizy, D Tom [ORNL] [ORNL; Li, Fangxing [ORNL] [ORNL; Irminger, Philip [ORNL] [ORNL

    2012-01-01T23:59:59.000Z

    Grid-connected photovoltaic (PV) systems with power electronic interfaces can provide both real and reactive power to meet power system needs with appropriate control algorithms. This paper presents the control algorithm design for a three-phase single-stage grid-connected PV inverter to achieve either maximum power point tracking (MPPT) or a certain amount of real power injection, as well as the voltage/var control. The switching between MPPT control mode and a certain amount of real power control mode is automatic and seamless. Without the DC-to-DC booster stage, PV DC voltage stability is an important issue in the control design especially when the PV inverter is operating at maximum power point (MPP) with voltage/var control. The PV DC voltage collapse phenomenon and its reason are discussed. The method based on dynamic correction of the PV inverter output is proposed to ensure PV DC voltage stability. Simulation results of the single-stage PV system during system disturbances and fast solar irradiation changes confirm that the proposed control algorithm for single-stage PV inverters can provide appropriate real and reactive power services and ensure PV DC voltage stability during dynamic system operation and atmospheric conditions.

  8. Safe-commutation principle for direct single-phase AC-AC converters for use in audio power

    E-Print Network [OSTI]

    and G, expressed as very low total harmonic distortion + noise (THD+N) levels and supplemented. SIngle Conversion stage AMplifier (SICAM) is the next im- portant evolutionary step in designing-stage AC-AC audio power amplifiers. As compared with the bridge commutation with load current or source

  9. Standby Voltage Scaling for Reduced Power B. Calhoun, A. Chandrakasan

    E-Print Network [OSTI]

    Calhoun, Benton H.

    Engineering Massachusetts Institute of Technology, Cambridge, MA Abstract Lowering VDD during standby mode leakage, gate leakage, GIDL, and forward biased diode leak- age[2]. At the 0.13 m technology node to pinch in the rail voltages during standby[5]. The quantity and sizes of the devices used in the diode

  10. Power Management Unit A digitalized Embedded Linear Voltage Regulator for

    E-Print Network [OSTI]

    Wichmann, Felix

    Climate Control Cooling FAN Park Distance Control Adaptive Cruise Control Night Vision Blindspot Detection cost More expensive mask cost More sensitive to radiation Higher leakage current Lower voltage headroom) System CostsSystem Costs Si-Area, Test Time, Package (# of pins) Development Cost/ Time to market

  11. Power flow analysis for DC voltage droop controlled DC microgrids

    E-Print Network [OSTI]

    Chaudhary, Sanjay

    loss, such as photovoltaic panels, batteries, fuel cells, LEDs, and electronic loads, DC microgrids sharing and secondary voltage regulation can now be analytically studied, and specialized optimization of the DC microgrid, in term of systematic analysis, protection coordination design, network optimization

  12. The design of an A-C voltage regulator using a Wein Bridge detector

    E-Print Network [OSTI]

    Brown, Richard True

    1959-01-01T23:59:59.000Z

    ) the regulator would correct for changes in input voltage only, as the detector ie on the input side of the controller. In Figures 1(c) and 1(d) the xegulator would corxect fox' changes in input or load conditions as the detector is placed directly across... the load. Em D Figure 1; Four types of regulator connections. The connections shown in Figures 1(b) and l(d) are limited in that the output is usually less than the input voltage, whereas in Figures 1(a) and 1(c) the controller voltage can buck...

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

    SciTech Connect (OSTI)

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

    1994-11-01T23:59:59.000Z

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

  14. Power Deregulation: Eliminating Off-Chip Voltage Regulation Circuitry From Embedded Systems

    E-Print Network [OSTI]

    Joseph, Russ

    Power Deregulation: Eliminating Off-Chip Voltage Regulation Circuitry From Embedded Systems analytical techniques, power models, and detailed full-system simulation of numerous benchmarks from.northwestern.edu ABSTRACT In battery-powered embedded systems, dedicated circuitry is used to convert stored energy

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

    E-Print Network [OSTI]

    Catholic University of Chile (Universidad Católica de Chile)

    . of Electrical Engineering (2) Dept. of Electrical Engineering Universidad de Concepción Universidad Católica de and reactive power in power distribution systems [1], [2], [3]. Although many technical papers related power to compensate converter losses and to keep the dc voltages constant. Simulated results for steady

  16. AC Resonant charger with charge rate unrelated to primary power frequency

    DOE Patents [OSTI]

    Watson, Harold (Torrance, CA)

    1982-01-01T23:59:59.000Z

    An AC resonant charger for a capacitive load, such as a PFN, is provided with a variable repetition rate unrelated to the frequency of a multi-phase AC power source by using a control unit to select and couple the phase of the power source to the resonant charger in order to charge the capacitive load with a phase that is the next to begin a half cycle. For optimum range in repetition rate and increased charging voltage, the resonant charger includes a step-up transformer and full-wave rectifier. The next phase selected may then be of either polarity, but is always selected to be of a polarity opposite the polarity of the last phase selected so that the transformer core does not saturate. Thyristors are used to select and couple the correct phase just after its zero crossover in response to a sharp pulse generated by a zero-crossover detector. The thyristor that is turned on then automatically turns off after a full half cycle of its associated phase input. A full-wave rectifier couples the secondary winding of the transformer to the load so that the load capacitance is always charged with the same polarity.

  17. Lurching towards markets for power: China's electricity policy 19852007 Xiaoli Zhao a,c,

    E-Print Network [OSTI]

    Lyon, Thomas P.

    Institute for Low Carbon Economy and Trade, North China Electric Power University, Beijing, China a r t i cLurching towards markets for power: China's electricity policy 1985­2007 Xiaoli Zhao a,c, , Thomas P. Lyon b , Cui Song a,c a School of Economics and Management, North China Electric Power University

  18. Transmission Channel Model and Capacity of Overhead Multi-conductor Medium-Voltage Power-lines for Broadband Communications

    E-Print Network [OSTI]

    Kavehrad, Mohsen

    Transmission Channel Model and Capacity of Overhead Multi-conductor Medium-Voltage Power-lines signal transmission, power-line has many non-ideal properties as a communications medium. Impedance-voltage power distribution networks for broadband power-line communications applications. Keywords - channel

  19. Development of Low-Voltage and Large-Current DC Power Supply with High-Frequency Transformer Coupling

    E-Print Network [OSTI]

    Fujimoto, Hiroshi

    Development of Low-Voltage and Large-Current DC Power Supply with High-Frequency Transformer-voltage and large-current DC power supply with a high-frequency transformer coupling. The power supply is simply·,Zü"gg"X·C~R,êC"_N^"X Keywords: DC power supply, low-voltage and large-current, high-frequency transformer, leakage inductance 1

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

    E-Print Network [OSTI]

    Pota, Himanshu Roy

    Voltage Oscillations in Power Distribution Networks in the Presence of DFIGs and Induction Motor of oscillation between the electromechanical and subsynchronous oscillations of power systems. Time for the types of oscillations that occur in distribution systems. Finally, significant parameters of the system

  1. Voltage Stability and Frequency Synchronization of Weak Power Distribution Networks with Inverter-Based

    E-Print Network [OSTI]

    Lemmon, Michael

    a part of microgrids, are incorporated to improve power quality and reliability when disruptions happen of microgrids [13], together with oth- er generation, storage and load units. These microgrid- s are installedVoltage Stability and Frequency Synchronization of Weak Power Distribution Networks with Inverter

  2. Reactive power management of distribution networks with wind generation for improving voltage stability

    E-Print Network [OSTI]

    Pota, Himanshu Roy

    -loadability Reactive power margin Wind turbine a b s t r a c t This paper proposes static and dynamic VAR planningReactive power management of distribution networks with wind generation for improving voltage February 2013 Available online Keywords: Composite load Distributed generation D-STATCOM Q

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

    E-Print Network [OSTI]

    Liberzon, Daniel

    violations and shapes the voltage profile in radial distribution networks, even in the presence the Equinox house [7] are examples of residential PV installations capable of producing an amount of power significantly larger than its average load during peak hours of the day. Similarly, the additional power demand

  4. Power System Stability Using Decentralized Under Frequency and Voltage Load Shedding

    E-Print Network [OSTI]

    Silva, Filipe Faria Da

    not be adaptive to disturbance scale. Besides, due to equality of the frequency throughout the entire power system of Frequency (ROCOF). In order to localize the LS scheme close to the disturbance place, this scheme utilizesPower System Stability Using Decentralized Under Frequency and Voltage Load Shedding Bakhtyar

  5. High Power, High Voltage FETs in Linear Applications: A User's Perspective

    SciTech Connect (OSTI)

    N. Greenough, E. Fredd, S. DePasquale

    2009-09-21T23:59:59.000Z

    The specifications of the current crop of highpower, high-voltage field-effect transistors (FETs) can lure a designer into employing them in high-voltage DC equipment. Devices with extremely low on-resistance and very high power ratings are available from several manufacturers. However, our experience shows that high-voltage, linear operation of these devices at near-continuous duty can present difficult reliability challenges at stress levels well-below their published specifications. This paper chronicles the design evolution of a 600 volt, 8 ampere shunt regulator for use with megawatt-class radio transmitters, and presents a final design that has met its reliability criteria.

  6. Voltage Collapse and ODE Approach to Power Flows: Analysis of a Feeder Line with Static Disorder in Consumption/Production

    E-Print Network [OSTI]

    Chertkov, M; Turtisyn, K; Chernyak, V; Lebedev, V

    2011-01-01T23:59:59.000Z

    We consider a model of a distribution feeder connecting multiple loads to the sub-station. Voltage is controlled directly at the head of the line (sub-station), however, voltage anywhere further down the line is subject to fluctuations, caused by irregularities of real and reactive distributed power consumption/generation. The lack of a direct control of voltage along the line may result in the voltage instability, also called voltage collapse - phenomenon well known and documented in the power engineering literature. Motivated by emerging photo-voltaic technology, which brings a new source of renewable generation but also contributes significant increase in power flow fluctuations, we reexamine the phenomenon of voltage stability and collapse. In the limit where the number of consumers is large and spatial variations in power flows are smooth functions of position along the feeder, we derive a set of the power flow Ordinary Differential Equations (ODE), verify phenomenon of voltage collapse, and study the ef...

  7. A combined compensation method for the output voltage of an insulated core transformer power supply

    SciTech Connect (OSTI)

    Yang, L.; Yang, J., E-mail: jyang@mail.hust.edu.cn; Liu, K. F.; Qin, B.; Chen, D. Z. [State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2014-06-15T23:59:59.000Z

    An insulated core transformer (ICT) power supply is an ideal high-voltage generator for irradiation accelerators with energy lower than 3 MeV. However, there is a significant problem that the structure of the segmented cores leads to an increase in the leakage flux and voltage differences between rectifier disks. A high level of consistency in the output of the disks helps to achieve a compact structure by improving the utilization of both the rectifier components and the insulation distances, and consequently increase the output voltage of the power supply. The output voltages of the disks which are far away from the primary coils need to be improved to reduce their inhomogeneity. In this study, by investigating and comparing the existing compensation methods, a new combined compensation method is proposed, which increases the turns on the secondary coils and employs parallel capacitors to improve the consistency of the disks, while covering the entire operating range of the power supply. This method turns out to be both feasible and effective during the development of an ICT power supply. The non-uniformity of the output voltages of the disks is less than 3.5% from no-load to full-load, and the power supply reaches an output specification of 350 kV/60 mA.

  8. Miniaturized, low-voltage power converters with fast dynamic response

    E-Print Network [OSTI]

    Giuliano, David (David Michael)

    2013-01-01T23:59:59.000Z

    This thesis introduces a two-stage architecture that combines the strengths of switched capacitor (SC) techniques (small size, light-load performance) with the high efficiency and regulation capability of switch-mode power ...

  9. Realizing Low Power FPGAs: A Design Partitioning Algorithm for Voltage Scaling and A Comparative Evaluation of Voltage Scaling Techniques for FPGAs

    E-Print Network [OSTI]

    Kuzmanovic, Aleksandar

    switchboxes, FPGAs are less energy efficient than ASICs [1]. An experimental study comparing the energy reliability due to excessive heat generation (due to high power) is a concern, power improvement in FPGAs that dual-Vdd achieves more power reduction than by Vdd scaling (i.e. adjusting the supply voltage level

  10. Voltage multi-stability in distribution grids with power flow reversal

    E-Print Network [OSTI]

    Hung D. Nguyen; Konstantin Turitsyn

    2014-07-08T23:59:59.000Z

    High levels of penetration of distributed generation and aggressive reactive power compensation with modern power electronics may result in the reversal of active and reactive power flows in future distribution grids. The voltage stability of these operating conditions may be very different from the more traditional power consumption regime. We study the stability characteristics of distribution networks with reversed power flow. After introducing a universal algebraic approach to characterize all the solutions of the power flow equations, we show that new solutions appear in the reversed power flow regime even in the simplest three bus systems. We show that the some of these solutions are stable and the system may exhibit a phenomenon of multistability, where multiple stable equilibria co-exist at the given set of parameters, and the system may converge to an undesirable equilibrium after a disturbance. These predictions are validated with dynamic simulations of two different systems. Under certain conditions the new states are viable and may be characterized by relatively high voltages. Possible approaches towards reactive power/voltage regulation as well as permissible distributed generation capacity in future power systems are proposed and discussed in the end of the paper.

  11. Using Dielectric Losses to De-Ice Power Transmission Lines with 100 kHz High-Voltage

    E-Print Network [OSTI]

    Using Dielectric Losses to De-Ice Power Transmission Lines with 100 kHz High-Voltage Excitation J DIELECTRIC LOSSES TO DE-ICE POWER TRANSMISSION LINES . . . 1 Using Dielectric Losses to De-Ice Power Transmission Lines with 100 kHz High-Voltage Excitation Joshua D. McCurdy, Charles R. Sullivan and Victor F

  12. Ver.2003.01.27 Development of Low-Voltage and Large-Current DC Power Supply

    E-Print Network [OSTI]

    Fujimoto, Hiroshi

    describes low-voltage and large-current DC power supplies with a high-frequency transformer coupling. Two Ver.2003.01.27 Development of Low-Voltage and Large-Current DC Power Supply-bridge inverter, an amorphous-core step down transformer and a schottky diode rectifier. One power supply operates

  13. Direct current uninterruptible power supply method and system

    DOE Patents [OSTI]

    Sinha, Gautam

    2003-12-02T23:59:59.000Z

    A method and system are described for providing a direct current (DC) uninterruptible power supply with the method including, for example: continuously supplying fuel to a turbine; converting mechanical power from the turbine into alternating current (AC) electrical power; converting the AC electrical power to DC power within a predetermined voltage level range; supplying the DC power to a load; and maintaining a DC load voltage within the predetermined voltage level range by adjusting the amount of fuel supplied to the turbine.

  14. Modeling and Verification of Distributed Generation and Voltage Regulation Equipment for Unbalanced Distribution Power Systems; Annual Subcontract Report, June 2007

    SciTech Connect (OSTI)

    Davis, M. W.; Broadwater, R.; Hambrick, J.

    2007-07-01T23:59:59.000Z

    This report summarizes the development of models for distributed generation and distribution circuit voltage regulation equipment for unbalanced power systems and their verification through actual field measurements.

  15. Soft-Switching High-Frequency AC-Link Universal Power Converters with Galvanic Isolation 

    E-Print Network [OSTI]

    Amirabadi, Mahshid

    2013-08-07T23:59:59.000Z

    be used in a variety of applications, including photovoltaic power generation, wind power generation, and electric vehicles. In these converters the link current and voltage are both alternating and their frequency can be high, which leads...

  16. Voltage and Frequency Stability of Weak Power Distribution Networks with Droop-Controlled

    E-Print Network [OSTI]

    Lemmon, Michael

    Voltage and Frequency Stability of Weak Power Distribution Networks with Droop analysis, because of coupled network dynamics. Additionally, droop controlled rotational and electronic DG distribution network coupled with droop-controlled DG's, which are based on both fast inverters and SG

  17. Method for reducing fuel cell output voltage to permit low power operation

    DOE Patents [OSTI]

    Reiser, Carl A. (Glastonbury, CT); Landau, Michael B. (West Hartford, CT)

    1980-01-01T23:59:59.000Z

    Fuel cell performance is degraded by recycling a portion of the cathode exhaust through the cells and, if necessary, also reducing the total air flow to the cells for the purpose of permitting operation below a power level which would otherwise result in excessive voltage.

  18. Impacts of Large-Scale Wind Generators Penetration on the Voltage Stability of Power Systems

    E-Print Network [OSTI]

    Pota, Himanshu Roy

    development of wind energy tech- nology and the current world-wide status of grid-connected as well as standImpacts of Large-Scale Wind Generators Penetration on the Voltage Stability of Power Systems M. J systems and their dynamic behaviours to identify critical issues that limit the large-scale integration

  19. Effects of applied voltages and dissolved oxygen on sustained power generation by microbial fuel cells

    E-Print Network [OSTI]

    Effects of applied voltages and dissolved oxygen on sustained power generation by microbial fuel), Faculty of Advanced Technology, University of Glamorgan, Pontypridd RCT CF37 1DL, UK Oxygen intrusion chamber MFCs at the end of a cycle when the substrate is depleted. A slight increase in dissolved oxygen

  20. Transient power supply voltage (v{sub DDT}) analysis for detecting IC defects

    SciTech Connect (OSTI)

    Cole, E.I. Jr.; Soden, J.M.; Beegle, R.W. [and others

    1997-04-01T23:59:59.000Z

    Transient power supply voltage (V{sub DDT}) analysis is a new testing technique demonstrated as a powerful alternative and complement to I{sub DDQ} testing. V{sub DDT} takes advantage of the limited response time of a voltage supply to the changing power demands of an IC during operation. Changes in the V{sub DD} response time are used to detect increases in power demand with resolutions of 100 nA at 100 kHz, 1 {mu}A at 1 MHz, and 2.5 {mu}A at 1.5 MHz. These current sensitivities have been shown for ICs with quiescent currents < 0.1 {mu}A and > 300 {mu}A. The V{sub DDT} signal acquisition protocols, frequency versus sensitivity tradeoffs, hardware considerations and limitations, data examples, and areas for future research are described.

  1. Approaches to building single-stage AC/AC conversion switch-mode audio power Petar Ljusev and Michael A.E. Andersen

    E-Print Network [OSTI]

    power amplifiers with a separate power supply, it is expected that direct conversion will provide better performance. It is also quite appealing for the Active Trans- ducer (AT) [2] approach for direct conversionApproaches to building single-stage AC/AC conversion switch-mode audio power amplifiers Petar

  2. Page 1 of 9 SCT Bias Voltage Power Supply Specification -Version V2.04 February 2001

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    Page 1 of 9 SCT Bias Voltage Power Supply Specification - Version V2.04 February 2001 Project&LV special crate, crate controller, CANbus interface to DCS E.Górnicki, S.Koperny, P.Malecki February 2001 #12;Page 2 of 9 SCT Bias Voltage Power Supply Specification - Version V2.04 February 2001 1. Scope

  3. IEEE TRANSACTIONS ON POWER SYSTEMS, VOL. 15, NO. 3, AUGUST 2000 1137 A Fast Voltage Security Assessment

    E-Print Network [OSTI]

    Venkatasubramanian, Mani V.

    IEEE TRANSACTIONS ON POWER SYSTEMS, VOL. 15, NO. 3, AUGUST 2000 1137 A Fast Voltage Security--This paper presents a fast method for use in on-line voltage security assessment. The objective here from Static Security Analysis (SSA). Index Terms--Adaptive bounding, electrical distance, power flow

  4. A Capacitor-Less Wide-Band Power Supply Rejection Low Drop-Out Voltage Regulator with Capacitance Multiplier

    E-Print Network [OSTI]

    Wang, Mengde

    2014-05-22T23:59:59.000Z

    A Low Drop-Out (LDO) voltage regulator with both capacitor-less and high power supply rejection (PSR) bandwidth attributes is highly admired for an integrated power management system of mobile electronics. The capacitor-less feature is demanded...

  5. A Comparison of the AC and DC Power Flow Models for LMP Calculations

    E-Print Network [OSTI]

    A Comparison of the AC and DC Power Flow Models for LMP Calculations Thomas J. Overbye, Xu Cheng power flow model for LMP-based market calculations. The paper first provides a general discussion of balanced, three phase, electric power transmission networks is through the solution of the power flow. From

  6. The Hybrid Power Flow Controller A New Concept for Flexible AC Transmission

    E-Print Network [OSTI]

    Lehn, Peter W.

    large and costly projects. Over the years, environmental, right­of­way, and cost prob- lems have delayedThe Hybrid Power Flow Controller A New Concept for Flexible AC Transmission Jovan Z. Bebic Electric flow controller topologies are proposed for flexible AC transmission systems (FACTS). The first one

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

    SciTech Connect (OSTI)

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

    2014-09-30T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Fallier, William F. (William Frederick)

    2007-01-01T23:59:59.000Z

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

  9. Low Voltage, Low Power Organic Light Emitting Transistors for AMOLED Displays

    SciTech Connect (OSTI)

    McCarthy, M. A. [University of Florida, Gainesville; Liu, B. [University of Florida, Gainesville; Donoghue, E. P. [University of Florida, Gainesville; Kravchenko, Ivan I [ORNL; Kim, D. Y. [University of Florida, Gainesville; Reynolds, J. R. [University of Florida, Gainesville; So, Franky [University of Florida, Gainesville; Rinzler, A. G. [University of Florida, Gainesville

    2011-01-01T23:59:59.000Z

    Low voltage, low power dissipation, high aperture ratio organic light emitting transistors are demonstrated. The high level of performance is enabled by a carbon nanotube source electrode that permits integration of the drive transistor and the organic light emitting diode into an efficient single stacked device. Given the demonstrated performance, this technology could break the technical logjam holding back widespread deployment of active matrix organic light emitting displays at flat panel screen sizes.

  10. Investigation of CandidateTechniquesfor High-Frequency AC Distributed Power Systems'

    E-Print Network [OSTI]

    Wu, Shin-Tson

    Investigation of CandidateTechniquesfor High-Frequency AC Distributed Power Systems' Shiguo Luo power systems PPSs) have been used extensively and a considerable amount of information is availableon and outlined in this paper. I. INTRODUCTION Power conversion system design issues are becoming increasingly

  11. A nonlinear robust HVDC control for a parallel AC/DC power system

    E-Print Network [OSTI]

    Qu, Zhihua

    A nonlinear robust HVDC control for a parallel AC/DC power system Hongzhi Cai a , Zhihua Qu b. Keywords: Robust control; HVDC; Power system; Stability; Lyapunov method 1. Introduction It has been recognized that, through an HVDC transmission line, fast electronic control can be applied on the DC power

  12. IEEE TRANSACTIONS ON POWER SYSTEMS, VOL. XX, NO. Y, MONTH 2001 1 Global Transient Stability and Voltage Regulation

    E-Print Network [OSTI]

    Guo, Yi

    and voltage regulator. The designed controller is smooth and robust with respect to di#11;erent transient and voltage regulation are both important properties of power system control, but they are ascribed to di#11 of system behavior. We design in this paper a global controller to co-ordinate the transient stabilizer

  13. Impact of Wind Power Plants on Voltage and Transient Stability of Power Systems

    SciTech Connect (OSTI)

    Muljadi, E.; Nguyen, Tony B.; Pai, M. A.

    2008-09-30T23:59:59.000Z

    A standard three-machine, nine-bus wind power system is studied and augmented by a radially connected wind power plant that contains 22 wind turbine generators.

  14. Utility-Scale Power Router: Dynamic Control of Grid Assets Using Direct AC Converter Cells

    SciTech Connect (OSTI)

    None

    2010-09-01T23:59:59.000Z

    ADEPT Project: Georgia Tech is developing a cost-effective, utility-scale power router that uses an enhanced transformer to more efficiently direct power on the grid. Existing power routing technologies are too expensive for widespread use, but the ability to route grid power to match real-time demand and power outages would significantly reduce energy costs for utilities, municipalities, and consumers. Georgia Tech is adding a power converter to an existing grid transformer to better control power flows at about 1/10th the cost of existing power routing solutions. Transformers convert the high-voltage electricity that is transmitted through the grid into the low-voltage electricity that is used by homes and businesses. The added converter uses fewer steps to convert some types of power and eliminates unnecessary power storage, among other improvements. The enhanced transformer is more efficient, and it would still work even if the converter fails, ensuring grid reliability.

  15. Soft-Switching High-Frequency AC-Link Universal Power Converters with Galvanic Isolation

    E-Print Network [OSTI]

    Amirabadi, Mahshid

    2013-08-07T23:59:59.000Z

    ) direct drive using wound-field synchronous generator [10]. ...................................................................................................... 6 Figure 6 Dc-dc buck-boost converter: (a) configuration, (b) energizing mode (mode 1), (c...) de-energizing mode (mode 2), (d) voltage and current waveforms ........ 12 Figure 7 An alternative representation of the dc-dc buck-boost converter ...................... 13 Figure 8 Dc-dc ac-link buck-boost converter: configuration, behavior...

  16. The EP-4(0) shielding kits: a new approach to protection from induced voltage

    SciTech Connect (OSTI)

    Vorob'ev, A. Yu.; Otmorskii, S. G.; Smekalov, V. V.; Gorozhankina, E. N.; Sosunov, N. N.; Bol'shunov, A. M.

    2011-09-15T23:59:59.000Z

    Problems of safety in work on overhead power lines and the overhead railroad ac contact network under induced voltages are considered. The use of additional individual protection systems is proposed to provide protection from electric shock during such work.

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

    SciTech Connect (OSTI)

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

    2008-01-01T23:59:59.000Z

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

  18. High voltage ignition of high pressure microwave powered UV light sources

    SciTech Connect (OSTI)

    Frank, J.D.; Cekic, M.; Wood, C.H. [Fusion U.V. Curing Systems Corp., Gaithersburg, MD (United States)

    1997-12-31T23:59:59.000Z

    Industrial microwave powered (electrodeless) light sources have been limited to quiescent pressures of {approximately}300 Torr of buffer gas and metal-halide fills. The predominant reason for such restrictions has been the inability to microwave ignite the plasma due to the collisionality of higher pressure fills and/or the electronegativity of halide bulb chemistries. Commercially interesting bulb fills require electric fields for ionization that are often large multiples of the breakdown voltage for air. Many auxiliary ignition methods are evaluated for efficiency and practicality before the choice of a high-voltage system with a retractable external electrode. The scheme utilizes a high voltage pulse power supply and a novel field emission source. Acting together they create localized condition of pressure reduction and high free electron density. This allows the normal microwave fields to drive this small region into avalanche, ignite the bulb, and heat the plasma to its operating point (T{sub e} {approx} 0.5 eV). This process is currently being used in a new generation of lamps, which are using multi-atmospheric excimer laser chemistries and pressure and constituent enhanced metal-halide systems. At the present time, production prototypes produce over 900 W of radiation in a 30 nm band, centered at 308 nm. Similarly, these prototypes when loaded with metal-halide bulb fills produce over 1 kW of radiation in 30 nm wide bands, centered about the wavelength of interest.

  19. ac power loss: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    are used in many power aplicatons like power cables, high power electric motors, transformers or fault limiters. HTS Motors HTS motors use HTS windings instead of conventional...

  20. High voltage-high power components for large space power distribution systems

    SciTech Connect (OSTI)

    Renz, D.D.

    1984-08-01T23:59:59.000Z

    For over a decade, Lewis Research Center has been developing space power components. These components include a family of bi-polar power switching transistors, fast switching power diodes, heat pipe cooled high-frequency transformers and inductors, high frequency conduction cooled transformers, high powerhigh frequency capacitors, remote power controllers and rotary power transfer devices. Many of these components such as the power switching transistors, power diodes and the high frequency capacitor are commercially available. All the other components have been developed to the prototype level. Series resonant dc/dc converters have been built to the 25 kW level.

  1. Design, construction and operational results of the IGBT controlled solid state modulator high voltage power supply used in the high power RF systems of the Low Energy Demonstration Accelerator of the accelerator production of tritium (APT) project

    SciTech Connect (OSTI)

    Bradley, J.T. III; Rees, D.; Przeklasa, R.S. [Los Alamos National Lab., NM (United States); Scott, M.C. [Continental Electronics Corp., Dallas, TX (United States)

    1998-12-31T23:59:59.000Z

    The 1700 MeV, 100 mA Accelerator Production of Tritium (APT) Proton Linac will require 244 1 MW, continuous wave RF systems. 1 MW continuous wave klystrons are used as the RF source and each klystron requires 95 kV, 17 A of beam voltage and current. The cost of the DC power supplies is the single largest percentage of the total RF system cost. Power supply reliability is crucial to overall RF system availability and AC to DC conversion efficiency affects the operating cost. The Low Energy Demonstration Accelerator (LEDA) being constructed at Los Alamos National Laboratory (LANL) will serve as the prototype and test bed for APT. The design of the RF systems used in LEDA is driven by the need to field test high efficiency systems with extremely high reliability before APT is built. The authors present a detailed description and test results of one type of advanced high voltage power supply system using Insulated Gate Bipolar Transistors (IGBTs) that has been used with the LEDA High Power RF systems. The authors also present some of the distinctive features offered by this power supply topology, including crowbarless tube protection and modular construction which allows graceful degradation of power supply operation.

  2. A high voltage pulsed power supply for capillary discharge waveguide applications

    SciTech Connect (OSTI)

    Abuazoum, S.; Wiggins, S. M.; Issac, R. C.; Welsh, G. H.; Vieux, G.; Jaroszynski, D. A. [Department of Physics, Scottish Universities Physics Alliance, University of Strathclyde, Glasgow G4 0NG (United Kingdom); Ganciu, M. [Low Temperature Plasma Department, National Institute of Lasers, Plasma and Radiation Physics, 077125, Magurele, Bucharest (Romania)

    2011-06-15T23:59:59.000Z

    We present an all solid-state, high voltage pulsed power supply for inducing stable plasma formation (density {approx}10{sup 18} cm{sup -3}) in gas-filled capillary discharge waveguides. The pulser (pulse duration of 1 {mu}s) is based on transistor switching and wound transmission line transformer technology. For a capillary of length 40 mm and diameter 265 {mu}m and gas backing pressure of 100 mbar, a fast voltage pulse risetime of 95 ns initiates breakdown at 13 kV along the capillary. A peak current of {approx}280 A indicates near complete ionization, and the r.m.s. temporal jitter in the current pulse is only 4 ns. Temporally stable plasma formation is crucial for deploying capillary waveguides as plasma channels in laser-plasma interaction experiments, such as the laser wakefield accelerator.

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

    E-Print Network [OSTI]

    Assaad, Rida Shawky

    2011-02-22T23:59:59.000Z

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

  4. BogdanovTakens bifurcation points and Sil'nikov homoclinicity in a simple power system model of voltage

    E-Print Network [OSTI]

    Bath, University of

    Bogdanov­Takens bifurcation points and Ÿ Sil'nikov homoclinicity in a simple power system model of a simple power system model is investigated, with respect to changes to both the real and reative loads: Voltage Collapse, power system, Takens­Bogdanov, Bogdanov­Takens, Bifurcation, Monte­Carlo, Basin

  5. 1504 IEEE JOURNAL OF SOLID-STATE CIRCUITS, VOL. 39, NO. 9, SEPTEMBER 2004 Standby Power Reduction Using Dynamic Voltage

    E-Print Network [OSTI]

    Calhoun, Benton H.

    1504 IEEE JOURNAL OF SOLID-STATE CIRCUITS, VOL. 39, NO. 9, SEPTEMBER 2004 Standby Power Reduction. Chandrakasan, Fellow, IEEE Abstract--Lowering during standby mode reduces power by decreasing both voltage where state is lost gives the best power savings. We show that "canary" flip-flops provide a mechanism

  6. Abstract--This paper reports a method to evaluate composite power system reliability indices incorporating the voltage

    E-Print Network [OSTI]

    3 Abstract--This paper reports a method to evaluate composite power system reliability indices power flow (OPF) computation algorithm, considering the steady state voltage stability margin constraint In the deregulated power systems, reliability evaluation encompassing the system security features has come

  7. Halbach array generator/motor having an automatically regulated output voltage and mechanical power output

    DOE Patents [OSTI]

    Post, Richard F.

    2005-02-22T23:59:59.000Z

    A motor/generator having its stationary portion, i.e., the stator, positioned concentrically within its rotatable element, i.e., the rotor, along its axis of rotation. The rotor includes a Halbach array. The stator windings are switched or commutated to provide a DC motor/generator much the same as in a conventional DC motor/generator. The voltage and power are automatically regulated by using centrifugal force to change the diameter of the rotor, and thereby vary the radial gap in between the stator and the rotating Halbach array, as a function of the angular velocity of the rotor.

  8. ac power flow: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    are observed. 2. The package thermal impedance Kretchmar, R. Matthew 266 Nuclear Power Plant Design Project Fission and Nuclear Technologies Websites Summary: Nuclear Power Plant...

  9. ac power source: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and Information Sciences Websites Summary: source. Al- ternative power sources such as fuel cells (FCs) have substantially different power-time systems and embedded systems...

  10. ac power distribution: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ON POWER SYSTEMS, VOL. 29, NO. 1, JANUARY 2014 203 Distribution Locational Marginal Pricing for Optimal Power Transmission, Distribution and Plants Websites Summary:...

  11. A Partitioning Approach for Parallel Simulation of AC-Radial Shipboard Power Systems

    E-Print Network [OSTI]

    Uriarte, Fabian Marcel

    2011-08-08T23:59:59.000Z

    ................................................................................ 62 Fig. 2.4.15. Under-voltage relay logic for low voltage protective devices (LVXs) ......... 63 Fig. 2.4.16. Over-current relay and low-voltage protective device model ....................... 64 Fig. 2.4.17. Over-current relay and low... automatic- or manual bus transfers (ABTs and MBTs, or XBTs to refer to either). The major types of protective devices utilized in the U.S. Navy ship electrical power systems are fuses, circuit breakers, and relays [10]. The purpose of protective...

  12. High voltage power supply. (Latest citations from the US Patent bibliographic file with exemplary claims). Published Search

    SciTech Connect (OSTI)

    NONE

    1996-03-01T23:59:59.000Z

    The bibliography contains citations of selected patents concerning high voltage power supply systems and devices. References describe direct and high current power supplies, microprocessor controlled and programmable systems, amplifiers, power supply stabilization, power circuit protection, feedback control, and pulse modulation. Applications cover laser systems, x-ray tubes, electrophoresis, video apparatus, radar and electronic warfare systems, helmet mounted display, and electrosurgery. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  13. High voltage power supply. (Latest citations from the US Patent bibliographic file with exemplary claims). Published Search

    SciTech Connect (OSTI)

    NONE

    1997-06-01T23:59:59.000Z

    The bibliography contains citations of selected patents concerning high voltage power supply systems and devices. References describe direct and high current power supplies, microprocessor controlled and programmable systems, amplifiers, power supply stabilization, power circuit protection, feedback control, and pulse modulation. Applications cover laser systems, x-ray tubes, electrophoresis, video apparatus, radar and electronic warfare systems, helmet mounted display, and electrosurgery. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  14. AC system stability analysis and assessment for Shipboard Power Systems 

    E-Print Network [OSTI]

    Qi, Li

    2006-04-12T23:59:59.000Z

    The electric power systems in U.S. Navy ships supply energy to sophisticated systems for weapons, communications, navigation and operation. The reliability and survivability of a Shipboard Power System (SPS) are critical ...

  15. ac input power: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    architecture was ... Salazar, Nathaniel Jay Tobias 2012-01-01 8 On the power of real Turing machines over binary inputs Mathematics Websites Summary: On the power of real Turing...

  16. AC system stability analysis and assessment for Shipboard Power Systems

    E-Print Network [OSTI]

    Qi, Li

    2006-04-12T23:59:59.000Z

    The electric power systems in U.S. Navy ships supply energy to sophisticated systems for weapons, communications, navigation and operation. The reliability and survivability of a Shipboard Power System (SPS) are critical to the mission of a Navy...

  17. POWER ELECTRONICS HARMONIC ANALYSIS BASED ON THE LINEAR TIME PERIODIC MODELING. APPLICATIONS FOR AC/DC/AC POWER

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    /Simulink simulations. Key words: power system harmonics, power electronic, linear time periodic modeling, PWM, control1 POWER ELECTRONICS HARMONIC ANALYSIS BASED ON THE LINEAR TIME PERIODIC MODELING. APPLICATIONS in power electronic systems. The considered system is described by a set of differential equations, which

  18. IEEE TRANSACTIONS ON POWER SYSTEMS, VOL. 7, NO. 2, MAY 1992, PP. 673 683. POINT OF COLLAPSE METHODS APPLIED TO AC DC POWER SYSTEMS

    E-Print Network [OSTI]

    Cañizares, Claudio A.

    -node bifurcations in power systems including high voltage direct current HVDC transmission. Bus voltage pro les, become plausible when the dynamics for the HVDC system are included. Keywords: Voltage collapse, HVDC the subject of increasing study over the past few years 1 . Furthermore, the relative wide spread use of HVDC

  19. ac power lines: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    A FUNDAMENTAL characteristic construction of both generation facilities and new transmission lines, so better utilization of existing power Lehn, Peter W. 5 A new high performance...

  20. Microprocessor-based random PWM schemes for DC-AC power conversion

    SciTech Connect (OSTI)

    Hui, S.Y.R. [Univ. of Sydney, New South Wales (Australia). Dept. of Electrical Engineering] [Univ. of Sydney, New South Wales (Australia). Dept. of Electrical Engineering; [City Univ. of Hong Kong, Kowloon (Hong Kong). Dept. of Electronic Engineering; Oppermann, I.; Sathiakumar, S. [Univ. of Sydney, New South Wales (Australia). Dept. of Electrical Engineering] [Univ. of Sydney, New South Wales (Australia). Dept. of Electrical Engineering

    1997-03-01T23:59:59.000Z

    Two classes of microprocessor-based random PWM (RPWM) real-time schemes for dc-ac power conversion are compared and evaluated. Performance of the RPWM schemes based on the mathematical and logical approaches is examined. The proposed schemes exhibit excellent harmonic content with all low and high-order harmonics suppressed and are suitable for both MOSFET and IGBT inverters.

  1. Atmospheric pressure plasma jet with high-voltage power supply based on piezoelectric transformer

    SciTech Connect (OSTI)

    Babij, Micha?; Kowalski, Zbigniew W., E-mail: zbigniew.w.kowalski@pwr.wroc.pl; Nitsch, Karol; Gotszalk, Teodor [Wroc?aw University of Technology, Wybrze?e Wyspia?skiego 27, 50-370 Wroc?aw (Poland)] [Wroc?aw University of Technology, Wybrze?e Wyspia?skiego 27, 50-370 Wroc?aw (Poland); Silberring, Jerzy [AGH University of Science and Technology, Al. A. Mickiewicza 30, 30-059 Kraków (Poland)] [AGH University of Science and Technology, Al. A. Mickiewicza 30, 30-059 Kraków (Poland)

    2014-05-15T23:59:59.000Z

    The dielectric barrier discharge plasma jet, an example of the nonthermal atmospheric pressure plasma jet (APPJ), generates low-temperature plasmas that are suitable for the atomization of volatile species and can also be served as an ionization source for ambient mass and ion mobility spectrometry. A new design of APPJ for mass spectrometry has been built in our group. In these plasma sources magnetic transformers (MTs) and inductors are typically used in power supplies but they present several drawbacks that are even more evident when dealing with high-voltage normally used in APPJs. To overcome these disadvantages, high frequency generators with the absence of MT are proposed in the literature. However, in the case of miniaturized APPJs these conventional power converters, built of ferromagnetic cores and inductors or by means of LC resonant tank circuits, are not so useful as piezoelectric transformer (PT) based power converters due to bulky components and small efficiency. We made and examined a novel atmospheric pressure plasma jet with PT supplier served as ionization source for ambient mass spectrometry, and especially mobile spectrometry where miniaturization, integration of components, and clean plasma are required. The objective of this paper is to describe the concept, design, and implementation of this miniaturized piezoelectric transformer-based atmospheric pressure plasma jet.

  2. Direct-conversion switching-mode audio power amplifier with active capacitive voltage clamp Petar Ljusev, Michael A.E. Andersen

    E-Print Network [OSTI]

    Direct-conversion switching-mode audio power amplifier with active capacitive voltage clamp Petar discusses the advantages and problems when implementing direct energy conversion switching-mode audio power on a direct-conversion switching-mode audio power ampli- fier with active capacitive voltage clamp

  3. Accepted for publication at IEEE Trans. Power Systems, July 2000, paper No. PE-006PRS (08-2000). Time Dependence of Controls to Avoid Voltage Collapse

    E-Print Network [OSTI]

    Cańizares, Claudio A.

    system model. Keywords: Power system control, voltage stability, voltage collapse, reactive power1 Accepted for publication at IEEE Trans. Power Systems, July 2000, paper No. PE-006PRS (08 is first presented with the help of a simple test system. The time dependence of the control actions

  4. Voltage balanced multilevel voltage source converter system

    DOE Patents [OSTI]

    Peng, F.Z.; Lai, J.S.

    1997-07-01T23:59:59.000Z

    Disclosed is a voltage balanced multilevel converter for high power AC applications such as adjustable speed motor drives and back-to-back DC intertie of adjacent power systems. This converter provides a multilevel rectifier, a multilevel inverter, and a DC link between the rectifier and the inverter allowing voltage balancing between each of the voltage levels within the multilevel converter. The rectifier is equipped with at least one phase leg and a source input node for each of the phases. The rectifier is further equipped with a plurality of rectifier DC output nodes. The inverter is equipped with at least one phase leg and a load output node for each of the phases. The inverter is further equipped with a plurality of inverter DC input nodes. The DC link is equipped with a plurality of rectifier charging means and a plurality of inverter discharging means. The plurality of rectifier charging means are connected in series with one of the rectifier charging means disposed between and connected in an operable relationship with each adjacent pair of rectifier DC output nodes. The plurality of inverter discharging means are connected in series with one of the inverter discharging means disposed between and connected in an operable relationship with each adjacent pair of inverter DC input nodes. Each of said rectifier DC output nodes are individually electrically connected to the respective inverter DC input nodes. By this means, each of the rectifier DC output nodes and each of the inverter DC input nodes are voltage balanced by the respective charging and discharging of the rectifier charging means and the inverter discharging means. 15 figs.

  5. ac power systems: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    the IEA R&D Wind's Topical expert meeting on Material recycling and life cycle analysis (LCA) of wind turbines 428 On the problem of reliable stabilization for large power systems...

  6. Designing AC Power Grids using Integer Linear Programming

    E-Print Network [OSTI]

    2011-02-18T23:59:59.000Z

    view of recent developments in integer linear programming, we revisit a less known .... optimal solution of the DC model was the minimum cost circuit of the network. ... Andersson, G.: Modelling and Analysis of Electric Power Systems (

  7. A power regulator for the generators on the A.C. network calculator

    E-Print Network [OSTI]

    Francis, Lawrence Gregg

    1956-01-01T23:59:59.000Z

    Regulator 6. The Thermocouple Transducer 7. The Detector Testing Layout 8, The Thermocvuplc Detector 9? Effect of. Varying Paver when feeintaining Vacs 12 15 17 and Voltage Constant 1Q. D. C. Thermocouple Voltage Vs, Generator Pover Output 19 11... is that the sucrsstion of generator outputs equals or exceeds the load on the system. power may be shifted from one generator to the other according to the condition under study. Thus, by loading sll but one unit to the desired levels and letting the other unit seek...

  8. Methods, systems and apparatus for controlling operation of two alternating current (AC) machines

    DOE Patents [OSTI]

    Gallegos-Lopez, Gabriel (Torrance, CA); Nagashima, James M. (Cerritos, CA); Perisic, Milun (Torrance, CA); Hiti, Silva (Redondo Beach, CA)

    2012-02-14T23:59:59.000Z

    A system is provided for controlling two AC machines. The system comprises a DC input voltage source that provides a DC input voltage, a voltage boost command control module (VBCCM), a five-phase PWM inverter module coupled to the two AC machines, and a boost converter coupled to the inverter module and the DC input voltage source. The boost converter is designed to supply a new DC input voltage to the inverter module having a value that is greater than or equal to a value of the DC input voltage. The VBCCM generates a boost command signal (BCS) based on modulation indexes from the two AC machines. The BCS controls the boost converter such that the boost converter generates the new DC input voltage in response to the BCS. When the two AC machines require additional voltage that exceeds the DC input voltage required to meet a combined target mechanical power required by the two AC machines, the BCS controls the boost converter to drive the new DC input voltage generated by the boost converter to a value greater than the DC input voltage.

  9. HYBRID CONTROL OF DISTRIBUTED GENERATORS CONNECTED TO WEAK RURAL NETWORKS TO MITIGATE VOLTAGE VARIATION

    E-Print Network [OSTI]

    Harrison, Gareth

    thermal power plants will increase the total and proportion of capacity of Distributed Generation (DG@iee.org; Robin.Wallace@ed.ac.uk ABSTRACT Distributed generators are normally operated in automatic power factor-constrained bi- directional power flow may cause unacceptable voltage fluctuations that would cause generator

  10. Microsoft PowerPoint - ACS_Nano-Strelcov_2013.pptx

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHighand Retrievals fromprocess usedGELustre FileBimodal ParticleARM

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

    E-Print Network [OSTI]

    dynamic stability, power system reliability, power system scheduling, power system security, power transmission control, power transmission reliability I . INTRODUCTION Power system stability problems cause many stability problems. Between the power system generation pattern and the load pattern

  12. Voltage/Pitch Control for Maximization and Regulation of Active/Reactive Powers in Wind Turbines with Uncertainties

    E-Print Network [OSTI]

    Guo, Yi; Jiang, John N; Tang, Choon Yik; Ramakumar, Rama G

    2010-01-01T23:59:59.000Z

    This paper addresses the problem of controlling a variable-speed wind turbine with a Doubly Fed Induction Generator (DFIG), modeled as an electromechanically-coupled nonlinear system with rotor voltages and blade pitch angle as its inputs, active and reactive powers as its outputs, and most of the aerodynamic and mechanical parameters as its uncertainties. Using a blend of linear and nonlinear control strategies (including feedback linearization, pole placement, uncertainty estimation, and gradient-based potential function minimization) as well as time-scale separation in the dynamics, we develop a controller that is capable of maximizing the active power in the Maximum Power Tracking (MPT) mode, regulating the active power in the Power Regulation (PR) mode, seamlessly switching between the two modes, and simultaneously adjusting the reactive power to achieve a desired power factor. The controller consists of four cascaded components, uses realistic feedback signals, and operates without knowledge of the C_p-...

  13. Precision voltage regulation on the 5 kHz, 3. 125 MW ETA-II pulsed power system

    SciTech Connect (OSTI)

    Watson, J.A.; Payne, A.N.; Sampayan, S.E.; Ollis, C.W.

    1991-06-01T23:59:59.000Z

    Each of four pulsed power units (PPUs) for the Experimental Test Accelerator 2 (ETA-2) at Lawrence Livermore National Laboratory delivers a 25kV, 20kA, 4{mu}S pulse at a 5kHz repetition rate into a magnetic pulse compression modulator (MAG-1D). In our present configuration, we are capable of producing a 50 pulse burst using a 1000{mu}F capacitor bank. In this configuration, the input voltage to the PPU droops 22% during the burst. Accelerator operating requirements, however, dictate {plus minus}0.1% regulation of the PPU output voltage during the burst. We are employing a de-Qing network to achieve this regulation goal. In this paper, we describe an output voltage predict-ahead scheme that we are using to generate de-Q trigger pulses at the proper time to insure accurate regulations. 8 refs., 5 figs.

  14. ESBWR response to an extended station blackout/loss of all AC power

    SciTech Connect (OSTI)

    Barrett, A. J.; Marquino, W. [New Plants Engineering, GE Hitachi Nuclear Energy, M/CA 75, 3901 Castle Hayne Road, Wilmington, NC 28402 (United States)

    2012-07-01T23:59:59.000Z

    U.S. federal regulations require light water cooled nuclear power plants to cope with Station Blackouts for a predetermined amount of time based on design factors for the plant. U.S. regulations define Station Blackout (SBO) as a loss of the offsite electric power system concurrent with turbine trip and unavailability of the onsite emergency AC power system. According to U.S. regulations, typically the coping period for an SBO is 4 hours and can be as long as 16 hours for currently operating BWR plants. Being able to cope with an SBO and loss of all AC power is required by international regulators as well. The U.S. licensing basis for the ESBWR is a coping period of 72 hours for an SBO based on U.S. NRC requirements for passive safety plants. In the event of an extended SBO (viz., greater than 72 hours), the ESBWR response shows that the design is able to cope with the event for at least 7 days without AC electrical power or operator action. ESBWR is a Generation III+ reactor design with an array of passive safety systems. The ESBWR primary success path for mitigation of an SBO event is the Isolation Condenser System (ICS). The ICS is a passive, closed loop, safety system that initiates automatically on a loss of power. Upon Station Blackout or loss of all AC power, the ICS begins removing decay heat from the Reactor Pressure Vessel (RPV) by (i) condensing the steam into water in heat exchangers located in pools of water above the containment, and (ii) transferring the decay heat to the atmosphere. The condensed water is then returned by gravity to cool the reactor again. The ICS alone is capable of maintaining the ESBWR in a safe shutdown condition after an SBO for an extended period. The fuel remains covered throughout the SBO event. The ICS is able to remove decay heat from the RPV for at least 7 days and maintains the reactor in a safe shutdown condition. The water level in the RPV remains well above the top of active fuel for the duration of the SBO event. Beyond 7 days, only a few simple actions are needed to cope with the SBO for an indefinite amount of time. The operation of the ICS as the primary success path for mitigation of an SBO, allows for near immediate plant restart once power is restored. (authors)

  15. New Power Electronics Converter Interfacing a Hybrid Dc/Ac Microgrid M. Alibeik, E. C. dos Santos Jr.

    E-Print Network [OSTI]

    Zhou, Yaoqi

    New Power Electronics Converter Interfacing a Hybrid Dc/Ac Microgrid M. Alibeik, E. C. dos Santos microgrid is that it has higher efficiency and lesser power conversion. In this work is proposed a new integrated power electronics converter able to connect a Distributed Generation (DG) unit with a hybrid dc

  16. Power superconducting power transmission cable

    DOE Patents [OSTI]

    Ashworth, Stephen P. (Cambridge, GB)

    2003-01-01T23:59:59.000Z

    The present invention is for a compact superconducting power transmission cable operating at distribution level voltages. The superconducting cable is a conductor with a number of tapes assembled into a subconductor. These conductors are then mounted co-planarly in an elongated dielectric to produce a 3-phase cable. The arrangement increases the magnetic field parallel to the tapes thereby reducing ac losses.

  17. Impact of Increasing Distributed Wind Power and Wind Turbine Siting on Rural Distribution Feeder Voltage Profiles: Preprint

    SciTech Connect (OSTI)

    Allen, A.; Zhang, Y. C.; Hodge, B. M.

    2013-09-01T23:59:59.000Z

    Many favorable wind energy resources in North America are located in remote locations without direct access to the transmission grid. Building transmission lines to connect remotely-located wind power plants to large load centers has become a barrier to increasing wind power penetration in North America. By connecting utility-sized megawatt-scale wind turbines to the distribution system, wind power supplied to consumers could be increased greatly. However, the impact of including megawatt-scale wind turbines on distribution feeders needs to be studied. The work presented here examined the impact that siting and power output of megawatt-scale wind turbines have on distribution feeder voltage. This is the start of work to present a general guide to megawatt-scale wind turbine impact on the distribution feeder and finding the amount of wind power that can be added without adversely impacting the distribution feeder operation, reliability, and power quality.

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

    SciTech Connect (OSTI)

    None

    2012-01-25T23:59:59.000Z

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

  19. IEEE Trans. Power Systems, Vol. 14, No. 1, February 1999, pp. 158-165. Analysis of SVC and TCSC Controllers in Voltage Collapse

    E-Print Network [OSTI]

    Cańizares, Claudio A.

    |This paper presents detailed steady-state mod- els with controls of two Flexible AC Transmission System FACTS to increase the maximum transfer capabili- ties of power networks 11 . With the improvements in current of Flexible AC Transmission Systems FACTS, the possi- bility has arisen of using di erent types of controllers

  20. The Use of Power Sums to Solve the Harmonic Elimination Equations for Multilevel Converters EPE Journal Vol. 15 no

    E-Print Network [OSTI]

    Tolbert, Leon M.

    sources (solar cells, fuel cells, the rectified output of wind turbines) to an existing ac power grid of solar cells are dc voltages, and if this energy is to be fed to into an ac power grid, a powerThe Use of Power Sums to Solve the Harmonic Elimination Equations for Multilevel Converters EPE

  1. High power impulse magnetron sputtering: Current-voltage-time characteristics indicate the onset of sustained self-sputtering

    E-Print Network [OSTI]

    Anders, Andre; Andersson, Joakim; Ehiasarian, Arutiun

    2008-01-01T23:59:59.000Z

    target voltage starts to slightly droop for higher voltages,1000 V, the actual voltage droops and shows less stability.see a large voltage droop, especially at high current). We

  2. Proc. International Symposium on Circuits and Systems (ISCAS), vol. 5, pp 653 -656, Geneva (Switzerland), May 2000 Low Power/Low Voltage High Speed CMOS Differential

    E-Print Network [OSTI]

    Fayomi, Christian

    @vlsi.polymtl.ca ABSTRACT A new CMOS differential latched comparator suitable for low voltage, low-power application domains. At the same time, designing analog circuits that can operate from a low-voltage supply on a single ended design configuration. It consists of two operational transconductance amplifiers (NMOS

  3. Impact of high-power stress on dynamic ON-resistance of high-voltage GaN HEMTs Donghyun Jin

    E-Print Network [OSTI]

    del Alamo, Jesús A.

    Impact of high-power stress on dynamic ON-resistance of high-voltage GaN HEMTs Donghyun Jin-resistance (RON) in high- voltage GaN High-Electron-Mobility Transistors (HEMTs). We use a newly proposed dynamic. All rights reserved. 1. Introduction In the last decade, GaN Field-Effect Transistors have emerged

  4. Utility-Scale Silicon Carbide Semiconductor: Monolithic Silicon Carbide Anode Switched Thyristor for Medium Voltage Power Conversion

    SciTech Connect (OSTI)

    None

    2010-09-01T23:59:59.000Z

    ADEPT Project: GeneSiC is developing an advanced silicon-carbide (SiC)-based semiconductor called an anode-switched thyristor. This low-cost, compact SiC semiconductor conducts higher levels of electrical energy with better precision than traditional silicon semiconductors. This efficiency will enable a dramatic reduction in the size, weight, and volume of the power converters and electronic devices it's used in.GeneSiC is developing its SiC-based semiconductor for utility-scale power converters. Traditional silicon semiconductors can't process the high voltages that utility-scale power distribution requires, and they must be stacked in complicated circuits that require bulky insulation and cooling hardware. GeneSiC's semiconductors are well suited for high-power applications like large-scale renewable wind and solar energy installations.

  5. Damping of a parallel ac-dc power system using PID power system stabilizers and rectifier current regulators

    SciTech Connect (OSTI)

    Hsu, Y.Y.; Wang, L. (Dept. of Electrical Engineering, National Taiwan Univ., Taipei (TW))

    1988-09-01T23:59:59.000Z

    A novel approach is presented to improve the dynamic stability of a parallel AC-DC power system. The developed scheme employs a proportional-integral-derivative (PID) power system stabilizer (PSS) and a PID rectifier current regulator (RCR) to enhance the damping for the electromagnetical mode of the system. The parameters of the proposed PID controllers are determined using a unified approach based on modal control theory. Eigenvalue analyses are performed for the system under various operating conditions in order to compare the damping effects provided by the two different control schemes. To demonstrate the effectiveness of the proposed damping schemes under disturbance conditions simulated dynamic response tests based on a nonlinear system model are also performed.

  6. Current-voltage-time characteristics of the reactive Ar/N{sub 2} high power impulse magnetron sputtering discharge

    SciTech Connect (OSTI)

    Magnus, F.; Sveinsson, O. B.; Olafsson, S. [Science Institute, University of Iceland, Dunhaga 3, Reykjavik IS-107 (Iceland); Gudmundsson, J. T. [Science Institute, University of Iceland, Dunhaga 3, Reykjavik IS-107 (Iceland); University of Michigan-Shanghai Jiao Tong University Joint Institute, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai 200240 (China)

    2011-10-15T23:59:59.000Z

    The discharge current and voltage waveforms have been measured in a reactive high power impulse magnetron sputtering (HiPIMS) Ar/N{sub 2} discharge with a Ti target for 400 {mu}s long pulses. We observe that the current waveform in the reactive Ar/N{sub 2} HiPIMS discharge is highly dependent on the pulse repetition frequency, unlike the non-reactive Ar discharge. The current is found to increase significantly as the frequency is lowered. This is attributed to an increase in the secondary electron emission yield during the self-sputtering phase, when the nitride forms on the target at low frequencies. In addition, self-sputtering runaway occurs at lower discharge voltages when nitrogen is added to the discharge. This illustrates the crucial role of self-sputtering in the behavior of the reactive HiPIMS discharge.

  7. AC Loss Measurements on a 2G YBCO Coil

    SciTech Connect (OSTI)

    Rey, Christopher M [ORNL] [ORNL; Duckworth, Robert C [ORNL] [ORNL; Schwenterly, S W [ORNL] [ORNL

    2011-01-01T23:59:59.000Z

    The Oak Ridge National Laboratory (ORNL) is collaborating with Waukesha Electric Systems (WES) to continue development of HTS power transformers. For compatibility with the existing power grid, a commercially viable HTS transformer will have to operate at high voltages in the range of 138 kV and above, and will have to withstand 550-kV impulse voltages as well. Second-generation (2G) YBCO coated conductors will be required for an economically-competitive design. In order to adequately size the refrigeration system for these transformers, the ac loss of these HTS coils must be characterized. Electrical AC loss measurements were conducted on a prototype high voltage (HV) coil with co-wound stainless steel at 60 Hz in a liquid nitrogen bath using a lock-in amplifier technique. The prototype HV coil consisted of 26 continuous (without splice) single pancake coils concentrically centered on a stainless steel former. For ac loss measurement purposes, voltage tap pairs were soldered across each set of two single pancake coils so that a total of 13 separate voltage measurements could be made across the entire length of the coil. AC loss measurements were taken as a function of ac excitation current. Results show that the loss is primarily concentrated at the ends of the coil where the operating fraction of critical current is the highest and show a distinct difference in current scaling of the losses between low current and high current regimes.

  8. Effect of AC target power on AlN film quality

    SciTech Connect (OSTI)

    Knisely, Katherine, E-mail: kknisely@umich.edu; Grosh, Karl [Department of Mechanical Engineering, University of Michigan, 2026 GG Brown—2350 Hayward St., Ann Arbor, Michigan 48109 (United States)

    2014-09-01T23:59:59.000Z

    The influence of alternating current (AC) target power on film stress, roughness, and x-ray diffraction rocking curve full width half maximum (FWHM) was examined for AlN films deposited using S-gun magnetron sputtering on insulative substrates consisting of Si wafers with 575?nm thermal oxide. As the AC target power was increased from 5 to 8?kW, the deposition rate increased from 9.3 to 15.9?A/s, film stress decreased from 81 to ?170?MPa, and the rocking curve FWHM increased from 0.98 to 1.03°. AlN film behavior is observed to change with target life; films deposited at 200?kWh target life were approximately 40?MPa more compressive and had 0.02° degree higher rocking curve FWHM values than films deposited at 130?kWh. AlN films deposited in two depositions were compared with films deposited in a single deposition, in order to better characterize the growth behavior and properties of AlN films deposited on an existing AlN film, which is not well understood. Two deposition films, when compared with single deposition films, showed no variation in residual stress trends or grain size behavior, but the average film roughness increased from 0.7 to 1.4?nm and rocking curve FWHM values increased by more than 0.25°.

  9. On Reactive Power Flow and Voltage Stability in Microgrids Basilio Gentile, John W. Simpson-Porco, Florian Dorfler, Sandro Zampieri, and Francesco Bullo

    E-Print Network [OSTI]

    Bullo, Francesco

    ], where an approximate solution to the reactive power flow equations was developed for electrical networksOn Reactive Power Flow and Voltage Stability in Microgrids Basilio Gentile, John W. Simpson-Porco, Florian D¨orfler, Sandro Zampieri, and Francesco Bullo Abstract-- This paper focuses on reactive power

  10. G,ANIl. D.i`. POWER CON'JERTFRS : IMPROVEMENTS OF TiiE RESPONSE TO MAINS FLIJ,'T[JATION.?. MAINS VOLTAGE HARMONIC F`ILTERTNC

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    to The average duration being in the order of .2 locate faults inside the power supplies ar.d to fix the to .4- vements were only possible due to the fact that the power transformers had a sufficient voltage margin. in1053 G,ANIl. D.i`. POWER CON'JERTFRS : IMPROVEMENTS OF TiiE RESPONSE TO MAINS FLIJ

  11. Power Attack Resistant Cryptosystem Design: A Dynamic Voltage and Frequency Switching Approach

    E-Print Network [OSTI]

    Boyer, Edmond

    studied by several groups. Power attacks, which infer program behavior from observing power supply current (DPA), which identifies cryptographic keys by monitoring processor power supply current, is a very real analysis [7], power analysis [1], electromagnetic analysis [8] and fault induction [9]. Here, we are most

  12. A DSP based real time power quality measurement system with voltage distortion improvement capability

    E-Print Network [OSTI]

    Gou, Jian

    1992-01-01T23:59:59.000Z

    . (August 1992) Jian Gou, B. S. E. E. , Shanghai Jiao Tong Ilniversity Chair of Advisory Committee. Dr. P. Enjeti The general drive towards automation has increased the use of harmonic generating loads both by residential as well as industrial consumers... The examples of these loads in home and industry are: heating ventilation and air conditioning equipment (HVAC); electric kitchen apphances; electric arc furnaces; variable speed dc and ac drives, etc Since the equipment of this kind provides the users...

  13. Control method for peak power delivery with limited DC-bus voltage

    DOE Patents [OSTI]

    Edwards, John; Xu, Longya; Bhargava, Brij B.

    2006-09-05T23:59:59.000Z

    A method for driving a neutral point-clamped multi-level voltage source inverter supplying a synchronous motor is provided. A DC current is received at a neutral point-clamped multi-level voltage source inverter. The inverter has first, second, and third output nodes. The inverter also has a plurality of switches. A desired speed of a synchronous motor connected to the inverter by the first second and third nodes is received by the inverter. The synchronous motor has a rotor and the speed of the motor is defined by the rotational rate of the rotor. A position of the rotor is sensed, current flowing to the motor out of at least two of the first, second, and third output nodes is sensed, and predetermined switches are automatically activated by the inverter responsive to the sensed rotor position, the sensed current, and the desired speed.

  14. Verification of voltage/frequency requirement for emergency diesel generator in nuclear power plant using dynamic modeling

    SciTech Connect (OSTI)

    Hur, Jin-Suk; Roh, Myung- Sub [KEPCO International Nuclear Graduate School, 1456-1 Shinam-ri, Seosaeng-myeon, Ulju-gun, Ulsan, 689-882 (Korea, Republic of)

    2014-02-12T23:59:59.000Z

    One major cause of the plant shutdown is the loss of electrical power. The study is to comprehend the coping action against station blackout including emergency diesel generator, sequential loading of safety system and to ensure that the emergency diesel generator should meet requirements, especially voltage and frequency criteria using modeling tool. This paper also considered the change of the sequencing time and load capacity only for finding electrical design margin. However, the revision of load list must be verified with safety analysis. From this study, it is discovered that new load calculation is a key factor in EDG localization and in-house capability increase.

  15. Adjustable Speed AC Motor Drives-Applications Problems

    E-Print Network [OSTI]

    Enjeti, P.

    Adjustable Speed AC Motor Drives Applications Problems by Dr. P. Enjeti Power Quality Laboratory Department ofElectrical Engineering Texas A&M University College Station, TX 77843 Tel: 409-845-7466 Fax: 409-845-6259 Email..., it generates side effects, some which have been recognized only recently. This paper presents a comprehensive coverage of application issues of PWM inverter controlled ac motor drives which include damage to motor insulation due to reflected voltages caused...

  16. Voltage Control Technical Conference

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Intro Voltage Control Conference - BPA Active Power Control in Wind Parks - Siemens Interconnection Criteria for Frequency Response Requirements - NERC Model Validation...

  17. Charging a Battery-Powered Device with a Fiber-Optically Connected Photonic Power System for Achieving High-Voltage Isolation

    SciTech Connect (OSTI)

    Lizon, David C [Los Alamos National Laboratory; Gioria, Jack G [Los Alamos National Laboratory; Dale, Gregory E [Los Alamos National Laboratory; Snyder, Hans R [Los Alamos National Laboratory

    2008-01-01T23:59:59.000Z

    This paper describes the development and testing of a system to provide isolated power to the cathode-subsystem electronics of an x-ray tube. These components are located at the cathode potential of several hundred kilovolts, requiring a supply of power isolated from this high voltage. In this design a fiber-optically connected photonic power system (PPS) is used to recharge a lithium-ion battery pack, which will subsequently supply power to the cathode-subsystem electronics. The suitability of the commercially available JDSU PPS for this application is evaluated. The output of the ppe converter is characterized. The technical aspects of its use for charging a variety of Li-Ion batteries are discussed. Battery charge protection requirements and safety concerns are also addressed.

  18. Design of low-voltage, high-bandwidth radio frequency power converters

    E-Print Network [OSTI]

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

    2012-01-01T23:59:59.000Z

    The mass and volume required for power electronics circuitry is a dominant obstacle to the miniaturization and integration of many systems. Likewise, power electronics with greater bandwidth and efficiency are becoming ...

  19. Multilevel cascade voltage source inverter with seperate DC sources

    DOE Patents [OSTI]

    Peng, Fang Zheng (Knoxville, TN); Lai, Jih-Sheng (Blacksburg, VA)

    2002-01-01T23:59:59.000Z

    A multilevel cascade voltage source inverter having separate DC sources is described herein. This inverter is applicable to high voltage, high power applications such as flexible AC transmission systems (FACTS) including static VAR generation (SVG), power line conditioning, series compensation, phase shifting and voltage balancing and fuel cell and photovoltaic utility interface systems. The M-level inverter consists of at least one phase wherein each phase has a plurality of full bridge inverters equipped with an independent DC source. This inverter develops a near sinusoidal approximation voltage waveform with only one switching per cycle as the number of levels, M, is increased. The inverter may have either single-phase or multi-phase embodiments connected in either wye or delta configurations.

  20. Multilevel cascade voltage source inverter with seperate DC sources

    DOE Patents [OSTI]

    Peng, Fang Zheng (Oak Ridge, TN); Lai, Jih-Sheng (Knoxville, TN)

    1997-01-01T23:59:59.000Z

    A multilevel cascade voltage source inverter having separate DC sources is described herein. This inverter is applicable to high voltage, high power applications such as flexible AC transmission systems (FACTS) including static VAR generation (SVG), power line conditioning, series compensation, phase shifting and voltage balancing and fuel cell and photovoltaic utility interface systems. The M-level inverter consists of at least one phase wherein each phase has a plurality of full bridge inverters equipped with an independent DC source. This inverter develops a near sinusoidal approximation voltage waveform with only one switching per cycle as the number of levels, M, is increased. The inverter may have either single-phase or multi-phase embodiments connected in either wye or delta configurations.

  1. Multilevel cascade voltage source inverter with seperate DC sources

    DOE Patents [OSTI]

    Peng, Fang Zheng; Lai, Jih-Sheng

    2001-04-03T23:59:59.000Z

    A multilevel cascade voltage source inverter having separate DC sources is described herein. This inverter is applicable to high voltage, high power applications such as flexible AC transmission systems (FACTS) including static VAR generation (SVG), power line conditioning, series compensation, phase shifting and voltage balancing and fuel cell and photovoltaic utility interface systems. The M-level inverter consists of at least one phase wherein each phase has a plurality of full bridge inverters equipped with an independent DC source. This inverter develops a near sinusoidal approximation voltage waveform with only one switching per cycle as the number of levels, M, is increased. The inverter may have either single-phase or multi-phase embodiments connected in either wye or delta configurations.

  2. Multilevel cascade voltage source inverter with separate DC sources

    DOE Patents [OSTI]

    Peng, F.Z.; Lai, J.S.

    1997-06-24T23:59:59.000Z

    A multilevel cascade voltage source inverter having separate DC sources is described herein. This inverter is applicable to high voltage, high power applications such as flexible AC transmission systems (FACTS) including static VAR generation (SVG), power line conditioning, series compensation, phase shifting and voltage balancing and fuel cell and photovoltaic utility interface systems. The M-level inverter consists of at least one phase wherein each phase has a plurality of full bridge inverters equipped with an independent DC source. This inverter develops a near sinusoidal approximation voltage waveform with only one switching per cycle as the number of levels, M, is increased. The inverter may have either single-phase or multi-phase embodiments connected in either wye or delta configurations. 15 figs.

  3. Price Discovery in Dynamic Power Markets with Low-Voltage Distribution-Network Participants

    E-Print Network [OSTI]

    Caramanis, Michael

    but not least distribution network rent. Keywords-distribution network locational marginal prices; power flow application to Electric Power [2, 3] dynamic Locational-Marginal-Price (LMP) based Wholesale Power Markets load-side market participation and the use of Distribution network Locational Marginal Prices (DLMP

  4. Automatic voltage imbalance detector

    DOE Patents [OSTI]

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

    1984-01-01T23:59:59.000Z

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

  5. Dynamic performance of a STATCON at an HVDC inverter feeding a very weak AC system

    SciTech Connect (OSTI)

    Zhuang, Y.; Menzies, R.W. [Univ. of Manitoba, Winnipeg, Manitoba (Canada)] [Univ. of Manitoba, Winnipeg, Manitoba (Canada); Nayak, O.B. [HVDC Research Centre, Winnipeg, Manitoba (Canada)] [HVDC Research Centre, Winnipeg, Manitoba (Canada); Turanli, H.M. [Manitoba Hydro, Winnipeg, Manitoba (Canada)] [Manitoba Hydro, Winnipeg, Manitoba (Canada)

    1996-04-01T23:59:59.000Z

    This paper investigates the dynamic performance of the advanced static var compensator or STATCON at a high voltage direct current (HVDC) converter terminal where the ac system has a very low short circuit ratio (SCR). The STATCON is based on a nine-level GTO thyristor inverter. The studies include operating characteristics of the STATCON under various ac and dc disturbances. The simulation results are compared with other types of reactive power compensation options available for such applications. It is shown that the STATCON has clear advantages over the other compensators, in areas such as; fault response time, voltage support ability, and dc recovery, while operating with very weak ac systems.

  6. Study of static reactive power compensators for high-voltage power systems. Final report, May 12, 1981

    SciTech Connect (OSTI)

    Byerly, R.T.; Bennon, R.J.; Taylor, E.R. Jr.; Poznaniak, D.T.

    1981-05-12T23:59:59.000Z

    A general study of the application of static VAR compensators (SVC's) to high-voltage transmission systems has been performed. Considerable emphasis has been placed on improvements to synchronous stability, and it is shown that SVC's can provide significant benefits in terms of damping for unstable modes of oscillation and increases in transient stability limits. This report includes descriptions of static VAR compensators, technical and economic comparisons of different compensators, compensator models for system studies, comprehensive study procedures, study results for two small-scale systems, and guidelines for SVC application.

  7. Experimental Validation of Voltage-Based State-of-Charge Algorithm for Power Batteries

    E-Print Network [OSTI]

    Jia, Zhuo

    2013-01-01T23:59:59.000Z

    for nickel metal hydride batteries including hysteresis” ,Control of Lithium-Ion Batteries”, Control Systems, IEEE,modeling of lead acid batteries”, Applied Power Electronics

  8. Comparison of 3 Self-Starting Step-Up DC:DC Converter Topologies for Harvesting Energy from Low-Voltage and Low-Power Microbial Fuel Cells

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    -Voltage and Low-Power Microbial Fuel Cells Nicolas Degrenne1, Bruno Allard2, François Buret1, Florent Morel1.surname@ec-lyon.fr, 2firstname.surname@insa-lyon.fr Keywords «Fuel cell system», , «switched-mode power supply are made according to specifications issued from the stringent characteristics of microbial fuel cells

  9. IEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 23, NO. 1, JANUARY 2008 495 Adaptive Modulation Control for Multiple-Phase Voltage Regulators

    E-Print Network [OSTI]

    Wu, Shin-Tson

    ) Interleaved operation waveforms. (b) Bode plot of power stage. For some advanced control schemes like adaptiveIEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 23, NO. 1, JANUARY 2008 495 Adaptive Modulation Control for Multiple-Phase Voltage Regulators Shangyang Xiao, Weihong Qiu, Greg Miller, Thomas X. Wu

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

    SciTech Connect (OSTI)

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

    2006-08-01T23:59:59.000Z

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

  11. Ac-Ac Dual Active Bridge Converter for Solid State Transformer

    E-Print Network [OSTI]

    Kimball, Jonathan W.

    flow. The advantages of direct ac-ac conversion include fewer power conversion stages and minimized single-stage direct ac-ac power conversion to an SST. Fewer conversion stages reduce conduction loss) converter in direct ac-ac power conversion. Like a DAB converter as dc-dc power supply in [5] and [6

  12. Design of programmable, low power, low dropout voltage regulators for portable applications

    E-Print Network [OSTI]

    Islas Ohlmaier, Abraham

    2007-04-25T23:59:59.000Z

    -Martinez Committee Members, Aydin Karsilayan Karen L. Butler-Purry Rainer Fink Head of Department, Costas Georghiades December 2005 Major Subject: Electrical Engineering iii ABSTRACT Design of Programmable, Low Power, Low...

  13. Low Power Control IC for Efficient High-Voltage Piezoelectric Driving in a Flying Robotic Insect

    E-Print Network [OSTI]

    Wood, Robert

    previously developed power circuits that, when combined, are capable of stepping up a 3.7V Li-poly battery ref- erence, a control register bank, and a serial programming in- terface. Fig. 2 shows a block

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

    E-Print Network [OSTI]

    Ganta, Saikrishna

    2011-10-21T23:59:59.000Z

    Efficency Load q DD I V P I I V ? ? (1.4) Typically the quiescent current of LDO is designed to be less than hundred micro amperes, while the maximum load current can be few hundreds of milliamperes, thus... at maximum loading conditions power efficiency is given by out Efficency DD V P V ? (1.5) Thus for maximum loading conditions power efficiency...

  15. 34 IEEE TRANSACTIONS ON POWER SYSTEMS, VOL. 17, NO. 1, FEBRUARY 2002 Sensitivity of Transfer Capability Margins

    E-Print Network [OSTI]

    Dobson, Ian

    generalizes that practice to more detailed ac power system models that include voltage and re- active power--Optimization, power system control, power system security, power transmission planning, sensitivity. I. INTRODUCTION34 IEEE TRANSACTIONS ON POWER SYSTEMS, VOL. 17, NO. 1, FEBRUARY 2002 Sensitivity of Transfer

  16. High voltage power supply systems for electron beam and plasma technologies. Its new element base

    SciTech Connect (OSTI)

    Dermengi, P.G.; Kureghan, A.S.; Pokrovsky, S.V.; Tchvanov, V.A.

    1994-12-31T23:59:59.000Z

    Transforming technique and high voltage technique supplementing each other more and more unite in indivisible constructions of modern apparatuses and systems and applicated in modern technologies providing its high efficiency. Specially worked out, ecologically clean, inertial, inflammable perfluororganic liquid is used in elements and electronic apparatuses simultaneously as insulating and cooling media. This liquid is highly fluid, fills tiny cavities in construction elements and in the places of high concentration of losses, where maximum local overheating of active parts or apparatus constructions takes place, it transforms to boiling state with highly intensive taking off of heat energy from cooled surface point. For instance, being cooled by mentioned perfluororganic liquid, copper wire can conduct current to 50 A/mm{sup 2} density, but in ordinary conditions of transformers, reactors and busses, current density can reach only few Amperes. Possibility of considerable increasing of current density, that is reached by means of intensive cooling, provided by worked out liquid, and taking into account its incredibly high insulating features (liquid has electric strength to 50 KV/mm) allows to provide optimum heat regime of active parts of transformers. reactors, condenser, semiconductor devices, resistors, construction elements and electrotechnical apparatus in general. Particularly high effect of decreasing of weight and dimensions characteristics of elements and electrotechnical apparatus in general can be reached under working out of special constructions of each element and apparatus details, adapted to use of mentioned liquid as insulating and cooling media.

  17. Optimal Reactive Power Dispatch in Real-Time S. Salamat Sharif1

    E-Print Network [OSTI]

    Taylor, James H.

    ) an improvement in the volt- age profile and voltage stability, and 2) a savings in ac- tive power loss of view. A reduction in active power loss gained from ORPD can save a significant amount of money reactive power dispatch, power loss minimization, optimization methods 1 Introduction Optimal power

  18. IEEE PES WM Panel on Modeling, Simulation and Applications of FACTS Controllers in Angle and Voltage Stability Studies, Singapore, Jan. 2000 Power Flow and Transient Stability Models of FACTS Controllers

    E-Print Network [OSTI]

    Cańizares, Claudio A.

    power ow and tran- sient stability studies of such system with its controllers. The latter and Voltage Stability Studies, Singapore, Jan. 2000 Power Flow and Transient Stability Models of FACTS|This paper presents transient stability and power ow models of Thyristor ControlledReactor TCR and Voltage

  19. Bulk power system voltage phenomena -III: Voltage stability, security & control, Davos, Switzerland, August 1994 THE IRRELEVANCE OF LOAD DYNAMICS FOR THE LOADING MARGIN

    E-Print Network [OSTI]

    Dobson, Ian

    instability [11]. Therefore it is useful to compute the location of fold bifurcations of power system models and their sensitivities depend only on the static parts of dynamic power system models. For example, a dynamic power dynamic power system models to be properly understood, the computation of loading mar- gin and its

  20. Abstract: Wind Energy Conversion Systems (WECS) produce fluctuating output power, which may cause voltage fluctuations and

    E-Print Network [OSTI]

    Gross, George

    : An approach to model the solar cell system with coupled multi-physics equations (photovoltaic, electrothermalAbstract: Wind Energy Conversion Systems (WECS) produce fluctuating output power, which may cause in a network of any size can be performed. An algorithm for flicker measurement in the frequency do- main

  1. Peak Power Bi-directional Transfer From High Speed Flywheel to Electrical Regulated Bus Voltage System

    E-Print Network [OSTI]

    Szabados, Barna

    life cycle. A reduced life cycle will translate into high maintenance costs since the batteries have devices capable of a minimum power of 400 W/kg, energy of 200 Wh/kg, a life cycle of 2500 at a cost vehicle during both acceleration and regenerative braking. The life cycle of the electric vehicle

  2. Electrical power inverter having a phase modulated, twin-inverter, high frequency link and an energy storage module

    DOE Patents [OSTI]

    Pitel, Ira J. (Whippany, NJ)

    1987-02-03T23:59:59.000Z

    The present invention provides an electrical power inverter method and apparatus, which includes a high frequency link, for converting DC power into AC power. Generally stated, the apparatus includes a first high frequency module which produces an AC voltage at a first output frequency, and a second high frequency inverter module which produces an AC voltage at a second output frequency that is substantially the same as the first output frequency. The second AC voltage is out of phase with the first AC voltage by a selected angular phase displacement. A mixer mixes the first and second output voltages to produce a high frequency carrier which has a selected base frequency impressed on the sidebands thereof. A rectifier rectifies the carrier, and a filter filters the rectified carrier. An output inverter inverts the filtered carrier to produce an AC line voltage at the selected base frequency. A phase modulator adjusts the relative angular phase displacement between the outputs of the first and second high frequency modules to control the base frequency and magnitude of the AC line voltage.

  3. Electrical power inverter having a phase modulated, twin-inverter, high frequency link and an energy storage module

    DOE Patents [OSTI]

    Pitel, I.J.

    1987-02-03T23:59:59.000Z

    The present invention provides an electrical power inverter method and apparatus, which includes a high frequency link, for converting DC power into AC power. Generally stated, the apparatus includes a first high frequency module which produces an AC voltage at a first output frequency, and a second high frequency inverter module which produces an AC voltage at a second output frequency that is substantially the same as the first output frequency. The second AC voltage is out of phase with the first AC voltage by a selected angular phase displacement. A mixer mixes the first and second output voltages to produce a high frequency carrier which has a selected base frequency impressed on the sidebands thereof. A rectifier rectifies the carrier, and a filter filters the rectified carrier. An output inverter inverts the filtered carrier to produce an AC line voltage at the selected base frequency. A phase modulator adjusts the relative angular phase displacement between the outputs of the first and second high frequency modules to control the base frequency and magnitude of the AC line voltage. 19 figs.

  4. Characterization of the Li(Si)/CoS(2) couple for a high-voltage, high-power thermal battery

    SciTech Connect (OSTI)

    GUIDOTTI,RONALD A.; REINHARDT,FREDERICK W.

    2000-02-01T23:59:59.000Z

    In order to determined the capabilities of a thermal battery with high-voltage and high-power requirements, a detailed characterization of the candidate LiSi/LiCl-LiBr-LiF/CoS{sub 2} electrochemical couple was conducted. The rate capability of this system was investigated using 0.75 inch-dia. and 1.25 inch-dia. single and multiple cells under isothermal conditions, where the cells were regularly pulsed at increasingly higher currents. Limitations of the electronic loads and power supplies necessitated using batteries to obtain the desired maximum current densities possible for this system. Both 1.25 inch-dia. and 3 inch-dia. stacks were used with the number of cells ranging from 5 to 20. Initial tests involved 1.25 inch-dia. cells, where current densities in excess of 15 A/cm{sup 2} (>200 W/cm{sup 2}) were attained with 20-cell batteries during 1-s pulses. In subsequent follow-up tests with 3 inch-dia., 10-cell batteries, ten 400-A 1-s pulses were delivered over an operating period often minutes. These tests formed the foundation for subsequent full-sized battery tests with 125 cells with this chemistry.

  5. Wall-plug (AC) power consumption of a very high energy e+/e- storage ring collider

    E-Print Network [OSTI]

    Ross, Marc C

    2013-01-01T23:59:59.000Z

    Estimated AC power consumption ranges from ~280 MW (1) to 416 MW (2) for a 350 GeV E_cm 80 km circumference colliding beam storage ring complex with parameters given in (1). The difference between the two estimates is from differing assumptions concerning heat removal, cryo-plant efficiency, klystron operation etc. The purpose of this note is to list and explain these. (1) Mike Koratzinos, et al, IPAC13 (2) Marc Ross, Higgs Quo Vadis Workshop, March 2013.

  6. Bonneville Power Administration is investigating wide-area stability and voltage control. The control provides a flexible

    E-Print Network [OSTI]

    Venkatasubramanian, Mani V.

    consists of a ±500-kV, 3100 MW bipolar HVDC link, and a 500-kV AC intertie of 4800 MW capacity. Measures

  7. System and Battery Charge Control for PV-Powered AC Lighting Systems

    SciTech Connect (OSTI)

    Kern, G.

    1999-04-01T23:59:59.000Z

    This report reviews a number of issues specific to stand-alone AC lighting systems. A review of AC lighting technology is presented, which discusses the advantages and disadvantages of various lamps. The best lamps for small lighting systems are compact fluorescent. The best lamps for intermediate-size systems are high- or low-pressure sodium. Specifications for battery charging and load control are provided with the goal of achieving lamp lifetimes on the order of 16,000 to 24,000 hours and battery lifetimes of 4 to 5 years. A rough estimate of the potential domestic and global markets for stand-alone AC lighting systems is presented. DC current injection tests were performed on high-pressure sodium lamps and the test results are presented. Finally, a prototype system was designed and a prototype system controller (with battery charger and DC/AC inverter) was developed and built.

  8. Boosting the voltage of a salinity-gradient-power electrochemical cell by means of complex-forming solutions

    E-Print Network [OSTI]

    Carati, Andrea

    the diaphragm constitutes a waste of free energy, which impairs the voltage generation of the concentration cell-based light-emitting electrochemical cells J. Appl. Phys. 116, 104504 (2014); 10.1063/1.4895060 Decoupled luminance decay and voltage drift in polymer light-emitting electrochemical cells: Forward bias vs. reverse

  9. ac josephson effect: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    in the dc mass currents voltage, a high frequency ac voltage is applied across a superconduct- ing Josephson junction, the dc, Dm 22eV, application of a dc voltage produces...

  10. Experimental validation of a high voltage pulse measurement method.

    SciTech Connect (OSTI)

    Cular, Stefan; Patel, Nishant Bhupendra; Branch, Darren W.

    2013-09-01T23:59:59.000Z

    This report describes X-cut lithium niobate's (LiNbO3) utilization for voltage sensing by monitoring the acoustic wave propagation changes through LiNbO3 resulting from applied voltage. Direct current (DC), alternating current (AC) and pulsed voltage signals were applied to the crystal. Voltage induced shift in acoustic wave propagation time scaled quadratically for DC and AC voltages and linearly for pulsed voltages. The measured values ranged from 10 - 273 ps and 189 ps - 2 ns for DC and non-DC voltages, respectively. Data suggests LiNbO3 has a frequency sensitive response to voltage. If voltage source error is eliminated through physical modeling from the uncertainty budget, the sensor's U95 estimated combined uncertainty could decrease to ~0.025% for DC, AC, and pulsed voltage measurements.

  11. Design considerations for large space electric power systems

    SciTech Connect (OSTI)

    Renz, D.D.; Finke, R.C.; Stevens, N.J.; Triner, J.E.; Hansen, I.G.

    1983-04-01T23:59:59.000Z

    As power levels of spacecraft rise to the 50 to 100 kW range, it becomes apparent that low voltage (28 V) dc power distribution and management systems will not operate efficiently at these higher power levels. The concept of transforming a solar array voltage at 150 V dc into a 1000 V ac distribution system operating at 20 kHz is examined. The transformation is accomplished with series-resonant inverter by using a rotary transformer to isolate the solar array from the spacecraft. The power can then be distributed in any desired method such as three phase delta to delta. The distribution voltage can be easily transformed to any desired load voltage and operating frequency. The reasons for the voltage limitations on the solar array due to plasma interactions and the many advantages of a high voltage, high frequency at distribution system are discussed.

  12. Comparison of Two Autonomous AC-DC Converters for Piezoelectric Energy Scavenging Systems

    E-Print Network [OSTI]

    Boyer, Edmond

    - 1 - Comparison of Two Autonomous AC-DC Converters for Piezoelectric Energy Scavenging Systems E Cornaredo, Milan, Italy Abstract - Piezoelectric Energy Scavenging Systems (PESS) are used to convert of the output voltage of these transducers is needed. Since the output power level of the energy transducer can

  13. Voltage verification unit

    DOE Patents [OSTI]

    Martin, Edward J. (Virginia Beach, VA)

    2008-01-15T23:59:59.000Z

    A voltage verification unit and method for determining the absence of potentially dangerous potentials within a power supply enclosure without Mode 2 work is disclosed. With this device and method, a qualified worker, following a relatively simple protocol that involves a function test (hot, cold, hot) of the voltage verification unit before Lock Out/Tag Out and, and once the Lock Out/Tag Out is completed, testing or "trying" by simply reading a display on the voltage verification unit can be accomplished without exposure of the operator to the interior of the voltage supply enclosure. According to a preferred embodiment, the voltage verification unit includes test leads to allow diagnostics with other meters, without the necessity of accessing potentially dangerous bus bars or the like.

  14. 650 IEEE TRANSACTIONS ON POWER DELIVERY, VOL. 26, NO. 2, APRIL 2011 Hourly Scheduling of DC Transmission Lines in

    E-Print Network [OSTI]

    Fu, Yong

    Transmission Lines in SCUC With Voltage Source Converters Azim Lotfjou, Mohammad Shahidehpour, Fellow, IEEE transmission lines, se- curity-constrained unit commitment, voltage-source converters. NOMENCLATURE Index of ac;LOTFJOU et al.: HOURLY SCHEDULING OF DC TRANSMISSION LINES 651 , Vector of real and reactive power

  15. Isolated and soft-switched power converter

    DOE Patents [OSTI]

    Peng, Fang Zheng (Knoxville, TN); Adams, Donald Joe (Knoxville, TN)

    2002-01-01T23:59:59.000Z

    An isolated and soft-switched power converter is used for DC/DC and DC/DC/AC power conversion. The power converter includes two resonant tank circuits coupled back-to-back through an isolation transformer. Each resonant tank circuit includes a pair of resonant capacitors connected in series as a resonant leg, a pair of tank capacitors connected in series as a tank leg, and a pair of switching devices with anti-parallel clamping diodes coupled in series as resonant switches and clamping devices for the resonant leg. The power converter is well suited for DC/DC and DC/DC/AC power conversion applications in which high-voltage isolation, DC to DC voltage boost, bidirectional power flow, and a minimal number of conventional switching components are important design objectives. For example, the power converter is especially well suited to electric vehicle applications and load-side electric generation and storage systems, and other applications in which these objectives are important. The power converter may be used for many different applications, including electric vehicles, hybrid combustion/electric vehicles, fuel-cell powered vehicles with low-voltage starting, remote power sources utilizing low-voltage DC power sources, such as photovoltaics and others, electric power backup systems, and load-side electric storage and generation systems.

  16. Distribution System Voltage Performance Analysis for High-Penetration Photovoltaics

    SciTech Connect (OSTI)

    Liu, E.; Bebic, J.

    2008-02-01T23:59:59.000Z

    This report examines the performance of commonly used distribution voltage regulation methods under reverse power flow.

  17. Methods, systems and apparatus for controlling operation of two alternating current (AC) machines

    DOE Patents [OSTI]

    Gallegos-Lopez, Gabriel (Torrance, CA); Nagashima, James M. (Cerritos, CA); Perisic, Milun (Torrance, CA); Hiti, Silva (Redondo Beach, CA)

    2012-06-05T23:59:59.000Z

    A system is provided for controlling two alternating current (AC) machines via a five-phase PWM inverter module. The system comprises a first control loop, a second control loop, and a current command adjustment module. The current command adjustment module operates in conjunction with the first control loop and the second control loop to continuously adjust current command signals that control the first AC machine and the second AC machine such that they share the input voltage available to them without compromising the target mechanical output power of either machine. This way, even when the phase voltage available to either one of the machines decreases, that machine outputs its target mechanical output power.

  18. The Application of Planning to Power Substation Voltage Control Keith Bell, Andrew Coles, Maria Fox, Derek Long and Amanda Smith

    E-Print Network [OSTI]

    Coles, Andrew

    around iterative refinement. 1 Introduction1 The control of electricity distribution is a challenging, a reactive system at the sub- station is used to meet voltage target within this range, set for each time of the day. The reactive system makes use of the adjustable substation components (Wood & Wollenberg 1996

  19. Point of collapse and continuation methods for large ac/dc systems

    SciTech Connect (OSTI)

    Canizares, C.A. (Escuela Politecnica Nacional, Quito (Ecuador)); Alvarado, F.L. (Univ. of Wisconsin, Madison, WI (United States))

    1993-02-01T23:59:59.000Z

    This paper describes the implementation of both Point of Collapse (PoC) methods and continuation methods for the computation of voltage collapse points (saddle-node bifurcations) in large ac/dc systems. A comparison of the performance of these methods is presented for real systems of up to 2,158 buses. The paper discusses computational details of the implementation of the PoC and continuation methods, and the unique challenges encountered due to the presence of high voltage direct current (HVDC) transmission, area interchange power control regulating transformers, and voltage and reactive power limits. The characteristics of a robust PoC power flow program are presented, and its application to detection and solution of voltage stability problems is demonstrated.

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

    E-Print Network [OSTI]

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

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

  1. Equivalent circuits for power system studies on the A-C network calculator

    E-Print Network [OSTI]

    Kolb, Walter Jean

    1948-01-01T23:59:59.000Z

    -sequence network is often as high as 5+ or more of the self-impedance and therefore must be repre- sented on the Calculator to attain the desired accuracy. By definition, zero-sequence line currents and voltages to ground at any point in the system are equal 1n... of transient or subtransient reactance in place of the generator impedance Z in the positive-sequence network, Unbalanced faults necessitate the use of the zero- sequence network and for wye grounded generators the zero- sequence impedance of the generator...

  2. Application of direct pulsewidth modulation scheme to AC-DC converters: - a way to reduce ripple

    E-Print Network [OSTI]

    Zhang, Yuemin

    1993-01-01T23:59:59.000Z

    Modulation (ISPWM), 4 Direct Pulsewidth Modulation (DPWM). 15 5 Single Phase Half Controlled PWM ac-dc Converter . 6 Single Phase Full controlled PWM ac-dc Converter . 18 18 7 Simulation of SPWM ac-dc Converter. 20 8 Output Voltage Spectra of SPWM ac... 30 Balanced Three Phase Inputs 31 Output Voltage of A Three Phase Full Controlled ac-dc SPWM Converter. 42 32 Output Voltage of A Three Phase Full Controlled ac-dc EPWM Con- verter 33 Output Voltage of A Three Phase Full Controlled ac-dc ISPWM Con...

  3. A transistor-only power-efficient high-frequency voltage-mode stimulator for a multichannel system

    E-Print Network [OSTI]

    Serdijn, Wouter A.

    to that of traditional stimulation. The system has a voltage-mode output and therefore safety aspects such as charge operation. dl CRs CCel el S S S 1 2 3 4 S (a) System with parasitics 0 50 100 150 200 250 300 350 -5 -4 -3 is controlled. The simplest model for the tissue is an RC series circuit. In this model the capacitance Cdl

  4. Architectures and circuits for low-voltage energy conversion and applications in renewable energy and power management

    E-Print Network [OSTI]

    Pilawa-Podgurski, Robert C. N

    2012-01-01T23:59:59.000Z

    In this thesis we seek to develop smaller, less expensive, and more efficient power electronics. We also investigate emerging applications where the proper implementation of these new types of power converters can have a ...

  5. automatic regulator voltage: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Rouzbahan 2013-01-01 12 Optimal Distributed Voltage Regulation in Power Distribution Networks CERN Preprints Summary: In this paper, we address the problem of voltage...

  6. A study of Schwarz converters for nuclear powered spacecraft

    SciTech Connect (OSTI)

    Stuart, T.A. [Univ. of Toledo, OH (United States); Schwarze, G.E. [Lewis Research Center, Cleveland, OH (United States)

    1994-09-01T23:59:59.000Z

    High power space systems which use low dc voltage, high current sources such as thermoelectric generators, will most likely require high voltage conversion for transmission purposes. This study considers the use of the Schwarz resonant converter for use as the basic building block to accomplish this low-to-high voltage conversion for either a dc or an ac spacecraft bus. The Schwarz converter has the important assets of both inherent fault tolerance and resonant operation and parallel operation in modular form is possible. A regulated dc spacecraft bus requires only a single stage converter while a constant frequency ac bus requires a cascaded Schwarz converter configuration. If the power system requires constant output power from the dc generator, then a second converter is required to route unneeded power to a ballast load.

  7. A power regulator for the generators on the A.C. network calculator 

    E-Print Network [OSTI]

    Francis, Lawrence Gregg

    1956-01-01T23:59:59.000Z

    LIBRARY A A M COLLEQE OF TEXAS A POWER REGULATOR FOR THE GENERATORS ON THE A. C. NETWORK CALCULATOR A Thesis By Lawrence Gregg Francis Submitted to the Graduate School of the Agricultural and Mechanical College of Teens in partial...

  8. Ancillary service details: Voltage control

    SciTech Connect (OSTI)

    Kirby, B.; Hirst, E.

    1997-12-01T23:59:59.000Z

    Voltage control is accomplished by managing reactive power on an alternating-current power system. Reactive power can be produced and absorbed by both generation and transmission equipment. Reactive-power devices differ substantially in the magnitude and speed of response and in their capital costs. System operators, transmission owners, generators, customers, power marketers, and government regulators need to pay close attention to voltage control as they restructure the U.S. electricity industry. Voltage control can affect reliability and commerce in three ways: (1) Voltages must be maintained within an acceptable range for both customer and power-system equipment to function properly. (2) The movement of reactive power consumes transmission resources, which limits the ability to move real power and worsens congestion. (3) The movement of reactive power results in real-power losses. When generators are required to supply excessive amounts of reactive power, their real-power production must be curtailed. These opportunity costs are not currently compensated for in most regions. Current tariffs are based on embedded costs. These embedded-cost tariffs average about $0.51/MWh, equivalent to $1.5 billion annually for the United States as a whole. Although this cost is low when compared with the cost of energy, it still aggregates to a significant amount of money. This report takes a basic look at why the power system requires reactive power (an appendix explains the fundamentals of real and reactive power). The report then examines the various types of generation and transmission resources used to supply reactive power and to control voltage. Finally it discusses how these resources are deployed and paid for in several reliability regions around the country. As the U.S. electricity industry is restructured, the generation, transmission, and system-control equipment and functions that maintain voltages within the appropriate ranges are being deintegrated.

  9. Low power low-density parity-checking (ldpc) codes decoder design using dynamic voltage and frequency scaling

    E-Print Network [OSTI]

    Wang, Weihuang

    2009-05-15T23:59:59.000Z

    This thesis presents a low-power LDPC decoder design based on speculative scheduling of energy necessary to decode dynamically varying data frame in both block-fading channels and general AWGN channels. A model of a memory-efficient low-power high...

  10. Incorporating HVDC's into monitoring and power system analysis 

    E-Print Network [OSTI]

    Krishnaswamy, Vikram

    2002-01-01T23:59:59.000Z

    system network. Load flow calculates the bus voltage magnitude, phase angle, active and reactive power flows based on loads and generations that are already specified. In this regard, our work presents a better way of solving AC - DC load flow equations...

  11. Microsoft PowerPoint - 2A-C-1-Nagarajan.pptx

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHighand Retrievals fromprocess usedGELustre File Systemi diSanSh

  12. Microsoft PowerPoint - Staff_Science_Highlight-AnPingLi_ACS_Nano.pptx

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHighandSWPA / SPRA / USACE SWPA / SPRA / USACE MarshallWe report27,

  13. Determination of the effect of harmonics on pipe-type power cable AC/DC resistance ratio

    SciTech Connect (OSTI)

    Palmer, J.A.; Degeneff, R.C. (Rensselaer Polytechnic Inst., Troy, NY (United States)); McKernan, T.M.; Halleran, T.M. (Consolidated Edison Co. of NY, Inc., New York (United States))

    1993-03-01T23:59:59.000Z

    This paper presents a closed form expression to compute the AC/CD resistance ratio of HPFF (High Pressure Fluid Filled) pipe-type cable in the presence of harmonics. Industry currently computes this factor, which is a significant part in assessing the current carrying capacity of a system, with the assumption that the currents are purely sinusoidal at 60 Hz. However, as levels of harmonics increase on power systems, concern for the effect of harmonics on system ampacities rises, and that effect has already been discussed for distribution systems. This paper develops a closed form hybrid of the resistance ratio equations presented by Neher and McGrath, and compares the results with measured data at 60 Hz. At present there is no measured data available for the resistance ratio at higher frequencies, so a two dimensional finite element model is developed to view the effect of frequency on the resistance ratio. A discussion is given on the effect of a specific harmonics scenario on the resistance ratio of a given system, and results are presented for some example systems. The paper also discusses the validity and characteristics of each method.

  14. REDUCTION OF VOLTAGE VIOLATIONS FROM EMBEDDED GENERATORS

    E-Print Network [OSTI]

    Harrison, Gareth

    , and on the active and reactive power exported from the local busbar. Line power flow is reduced by local demand be used to attempt to maintain voltage. Recent work has considered the use of embedded diesel generators) If the EG tried to meet an excessive demand for reactive power, as voltage continued to fall, the AVR could

  15. Soft switched high frequency ac-link converter 

    E-Print Network [OSTI]

    Balakrishnan, Anand Kumar

    2009-05-15T23:59:59.000Z

    topology for medium and high power ac-ac, ac-dc and dc-ac applications. An ac-link formed by an inductor-capacitor pair replaces the conventional dc-link. Each leg of the converter is formed by two bidirectional switches. Power transfer from input to output...

  16. A Matter of Quantum Voltages

    SciTech Connect (OSTI)

    Sellner, Bernhard; Kathmann, Shawn M.

    2014-11-14T23:59:59.000Z

    Voltages inside matter are relevant to crystallization, materials science, biology, catalysis, and aqueous chemistry. Electron holography is able to measure the variation of voltages in matter and modern supercomputers allow the calculation of quantum voltages with practically unlimited spatial and temporal resolution of bulk systems. Of particular interest is the Mean Inner Potential (Vo) - the spatial average of these voltages. Voltages are very sensitive to the distribution of electrons and provide metrics to understand interactions in condensed phases. In the present study, we find excellent agreement with measurements of Vo for vitrified water and salt crystals and demonstrate the impact of covalent and ionic bonding as well as intermolecular/atomic interactions. Furthermore, we predict Vo as well as the fluctuations of these voltages in aqueous NaCl electrolytes and characterize the changes in their behavior as the resolution increases below the size of atoms. This work was supported by the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences & Biosciences. Pacific Northwest National Laboratory (PNNL) is a multiprogram national laboratory operated for DOE by Battelle. This research used resources of the National Energy Research Scientific Computing Center, which is supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.

  17. Development of a method of measuring relative phase difference between sending and receiving voltage on a power line

    E-Print Network [OSTI]

    Rackley, Benton Tiburce

    1950-01-01T23:59:59.000Z

    Westinghouse Phase Angle Meter . . . 10 6. Schematic of a Standard Phase Angle Meter . 17 7. Schematic of Converted Phase Angle Meter . . 18 8. Meter As Normally Connected To Power Line . 20 9 . Laboratory Circuit 10. Laboratorv Set Up 21 22 11. 9raph... conditions on the important lines. The attendant could then know when given lines are approaching instability and precautions could be taken on loading. BIBLIOGRAPHY BOOKS 1. Westinghouse Electric and Manufacturing Company, Electrical Transmission...

  18. Dynamic Voltage Regulation Using Distributed Energy Resources

    SciTech Connect (OSTI)

    Xu, Yan [ORNL; Rizy, D Tom [ORNL; Li, Fangxing [ORNL; Kueck, John D [ORNL

    2007-01-01T23:59:59.000Z

    Many distributed energy resources (DE) are near load centres and equipped with power electronics converters to interface with the grid, therefore it is feasible for DE to provide ancillary services such as voltage regulation, nonactive power compensation, and power factor correction. A synchronous condenser and a microturbine with an inverter interface are implemented in parallel in a distribution system to regulate the local voltage. Voltage control schemes of the inverter and the synchronous condenser are developed. The experimental results show that both the inverter and the synchronous condenser can regulate the local voltage instantaneously, while the dynamic response of the inverter is faster than the synchronous condenser; and that integrated voltage regulation (multiple DE perform voltage regulation) can increase the voltage regulation capability, increase the lifetime of the equipment, and reduce the capital and operation costs.

  19. Electric field and losses at AC self field mode in MF composites

    SciTech Connect (OSTI)

    Fukui, S.; Hlasnik, I.; Tsukamoto, O.; Amemiya, N. (Yokohama National Univ. (Japan)); Polak, M.; Kottman, P. (Slovak Academy of Science, Bratislava (Slovakia). Inst. of Electrical Engineering)

    1994-07-01T23:59:59.000Z

    Studies of the current-voltage characteristics of typical superconducting wires under static and dynamic conditions up to 50 Hz frequency have revealed much higher instantaneous local loss power densities in an external DC magnetic field than those which occur by magnetization in a transverse AC magnetic field. In this paper, the measured loss characteristics are compared with theoretical ones derived from the critical state model, and the self field AC loss are also estimated. Possible errors that can result by applying the critical state model are discussed.

  20. Multimode power processor

    DOE Patents [OSTI]

    O'Sullivan, George A. (Pottersville, NJ); O'Sullivan, Joseph A. (St. Louis, MO)

    1999-01-01T23:59:59.000Z

    In one embodiment, a power processor which operates in three modes: an inverter mode wherein power is delivered from a battery to an AC power grid or load; a battery charger mode wherein the battery is charged by a generator; and a parallel mode wherein the generator supplies power to the AC power grid or load in parallel with the battery. In the parallel mode, the system adapts to arbitrary non-linear loads. The power processor may operate on a per-phase basis wherein the load may be synthetically transferred from one phase to another by way of a bumpless transfer which causes no interruption of power to the load when transferring energy sources. Voltage transients and frequency transients delivered to the load when switching between the generator and battery sources are minimized, thereby providing an uninterruptible power supply. The power processor may be used as part of a hybrid electrical power source system which may contain, in one embodiment, a photovoltaic array, diesel engine, and battery power sources.

  1. Multimode power processor

    DOE Patents [OSTI]

    O'Sullivan, G.A.; O'Sullivan, J.A.

    1999-07-27T23:59:59.000Z

    In one embodiment, a power processor which operates in three modes: an inverter mode wherein power is delivered from a battery to an AC power grid or load; a battery charger mode wherein the battery is charged by a generator; and a parallel mode wherein the generator supplies power to the AC power grid or load in parallel with the battery. In the parallel mode, the system adapts to arbitrary non-linear loads. The power processor may operate on a per-phase basis wherein the load may be synthetically transferred from one phase to another by way of a bumpless transfer which causes no interruption of power to the load when transferring energy sources. Voltage transients and frequency transients delivered to the load when switching between the generator and battery sources are minimized, thereby providing an uninterruptible power supply. The power processor may be used as part of a hybrid electrical power source system which may contain, in one embodiment, a photovoltaic array, diesel engine, and battery power sources. 31 figs.

  2. KALRA AND LYSECKY: ASHOUEI et al.: CARLONI et al.: LIU et al.: AN APPROACH FOR ADAPTIVE DRAM TEMPERATURE AND POWER MANAGEMENT 679 [8] P. Pant, R. K. Roy, and A. Chatterjee, "Dual-threshold voltage assign-

    E-Print Network [OSTI]

    Carloni, Luca

    TEMPERATURE AND POWER MANAGEMENT 679 [8] P. Pant, R. K. Roy, and A. Chatterjee, "Dual-threshold voltage assign, and K. Roy, "Novel sizing algorithm for yield improvement under process variation in nanometer. Narendra, S. Borkar, C. Hawkins, K. Roy, and V. De, "Technology scaling of optimum reverse body bias

  3. ac traction drives: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Solid State Transformer Engineering Websites Summary: converters as distribution transformers 1. A power electronics-based solid state transformer (SST) providesAc-Ac Dual...

  4. AbstractDifferent control aspects related to the use of TCSC for stability improvement of power systems are addressed in this

    E-Print Network [OSTI]

    Cańizares, Claudio A.

    of using Flexible AC Transmission system (FACTS) controllers for enhancing power system stability are well1 AbstractDifferent control aspects related to the use of TCSC for stability improvement of power high voltage interconnected system is used to illustrate the ideas presented in the paper. Index TermsStability

  5. A Tariff for Reactive Power

    SciTech Connect (OSTI)

    Kueck, John D [ORNL; Kirby, Brendan J [ORNL; Li, Fangxing [ORNL; Tufon, Christopher [Pacific Gas and Electric Company; Isemonger, Alan [California Independent System Operator

    2008-07-01T23:59:59.000Z

    Two kinds of power are required to operate an electric power system: real power, measured in watts, and reactive power, measured in volt-amperes reactive or VARs. Reactive power supply is one of a class of power system reliability services collectively known as ancillary services, and is essential for the reliable operation of the bulk power system. Reactive power flows when current leads or lags behind voltage. Typically, the current in a distribution system lags behind voltage because of inductive loads such as motors. Reactive power flow wastes energy and capacity and causes voltage droop. To correct lagging power flow, leading reactive power (current leading voltage) is supplied to bring the current into phase with voltage. When the current is in phase with voltage, there is a reduction in system losses, an increase in system capacity, and a rise in voltage. Reactive power can be supplied from either static or dynamic VAR sources. Static sources are typically transmission and distribution equipment, such as capacitors at substations, and their cost has historically been included in the revenue requirement of the transmission operator (TO), and recovered through cost-of-service rates. By contrast, dynamic sources are typically generators capable of producing variable levels of reactive power by automatically controlling the generator to regulate voltage. Transmission system devices such as synchronous condensers can also provide dynamic reactive power. A class of solid state devices (called flexible AC transmission system devices or FACTs) can provide dynamic reactive power. One specific device has the unfortunate name of static VAR compensator (SVC), where 'static' refers to the solid state nature of the device (it does not include rotating equipment) and not to the production of static reactive power. Dynamic sources at the distribution level, while more costly would be very useful in helping to regulate local voltage. Local voltage regulation would reduce system losses, increase circuit capacity, increase reliability, and improve efficiency. Reactive power is theoretically available from any inverter-based equipment such as photovoltaic (PV) systems, fuel cells, microturbines, and adjustable-speed drives. However, the installation is usually only economical if reactive power supply is considered during the design and construction phase. In this report, we find that if the inverters of PV systems or the generators of combined heat and power (CHP) systems were designed with capability to supply dynamic reactive power, they could do this quite economically. In fact, on an annualized basis, these inverters and generators may be able to supply dynamic reactive power for about $5 or $6 per kVAR. The savings from the local supply of dynamic reactive power would be in reduced losses, increased capacity, and decreased transmission congestion. The net savings are estimated to be about $7 per kVAR on an annualized basis for a hypothetical circuit. Thus the distribution company could economically purchase a dynamic reactive power service from customers for perhaps $6/kVAR. This practice would provide for better voltage regulation in the distribution system and would provide an alternate revenue source to help amortize the cost of PV and CHP installations. As distribution and transmission systems are operated under rising levels of stress, the value of local dynamic reactive supply is expected to grow. Also, large power inverters, in the range of 500 kW to 1 MW, are expected to decrease in cost as they become mass produced. This report provides one data point which shows that the local supply of dynamic reactive power is marginally profitable at present for a hypothetical circuit. We expect that the trends of growing power flow on the existing system and mass production of inverters for distributed energy devices will make the dynamic supply of reactive power from customers an integral component of economical and reliable system operation in the future.

  6. Dynamic simulation of voltage collapses

    SciTech Connect (OSTI)

    Deuse, J.; Stubbe, M. (Tractebel, Brussels (Belgium))

    1993-08-01T23:59:59.000Z

    Most of the time the voltage collapse phenomena are studied by means of computer programs designed for the calculation of steady state conditions. But in the real world, the simultaneous occurrences of losses of synchronism, of AVR dynamics or of transformer tap changes call for a full dynamic simulation of voltage phenomena. The present paper shows some examples of dynamic simulations of voltage phenomena using a new general purpose stability program (EUROSTAG), covering in a continuous way the classical fields of transient, mid-term and long-term stability, and also the quasi steady state conditions of a power system.

  7. Power Factor Reactive Power

    E-Print Network [OSTI]

    motor power: 117.7 V x 5.1 A = 600 W? = 0.6 kW? NOT the power measured by meter #12;Page 9 PSERC: displacement power factor: angle between voltage and current = 0 degrees pf = cos(0 degrees) = 1.0 true powerPage 1 PSERC Power Factor and Reactive Power Ward Jewell Wichita State University Power Systems

  8. Non-contact current and voltage sensor

    DOE Patents [OSTI]

    Carpenter, Gary D; El-Essawy, Wael; Ferreira, Alexandre Peixoto; Keller, Thomas Walter; Rubio, Juan C; Schappert, Michael A

    2014-03-25T23:59:59.000Z

    A detachable current and voltage sensor provides an isolated and convenient device to measure current passing through a conductor such as an AC branch circuit wire, as well as providing an indication of an electrostatic potential on the wire, which can be used to indicate the phase of the voltage on the wire, and optionally a magnitude of the voltage. The device includes a housing that contains the current and voltage sensors, which may be a ferrite cylinder with a hall effect sensor disposed in a gap along the circumference to measure current, or alternative a winding provided through the cylinder along its axis and a capacitive plate or wire disposed adjacent to, or within, the ferrite cylinder to provide the indication of the voltage.

  9. Electrical system architecture having high voltage bus

    DOE Patents [OSTI]

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

    2011-03-22T23:59:59.000Z

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

  10. Distributed Voltage and Current Control of Multi-Terminal High-Voltage Direct

    E-Print Network [OSTI]

    Dimarogonas, Dimos

    }@kth.se.) Abstract: High-voltage direct current (HVDC) is a commonly used technology for long-distance power for multi-terminal HVDC (MTDC) systems is proposed. Under certain conditions on the controller gains factor behind long-distance power transmission. High-voltage direct current (HVDC) is a commonly used

  11. Abstract--The increase in use of power electronics in transmission and distribution applications is the driving

    E-Print Network [OSTI]

    Tolbert, Leon M.

    is the driving force for development of high power devices. Utility applications like FACTS and HVDC require cost and compared for SiC and Si devices. These loss models are integrated with an HVDC transmission system to study of the systems. High Voltage DC (HVDC) transmission and Flexible AC Transmission Systems (FACTS) are the widely

  12. Reactive Support and Voltage Control Service: Key Issues and Challenges

    E-Print Network [OSTI]

    Gross, George

    reactive support and voltage control services. Keywords ­ Competitive Electricity Markets, Reactive PowerReactive Support and Voltage Control Service: Key Issues and Challenges George Gross^, Paolo Marannino° and Gianfranco Chicco* ^ Department of Electrical and Computer Engineering, University

  13. AC Resistance measuring instrument

    DOE Patents [OSTI]

    Hof, Peter J. (Richland, WA)

    1983-01-01T23:59:59.000Z

    An auto-ranging AC resistance measuring instrument for remote measurement of the resistance of an electrical device or circuit connected to the instrument includes a signal generator which generates an AC excitation signal for application to a load, including the device and the transmission line, a monitoring circuit which provides a digitally encoded signal representing the voltage across the load, and a microprocessor which operates under program control to provide an auto-ranging function by which range resistance is connected in circuit with the load to limit the load voltage to an acceptable range for the instrument, and an auto-compensating function by which compensating capacitance is connected in shunt with the range resistance to compensate for the effects of line capacitance. After the auto-ranging and auto-compensation functions are complete, the microprocessor calculates the resistance of the load from the selected range resistance, the excitation signal, and the load voltage signal, and displays of the measured resistance on a digital display of the instrument.

  14. AC resistance measuring instrument

    DOE Patents [OSTI]

    Hof, P.J.

    1983-10-04T23:59:59.000Z

    An auto-ranging AC resistance measuring instrument for remote measurement of the resistance of an electrical device or circuit connected to the instrument includes a signal generator which generates an AC excitation signal for application to a load, including the device and the transmission line, a monitoring circuit which provides a digitally encoded signal representing the voltage across the load, and a microprocessor which operates under program control to provide an auto-ranging function by which range resistance is connected in circuit with the load to limit the load voltage to an acceptable range for the instrument, and an auto-compensating function by which compensating capacitance is connected in shunt with the range resistance to compensate for the effects of line capacitance. After the auto-ranging and auto-compensation functions are complete, the microprocessor calculates the resistance of the load from the selected range resistance, the excitation signal, and the load voltage signal, and displays of the measured resistance on a digital display of the instrument. 8 figs.

  15. Application of GTO voltage source inverter in a hybrid HVDC link

    SciTech Connect (OSTI)

    Zhao, Z.; Iravani, M.R. (Univ. of Toronto, Ontario (Canada). Dept. of Electrical Engineering)

    1994-01-01T23:59:59.000Z

    This paper investigates the application of a GTO voltage source inverter in a two-terminal HVdc link, which is fed at the sending end by a line-commutated rectifier. This type of HVdc link may be applied when power transfer is predominantly unidirectional, especially to a weak ac system. The investigations are based on analytical studies and digital time-domain simulations with the Electro-Magnetic Transient program for DC systems (EMTDC). Control method and protection requirements are studied, together with dynamic behavior of the system following disturbances, e.g. dc fault, ac fault, start-up etc. The studies are aimed at exhibiting the technical feasibility of the proposed HVdc scheme. Need for further studies is pointed out when necessary.

  16. english 31AC african-amercan studies 17AC history 7B public health 130AC sociology 3AC education 30AC ethnic studies 135AC geography 150AC history 127AC information 142AC psychology 125AC anthropology 2AC american

    E-Print Network [OSTI]

    Alvarez-Cohen, Lisa

    · anthropology 2AC · american studies 10AC · gender and womens studies 50AC · music 26AC · spanish 135AC 50AC · music 26AC · spanish 135AC · sociology 190AC · public policy 117AC · peace and conflict studies 10AC · gender and womens studies 50AC · music 26AC · spanish 135AC · sociology 190AC · public

  17. IEEE International Conference on Power and Energy (PECon 08), December 1-3, 2008, Johor Baharu, Malaysia Variable High Frequency Voltage Source for an

    E-Print Network [OSTI]

    Hammerton, James

    , Malaysia Variable High Frequency Voltage Source for an Ohmic Heating Process A. Toudeshki, N. Mariun SMIEEE: arashtoudeshki@gmail.com Abstract-- Heating is an important step in food processing. A new method of heating uses the natural electrical resistance of the food to generate heat. In this method electrical energy

  18. Corona and Motor Voltage Interim Report

    SciTech Connect (OSTI)

    Hsu, J.S.

    2005-05-06T23:59:59.000Z

    It has been suggested that to meet the FreedomCAR objectives for cost, size, weight, efficiency, and reliability higher buss voltages be utilized in HEV and FC automotive applications. The reasoning is that since electric power is equal to the product of voltage and current for a given power a higher voltage and lower current would result in smaller cable and inverter switching components. Consequently, the system can be lighter and smaller. On the other hand, higher voltages are known to require better and thicker electrical insulation that reduce the available slot area for motor windings. One cause of slow insulation breakdown is corona that gradually erodes the insulation and shortens the life expectancy of the motor. This study reports on the results of a study on corona initiating voltages for mush-wound and bobbin-wound stators. A unique testing method is illustrated.

  19. Voltage instability: Mechanisms and control strategies

    SciTech Connect (OSTI)

    Vu, K.T. [ABB Transmission Technology Inst., Raleigh, NC (United States). Power Systems Center] [ABB Transmission Technology Inst., Raleigh, NC (United States). Power Systems Center; Liu, C.C. [Univ. of Washington, Seattle, WA (United States)] [Univ. of Washington, Seattle, WA (United States); Taylor, C.W. [Bonneville Power Administration, Portland, OR (United States)] [Bonneville Power Administration, Portland, OR (United States); Jimma, K.M. [Puget Sound Power and Light Co., Bellevue, WA (United States)] [Puget Sound Power and Light Co., Bellevue, WA (United States)

    1995-11-01T23:59:59.000Z

    One of the main objectives in operating an electric power system is to maintain a proper voltage level throughout a system. Failure to do so can lead to equipment damage and blackout. The article discusses the nonlinear aspects of power systems, with emphasis on voltage instability. It provides an overview of the state-of-the-art on the analysis and control of voltage dynamics. Dynamic mechanisms and control strategies are discussed from both theoretical and practical standpoints. The remedial controls implemented in the Puget Sound region of the Pacific Northwest indicate the practical significance of the research area.

  20. Experimental and theoretical studies of a high temperature cesium-barium tacitron, with application to low voltage-high current inversion. Final report, April 1, 1993--February 28, 1994

    SciTech Connect (OSTI)

    Murray, C.S.; El-Genk, M.S.

    1994-02-01T23:59:59.000Z

    A low voltage/high current switch refer-red as ``Cs-Ba tacitron`` is studied for use as a dc to ac inverter in high temperature and/or ionizing radiation environments. The operational characteristics of the Cs-Ba tacitron as a switch were investigated experimentally in three modes: (a) breakdown mode, (b) I-V mode, and (c) current modulation mode. Operation parameters measured include switching frequencies up to 20 kHz, hold-off voltages up to 200 V, current densities in excess of 15 A/CM{sup 2}, switch power density of 1 kW/cm{sup 2}, and a switching efficiency in excess of 90 % at collector voltages greater than 30 V. Also, if the discharge current is circuit limited to a value below the maximum thermal emission current density, the voltage drop is constant and below 3 V.

  1. Techniques for energy conservation in ac motor-driven systems. Final report

    SciTech Connect (OSTI)

    Mohan, N.

    1981-09-01T23:59:59.000Z

    Techniques for energy conservation of reducing losses in ac motor-driven systems proposed by the technical community in response to surging cost of energy are evaluated and compared. Report objectives are to provide better understanding of underlying principles and to evaluate technical and economic viability of these techniques for various applications. An important aspect considered is the impact on electric utility system in terms of harmonics, power factor of operation, and Electro-Magnetic Interference (EMI). The techniques evaluated are: NASA Power Factor Controller, a simple device for reducing power losses in lightly loaded ac motors; wanlass motor modification, a scheme of reconnecting motor windings with capacitors in series, with the intention of improving the motor efficiencies under all loading conditions; conventional variable frequency solid-state inverters which can control the speed of ac motors by producing adjustable frequency ac voltage, with a significant potential for energy conservation in pumps and air-handling systems; and other variable frequency drives and schemes including cycloconverters, slip-recovery scheme, Exxon Alternating Current Synthesizer, Venturini conversion technique, permanent magnet synchronous motors, and a device called the Phase-Liner. The impact of rapid growth in semiconductors and magnetic materials technologies is also considered.

  2. High Voltage Safety Act

    Broader source: Energy.gov [DOE]

    The purpose of the High Voltage Safety Act is to prevent injury to persons and property and interruptions of utility service resulting from accidental or inadvertent contact with high-voltage...

  3. Simplified VO M&V Protocol Simplified Voltage Optimization (VO)

    E-Print Network [OSTI]

    of all distribution lines that are controlled by a tap changing source voltage regulator. Several voltage-control primary system with source voltage regulation. Minimum system stability thresholds, system data modeling is mentioned, it refers to using industry accepted distribution system power flow simulation tools

  4. Distribution System Voltage Regulation by Distributed Energy Resources

    SciTech Connect (OSTI)

    Ceylan, Oguzhan [ORNL; Liu, Guodong [ORNL; Xu, Yan [ORNL; Tomsovic, Kevin [University of Tennessee, Knoxville (UTK)

    2014-01-01T23:59:59.000Z

    This paper proposes a control method to regulate voltages in 3 phase unbalanced electrical distribution systems. A constrained optimization problem to minimize voltage deviations and maximize distributed energy resource (DER) active power output is solved by harmony search algorithm. IEEE 13 Bus Distribution Test System was modified to test three different cases: a) only voltage regulator controlled system b) only DER controlled system and c) both voltage regulator and DER controlled system. The simulation results show that systems with both voltage regulators and DER control provide better voltage profile.

  5. A High Frequency Isolated Current-fed Bidirectional DC/AC Converter For Grid-Tied Energy Storage System

    E-Print Network [OSTI]

    King Jet, TSENG

    2013-01-01T23:59:59.000Z

    tied energy storage systems (ESS) will be voltage to a high-DC/AC converter to interface ESS based on low voltage cellscharging and discharging of the ESS and the control strategy

  6. Booster main magnet power supply, present operation and potential future upgrades

    SciTech Connect (OSTI)

    Bajon, E.; Bannon, M.; Marneris, I.; Danowski, G.; Sandberg, J.; Savatteri, S.

    2011-03-28T23:59:59.000Z

    The Brookhaven Booster Main Magnet Power Supply (MMPS) is a 24 pulse thyristor control supply, rated at 5500 Amps, +/-2000 Volts, or 3000 Amps, +/-6000 Volts. The power supply is fed directly from the power utility and the peak magnet power is 18 MWatts. This peak power is seen directly at the incoming ac line. This power supply has been in operation for the last 18 years. This paper will describe the present topology and operation of the power supply, the feedback control system and the different modes of operation of the power supply. Since the power supply has been in operation for the last 18 years, upgrading this power supply is essential. A new power supply topology has been studied where energy is stored in capacitor banks. DC to DC converters are used to convert the dc voltage stored in the capacitor banks to pulsed DC voltage into the magnet load. This enables the average incoming power from the ac line to be constant while the peak magnet power is pulsed to +/- 18 MWatts. Simulations and waveforms of this power supply will be presented.

  7. Triple voltage dc-to-dc converter and method

    DOE Patents [OSTI]

    Su, Gui-Jia (Knoxville, TN)

    2008-08-05T23:59:59.000Z

    A circuit and method of providing three dc voltage buses and transforming power between a low voltage dc converter and a high voltage dc converter, by coupling a primary dc power circuit and a secondary dc power circuit through an isolation transformer; providing the gating signals to power semiconductor switches in the primary and secondary circuits to control power flow between the primary and secondary circuits and by controlling a phase shift between the primary voltage and the secondary voltage. The primary dc power circuit and the secondary dc power circuit each further comprising at least two tank capacitances arranged in series as a tank leg, at least two resonant switching devices arranged in series with each other and arranged in parallel with the tank leg, and at least one voltage source arranged in parallel with the tank leg and the resonant switching devices, said resonant switching devices including power semiconductor switches that are operated by gating signals. Additional embodiments having a center-tapped battery on the low voltage side and a plurality of modules on both the low voltage side and the high voltage side are also disclosed for the purpose of reducing ripple current and for reducing the size of the components.

  8. High voltage dc--dc converter with dynamic voltage regulation and decoupling during load-generated arcs

    DOE Patents [OSTI]

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

    1995-05-23T23:59:59.000Z

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

  9. High voltage dc-dc converter with dynamic voltage regulation and decoupling during load-generated arcs

    DOE Patents [OSTI]

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

    1995-01-01T23:59:59.000Z

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

  10. A new high performance AC to DC rectifier with input power factor correction and harmonic reduction capacity

    E-Print Network [OSTI]

    Martinez, Roberto

    1994-01-01T23:59:59.000Z

    ]. Unfortunately, the maximum power factor that could be achieved is 0. 763. 0, 9 o. e E 0. 7 ll 0. 6 0. 5 m=0. 79 PF = 0. 763 Disixnt. Mtxte I 8 'o + o 0 0 CI PF Contirucus Mcci III 0, 4 Pn = 0. 052 0. 0001 0, 001 0. 01 0. 1 1 10 100 Pn Fig...

  11. Panel Session: Optimization Techniques in Voltage Collapse Analysis," IEEE PES Summer Meeting, San Diego, July 14, 1998. Applications of Optimization to Voltage Collapse Analysis

    E-Print Network [OSTI]

    Cañizares, Claudio A.

    Panel Session: Optimization Techniques in Voltage Collapse Analysis," IEEE PES Summer Meeting, San Diego, July 14, 1998. Applications of Optimization to Voltage Collapse Analysis Claudio A. Ca|Thispaper describesseveralapplica- tions of optimization for voltage stability analysis VSA of power systems. Voltage stability prob

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

    DOE Patents [OSTI]

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

    2013-02-26T23:59:59.000Z

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

  13. Multilevel Cascade H-bridge Inverter DC Voltage Estimation Through Output Voltage Sensing

    E-Print Network [OSTI]

    Tolbert, Leon M.

    system as the inverter power supply may vary. For example, interface of solar panels or fuel cell. The output voltage is then processed by a DSP unit that uses the signals that command the switches

  14. October 6, 2006 V. Ghazikhanian 1 TOF Low Voltage System Review

    E-Print Network [OSTI]

    Llope, William J.

    TOF Low Voltage Power System. The TOF low voltage system is based on the Wiener PL512 low noise, high45 plugs #12;October 6, 2006 V. Ghazikhanian Tray Low Voltage Power System. Totalof120 the plot of the dark current data on slide]. The DC power will be transmitted via DC transmission lines

  15. Group 3: Humidity, Temperature, and Voltage

    Broader source: Energy.gov [DOE]

    This PowerPoint presentation, focused on humidity, temperature and voltage testing, was originally presented by John Wohlgemuth at the NREL 2013 PV Module Reliability Workshop on Feb. 26-27, 2013 in Denver, CO. It summarizes the activities of a working group chartered to develop accelerated stress tests that can be used as comparative predictors of module life versus stresses associated with humidity, temperature and voltage.

  16. Optical voltage reference

    DOE Patents [OSTI]

    Rankin, R.; Kotter, D.

    1994-04-26T23:59:59.000Z

    An optical voltage reference for providing an alternative to a battery source is described. The optical reference apparatus provides a temperature stable, high precision, isolated voltage reference through the use of optical isolation techniques to eliminate current and impedance coupling errors. Pulse rate frequency modulation is employed to eliminate errors in the optical transmission link while phase-lock feedback is employed to stabilize the frequency to voltage transfer function. 2 figures.

  17. High Voltage DC Transmission 2 1.0 Introduction

    E-Print Network [OSTI]

    McCalley, James D.

    1 High Voltage DC Transmission 2 1.0 Introduction Interconnecting HVDC within an AC system requires on use of switching devices collectively referred to in the HVDC community as valves. Valves may be non. Fig. 1 There have been three types of devices for implementing HVDC converter circuits: mercury

  18. Power Right. Power Smart. Efficient Computer Power Supplies and...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AC power that you get from your electric company into the DC power consumed by most electronics, including your computer. We expect our power supplies to be safe, reliable, and...

  19. IEEE Transactions on Power Delivery, Vol. 11, No. 1, January 1996 SF6 Dielectric Behaviour in a High Voltage Circuit Breaker

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    IEEE Transactions on Power Delivery, Vol. 11, No. 1, January 1996 SF6 Dielectric Behaviour. and d =39.6 kg/m3. Devices allowing to detect the appearance of local condensa- tion of SF6 of SF6 due to a temperature effect, even without condensation, could have great importance in the design

  20. A low-voltage zero-crossing-based delta-sigma analog-to-digital converter

    E-Print Network [OSTI]

    Guyton, Matthew C. (Matthew Christopher)

    2010-01-01T23:59:59.000Z

    A zero-crossing-based (ZCB) switched-capacitor technique is presented for operation under low power supply voltages without gate boosting. Voltage ramp generators maintain common-mode level at each integrator output. ...

  1. Time varying voltage combustion control and diagnostics sensor

    DOE Patents [OSTI]

    Chorpening, Benjamin T. (Morgantown, WV); Thornton, Jimmy D. (Morgantown, WV); Huckaby, E. David (Morgantown, WV); Fincham, William (Fairmont, WV)

    2011-04-19T23:59:59.000Z

    A time-varying voltage is applied to an electrode, or a pair of electrodes, of a sensor installed in a fuel nozzle disposed adjacent the combustion zone of a continuous combustion system, such as of the gas turbine engine type. The time-varying voltage induces a time-varying current in the flame which is measured and used to determine flame capacitance using AC electrical circuit analysis. Flame capacitance is used to accurately determine the position of the flame from the sensor and the fuel/air ratio. The fuel and/or air flow rate (s) is/are then adjusted to provide reduced flame instability problems such as flashback, combustion dynamics and lean blowout, as well as reduced emissions. The time-varying voltage may be an alternating voltage and the time-varying current may be an alternating current.

  2. AUV {gslee, sbahk}@netlab.snu.ac.kr

    E-Print Network [OSTI]

    Bahk, Saewoong

    AUV , {gslee, sbahk}@netlab.snu.ac.kr Transmission Power Control in Cluster AUV (CH) AUV . 1 . 1. 2. 3 . AUV CH (Buoy

  3. ac conductivity studies: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Last updated 8 Plotkin, Joshua B. 40 Study of supplementary controls for embedded HVDC links in a AC power system. Open Access Theses and Dissertations Summary: ??This...

  4. ac line conditioners: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of lines . ..2 Main Terasoma, Tomohide 83 Study of supplementary controls for embedded HVDC links in a AC power system. Open Access Theses and Dissertations Summary: ??This...

  5. TCSC as a Transient Voltage Stabilizing Controller Garng Huang and Tong Zhu

    E-Print Network [OSTI]

    to enhance the voltage stability by changing the reactive power distribution in the power system. Authors and operated by some utilities [1,2]. The primary uses of TCSC are to enhance the power system angle stability on the small signal voltage stability for a simple power system with an infinitive bus and a dynamic load

  6. ABBGroup-1-High voltage lab

    E-Print Network [OSTI]

    Basse, Nils Plesner

    oscillations are due to travelling waves in the heating volume. #12;©ABBGroup-9- 3-Sep-07 2. High voltage phase interrupts the injected current, it is stressed by the transient recovery voltage (TRV) oscillating©ABBGroup-1- 3-Sep-07 High voltage lab Research on high voltage gas circuit breakers Nils P. Basse

  7. Electronic power conditioning for dynamic power conversion in high-power space systems

    E-Print Network [OSTI]

    Hansen, James Michael

    1991-01-01T23:59:59.000Z

    . 55. 56. 57. Voltage and Current Waveforms for the Single-Phase PM System at Full Power ? w = v, z, z . Voltage and Current Waveforms f' or the Single-Phase PiVI System at Full Power ? ~ & cu, q, s, Compensated Voltage and Current Waveforms..., Compensated Voltage and Current Waveforms for the Single-Phase PM System at Half Power ? ~ & ~?, z, s, Compensated Voltage and Current Waveforms for the Three-Phase WF System at Full Power ? w: M, gtpd Voltage and Current Waveforms for the Three-Phase WF...

  8. Chapter 24: Alternating-Current Circuits 2. The voltage in the European wall socket oscillates between the positive and negative peak voltages, resulting in an rms

    E-Print Network [OSTI]

    Kioussis, Nicholas

    1 Chapter 24: Alternating-Current Circuits 2. The voltage in the European wall socket oscillates 240 V 340 VV V 6. A light bulb dissipates power as the voltage oscillates across its filament.0 V 1.32 A 15.2 V I X 13. An oscillating voltage drives an alternating current through a capacitor

  9. Electron launching voltage monitor

    DOE Patents [OSTI]

    Mendel, C.W.; Savage, M.E.

    1992-03-17T23:59:59.000Z

    An electron launching voltage monitor measures MITL voltage using a relationship between anode electric field and electron current launched from a cathode-mounted perturbation. An electron launching probe extends through and is spaced from the edge of an opening in a first MITL conductor, one end of the launching probe being in the gap between the MITL conductor, the other end being adjacent a first side of the first conductor away from the second conductor. A housing surrounds the launching probe and electrically connects the first side of the first conductor to the other end of the launching probe. A detector detects the current passing through the housing to the launching probe, the detected current being representative of the voltage between the conductors. 5 figs.

  10. Electronic high voltage generator with a high temperature superconducting coil

    SciTech Connect (OSTI)

    Jin, J.X.; Liu, H.K.; Dou, S.X. [Univ. of Wollongong (Australia)] [and others

    1996-12-31T23:59:59.000Z

    A novel method for generating high voltages from a low voltage DC source, by using a capacitor and inductor in a R, L, C resonant circuit has been developed with the consideration of using a high temperature superconducting (HTS) coil. To generate high voltages the polarity of a low voltage battery source is reversed each half resonant cycle, the control being achieved by an electronic switch. Resistance in the circuit limits the voltages that can be built up. By replacing a copper winding inductor with another inductor which has a HTS winding, the magnitude of achievable voltages is substantially increased. A (Bi,Pb){sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub 10+x} multifilament HTS wire is considered in this work to make the superconducting inductor. The high voltages generated are not capable of supplying low impedance loads, however, possible applications of the generator include electrical partial discharge testing and insulation resistance testing. It could also be used as a testing method for the HTS itself with respect to the critical current and AC loss measurement.

  11. Threshold voltage extraction circuit

    E-Print Network [OSTI]

    Hoon, Siew Kuok

    2000-01-01T23:59:59.000Z

    to that of the saturation method. However, instead of fixing Vos ? Vos, the drain current is measured as a function of Vos while Vns is fixed at a constant low voltage of 100mV to ensure operation in the linear MOSFET region. Neglecting channel length modulation effect... transistors are layout next to the DUT of the NMOS and PMOS Vr extraction circuits respectively for extraction of Vr via graphical means. GRAPHICAL METHOD OF THE THRESHOLD-VOLTAGE MEASUREMENT Using the graphical method, the characteristics of 4n versus Vos...

  12. Rotating electrical machines - Part 22: AC generators for reciprocating internal combustion (RIC) engine driven generating sets

    E-Print Network [OSTI]

    International Electrotechnical Commission. Geneva

    1996-01-01T23:59:59.000Z

    Establishes the principal characteristics of a.c. generators under the control of their voltage regulators when used for reciprocating internal combustion engine driven generating sets. Supplements the requirements given in IEC 60034-1.

  13. Reactive Power Compensation Technologies, State-of-the-Art Review

    E-Print Network [OSTI]

    Catholic University of Chile (Universidad CatĂłlica de Chile)

    at all levels of power transmission, it improves HVDC (High Voltage Direct Current) conversion terminal

  14. IMPACT OF DYNAMIC VOLTAGE SCALING (DVS) ON CIRCUIT OPTIMIZATION

    E-Print Network [OSTI]

    Esquit Hernandez, Carlos A.

    2010-01-16T23:59:59.000Z

    Circuit designers perform optimization procedures targeting speed and power during the design of a circuit. Gate sizing can be applied to optimize for speed, while Dual-VT and Dynamic Voltage Scaling (DVS) can be applied to optimize for leakage...

  15. IMPACT OF DYNAMIC VOLTAGE SCALING (DVS) ON CIRCUIT OPTIMIZATION 

    E-Print Network [OSTI]

    Esquit Hernandez, Carlos A.

    2010-01-16T23:59:59.000Z

    Circuit designers perform optimization procedures targeting speed and power during the design of a circuit. Gate sizing can be applied to optimize for speed, while Dual-VT and Dynamic Voltage Scaling (DVS) can be applied ...

  16. Power Factor Compensation (PFC) Power Factor Compensation

    E-Print Network [OSTI]

    Knobloch,JĂĽrgen

    Power Factor Compensation (PFC) Power Factor Compensation The power factor (PF) is defined as the ratio between the active power and the apparent power of a system. If the current and voltage are periodic with period , and [ ), then the active power is defined by ( ) ( ) (their inner product

  17. DECENTRALIZED CONTROL ARCHITECTURE FOR COUPLING MICROGRIDS INTO DISTRIBUTION NETWORKS 1 Task 1: Coupling Low-Voltage Microgrids into

    E-Print Network [OSTI]

    Lemmon, Michael

    DECENTRALIZED CONTROL ARCHITECTURE FOR COUPLING MICROGRIDS INTO DISTRIBUTION NETWORKS 1 Task 1: Coupling Low-Voltage Microgrids into Mid-Voltage Distribution Systems Zhao Wang, Student Member, IEEE-voltage (LV) microgrids. At the same time, reactive power is dispatched coordinatively so that voltage

  18. Smart Grid Voltage Sag Detection using Instantaneous Features Extraction

    E-Print Network [OSTI]

    Boyer, Edmond

    encountered power quality disturbances. Index Terms--Smart grid, voltage sag detection, power quality (PQ as the generation system is moved nearby the distribution level and this is achieved by using a set of micro grids grids are their availability, reliability, and profitability; in order to fulfill power demand according

  19. Introduction What is power electronics?

    E-Print Network [OSTI]

    Knobloch,JĂĽrgen

    : single/multi-phase, full/half-bridge Applications: renewable energy, UPS, electric vehicles, HVDC. AC Rectifiers: single/multi-phase, full/half-bridge Applications: all grid powered electronic devices, HVDC. AC

  20. Figure 1. Voltage margins to manage fluctuations. AUDIT: Stress Testing the Automatic Way

    E-Print Network [OSTI]

    John, Lizy Kurian

    .govindan}@amd.com Abstract--Sudden variations in current (large di/dt) can lead to significant power supply voltage droops; stressmark generation; voltage droop; power distribution network; low power; genetic algorithm; hardware][12][13]. Other work addressed mitigating droops that occur due to various architectural events [3

  1. System and method for determining stator winding resistance in an AC motor

    DOE Patents [OSTI]

    Lu, Bin (Kenosha, WI); Habetler, Thomas G. (Snellville, GA); Zhang, Pinjia (Atlanta, GA); Theisen, Peter J. (West Bend, WI)

    2011-05-31T23:59:59.000Z

    A system and method for determining stator winding resistance in an AC motor is disclosed. The system includes a circuit having an input connectable to an AC source and an output connectable to an input terminal of an AC motor. The circuit includes at least one contactor and at least one switch to control current flow and terminal voltages in the AC motor. The system also includes a controller connected to the circuit and configured to modify a switching time of the at least one switch to create a DC component in an output of the system corresponding to an input to the AC motor and determine a stator winding resistance of the AC motor based on the injected DC component of the voltage and current.

  2. A Generalized Class of Stationary Frame-Current Controllers for Grid-Connected AC–DC Converters

    E-Print Network [OSTI]

    Hwang, J. George

    Within power systems, high-power pulsewidth-modulated ac-dc converters are used in flexible ac transmission systems controllers and for interfacing renewable energy sources to the grid. These converters traditionally ...

  3. The Centre for Power Transmission

    E-Print Network [OSTI]

    Burton, Geoffrey R.

    The Centre for Power Transmission and Motion Control Centre for PTMC Department of Mechanical) 1225 38-6371 Email: ptmc@bath.ac.uk Web: http://www.bath.ac.uk/ptmc/ Consultancy Project WAVE POWER SYSTEM SIMULATIONS Power take-off systems Wave power take-off systems are an exciting new development

  4. 1. ABSTRACT A 1.4-GHz LC voltage-controlled oscillator has

    E-Print Network [OSTI]

    Lee, Thomas H.

    1. ABSTRACT A 1.4-GHz LC voltage-controlled oscillator has been implemented in a MOSIS 0.5-µm CMOS integrated, low noise, low power voltage-controlled oscillator (VCO). For higher quality receivers, an LC the overall phase noise. In this paper, we present such an LC voltage-controlled oscillator fabricated through

  5. Hierarchical Control Scheme for Voltage Harmonics Compensation in an Islanded Droop-

    E-Print Network [OSTI]

    Vasquez, Juan Carlos

    Hierarchical Control Scheme for Voltage Harmonics Compensation in an Islanded Droop- Controlled on the resistance emulation. Furthermore, a droop characteristic based on DG harmonic reactive power has been

  6. High voltage pulse conditioning

    DOE Patents [OSTI]

    Springfield, Ray M. (Sante Fe, NM); Wheat, Jr., Robert M. (Los Alamos, NM)

    1990-01-01T23:59:59.000Z

    Apparatus for conditioning high voltage pulses from particle accelerators in order to shorten the rise times of the pulses. Flashover switches in the cathode stalk of the transmission line hold off conduction for a determinable period of time, reflecting the early portion of the pulses. Diodes upstream of the switches divert energy into the magnetic and electrostatic storage of the capacitance and inductance inherent to the transmission line until the switches close.

  7. Power dissipation characteristics of zinc-oxide arresters for HVDC systems

    SciTech Connect (OSTI)

    Horiuchi, S.; Ichikawa, F. (Tokyo Electric Power Co., Inc., Tokyo (JP)); Mizukoshi, A. (Hitachi Research Lab., Hitachi Ltd. (JP)); Kurita, K.; Shirakawa, S. (Kokubu Works Hitachi Ltd., Ibaraki (JP))

    1988-10-01T23:59:59.000Z

    Zinc-oxide arresters without series gaps have been used for HVDC systems. The voltage wave shapes applied to HVDC arresters are not a simple sinusoidal shape, so that the leakage current contains high frequency components. The power dissipation characteristics of a thyristor valve arrester were measured using a 1/25 prorated arrester section with a 5kV/500kW thyristor bridge. High frequency power dissipation characteristics of zinc-oxide elements were measured and it was shown that the high frequency power dissipation of the thyristor valve arrester was larger than that of an AC system arrester. Consideration of the equivalent continuous operating voltage for the performance test of an HVDC arrester are presented.

  8. An Adaptive Voltage Control Algorithm with Multiple Distributed Energy

    SciTech Connect (OSTI)

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

    2009-01-01T23:59:59.000Z

    Distributed energy resources (DE) with power electronics (PE) interfaces with the right control are capable of providing reactive power related ancillary services. Voltage regulation in particular has drawn much attention. In this paper the challenges to control multiple DEs to regulate the local voltage in distribution systems is addressed and a decentralized adaptive voltage control method is proposed. The simulation results in different system conditions show that this adaptive voltage control method is capable of satisfying the fast response speed requirement without causing oscillation or instability of the system. Since this method has high tolerance to the shortage of the system parameters and can be widely adaptive to the variable operation situations of the power systems, it is very suited for the utility application.

  9. Charge-pump voltage converter

    DOE Patents [OSTI]

    Brainard, John P. (Albuquerque, NM); Christenson, Todd R. (Albuquerque, NM)

    2009-11-03T23:59:59.000Z

    A charge-pump voltage converter for converting a low voltage provided by a low-voltage source to a higher voltage. Charge is inductively generated on a transfer rotor electrode during its transit past an inductor stator electrode and subsequently transferred by the rotating rotor to a collector stator electrode for storage or use. Repetition of the charge transfer process leads to a build-up of voltage on a charge-receiving device. Connection of multiple charge-pump voltage converters in series can generate higher voltages, and connection of multiple charge-pump voltage converters in parallel can generate higher currents. Microelectromechanical (MEMS) embodiments of this invention provide a small and compact high-voltage (several hundred V) voltage source starting with a few-V initial voltage source. The microscale size of many embodiments of this invention make it ideally suited for MEMS- and other micro-applications where integration of the voltage or charge source in a small package is highly desirable.

  10. INTEGRATED GHz VOLTAGE CONTROLLED OSCILLATORS

    E-Print Network [OSTI]

    Kinget, Peter

    INTEGRATED GHz VOLTAGE CONTROLLED OSCILLATORS Peter Kinget Bell Labs - Lucent Technologies Murray Hill, NJ (USA) Abstract The voltage controlled oscillator (VCO) is a critical sub. We focus on the de- sign of a critical sub-block: the voltage controlled oscillator (VCO). We review

  11. Truthful Complex-valued Knapsack Problem and Discrete Optimization in A/C Electrical Grid

    E-Print Network [OSTI]

    Chau, Chi-Kin

    2012-01-01T23:59:59.000Z

    Since efficient power allocation is a critical requirement for smart grid, we study an important basic setting -- "knapsack problem with selfish users", whereby we design a mechanism to find a utility-maximizing allocation for a group of users with inelastic demands, such that users truthfully reveal their private utility information. As a departure from the traditional setting, complex-valued entities (e.g. power, voltage, and current) are common in A/C electrical grid. There were only few results in the literature concerning complex-valued entities for discrete optimization, because they are substantially more challenging. In this paper, we introduce a non-trivial generalization of knapsack problem with a complex-valued constraint on A/C power, which casts fundamental insight to discrete optimization for smart grid. We provide results of approximability (the existence of a (1/2- e-approximation algorithm) and inapproximability (the absence of FPTAS unless P = NP) for a class of complex-valued knapsack probl...

  12. What Will Power the Hydrogen Economy? Present and Future Sources of Hydrogen Energy

    E-Print Network [OSTI]

    Kammen, Daniel M.

    Will Power the Hydrogen Economy? iii Abbreviations and Acronyms AC = alternating current ATR = autothermal

  13. High-voltage direct current handbook: First edition

    SciTech Connect (OSTI)

    Piwko, R.J.; Leonard, D.J.; Nolan, J.J.; Thorpe, J.B. [eds.] [GE Industrial and Power Systems, Schenectady, NY (United States)

    1994-12-31T23:59:59.000Z

    HVDC systems offer opportunities for power transfer between asynchronous systems, improved performance of the ac system in which the dc link is integrated, and possibly increased power transfer across existing lines if converted to HVDC. This handbook is intended to help planners and engineers understand the intricacies of HVDC systems.

  14. Development of a termination for the 77kV-class high Tc superconducting power cable

    SciTech Connect (OSTI)

    Shimonosono, T.; Nagaya, S. [Chubu Electric Power Co., Inc., Nagoya (Japan)] [Chubu Electric Power Co., Inc., Nagoya (Japan); Masuda, T.; Isojima, S. [Sumitomo Electric Industries Ltd., Osaka (Japan)] [Sumitomo Electric Industries Ltd., Osaka (Japan)

    1997-01-01T23:59:59.000Z

    A termination for 77kV-class high Tc superconducting power cables was designed and fabricated. The termination is insulated with SF6 gas, nitrogen gas and liquid nitrogen and is cooled with liquid nitrogen. The current lead has a cross sectional area altered along its axis in order to decrease the heat inlet and to prevent SF6 gas from liquefying. The current lead is insulated with Ethylene-propylene Rubber (EPR) because it passes through nitrogen gas which has low dielectric strength in comparison with liquid nitrogen and SF6 gas. 200A AC current and 70 kV AC voltage to ground were successfully applied simultaneously for 40 hours in total. The measured heat loss of the termination, 9W is in good agreement with the calculated value. As the next step, the applied voltage was increased and the termination was confirmed to withstand the voltage up to 120 kV AC and 400kV Imp to ground.

  15. Voltage control on a train system

    DOE Patents [OSTI]

    Gordon, Susanna P.; Evans, John A.

    2004-01-20T23:59:59.000Z

    The present invention provides methods for preventing low train voltages and managing interference, thereby improving the efficiency, reliability, and passenger comfort associated with commuter trains. An algorithm implementing neural network technology is used to predict low voltages before they occur. Once voltages are predicted, then multiple trains can be controlled to prevent low voltage events. Further, algorithms for managing inference are presented in the present invention. Different types of interference problems are addressed in the present invention such as "Interference During Acceleration", "Interference Near Station Stops", and "Interference During Delay Recovery." Managing such interference avoids unnecessary brake/acceleration cycles during acceleration, immediately before station stops, and after substantial delays. Algorithms are demonstrated to avoid oscillatory brake/acceleration cycles due to interference and to smooth the trajectories of closely following trains. This is achieved by maintaining sufficient following distances to avoid unnecessary braking/accelerating. These methods generate smooth train trajectories, making for a more comfortable ride, and improve train motor reliability by avoiding unnecessary mode-changes between propulsion and braking. These algorithms can also have a favorable impact on traction power system requirements and energy consumption.

  16. An Integrated Security-constrained Model-based Dynamic Power Management Approach for Isolated Microgrid Power Systems

    E-Print Network [OSTI]

    Mashayekh, Salman

    2013-11-22T23:59:59.000Z

    Prime Mover and Control GeneratorExcitation System and Control Shaft Power Field Current Voltage Speed / Power Speed Generating Unit Controls – Unit 1 Reactive Power and Voltage Control HVDC Transmission and Associated Controls System Generation...

  17. Experiment and Simulation of Dynamic Voltage Regulation in Multiple Distributed Energy Resources Systems

    SciTech Connect (OSTI)

    Xu, Yan [ORNL; Li, Fangxing [ORNL; Kueck, John D [ORNL; Rizy, D Tom [ORNL

    2007-01-01T23:59:59.000Z

    Distributed energy (DE) resources are power sources located near load centers and equipped with power electronics converters to interface with the grid, therefore it is feasible for DE to provide reactive power (along with active power) locally for dynamic voltage regulation. In this paper, a synchronous condenser and a microturbine with an inverter interface are implemented in parallel in a distribution system to regulate the local voltage. Developed voltage control schemes for the inverter and the synchronous condenser are presented. Experimental results show that both the inverter and the synchronous condenser can regulate the local voltage instantaneously although the dynamic response of the inverter is much faster than the synchronous condenser. In a system with multiple DEs performing local voltage regulation, the interaction between the DEs is studied. The simulation results show the relationship between the voltages in the system and the reactive power required for the voltage regulation. Also, integrated voltage regulation (multiple DEs performing voltage regulation) can increase the voltage regulation capability of DEs and reduce the capital and operating costs.

  18. Design & Fabrication of a High-Voltage Photovoltaic Cell

    SciTech Connect (OSTI)

    Felder, Jennifer; /North Carolina State U. /SLAC

    2012-09-05T23:59:59.000Z

    Silicon photovoltaic (PV) cells are alternative energy sources that are important in sustainable power generation. Currently, applications of PV cells are limited by the low output voltage and somewhat low efficiency of such devices. In light of this fact, this project investigates the possibility of fabricating high-voltage PV cells on float-zone silicon wafers having output voltages ranging from 50 V to 2000 V. Three designs with different geometries of diffusion layers were simulated and compared in terms of metal coverage, recombination, built-in potential, and conduction current density. One design was then chosen and optimized to be implemented in the final device design. The results of the simulation serve as a feasibility test for the design concept and provide supportive evidence of the effectiveness of silicon PV cells as high-voltage power supplies.

  19. Voltage Sequence Control Based High-Current Rectifier System

    E-Print Network [OSTI]

    Paderborn, Universität

    of transformer. A passive filter is added at the primary side to achieve power factor improvement over the range of output voltage. This scheme is optimized to determine optimum turns ratio of the transformer and optimum not enforce unity power factor operation and guidelines provided by harmonic standards such as IEEE-519

  20. Energy Harvesting for Self-Powered Wireless Sensors

    E-Print Network [OSTI]

    Wardlaw, Jason

    2012-02-14T23:59:59.000Z

    transistor input referred offset voltage for 0.5?m CMOS and minimum length device. . . . . . . . . . . . . . 111 54 Low-voltage Low-power Inverter Based Comparator. . . . . . . . . . 114 55 Clock Voltage Doubler...

  1. Prebreakdown and breakdown phenomena in large oil gaps under AC

    SciTech Connect (OSTI)

    Saker, A.; Gournay, P.; Lesaint, O.; Tobazeon, R. [CNRS, Grenoble (France). Lab. d`Electrostatique et de Materiaux Dielectriques; Trinh, N.G. [Inst. de Recherche d`Hydro-Quebec, Varennes, Quebec (Canada); Boisdon, C. [Jeumont-Schneider Transformateurs, Lyon (France)

    1996-12-31T23:59:59.000Z

    This paper presents a study of prebreakdown and breakdown phenomena under AC voltage in mineral oil in large gaps to 60 cm. The investigations presented concern the study of streamers and the measurement of breakdown voltages in rod-plane and sphere-plane gaps. Also, the influence of a contamination by solid particles in the oil has been considered. A specific breakdown mode under AC voltage is evidenced, where bursts of streamers lead to the lowest breakdown fields recorded. Numerical values of the mean field in oil required for direct or burst breakdown modes are derived from the experiments. As a consequence, the great sensitivity to the presence of particles on EHV transformers insulation with large oil gaps is pointed out.

  2. 3.3.3AC Sweep AC . AC

    E-Print Network [OSTI]

    ­. DC ­ AC ­) .( . ­ ,, '­Spice .Spice . : 0 0 E1 PWR(V(%IN+, %IN . )2.3( Etable " . . : 00 V1 0Vdc E2 Pwr(V(%IN+, %IN-),2) ETABLE TABLE = (5

  3. An ultra-low voltage high gain operational transconductance amplifier for biomedical

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    An ultra-low voltage high gain operational transconductance amplifier for biomedical applications that work at ultra low voltage power supply. Moreover, low power dissipation is essential in these systems dissipation is also proposed in [5]. Differential pairs are commonly used as input stages, in an ultra-low

  4. High voltage electrical amplifier having a short rise time

    DOE Patents [OSTI]

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

    1991-01-01T23:59:59.000Z

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

  5. Comments on "Wall-plug (AC) power consumption of a very high energy e+/e- storage ring collider" by Marc Ross

    E-Print Network [OSTI]

    Blondel, A; Butterworth, A; Janot, P; Zimmermann, F; Aleksan, R; Azzi, P; Ellis, J; Klute, M; Zanetti, M

    2013-01-01T23:59:59.000Z

    The paper arXiv:1308.0735 questions some of the technical assumptions made by the TLEP Steering Group when estimating in arXiv:1305.6498 the power requirement for the very high energy e+e- storage ring collider TLEP. We show that our assumptions are based solidly on CERN experience with LEP and the LHC, as well accelerators elsewhere, and confirm our earlier baseline estimate of the TLEP power consumption.

  6. Temperature controlled high voltage regulator

    DOE Patents [OSTI]

    Chiaro, Jr., Peter J. (Clinton, TN); Schulze, Gerald K. (Knoxville, TN)

    2004-04-20T23:59:59.000Z

    A temperature controlled high voltage regulator for automatically adjusting the high voltage applied to a radiation detector is described. The regulator is a solid state device that is independent of the attached radiation detector, enabling the regulator to be used by various models of radiation detectors, such as gas flow proportional radiation detectors.

  7. Voltage Impacts of Utility-Scale Distributed Wind

    SciTech Connect (OSTI)

    Allen, A.

    2014-09-01T23:59:59.000Z

    Although most utility-scale wind turbines in the United States are added at the transmission level in large wind power plants, distributed wind power offers an alternative that could increase the overall wind power penetration without the need for additional transmission. This report examines the distribution feeder-level voltage issues that can arise when adding utility-scale wind turbines to the distribution system. Four of the Pacific Northwest National Laboratory taxonomy feeders were examined in detail to study the voltage issues associated with adding wind turbines at different distances from the sub-station. General rules relating feeder resistance up to the point of turbine interconnection to the expected maximum voltage change levels were developed. Additional analysis examined line and transformer overvoltage conditions.

  8. Control of power to an inductively heated part

    DOE Patents [OSTI]

    Adkins, Douglas R. (1620 Adelita Dr. NE., Albuquerque, NM 87112); Frost, Charles A. (1039 Red Oaks Loop NE., Albuquerque, NM 87122); Kahle, Philip M. (528 Longwood Loop NE., Rio Rancho, NM 87124); Kelley, J. Bruce (13200 Blue Corn Maiden Trail NE., Albuquerque, NM 87112); Stanton, Suzanne L. (2805 Palo Alto NE., Albuquerque, NM 87112)

    1997-01-01T23:59:59.000Z

    A process for induction hardening a part to a desired depth with an AC signal applied to the part from a closely coupled induction coil includes measuring the voltage of the AC signal at the coil and the current passing through the coil; and controlling the depth of hardening of the part from the measured voltage and current. The control system determines parameters of the part that are functions of applied voltage and current to the induction coil, and uses a neural network to control the application of the AC signal based on the detected functions for each part.

  9. Control of power to an inductively heated part

    DOE Patents [OSTI]

    Adkins, D.R.; Frost, C.A.; Kahle, P.M.; Kelley, J.B.; Stanton, S.L.

    1997-05-20T23:59:59.000Z

    A process for induction hardening a part to a desired depth with an AC signal applied to the part from a closely coupled induction coil includes measuring the voltage of the AC signal at the coil and the current passing through the coil; and controlling the depth of hardening of the part from the measured voltage and current. The control system determines parameters of the part that are functions of applied voltage and current to the induction coil, and uses a neural network to control the application of the AC signal based on the detected functions for each part. 6 figs.

  10. Pulsed Current-Voltage-Temperature Characteristics of AlGaN/GaN High Electron Mobility Transistor under Isothermal Conditions

    E-Print Network [OSTI]

    Seo, Kwang Seok

    , such as current collapse (power slump), the self-heating effect and the power scaling problem. In this paper, we have studied the self-heating effect using pulsed current-voltage (IV) and current- voltage self-heating affects the AlGaN/GaN HEMT's operation. It can be thought that a reason for the power

  11. High-voltage air-core pulse transformers

    SciTech Connect (OSTI)

    Rohwein, G. J.

    1981-01-01T23:59:59.000Z

    General types of air core pulse transformers designed for high voltage pulse generation and energy transfer applications are discussed with special emphasis on pulse charging systems which operate up to the multi-megavolt range. The design, operation, dielectric materials, and performance are described. It is concluded that high voltage air core pulse transformers are best suited to applications outside the normal ranges of conventional magnetic core transformers. In general these include charge transfer at high power levels and fast pulse generation with comparatively low energy. When properly designed and constructed, they are capable of delivering high energy transfer efficiency and have demonstrated superior high voltage endurance. The principal disadvantage of high voltage air core transformers is that they are not generally available from commercial sources. Consequently, the potential user must become thoroughly familiar with all aspects of design, fabrication and system application before he can produce a high performance transformer system. (LCL)

  12. IEEE 342 Node Low Voltage Networked Test System

    SciTech Connect (OSTI)

    Schneider, Kevin P.; Phanivong, Phillippe K.; Lacroix, Jean-Sebastian

    2014-07-31T23:59:59.000Z

    The IEEE Distribution Test Feeders provide a benchmark for new algorithms to the distribution analyses community. The low voltage network test feeder represents a moderate size urban system that is unbalanced and highly networked. This is the first distribution test feeder developed by the IEEE that contains unbalanced networked components. The 342 node Low Voltage Networked Test System includes many elements that may be found in a networked system: multiple 13.2kV primary feeders, network protectors, a 120/208V grid network, and multiple 277/480V spot networks. This paper presents a brief review of the history of low voltage networks and how they evolved into the modern systems. This paper will then present a description of the 342 Node IEEE Low Voltage Network Test System and power flow results.

  13. 2.3-MW Medium-Voltage, Three-Level Wind Energy Inverter Applying a Unique Bus Structure and 4.5-kV Si/SiC Hybrid Isolated Power Modules: Preprint

    SciTech Connect (OSTI)

    Erdman, W.; Keller, J.; Grider, D.; VanBrunt, E.

    2014-11-01T23:59:59.000Z

    A high-efficiency, 2.3-MW, medium-voltage, three-level inverter utilizing 4.5-kV Si/SiC (silicon carbide) hybrid modules for wind energy applications is discussed. The inverter addresses recent trends in siting the inverter within the base of multimegawatt turbine towers. A simplified split, three-layer laminated bus structure that maintains low parasitic inductances is introduced along with a low-voltage, high-current test method for determining these inductances. Feed-thru bushings, edge fill methods, and other design features of the laminated bus structure provide voltage isolation that is consistent with the 10.4-kV module isolation levels. Inverter efficiency improvement is a result of the (essential) elimination of the reverse recovery charge present in 4.5-kV Si PIN diodes, which can produce a significant reduction in diode turn-off losses as well as insulated-gate bipolar transistor (IGBT) turn-on losses. The hybrid modules are supplied in industry-standard 140 mm x 130 mm and 190 mm x 130 mm packages to demonstrate direct module substitution into existing inverter designs. A focus on laminated bus/capacitor-bank/module subassembly level switching performance is presented.

  14. Adaptive Nonlinear Control of Induction Motors through AC/DC/AC A. El Fadili*1

    E-Print Network [OSTI]

    Boyer, Edmond

    in a satisfactory way. First, a nonlinear model of the whole controlled system is developed within the Park be tightly regulated; (iii) the power factor correction (PFC) w.r.t. the power supply net must be performed control objectives (motor speed tracking, rotor flux regulation, DC link voltage regulation and unitary

  15. acs morphological study: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    (more) Yang, Emma Yunyi 2013-01-01 29 Study of supplementary controls for embedded HVDC links in a AC power system. Open Access Theses and Dissertations Summary: ??This...

  16. ac impedance study: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    high chromaticity. White, S 2014-01-01 37 Study of supplementary controls for embedded HVDC links in a AC power system. Open Access Theses and Dissertations Summary: ??This...

  17. Voltage control in pulsed system by predict-ahead control

    DOE Patents [OSTI]

    Payne, A.N.; Watson, J.A.; Sampayan, S.E.

    1994-09-13T23:59:59.000Z

    A method and apparatus for predict-ahead pulse-to-pulse voltage control in a pulsed power supply system is disclosed. A DC power supply network is coupled to a resonant charging network via a first switch. The resonant charging network is coupled at a node to a storage capacitor. An output load is coupled to the storage capacitor via a second switch. A de-Q-ing network is coupled to the resonant charging network via a third switch. The trigger for the third switch is a derived function of the initial voltage of the power supply network, the initial voltage of the storage capacitor, and the present voltage of the storage capacitor. A first trigger closes the first switch and charges the capacitor. The third trigger is asserted according to the derived function to close the third switch. When the third switch is closed, the first switch opens and voltage on the node is regulated. The second trigger may be thereafter asserted to discharge the capacitor into the output load. 4 figs.

  18. Pulsed voltage electrospray ion source and method for preventing analyte electrolysis

    DOE Patents [OSTI]

    Kertesz, Vilmos (Knoxville, TN); Van Berkel, Gary (Clinton, TN)

    2011-12-27T23:59:59.000Z

    An electrospray ion source and method of operation includes the application of pulsed voltage to prevent electrolysis of analytes with a low electrochemical potential. The electrospray ion source can include an emitter, a counter electrode, and a power supply. The emitter can include a liquid conduit, a primary working electrode having a liquid contacting surface, and a spray tip, where the liquid conduit and the working electrode are in liquid communication. The counter electrode can be proximate to, but separated from, the spray tip. The power system can supply voltage to the working electrode in the form of a pulse wave, where the pulse wave oscillates between at least an energized voltage and a relaxation voltage. The relaxation duration of the relaxation voltage can range from 1 millisecond to 35 milliseconds. The pulse duration of the energized voltage can be less than 1 millisecond and the frequency of the pulse wave can range from 30 to 800 Hz.

  19. Saving Megawatts with Voltage Optimization

    E-Print Network [OSTI]

    Wilson, T.; Bell, D.

    2010-01-01T23:59:59.000Z

    that had been installed at several electric utility distribution substations in the U.S. and Canada. These systems, being operated in Conservation Voltage Regulation mode, have provided significant energy conservation where they have been installed...

  20. Voltage tunable microwave ferrite resonator

    E-Print Network [OSTI]

    Oates, Daniel E.

    A novel method of implementing a tunable resonator using an applied voltage is presented. Stress is used to tune a microstrip resonator fabricated on a polycrystalline ferrite substrate. The stress was applied either ...

  1. ABBGroup-1-High voltage lab

    E-Print Network [OSTI]

    Basse, Nils Plesner

    . GENERATION System voltage: 12-24 kV Rated current: 6000-24000 A Max. short-circuit current: 50-500 kA TRANSMISSION System voltage: 72-800 kV Rated current: 2500-4000 A Max. short-circuit current: 25-63 k. It is designed to protect an electrical circuit from damage caused by overload or short-circuit. A circuit

  2. Optimal design of AC filter circuits in HVDC converter stations

    SciTech Connect (OSTI)

    Saied, M.M.; Khader, S.A. [Kuwait Univ. (Kuwait). Electrical and Computer Engineering Dept.

    1995-12-31T23:59:59.000Z

    This paper investigates the reactive power as well as the harmonic conditions on both the valve and the AC-network sides of a HVDC converter station. The effect of the AC filter circuits is accurately modeled. The program is then augmented by adding an optimization routine. It can identify the optimal filter configuration, yielding the minimum current distortion factor at the AC network terminals for a prespecified fundamental reactive power to be provided by the filter. Several parameter studies were also conducted to illustrate the effect of accidental or intentional deletion of one of the filter branches.

  3. www.eprg.group.cam.ac.uk EPRGWORKINGPAPER

    E-Print Network [OSTI]

    Aickelin, Uwe

    www.eprg.group.cam.ac.uk EPRGWORKINGPAPER Abstract Reforming Small Power Systems under Political Nepal and Tooraj Jamasb This paper assesses the electricity sector reforms across small power systems make power sector reform in Nepal and similar small systems a more complex process. As international

  4. Excitation control for improving transient stability limit and voltage regulation with dynamic loads

    E-Print Network [OSTI]

    Pota, Himanshu Roy

    on the complex nonlinear simulation and the others are based on the linearised power system model. Although control techniques in power systems as one of the most promising application areas; see Bevrani and Hiyama to improve the power system transient stability and voltage regulation in interconnected power systems

  5. Systems and methods for process and user driven dynamic voltage and frequency scaling

    DOE Patents [OSTI]

    Mallik, Arindam (Evanston, IL); Lin, Bin (Hillsboro, OR); Memik, Gokhan (Evanston, IL); Dinda, Peter (Evanston, IL); Dick, Robert (Evanston, IL)

    2011-03-22T23:59:59.000Z

    Certain embodiments of the present invention provide a method for power management including determining at least one of an operating frequency and an operating voltage for a processor and configuring the processor based on the determined at least one of the operating frequency and the operating voltage. The operating frequency is determined based at least in part on direct user input. The operating voltage is determined based at least in part on an individual profile for processor.

  6. AC breakdown strength of N2, SF6 and a mixture of N2+SF6 containing a small amount of SF6

    SciTech Connect (OSTI)

    Mardikyan, K.; Kalenderli, O. [Istanbul Technical Univ. (Turkey). Electric-Electronics Faculty; Ersen, O.; Canarslan, E. [Schneider Electric Co., Istanbul (Turkey)

    1996-12-31T23:59:59.000Z

    AC breakdown strengths of N{sub 2}, SF{sub 6} and a mixture of N{sub 2}+SF{sub 6} containing 1% of SF{sub 6} were experimentally studied. For this purpose, 50 Hz AC breakdown voltages in both uniform and non-uniform fields up to a pressure of 400 kPa from 50 kPa were measured. Test results show that the addition of 1% of SF{sub 6} to nitrogen increases the breakdown voltage up to 250 kPa in a non-uniform field. The relative breakdown strength of the mixture with respect to components was also calculated in 50 Hz AC voltage. The analysis of Paschen curves reveals an improvement of 40% in the breakdown strength of mixture in uniform field but in non-uniform fields, the maximum AC breakdown voltage of the mixture is 24% lower than that of pure SF{sub 6}.

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

    DOE Patents [OSTI]

    Murty, Balarama Vempaty (West Bloomfield, MI)

    2000-01-01T23:59:59.000Z

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

  8. High Voltage DC Transmission 1.0 Introduction

    E-Print Network [OSTI]

    McCalley, James D.

    1 High Voltage DC Transmission 1.0 Introduction HVDC has been applied in electric power systems for many years now. Figure 1 illustrates worldwide many of the HVDC applications [1]. Fig. 1 ABB provides a webpage which summarizes HVDC projects by type and capacity or by commissioning year [2]. Wikipedia [3

  9. Gemini: A Non-Invasive, Energy-Harvesting True Power Meter Bradford Campbell and Prabal Dutta

    E-Print Network [OSTI]

    Dutta, Prabal

    measure voltage (since true power requires sample-by-sample multiplication of current and voltage to the voltage channel they can only measure apparent power, at best, and certainly not true power. A small capable of measuring true power. Two insights enable this design point: 1) a power meter can harvest

  10. Low Insertion HVDC Circuit Breaker: Magnetically Pulsed Hybrid Breaker for HVDC Power Distribution Protection

    SciTech Connect (OSTI)

    None

    2012-01-09T23:59:59.000Z

    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-voltage 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.

  11. High voltage transformers. (Latest citations from the Inspec database). NewSearch

    SciTech Connect (OSTI)

    Not Available

    1994-11-01T23:59:59.000Z

    The bibliography contains citations concerning materials and performance of insulators used for high voltage transformers. Topics examine use of mica-fibers, gases, mica filled epoxies, and ceramics. Effects of insulation aging are reviewed, and acceptance testing of high voltage power transformers and apparatus is also examined. (Contains a minimum of 104 citations and includes a subject term index and title list.)

  12. An Ensemble Empirical Mode Decomposition Approach for Voltage Sag Detection in a Smart Grid Context

    E-Print Network [OSTI]

    Brest, Université de

    An Ensemble Empirical Mode Decomposition Approach for Voltage Sag Detection in a Smart Grid Context Yassine Amirat1,2 , Mohamed Benbouzid2 , Tianzhen Wang3 and Sylvie Turri2 Abstract­Smart grids have become, using the instantaneous power for voltage sags detection in smart grids. Copyright © 2013 Praise Worthy

  13. Supply Voltage Degradation Aware Analytical Placement Andrew B. Kahng Bao Liu Qinke Wang

    E-Print Network [OSTI]

    Liu, Bao

    Supply Voltage Degradation Aware Analytical Placement Andrew B. Kahng Bao Liu Qinke Wang Computer@cs.ucsd.edu} Abstract Increasingly significant power/ground supply voltage degradation in nanometer VLSI designs leads to system per- formance degradation and even malfunction. Existing tech- niques focus on design

  14. Voltage grid support of DFIG wind turbines during grid faults Anca D. Hansen1

    E-Print Network [OSTI]

    Voltage grid support of DFIG wind turbines during grid faults Anca D. Hansen1 , Gabriele Michalke2 Abstract The fault ride-through and grid support capabilities of the doubly fed induction generator (DFIG and their contribution to support the grid, i.e. to the voltage control in the power system, during grid faults

  15. A new technique to reject dc-link voltage ripple in PWM inverters

    E-Print Network [OSTI]

    Shireen, Wajiha

    1990-01-01T23:59:59.000Z

    to acknowledge the support of my husband and parents. TA. BLE OF CONTENTS CHAPTER I INTRODUCTION Page I. l Inverter Power Supplies 1. 2 Output Voltage Control 1. 2. 1 Control Of Voltage Supplied To The Inverter I. 2. 2 Control Of Voltage Within... and output of Stage 3 78 34 Exact solution of the switching angle trajectories for harmonic elimination with voltage control (M). 85 CHAPTER I INTRODUCTION Finding ways to control the flow of electricity has been a. goal of inventors and scientists...

  16. High voltage switch triggered by a laser-photocathode subsystem

    DOE Patents [OSTI]

    Chen, Ping; Lundquist, Martin L.; Yu, David U. L.

    2013-01-08T23:59:59.000Z

    A spark gap switch for controlling the output of a high voltage pulse from a high voltage source, for example, a capacitor bank or a pulse forming network, to an external load such as a high gradient electron gun, laser, pulsed power accelerator or wide band radar. The combination of a UV laser and a high vacuum quartz cell, in which a photocathode and an anode are installed, is utilized as triggering devices to switch the spark gap from a non-conducting state to a conducting state with low delay and low jitter.

  17. Effects of Distributed Energy Resources on Conservation Voltage Reduction (CVR)

    SciTech Connect (OSTI)

    Singh, Ruchi; Tuffner, Francis K.; Fuller, Jason C.; Schneider, Kevin P.

    2011-10-10T23:59:59.000Z

    Conservation Voltage Reduction (CVR) is one of the cheapest technologies which can be intelligently leveraged to provide considerable energy savings. The addition of renewables in the form of distributed resources can affect the entire power system, but more importantly, affects the traditional substation control schemes at the distribution level. This paper looks at the effect on energy consumption, peak load reduction, and voltage profile changes due to the addition of distributed generation in a distribution feeder using combinations of volt var control. An IEEE 13-node system is used to simulate the various cases. Energy savings and peak load reduction for different simulation scenarios are compared.

  18. Optically triggered high voltage switch network and method for switching a high voltage

    DOE Patents [OSTI]

    El-Sharkawi, Mohamed A. (Renton, WA); Andexler, George (Everett, WA); Silberkleit, Lee I. (Mountlake Terrace, WA)

    1993-01-19T23:59:59.000Z

    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).

  19. IEEE TRANSACTIONS ON POWER SYSTEMS, VOL. 8, NO. 1, FEBRUARY 1993, PP. 1 8. POINT OF COLLAPSE AND CONTINUATION METHODS FOR LARGE

    E-Print Network [OSTI]

    Cañizares, Claudio A.

    HVDC transmission, area interchange power control, regulating transformers, and voltage and reactive

  20. Voltage Stabilization in Microgrids via Quadratic Droop Control John W. Simpson-Porco, Florian Dorfler, and Francesco Bullo

    E-Print Network [OSTI]

    Bullo, Francesco

    -voltage electrical networks equipped with DC/AC inverters ("micro- grids"). It is generally believed that high¨orfler, and Francesco Bullo Abstract-- Motivated by the growing interest in energy tech- nology and smart grid distribution networks, heterogeneously composed of distributed generation, storage, load, and managed

  1. June 2014 Most Viewed Documents for Power Generation And Distribution...

    Office of Scientific and Technical Information (OSTI)

    Documents for Power Generation And Distribution Science Subject Feed Seventh Edition Fuel Cell Handbook NETL (2004) 118 > Electric power high-voltage transmission lines:...

  2. Catalog of DC Appliances and Power Systems

    E-Print Network [OSTI]

    Garbesi, Karina

    2012-01-01T23:59:59.000Z

    at its maximum power output for the given solar conditions.Solar Electric Incentive Programs. [38] Module power outputs,power output (a) and voltages (b) of PV modules satisfying the Guidelines for California’s Solar

  3. High voltage MOSFET switching circuit

    DOE Patents [OSTI]

    McEwan, T.E.

    1994-07-26T23:59:59.000Z

    The problem of source lead inductance in a MOSFET switching circuit is compensated for by adding an inductor to the gate circuit. The gate circuit inductor produces an inductive spike which counters the source lead inductive drop to produce a rectangular drive voltage waveform at the internal gate-source terminals of the MOSFET. 2 figs.

  4. High voltage MOSFET switching circuit

    DOE Patents [OSTI]

    McEwan, Thomas E. (Livermore, CA)

    1994-01-01T23:59:59.000Z

    The problem of source lead inductance in a MOSFET switching circuit is compensated for by adding an inductor to the gate circuit. The gate circuit inductor produces an inductive spike which counters the source lead inductive drop to produce a rectangular drive voltage waveform at the internal gate-source terminals of the MOSFET.

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

    SciTech Connect (OSTI)

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

    2008-03-03T23:59:59.000Z

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

  6. Improving Process Control Immunity to Supply Voltage Sags in Petroleum and Chemical Industries

    E-Print Network [OSTI]

    Mansoor, A.; Dorr, D.; Olson, G.

    IMPROVING PROCESS CONTROL IMMUNITY TO SUPPLY VOLTAGE SAGS IN PETROLEUM AND CHEMICAL INDUSTRIES Douglas Dorr and Arshad Mansoor EPRI Power Electronics Applications Center Knoxville, TN ABSTRACT In the modem industrial facility, many... by EPRI's Power Quality Test Facility clearly shows that CVT's are an excellent solution for voltage sag problems when they are sized properly. The optimum sizing is achieved when the CVT is loaded to no more than about 40 Figure 3. Batteryless UPS...

  7. A Dynamic Voltage Scaling Controller for Maximum Energy Saving Across Full Range of Load Conditions

    E-Print Network [OSTI]

    Ng, Wai Tung

    to an explosive increase in both power density and total power consumption in modem VLSI circuits. In order or low power mode, energy saving from dynamic voltage scaling (DVS) is limited due to very poor efficiency of the PWM DC/DC converter operating at light load conditions, resulting in shorter than expected

  8. Currents' Physical Components (CPC) In Circuits with Nonsinusoidal Voltages and Currents

    E-Print Network [OSTI]

    Czarnecki, Leszek S.

    and transformer turn ratio is 1:1, the active power at the supply terminals is P = 115.1 kW, while the apparentCurrents' Physical Components (CPC) In Circuits with Nonsinusoidal Voltages and Currents Part 2 state of discussions on power phenomena, power definitions and compensation in three-phase three

  9. Operating-System Directed Power Reduction Yung-Hsiang Lu

    E-Print Network [OSTI]

    Lu, Jiaheng

    to workloads is called dynamic power management (DPM) [3]. Power managers (PM) determine power state transitions accord- ing to their shutdown rules (also called policies). Power management can be generalized, power management includes dynamic voltage setting [7] and variable clock speeds [14]. Setting voltages

  10. Three phase AC motor controller

    DOE Patents [OSTI]

    Vuckovich, Michael (Elizabeth, PA); Wright, Maynard K. (Bethel Park, PA); Burkett, John P. (South Huntington Township, Westmoreland County, PA)

    1984-03-20T23:59:59.000Z

    A motor controller for a three phase AC motor (10) which is adapted to operate bidirectionally from signals received either from a computer (30) or a manual control (32). The controller is comprised of digital logic circuit means which implement a forward and reverse command signal channel (27, 29) for the application of power through the forward and reverse power switching relays (16, 18, 20, 22). The digital logic elements are cross coupled to prevent activation of both channels simultaneously and each includes a plugging circuit (65, 67) for stopping the motor upon the removal of control signal applied to one of the two channels (27, 29) for a direction of rotation desired. Each plugging circuit (65, 67) includes a one-shot pulse signal generator (88, 102) which outputs a single pulse signal of predetermined pulsewidth which is adapted to inhibit further operation of the application of power in the channel which is being activated and to apply a reversal command signal to the other channel which provides a reversed phase application of power to the motor for a period defined by the pulse-width output of the one-shot signal generator to plug the motor (10) which will then be inoperative until another rotational command signal is applied to either of the two channels.

  11. Voltage controlled MESFET pulse shape generator

    SciTech Connect (OSTI)

    Burkhart, S.C.

    1994-10-26T23:59:59.000Z

    A programmable pulse shape generator capable of producing pulse shapes for Nova and Beamlet has been designed and simulated using the circuit code SPICE. The design utilizes power MESFETS, which are commonly used in microwave amplifiers. The pulse shape is varied by setting a bias voltage on each in a chain of MESFETS with a 200 ps temporal resolution. The electrical pulse then drives an integrated electro-optic modulator similar to what is on Beamlet. Pulse shapes 22 and 25, used on Nova, have been generated by this design. There is no fundamental barrier to making such a pulse generator for use on the National Ignition Facility. In fact, the longer time scales on the NIF pulse will ease the high speed requirements of the pulse shape generator allowing the use of less expensive components. The next step will be to build a prototype circuit for initial testing on Beamlet and Nova.

  12. Further investigation of electronic multiplication of voltages by use of logarithms

    E-Print Network [OSTI]

    Biard, James Robert

    1957-01-01T23:59:59.000Z

    efficient use of the maximum power ratings of the output tube or power supplies. When the positive feedback in this amplifier is properly adjusted, infinite gain results at DC. That is, the voltage between control grid and ground does not vary for a... change in output voltage. Since the control grid remains at ground po? tential, any change in output must be due to a change in cathode-to-ground voltage. The proper bias for the pentode screen is obtained with a resistive divider from B+ to a point...

  13. Bifurcation Analysis of Various Power System Models

    E-Print Network [OSTI]

    Cańizares, Claudio A.

    modeling, voltage collapse. I. Introduction Voltage stability problems in power systems may occurBifurcation Analysis of Various Power System Models William D. Rosehart Claudio A. Ca This paper presents the bifurcation analysis of a detailed power system model composed of an aggregated

  14. www.eprg.group.cam.ac.uk EPRGWORKINGPAPERNON-TECHNICALSUMMARY

    E-Print Network [OSTI]

    Aickelin, Uwe

    www.eprg.group.cam.ac.uk EPRGWORKINGPAPERNON-TECHNICALSUMMARY Reforming Small Power Systems under Rabindra Nepal and Tooraj Jamasb The pioneering electricity sector reforms in developing Latin American of `successful and comprehensive electricity reforms' in many less-developed countries like Nepal. Nepal's power

  15. Fig. 5. The influence of the network cross-traffic on the ability of the SANET to stabilize the generator's voltage

    E-Print Network [OSTI]

    Branicky, Michael S.

    for dynamical systems simulations. Example: Agent/Plant [2] Third direction: marry a full-fledged network.g., Standard, Power systems, Hydraulics, Pneumatics, Power train) Has commercial and open source simulation the generator's voltage under the varying load. The plots show the line voltage and power for two cases

  16. High-efficiency grid-connected photovoltaic module integrated converter system with high-speed communication interfaces for small-scale distribution power generation

    SciTech Connect (OSTI)

    Choi, Woo-Young; Lai, Jih-Sheng (Jason) [Future Energy Electronics Center, Department of Electrical and Computer Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA (United States)

    2010-04-15T23:59:59.000Z

    This paper presents a high-efficiency grid-connected photovoltaic (PV) module integrated converter (MIC) system with reduced PV current variation. The proposed PV MIC system consists of a high-efficiency step-up DC-DC converter and a single-phase full-bridge DC-AC inverter. An active-clamping flyback converter with a voltage-doubler rectifier is proposed for the step-up DC-DC converter. The proposed step-up DC-DC converter reduces the switching losses by eliminating the reverse-recovery current of the output rectifying diodes. To reduce the PV current variation introduced by the grid-connected inverter, a PV current variation reduction method is also suggested. The suggested PV current variation reduction method reduces the PV current variation without any additional components. Moreover, for centralized power control of distributed PV MIC systems, a PV power control scheme with both a central control level and a local control level is presented. The central PV power control level controls the whole power production by sending out reference power signals to each individual PV MIC system. The proposed step-up DC-DC converter achieves a high-efficiency of 97.5% at 260 W output power to generate the DC-link voltage of 350 V from the PV voltage of 36.1 V. The PV MIC system including the DC-DC converter and the DC-AC inverter achieves a high-efficiency of 95% with the PV current ripple less than 3% variation of the rated PV current. (author)

  17. Efficient Switches for Solar Power Conversion: Four Quadrant GaN Switch Enabled Three Phase Grid-Tied Microinverters

    SciTech Connect (OSTI)

    None

    2012-02-13T23:59:59.000Z

    Solar ADEPT Project: Transphorm is developing power switches for new types of inverters that improve the efficiency and reliability of converting energy from solar panels into useable electricity for the grid. Transistors act as fast switches and control the electrical energy that flows in an electrical circuit. Turning a transistor off opens the circuit and stops the flow of electrical current; turning it on closes the circuit and allows electrical current to flow. In this way a transistor can be used to convert DC from a solar panel into AC for use in a home. Transphorm’s transistors will enable a single semiconductor device to switch electrical currents at high-voltage in both directions—making the inverter more compact and reliable. Transphorm is using Gallium Nitride (GaN) as a semiconductor material in its transistors instead of silicon, which is used in most conventional transistors, because GaN transistors have lower losses at higher voltages and switching frequencies.

  18. Hybrid switch for resonant power converters

    DOE Patents [OSTI]

    Lai, Jih-Sheng; Yu, Wensong

    2014-09-09T23:59:59.000Z

    A hybrid switch comprising two semiconductor switches connected in parallel but having different voltage drop characteristics as a function of current facilitates attainment of zero voltage switching and reduces conduction losses to complement reduction of switching losses achieved through zero voltage switching in power converters such as high-current inverters.

  19. A/AC.105/C.1/2014/CRP.15 5 February 2014

    E-Print Network [OSTI]

    Schrijver, Karel

    on the Peaceful Uses of Outer Space Scientific and Technical Subcommittee Fifty-first session Vienna, 10 infrastructure, including high voltage electrical transmission systems and pipelines. #12;2 V.14-00677 A/AC.105/C space situational awareness); and potential loss of space-based services, particularly environmental

  20. System and method for monitoring and controlling stator winding temperature in a de-energized AC motor

    DOE Patents [OSTI]

    Lu, Bin (Kenosha, WI); Luebke, Charles John (Sussex, WI); Habetler, Thomas G. (Snellville, GA); Zhang, Pinjia (Atlanta, GA); Becker, Scott K. (Oak Creek, WI)

    2011-12-27T23:59:59.000Z

    A system and method for measuring and controlling stator winding temperature in an AC motor while idling is disclosed. The system includes a circuit having an input connectable to an AC source and an output connectable to an input terminal of a multi-phase AC motor. The circuit further includes a plurality of switching devices to control current flow and terminal voltages in the multi-phase AC motor and a controller connected to the circuit. The controller is configured to activate the plurality of switching devices to create a DC signal in an output of the motor control device corresponding to an input to the multi-phase AC motor, determine or estimate a stator winding resistance of the multi-phase AC motor based on the DC signal, and estimate a stator temperature from the stator winding resistance. Temperature can then be controlled and regulated by DC injection into the stator windings.

  1. Princeton Plasma Physics Lab - AC power

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's Possible forPortsmouth/Paducah47,193.7 348,016.0 336,514.0 350,723.3 353,325.06,650.0

  2. Biased low differential input impedance current receiver/converter device and method for low noise readout from voltage-controlled detectors

    DOE Patents [OSTI]

    Degtiarenko, Pavel V. (Williamsburg, VA); Popov, Vladimir E. (Newport News, VA)

    2011-03-22T23:59:59.000Z

    A first stage electronic system for receiving charge or current from voltage-controlled sensors or detectors that includes a low input impedance current receiver/converter device (for example, a transimpedance amplifier), which is directly coupled to the sensor output, a source of bias voltage, and the device's power supply (or supplies), which use the biased voltage point as a baseline.

  3. Dynamic performance of static and synchronous compensators at an HVDC inverter bus in a very weak AC system

    SciTech Connect (OSTI)

    Nayak, O.B.; Gole, A.M. (Univ. of Manitoba, Winnipeg (Canada)); Chapman, D.G.; Davies, J.B. (Manitoba Hydro, Winnipeg (Canada))

    1994-08-01T23:59:59.000Z

    This paper discusses the performance of dynamic voltage control devices at the inverters of very weak ac systems. The types of compensation considered are: (a) static var compensator (SVC), (b) synchronous compensator (SC), (c) a mix of the two and (d) fixed capacitors. Although the primary purpose of these compensators is to control voltage at the ac bus, their dynamic performance during system disturbances is a very important factor. The investigation includes the behavior of the various voltage control options under ac and dc disturbances. The paper shows that the SVC has the fastest response for load rejection type of overvoltages, but can cause serious problems with recovery during undervoltages caused by single phase faults. The CIGRE benchmark model for HVdc control studies has been modified and used in this study. In particular the effect of local load has been included.

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

    DOE Patents [OSTI]

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

    2001-01-01T23:59:59.000Z

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

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

    DOE Patents [OSTI]

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

    2000-01-01T23:59:59.000Z

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

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

    DOE Patents [OSTI]

    Vail III, William Banning; Momii, Steven Thomas

    2003-06-10T23:59:59.000Z

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

  7. Multilevel-Dc-Bus Inverter For Providing Sinusoidal And Pwm Electrical Machine Voltages

    DOE Patents [OSTI]

    Su, Gui-Jia [Knoxville, TN

    2005-11-29T23:59:59.000Z

    A circuit for controlling an ac machine comprises a full bridge network of commutation switches which are connected to supply current for a corresponding voltage phase to the stator windings, a plurality of diodes, each in parallel connection to a respective one of the commutation switches, a plurality of dc source connections providing a multi-level dc bus for the full bridge network of commutation switches to produce sinusoidal voltages or PWM signals, and a controller connected for control of said dc source connections and said full bridge network of commutation switches to output substantially sinusoidal voltages to the stator windings. With the invention, the number of semiconductor switches is reduced to m+3 for a multi-level dc bus having m levels. A method of machine control is also disclosed.

  8. Power conversion apparatus and method

    DOE Patents [OSTI]

    Su, Gui-Jia (Knoxville, TN)

    2012-02-07T23:59:59.000Z

    A power conversion apparatus includes an interfacing circuit that enables a current source inverter to operate from a voltage energy storage device (voltage source), such as a battery, ultracapacitor or fuel cell. The interfacing circuit, also referred to as a voltage-to-current converter, transforms the voltage source into a current source that feeds a DC current to a current source inverter. The voltage-to-current converter also provides means for controlling and maintaining a constant DC bus current that supplies the current source inverter. The voltage-to-current converter also enables the current source inverter to charge the voltage energy storage device, such as during dynamic braking of a hybrid electric vehicle, without the need of reversing the direction of the DC bus current.

  9. Utility-Side Voltage and PQ Control with Inverter-based Photovoltaic Systems

    SciTech Connect (OSTI)

    Adhikari, Sarina [ORNL] [ORNL; Xu, Yan [ORNL] [ORNL; Li, Fangxing [ORNL] [ORNL; Li, Huijuan [ORNL] [ORNL; Kueck, John D [ORNL] [ORNL; Snyder, Isabelle B [ORNL] [ORNL; Barker, Thomas J. [Southern California Edison RTTC] [Southern California Edison RTTC; Hite, Ronald [Southern California Edison RTTC] [Southern California Edison RTTC

    2011-01-01T23:59:59.000Z

    Distributed energy resources (DER) are small generators located close to the load centers. The DERs that are integrated to the grid with the power electronic converter interfaces are capable of providing nonactive power in addition to active power. Hence, they are capable of regulating the voltages of the weak buses in the distribution systems. This paper discusses the voltage control capability of photovoltaic (PV) systems as compared to the traditional capacitor banks. The simulation results prove the effectiveness of dynamic voltage control capability of inverter-based PV. With the proper control algorithm, the active and nonactive power from the DERs like battery banks or solar photovoltaic can be controlled independently. This paper also presents the scenario of controlling the active and nonactive power from the PV array to track and supply the local load.

  10. HVDC-AC system interaction from AC harmonics. Volume 1. Harmonic impedance calculations. Final report

    SciTech Connect (OSTI)

    Breuer, G D; Chow, J H; Lindh, C B; Miller, N W; Numrich, F H; Price, W W; Turner, A E; Whitney, R R

    1982-09-01T23:59:59.000Z

    Improved methods are needed to characterize ac system harmonic behavior for ac filter design for HVDC systems. The purpose of this General Electric Company RP1138 research is to evaluate the present filter design practice and to investigate methods for calculating system harmonic impedances. An overview of ac filter design for HVDC systems and a survey of literature related to filter design have been performed. Two methods for calculating system harmonic impedances have been investigated. In the measurement method, an instrumentation system for measuring system voltage and current has been assembled. Different schemes of using the measurements to calculate system harmonic impedances have been studied. In the analytical method, a procedure to include various operating conditions has been proposed. Computer programs for both methods have been prepared, and the results of the measurement and analytical methods analyzed. A conclusion of the project is that the measurement and analytical methods both provided reasonable results. There are correlations between the measured and analytical results for most harmonics, although there are discrepancies between the assumptions used in the two methods. A sensitivity approach has been proposed to further correlate the results. From the results of the analysis, it is recommended that both methods should be tested further. For the measurement method, more testing should be done to cover different system operating conditions. In the analytical method, more detailed models for representing system components should be studied. In addition, alternative statistical and sensitivity approaches should be attempted.

  11. Strategies for Voltage Control and Transient Stability Assessment

    SciTech Connect (OSTI)

    Hiskens, Ian A.

    2013-09-25T23:59:59.000Z

    As wind generation grows, its influence on power system performance will becoming increasingly noticeable. Wind generation di#11;ffers from traditional forms of generation in numerous ways though, motivating the need to reconsider the usual approaches to power system assessment and performance enhancement. The project has investigated the impact of wind generation on transient stability and voltage control, identifying and addressing issues at three distinct levels of the power system: 1) at the device level, the physical characteristics of wind turbine generators (WTGs) are quite unlike those of synchronous machines, 2) at the wind-farm level, the provision of reactive support is achieved through coordination of numerous dissimilar devices, rather than straightforward generator control, and 3) from a systems perspective, the location of wind-farms on the sub-transmission network, coupled with the variability inherent in their power output, can cause complex voltage control issues. The project has sought to develop a thorough understanding of the dynamic behaviour of type-3 WTGs, and in particular the WECC generic model. The behaviour of such models is governed by interactions between the continuous dynamics of state variables and discrete events associated with limits. It was shown that these interactions can be quite complex, and may lead to switching deadlock that prevents continuation of the trajectory. Switching hysteresis was proposed for eliminating deadlock situations. Various type-3 WTG models include control blocks that duplicate integrators. It was shown that this leads to non-uniqueness in the conditions governing steady-state, and may result in pre- and post-disturbance equilibria not coinciding. It also gives rise to a zero eigenvalue in the linearized WTG model. In order to eliminate the anomalous behaviour revealed through this investigation, WECC has now released a new generic model for type-3 WTGs. Wind-farms typically incorporate a variety of voltage control equipment including tapchanging transformers, switched capacitors, SVCs, STATCOMs and the WTGs themselves. The project has considered the coordinated control of this equipment, and has addressed a range of issues that arise in wind-farm operation. The #12;first concerns the ability of WTGs to meet reactive power requirements when voltage saturation in the collector network restricts the reactive power availability of individual generators. Secondly, dynamic interactions between voltage regulating devices have been investigated. It was found that under certain realistic conditions, tap-changing transformers may exhibit instability. In order to meet cost, maintenance, fault tolerance and other requirements, it is desirable for voltage control equipment to be treated as an integrated system rather than as independent devices. The resulting high-level scheduling of wind-farm reactive support has been investigated. In addressing this control problem, several forms of future information were considered, including exact future knowledge and stochastic predictions. Deterministic and Stochastic Dynamic Programming techniques were used in the development of control algorithms. The results demonstrated that while exact future knowledge is very useful, simple prediction methods yield little bene#12;fit. The integration of inherently variable wind generation into weak grids, particularly subtransmission networks that are characterized by low X=R ratios, aff#11;ects bus voltages, regulating devices and line flows. The meshed structure of these networks adds to the complexity, especially when wind generation is distributed across multiple nodes. A range of techniques have been considered for analyzing the impact of wind variability on weak grids. Sensitivity analysis, based on the power-flow Jacobian, was used to highlight sections of a system that are most severely a#11;ffected by wind-power variations. A continuation power flow was used to determine parameter changes that reduce the impact of wind-power variability. It was also used to explore interactions betw

  12. Analysis and design of power conditioning systems 

    E-Print Network [OSTI]

    Harfman Todorovic, Maja

    2009-05-15T23:59:59.000Z

    power conditioner consisting of DC-DC and DC-AC converters is required for load interface. The design of power conditioners is driven by the application. This dissertation presents several different solutions for applications ranging from low...

  13. Voltage Vehicles | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere IRaghuraji Agro IndustriesTown of Ladoga,planningFlowmeterUtah: Energydba Vision Motor CorpEIAVogtVoltage

  14. Soft Magnetic Materials in High-Frequency, High-Power Conversion Applications

    E-Print Network [OSTI]

    McHenry, Michael E.

    Voltage DC (HVDC) technologies aim to improve the effi- ciency of power networks and benefit from high

  15. Control of Distributed Energy Resources for Reactive Power Support

    E-Print Network [OSTI]

    Liberzon, Daniel

    power support for voltage control in electric power systems. Rather than controlling each power support, which is critical in electric power systems for voltage stability and control [6]. Thus groups, that belong to a chain of command structure much like the Incident Command System (ICS) used

  16. Outdoor PV Module Degradation of Current-Voltage Parameters: Preprint

    SciTech Connect (OSTI)

    Smith, R. M.; Jordan, D. C.; Kurtz, S. R.

    2012-04-01T23:59:59.000Z

    Photovoltaic (PV) module degradation rate analysis quantifies the loss of PV power output over time and is useful for estimating the impact of degradation on the cost of energy. An understanding of the degradation of all current-voltage (I-V) parameters helps to determine the cause of the degradation and also gives useful information for the design of the system. This study reports on data collected from 12 distinct mono- and poly-crystalline modules deployed at the National Renewable Energy Laboratory (NREL) in Golden, Colorado. Most modules investigated showed < 0.5%/year decrease in maximum power due to short-circuit current decline.

  17. Commercialization of Medium Voltage HTS Triax TM Cable Systems

    SciTech Connect (OSTI)

    Knoll, David

    2012-12-31T23:59:59.000Z

    The original project scope that was established in 2007 aimed to install a 1,700 meter (1.1 mile) medium voltage HTS Triax{TM} cable system into the utility grid in New Orleans, LA. In 2010, however, the utility partner withdrew from the project, so the 1,700 meter cable installation was cancelled and the scope of work was reduced. The work then concentrated on the specific barriers to commercialization of HTS cable technology. The modified scope included long-length HTS cable design and testing, high voltage factory test development, optimized cooling system development, and HTS cable life-cycle analysis. In 2012, Southwire again analyzed the market for HTS cables and deemed the near term market acceptance to be low. The scope of work was further reduced to the completion of tasks already started and to testing of the existing HTS cable system in Columbus, OH. The work completed under the project included: • Long-length cable modeling and analysis • HTS wire evaluation and testing • Cable testing for AC losses • Optimized cooling system design • Life cycle testing of the HTS cable in Columbus, OH • Project management. The 200 meter long HTS Triax{TM} cable in Columbus, OH was incorporated into the project under the initial scope changes as a test bed for life cycle testing as well as the site for an optimized HTS cable cooling system. The Columbus cable utilizes the HTS TriaxTM design, so it provided an economical tool for these of the project tasks.

  18. Utility Test Results of a 2-Megawatt, 10-Second Reserve-Power System

    SciTech Connect (OSTI)

    BALL,GREG J.; NORRIS,BENJAMIN L.

    1999-10-01T23:59:59.000Z

    This report documents the 1996 evaluation by Pacific Gas and Electric Company of an advanced reserve-power system capable of supporting 2 MW of load for 10 seconds. The system, developed under a DOE Cooperative Agreement with AC Battery Corporation of East Troy, Wisconsin, contains battery storage that enables industrial facilities to ''ride through'' momentary outages. The evaluation consisted of tests of system performance using a wide variety of load types and operating conditions. The tests, which included simulated utility outages and voltage sags, demonstrated that the system could provide continuous power during utility outages and other disturbances and that it was compatible with a variety of load types found at industrial customer sites.

  19. ACEEE Int. J. on Electrical and Power Engineering, Vol. 02, No. 01, Feb 2011 2011 ACEEE

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    as other power systems troubles such as damping of voltage oscillations . The basic principle of active the load current, harmonics and voltage oscillations. This is called unified power quality conditioner; its.IJEPE.02.01.78 36 Design of UPQC with Minimization of DC Link voltage for the Improvement of Power

  20. Comprehensive Diagnosis of Complex Electrical Power Distribution Systems

    E-Print Network [OSTI]

    Daigle, Matthew

    Comprehensive Diagnosis of Complex Electrical Power Distribution Systems Indranil Roychoudhury Abstract: Electrical power distribution systems are composed of heterogeneous components, which include and discrete faults in electrical power distribution systems that include dc and ac components. We use a hybrid

  1. Optimizing performance per watt on GPUs in High Performance Computing: temperature, frequency and voltage effects

    E-Print Network [OSTI]

    Price, D C; Barsdell, B R; Babich, R; Greenhill, L J

    2014-01-01T23:59:59.000Z

    The magnitude of the real-time digital signal processing challenge attached to large radio astronomical antenna arrays motivates use of high performance computing (HPC) systems. The need for high power efficiency (performance per watt) at remote observatory sites parallels that in HPC broadly, where efficiency is an emerging critical metric. We investigate how the performance per watt of graphics processing units (GPUs) is affected by temperature, core clock frequency and voltage. Our results highlight how the underlying physical processes that govern transistor operation affect power efficiency. In particular, we show experimentally that GPU power consumption grows non-linearly with both temperature and supply voltage, as predicted by physical transistor models. We show lowering GPU supply voltage and increasing clock frequency while maintaining a low die temperature increases the power efficiency of an NVIDIA K20 GPU by up to 37-48% over default settings when running xGPU, a compute-bound code used in radio...

  2. Manufacturing challenges of optical current and voltage sensors for utility applications

    SciTech Connect (OSTI)

    Yakymyshyn, C.P. [Montana State Univ., Bozeman, MT (United States). Dept. of Electrical and Computer Engineering; Brubaker, M.A. [Los Alamos National Lab., NM (United States); Johnston, P.M. [Johnston (Paul M.), Raleigh, NC (United States); Reinbold, C. [ABB High Voltage Switchgear, Greensburg, PA (United States)

    1997-12-01T23:59:59.000Z

    Measurement of voltages and currents in power transmission and distribution systems are critical to the electric utility industry for both revenue metering and reliability. Nonconventional instrument transformers based on intensity modulation of optical signals have been reported in the literature for more than 20 years. Recently described devices using passive bulk optical sensor elements include the Electro-Optic Voltage Transducer (EOVT) and Magneto-Optic Current Transducer (MOCT). These technologies offer substantial advantages over conventional instrument transformers in accuracy, optical isolation bandwidth, environmental compatibility, weight and size. This paper describes design and manufacturing issues associated with the EOVT and the Optical Metering Unit (OMU) recently introduced by ABB with field installation results presented for prototype units in the 345 kV and 420 kV voltage classes. The OMU incorporates an EOVT and MOCT to monitor the voltage and current on power transmission lines using a single free-standing device.

  3. A Thermally-Aware Methodology for Design-Specific Optimization of Supply and Threshold Voltages in Nanometer Scale ICs

    E-Print Network [OSTI]

    411 A Thermally-Aware Methodology for Design-Specific Optimization of Supply and Threshold Voltages and associated thermal effects have strong impact on the packaging, cooling costs, and reliability for deep submicron technologies [2-5]. For power-constrained applications, lowering supply voltage (Vdd) offers

  4. Abstract--This paper investigates how to detect a dynamic voltage collapse situation. The generator and governor dynamics

    E-Print Network [OSTI]

    to an interest in maintaining an optimum, secure and reliable power system operation. One such security issue of the index during the line loss, slow increasing loading and step loading situations. The paper also brings simulations and investigation. Index Terms-- Voltage stability, dynamic voltage collapse, EUROSTAG, security

  5. DECENTRALIZED VOLTAGE CONTROL TO MINIMIZE DISTRIBUTION LOSSES IN AN ISLANDED MICROGRID

    E-Print Network [OSTI]

    Peng, Huei

    to deploy renewable energy sources such as solar and wind to reduce reliance on fossil fuels. In addition by inverters, there may not exist any inertia at all. In such cases, regulating the grid frequency becomes power sources and energy storage systems such as batteries requires new power and voltage control

  6. High voltage transformers. (Latest citations from the INSPEC database). Published Search

    SciTech Connect (OSTI)

    NONE

    1996-02-01T23:59:59.000Z

    The bibliography contains citations concerning materials and performance of insulators used for high voltage transformers. Topics examine use of mica-fibers, gases, mica filled epoxies, and ceramics. Effects of insulation aging are reviewed, and acceptance testing of high voltage power transformers and apparatus is also examined. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  7. High voltage transformers. (Latest citations from the INSPEC database). Published Search

    SciTech Connect (OSTI)

    NONE

    1997-05-01T23:59:59.000Z

    The bibliography contains citations concerning materials and performance of insulators used for high voltage transformers. Topics examine use of mica-fibers, gases, mica filled epoxies, and ceramics. Effects of insulation aging are reviewed, and acceptance testing of high voltage power transformers and apparatus is also examined.(Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  8. (Insulating materials and large high voltage electric systems)

    SciTech Connect (OSTI)

    Dale, S.J.

    1990-09-18T23:59:59.000Z

    The traveler attended the 33rd Session of CIGRE (The International Conference on Large High Voltage Electric Systems in Paris, France) as a US technical expert advisor the Study Committee 15, Insulating Materials. Over 200 papers were discussed, contributed from over 45 countries at the conference on all aspects of electric power generation and transmission. Of special interest was a panel session on superconducting technology for electric power systems and the participation on a new task force on the electrical insulation at cryogenic temperatures. Significant insight was gained into the development of superconducting power technologies in Europe and Japan. CIGRE has set up a committee to follow the development in research on the biological effects of electric and magnetic fields. The traveler also visited the Centre for Electric Power Engineering at the University of Strathclyde, Glasgow, Scotland and discussed research on degradation of polymeric cable insulation and gas insulated equipment. 5 refs.

  9. Power Transformer Application for Wind Plant Substations

    SciTech Connect (OSTI)

    Behnke, M. R. [IEEE PES Wind Plant Collector System Design Working Group; Bloethe, W.G. [IEEE PES Wind Plant Collector System Design Working Group; Bradt, M. [IEEE PES Wind Plant Collector System Design Working Group; Brooks, C. [IEEE PES Wind Plant Collector System Design Working Group; Camm, E H [IEEE PES Wind Plant Collector System Design Working Group; Dilling, W. [IEEE PES Wind Plant Collector System Design Working Group; Goltz, B. [IEEE PES Wind Plant Collector System Design Working Group; Li, J. [IEEE PES Wind Plant Collector System Design Working Group; Niemira, J. [IEEE PES Wind Plant Collector System Design Working Group; Nuckles, K. [IEEE PES Wind Plant Collector System Design Working Group; Patino, J. [IEEE PES Wind Plant Collector System Design Working Group; Reza, M [IEEE PES Wind Plant Collector System Design Working Group; Richardson, B. [IEEE PES Wind Plant Collector System Design Working Group; Samaan, N. [IEEE PES Wind Plant Collector System Design Working Group; Schoene, Jens [IEEE PES Wind Plant Collector System Design Working Group; Smith, Travis M [ORNL; Snyder, Isabelle B [ORNL; Starke, Michael R [ORNL; Walling, R. [IEEE PES Wind Plant Collector System Design Working Group; Zahalka, G. [IEEE PES Wind Plant Collector System Design Working Group

    2010-01-01T23:59:59.000Z

    Wind power plants use power transformers to step plant output from the medium voltage of the collector system to the HV or EHV transmission system voltage. This paper discusses the application of these transformers with regard to the selection of winding configuration, MVA rating, impedance, loss evaluation, on-load tapchanger requirements, and redundancy.

  10. Development of gallium nitride power transistors

    E-Print Network [OSTI]

    Piedra, Daniel, M. Eng. Massachusetts Institute of Technology

    2011-01-01T23:59:59.000Z

    GaN-based high-voltage transistors have outstanding properties for the development of ultra-high efficiency and compact power electronics. This thesis describes a new process technology for the fabrication of GaN power ...

  11. ECE 461/2: Power Systems I Calculus and algebra

    E-Print Network [OSTI]

    Schumacher, Russ

    ECE 461/2: Power Systems I Calculus and algebra - Learns basic capabilities of PSSE AC system billing structure of the power industry - Understands basic ideas in AC system synchronism and stability - Can analyze and determine V-I in phasor form at various points in a complex power system in both

  12. Power Systems Engineering Research Center PSERC Background Paper

    E-Print Network [OSTI]

    Power Systems Engineering Research Center PSERC Background Paper What is Reactive Power? Peter W-Champaign September 16, 2003 Engineering talk Reactive power is a quantity that is normally only defined for alternating current (AC) electrical systems. Our U.S. interconnected grid is almost entirely an AC system

  13. Advanced Gate Drive for the SNS High Voltage Converter Modulator

    SciTech Connect (OSTI)

    Nguyen, M.N.; Burkhart, C.; Kemp, M.A.; /SLAC; Anderson, D.E.; /Oak Ridge

    2009-05-07T23:59:59.000Z

    SLAC National Accelerator Laboratory is developing a next generation H-bridge switch plate [1], a critical component of the SNS High Voltage Converter Modulator [2]. As part of that effort, a new IGBT gate driver has been developed. The drivers are an integral part of the switch plate, which are essential to ensuring fault-tolerant, high-performance operation of the modulator. The redesigned driver improves upon the existing gate drive in several ways. The new gate driver has improved fault detection and suppression capabilities; suppression of shoot-through and over-voltage conditions, monitoring of dI/dt and Vce(sat) for fast over-current detection and suppression, and redundant power isolation are some of the added features. In addition, triggering insertion delay is reduced by a factor of four compared to the existing driver. This paper details the design and performance of the new IGBT gate driver. A simplified schematic and description of the construction are included. The operation of the fast over-current detection circuits, active IGBT over-voltage protection circuit, shoot-through prevention circuitry, and control power isolation breakdown detection circuit are discussed.

  14. Thermally-induced voltage alteration for integrated circuit analysis

    DOE Patents [OSTI]

    Cole, Jr., Edward I. (Albuquerque, NM)

    2000-01-01T23:59:59.000Z

    A thermally-induced voltage alteration (TIVA) apparatus and method are disclosed for analyzing an integrated circuit (IC) either from a device side of the IC or through the IC substrate to locate any open-circuit or short-circuit defects therein. The TIVA apparatus uses constant-current biasing of the IC while scanning a focused laser beam over electrical conductors (i.e. a patterned metallization) in the IC to produce localized heating of the conductors. This localized heating produces a thermoelectric potential due to the Seebeck effect in any conductors with open-circuit defects and a resistance change in any conductors with short-circuit defects, both of which alter the power demand by the IC and thereby change the voltage of a source or power supply providing the constant-current biasing. By measuring the change in the supply voltage and the position of the focused and scanned laser beam over time, any open-circuit or short-circuit defects in the IC can be located and imaged. The TIVA apparatus can be formed in part from a scanning optical microscope, and has applications for qualification testing or failure analysis of ICs.

  15. Thermally-induced voltage alteration for analysis of microelectromechanical devices

    DOE Patents [OSTI]

    Walraven, Jeremy A. (Albuquerque, NM); Cole, Jr., Edward I. (Albuquerque, NM)

    2002-01-01T23:59:59.000Z

    A thermally-induced voltage alteration (TIVA) apparatus and method are disclosed for analyzing a microelectromechanical (MEM) device with or without on-board integrated circuitry. One embodiment of the TIVA apparatus uses constant-current biasing of the MEM device while scanning a focused laser beam over electrically-active members therein to produce localized heating which alters the power demand of the MEM device and thereby changes the voltage of the constant-current source. This changing voltage of the constant-current source can be measured and used in combination with the position of the focused and scanned laser beam to generate an image of any short-circuit defects in the MEM device (e.g. due to stiction or fabrication defects). In another embodiment of the TIVA apparatus, an image can be generated directly from a thermoelectric potential produced by localized laser heating at the location of any short-circuit defects in the MEM device, without any need for supplying power to the MEM device. The TIVA apparatus can be formed, in part, from a scanning optical microscope, and has applications for qualification testing or failure analysis of MEM devices.

  16. 1042 IEEE TRANSACTIONS ON COMPUTER-AIDED DESIGN OF INTEGRATED CIRCUITS AND SYSTEMS, VOL. 24, NO. 7, JULY 2005 Temperature and Supply Voltage Aware Performance

    E-Print Network [OSTI]

    He, Lei

    model with temperature and voltage scaling, and show that leakage and total energy vary by 38% and 24, JULY 2005 Temperature and Supply Voltage Aware Performance and Power Modeling at Microarchitecture Abstract--Performance and power are two primary design issues for systems ranging from server computers

  17. Group 3: Humidity, Temperature, and Voltage (Presentation)

    SciTech Connect (OSTI)

    Wohlgemuth, J.

    2013-05-01T23:59:59.000Z

    Group 3 is chartered to develop accelerated stress tests that can be used as comparative predictors of module lifetime versus stresses associated with humidity, temperature and voltage.

  18. Sacramento Area Voltage Support - Environment - Sierra Nevada...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    (SMUD), Roseville Electric (Roseville), and the California Independent System Operator (ISO) grid. Western prepared a Sacramento Voltage Support (SVS) Draft Environmental Impact...

  19. PQMII POWER QUALITY METER INSTRUCTION MANUAL 11 PQMII Power Quality Meter

    E-Print Network [OSTI]

    Meyers, Steven D.

    #12;#12;#12;PQMII POWER QUALITY METER ­ INSTRUCTION MANUAL 1­1 PQMII Power Quality Meter Chapter 1 Multilin PQMII Power Quality Meter is an ideal choice for continuous monitoring of a single or three-phase system. It provides metering for current, voltage, real power, reactive power, apparent power, energy use

  20. A study of power electronic building block (PEBB)-based integrated shipboard power systems during reconfiguration

    E-Print Network [OSTI]

    Adediran, Adeoti Taiwo

    2004-09-30T23:59:59.000Z

    concept with electric propulsion, direct current (DC) distribution, and modular technology. In the all electric ship concept, ship propulsion and ship service loads are powered by alternating current (AC) generation. For the IPS, power electronics...

  1. Dynamic photorefractivity guided by single-pulse voltage

    SciTech Connect (OSTI)

    Agashkov, A. V., E-mail: agashkov@inel.bas.net.by; Kovalev, A. A. [National Academy of Sciences of Belarus, Institute of Electronics (Belarus); Parka, J. [Military University of Technology, Institute of Applied Physics (Poland)

    2008-03-15T23:59:59.000Z

    The dynamic photorefractivity in a cell with photoconducting orienting layers, filled with a nematic liquid crystal (LC) 6CHBT and a mixture of anthraquinone dyes AD1 and AD2, has been investigated. The single-pulse mode, in which the polarity and amplitude of a dc electric field applied to an LC cell are switched for a fixed time interval, has been used. The scheme of dynamic self-diffraction of low-power laser beams was used in the experiment. The dependences of the width and intensity of diffraction pulses on the bias and switching voltages have been investigated. It is established that the width and intensity of the diffraction pulse arising after initial voltage recovery depends also on the switching pulse width. At the optimal width of the control pulse, the diffraction efficiency increases by two orders of magnitude.

  2. Impact of Input Voltage Sag and Unbalance on DC Link Inductor and Capacitor Stress in Adjustable Speed Drives

    E-Print Network [OSTI]

    Lipo, Thomas

    , outages, voltage surges and sags. Power quality problems induced in adjustable-speed drives (ASDs) have (120 Hz for 60 Hz system) that increases the electrical stresses on the dc bus choke inductor (if used

  3. Sequential power-up circuit

    DOE Patents [OSTI]

    Kronberg, J.W.

    1992-06-02T23:59:59.000Z

    A sequential power-up circuit for starting several electrical load elements in series to avoid excessive current surge, comprising a voltage ramp generator and a set of voltage comparators, each comparator having a different reference voltage and interfacing with a switch that is capable of turning on one of the load elements. As the voltage rises, it passes the reference voltages one at a time and causes the switch corresponding to that voltage to turn on its load element. The ramp is turned on and off by a single switch or by a logic-level electrical signal. The ramp rate for turning on the load element is relatively slow and the rate for turning the elements off is relatively fast. Optionally, the duration of each interval of time between the turning on of the load elements is programmable. 2 figs.

  4. Systems and methods for providing power to a load based upon a control strategy

    DOE Patents [OSTI]

    Perisic, Milun; Kajouke, Lateef A; Ransom, Ray M

    2013-12-24T23:59:59.000Z

    Systems and methods are provided for an electrical system. The electrical system includes a load, an interface configured to receive a voltage from a voltage source, and a controller configured to receive the voltage from the voltage source through the interface and to provide a voltage and current to the load. Wherein, when the controller is in a constant voltage mode, the controller provides a constant voltage to the load, when the controller is in a constant current mode, the controller provides a constant current to the load, and when the controller is in a constant power mode, the controller provides a constant power to the load.

  5. Solar Electric Grid Integration- Advanced Concepts (SEGIS-AC) Funding Opportunity

    Broader source: Energy.gov [DOE]

    Through the Solar Electric Grid Integration – Advanced Concepts (SEGIS-AC) program, DOE is funding solar projects that are targeting ways to develop power electronics and build smarter, more...

  6. AC losses in type-II superconductors induced by nonuniform fluctuations of external magnetic field

    E-Print Network [OSTI]

    as the economic gains of implementation of type-II superconductors in power transmission lines, current leads amplitude. The results can be used to estimate the AC losses in flywheels, electric motors, magnetic shields

  7. Alameda-Contra Costa Transit District (AC Transit) Fuel Cell Transit Buses: Preliminary Evaluation Results

    SciTech Connect (OSTI)

    Chandler, K.; Eudy, L.

    2007-03-01T23:59:59.000Z

    This report provides an evaluation of three prototype fuel cell-powered transit buses operating at AC Transit in Oakland, California, and six baseline diesel buses similar in design to the fuel cell buses.

  8. Effects of Price-Responsive Residential Demand on Retail and Wholesale Power Market Operations

    E-Print Network [OSTI]

    Tesfatsion, Leigh

    1 Effects of Price-Responsive Residential Demand on Retail and Wholesale Power Market Operations/C) on integrated retail and wholesale power market operations. The physical operations of the A/C sys- tem at wholesale conditional on A/C load, and the retail energy prices offered to residential A/C consumers

  9. Power Droop Testing Ilia Polian1

    E-Print Network [OSTI]

    Polian, Ilia

    Power Droop Testing Ilia Polian1 Alejandro Czutro1 Sandip Kundu2 Bernd Becker1 1 Albert sudden drop or rise in power supply voltage. This change is known as power droop and is an instance of power supply noise. Although power droop may cause an IC to fail, such failures cannot currently

  10. DYNAMIC MANAGEMENT OF POWER CONSUMPTION Tajana Simunic

    E-Print Network [OSTI]

    Simunic, Tajana

    Chapter 1 DYNAMIC MANAGEMENT OF POWER CONSUMPTION Tajana Simunic HP Labs Abstract Power consumption by adapting to changes in environment are proposed: dynamic power management and dynamic voltage scaling. Dynamic power management (DPM) algorithms aim to reduce the power consumption at the system level

  11. www.eprg.group.cam.ac.uk EPRGWORKINGPAPER

    E-Print Network [OSTI]

    Aickelin, Uwe

    wind power, long-term contracts, balancing costs JEL Classification Q42, L14, L94 Contact dmgn. The estimated extra trading and balancing costs of a CfD for on-shore wind might be Ł70 million/yr by 2020www.eprg.group.cam.ac.uk EPRGWORKINGPAPER Abstract Contracting for wind generation EPRG Working

  12. This manuscript downloaded from www.microgrids.et.aau.dk is the preprint of the final paper: L. Meng, F. Tang, M. Savaghebi, J. C. Vasquez, and J. M. Guerrero, "Tertiary control of voltage unbalance compensation for optimal power quality in

    E-Print Network [OSTI]

    Vasquez, Juan Carlos

    distributed generators (DGs) equally share the compensation efforts. Tertiary control, which inherently in a multi-bus islanded system by optimally utilizing DGs as distributed compensators and saves. DG Distributed generation. E0 Rated voltage amplitude. E* Reference of voltage amplitude. fc Cut

  13. Voltage regulation in linear induction accelerators

    DOE Patents [OSTI]

    Parsons, William M. (Santa Fe, NM)

    1992-01-01T23:59:59.000Z

    Improvement in voltage regulation in a Linear Induction Accelerator wherein a varistor, such as a metal oxide varistor, is placed in parallel with the beam accelerating cavity and the magnetic core. The non-linear properties of the varistor result in a more stable voltage across the beam accelerating cavity than with a conventional compensating resistance.

  14. Voltage regulation in linear induction accelerators

    DOE Patents [OSTI]

    Parsons, W.M.

    1992-12-29T23:59:59.000Z

    Improvement in voltage regulation in a linear induction accelerator wherein a varistor, such as a metal oxide varistor, is placed in parallel with the beam accelerating cavity and the magnetic core is disclosed. The non-linear properties of the varistor result in a more stable voltage across the beam accelerating cavity than with a conventional compensating resistance. 4 figs.

  15. Designing of Hybrid Power Generation System using Wind energy- Photovoltaic Solar energy- Solar energy with Nanoantenna

    E-Print Network [OSTI]

    All the natural wastage energies are used for production of Electricity. Thus, the Electrical Power or Electricity is available with a minimum cost and pollution free to anywhere in the world at all times. This process reveals a unique step in electricity generation and availability from natural resources without hampering the ecological balance. This paper describes a new and evolving Electrical Power Generation System by integrating simultaneously photovoltaic Solar Energy, solar Energy with Nano-antenna, Wind Energy and non conventional energy sources. We can have an uninterrupted power supply irrespective of the natural condition without any sort of environmental pollution. Moreover this process yields the least production cost for electricity generation. Utilization of lightning energy for generation of electricity reveals a new step. The set-up consists of combination of photo-voltaic solar-cell array & Nano-anteena array, a mast mounted wind generator, lead-acid storage batteries, an inverter unit to convert DC power to AC power, electrical lighting loads and electrical heating loads, several fuse and junction boxes and associated wiring, and test instruments for measuring voltages, currents, power factors, and harmonic contamination data throughout the system. This hybrid solar-wind power generating system will extensively use in the Industries and also in external use like home appliance.

  16. Interleaved power converter

    DOE Patents [OSTI]

    Zhu, Lizhi (Canton, MI)

    2007-11-13T23:59:59.000Z

    A power converter architecture interleaves full bridge converters to alleviate thermal management problems in high current applications, and may, for example, double the output power capability while reducing parts count and costs. For example, one phase of a three phase inverter is shared between two transformers, which provide power to a rectifier such as a current doubler rectifier to provide two full bridge DC/DC converters with three rather than four high voltage inverter legs.

  17. Development of an AC Module System: Final Technical Report

    SciTech Connect (OSTI)

    Suparna Kadam; Miles Russell

    2012-06-15T23:59:59.000Z

    The GreenRay Inc. program focused on simplifying solar electricity and making it affordable and accessible to the mainstream population. This was accomplished by integrating a solar module, micro-inverter, mounting and monitoring into a reliable, 'plug and play' AC system for residential rooftops, offering the following advantages: (1) Reduced Cost: Reduction in installation labor with fewer components, faster mounting, faster wiring. (2) Maximized Energy Production: Each AC Module operates at its maximum, reducing overall losses from shading, mismatch, or module downtime. (3) Increased Safety. Electrical and fire safety experts agree that AC Modules have significant benefits, with no energized wiring or live connections during installation, maintenance or emergency conditions. (4) Simplified PV for a Broader Group of Installers. Dramatic simplification of design and installation of a solar power system, enabling faster and more efficient delivery of the product into the market through well-established, mainstream channels. This makes solar more accessible to the public. (5) Broadened the Rooftop Market: AC Modules enable solar for many homes that have shading, split roofs, or obstructions. In addition, due to the smaller building block size of 200W vs. 1000W, homeowners with budget limitations can start small and add to their systems over time. Through this DOE program GreenRay developed the all-in-one AC Module system with an integrated PV Module and microinverter, custom residential mounting and performance monitoring. Development efforts took the product from its initial concept, through prototypes, to a commercial product sold and deployed in the residential market. This pilot deployment has demonstrated the technical effectiveness of the AC Module system in meeting the needs and solving the problems of the residential market. While more expensive than the traditional central inverter systems at the pilot scale, the economics of AC Modules become more and more favorable as the product matures and is made in high volumes. GreenRay's early customers have been highly enthusiastic about the AC Module system benefits.

  18. IEEE TRANSACTIONS ON POWER SYSTEMS, VOL. 16, NO. 3, AUGUST 2001 427 Direct Assessment of Protection Operation and

    E-Print Network [OSTI]

    Hiskens, Ian A.

    and islanding; · voltage dips, which may cause motors to stall, contac- tors to open, and power electronic

  19. Probing spin entanglement by gate-voltage-controlled interference of current correlation in quantum spin Hall insulators

    E-Print Network [OSTI]

    Wei Chen; Z. D. Wang; R. Shen; D. Y. Xing

    2014-05-21T23:59:59.000Z

    We propose an entanglement detector composed of two quantum spin Hall insulators and a side gate deposited on one of the edge channels. For an ac gate voltage, the differential noise contributed from the entangled electron pairs exhibits the nontrivial step structures, from which the spin entanglement concurrence can be easily obtained. The possible spin dephasing effects in the quantum spin Hall insulators are also included.

  20. Flexible method for monitoring fuel cell voltage

    DOE Patents [OSTI]

    Mowery, Kenneth D. (Noblesville, IN); Ripley, Eugene V. (Russiaville, IN)

    2002-01-01T23:59:59.000Z

    A method for equalizing the measured voltage of each cluster in a fuel cell stack wherein at least one of the clusters has a different number of cells than the identical number of cells in the remaining clusters by creating a pseudo voltage for the different cell numbered cluster. The average cell voltage of the all of the cells in the fuel cell stack is calculated and multiplied by a constant equal to the difference in the number of cells in the identical cell clusters and the number of cells in the different numbered cell cluster. The resultant product is added to the actual voltage measured across the different numbered cell cluster to create a pseudo voltage which is equivalent in cell number to the number of cells in the other identical numbered cell clusters.

  1. A Guidebook on Grid Interconnection and Islanded Operation of Mini-Grid Power Systems Up to 200 kW

    E-Print Network [OSTI]

    Greacen, Chris

    2014-01-01T23:59:59.000Z

    are waived for solar projects that do not sell power to thethat convert DC power to AC. Since solar PV modules produce

  2. Sensorless Direct Torque Control For Salient Pole PMSM Based on Extended Kalman Filter Fed By AC/DC/AC Converter

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Sensorless Direct Torque Control For Salient ­ Pole PMSM Based on Extended Kalman Filter Fed By AC is proposed. The Direct Torque Control (DTC) technique for PMSM is receiving increasing attention due on the stochastic intromission, in others words, noise. The PMSM is fed by an indirect power electronic converter

  3. Variable Frequency AC Drives for Cooling Tower Energy Efficiency

    E-Print Network [OSTI]

    Corey, R. W.

    1982-01-01T23:59:59.000Z

    speed fan drives. Fan speed is reduced to yield specific water temperatures at thermal conditions less difficult than design. The reduced air flow is accomplished by reduced fan power consumption, resulting in optimum cooling tower operation... and economics. Automatic fan speed control by sensing cold water temperature is the economic essence of the application of adjustable frequency power to A-C fan motors. 2.2 Cell Partitions In some multi-cell mechanical-draft cooling towers, the isolation...

  4. ACS | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:Ezfeedflag JumpID-fTriWildcat 1 WindtheEnergySulfonate as aAAB AsiaABEEolicaSection Logo:ACS

  5. ACS Symposium Program

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del(ANL-IN-03-032)8Li (59AJ76) (See the EnergyTAMANG, APIL. A Multilevel224th ACS

  6. Wide-range voltage modulation

    SciTech Connect (OSTI)

    Rust, K.R.; Wilson, J.M.

    1992-06-01T23:59:59.000Z

    The Superconducting Super Collider`s Medium Energy Booster Abort (MEBA) kicker modulator will supply a current pulse to the abort magnets which deflect the proton beam from the MEB ring into a designated beam stop. The abort kicker will be used extensively during testing of the Low Energy Booster (LEB) and the MEB rings. When the Collider is in full operation, the MEBA kicker modulator will abort the MEB beam in the event of a malfunction during the filling process. The modulator must generate a 14-{mu}s wide pulse with a rise time of less than 1 {mu}s, including the delay and jitter times. It must also be able to deliver a current pulse to the magnet proportional to the beam energy at any time during ramp-up of the accelerator. Tracking the beam energy, which increases from 12 GeV at injection to 200 GeV at extraction, requires the modulator to operate over a wide range of voltages (4 kV to 80 kV). A vacuum spark gap and a thyratron have been chosen for test and evaluation as candidate switches for the abort modulator. Modulator design, switching time delay, jitter and pre-fire data are presented.

  7. Hybrid Electric Vehicle Power Management Solutions Based on Isolated and Non-Isolated Configurations of MMCCC Converter

    SciTech Connect (OSTI)

    Khan, Faisal H [ORNL; Tolbert, Leon M [ORNL; Webb, William E [Oak Ridge National Laboratory (ORNL)

    2009-01-01T23:59:59.000Z

    This paper presents the various configurations of a multilevel modular capacitor-clamped converter (MMCCC), and it reveals many useful and new formations of the original MMCCC for transferring power in either an isolated or nonisolated manner. The various features of the original MMCCC circuit are best suited for a multibus system in future plug-in hybrid or fuel-cell-powered vehicles' drive train. The original MMCCC is capable of bidirectional power transfer using multilevel modular structure with capacitor-clamped topology. It has a nonisolated structure, and it offers very high efficiency even at partial loads. This circuit was modified to integrate single or multiple high-frequency transformers by using the intermediate voltage nodes of the converter. On the other hand, a special formation of the MMCCC can exhibit dc outputs offering limited isolation without using any isolation transformer. This modified version can produce a high conversion ratio from a limited number of components and has several useful applications in providing power to multiple low-voltage loads in a hybrid or electric automobile. This paper will investigate the origin of generating ac outputs from the MMCCC and shows how the transformer-free version can be modified to create limited isolation from the circuit. In addition, this paper will compare various modified forms of the MMCCC topology with existing dc-dc converter circuits from compactness and component utilization perspectives.

  8. PH-315 A. La Rosa VOLTAGE-CONTROLLED OSCILLATOR

    E-Print Network [OSTI]

    PH-315 A. La Rosa VOLTAGE-CONTROLLED OSCILLATOR 1. PURPOSE: An integrator and a Schmitt Trigger voltage; hence its name "voltage-controlled oscillator." 2. VOLTAGE-CONTROLLED OSCILLATOR Figure 1 shows voltage. An unusual feature of the circuit is its operation using a single positive supply.1 #12;- + 50k V

  9. advanced filter systems: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ac transmission systems (FACTS), flywheel energy storage, high voltage dc transmission (HVDC), hypercapacitor, power electronics, supercapacitor, superconducting magnetic energy...

  10. advanced shielding systems: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ac transmission systems (FACTS), flywheel energy storage, high voltage dc transmission (HVDC), hypercapacitor, power electronics, supercapacitor, superconducting magnetic energy...

  11. advanced storage rings: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ac transmission systems (FACTS), flywheel energy storage, high voltage dc transmission (HVDC), hypercapacitor, power electronics, supercapacitor, superconducting magnetic energy...

  12. An accurate continuous calibration system for high voltage current transformer

    SciTech Connect (OSTI)

    Tong Yue; Li Binhong [College of Electrical and Electronic Engineering, Huazhong University of Science and Technology, Wuhan 430074, Hubei Province (China)

    2011-02-15T23:59:59.000Z

    A continuous calibration system for high voltage current transformers is presented in this paper. The sensor of this system is based on a kind of electronic instrument current transformer, which is a clamp-shape air core coil. This system uses an optical fiber transmission system for its signal transmission and power supply. Finally the digital integrator and fourth-order convolution window algorithm as error calculation methods are realized by the virtual instrument with a personal computer. It is found that this system can calibrate a high voltage current transformer while energized, which means avoiding a long calibrating period in the power system and the loss of power metering expense. At the same time, it has a wide dynamic range and frequency band, and it can achieve a high accuracy measurement in a complex electromagnetic field environment. The experimental results and the on-site operation results presented in the last part of the paper, prove that it can reach the 0.05 accuracy class and is easy to operate on site.

  13. Non-iterative Voltage Stability

    SciTech Connect (OSTI)

    Makarov, Yuri V.; Vyakaranam, Bharat; Hou, Zhangshuan; Wu, Di; Meng, Da; Wang, Shaobu; Elbert, Stephen T.; Miller, Laurie E.; Huang, Zhenyu

    2014-09-30T23:59:59.000Z

    This report demonstrates promising capabilities and performance characteristics of the proposed method using several power systems models. The new method will help to develop a new generation of highly efficient tools suitable for real-time parallel implementation. The ultimate benefit obtained will be early detection of system instability and prevention of system blackouts in real time.

  14. Selection of wavelets for analysis of power system disturbances

    E-Print Network [OSTI]

    Todorovic, Milos

    2002-01-01T23:59:59.000Z

    system applications . . . . . . . . . . . . . . 4 C. Summary, . 7 II WAVELET TRANSFORM . A. Introduction . . B. Wavelet transform and multiresolution analysis . . . C. Characteristic properties of wavelets. D. Summary . . . . . . . . 8... algorithm. . . . . . . I 3 3. Two-channel perfect reconstruction filter . . . 14 4. Typical voltage swell waveform. . . . . . . 22 5. Typical voltage sag waveform. . . . . 24 6. Typical voltage transinet disturbance waveform . . 7. Typical power...

  15. Alliant Energy (Wisconsin Power and Light) - Farm Wiring Financing...

    Broader source: Energy.gov (indexed) [DOE]

    Power and Light) offers a farm wiring financing program to increase farm safety, productivity and efficiency, while decreasing the potential for stray voltage on livestock...

  16. Fault-tolerant Partial-resonant High-frequency AC-link Converters and Their Applications

    E-Print Network [OSTI]

    Keyhani, Hamidreza

    2014-01-08T23:59:59.000Z

    concerns in addition to voltage and current scalabilities. Moreover, fault tolerance of power converters is becoming more and more essential in many applications, such as aerospace and subsea systems. Fault tolerance involves the detection...

  17. Solid State AC Motor Drives - Conservation Perspectives

    E-Print Network [OSTI]

    Mohan, N.; Ferraro, R. J.

    1982-01-01T23:59:59.000Z

    sources of electromagnetic interference and their wid~spread use may result in interference with the ne~rby com munication circuits and Power Line Communi?ations (PLC ). EPRI ACTIVITIES RE: HARMONICS The study of harmonics and electrical noise... generated by solid-state control devices ~s been underway at EPRI since the mid 1970's. A ~ecent EPRI project (6) investigated the techniqubs to minimize the generation of harmonics and t~e effects of current and voltage surges on the utili~y distri...

  18. HIGH VOLTAGE TERMINAL IN COSY ELECTRON COOLER V.A. Chekavinskiy, E.A. Bekhtenev, I.A. Gusev, M.N. Kondaurov, V.R. Kozak, E.A. Kuper, V.R.

    E-Print Network [OSTI]

    Kozak, Victor R.

    HIGH VOLTAGE TERMINAL IN COSY ELECTRON COOLER V.A. Chekavinskiy, E.A. Bekhtenev, I.A. Gusev, M acceleration system ­ high voltage terminal. All power and control electronics were placed in a single isolated Voltage Terminal (HVT) in electron cooler is intended for generating of electron cooling beam

  19. Electro-optical voltage sensor head

    DOE Patents [OSTI]

    Woods, Gregory K. (Idaho Falls, ID)

    1998-01-01T23:59:59.000Z

    A miniature electro-optic voltage sensor system capable of accurate operation at high voltages. The system employs a transmitter, a sensor disposed adjacent to but out of direct electrical contact with a conductor on which the voltage is to be measured, a detector, and a signal processor. The transmitter produces a beam of electromagnetic radiation which is routed into the sensor where the beam undergoes the Pockels electro-optic effect. The electro-optic effect causes phase shifting in the beam, which is in turn converted to a pair of independent beams, from which the voltage of a system based on its E-field is determined when the two beams are normalized by the signal processor. The sensor converts the beam by splitting the beam in accordance with the axes of the beam's polarization state (an ellipse whose ellipticity varies between -1 and +1 in proportion to voltage) into at least two AM signals. These AM signals are fed into a signal processor and processed to determine the voltage between a ground conductor and the conductor on which voltage is being measured.

  20. Voltage Collapse Margin Sensitivity Methods applied to the Power System

    E-Print Network [OSTI]

    Greene Ian Dobson Electrical & Computer Engineering Department University of Wisconsin-Madison 1415 Outages causing at least 75 MW reduction in loading margin . . . . . . . . . . . . . . . . . . . . . . . . . . 24 4.2 Radial Line Outages . . . . . . . . . . . . . . . . . . . . . . . 24 4.3 Non-radial Line

  1. Fiber optic current monitor for high-voltage applications

    DOE Patents [OSTI]

    Renda, G.F.

    1992-04-21T23:59:59.000Z

    A current monitor which derives its power from the conductor being measured for bidirectionally measuring the magnitude of current (from DC to above 50 khz) flowing through a conductor across which a relatively high level DC voltage is applied, includes a pair of identical transmitter modules connected in opposite polarity to one another in series with the conductor being monitored, for producing from one module a first light signal having an intensity directly proportional to the magnitude of current flowing in one direction through the conductor during one period of time, and from the other module a second light signal having an intensity directly proportional to the magnitude of current flowing in the opposite direction through the conductor during another period of time, and a receiver located in a safe area remote from the high voltage area for receiving the first and second light signals, and converting the same to first and second voltage signals having levels indicative of the magnitude of current being measured at a given time. 6 figs.

  2. Induction of nuclear fission by high-voltage application

    E-Print Network [OSTI]

    Hirokazu Maruyama

    2007-11-20T23:59:59.000Z

    In nuclear power generation, fissile materials are mainly used. For example, $U^{235}$ is fissile and therefore quite essential for use of nuclear energy. However, the material $U^{235}$ has very small natural abundance less than 1 %. We should seek possibility of utilizing fissionable materials such as $U^{238}$ because natural abundance of such fissionable materials is generally much larger than fissile ones. In this paper, we show that thermal neutrons with vanishing kinetic energy can induce nuclear fission when high voltage is applied to fissionable materials. To obtain this result, we use the liquid-drop model for nuclei. Finally, we propose how fissionable materials can be utilized.

  3. ADEPT: Efficient Power Conversion

    SciTech Connect (OSTI)

    None

    2011-01-01T23:59:59.000Z

    ADEPT Project: In today’s increasingly electrified world, power conversion—the process of converting electricity between different currents, voltage levels, and frequencies—forms a vital link between the electronic devices we use every day and the sources of power required to run them. The 14 projects that make up ARPA-E’s ADEPT Project, short for “Agile Delivery of Electrical Power Technology,” are paving the way for more energy efficient power conversion and advancing the basic building blocks of power conversion: circuits, transistors, inductors, transformers, and capacitors.

  4. ProspectusofCPESMiniConsortiumon PowerManagement(PMC)

    E-Print Network [OSTI]

    Virginia Tech

    on developing precompetitive technologies in the areas of power management for distributed power system architectures, power management, EMI/EMC, power quality, Ac/Dc converters, Dc/Dc converters, POL, more power is consumed by both active and standby systems. Consequently, efficient power management

  5. Dynamic Power Management with Power Network-on-Chip Inna Vaisband and Eby G. Friedman

    E-Print Network [OSTI]

    Friedman, Eby G.

    Dynamic Power Management with Power Network-on-Chip Inna Vaisband and Eby G. Friedman Department dynamically controlled power to support power efficient and portable systems. Effi- ciently providing multiple point-of-load on-chip voltages requires fundamental changes to the power delivery and management process

  6. PowerPoint Presentation

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    NREL , Golden, CO, Rep. NREL CP-520-37358, 2005. Solar Resource Calendar - 1MW AC Output Power December 2011 at 1MW PV site in Tennessee 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16...

  7. Current-voltage relation for a field ionizing He beam detector

    SciTech Connect (OSTI)

    DePonte, D. P. [Physics Department, Arizona State University, Tempe, Arizona 85281 (United States); Elliott, Greg S. [Physics Department, University of Puget Sound, Tacoma, Washington, D.C. 98416 (United States); Kevan, S. D. [Physics Department, University of Oregon, Eugene, Oregon 97403-1274 (United States)

    2009-02-15T23:59:59.000Z

    Emerging interest in utilizing the transverse coherence properties of thermal energy atomic and molecular beams motivates the development of ionization detectors with near unit detection efficiency and adequate spatial resolution to resolve interference fringes of submicron dimension. We demonstrate that a field ionization tip coupled to a charged particle detector meets these requirements. We have systematically studied the current-voltage relationship for field ionization of helium using tungsten tips in diffuse gas and in a supersonic helium beam. For all 16 tips used in this study, the dependence of ion current on voltage for tips of fixed radius was found to differ from that for tips held at constant surface electric field. A scaling analysis is presented to explain this difference. Ion current increased on average to the 2.8 power of voltage for a tip at fixed field and approximately fifth power of voltage for fixed radius for a liquid nitrogen cooled tip in room temperature helium gas. For the helium beam, ion current increased as 2.2 power of voltage with constant surface field. The capture region of the tips was found to be up to 0.1 {mu}m{sup 2} for diffuse gas and 0.02 {mu}m{sup 2} in the beam. Velocity dependence and orientation of tip to beam were also studied.

  8. Design concepts for a pulse power test facility to simulate EMP surges. Part II. Slow pulses

    SciTech Connect (OSTI)

    Dethlefsen, R.

    1985-10-01T23:59:59.000Z

    The work described in this report was sponsored by the Division of Electric Energy Systems (EES) of the US Department of Energy (DOE) through a subcontract with the Power Systems Technology Program at the Oak Ridge National Laboratory (ORNL). The work deals with the effect of high altitude nuclear bursts on electric power systems. In addition to fast voltage transients, slow, quasi-dc currents are also induced into extended power systems with grounded neutral connections. Similar phenomena at lower magnitude are generated by solar induced electromagnetic pulses (EMP). These have caused power outages, related to solar storms, at northern latitudes. The applicable utility experience is reviewed in order to formulate an optimum approach to future testing. From a wide variety of options two pulser designs were selected as most practical, a transformer-rectifier power supply, and a lead acid battery pulser. both can be mounted on a trailer as required for field testing on utility systems. The battery system results in the least cost. Testing on power systems requires that the dc pulser pass high values of alternating current, resulting from neutral imbalance or from potential fault currents. Batteries have a high ability to pass alternating currents. Most other pulser options must be protected by an ac bypass in the form of an expensive capacitor bank. 8D truck batteries can meet the original specification of 1 kA test current. Improved batteries for higher discharge currents are available.

  9. Superconducting shielded core reactor with reduced AC losses

    DOE Patents [OSTI]

    Cha, Yung S.; Hull, John R.

    2006-04-04T23:59:59.000Z

    A superconducting shielded core reactor (SSCR) operates as a passive device for limiting excessive AC current in a circuit operating at a high power level under a fault condition such as shorting. The SSCR includes a ferromagnetic core which may be either closed or open (with an air gap) and extends into and through a superconducting tube or superconducting rings arranged in a stacked array. First and second series connected copper coils each disposed about a portion of the iron core are connected to the circuit to be protected and are respectively wound inside and outside of the superconducting tube or rings. A large impedance is inserted into the circuit by the core when the shielding capability of the superconducting arrangement is exceeded by the applied magnetic field generated by the two coils under a fault condition to limit the AC current in the circuit. The proposed SSCR also affords reduced AC loss compared to conventional SSCRs under continuous normal operation.

  10. Voltage Management of Networks with Distributed Generation. 

    E-Print Network [OSTI]

    O'Donnell, James

    2008-01-01T23:59:59.000Z

    At present there is much debate about the impacts and benefits of increasing the amount of generation connected to the low voltage areas of the electricity distribution network. The UK government is under political ...

  11. Electro-optic high voltage sensor

    DOE Patents [OSTI]

    Davidson, James R.; Seifert, Gary D.

    2003-09-16T23:59:59.000Z

    A small sized electro-optic voltage sensor capable of accurate measurement of high voltages without contact with a conductor or voltage source is provided. When placed in the presence of an electric field, the sensor receives an input beam of electromagnetic radiation. A polarization beam displacer separates the input beam into two beams with orthogonal linear polarizations and causes one linearly polarized beam to impinge a crystal at a desired angle independent of temperature. The Pockels effect elliptically polarizes the beam as it travels through the crystal. A reflector redirects the beam back through the crystal and the beam displacer. On the return path, the polarization beam displacer separates the elliptically polarized beam into two output beams of orthogonal linear polarization. The system may include a detector for converting the output beams into electrical signals and a signal processor for determining the voltage based on an analysis of the output beams.

  12. Low voltage arc formation in railguns

    DOE Patents [OSTI]

    Hawke, R.S.

    1987-11-17T23:59:59.000Z

    A low voltage plasma arc is first established across the rails behind the projectile by switching a low voltage high current source across the rails to establish a plasma arc by vaporizing a fuse mounted on the back of the projectile, maintaining the voltage across the rails below the railgun breakdown voltage to prevent arc formation ahead of the projectile. After the plasma arc has been formed behind the projectile a discriminator switches the full energy bank across the rails to accelerate the projectile. A gas gun injector may be utilized to inject a projectile into the breech of a railgun. The invention permits the use of a gas gun or gun powder injector and an evacuated barrel without the risk of spurious arc formation in front of the projectile. 2 figs.

  13. Low voltage arc formation in railguns

    DOE Patents [OSTI]

    Hawke, Ronald S. (Livermore, CA)

    1987-01-01T23:59:59.000Z

    A low voltage plasma arc is first established across the rails behind the projectile by switching a low voltage high current source across the rails to establish a plasma arc by vaporizing a fuse mounted on the back of the projectile, maintaining the voltage across the rails below the railgun breakdown voltage to prevent arc formation ahead of the projectile. After the plasma arc has been formed behind the projectile a discriminator switches the full energy bank across the rails to accelerate the projectile. A gas gun injector may be utilized to inject a projectile into the breech of a railgun. The invention permits the use of a gas gun or gun powder injector and an evacuated barrel without the risk of spurious arc formation in front of the projectile.

  14. Low voltage arc formation in railguns

    DOE Patents [OSTI]

    Hawke, R.S.

    1985-08-05T23:59:59.000Z

    A low voltage plasma arc is first established across the rails behind the projectile by switching a low voltage high current source across the rails to establish a plasma arc by vaporizing a fuse mounted on the back of the projectile, maintaining the voltage across the rails below the railgun breakdown voltage to prevent arc formation ahead of the projectile. After the plasma arc has been formed behind the projectile a discriminator switches the full energy bank across the rails to accelerate the projectile. A gas gun injector may be utilized to inject a projectile into the breech of a railgun. The invention permits the use of a gas gun or gun powder injector and an evacuated barrel without the risk of spurious arc formation in front of the projectile.

  15. High-Voltage Solid Polymer Batteries for Electric Drive Vehicles...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    High-Voltage Solid Polymer Batteries for Electric Drive Vehicles High-Voltage Solid Polymer Batteries for Electric Drive Vehicles 2012 DOE Hydrogen and Fuel Cells Program and...

  16. Addressing the Voltage Fade Issue with Lithium-Manganese-Rich...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Addressing the Voltage Fade Issue with Lithium-Manganese-Rich Oxide Cathode Materials Addressing the Voltage Fade Issue with Lithium-Manganese-Rich Oxide Cathode Materials 2013 DOE...

  17. Addressing the Voltage Fade Issue with Lithium-Manganese-Rich...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Voltage Fade Issue with Lithium-Manganese-Rich Oxide Cathode Materials Addressing the Voltage Fade Issue with Lithium-Manganese-Rich Oxide Cathode Materials 2012 DOE Hydrogen and...

  18. Constant voltage electro-slag remelting control

    DOE Patents [OSTI]

    Schlienger, M.E.

    1996-10-22T23:59:59.000Z

    A system for controlling electrode gap in an electro-slag remelt furnace has a constant regulated voltage and an electrode which is fed into the slag pool at a constant rate. The impedance of the circuit through the slag pool is directly proportional to the gap distance. Because of the constant voltage, the system current changes are inversely proportional to changes in gap. This negative feedback causes the gap to remain stable. 1 fig.

  19. Spark gap with low breakdown voltage jitter

    DOE Patents [OSTI]

    Rohwein, Gerald J. (Albuquerque, NM); Roose, Lars D. (Albuquerque, NM)

    1996-01-01T23:59:59.000Z

    Novel spark gap devices and electrodes are disclosed. The novel spark gap devices and electrodes are suitable for use in a variety of spark gap device applications. The shape of the electrodes gives rise to local field enhancements and reduces breakdown voltage jitter. Breakdown voltage jitter of approximately 5% has been measured in spark gaps according the invention. Novel electrode geometries and materials are disclosed.

  20. Spark gap with low breakdown voltage jitter

    DOE Patents [OSTI]

    Rohwein, G.J.; Roose, L.D.

    1996-04-23T23:59:59.000Z

    Novel spark gap devices and electrodes are disclosed. The novel spark gap devices and electrodes are suitable for use in a variety of spark gap device applications. The shape of the electrodes gives rise to local field enhancements and reduces breakdown voltage jitter. Breakdown voltage jitter of approximately 5% has been measured in spark gaps according the invention. Novel electrode geometries and materials are disclosed. 13 figs.