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1

High frequency breakdown voltage  

SciTech Connect

This report contains information about the effect of frequency on the breakdown voltage of an air gap at standard pressure and temperature, 76 mm Hg and O{degrees}C, respectively. The frequencies of interest are 47 MHz and 60 MHz. Additionally, the breakdown in vacuum is briefly considered. The breakdown mechanism is explained on the basis of collision and ionization. The presence of the positive ions produced by ionization enhances the field in the gap, and thus determines the breakdown. When a low-frequency voltage is applied across the gap, the breakdown mechanism is the same as that caused by the DC or static voltage. However, when the frequency exceeds the first critical value f{sub c}, the positive ions are trapped in the gap, increasing the field considerably. This makes the breakdown occur earlier; in other words, the breakdown voltage is lowered. As the frequency increases two decades or more, the second critical frequency, f{sub ce}, is reached. This time the electrons start being trapped in the gap. Those electrons that travel multiple times across the gap before reaching the positive electrode result in an enormous number of electrons and positive ions being present in the gap. The result is a further decrease of the breakdown voltage. However, increasing the frequency does not decrease the breakdown voltage correspondingly. In fact, the associated breakdown field intensity is almost constant (about 29 kV/cm).The reason is that the recombination rate increases and counterbalances the production rate, thus reducing the effect of the positive ions` concentration in the gap. The theory of collision and ionization does not apply to the breakdown in vacuum. It seems that the breakdown in vacuum is primarily determined by the irregularities on the surfaces of the electrodes. Therefore, the effect of frequency on the breakdown, if any, is of secondary importance.

Chu, Thanh Duy

1992-03-01T23:59:59.000Z

2

Quartz crystal microbalance based on passive frequency to voltage converter  

SciTech Connect

In dynamics of evaporation or drying of microdrops from a solid surface, a faster and precise quartz crystal microbalance (QCM) is needed. The fast QCM based on frequency to voltage converter is an attractive and powerful tool in the investigation of the dynamic regime of evaporation to translate the frequency shift in terms of a continuous voltage change. The frequency shift monitoring in fast QCM applications is a real challenge for electronic processing interface. Originally developed as a frequency shift processing interface, this novel passive frequency to voltage converter can produce faster, stable, and accurate results in regard to the QCM sensor behavior. In this article, the concept and circuit of passive frequency to voltage converter will be explained followed by static and dynamic characterization. Experimental results of microdrops evaporation will be given.

Burda, Ioan; Tunyagi, Arthur [Department of Physics, Babes-Bolyai University, Cluj-Napoca, 400084 (Romania)

2012-02-15T23:59:59.000Z

3

Rank based dynamic voltage and frequency scaling fortiled graphics processors  

Science Conference Proceedings (OSTI)

With increasing interest in sophisticated graphics capabilities in mobile systems, energy consumption of graphics hardware is becoming a major design concern in addition to the traditional performance enhancement criteria. Our study of various modern ... Keywords: dynamic voltage and frequency scaling, graphics processor, low power, workload prediction

B.V.N Silpa; Gummidipudi Krishnaiah; Preeti Ranjan Panda

2010-10-01T23:59:59.000Z

4

Theory and practice of dynamic voltage/frequency scaling in the high performance computing environment.  

E-Print Network (OSTI)

?? This dissertation provides a comprehensive overview of the theory and practice of Dynamic Voltage/Frequency Scaling (DVFS) in the High Performance Computing (HPC) environment. We… (more)

Rountree, Barry Louis

2010-01-01T23:59:59.000Z

5

Theory and Practice of Dynamic Voltage/Frequency Scaling in the High Performance Computing Environment .  

E-Print Network (OSTI)

??This dissertation provides a comprehensive overview of the theory and practice of Dynamic Voltage/Frequency Scaling (DVFS) in the High Performance Computing (HPC) environment. We summarize… (more)

Rountree, Barry

2009-01-01T23:59:59.000Z

6

Radio-Frequency Interference (RFI) From Extra-High- Voltage (EHV) Transmission Lines  

E-Print Network (OSTI)

The subject of radio-frequency interference (RFI) generated by high-voltage transmission lines has long been of both academic and commercial interest because of concerns about

Patrick C. Crane

2010-01-01T23:59:59.000Z

7

Energy Aware Dynamic Voltage and Frequency Selection for Real-Time Systems with Energy Harvesting  

E-Print Network (OSTI)

Energy Aware Dynamic Voltage and Frequency Selection for Real-Time Systems with Energy Harvesting}@binghamton.edu Abstract In this paper, an energy aware dynamic voltage and frequency selection (EA-DVFS) algorithm energy and the harvested energy in a future duration. Specifically, if the system has sufficient energy

Qiu, Qinru

8

Cooperative frequency control with a multi-terminal high-voltage DC network  

Science Conference Proceedings (OSTI)

We consider frequency control in power systems made of several non-synchronous AC areas connected by a multi-terminal high-voltage direct current (HVDC) grid. We propose two HVDC control schemes to make the areas collectively react to power imbalances, ... Keywords: Decentralized control, Frequency control, HVDC systems, Power system control

Alain Sarlette; Jing Dai; Yannick Phulpin; Damien Ernst

2012-12-01T23:59:59.000Z

9

Variable speed constant frequency constant voltage alternator. Annual report  

DOE Green Energy (OSTI)

A test alternator is operated with digital control of its output frequency for variable shaft speed. The machine is a two-pole alternator with power removed through slip rings. The output frequency of the alternator is controlled by rotating the field by stepping through sixteen coils around the rotor. Usually four coils are active at one time. The rotating field in the stationary coils of the stator is controlled by microcircuits. The control circuits are constructed with available low-cost, low-power integrated circuits (ICs). The test results from the first test alternator indicate the feasibility of using this type of alternator to convert available wind power directly to usable 60 hertz power.

Grannemann, W.W.; Yang, C.E.; Seo, P.H.

1980-07-01T23:59:59.000Z

10

Energy aware dynamic voltage and frequency selection for real-time systems with energy harvesting  

Science Conference Proceedings (OSTI)

In this paper, an energy aware dynamic voltage and frequency selection (EA-DVFS) algorithm is proposed. The EA-DVFS algorithm adjusts the processor's behavior depending on the summation of the stored energy and the harvested energy in a future duration. ...

Shaobo Liu; Qinru Qiu; Qing Wu

2008-03-01T23:59:59.000Z

11

PEV-Based Combined Frequency and Voltage Regulation for Smart Grid  

E-Print Network (OSTI)

PEV-Based Combined Frequency and Voltage Regulation for Smart Grid Chenye Wu, Student Member, IEEE benefit both users and utilities. Index Terms--Smart grid, plug-in electric vehicles, demand side the power grid by providing various ancillary services. In fact, recent studies have suggested that PEVs can

Wu, Chenye

12

A new measurement technique for tracking voltage phasors, local system frequency, and rate of change of frequency  

Science Conference Proceedings (OSTI)

With the advent of Substation Computer Systems dedicated to protection, control and data logging functions in a Substation, it becomes possible to develop new applications which can utilize the processing power available within the substation. The microcomputer based Symmetrical Component Distance Relay (SCDR) described in the references cited at the end of this paper possesses certain characteristics which facilitate real-time monitoring of positive sequence voltage phasor at the local power system bus. With a regression analysis the frequency and rate-of-change of frequency at the bus can also be determined from the positive sequence voltage phase angle. This paper describes the theoretical basis of these computations and describes results of experiments performed in the AEP power system simulation laboratory. Plans for future field tests on the AEP system are also outlined.

Phadke, A.G.; Adamiak, M.G.; Thorp, J.S.

1983-05-01T23:59:59.000Z

13

On the application of radio frequency voltages to ion traps via helical resonators  

E-Print Network (OSTI)

Ions confined using a Paul trap require a stable, high voltage and low noise radio frequency (RF) potential. We present a guide for the design and construction of a helical coil resonator for a desired frequency that maximises the quality factor for a set of experimental constraints. We provide an in-depth analysis of the system formed from a shielded helical coil and an ion trap by treating the system as a lumped element model. This allows us to predict the resonant frequency and quality factor in terms of the physical parameters of the resonator and the properties of the ion trap. We also compare theoretical predictions with experimental data for different resonators, and predict the voltage applied to the ion trap as a function of the Q-factor, input power and the properties of the resonant circuit.

Siverns, J D; Weidt, S; Hensinger, W K

2011-01-01T23:59:59.000Z

14

On the application of radio frequency voltages to ion traps via helical resonators  

E-Print Network (OSTI)

Ions confined using a Paul trap require a stable, high voltage and low noise radio frequency (RF) potential. We present a guide for the design and construction of a helical coil resonator for a desired frequency that maximises the quality factor for a set of experimental constraints. We provide an in-depth analysis of the system formed from a shielded helical coil and an ion trap by treating the system as a lumped element model. This allows us to predict the resonant frequency and quality factor in terms of the physical parameters of the resonator and the properties of the ion trap. We also compare theoretical predictions with experimental data for different resonators, and predict the voltage applied to the ion trap as a function of the Q-factor, input power and the properties of the resonant circuit.

J. D. Siverns; L. R. Simkins; S. Weidt; W. K. Hensinger

2011-06-24T23:59:59.000Z

15

Discovering Potential Precursors of Mammography Abnormalities based on Textual Features, Frequencies, and Sequences  

Science Conference Proceedings (OSTI)

Diagnosingbreastcancerfrommammographyreportsisheav- ily dependant on the time sequences of the patient visits. In the work described, we take a longitudinal view of the text of a patient s mam- mogram reports to explore the existence of certain phrase patterns that indicate future abnormalities may exist for the patient. Our approach uses various text analysis techniques combined with Haar wavelets for the discovery and analysis of such precursor phrase patterns. We believe the results show significant promise for the early detection of breast can- cer and other breast abnormalities.

Patton, Robert M [ORNL; Potok, Thomas E [ORNL

2010-01-01T23:59:59.000Z

16

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

DOE Patents (OSTI)

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.

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

1994-06-28T23:59:59.000Z

17

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

DOE Patents (OSTI)

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.

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

18

A Voltage Controlled Oscillator for a Phase-Locked Loop Frequency Synthesizer in a Silicon-on-Sapphire Process  

SciTech Connect

Engineers from a government-owned engineering and manufacturing facility were contracted by government-owned research laboratory to design and build an S-band telemetry transmitter using Radio Frequency Integrated Circuit (RFIC) technology packaged in a Low-Temperature Co-fired Ceramic (LTCC) Multi-Chip Module. The integrated circuit technology chosen for the Phase-Locked Loop Frequency Synthesizer portion of the telemetry transmitter was a 0.25 um CMOS process that utilizes a sapphire substrate and is fabricated by Peregrine Semiconductor corporation. This thesis work details the design of the Voltage Controlled Oscillator (VCO) portion of the PLL frequency synthesizer and constitutes an fully integrated VCO core circuit and a high-isolation buffer amplifier. The high-isolation buffer amplifier was designed to provide 16 dB of gain for 2200-3495 MHz as well as 60 dB of isolation for the oscillator core to provide immunity to frequency pulling due to RF load mismatch. Actual measurements of the amplifier gain and isolation showed the gain was approximately 5 dB lower than the simulated gain when all bond-wire and test substrate parasitics were taken into account. The isolation measurements were shown to be 28 dB at the high end of the frequency band but the measurement was more than likely compromised due to the aforementioned bond-wire and test substrate parasitics. The S-band oscillator discussed in this work was designed to operate over a frequency range of 2200 to 2300 MHz with a minimum output power of 0 dBm with a phase-noise of -92 dBc/Hz at a 100 kHz offset from the carrier. The tuning range was measured to be from 2215 MHz to 2330 MHz with a minimum output power of -7 dBm over the measured frequency range. A phase-noise of -90 dBc was measured at a 100 kHz offset from the carrier.

Garrison, Sean

2009-05-21T23:59:59.000Z

19

Experimental investigation of dielectric barrier discharge plasma actuators driven by repetitive high-voltage nanosecond pulses with dc or low frequency sinusoidal bias  

Science Conference Proceedings (OSTI)

Experimental studies were conducted of a flow induced in an initially quiescent room air by a single asymmetric dielectric barrier discharge driven by voltage waveforms consisting of repetitive nanosecond high-voltage pulses superimposed on dc or alternating sinusoidal or square-wave bias voltage. To characterize the pulses and to optimize their matching to the plasma, a numerical code for short pulse calculations with an arbitrary impedance load was developed. A new approach for nonintrusive diagnostics of plasma actuator induced flows in quiescent gas was proposed, consisting of three elements coupled together: the schlieren technique, burst mode of plasma actuator operation, and two-dimensional numerical fluid modeling. The force and heating rate calculated by a plasma model was used as an input to two-dimensional viscous flow solver to predict the time-dependent dielectric barrier discharge induced flow field. This approach allowed us to restore the entire two-dimensional unsteady plasma induced flow pattern as well as characteristics of the plasma induced force. Both the experiments and computations showed the same vortex flow structures induced by the actuator. Parametric studies of the vortices at different bias voltages, pulse polarities, peak pulse voltages, and pulse repetition rates were conducted experimentally. The significance of charge buildup on the dielectric surface was demonstrated. The charge buildup decreases the effective electric field in the plasma and reduces the plasma actuator performance. The accumulated surface charge can be removed by switching the bias polarity, which leads to a newly proposed voltage waveform consisting of high-voltage nanosecond repetitive pulses superimposed on a high-voltage low frequency sinusoidal voltage. Advantages of the new voltage waveform were demonstrated experimentally.

Opaits, Dmitry F.; Likhanskii, Alexandre V.; Neretti, Gabriele; Zaidi, Sohail; Shneider, Mikhail N.; Miles, Richard B. [Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544 (United States); Macheret, Sergey O. [Lockheed Martin Aeronautics Company, Palmdale, California 93599 (United States)

2008-08-15T23:59:59.000Z

20

CMOS implementation of a 1.6 GHz low voltage low phase noise quadrature output frequency synthesizer with automatic amplitude control  

Science Conference Proceedings (OSTI)

This article presents the design of a 1.2 V CMOS low phase noise quadrature output frequency synthesizer (FS) to be used for a GPS tuner application. Special reference is made to the design of a wide tuning range quadrature output voltage-controlled ... Keywords: AM-to-PM up-conversion, Automatic amplitude control, DC---DC Converter, Phase noise, Quadrature VCO

Owen Casha; Ivan Grech; Joseph Micallef; Edward Gatt

2008-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "voltage abnormal frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Connecting Renewables Directly to the Grid: Resilient Multi-Terminal HVDC Networks with High-Voltage High-Frequency Electronics  

SciTech Connect

GENI Project: GE is developing electricity transmission hardware that could connect distributed renewable energy sources, like wind farms, directly to the grid—eliminating the need to feed the energy generated through intermediate power conversion stations before they enter the grid. GE is using the advanced semiconductor material silicon carbide (SiC) to conduct electricity through its transmission hardware because SiC can operate at higher voltage levels than semiconductors made out of other materials. This high-voltage capability is important because electricity must be converted to high-voltage levels before it can be sent along the grid’s network of transmission lines. Power companies do this because less electricity is lost along the lines when the voltage is high.

None

2012-01-23T23:59:59.000Z

22

Optical voltage reference  

DOE Patents (OSTI)

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.

Rankin, R.; Kotter, D.

1994-04-26T23:59:59.000Z

23

Optical voltage reference  

DOE Patents (OSTI)

An optical voltage reference for providing an alternative to a battery source. 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.

Rankin, R.; Kotter, D.

1992-12-31T23:59:59.000Z

24

The frequency and voltage dependent electrical characteristics of Al-TiW-Pd2Si/n-Si structure using I-V, C-V and G/?-V measurements  

Science Conference Proceedings (OSTI)

The forward and reverse bias capacitance-voltage (C-V) and conductance-voltage (G/w-V) characteristics of Al-TiW-Pd"2Si/n-Si structures have been investigated over a wide frequency range of 5kHz-5MHz. These measurements allow to us the determination ... Keywords: 73.30.+y, 73.40.Ns, 73.40.Qv, Frequency dependent, Interface states, MS structure, Pd2Si/n-Si contacts, Series resistance

?. M. Afandiyeva; ?. Dökme; ?. Alt?ndal; L. K. Abdullayeva; Sh. G. Askerov

2008-02-01T23:59:59.000Z

25

? Adjustable Output Voltage  

E-Print Network (OSTI)

The LM25010 features all the functions needed to implement a low cost, efficient, buck regulator capable of supplying in excess of 1A load current. This high voltage regulator integrates an N-Channel Buck Switch, and is available in thermally enhanced LLP-10 and TSSOP-14EP packages. The constant on-time regulation scheme requires no loop compensation resulting in fast load transient response and simplified circuit implementation. The operating frequency remains constant with line and load variations due to the inverse relationship between the input voltage and the on-time. The valley current limit detection is set at 1.25A. Additional features include: VCC under-voltage lock-out, thermal shutdown, gate drive under-voltage lock-out, and maximum duty cycle limiter.

Lmq Is Aec-q Grade

2008-01-01T23:59:59.000Z

26

A Framework of Concurrent Task Scheduling and Dynamic Voltage and Frequency Scaling in Real-Time Embedded Systems with Energy Harvesting  

E-Print Network (OSTI)

harvesting module is comprised of a Photovoltaic (PV) panel for harvesting energy and a supercapacitor panel, state-of- charge management for the supercapacitor, and energy-harvesting- aware real-time task-leakage of the supercapacitor, and power losses in voltage converters, employs a cascaded feedback control structure

Pedram, Massoud

27

Radio Frequency Engineering, MDE, Accelerator Operations and...  

NLE Websites -- All DOE Office Websites (Extended Search)

Home Teams Low-Level Radio Frequency Magnet Power Supplies, Pulsed Power Radio Frequency, High Voltage Technologies Radio Frequency Operations CONTACTS Group Leader Dan Rees Deputy...

28

A Study of Target Frequency Bond for Frequency Control Performance Score Calculations in an Isolated System.  

E-Print Network (OSTI)

??Power system frequency is one of the key performance indices of system operation. Abnormal frequency deviations would incur negative impacts to power equipments and service… (more)

Lee, Hung-hsi

2010-01-01T23:59:59.000Z

29

PQ Encyclopedia: Understanding Voltage Unbalance  

Science Conference Proceedings (OSTI)

This PQ Encyclopedia examines voltage unbalance, methods to calculate line voltages and the degree of voltage unbalance, and mitigation techniques.

2009-12-11T23:59:59.000Z

30

HIGH VOLTAGE GENERATOR  

DOE Patents (OSTI)

This patent relates to high voltage supply circuits adapted for providing operating voltages for GeigerMueller counter tubes, and is especially directed to an arrangement for maintaining uniform voltage under changing conditions of operation. In the usual power supply arrangement for counter tubes the counter voltage is taken from across the power supply output capacitor. If the count rate exceeds the current delivering capaciiy of the capacitor, the capacitor voltage will drop, decreasing the counter voltage. The present invention provides a multivibrator which has its output voltage controlled by a signal proportional to the counting rate. As the counting rate increases beyond the current delivering capacity of the capacitor, the rectified voltage output from the multivibrator is increased to maintain uniform counter voltage.

Zito, G.V.

1959-04-21T23:59:59.000Z

31

Mitigation of different type voltage sags in low voltage distribution systems using dynamic voltage restorer  

Science Conference Proceedings (OSTI)

The main problems of the voltage sag in low voltage distribution systems due to sensitive loads. Voltage sags can caused malfunction in the distribution system. In order to protect voltage sags in the network a device which called Dynamic Voltage Restorer ... Keywords: custom device, dynamic voltage restorer (DVR), low voltage, power injected, voltage sag

Rosli Omar

2010-03-01T23:59:59.000Z

32

Substation voltage upgrading  

SciTech Connect

This report addresses specific issues to support sound yet not unduly conservative uprating practices for substations. The main parts of the report cover the insulation withstand and overvoltage protection aspects, environmental measurements, reliability criteria, and industry experience. First the insulation design concerns are addressed. Substation stress by a backflashover of the line insulation due to lightning in the vicinity of the substation is recognized as a critical stress. A representative part of a 550 kV BIL substation was erected at the EPRI High Voltage Transmission Research Center, where also a special test circuit was assembled to produce a fast front, slow tail (0.2/200 {mu}s) wave. The substation as well as some special configurations were tested for line-to-ground and line-to-line withstand. Computer studies were performed to complement the test results. A number of important conclusions was reached. The most prominent result in that the high frequency oscillations, as caused by reflections within the substation, do not effect the Critical Flashover Voltage (CFO). The present practice, based on the highest peak is therefore very conservative. The slow tail of the wave appears to dictate the CFO. An arrester model for computer studies to represent very fast as well as slow phenomena was derived. It is based on full scale arrester test data, made available in this project. The computer program to calculate arrester model parameters is also a part of the report. The electric environmental measurements are reported for the tested substation at the HVTRC and for the uprated substation of Public Service Company of Colorado, both before and after the uprating. The performance is satisfactory when corona free hardware is used. Insulation design criteria are analyzed based on substation reliability, the system viewpoint and consequences of the failure. Utility experience with uprated substations is reviewed.

Panek, J.; Elahi, H.; Lux, A.; Imece, A.F. (General Electric Co., Schenectady, NY (United States). Power Systems Engineering Dept.); LaPanse, R.A.; Stewart, J.R. (Public Service Co. of Colorado, Denver, CO (United States))

1992-04-01T23:59:59.000Z

33

Automatic voltage imbalance detector  

DOE Patents (OSTI)

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

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

1984-01-01T23:59:59.000Z

34

Constant voltage ultracapacitor  

Science Conference Proceedings (OSTI)

Ultracapacitors have attracted lots of attention recently due to their growing use in hybrid vehicles and in energy storage applications for the smart grid. A very undesirable feature of ultracapacitors is the fact that the voltage drops as the capacitor is discharged. DC-DC converters are employed at present to convert the voltage of the ultracapacitor to constant voltage; however

Ezzat G. Bakhoum

2012-01-01T23:59:59.000Z

35

Automated Voltage Standard Ready  

Science Conference Proceedings (OSTI)

... “We wanted a standard that was ... as envisioned, then within our lifetimes there will no longer be a need for voltage transfer standards that have to be ...

2013-04-08T23:59:59.000Z

36

High voltage RF feedthrough bushing  

DOE Patents (OSTI)

Described is a multi-element, high voltage radio frequency bushing for trmitting RF energy to an antenna located in a vacuum container. The bushing includes a center conductor of complex geometrical shape, an outer coaxial shield conductor, and a thin-walled hollow truncated cone insulator disposed between central and outer conductors. The shape of the center conductor, which includes a reverse curvature portion formed of a radially inwardly directed shoulder and a convex portion, controls the uniformity of the axial surface gradient on the insulator cone. The outer shield has a first substantially cylindrical portion and a second radially inwardly extending truncated cone portion.

Grotz, Glenn F. (Huntington Station, NY)

1984-01-01T23:59:59.000Z

37

A low-noise bandgap voltage reference employing dynamic element matching  

E-Print Network (OSTI)

Bandgap voltages references are widely used in IC design, but are sensitive to low-frequency noise and component mismatch. This thesis describes the design and testing of a new IC voltage reference that targets these issues ...

Herbst, Steven (Steven G.)

2011-01-01T23:59:59.000Z

38

Voltage balanced multilevel voltage source converter system  

SciTech Connect

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.

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

1997-01-01T23:59:59.000Z

39

Voltage balanced multilevel voltage source converter system  

SciTech Connect

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.

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

1997-07-01T23:59:59.000Z

40

Voltage Quality Improvement Using DVR  

Science Conference Proceedings (OSTI)

The problem of voltage sags and Swells and its severe impact on sensitive loads is well known. To solve this problem, custom power devices are used. One of those devices is the Dynamic Voltage Restorer (DVR), which is one of the most efficient and effective ... Keywords: Dynamic Voltage Restorer (DVR), Voltage sags, Voltage swells, Custom power, Power Quality

M. Arun Bhaskar; S. S. Dash; C. Subramani; M. Jagadeesh Kumar; P. R. Giresh; M. Varun Kumar

2010-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "voltage abnormal frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Substation voltage upgrading  

SciTech Connect

Substation voltage uprating, i.e., conversion of a substation from a lower rated voltage to a higher rated voltage without a complete substation rebuild, can lead to excellent economic benefits. Utilization of the old substation layout and/or the existing equipment, to some extent, is the practical objective of such an uprating. The objective of this project was to assess the opportunities for substation uprating in the industry, to establish feasibility for such uprating and to study methods for accomplishing it. The final aim of the project was to provide guidance to utilities interested in uprating. 56 refs., 41 figs., 18 tabs.

Panek, J.; Elahi, H.; Sublich, M. (General Electric Co., Schenectady, NY (USA). Systems Development and Engineering Dept.)

1989-08-01T23:59:59.000Z

42

Current-Voltage and Capacitance-Voltage characteristics of Pd ...  

Science Conference Proceedings (OSTI)

Presentation Title, Current-Voltage and Capacitance-Voltage characteristics of Pd ... Nonlocal Modeling in High Rate Deformation and Ductile Fracture of ...

43

High voltage DC power supply  

DOE Patents (OSTI)

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

Droege, T.F.

1989-12-19T23:59:59.000Z

44

Low-voltage gyrotrons  

SciTech Connect

For a long time, the gyrotrons were primarily developed for electron cyclotron heating and current drive of plasmas in controlled fusion reactors where a multi-megawatt, quasi-continuous millimeter-wave power is required. In addition to this important application, there are other applications (and their number increases with time) which do not require a very high power level, but such issues as the ability to operate at low voltages and have compact devices are very important. For example, gyrotrons are of interest for a dynamic nuclear polarization, which improves the sensitivity of the nuclear magnetic resonance spectroscopy. In this paper, some issues important for operation of gyrotrons driven by low-voltage electron beams are analyzed. An emphasis is made on the efficiency of low-voltage gyrotron operation at the fundamental and higher cyclotron harmonics. These efficiencies calculated with the account for ohmic losses were, first, determined in the framework of the generalized gyrotron theory based on the cold-cavity approximation. Then, more accurate, self-consistent calculations for the fundamental and second harmonic low-voltage sub-THz gyrotron designs were carried out. Results of these calculations are presented and discussed. It is shown that operation of the fundamental and second harmonic gyrotrons with noticeable efficiencies is possible even at voltages as low as 5-10 kV. Even the third harmonic gyrotrons can operate at voltages about 15 kV, albeit with rather low efficiency (1%-2% in the submillimeter wavelength region).

Glyavin, M. Yu.; Zavolskiy, N. A.; Sedov, A. S. [Institute of Applied Physics RAS, N. Novgorod 603600 (Russian Federation); Nusinovich, G. S. [IREAP, University of Maryland, College Park, Maryland 20742-3511 (United States)

2013-03-15T23:59:59.000Z

45

Comparative High Voltage Impulse Measurement  

Science Conference Proceedings (OSTI)

... substrate and surrounded by insulating oil; the low ... the amplitudes of the voltage peaks that are ... The uncertainties in the peak output voltages for the ...

2013-04-19T23:59:59.000Z

46

Device for monitoring cell voltage  

SciTech Connect

A device for monitoring a rechargeable battery having a number of electrically connected cells includes at least one current interruption switch for interrupting current flowing through at least one associated cell and a plurality of monitoring units for detecting cell voltage. Each monitoring unit is associated with a single cell and includes a reference voltage unit for producing a defined reference threshold voltage and a voltage comparison unit for comparing the reference threshold voltage with a partial cell voltage of the associated cell. The reference voltage unit is electrically supplied from the cell voltage of the associated cell. The voltage comparison unit is coupled to the at least one current interruption switch for interrupting the current of at least the current flowing through the associated cell, with a defined minimum difference between the reference threshold voltage and the partial cell voltage.

Doepke, Matthias (Garbsen, DE); Eisermann, Henning (Edermissen, DE)

2012-08-21T23:59:59.000Z

47

Electron launching voltage monitor  

DOE Patents (OSTI)

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.

Mendel, Clifford W. (Albuquerque, NM); Savage, Mark E. (Albuquerque, NM)

1992-01-01T23:59:59.000Z

48

Voltage controlled current source  

DOE Patents (OSTI)

A seven decade, voltage controlled current source is described for use in testing intermediate range nuclear instruments that covers the entire test current range of from 10 picoamperes to 100 microamperes. High accuracy is obtained throughout the entire seven decades of output current with circuitry that includes a coordinated switching scheme responsive to the input signal from a hybrid computer to control the input voltage to an antilog amplifier, and to selectively connect a resistance to the antilog amplifier output to provide a continuous output current source as a function of a preset range of input voltage. An operator controlled switch provides current adjustment for operation in either a real-time simulation test mode or a time response test mode.

Casne, Gregory M. (Pittsburgh, PA)

1992-01-01T23:59:59.000Z

49

A high-voltage low-power DC-DC buck regulator for automotive applications  

Science Conference Proceedings (OSTI)

This work presents a High-Voltage Low-Power CMOS DC-DC buck regulator for automotive applications. The overall system, including the high and low voltage analog devices, the power MOS and the low voltage digital devices, was realized in the Austriamicrosystems ... Keywords: DC-DC regulator, buck converter, current control, low quiscent current, pulse frequency modulation

G. Pasetti; L. Fanucci; R. Serventi

2010-03-01T23:59:59.000Z

50

High voltage pulse conditioning  

DOE Patents (OSTI)

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.

Stringfield, R.M.; Wheat, R.M. Jr.

1989-02-21T23:59:59.000Z

51

High voltage pulse conditioning  

DOE Patents (OSTI)

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.

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

1990-01-01T23:59:59.000Z

52

HIGH VOLTAGE GENERATOR  

DOE Patents (OSTI)

A generator is presented for producing relatively large currents at high voltages. In general, the invention comprises a plurality of capacitors connected in series by a plurality of switches alternately disposed with the capacitors. The circuit is mounted for movement with respect to contact members and switch closure means so that a load device and power supply are connected across successive numbers of capacitors, while the other capacitors are successively charged with the same power supply.

Schwemin, A.J.

1959-03-17T23:59:59.000Z

53

HIGH VOLTAGE GENERATOR  

DOE Patents (OSTI)

A generator for producing relatively large currents at high voltages is described. In general, the invention comprises a plurality of capacitors connected in series by a plurality of switches alternately disposed with the capacitors. The above-noted circuit is mounted for movement with respect to contact members and switch closure means so that a load device and power supply are connected across successive numbers of capacitors, while the other capacitors are successively charged with the same power supply.

Schwemin, A.J.

1959-03-17T23:59:59.000Z

54

Technology Assessment and Application Guide for the Utility Systems Technologies Voltage Sag Fighter  

Science Conference Proceedings (OSTI)

Voltage sag, a disturbance in a power system defined as a decrease in root mean square (RMS) voltage magnitude lasting from 0.5 to 30 cycles, has been identified as the most prevalent power disturbance experienced by industrial customers. The higher frequency of voltage sages makes them inherently more costly than interruptions since fault-induced, short-duration voltage variations can result in costly loss of production, damaged materials, repair and cleaning of equipment, and lost business opportunitie...

2010-11-29T23:59:59.000Z

55

HIGH VOLTAGE ION SOURCE  

DOE Patents (OSTI)

A device is described for providing a source of molecular ions having a large output current and with an accelerated energy of the order of 600 kv. Ions are produced in an ion source which is provided with a water-cooled source grid of metal to effect maximum recombination of atomic ions to molecular ions. A very high accelerating voltage is applied to withdraw and accelerate the molecular ions from the source, and means are provided for dumping the excess electrons at the lowest possible potentials. An accelerating grid is placed adjacent to the source grid and a slotted, grounded accelerating electrode is placed adjacent to the accelerating grid. A potential of about 35 kv is maintained between the source grid and accelerating grid, and a potential of about 600 kv is maintained between the accelerating grid and accelerating electrode. In order to keep at a minimum the large number of oscillating electrons which are created when such high voltages are employed in the vicinity of a strong magnetic field, a plurality of high voltage cascaded shields are employed with a conventional electron dumping system being employed between each shield so as to dump the electrons at the lowest possible potential rather than at 600 kv.

Luce, J.S.

1960-04-19T23:59:59.000Z

56

Energy-efficient datapath scheduling using multiple voltages and dynamic clocking  

Science Conference Proceedings (OSTI)

Recently, dynamic frequency scaling has been explored at the CPU and system levels for power optimization. Low-power datapath scheduling using multiple supply voltages has been well researched. In this work, we develop new datapath scheduling algorithms ... Keywords: High-level synthesis, dynamic frequency clocking, low-power datapath synthesis, multiple voltage scheduling, resource-constrained scheduling, time-constrained scheduling

Saraju P. Mohanty; N. Ranganathan

2005-04-01T23:59:59.000Z

57

High voltage variable diameter insulator  

DOE Patents (OSTI)

A high voltage feedthrough assembly (10) having a tubular insulator (15) extending between the ground plane ring (16) and the high voltage ring (30). The insulator (15) is made of Pyrex and decreases in diameter from the ground plane ring (16) to the high voltage ring (30), producing equipotential lines almost perpendicular to the wall (27) of the insulator (15) to optimize the voltage-holding capability of the feedthrough assembly (10).

Vanecek, David L. (Martinez, CA); Pike, Chester D. (Pinole, CA)

1984-01-01T23:59:59.000Z

58

Automatic voltage-imbalance detector  

DOE Patents (OSTI)

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

Bobbett, R.E.; McCormick, J.B.; Kerwin, W.J.

1981-05-20T23:59:59.000Z

59

E-beam high voltage switching power supply  

DOE Patents (OSTI)

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

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

1996-01-01T23:59:59.000Z

60

E-beam high voltage switching power supply  

DOE Patents (OSTI)

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

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

1996-10-15T23:59:59.000Z

Note: This page contains sample records for the topic "voltage abnormal frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Low-voltage-swing Monolithic DC-DC Conversion  

E-Print Network (OSTI)

Abstract—A low-voltage-swing MOSFET gate drive technique is proposed in this paper for enhancing the efficiency characteristics of high-frequency-switching dc–dc converters. The parasitic power dissipation of a dc–dc converter is reduced by lowering the voltage swing of the power transistor gate drivers. A comprehensive circuit model of the parasitic impedances of a monolithic buck converter is presented. Closed-form expressions for the total power dissipation of a low-swing buck converter are proposed. The effect of reducing the MOSFET gate voltage swings is explored with the proposed circuit model. A range of design parameters is evaluated, permitting the development of a design space for full integration of active and passive devices of a low-swing buck converter on the same die, for a target CMOS technology. The optimum gate voltage swing of a power MOSFET that maximizes efficiency is lower than a standard full voltage swing. An efficiency of 88 % at a switching frequency of 102 MHz is achieved for a voltage conversion from 1.8 to 0.9 V with a low-swing dc–dc converter based on a 0.18- m CMOS technology. The power dissipation of a low-swing dc–dc converter is reduced by 27.9 % as compared to a standard full-swing dc–dc converter. Index Terms—Buck converter, dc–dc converters, enhanced efficiency, high frequency, low power, low swing, monolithic integration, on-chip voltage conversion, parameter optimization, parasitic impedances, power dissipation modeling, power supply, reduced energy dissipation, reduced voltage swing, switching voltage regulator. I.

Volkan Kursun; Siva G. Narendra; Vivek K. De; Eby G. Friedman

2004-01-01T23:59:59.000Z

62

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

DOE Patents (OSTI)

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.

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

1995-01-01T23:59:59.000Z

63

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

DOE Patents (OSTI)

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

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

1995-05-23T23:59:59.000Z

64

FAST: Frequency-aware static timing analysis  

Science Conference Proceedings (OSTI)

Energy is a valuable resource in embedded systems as the lifetime of many such systems is constrained by their battery capacity. Recent advances in processor design have added support for dynamic frequency/voltage scaling (DVS) for saving energy. Recent ... Keywords: Real-time systems, dynamic voltage scaling, scheduling, worst-case execution time analysis

Kiran Seth; Aravindh Anantaraman; Frank Mueller; Eric Rotenberg

2006-02-01T23:59:59.000Z

65

Planning of distribution networks for medium voltage and low voltage.  

E-Print Network (OSTI)

??Determination of the placement and rating of transformers and feeders are the main objective of the basic distribution network planning. The bus voltage and the… (more)

Ziari, Iman

2011-01-01T23:59:59.000Z

66

High voltage feedthrough bushing  

DOE Patents (OSTI)

A feedthrough bushing for a high voltage diode provides for using compression sealing for all sealing surfaces. A diode assembly includes a central conductor extending through the bushing and a grading ring assembly circumferentially surrounding and coaxial with the central conductor. A flexible conductive plate extends between and compressively seals against the central conductor and the grading ring assembly, wherein the flexibility of the plate allows inner and outer portions of the plate to axially translate for compression sealing against the central conductor and the grading ring assembly, respectively. The inner portion of the plate is bolted to the central conductor for affecting sealing. A compression beam is also bolted to the central conductor and engages the outer portion of the plate to urge the outer portion toward the grading ring assembly to obtain compression sealing therebetween.

Brucker, J.P.

1991-12-31T23:59:59.000Z

67

Very-High-Frequency Resonant Boost Converters  

E-Print Network (OSTI)

This paper presents a resonant boost topology suitable for very-high-frequency (VHF, 30-300 MHz) DC-DC power conversion. The proposed design features low device voltage stress, high efficiency over a wide load range, and ...

Perreault, David J.

68

Voltage Vehicles | Open Energy Information  

Open Energy Info (EERE)

Sector Vehicles Product Voltage Vehicles is a nascent, full-service alternative fuel vehicle distributor specializing in the full spectrum of electric vehicles (EV) and...

69

Humidity, Temperature, and Voltage (Presentation)  

SciTech Connect

An update is given on the work of the PV Quality Assurance Task Force; Group 3: studying the effects of humidity, temperature, and voltage bias.

Wohlgemuth, J.

2012-03-01T23:59:59.000Z

70

Easily disassembled electrical connector for high voltage, high frequency connections  

DOE Patents (OSTI)

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

Milner, J.R.

1994-05-10T23:59:59.000Z

71

Strain-optic voltage monitor  

DOE Patents (OSTI)

A voltage monitor which uses the shift in absorption edge of crystalline material to measure strain resulting from electric field-induced deformation of piezoelectric or electrostrictive material, providing a simple and accurate means for measuring voltage applied either by direct contact with the crystalline material or by subjecting the material to an electric field.

Weiss, J.D.

1995-12-31T23:59:59.000Z

72

Dynamic Voltage Scaling on a Low-Power Microprocessor  

E-Print Network (OSTI)

Power consumption is the limiting factor for the functionality of future wearable devices. Since interactive applications like wireless information access generate bursts of activities, it is important to match the performance of the wearable device accordingly. This paper describes a system with a microprocessor whose speed can be varied (frequency scaling) as well as its input voltage. Voltage scaling is important for reducing power consumption to very low values when operating at low speeds. Measurements show that the energy per instruction at minimal speed (59 MHz) is 1/5 of the energy required at full speed (251 MHz). The frequency and voltage can be scaled dynamically from user space in only 140 ¡ s. This allows power-aware applications to quickly adjust the performance level of the processor whenever the workload changes. 1

Johan Pouwelse; Koen Langendoen; Henk Sips

2001-01-01T23:59:59.000Z

73

Two terminal line voltage thermostat  

Science Conference Proceedings (OSTI)

A two terminal line voltage thermostat includes a switch which effectively connects line voltage to a heater load. The entire process is controlled by an integrated circuit microcontroller which is powered by a rectified voltage from a transformer secondary connected to a primary which is in series with the heater load. Backup battery power is provided to maintain limited functions of the microcontroller in the event of overall power loss. The microcontroller is programmed to meet the temperature sensing and control requirements specific to a two terminal electric baseboard heating installation. 7 figs.

Stalsberg, K.J.; Ingalls, J.E.; Hoglund, S.R.

1995-10-10T23:59:59.000Z

74

Current status of CMOS low voltage and low power wireless IC designs  

Science Conference Proceedings (OSTI)

This paper surveys recent research on CMOS low voltage and low power IC designs for wireless applications. Advancements and challenges in using nanometer IC processes are addressed, and the impacts of device scaling on wireless systems are discussed. ... Keywords: CMOS, Integrated Circuits (IC), Low-Power, Low-Voltage, Nanometer, Radio Frequency (RF), Sub-1V, Wireless

Tommy K. Tsang; Mourad N. El-Gamal; Krzysztof Iniewski; Kenneth A. Townsend; James W. Haslett; Yanjie Wang

2007-10-01T23:59:59.000Z

75

FPGA Implementation of Space Vector PWM Technique for Voltage Source Inverter Fed Induction Motor Drive  

Science Conference Proceedings (OSTI)

This paper presents implementation of Space Vector Pulse Width Modulation (SVPWM) technique for three phase Voltage Source Inverter (VSI) using Field Programmable Gate Array (FPGA). Variable voltage and frequency supply to ac drives is invariably obtained ... Keywords: VSI, SVPWM, FPGA, Induction Motor

R. Rajendran; N. Devarajan

2009-12-01T23:59:59.000Z

76

Chapter 4 - Understanding Voltage Sags  

Science Conference Proceedings (OSTI)

This chapter of the EPRI Solutions PQ Encyclopedia provides information for understanding the voltage sag, which is the single most potent cause of end user power quality (PQ) problems.

2005-12-31T23:59:59.000Z

77

Definition: Automated Voltage Regulators | Open Energy Information  

Open Energy Info (EERE)

Regulators Regulators Jump to: navigation, search Dictionary.png Automated Voltage Regulators Voltage regulators are transformers that can increase or decrease the voltage on a distribution circuit to help keep the voltage within a pre-determined band. Unlike capacitor banks, voltage regulators cannot adjust power factor. These devices typically monitor the voltage at the location where they are connected, and compare it to a programmed set point. If the voltage deviates too far from the set point, the voltage regulator can increase or decrease its output voltage by moving the tap on the secondary side up or down. An automated voltage regulator can operate with remote control signals, or in concert with other area voltage control devices, to help regulate distribution voltage in a coordinated fashion.

78

High-voltage-compatible, fully depleted CCDs  

E-Print Network (OSTI)

result of this high-voltage requirement, we have taken a di?voltage is necessary in order to meet the PSF requirementsrequirements for SNAP have resulted in a need to operate at substrate bias voltages

2006-01-01T23:59:59.000Z

79

E-beam high voltage switching power supply  

DOE Patents (OSTI)

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

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

1997-01-01T23:59:59.000Z

80

E-beam high voltage switching power supply  

DOE Patents (OSTI)

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

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

1997-03-11T23:59:59.000Z

Note: This page contains sample records for the topic "voltage abnormal frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

High voltage electrical amplifier having a short rise time  

DOE Patents (OSTI)

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 the voltage of the output. The preferred embodiment also comprises a low voltage power supply for biasing the FETs at or near an operational voltage. 8 figs.

Christie, D.J.; Dallum, G.E.

1989-12-07T23:59:59.000Z

82

High voltage electrical amplifier having a short rise time  

DOE Patents (OSTI)

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

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

1991-01-01T23:59:59.000Z

83

Performance of Dynamic Voltage Restorer (DVR) against Voltage Sags and Swells Using Space Vector PWM Technique  

Science Conference Proceedings (OSTI)

Due to increasing complexity in the power system, voltage sags are now becoming one of the most significant power quality problems. Voltage sag is a short reduction voltage from nominal voltage, occurs in a short time. Short-lived voltage sags may not ... Keywords: Custom power, power quality, voltage sag, SPWM, SVPWM, DVR, PSCAD/EMTDC.

Palaparthi Ananthababu; Burle Trinadha; K. Ram Charan

2009-12-01T23:59:59.000Z

84

A CMOS threshold voltage reference source for very-low-voltage applications  

Science Conference Proceedings (OSTI)

This paper describes a CMOS voltage reference that makes use of weak inversion CMOS transistors and linear resistors, without the need for bipolar transistors. Its operation is analogous to the bandgap reference voltage, but the reference voltage is ... Keywords: Threshold voltage, Ultra-low-power, Very-low-voltage, Voltage reference

Luis H. C. Ferreira; Tales C. Pimenta; Robson L. Moreno

2008-12-01T23:59:59.000Z

85

Surge voltage suppression in residential power circuits  

Science Conference Proceedings (OSTI)

... Tran- sients in Low Voltage Supply Systems,'' The ... a high-voltage transformer for an oil furnace ... of service entrance SPD of 1960-1970 vintage were ...

2013-05-17T23:59:59.000Z

86

High frequency reference electrode  

DOE Patents (OSTI)

A high frequency reference electrode for electrochemical experiments comprises a mercury-calomel or silver-silver chloride reference electrode with a layer of platinum around it and a layer of a chemically and electrically resistant material such as TEFLON around the platinum covering all but a small ring or halo'' at the tip of the reference electrode, adjacent to the active portion of the reference electrode. The voltage output of the platinum layer, which serves as a redox electrode, and that of the reference electrode are coupled by a capacitor or a set of capacitors and the coupled output transmitted to a standard laboratory potentiostat. The platinum may be applied by thermal decomposition to the surface of the reference electrode. The electrode provides superior high-frequency response over conventional electrodes.

Kronberg, J.W.

1991-03-05T23:59:59.000Z

87

High frequency reference electrode  

DOE Patents (OSTI)

A high frequency reference electrode for electrochemical experiments comprises a mercury-calomel or silver-silver chloride reference electrode with a layer of platinum around it and a layer of a chemically and electrically resistant material such as TEFLON around the platinum covering all but a small ring or halo' at the tip of the reference electrode, adjacent to the active portion of the reference electrode. The voltage output of the platinum layer, which serves as a redox electrode, and that of the reference electrode are coupled by a capacitor or a set of capacitors and the coupled output transmitted to a standard laboratory potentiostat. The platinum may be applied by thermal decomposition to the surface of the reference electrode. The electrode provides superior high-frequency response over conventional electrodes. 4 figs.

Kronberg, J.W.

1994-05-31T23:59:59.000Z

88

High frequency reference electrode  

DOE Patents (OSTI)

A high frequency reference electrode for electrochemical experiments comprises a mercury-calomel or silver-silver chloride reference electrode with a layer of platinum around it and a layer of a chemically and electrically resistant material such as TEFLON around the platinum covering all but a small ring or "halo" at the tip of the reference electrode, adjacent to the active portion of the reference electrode. The voltage output of the platinum layer, which serves as a redox electrode, and that of the reference electrode are coupled by a capacitor or a set of capacitors and the coupled output transmitted to a standard laboratory potentiostat. The platinum may be applied by thermal decomposition to the surface of the reference electrode. The electrode provides superior high-frequency response over conventional electrodes.

Kronberg, James W. (Aiken, SC)

1994-01-01T23:59:59.000Z

89

Automated Voltage Control in LHCb  

E-Print Network (OSTI)

LHCb is one of the 4 LHC experiments. In order to ensure the safety of the detector and to maximize efficiency, LHCb needs to coordinate its own operations, in particular the voltage configuration of the different subdetectors, according to the accelerator status. A control software has been developed for this purpose, based on the Finite State Machine toolkit and the SCADA system used for control throughout LHCb (and the other LHC experiments). This software permits to efficiently drive both the Low Voltage (LV) and High Voltage (HV) systems of the 10 different sub-detectors that constitute LHCb, setting each sub-system to the required voltage (easily configurable at run-time) based on the accelerator state. The control software is also responsible for monitoring the state of the Sub-detector voltages and adding it to the event data in the form of status-bits. Safe and yet flexible operation of the LHCb detector has been obtained and automatic actions, triggered by the state changes of the ...

Granado Cardoso, L; Jacobsson, R

2011-01-01T23:59:59.000Z

90

Fiber-optic voltage sensor  

DOE Patents (OSTI)

A fiber optic voltage sensor is described which includes a source of light, a reference fiber for receiving a known percentage of the light and an electrostrictive element having terminals across which is applied, a voltage to be measured. The electrostrictive element is responsive to the applied voltage to assume an altered physical state. A measuring fiber also receives a known percentage of light from the light source and is secured about the electrostrictive element. The measuring fiber is provided with a cladding and exhibits an evanescent wave in the cladding. The measuring fiber has a known length which is altered when the electrostrictive element assumes its altered physical state. A differential sensor is provided which senses the intensity of light in both the reference fiber and the measuring fiber and provides an output indicative of the difference between the intensities.

Wood, C.B.

1990-12-31T23:59:59.000Z

91

A voltage controlled current source  

DOE Patents (OSTI)

A seven decade, voltage controlled current source is described for use in testing intermediate range nuclear instruments that covers the entire test current range of from 10 picoampers to 100 microamperes. High accuracy is obtained throughout the entire seven decades of output current with circuitry that includes a coordinated switching scheme responsive to the input signal from a hybrid computer to control the input voltage to an antilog amplifier, and to selectively connect a resistance to the antilog amplifier output to provide a continuous output current source as a function of a preset range of input voltage. An operator controlled switch provides current adjustment for operation in either a real-time simulation test mode or a time response test mode.

Casne, G.M.

1990-12-21T23:59:59.000Z

92

Fiber-optic voltage sensor  

DOE Patents (OSTI)

A fiber optic voltage sensor is described which includes a source of light, a reference fiber for receiving a known percentage of the light and an electrostrictive element having terminals across which is applied, a voltage to be measured. The electrostrictive element is responsive to the applied voltage to assume an altered physical state. A measuring fiber also receives a known percentage of light from the light source and is secured about the electrostrictive element. The measuring fiber is provided with a cladding and exhibits an evanescent wave in the cladding. The measuring fiber has a known length which is altered when the electrostrictive element assumes its altered physical state. A differential sensor is provided which senses the intensity of light in both the reference fiber and the measuring fiber and provides an output indicative of the difference between the intensities.

Wood, C.B.

1990-01-01T23:59:59.000Z

93

Portec Voltage Regulators: for Emergency Diesel Generators  

Science Conference Proceedings (OSTI)

This report contains information to help utilities address emergency diesel generator voltage regulator issues.

2004-12-15T23:59:59.000Z

94

Ancillary service details: Voltage control  

SciTech Connect

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.

Kirby, B.; Hirst, E.

1997-12-01T23:59:59.000Z

95

Probabilistic voltage assessment and VAR compensation  

SciTech Connect

The system voltage profile subject to system elements' forced outage is accessed. Two system voltage reliability indexes are evaluated: the loss of voltage probability, and the expected voltage violation. A similar set of two voltage reliability indexes are also calculated for every load bus in the system. A simple VAR compensation approach is introduced. It enhances the voltage profile assuming a maximum of three overlapping element outages can occur. For purposes of demonstration, the system and load bus voltage reliability indexes are calculated for the AEP 30-bus system. Results of applying the proposed VAR compensation scheme to the 30-bus system are also presented and discussed.

Sharaf, T.A.M.; Berg, G.J.

1988-01-01T23:59:59.000Z

96

Pulsed voltage electrospray ion source and method for preventing analyte electrolysis  

SciTech Connect

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.

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

2011-12-27T23:59:59.000Z

97

Stability issues in IC Low Drop Out voltage regulators  

E-Print Network (OSTI)

Performance issues of IC Low Drop Out (LDO) voltage regulators, with specific reference to stability, are discussed in this thesis. Evaluation of existing frequency compensation schemes and their performances across operating loads is presented. The problem of instability of the LDO voltage regulator at low Electo Static Resistance (ESR) of the load capacitors and the consequences of this problem are highlighted. As a solution to some of the discussed problems, an alternate LDO voltage regulator topology that is stable with low Electro Static Resistance (ESR) capacitive loads is presented. The proposed scheme, instead of relying on the zero generated by the load capacitor and its ESR combination for stability, generates a zero internally. The LDO voltage regulator is implemented and fabricated in AMI 0.5mm CMOS technology through MOSIS service. It is demonstrated that this scheme realizes robust frequency compensation, facilitates use of Multi Layer Ceramic Capacitors (MLCC) for load of LDO regulators, and improves transient response and noise performance. Test results from the prototype provide an evaluation of the most important parameters of the regulator: ground current, load regulation, line regulation, output noise and start-up time.

Chava, Krishna Chaitanya

2002-01-01T23:59:59.000Z

98

Study of abnormal combustion oscillations in gas fired appliances.  

E-Print Network (OSTI)

??The thesis work discusses abnormal combustion noise in gas-fired appliances. An experimental model was made to provide insight into the causes of abnormal combustion noises.… (more)

Kumar, Dasari

2006-01-01T23:59:59.000Z

99

An efficient CMOS rectifier with low-voltage operation for RFID tags  

Science Conference Proceedings (OSTI)

A high-efficiency CMOS rectifier for radio-frequency identification (RFID) applications is presented. Using an on-chip generated clock signal, a new switching scheme is proposed to enhance the power efficiency of the conventional 4 transistor (4T)-cell ... Keywords: frequency 950 MHz, efficient CMOS rectifier, low-voltage operation, RFID tags, radio-frequency identification applications, on-chip generated clock signal, power efficiency, conventional 4 transistor-cell rectifier, charge-transfer transistors, small leakage current, external gate-boosting technique, nominal standard threshold voltage, MOS transistors, CMOS technology, power conversion efficiency

P. Kamalinejad; S. Mirabbasi; V. C. M. Leung

2011-07-01T23:59:59.000Z

100

High voltage photovoltaic power converter  

DOE Patents (OSTI)

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

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

2001-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "voltage abnormal frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

TRANSISTOR HIGH VOLTAGE POWER SUPPLY  

DOE Patents (OSTI)

High voltage, direct current power supplies are described for use with battery powered nuclear detection equipment. The particular advantages of the power supply described, are increased efficiency and reduced size and welght brought about by the use of transistors in the circuit. An important feature resides tn the employment of a pair of transistors in an alternatefiring oscillator circuit having a coupling transformer and other circuit components which are used for interconnecting the various electrodes of the transistors.

Driver, G.E.

1958-07-15T23:59:59.000Z

102

Radio frequency coaxial feedthrough  

DOE Patents (OSTI)

An improved radio frequency coaxial transmission line vacuum feed-through provided based on the use of a half-wavelength annular dielectric pressure barrier disk, or multiple disks comprising an effective half wavelength structure to eliminate reflections from the barrier surfaces. Gas-tight seals are formed about the outer and inner diameter surfaces of the barrier disk using a sealing technique which generates radial forces sufficient to form seals by forcing the conductor walls against the surfaces of the barrier disks in a manner which does not deform the radii of the inner and outer conductors, thereby preventing enhancement of the electric field at the barrier faces which limits voltage and power handling capabilities of a feedthrough.

Owens, Thomas L. (Kingston, TN)

1989-01-17T23:59:59.000Z

103

Detector for flow abnormalities in gaseous diffusion plant compressors  

DOE Patents (OSTI)

A detector detects a flow abnormality in a plant compressor which outputs a motor current signal. The detector includes a demodulator/lowpass filter demodulating and filtering the motor current signal producing a demodulated signal, and first, second, third and fourth bandpass filters connected to the demodulator/lowpass filter, and filtering the demodulated signal in accordance with first, second, third and fourth bandpass frequencies generating first, second, third and fourth filtered signals having first, second, third and fourth amplitudes. The detector also includes first, second, third and fourth amplitude detectors connected to the first, second, third and fourth bandpass filters respectively, and detecting the first, second, third and fourth amplitudes, and first and second adders connected to the first and fourth amplitude detectors and the second and third amplitude detectors respectively, and adding the first and fourth amplitudes and the second and third amplitudes respectively generating first and second added signals. Finally, the detector includes a comparator, connected to the first and second adders, and comparing the first and second added signals and detecting the abnormal condition in the plant compressor when the second added signal exceeds the first added signal by a predetermined value.

Smith, Stephen F. (Loudon, TN); Castleberry, Kim N. (Harriman, TN)

1998-01-01T23:59:59.000Z

104

Detector for flow abnormalities in gaseous diffusion plant compressors  

DOE Patents (OSTI)

A detector detects a flow abnormality in a plant compressor which outputs a motor current signal. The detector includes a demodulator/lowpass filter demodulating and filtering the motor current signal producing a demodulated signal, and first, second, third and fourth bandpass filters connected to the demodulator/lowpass filter, and filtering the demodulated signal in accordance with first, second, third and fourth bandpass frequencies generating first, second, third and fourth filtered signals having first, second, third and fourth amplitudes. The detector also includes first, second, third and fourth amplitude detectors connected to the first, second, third and fourth bandpass filters respectively, and detecting the first, second, third and fourth amplitudes, and first and second adders connected to the first and fourth amplitude detectors and the second and third amplitude detectors respectively, and adding the first and fourth amplitudes and the second and third amplitudes respectively generating first and second added signals. Finally, the detector includes a comparator, connected to the first and second adders, and comparing the first and second added signals and detecting the abnormal condition in the plant compressor when the second added signal exceeds the first added signal by a predetermined value. 6 figs.

Smith, S.F.; Castleberry, K.N.

1998-06-16T23:59:59.000Z

105

Voltage unbalance effects on induction motor performance  

Science Conference Proceedings (OSTI)

The reliability of electric drives and driven motors depends on the quality of the power supply voltage especially in the critical industrial process. In this work, a theoretical study of the effects of voltage unbalances, sags and swells on induction ... Keywords: efficiency, power losses and derating factor, sags, symmetrical components, voltage unbalance

L. Refoufi; H. Bentarzi; F. Z. Dekhandji

2006-09-01T23:59:59.000Z

106

Synchronizing carrier frequencies of co-channel amplitude-modulated broadcast  

DOE Patents (OSTI)

Systems and methods are described for carrier-frequency synchronization for improved AM and TV broadcast reception. A method includes synchronizing a carrier frequency of a broadcast signal with a remote reference frequency. An apparatus includes a reference signal receiver; a phase comparator coupled to the reference signal receiver; a voltage controlled oscillator coupled to the phase comparator; and a radio frequency output coupled to the voltage controlled oscillator.

Smith, Stephen F. (London, TN); Moore, James A. (Powell, TN)

2007-05-15T23:59:59.000Z

107

Gene Frequency  

NLE Websites -- All DOE Office Websites (Extended Search)

Gene Frequency Gene Frequency Name: donna Location: N/A Country: N/A Date: N/A Question: If six fingers is a dominant human trait why do we have only five? Replies: This is simple. There are just not many genes in the human population for six fingers. Steve Sample Look in any high school biology book for what is known as Hardy-Weinberg equilibrium. These two scientists (separately) said that gene frequencies do not change much unless something in the environment selects them over other genes. In other words, unless 6 fingers somehow becomes an advantage, and five-fingered people have less of an advantage, the frequency of six fingered people in the population will not necessarily increase. This is the same reason that recessive traits don't disappear from the population. Also, six fingers is not considered attractive and they may not get as many mates. Also, more people are born with six fingers than you might imagine but just have them amputated shortly after birth.

108

Influence of voltage drop to electric drive with induction motor and voltage sourced inverter  

Science Conference Proceedings (OSTI)

This paper solves problematic of immunity from the voltage drop of the power supply of the electric drive with induction motor with Voltage-Fed inverter. There are reflected opportune control algorithms for the quickly to change of working regime from ... Keywords: electric drive with induction motor, electric drive with voltage sourced inverter, voltage drop

P. Beneš; J. Fo?t; M. Pittermann

2011-09-01T23:59:59.000Z

109

Operational Results of Pulse Shaping Techniques for the High Voltage Convertor Modulator  

Science Conference Proceedings (OSTI)

The High Voltage Converter Modulators (HVCMs) are used to power the RF klystrons used throughout the accelerator systems at Spallation Neutron Source (SNS). The output voltage of the HVCM has significant droop and ripple which, combined with low level RF (LLRF) system limitations, affect performance and efficiency of accelerator cavities. In conjunction with the progress in development of the new HVCM controller, different pulse modulation techniques were implemented and studied on the test modulator. This paper discusses the results of implementation of frequency modulation and phase modulation on output voltage. Operational data, including full average power operation, of test modulator is also discussed. Future plans for the new modulation scheme will be presented.

Patel, Gunjan P [ORNL; Anderson, David E [ORNL; Solley, Dennis J [ORNL; Wezensky, Mark W [ORNL

2012-01-01T23:59:59.000Z

110

Low power, scalable multichannel high voltage controller  

DOE Patents (OSTI)

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

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

2006-03-14T23:59:59.000Z

111

Low power, scalable multichannel high voltage controller  

DOE Patents (OSTI)

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

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

2008-03-25T23:59:59.000Z

112

Dynamic Voltage Regulation Using Distributed Energy Resources  

Science Conference Proceedings (OSTI)

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.

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

2007-01-01T23:59:59.000Z

113

Characterisation of the VELO High Voltage System  

E-Print Network (OSTI)

The high voltage system supplies the bias voltage to the 88 silicon sensors which comprise the LHCb Vertex Locator (VELO). This note describes the results of the tests which have been performed on the hardware of the high voltage system of the VELO. Each individual test detailed in this note corresponds to a specific requirement of the system. These requirements arise primarily from ensuring the safety of the silicon sensors and the quality of the data taken from the VELO modules. The tests performed are in four categories: normal operation of the high voltage system; verification of its stability under operation; discussion of its behaviour in failure modes; and details of operation at low voltage. Noteworthy issues, identified through the tests, include the behaviour of the high voltage modules at voltages below 9V, the current limit that can be applied during ramping of the voltage, and the speed with which the voltage is cut during failures of the system. The results of these tests provide high confidence that the high voltage system can be safely used and demonstrate that low noise is produced by the power supplies. LHCb Public Note, LHCb-2008-009Contents 1

Barinjaka Rakotomiaramanana; Chris Parkes; Lars Eklund

2008-01-01T23:59:59.000Z

114

Variable frequency microwave furnace system  

DOE Patents (OSTI)

A variable frequency microwave furnace system designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity for testing or other selected applications. The variable frequency microwave furnace system includes a microwave signal generator or microwave voltage-controlled oscillator for generating a low-power microwave signal for input to the microwave furnace. A first amplifier may be provided to amplify the magnitude of the signal output from the microwave signal generator or the microwave voltage-controlled oscillator. A second amplifier is provided for processing the signal output by the first amplifier. The second amplifier outputs the microwave signal input to the furnace cavity. In the preferred embodiment, the second amplifier is a traveling-wave tube (TWT). A power supply is provided for operation of the second amplifier. A directional coupler is provided for detecting the direction of a signal and further directing the signal depending on the detected direction. A first power meter is provided for measuring the power delivered to the microwave furnace. A second power meter detects the magnitude of reflected power. Reflected power is dissipated in the reflected power load. 5 figs.

Bible, D.W.; Lauf, R.J.

1994-06-14T23:59:59.000Z

115

Definition: Operating Voltage | Open Energy Information  

Open Energy Info (EERE)

Voltage Voltage Jump to: navigation, search Dictionary.png Operating Voltage The voltage level by which an electrical system is designated and to which certain operating characteristics of the system are related; also, the effective (root-mean-square) potential difference between any two conductors or between a conductor and the ground. The actual voltage of the circuit may vary somewhat above or below this value.[1] Related Terms system References ↑ Glossary of Terms Used in Reliability Standards An LikeLike UnlikeLike You like this.Sign Up to see what your friends like. inline Glossary Definition Retrieved from "http://en.openei.org/w/index.php?title=Definition:Operating_Voltage&oldid=480559" Categories: Definitions ISGAN Definitions What links here Related changes

116

The effect of DVR location for enhancing voltage sag  

Science Conference Proceedings (OSTI)

Recently, Dynamic Voltage Restorer (DVR) has become a popular power electronic device as a protection for sensitive loads from voltage sag. Voltage sag widely known as one of the major problem in power quality, it is defined as a short reduction of voltage ... Keywords: dynamic voltage restorer, power quality, voltage sag

Rohanim Ibrahim; Ahmed M. A. Haidar; M. Zahim; Herbert Iu

2010-03-01T23:59:59.000Z

117

Lowering Power using the Voltage Identification Bit  

E-Print Network (OSTI)

Voltage identification is a form of adaptive voltage scaling (AVS). The voltage-identification technique described in this application note enables certain devices in the Virtex®-7 family to be operated at a lower voltage of 0.9V while delivering the same specified performance as that of a device operating at the nominal supply voltage of 1.0V. Voltage identification capable devices consume approximately 30 % lower worst case (maximum) static power and correspondingly dissipate less heat. Reduced power consumption is a desirable characteristic and one that Xilinx 7 series FPGAs fulfill in multiple ways. The primary purpose of the voltage-identification technique is to reduce the worst-case power consumption of-1C devices. However, the significance of the voltage-identification technique goes beyond an individual device dissipating less energy, it also can lower the overall system cost. Power supplies and thermal management requirements are normally specified based on the worst-case power demands of all the system’s components. Although the 7 series FPGAs-1C devices are the most cost-effective, the total cost of a product is the sum of all parts, and costs associated with the power supply and thermal management can be significant. The voltage-identification technique specifically reduces worst-case power consumption, which reduces the overall costs associated with specifying a larger power supply, requiring a heat sink, adding forced air cooling, or including similar devices. This application note shows the technical aspects of implementing the voltage-identification technique and introduces a reference design for the VC707 evaluation kit. It also explains how voltage identification fits into the complete power portfolio of Virtex-7 FPGAs and highlights the benefits of using the voltage-identification technique to reduce power consumption and system costs.

Ken Chapman; Jameel Hussein

2012-01-01T23:59:59.000Z

118

Emergency Diesel Generator Voltage Regulator Guidelines  

Science Conference Proceedings (OSTI)

This product kit, containing six separate documents, provides information to help utilities address emergency diesel generator voltage regulator issues and maintenance.

2005-12-20T23:59:59.000Z

119

Characterisation of the VELO High Voltage System  

E-Print Network (OSTI)

The high voltage system supplies the bias voltage to the 88 silicon sensors which comprise the LHCb Vertex Locator (VELO). This note describes the results of the tests which have been performed on the hardware of the high voltage system of the VELO. Each individual test detailed in this note corresponds to a specific requirement of the system. These requirements arise primarily from ensuring the safety of the silicon sensors and the quality of the data taken from the VELO modules. The tests performed are in four categories: normal operation of the high voltage system; vercation of its stability under operation; discussion of its behaviour in failure modes; and details of operation at low voltage. Noteworthy issues, identified through the tests, include the behaviour of the high voltage modules at voltages below 9V, the current limit that can be applied during ramping of the voltage, and the speed with which the voltage is cut during failures of the system. The results of these tests provide high confidence th...

Rakotomiaramanana, B; Eklund, L

2008-01-01T23:59:59.000Z

120

Characterisation of the VELO High Voltage System  

E-Print Network (OSTI)

The high voltage system supplies the bias voltage to the 88 silicon sensors which comprise the LHCb Vertex Locator (VELO). This note describes the results of the tests which have been performed on the hardware of the high voltage system of the VELO. Each individual test detailed in this note corresponds to a specific requirement of the system. These requirements arise primarily from ensuring the safety of the silicon sensors and the quality of the data taken from the VELO modules. The tests performed are in four categories: normal operation of the high voltage system; verification of its stability under operation; discussion of its behaviour in failure modes; and details of operation at low voltage. Noteworthy issues, identified through the tests, include the behaviour of the high voltage modules at voltages below 9V, the current limit that can be applied during ramping of the voltage, and the speed with which the voltage is cut during failures of the system. The results of these tests provide high confidence...

Rakotomiaramanana, B; Eklund, L

2008-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "voltage abnormal frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Enhancing Open Circuit Voltage by Combining Thermoelectric ...  

Science Conference Proceedings (OSTI)

Enhancing Open Circuit Voltage by Combining Thermoelectric Materials and Dye -Sensitized Solar Cell in Series · Estimation of Compressive Strength of High ...

122

Group 3: Humidity, Temperature, and Voltage (Presentation)  

DOE Green Energy (OSTI)

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.

Wohlgemuth, J.

2013-05-01T23:59:59.000Z

123

Voltage Source Converter Technology for Offshore Grids.  

E-Print Network (OSTI)

??This master thesis has investigated the possible application of voltage source converters (VSC) for the interconnection of offshore installations, i.e. wind farms and petroleum platforms,… (more)

Vormedal, Pål Kristian Myhrer

2010-01-01T23:59:59.000Z

124

Quantum Voltage System Development and Dissemination  

Science Conference Proceedings (OSTI)

... of the unit of electric potential difference, the volt, and precise techniques for measuring voltage are essential to the electrical ... Facilities/Tools Used: ...

2012-11-14T23:59:59.000Z

125

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

SciTech Connect

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.

Pitel, Ira J. (Whippany, NJ)

1987-02-03T23:59:59.000Z

126

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

SciTech Connect

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.

Pitel, I.J.

1987-02-03T23:59:59.000Z

127

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

128

Aalborg Universitet Mitigation of Voltage Sags in CIGRE Low Voltage Distribution Network  

E-Print Network (OSTI)

software version 15.0. Index Terms--Wind Turbine Generator (WTG), Photovoltaic (PV), Voltage Source of voltage sags. I. INTRODUCTION Power quality, reliability and stability are the prime requirement of modern

Bak-Jensen, Birgitte

129

Low voltage ride-through capability improvement of wind power generation using dynamic voltage restorer  

Science Conference Proceedings (OSTI)

Recently, the total amount of generation from wind power plants has been increased all over the world. In this situation, a large amount of disconnection of wind generation may give a serious influence in the power system. Consequently, Low Voltage Ride-Through ... Keywords: dynamic voltage restorer, energy storage, fault ride-through, fixed-speed induction generator, low voltage ride-through, voltage sag, wind power generation

Naohiro Hasegawa; Teruhisa Kumano

2010-02-01T23:59:59.000Z

130

Understanding the unbalanced-voltage problem in wind turbine generation  

DOE Green Energy (OSTI)

Most wind turbines are equipped with line-connected induction generators. Induction generators are very attractive as wind turbine generators due to their low cost, ruggedness and the need for little or no maintenance. At constant frequency, the induction generator operates in a small range of speeds and, therefore, it operated with a small range of slips with respect to synchronous speed. Compared to a synchronous generator, an induction generator provides lower stiffness, thus alleviating the mechanical stress. In a weak power system network, an unbalanced load at the distribution lines can cause unbalanced voltage conditions. If an induction generator is connected to an unbalanced voltage, the resulting stator current will be unbalanced. The unbalanced current creates unequal heating (hot spots) on the stator winding. The heat may increase the winding temperature, which degrades the insulation of the winding, i.e., the life expectancy of the winding. Unbalanced currents also create torque pulsation on the shaft resulting in audible noise and extra mechanical stress. This paper explores the unbalanced voltage problem in induction generators. The levels of unbalance and the loads are varied. Experimental and predicted results are presented in this paper.

Muljadi, E.; Butterfield, C.P.; Batan, T.; Yildirim, D.

2000-02-28T23:59:59.000Z

131

Ultra-low voltage resonant tunnelling diode electroabsorption modulator  

E-Print Network (OSTI)

Embedding a double barrier resonant tunnelling diode (RTD) in an unipolar InGaAlAs optical waveguide gives rise to a very low driving voltage electroabsorption modulator (EAM) at optical wavelengths around 1550 nm. The presence of the RTD within the waveguide core introduces high non-linearity and negative differential resistance in the current-voltage (I-V) characteristic of the waveguide. This makes the electric field distribution across the waveguide core strongly dependent on the bias voltage: when the current decreases from the peak to the valley there is an increase of the electric field across the depleted core. The electric field enhancement in the core-depleted layer causes the Franz-Keldysh absorption band-edge to red shift, which is responsible for the electroabsorption effect. High frequency ac signals as low as 100 mV can induce electric field high speed switching, producing substantial light modulation (up to 15 dB) at photon energies slightly lower than the waveguide core band-gap energy. The k...

Figueiredo, J M L; Stanley, C R

2002-01-01T23:59:59.000Z

132

Voltage Stability Studies for Southern Company Services  

Science Conference Proceedings (OSTI)

This report describes a study conducted under an EPRI Tailored Collaboration project to develop and demonstrate procedures for the assessment of voltage security of the Southern Electric System (SES). The contractor used EPRI steady-state analysis tools including VSTAB (Voltage STABility assessment program) to assess stability margins and verified them using EPRI dynamic tools including ETMSP (Extended Transient / Mid-term Stability Program).

1997-12-31T23:59:59.000Z

133

Voltage regulation in linear induction accelerators  

DOE Patents (OSTI)

Improvement in voltage regulation in a Linear Induction Accelerator wherein a varistor, such as a metal oxide varistor when it 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.

Parsons, W.M.

1991-03-19T23:59:59.000Z

134

Voltage regulation in linear induction accelerators  

DOE Patents (OSTI)

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.

Parsons, W.M.

1992-12-29T23:59:59.000Z

135

Method and apparatus for monitoring the rotating frequency of de-energized induction motors  

DOE Patents (OSTI)

The rotational speed of a coasting induction motor is measured by sensing e residual electrical voltages at the power terminals of the motor, thus eliminating the need for conventional tachometer equipment, additional mechanical components or modifications to the induction motor itself. The power terminal voltage signal is detected and transformed into a DC voltage proportional to the frequency of the signal. This DC voltage can be input to the control system of a variable frequency motor controller to regulate the output characteristics thereof relative to the speed of the coasting motor.

Mikesell, Harvey E. (McMurray, PA); Lucy, Eric (Murrysville, PA)

1998-01-01T23:59:59.000Z

136

Method and apparatus for monitoring the rotating frequency of de-energized induction motors  

DOE Patents (OSTI)

The rotational speed of a coasting induction motor is measured by sensing e residual electrical voltages at the power terminals of the motor, thus eliminating the need for conventional tachometer equipment, additional mechanical components or modifications to the induction motor itself. The power terminal voltage signal is detected and transformed into a DC voltage proportional to the frequency of the signal. This DC voltage can be input to the control system of a variable frequency motor controller to regulate the output characteristics thereof relative to the speed of the coasting motor. 6 figs.

Mikesell, H.E.; Lucy, E.

1998-02-03T23:59:59.000Z

137

NREL: Measurements and Characterization - Current Versus Voltage  

NLE Websites -- All DOE Office Websites (Extended Search)

Current Versus Voltage Current Versus Voltage The National Renewable Energy Laboratory (NREL) Device Performance group uses current versus voltage (I-V) measurement systems to assess the main performance parameters for photovoltaic (PV) cells and modules. I-V measurement systems determine the output performance of devices, including: open-circuit voltage (Voc), short-circuit current (Isc), fill factor (FF), maximum power output of the device (Pmax), voltage at maximum power (Vmax), current at maximum power (Imax), and conversion efficiency of the device (η). Some I-V systems may also be used to perform dark I-V measurements to determine diode properties and series and shunt resistances. We use three I-V systems to measure performance of individual PV cells; and four for modules - two for measurements under simulated conditions; and

138

High Voltage Safety Act | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

High Voltage Safety Act High Voltage Safety Act High Voltage Safety Act < Back Eligibility Commercial Construction Developer General Public/Consumer Industrial Installer/Contractor Utility Savings Category Alternative Fuel Vehicles Hydrogen & Fuel Cells Buying & Making Electricity Water Home Weatherization Solar Wind Program Info State Georgia Program Type Safety and Operational Guidelines Siting and Permitting 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 electric lines by providing that no work shall be done in the vicinity of such lines unless and until the owner or operator thereof has been notified of such work and has taken the appropriate safety measures. The Georgia Public Service Commission requires

139

Flexible method for monitoring fuel cell voltage  

DOE Patents (OSTI)

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.

Mowery, Kenneth D. (Noblesville, IN); Ripley, Eugene V. (Russiaville, IN)

2002-01-01T23:59:59.000Z

140

Corona and Motor Voltage Interim Report  

SciTech Connect

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.

Hsu, J.S.

2005-05-06T23:59:59.000Z

Note: This page contains sample records for the topic "voltage abnormal frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Comparative study of gigahertz CMOS LC quadrature voltage-controlled oscillators with relevance to phase noise  

Science Conference Proceedings (OSTI)

This review paper presents a comparative study of published integrated submicron CMOS quadrature voltage-controlled oscillator designs, based on LC resonator tanks operating at gigahertz frequencies. Although special reference to phase noise reduction ... Keywords: LC tanks, Phase noise, Quadrature VCO, RF CMOS circuits

Owen Casha; Ivan Grech; Joseph Micallef

2007-08-01T23:59:59.000Z

142

Incorporating Voltage Fluctuations of the Power Distribution Network into the Transient Analysis of CMOS Logic Gates  

Science Conference Proceedings (OSTI)

Decreased power supply levels have reduced the tolerance to voltage changes within power distribution networks in CMOS integrated circuits. High on-chip currents, required to charge and discharge large on-chip loads while operating at high frequencies, ... Keywords: IR drops, power distribution network, system-on-a-chip

Kevin T. Tang; Eby G. Friedman

2002-05-01T23:59:59.000Z

143

Automatic Fault Characterization via Abnormality-Enhanced Classification  

Science Conference Proceedings (OSTI)

Enterprise and high-performance computing systems are growing extremely large and complex, employing hundreds to hundreds of thousands of processors and software/hardware stacks built by many people across many organizations. As the growing scale of these machines increases the frequency of faults, system complexity makes these faults difficult to detect and to diagnose. Current system management techniques, which focus primarily on efficient data access and query mechanisms, require system administrators to examine the behavior of various system services manually. Growing system complexity is making this manual process unmanageable: administrators require more effective management tools that can detect faults and help to identify their root causes. System administrators need timely notification when a fault is manifested that includes the type of fault, the time period in which it occurred and the processor on which it originated. Statistical modeling approaches can accurately characterize system behavior. However, the complex effects of system faults make these tools difficult to apply effectively. This paper investigates the application of classification and clustering algorithms to fault detection and characterization. We show experimentally that naively applying these methods achieves poor accuracy. Further, we design novel techniques that combine classification algorithms with information on the abnormality of application behavior to improve detection and characterization accuracy. Our experiments demonstrate that these techniques can detect and characterize faults with 65% accuracy, compared to just 5% accuracy for naive approaches.

Bronevetsky, G; Laguna, I; de Supinski, B R

2010-12-20T23:59:59.000Z

144

Performance of a voltage peak detection-based flickermeter  

Science Conference Proceedings (OSTI)

Voltage fluctuations and rapid voltage changes lead to lamps flickering and disturbance of visual perception may occur consequently. For evaluation of the flicker severity level by means of voltage measurement there was developed an instrument called ... Keywords: Matlab Simulink, flickermeter, interharmonics, performance analysis, voltage fluctuation, voltage peak detection

Jiri Drapela

2009-12-01T23:59:59.000Z

145

Circuit for monitoring temperature of high-voltage equipment  

DOE Patents (OSTI)

This invention relates to an improved circuit for measuring temperature in a region at high electric potential and generating a read-out of the same in a region at lower potential. The circuit is specially designed to combine high sensitivity, stability, and accuracy. A major portion of the circuit situated in the high-potential region can take the form of an integrated circuit. The preferred form of the circuit includes an input section which is situated in the high-potential region and comprises a temperature-compensated thermocouple circuit for sensing temperature, an oscillator circuit for generating a train of ramp voltages whose rise time varies inversely with the thermocouple output, a comparator and switching circuit for converting the oscillator output to pulses whose frequency is proportional to the thermocouple output, and a light-emitting diode which is energized by these pulses. An optical coupling transmits the light pulses generated by the diode to an output section of the circuit, situated in a region at ground. The output section comprises means for converting the transmitted pulses to electrical pulses of corresponding frequency, means for amplifying the electrical pulses, and means for displaying the frequency of the same. The preferred embodiment of the overall circuit is designed so that the frequency of the output signal in hertz and tenths of hertz is equal to the sensed temperature in degrees and tenths of degrees.

Jacobs, Martin E. (Chillicothe, OH)

1976-01-01T23:59:59.000Z

146

Voltage controlled spintronics device for logic applications.  

SciTech Connect

We consider logic device concepts based on our previously proposed spintronics device element whose magnetization orientation is controlled by application of a bias voltage instead of a magnetic field. The basic building block is the voltage-controlled rotation (VCR) element that consists of a four-layer structure--two ferromagnetic layers separated by both nanometer-thick insulator and metallic spacer layers. The interlayer exchange coupling between the two ferromagnetic layers oscillates as a function of applied voltage. We illustrate transistor-like concepts and re-programmable logic gates based on VCR elements.

Bader, S. D.; You, C.-Y.

1999-09-03T23:59:59.000Z

147

Voltage controlled spintronic devices for logic applications  

SciTech Connect

We consider logic device concepts based on our previously proposed spintronics device element whose magnetization orientation is controlled by application of a bias voltage instead of a magnetic field. The basic building block is the voltage-controlled rotation (VCR) element that consists of a four-layer structure--two ferromagnetic layers separated by both nanometer-thick insulator and metallic spacer layers. The interlayer exchange coupling between the two ferromagnetic layers oscillates as a function of applied voltage. We illustrate transistorlike concepts and reprogrammable logic gates based on VCR elements. (c) 2000 American Institute of Physics.

You, Chun-Yeol [Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Bader, S. D. [Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

2000-05-01T23:59:59.000Z

148

Interphase power controller with voltage injection  

Science Conference Proceedings (OSTI)

This paper introduces a new family of Interphase Power Controllers (IPC) based on the principle of voltage injection commonly used in phase-shifting transformers (PST). The voltage injection IPC exhibits power (active and reactive) control characteristics similar to previously defined IPC's and retains their inherent qualities: passive control, short circuit limitation and voltage decoupling. It also provides more flexibility for the adjustment of the operating points. Two promising topologies are described in more detail. One of them offers the potential of retrofitting existing phase-shifting transformers into full-fledged IPC's.

Beauregard, F.; Brochu, J.; Morin, G.; Pelletier, P. (Centre d'Innovation sur le Transport d'Energie du Quebec, Varennes, Quebec (Canada))

1994-10-01T23:59:59.000Z

149

Time and Frequency Portal  

Science Conference Proceedings (OSTI)

NIST Home > Time and Frequency Portal. Time and Frequency Portal. Programs and Projects. CODATA values of the fundamental constants ...

2013-06-27T23:59:59.000Z

150

High-frequency electric field measurement using a toroidal antenna  

DOE Patents (OSTI)

A simple and compact method and apparatus for detecting high frequency electric fields, particularly in the frequency range of 1 MHz to 100 MHz, uses a compact toroidal antenna. For typical geophysical applications the sensor will be used to detect electric fields for a wide range of spectrum starting from about 1 MHz, in particular in the frequency range between 1 to 100 MHz, to detect small objects in the upper few meters of the ground. Time-varying magnetic fields associated with time-varying electric fields induce an emf (voltage) in a toroidal coil. The electric field at the center of (and perpendicular to the plane of) the toroid is shown to be linearly related to this induced voltage. By measuring the voltage across a toroidal coil one can easily and accurately determine the electric field.

Lee, Ki Ha (Lafayette, CA)

2002-01-01T23:59:59.000Z

151

Low voltage arc formation in railguns  

DOE Patents (OSTI)

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.

Hawke, R.S.

1985-08-05T23:59:59.000Z

152

Low voltage arc formation in railguns  

DOE Patents (OSTI)

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.

Hawke, Ronald S. (Livermore, CA)

1987-01-01T23:59:59.000Z

153

Low voltage arc formation in railguns  

DOE Patents (OSTI)

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.

Hawke, R.S.

1987-11-17T23:59:59.000Z

154

High-voltage-compatible, fully depleted CCDs  

SciTech Connect

We describe charge-coupled device (CCD) developmentactivities at the Lawrence Berkeley National Laboratory (LBNL).Back-illuminated CCDs fabricated on 200-300 mu m thick, fully depleted,high-resistivity silicon substrates are produced in partnership with acommercial CCD foundry.The CCDs are fully depleted by the application ofa substrate bias voltage. Spatial resolution considerations requireoperation of thick, fully depleted CCDs at high substrate bias voltages.We have developed CCDs that are compatible with substrate bias voltagesof at least 200V. This improves spatial resolution for a given thickness,and allows for full depletion of thicker CCDs than previously considered.We have demonstrated full depletion of 650-675 mu m thick CCDs, withpotential applications in direct x-ray detection. In this work we discussthe issues related to high-voltage operation of fully depleted CCDs, aswell as experimental results on high-voltage-compatible CCDs.

Holland, Stephen E.; Bebek, Chris J.; Dawson, Kyle S.; Emes, JohnE.; Fabricius, Max H.; Fairfield, Jessaym A.; Groom, Don E.; Karcher, A.; Kolbe, William F.; Palaio, Nick P.; Roe, Natalie A.; Wang, Guobin

2006-05-15T23:59:59.000Z

155

Property:Nominal Voltage | Open Energy Information  

Open Energy Info (EERE)

Nominal Voltage Nominal Voltage Jump to: navigation, search Property Name Nominal Voltage Property Type Number This is a property of type Number. Pages using the property "Nominal Voltage" Showing 22 pages using this property. D Distributed Generation Study/10 West 66th Street Corp + 480 + Distributed Generation Study/615 kW Waukesha Packaged System + 480 + Distributed Generation Study/Aisin Seiki G60 at Hooligans Bar and Grille + 240 + Distributed Generation Study/Arrow Linen + 480 + Distributed Generation Study/Dakota Station (Minnegasco) + 0 + Distributed Generation Study/Elgin Community College + 4,160 + Distributed Generation Study/Emerling Farm + 480 + Distributed Generation Study/Floyd Bennett + 480 + Distributed Generation Study/Harbec Plastics + 480 +

156

Assessment of Voltage Security Methods and Tools  

Science Conference Proceedings (OSTI)

To ensure voltage-secure operation of a power system, VAR control devices must be optimally placed and operated. This project assessed tools and methods that claim to help utilities meet these needs and recommended specific enhancements to these tools.

1995-10-26T23:59:59.000Z

157

Superconducting Low Voltage Direct Current (LVDC) Networks  

Science Conference Proceedings (OSTI)

A low voltage dc superconducting distribution network is a challenging future opportunity for power distribution. This report presents a scheme for a superconducting, parallel- connected, multiterminal dc transmission system.

1994-04-27T23:59:59.000Z

158

System for increasing corona inception voltage of insulating oils  

DOE Patents (OSTI)

The Corona Inception Voltage of insulating oils is increased by repetitive cycles of prestressing the oil with a voltage greater than the corona inception voltage, and either simultaneously or serially removing byproducts of corona by evacuation and heating the oil.

Rohwein, Gerald J. (Albuquerque, NM)

1998-01-01T23:59:59.000Z

159

Quantification of abnormal intracranial pressure waves and isotope cisternography for diagnosis of occult communicating hydrocephalus  

SciTech Connect

Nineteen consecutive patients with suspected occult communicating hydrocephalus were investigated by means of clinical evaluation, neuropsychological testing, isotope cisternography, computed tomography scanning, and continuous intracranial pressure monitoring. Semi-quantitative grading systems were used in the evaluation of the clinical, neuropsychological, and cisternographic assessments. Clinical examination, neuropsychological testing, and computed tomography scanning were repeated 3 months after ventriculoperitoneal shunting. All patients showed abnormal intracranial pressure waves and all improved after shunting. There was close correlation between number, peak, and pulse pressures of B waves and the mean intracranial pressure. However, quantification of B waves by means of number, frequency, and amplitude did not help in predicting the degree of clinical improvement postshunting. The most sensitive predictor of favorable response to shunting was enlargement of the temporal horns on computed tomography scan. Furthermore, the size of temporal horns correlated with mean intracranial pressure. There was no correlation between abnormalities on isotope cisternography and clinical improvement.

Cardoso, E.R.; Piatek, D.; Del Bigio, M.R.; Stambrook, M.; Sutherland, J.B.

1989-01-01T23:59:59.000Z

160

Spark gap with low breakdown voltage jitter  

SciTech Connect

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.

Rohwein, Gerald J. (Albuquerque, NM); Roose, Lars D. (Albuquerque, NM)

1996-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "voltage abnormal frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Voltage Control Optimization to Improve Transmission Efficiency  

Science Conference Proceedings (OSTI)

An optimal power flow solution is unique from a conventional power flow solution in that an objective function and user-specified constraints are enforced and satisfied to reach a valid solution. This report presents an analytical study on the optimization of power flow in order to minimize reactive power losses via the modification of generator voltage schedules and transmission switched shunt status. The study examines the potential benefits and applicability of near-real-time voltage control ...

2012-11-08T23:59:59.000Z

162

Monte Carlo Potts Investigation of Dynamic Abnormal Grain Growth  

Science Conference Proceedings (OSTI)

A behavior akin to dynamic abnormal grain growth has been found to occur in model results using small strain rates to achieve modest recrystallization rates.

163

Modular high voltage power supply for chemical analysis  

DOE Patents (OSTI)

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

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

2007-01-09T23:59:59.000Z

164

Modular high voltage power supply for chemical analysis  

DOE Patents (OSTI)

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

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

2008-07-15T23:59:59.000Z

165

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

E-Print Network (OSTI)

This thesis presents a thorough analysis of saddle-node bifurcations for power system dynamic models, including a third order representation of high voltage direct current (HVDC) transmission, classic ac generator dynamics with reactive flows, and voltage and frequency dependent load models. Extensions of the Point of Collapse and Continuation methods, initially used in ac system voltage stability studies, are applied to the determination of these bifurcation points. These methods are compared and used for calculating bus voltage profiles (“nose ” curves) and collapse points on ac/dc systems of up to 2158 buses, considering a variety of operational limits and controls, namely, ac/dc regulating transformer tap limits, voltage and reactive power limits, and area interchange control. AC generator reactive power limits, HVDC firing angle limits and voltage dependent current order limits (VDCOL) are shown to affect the stability and loadability of these systems. A vector Lyapunov function approach is employed to define a system wide energy function that can be used for stability analysis. This thesis describes the derivation

Claudio A. Cañizares

1991-01-01T23:59:59.000Z

166

Cell Voltage Noise Reduction Based on Wavelet in Aluminum ...  

Science Conference Proceedings (OSTI)

Presentation Title, Cell Voltage Noise Reduction Based on Wavelet in Aluminum ... cell voltage signals collected in aluminium electrolysis process are with high ...

167

Dynamic Simulation of Cell Voltage Resonance Effect in Aluminum ...  

Science Conference Proceedings (OSTI)

Dubal Cell Voltage Drop Initiatives towards Low Energy High Amperage Cells · Dynamic Simulation of Cell Voltage Resonance Effect in Aluminum Electrolysis ...

168

Appendix C: California ISO Real Time Voltage Security Assessment...  

NLE Websites -- All DOE Office Websites (Extended Search)

C: California ISO Real Time Voltage Security Assessment (VSA) Prototype Functional SpecificationsPrototype Development Title Appendix C: California ISO Real Time Voltage Security...

169

Appendix B: California ISO Real Time Voltage Security Assessment...  

NLE Websites -- All DOE Office Websites (Extended Search)

B: California ISO Real Time Voltage Security Assessment (VSA) Summary Report Title Appendix B: California ISO Real Time Voltage Security Assessment (VSA) Summary Report Publication...

170

Appendix A: California ISO Real Time Voltage Security Assessment...  

NLE Websites -- All DOE Office Websites (Extended Search)

A: California ISO Real Time Voltage Security Assessment (VSA) Project: Summary of Survey Results on Methodologies for use in Real-Time Voltage Security Assessment Title Appendix A:...

171

Green Island Power Authority Transmission Voltage Support System...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Green Island Power Authority Transmission Voltage Support System Project Green Island Power Authority Transmission Voltage Support System Project Power point presentation...

172

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

DOE Patents (OSTI)

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.

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

1987-07-30T23:59:59.000Z

173

System for transmitting low frequency analog signals over AC power lines  

DOE Patents (OSTI)

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 in 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.

Baker, Steven P. (Powell, TN); Durall, Robert L. (Lenoir City, TN); Haynes, Howard D. (Knoxville, TN)

1989-01-01T23:59:59.000Z

174

Surveillance Guide - OPS 9.6 Investigation of Abnormal Events  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

INVESTIGATION OF ABNORMAL EVENTS INVESTIGATION OF ABNORMAL EVENTS 1.0 Objective The objective of this surveillance is to verify that contractor personnel are effectively investigating abnormal events. The activities included in this surveillance provide a basis for determining whether the contractor has implemented a thorough review process to identify, investigate, and resolve abnormal events. The surveillance also provides a basis for ensuring that applicable DOE requirements are implemented. 2.0 References 2.1 DOE 5480.19, Conduct of Operations Requirements for DOE Facilities 2.2 DOE-STD-1045-93, Guide To Good Practices for Notifications and Investigations of Abnormal Events 2.3 DOE 232.1A, Occurrence Reporting and Processing of Operations Information 3.0 Requirements Implemented

175

A radio frequency coaxial feedthrough  

DOE Patents (OSTI)

An improved radio frequency coaxial transmission line vacuum feedthrough is provided based on the use of a half-wavelength annular dielectric pressure barrier disk, or multiple disks comprising an effective half wavelength structure to eliminate reflection from the barrier surfaces. Gas-tight seals are formed about the outer and inner diameter surfaces of the barrier disk using a sealing technique which generates radial forces sufficient to form seals by forcing the conductor walls against the surfaces of the barrier disks in a manner which does not deform the radii of the inner and outer conductors, thereby preventing enhancement of the electric field at the barrier faces which limits the voltage and power handling capabilities of a feedthrough.

Owens, T.L.

1987-12-07T23:59:59.000Z

176

Analog Integrated Circuits and Signal Processing, 42, 231–238, 2005 c ? 2005 Springer Science + Business Media, Inc. Manufactured in The Netherlands. Cascode Monolithic DC-DC Converter for Reliable Operation at High Input Voltages  

E-Print Network (OSTI)

Abstract. A cascode bridge circuit for monolithic switching DC-DC converters operating at high input voltages is proposed in this paper. The proposed circuit can also be used as an I/O buffer to interface circuits operating at significantly different voltages. The circuit technique permits the full integration of the active and passive devices of a switching DC-DC converter with a high voltage conversion ratio in a standard low voltage CMOS technology. The cascode bridge structure guarantees the reliable operation of deep submicrometer MOSFETs without exposure to high voltage stress while operating at high input and output voltages. With the proposed circuit technique, steady-state voltage differences between the terminals of all of the MOSFETs in a switching DC-DC converter are maintained within a range imposed by a target low voltage CMOS technology. High-to-low DC-DC converters operating at input voltages up to three times as high as the maximum voltage that can be directly applied across the terminals of a MOSFET are described. An efficiency of 79.6 % is achieved for 5.4 volts to 0.9 volts conversion assuming a 0.18 µm CMOS technology. The DC-DC converter operates at a switching frequency of 97 MHz while supplying a DC current of 250 mA to the load. Key Words: low voltage DC-DC converters, monolithic voltage regulators, low voltage CMOS technology, MOSFET reliability issues, high voltage stress 1.

Volkan Kursun; Siva G. Narendra; Vivek K. De; Eby G. Friedman

2004-01-01T23:59:59.000Z

177

An accurate continuous calibration system for high voltage current transformer  

SciTech Connect

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.

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

178

Cascode buffer for monolithic voltage conversion operating at high input supply voltages  

E-Print Network (OSTI)

A high-to-low switching DC-DC converter that operates at input supply voltages up to two times as high as the maximum voltage permitted in a nanometer CMOS technology is proposed in this paper. The circuit technique is based on a cascode bridge that maintains the steady-state voltage differences among the terminals of all of the transistors within a range imposed by a specific fabrication technology. The proposed circuit technique permits the full integration of active and passive devices of a switching DC-DC converter with a high voltage conversion ratio in a standard low voltage CMOS process. An efficiency of 87.8 % is achieved for 3.6 volts to 0.9 volts conversion assuming

Volkan Kursun; Gerhard Schrom; Vivek K. De; Eby G. Friedman; Siva G. Narendra

2005-01-01T23:59:59.000Z

179

An Electronic Voltage Transformer Based on WLAN Technology  

Science Conference Proceedings (OSTI)

An electronic voltage transformer based on WLAN technology is developed for adapting to the development trends of substations’ synthesis automation. The transformer is composed of voltage-to-current conversion unit, signal processing unit and data ... Keywords: electronic voltage transformer, voltage-to-current conversion, WLAN technology, digital interface, wireless communication

Jianqin Feng; Qingming Wang; Fen Niu; Guangzhao Cui; Anping Zheng

2010-03-01T23:59:59.000Z

180

Motor voltage high harmonics influence to efficient energy usage  

Science Conference Proceedings (OSTI)

Analysis of the effect of non-sinusoidal voltages on the three-phase induction motor is presented in the paper. When the induction motors are supplied by a rectangular shape of the voltage inverter with high levels of harmonic voltage (Uh,i ... Keywords: energy efficiency, harmonics, induction motor, non-sinusoidal voltage, power losses

Miloje M. Kostic; Branka B. Kostic

2011-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "voltage abnormal frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Distribution System Voltage Performance Analysis for High-Penetration Photovoltaics  

DOE Green Energy (OSTI)

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

Liu, E.; Bebic, J.

2008-02-01T23:59:59.000Z

182

Optimal Compensation Algorithms for a Dynamic Voltage Restorer  

Science Conference Proceedings (OSTI)

The Dynamic Voltage Restorer (DVR) as an electronics based custom device, is used to protect sensitive loads from the voltage sags in the power distribution system. With the rapid technology advancement in industrial control processes, it is experiencing ... Keywords: Dynamic Voltage Restorer (DVR), power quality, voltage sag, Zero Active Power Compensation (ZAPC), Minimal Active Power Compensation (MAPC)

Deng Pan; Chen Zhongming; Jiang Peng; Abdelkrim Benchaib; Guillaume De Preville

2010-06-01T23:59:59.000Z

183

Analysis of Voltage Rise Effect on Distribution Network with Distributed  

E-Print Network (OSTI)

appearance of hidden loads and affect the voltage profile of low voltage distribution network. To overcomeAnalysis of Voltage Rise Effect on Distribution Network with Distributed Generation M. A. Mahmud. This paper presents a detail analysis of how does voltage rise on distribution network due to the penetration

Pota, Himanshu Roy

184

Developments in line-voltage thermostats  

Science Conference Proceedings (OSTI)

A thermostat that provides reliable, accurate temperature control is the key to a comfortable, efficient space-heating system. The lack of a commercially available line-voltage thermostat that is affordable and performs well has been a significant factor in limiting the comfort and popularity of zoned residential electric heating systems. With EPRI support, two manufacturers have developed innovative, electronics-based line-voltage thermostats that offer a cost-effective control option for creating a comfortable environment with zoned electric heat. These thermostats also may help reduce energy consumption.

Kesselring, J.

1992-09-01T23:59:59.000Z

185

Electronic circuit for measuring series connected electrochemical cell voltages  

DOE Patents (OSTI)

An electronic circuit for measuring voltage signals in an energy storage device is disclosed. The electronic circuit includes a plurality of energy storage cells forming the energy storage device. A voltage divider circuit is connected to at least one of the energy storage cells. A current regulating circuit is provided for regulating the current through the voltage divider circuit. A voltage measurement node is associated with the voltage divider circuit for producing a voltage signal which is proportional to the voltage across the energy storage cell.

Ashtiani, Cyrus N. (West Bloomfield, MI); Stuart, Thomas A. (Toledo, OH)

2000-01-01T23:59:59.000Z

186

Method of detecting system function by measuring frequency response  

Science Conference Proceedings (OSTI)

Real-time battery impedance spectrum is acquired using a one-time record. Fast Summation Transformation (FST) is a parallel method of acquiring a real-time battery impedance spectrum using a one-time record that enables battery diagnostics. An excitation current to a battery is a sum of equal amplitude sine waves of frequencies that are octave harmonics spread over a range of interest. A sample frequency is also octave and harmonically related to all frequencies in the sum. The time profile of this signal has a duration that is a few periods of the lowest frequency. The voltage response of the battery, average deleted, is the impedance of the battery in the time domain. Since the excitation frequencies are known and octave and harmonically related, a simple algorithm, FST, processes the time record by rectifying relative to the sine and cosine of each frequency. Another algorithm yields real and imaginary components for each frequency.

Morrison, John L. (Butte, MT); Morrison, William H. (Manchester, CT); Christophersen, Jon P. (Idaho Falls, ID)

2012-04-03T23:59:59.000Z

187

High frequency limit for single-electron pumping operations  

E-Print Network (OSTI)

In this Letter, we study the transient electron transfer phenomena of single-electron devices with alternating external gate voltages. We obtain a high frequency limit for pumping electrons one at a time in single-electron devices. Also, we find that in general the electrical current is not proportional to the frequency of the external signals in the single-electron devices, due to the strong quantum coherence tunneling effect.

Chuan-Yu Lin; Wei-Min Zhang

2010-12-04T23:59:59.000Z

188

Group 3: Humidity, Temperature and Voltage (Presentation)  

SciTech Connect

This is a summary of the work of Group 3 of the International PV QA Task Force. 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.

Wohlgemuth, J.

2013-09-01T23:59:59.000Z

189

High voltage VLF testing of power cables  

SciTech Connect

This publication describes a laboratory test program conducted with the objective to develop a test that would replace the existing dc withstand test. The article describes the methodology used to establish the voltage duration and magnitude of VLF (0.1 Hz) high voltage field tests suitable for crosslinked polyethylene (XLPE) insulated power cable. The results show that the voltage breakdown of laboratory aged XLPE cable at 0.1 Hz is approximately equal to that at 60 Hz, that proof tests at 0.1 Hz is approximately equal to that at 60 Hz, that proof tests at 0.1 Hz cause very little damage to the cable, and that 0.1 Hz testing appears to be a satisfactory alternate to dc testing. Preliminary values are suggested for voltage magnitude and time duration of cable acceptance, maintenance and proof tests at 0.1 Hz for XLPE cable rated up to 35 kV. A program is underway to similarly evaluate samples of service-aged XLPE cable; as well as to demonstrate the use of the preliminary test values at typical utility installations.

Eager, G.S.; Katz, C.; Fryszczyn, B. [Cable Technology Labs., Inc., New Brunswick, NJ (United States); Densley, J. [Ontario Hydro, Toronto, Ontario (Canada); Bernstein, B.S. [EPRI, Washington, DC (United States)

1997-04-01T23:59:59.000Z

190

High Frequency Effects of Variable Frequency Drives (VFD) on Electrical Submersible Pump (ESP) Systems  

E-Print Network (OSTI)

Variable frequency drives (VFD) and subsea (umbilical) cables are frequently used in electrical submersible pump (ESP) systems for offshore platforms. There are two basic system configurations for ESP systems; VFD can be installed on the platform and the motor is connected to it through an umbilical cable, and VFD and the motor are installed closely and they are connected to the system through an umbilical cable. In this thesis, the pros and cons of each configuration are mentioned, but the focus is on the system with a VFD controlled motor through a long umbilical cable. A 36-pulse VFD is studied. Since multilevel VFDs have high frequency harmonics, high frequency modeling of the umbilical cable is used, and skin effect is also taken into consideration in the cable. The effect of the interactions between the umbilical cable and high frequency harmonics on the motor terminal voltage is explored.

Ozkentli, Esra

2012-08-01T23:59:59.000Z

191

ESP-The Electrical submersible pump. Part 7. Applying variable frequency drives to ESPs  

SciTech Connect

To keep pace with technology, the oil industry has begun using variable frequency drives on electrical submersible pumps. Applying variable frequency drives on ESPs began seriously in 1977. In March 1983, there were approximately 350 variable frequency drives successfully operating on electrical submersible pumps throughout the world. Three types of variable frequency drives available today are the current source inverter, the pulse width modulation, and the variable voltage source inverter. As all three types have good points and bad, a short discussion of each type is essential to understand why the variable voltage inverter is used most often in oil field applications and why it has been a success. A current source inverter typically uses a phasecontrolled rectifier to generate variable DC current. The phase-controlled rectifier produces the required current which is subsequently filtered by a DC link reactor. The inverter then produces the desired variable frequency current and the motor voltage varies with load.

Watson, A.J.

1983-11-15T23:59:59.000Z

192

Accurate Automated Detection of Autism Related Corpus Callosum Abnormalities  

Science Conference Proceedings (OSTI)

The importance of accurate early diagnostics of autism that severely affects personal behavior and communication skills cannot be overstated. Neuropathological studies have revealed an abnormal anatomy of the Corpus Callosum (CC) in autistic brains. ... Keywords: Autism, Corpus callosum, Modeling, Segmentation

Ayman El-Baz; Ahmed Elnakib; Manuel F. Casanova; Georgy Gimel'Farb; Andrew E. Switala; Desha Jordan; Sabrina Rainey

2011-10-01T23:59:59.000Z

193

Abnormal Negative Sequence Analysis Excel Application Version 1.0  

Science Conference Proceedings (OSTI)

The Abnormal Negative Sequence Analysis Excel Application can be used to estimate the likely impact of any electrical event on the generator rotor so that a quick informed decision can be made about generator rotor inspection. This project is intended to develop an Excel based application that can be used for assessing the need for turbine generators to be inspected after an abnormal negative sequence or motoring from standstill event may have occurred. Microsoft2000, XP, and Vista running either Micros...

2010-11-29T23:59:59.000Z

194

Extremely high frequency RF effects on electronics.  

SciTech Connect

The objective of this work was to understand the fundamental physics of extremely high frequency RF effects on electronics. To accomplish this objective, we produced models, conducted simulations, and performed measurements to identify the mechanisms of effects as frequency increases into the millimeter-wave regime. Our purpose was to answer the questions, 'What are the tradeoffs between coupling, transmission losses, and device responses as frequency increases?', and, 'How high in frequency do effects on electronic systems continue to occur?' Using full wave electromagnetics codes and a transmission-line/circuit code, we investigated how extremely high-frequency RF propagates on wires and printed circuit board traces. We investigated both field-to-wire coupling and direct illumination of printed circuit boards to determine the significant mechanisms for inducing currents at device terminals. We measured coupling to wires and attenuation along wires for comparison to the simulations, looking at plane-wave coupling as it launches modes onto single and multiconductor structures. We simulated the response of discrete and integrated circuit semiconductor devices to those high-frequency currents and voltages, using SGFramework, the open-source General-purpose Semiconductor Simulator (gss), and Sandia's Charon semiconductor device physics codes. This report documents our findings.

Loubriel, Guillermo Manuel; Vigliano, David; Coleman, Phillip Dale; Williams, Jeffery Thomas; Wouters, Gregg A.; Bacon, Larry Donald; Mar, Alan

2012-01-01T23:59:59.000Z

195

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

E-Print Network (OSTI)

Electric quality problems associated with power interactions between distribution and industrial process control systems can be prevented. Surveys of large users that buy power at the transmission and distribution voltages turn up relatively few complaints about the quality of their incoming power, while surveys of small users connected at secondary voltages tum up numerous complaints about the quality of their incoming power. Three major changes in the characteristics of customer loads and power distribution systems have altered the nature of the power quality equation: (I) greater sensitivity of devices and equipment to electric power variations, (2) the interconnection of sensitive loads in extensive networks and automated processes, and (3) 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 equipment in an oil refinery. Unlike conventional transformers, the CVT or ferro-resonant transformer allows the core to become saturated with magnetic flux, which maintains a relatively constant output voltage during input voltage variations such as undervoltages, overvoltages, and harmonic distortion.

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

2000-04-01T23:59:59.000Z

196

Electrical system architecture having high voltage bus  

DOE Patents (OSTI)

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

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

2011-03-22T23:59:59.000Z

197

Sacramento Area Voltage Support Environmental Impact Statement  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

E E R R A N E V A D A R E G I O N Sacramento Area Voltage Support DRAFT ENVIRONMENTAL IMPACT STATEMENT DRAFT ENVIRONMENTAL IMPACT STATEMENT DOE/EIS-0323 NOVEMBER 2002 COVER SHEET Title: Sacramento Area Voltage Support Draft Environmental Impact Statement (EIS) Lead Agency: Western Area Power Administration (Western) Location: Alameda, Contra Costa, Placer, Sacramento, San Joaquin, and Sutter Counties, State of California. EIS Number: DOE/EIS-0323 Contact: Ms. Loreen McMahon, Environmental Project Manager Western Area Power Administration Sierra Nevada Region 114 Parkshore Drive Folsom, CA 95630 (916) 353-4460 (916) 985-1936 fax email: mcmahon@wapa.gov Website: Information is also available on our website: www.wapa.gov Hotline: 1-877-913-4440 (toll-free) Abstract The Western Area Power Administration's Central Valley Project transmission system forms an integral part of

198

LOW VOLTAGE 14 Mev NEUTRON SOURCE  

DOE Patents (OSTI)

An apparatus yielding high-energy neutrons at the rate of 10/sup 8/ or more per second by the D,T or D,D reactions is described. The deuterium gas filling is ionized by electrons emitted from a filament, and the resulting ions are focused into a beam and accelerated against a fixed target. The apparatus is built in accordance with the relationship V/sub s/ = A--B log pd, where V/sub s/ is the sparking voltage, p the gas pressure, and d the gap length between the high voltage electrodes. Typical parameters to obtain the high neutron yields are 55 to 80 kv, 0.5 to 7.0 ma beam current, 5 to 12 microns D/sub 2/, and a gap length of 1 centimeter.

Little, R.N. Jr.; Graves, E.R.

1959-09-29T23:59:59.000Z

199

Low Swing Dual Threshold Voltage Domino Logic  

E-Print Network (OSTI)

A low swing domino logic technique is proposed to decrease power consumption without sacrificing noise immunity. With the proposed low swing domino logic circuit technique, active power consumption is reduced by up to 9.4% while improving the noise immunity by 2.6% as compared to standard domino logic circuits. It is also shown that by applying a low swing contention reduction technique, the power savings can be further increased by 6.7% while the delay can be improved by 8.6%. A simple and efficient dual threshold voltage (dual-V t ) circuit technique that incorporates low swing signals is also proposed. It is shown that the proposed dual-V technique reduces the standby leakage current by approximately 235 times while offering enhanced delay characteristics as compared to a standard low threshold voltage implementation.

Volkan Kursun; Eby G. Friedman

2002-01-01T23:59:59.000Z

200

HIGH VOLTAGE, HIGH CURRENT SPARK GAP SWITCH  

DOE Patents (OSTI)

A high voltage and current spark gap switch comprising two main electrodes insulatingly supported in opposed spaced relationship and a middle electrode supported medially between the main electrodes and symmetrically about the median line of the main electrodes is described. The middle electrode has a perforation aligned with the median line and an irradiation electrode insulatingly supported in the body of the middle electrode normal to the median line and protruding into the perforation. (AEC)

Dike, R.S.; Lier, D.W.; Schofield, A.E.; Tuck, J.L.

1962-04-17T23:59:59.000Z

Note: This page contains sample records for the topic "voltage abnormal frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Low-Voltage Cable Aging Management Guidance  

Science Conference Proceedings (OSTI)

This report, intended for use by power plant engineers and craft and administrative personnel who are responsible for cable system aging management, provides guidance on the effective and efficient application of current information and techniques related to aging and condition monitoring (CM) of low-voltage cables. The identification of cables that are prone to early aging and the timely replacement or repair of cables that are degraded will minimize unnecessary power losses, unplanned shutdowns, ...

2013-12-23T23:59:59.000Z

202

A compact high voltage pulse generator  

SciTech Connect

A compact, easily transportable, pulse generator has been developed for a variety of applications that require a pulse duration in the range of 1 {mu} sec., voltages from 150 to 300 KV and current levels from 2,000 to 3,000 amps. The generator has a simple cylindrical configuration and modular construction to facilitate assembly and service. The generator may be operated single-pulse or repetitively at pulse repetition rates to 50 Hz in a burst mode.

Rohwein, G.J.; Babcock, S.R.

1994-07-01T23:59:59.000Z

203

Electro-optic voltage sensor head  

DOE Patents (OSTI)

The invention is an electro-optic voltage sensor head designed for integration with existing types of high voltage transmission and distribution apparatus. The sensor head contains a transducer, which comprises a transducing material in which the Pockels electro-optic effect is observed. In the practice of the invention at least one beam of electromagnetic radiation is routed into the transducing material of the transducer in the sensor head. The beam undergoes an electro-optic effect in the sensor head when the transducing material is subjected to an E-field. The electro-optic effect is observed as a differential phase a shift, also called differential phase modulation, of the beam components in orthogonal planes of the electromagnetic radiation. In the preferred embodiment the beam is routed through the transducer along an initial axis and then reflected by a retro-reflector back substantially parallel to the initial axis, making a double pass through the transducer for increased measurement sensitivity. The preferred embodiment of the sensor head also includes a polarization state rotator and at least one beam splitter for orienting the beam along major and minor axes and for splitting the beam components into two signals which are independent converse amplitude-modulated signals carrying E-field magnitude and hence voltage information from the sensor head by way of optic fibers.

Crawford, Thomas M. (Idaho Falls, ID); Davidson, James R. (Idaho Falls, ID); Woods, Gregory K. (Cornelius, OR)

1999-01-01T23:59:59.000Z

204

Electro-optic voltage sensor head  

DOE Patents (OSTI)

The invention is an electro-optic voltage sensor head designed for integration with existing types of high voltage transmission and distribution apparatus. The sensor head contains a transducer, which comprises a transducing material in which the Pockels electro-optic effect is observed. In the practice of the invention at least one beam of electromagnetic radiation is routed into the transducing material of the transducer in the sensor head. The beam undergoes an electro-optic effect in the sensor head when the transducing material is subjected to an E-field. The electro-optic effect is observed as a differential phase a shift, also called differential phase modulation, of the beam components in orthogonal planes of the electromagnetic radiation. In the preferred embodiment the beam is routed through the transducer along an initial axis and then reflected by a retro-reflector back substantially parallel to the initial axis, making a double pass through the transducer for increased measurement sensitivity. The preferred embodiment of the sensor head also includes a polarization state rotator and at least one beam splitter for orienting the beam along major and minor axes and for splitting the beam components into two signals which are independent converse amplitude-modulated signals carrying E-field magnitude and hence voltage information from the sensor head by way of optic fibers. 6 figs.

Crawford, T.M.; Davidson, J.R.; Woods, G.K.

1999-08-17T23:59:59.000Z

205

Physical design with multiple on-chip voltages  

Science Conference Proceedings (OSTI)

Supply voltage is one of the dominant factors that determine the timing performance and power consumption of VLSI chips. For digital systems with a single supply voltage, some logic devices typically operate faster or more frequently than necessary, ...

Chunhong Chen

2002-04-01T23:59:59.000Z

206

Recommended Rest Frequencies  

Science Conference Proceedings (OSTI)

Return to Table of Contents NIST Recommended Rest Frequencies for Observed Interstellar Molecular Microwave Transitions. by Frank J. Lovas. ...

207

Eastern Frequency Response Study  

Science Conference Proceedings (OSTI)

This study was specifically designed to investigate the frequency response of the Eastern Interconnection that results from large loss-of-generation events of the type targeted by the North American Electric Reliability Corp. Standard BAL-003 Frequency Response and Frequency Bias Setting (NERC 2012a), under possible future system conditions with high levels of wind generation.

Miller, N.W.; Shao, M.; Pajic, S.; D'Aquila, R.

2013-05-01T23:59:59.000Z

208

NIST Online Museum of Quantum Voltage Standards, 1990s  

Science Conference Proceedings (OSTI)

... (Artifact 7, Citation: SP Benz, "Superconductor-normal-superconductor junctions for programmable voltage standards," Appl. Phys. Lett., vol. 67, pp. ...

2013-02-28T23:59:59.000Z

209

Activated Sintering, Spark Plasma Sintering and High Voltage ...  

Science Conference Proceedings (OSTI)

Mar 4, 2013 ... Novel Synthesis and Consolidation of Powder Materials : Activated Sintering, Spark Plasma Sintering and High Voltage Electric Discharge ...

210

Dubal Cell Voltage Drop Initiatives towards Low Energy High ...  

Science Conference Proceedings (OSTI)

About this Abstract. Meeting, 2014 TMS Annual Meeting & Exhibition. Symposium , Aluminum Reduction Technology. Presentation Title, DUBAL CELL VOLTAGE ...

211

Temperature Fitting Method Predicting Equidistant Voltage Drop of ...  

Science Conference Proceedings (OSTI)

High Temperature Compression Test to Determine the Anode Paste ... Temperature Fitting Method Predicting Equidistant Voltage Drop of Anode Nod in  ...

212

Development of the Platform-Mounted Dynamic Voltage Restorer (PMDVR)  

Science Conference Proceedings (OSTI)

The uninterrupted supply of electrical power is critical for many commercial utility customers with sensitive loads. A voltage sag of a few cycles could cause loss of many thousands of dollars due to lost production from process stoppage and associated clean-up issues. The Platform Mounted Dynamic Voltage Restorer (PMDVR) is a distribution voltage level device that compensates for changes in supply line voltage to maintain acceptable input power to customers.

1998-12-31T23:59:59.000Z

213

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

SciTech Connect

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

Watson, A.J.

1983-11-15T23:59:59.000Z

214

ACCELERATED AGING STUDY OF MACHINE WINDING INSULATION UNDER AC AND HIGH FREQUENCY PULSE VOLTAGE APPLICATION.  

E-Print Network (OSTI)

?? It is common practice to perform accelerated aging with 60 Hz ac to determine the lifetime characteristics of insulation used in the machine. Comparable… (more)

Chalise, Sajal Raj

2010-01-01T23:59:59.000Z

215

System for increasing corona inception voltage of insulating oils  

DOE Patents (OSTI)

The Corona Inception Voltage of insulating oils is increased by repetitive cycles of prestressing the oil with a voltage greater than the corona inception voltage, and either simultaneously or serially removing byproducts of corona by evacuation and heating the oil. 5 figs.

Rohwein, G.J.

1998-05-19T23:59:59.000Z

216

Research of Dynamic Voltage Restorer Based on Repetitive Control Strategy  

Science Conference Proceedings (OSTI)

This paper introduces a dynamic voltage restorer with independent three-phase structure, which is controlled on repetitive control strategy. Computer simulation of the whole repetitive control system is performed by Matlab/Simulink, and the results show ... Keywords: Dynamic Voltage Restorer, Repetitive Control, Voltage Sag

Tianyu Liu

2012-10-01T23:59:59.000Z

217

Distributed Generation Source Stiffness and Its Impact on Voltage Distortion  

Science Conference Proceedings (OSTI)

Distributed generators with loads that create high harmonics can cause excessive voltage distortion. This report's objective was to evaluate under controlled laboratory conditions voltage distortion resulting from application of nonlinear load for three different types of rotary generators and one inverter-based generator. Test results also were used to verify the analytical model for predicting voltage distortion from nonlinear load application.

2001-11-27T23:59:59.000Z

218

Selective compensation of voltage harmonics in grid-connected microgrids  

E-Print Network (OSTI)

1 Selective compensation of voltage harmonics in grid-connected microgrids Mehdi Savaghebia , Juan is proposed for selective compensation of main voltage harmonics in a grid- connected microgrid. The aim level. Keywords Distributed Generator (DG); microgrid; grid-connected; voltage harmonics compensation. 1

Vasquez, Juan Carlos

219

Secondary Control for Voltage Unbalance Compensation in an Islanded Microgrid  

E-Print Network (OSTI)

Secondary Control for Voltage Unbalance Compensation in an Islanded Microgrid Mehdi Savaghebi1 microgrid. The aim of the proposed control approach is to enhance the voltage quality at the point of common unbalance. Keywords-distributed generation; microgrid; secondary control; voltage unbalance compensation I

Vasquez, Juan Carlos

220

check list for those with one abnormal BeLPT  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

CHECK LIST FOR THOSE WHO HAVE HAD, OR WHO IN THE FUTURE CHECK LIST FOR THOSE WHO HAVE HAD, OR WHO IN THE FUTURE HAVE, ONE ABNORMAL BeLPT _____ Fill out the EE-1 and EE-3 and include a copy of any abnormal BeLPT results that you have; review the EE-7 form. _____ Make a copy of the completed forms (one to keep for yourself). _____ Take the original copy of your forms (or mail them) to your nearest EEOICPA Resource Center. If you have already filed these forms, please do not fill them out again, just skip to the next item, below. _____ After you are accepted into the DOL program, choose a clinical center where you want to have your medical examinations. Circle the center you choose. _____ Call the clinical center where you want your medical examinations to be performed. ["I have an abnormal beryllium blood test and I need to get

Note: This page contains sample records for the topic "voltage abnormal frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Excimer laser phototherapy for the dissolution of abnormal growth  

DOE Patents (OSTI)

Removal of abnormal human tissue with reduced thermal damage is achieved by selecting a laser having a wavelength in the order of 290-400 nm, orienting a laser-transmitting glass member toward the abnormal tissue and directing the laser through the glass member at power densities, pulse rates, and times sufficient to cause multiphoton absorption and bond breaking by Coulomb repulsion rather than thermal destruction. The glass member may include a laser beam concentrator provided by a lens or cone at the tissue-treatment end to increase the beam energy per unit area and reduce the treatment area.

Gruen, Dieter M. (Downers Grove, IL); Young, Charles E. (Westmont, IL); Pellin, Michael J. (Naperville, IL)

1987-01-01T23:59:59.000Z

222

Methods and systems for detecting abnormal digital traffic  

DOE Patents (OSTI)

Aspects of the present invention encompass methods and systems for detecting abnormal digital traffic by assigning characterizations of network behaviors according to knowledge nodes and calculating a confidence value based on the characterizations from at least one knowledge node and on weighting factors associated with the knowledge nodes. The knowledge nodes include a characterization model based on prior network information. At least one of the knowledge nodes should not be based on fixed thresholds or signatures. The confidence value includes a quantification of the degree of confidence that the network behaviors constitute abnormal network traffic.

Goranson, Craig A [Kennewick, WA; Burnette, John R [Kennewick, WA

2011-03-22T23:59:59.000Z

223

Triple-phase bone image abnormalities in Lyme arthritis  

Science Conference Proceedings (OSTI)

Arthritis is a frequent manifestation of Lyme disease. Limited triple-phase Tc-99m MDP bone imaging of the wrists and hands with delayed whole-body images was performed in a patient with Lyme arthritis. This demonstrated abnormal joint uptake in the wrists and hands in all three phases, with increased activity seen in other affected joints on delayed whole-body images. These findings are nonspecific and have been previously described in a variety of rheumatologic conditions, but not in Lyme disease. Lyme disease should be considered in the differential diagnosis of articular and periarticular bone scan abnormalities.

Brown, S.J.; Dadparvar, S.; Slizofski, W.J.; Glab, L.B.; Burger, M. (Hahnemann Univ. Hospital, Philadelphia, PA (USA))

1989-10-01T23:59:59.000Z

224

Energy conversion apparatus for supplying variable voltage direct current power to an electrically propelled vehicle  

SciTech Connect

A synchronous machine, operable as both a motor and a generator, is mounted on an electrically powered vehicle, such as a mine shuttle car, and includes a plurality of conductors having connections that are detachably engagable with receptacles of a stationary power bank. Engagement of the conductors with the receptacles supplies variable voltage alternating current power to the machine. The machine is drivingly connected to a flywheel on the vehicle and, operating as a motor, energizes the flywheel to store a preselected amount of mechanical energy. The electrical connection between the vehicle and the power bank is opened after the flywheel has been sufficiently charged. The stored energy in the flywheel is then available to drive the machine as a generator and produce high frequency, three phase, alternating current power. The generated power is transmitted to a full wave silicon controlled rectifier that converts the alternating current power to direct current for powering the traction motors of the vehicle. A variable voltage controller is connected to the rectifier and actuates the rectifier to supply direct current at a selected voltage level. The controller is responsive to an operator foot pedal. By manually depressing the foot pedal to a selected position, the voltage level of the rectified current is controlled. Thus, the speed of the traction motors is adjustable topropel the vehicle at a speed within a given range. After a portion of the energy stored by the flywheel is consumed, the vehicle is returned to the power bank to replenish the energy supply.

Jamison, W.B.; Burr, J.F.

1976-09-07T23:59:59.000Z

225

Capacitively coupled RF voltage probe having optimized flux linkage  

DOE Patents (OSTI)

An RF sensor having a novel current sensing probe and a voltage sensing probe to measure voltage and current. The current sensor is disposed in a transmission line to link all of the flux generated by the flowing current in order to obtain an accurate measurement. The voltage sensor is a flat plate which operates as a capacitive plate to sense voltage on a center conductor of the transmission line, in which the measured voltage is obtained across a resistance leg of a R-C differentiator circuit formed by the characteristic impedance of a connecting transmission line and a capacitance of the plate, which is positioned proximal to the center conductor.

Moore, James A. (Powell, TN); Sparks, Dennis O. (Maryville, TN)

1999-02-02T23:59:59.000Z

226

Demonstration of Commissioning Tests for Extra-High Voltage Cross-Linked Polyethylene Cable Systems at Los Angeles Department of Wat er and Power  

Science Conference Proceedings (OSTI)

Today, utilities are installing an increasing number of cross-linked polyethylene (XLPE) transmission cables with system voltages ranging from 115 kV up to 345 kV. This report summarizes field partial discharge measurements and high-voltage ac commissioning tests performed on a Los Angeles Department of Water and Power (LADWP) 230-kV XLPE transmission cable system. The commissioning tests were performed with a field transportable, variable frequency, series resonant test set at 1.4 times rated voltage.

2002-09-11T23:59:59.000Z

227

Low voltage operation of plasma focus  

SciTech Connect

Plasma foci of compact sizes and operating with low energies (from tens of joules to few hundred joules) have found application in recent years and have attracted plasma-physics scientists and engineers for research in this direction. We are presenting a low energy and miniature plasma focus which operates from a capacitor bank of 8.4 {mu}F capacity, charged at 4.2-4.3 kV and delivering approximately 52 kA peak current at approximately 60 nH calculated circuit inductance. The total circuit inductance includes the plasma focus inductance. The reported plasma focus operates at the lowest voltage among all reported plasma foci so far. Moreover the cost of capacitor bank used for plasma focus is nearly 20 U.S. dollars making it very cheap. At low voltage operation of plasma focus, the initial breakdown mechanism becomes important for operation of plasma focus. The quartz glass tube is used as insulator and breakdown initiation is done on its surface. The total energy of the plasma focus is approximately 75 J. The plasma focus system is made compact and the switching of capacitor bank energy is done by manual operating switch. The focus is operated with hydrogen and deuterium filled at 1-2 mbar.

Shukla, Rohit; Sharma, S. K.; Banerjee, P.; Das, R.; Deb, P.; Prabahar, T.; Das, B. K.; Adhikary, B.; Shyam, A. [Energetics and Electromagnetics Division, Facility for Electromagnetic Systems, Bhabha Atomic Research Center, Visakhapatanam, A.P. 530012 (India)

2010-08-15T23:59:59.000Z

228

High Voltage GaN Schottky Rectifiers  

SciTech Connect

Mesa and planar GaN Schottky diode rectifiers with reverse breakdown voltages (V{sub RB}) up to 550V and >2000V, respectively, have been fabricated. The on-state resistance, R{sub ON}, was 6m{Omega}{center_dot} cm{sup 2} and 0.8{Omega}cm{sup 2}, respectively, producing figure-of-merit values for (V{sub RB}){sup 2}/R{sub ON} in the range 5-48 MW{center_dot}cm{sup -2}. At low biases the reverse leakage current was proportional to the size of the rectifying contact perimeter, while at high biases the current was proportional to the area of this contact. These results suggest that at low reverse biases, the leakage is dominated by the surface component, while at higher biases the bulk component dominates. On-state voltages were 3.5V for the 550V diodes and {ge}15 for the 2kV diodes. Reverse recovery times were <0.2{micro}sec for devices switched from a forward current density of {approx}500A{center_dot}cm{sup -2} to a reverse bias of 100V.

CAO,X.A.; CHO,H.; CHU,S.N.G.; CHUO,C.-C.; CHYI,J.-I.; DANG,G.T.; HAN,JUNG; LEE,C.-M.; PEARTON,S.J.; REN,F.; WILSON,R.G.; ZHANG,A.P.

1999-10-25T23:59:59.000Z

229

primary frequency standards  

Science Conference Proceedings (OSTI)

NIST-F1 Cesium Fountain Atomic Clock The Primary Time and Frequency Standard for the United States. NIST-F1, the nation's ...

2013-02-04T23:59:59.000Z

230

Dynamics of Charged-particle Between the DC Voltage Biased Plane-Parallel Conductors  

E-Print Network (OSTI)

The analytic description to an oscillating charged-particle between the DC voltage biased plane-parallel conductors is presented. Contrary to the traditional belief in which the oscillatory behavior of the charged-particle in a uniform DC field is attributed to the reversal in the sign of the particle's charge polarity as it rebounds between the two electrodes, the analytic description of the phenomenon presented in this work reveals that such requirement is not necessary for the charged-particle oscillation. Since the system involves a spatially oscillating charged-particle, it represents a natural prototype for illuminating electric dipole radiation. By varying the DC bias voltage across the plane-parallel electrodes, the frequency of radiated electromagnetic waves can be adjusted. The device based on charged-particle oscillation is predicted to generate the coherent electromagnetic waves in the microwave to the X-ray regions of the spectrum, which includes the technologically important terahertz, the infra...

Cho, Sung Nae

2011-01-01T23:59:59.000Z

231

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

SciTech Connect

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.

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

1997-04-01T23:59:59.000Z

232

Stabilized radio frequency quadrupole  

DOE Patents (OSTI)

Disclosed is a long-vane stabilized radio frequency resonator for accelerating charged particles and including means defining a radio frequency resonator cavity, a plurality of long vanes mounted in the defining means for dividing the cavity into sections, and means interconnecting opposing ones of the plurality of vanes for stabilizing the resonator. 5 figs.

Lancaster, H.D.; Fugitt, J.A.; Howard, D.R.

1984-12-25T23:59:59.000Z

233

Estimating frequency of change  

Science Conference Proceedings (OSTI)

Many online data sources are updated autonomously and independently. In this article, we make the case for estimating the change frequency of data to improve Web crawlers, Web caches and to help data mining. We first identify various scenarios, where ... Keywords: Change frequency estimation, Poisson process

Junghoo Cho; Hector Garcia-Molina

2003-08-01T23:59:59.000Z

234

Method for sputtering with low frequency alternating current  

DOE Patents (OSTI)

Low frequency alternating current sputtering is provided by connecting a low frequency alternating current source to a high voltage transformer having outer taps and a center tap for stepping up the voltage of the alternating current. The center tap of the transformer is connected to a vacuum vessel containing argon or helium gas. Target electrodes, in close proximity to each other, and containing material with which the substrates will be coated, are connected to the outer taps of the transformer. With an applied potential, the gas will ionize and sputtering from the target electrodes onto the substrate will then result. The target electrodes can be copper or boron, and the substrate can be stainless steel, aluminum, or titanium. Copper coatings produced are used in place of nickel and/or copper striking. 6 figs.

Timberlake, J.R.

1996-04-30T23:59:59.000Z

235

Method for sputtering with low frequency alternating current  

DOE Patents (OSTI)

Low frequency alternating current sputtering is provided by connecting a low frequency alternating current source to a high voltage transformer having outer taps and a center tap for stepping up the voltage of the alternating current. The center tap of the transformer is connected to a vacuum vessel containing argon or helium gas. Target electrodes, in close proximity to each other, and containing material with which the substrates will be coated, are connected to the outer taps of the transformer. With an applied potential, the gas will ionize and sputtering from the target electrodes onto the substrate will then result. The target electrodes can be copper or boron, and the substrate can be stainless steel, aluminum, or titanium. Copper coatings produced are used in place of nickel and/or copper striking.

Timberlake, John R. (Allentown, NJ)

1996-01-01T23:59:59.000Z

236

A method for sputtering with low frequency alternating current  

DOE Patents (OSTI)

Low frequency alternating current sputtering is provided by connecting a low frequency alternating current to a high voltage transformer having outer taps and a center tap for stepping up the voltage of the alternating currentThe center tap of the tmsformer is connected to a vacuum vessel containing argon or helium gas. Target electrodes, in close proximity to each other, and containing material with which the substrates will be coated, are connected to the outer taps of the ftwsformer. With an applied potential, the gas will ionize and sputtering from the target electrodes onto the substrate will then result. The target electrodes can be copper or boron, and the substrate can be stainless steel, aluminum, or titanium. Copper coatings produced are used in place of nickel and/or copper striking.

Timberlake, J.R.

1993-12-31T23:59:59.000Z

237

Microfabricated ion frequency standard  

DOE Patents (OSTI)

A microfabricated ion frequency standard (i.e. an ion clock) is disclosed with a permanently-sealed vacuum package containing a source of ytterbium (Yb) ions and an octupole ion trap. The source of Yb ions is a micro-hotplate which generates Yb atoms which are then ionized by a ultraviolet light-emitting diode or a field-emission electron source. The octupole ion trap, which confines the Yb ions, is formed from suspended electrodes on a number of stacked-up substrates. A microwave source excites a ground-state transition frequency of the Yb ions, with a frequency-doubled vertical-external-cavity laser (VECSEL) then exciting the Yb ions up to an excited state to produce fluorescent light which is used to tune the microwave source to the ground-state transition frequency, with the microwave source providing a precise frequency output for the ion clock.

Schwindt, Peter (Albuquerque, NM); Biedermann, Grant (Albuquerque, NM); Blain, Matthew G. (Albuquerque, NM); Stick, Daniel L. (Albuquerque, NM); Serkland, Darwin K. (Albuquerque, NM); Olsson, III, Roy H. (Albuquerque, NM)

2010-12-28T23:59:59.000Z

238

Planar LTCC transformers for high voltage flyback converters.  

SciTech Connect

This paper discusses the design and use of low-temperature (850 C to 950 C) co-fired ceramic (LTCC) planar magnetic flyback transformers for applications that require conversion of a low voltage to high voltage (> 100V) with significant volumetric constraints. Measured performance and modeling results for multiple designs showed that the LTCC flyback transformer design and construction imposes serious limitations on the achievable coupling and significantly impacts the transformer performance and output voltage. This paper discusses the impact of various design factors that can provide improved performance by increasing transformer coupling and output voltage. The experiments performed on prototype units demonstrated LTCC transformer designs capable of greater than 2 kV output. Finally, the work investigated the effect of the LTCC microstructure on transformer insulation. Although this paper focuses on generating voltages in the kV range, the experimental characterization and discussion presented in this work applies to designs requiring lower voltage.

Schofield, Daryl (NASCENT Technology Inc. , Watertown, SD); Schare, Joshua M.; Glass, Sarah Jill; Roesler, Alexander William; Ewsuk, Kevin Gregory; Slama, George (NASCENT Technology Inc. , Watertown, SD); Abel, Dave (NASCENT Technology Inc. , Watertown, SD)

2007-06-01T23:59:59.000Z

239

Minimum Energy Compensation Strategy and Characteristic Analysis for Dynamic Voltage Restorer  

Science Conference Proceedings (OSTI)

The minimum energy compensation strategy and its characteristic for Dynamic Voltage Restorer (DVR) considering the equipment’s voltage limitation are discussed. The strategy when the injection voltage is under or especially above the voltage limitation ... Keywords: dynamic voltage restorer, minimum energy compensation, compensation strategy, compensation characteristic, voltage limitation

Yingying Liu; Xu Yonghai; Xiao Xiangning; Guo Chunlin

2009-10-01T23:59:59.000Z

240

Research on the SPLL based single phase voltage sag detection technique  

Science Conference Proceedings (OSTI)

The drop of voltage amplitude and the jump of phase angle are two important parameters of the voltage sag. The design of Dynamic Voltage Restorer (DVR) compensation voltage with voltage sag parameters is discussed and a single-phase sag parameter detection ... Keywords: SPLL, detection, single-phase, voltage sag

Xie Yue; Chen Le; Sun Jian; Gong Xu

2008-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "voltage abnormal frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Sequential circuit design for radiation hardened multiple voltage integrated circuits  

DOE Patents (OSTI)

The present invention includes a radiation hardened sequential circuit, such as a bistable circuit, flip-flop or other suitable design that presents substantial immunity to ionizing radiation while simultaneously maintaining a low operating voltage. In one embodiment, the circuit includes a plurality of logic elements that operate on relatively low voltage, and a master and slave latches each having storage elements that operate on a relatively high voltage.

Clark, Lawrence T. (Phoenix, AZ); McIver, III, John K. (Albuquerque, NM)

2009-11-24T23:59:59.000Z

242

Waveform Characteristics of Voltage Sags: Definition and Algorithm Development  

Science Conference Proceedings (OSTI)

Voltage disturbances lasting more than one cycle are normally characterized in terms of voltage magnitude and event duration. These parameters provide an easily understood means of characterizing these types of voltage disturbances. However, magnitude and duration are not the only characteristics that affect loads. Many types of loads, such as contactors, control systems, and ac/dc drives, are also affected by other factors, such as the waveshape, the point in the waveform at which the disturbance begins...

1999-08-05T23:59:59.000Z

243

Triple voltage dc-to-dc converter and method  

DOE Patents (OSTI)

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.

Su, Gui-Jia (Knoxville, TN)

2008-08-05T23:59:59.000Z

244

High Voltage Electric Discharge Consolidation of Tantalum Powders  

Science Conference Proceedings (OSTI)

Abstract Scope, The high voltage electric discharge consolidation (HVEDC) is a promising method of the volumetric-porous body manufacturing, which can be ...

245

The Current-voltage Characteristics of Grain Boundaries in Ionic ...  

Science Conference Proceedings (OSTI)

Presentation Title, The Current-voltage Characteristics of Grain Boundaries in Ionic ... A High-temperature Mössbauer Study of Iron-doped Ruddlesden-popper  ...

246

(SPS) and High Voltage Electric Discharge Consolidation (HVEDC  

Science Conference Proceedings (OSTI)

Presentation Title, Inter-Particle Contact Phenomena in Spark-Plasma Sintering ( SPS) and High Voltage Electric Discharge Consolidation (HVEDC). Author(s) ...

247

Spark-plasma Sintering vs. High Voltage Electric Discharge ...  

Science Conference Proceedings (OSTI)

High voltage electric discharge consolidation (HVEDC) includes high axial pressure and discharge of the electrical energy stored in capacitors, thus enabling a ...

248

Voltage Controlled Creep of a Nanoporous Gold/Electrolyte Hybrid ...  

Science Conference Proceedings (OSTI)

And the creep rate can also be controlled by the voltage (electrochemical ... CNT Reinforced Copper Composite for High Contact Pressure Electrodes by ...

249

(SPS) and High Voltage Electric Discharge Consolidation (HVEDC)  

Science Conference Proceedings (OSTI)

Presentation Title, Local Heat Balance in Spark-plasma Sintering (SPS) and High Voltage Electric Discharge Consolidation (HVEDC). Author(s), Eugene ...

250

Road to AC Voltage Standard Leads to Important Junction  

Science Conference Proceedings (OSTI)

Road to AC Voltage Standard Leads to Important Junction. ... Grumman in the mid-1990s.*** A number of innovations since then have led to the first ...

2013-08-13T23:59:59.000Z

251

Chronic Benzodiazepine Administration Potentiates High Voltage-Activated Calcium Currents  

E-Print Network (OSTI)

.aspetjournals.orgDownloadedfrom #12;other drugs of abuse has been reported to enhance high voltage-activated calcium channels (HVAs

Brand, Paul H.

252

fault diagnosis of a high voltage transmission line using waveform ...  

E-Print Network (OSTI)

Oct 4, 2013 ... FAULT DIAGNOSIS OF A HIGH VOLTAGE TRANSMISSION LINE USING ... Fault types such as single line to ground, line to line, double line to ...

253

Multi-winding Homopolar Electric Machine Offers Variable Voltage ...  

Wind Energy Industrial Technologies Multi-winding Homopolar Electric Machine Offers Variable Voltage at Low Rotational Speed Oak Ridge National Laboratory. Contact ...

254

Energy-Big voltage, little package... | ornl.gov  

NLE Websites -- All DOE Office Websites (Extended Search)

News DOE Pulse Media Contacts Media Mentions RSS Feeds News Home | ORNL | News | Story Tips SHARE Energy-Big voltage, little package Oak Ridge National Laboratory's new Stinger...

255

Specifying a Low-Voltage Dynamic Sag Corrector  

Science Conference Proceedings (OSTI)

Voltage sags are the most frequent and costly of power quality problems for industrial customers. A number of non-battery-based technologies have emerged in the market to mitigate the effects of voltage sags on industrial processes. Among these, the low-voltage dynamic sag corrector (DySC) can provide ride-through during sags to 50 percent of nominal voltage for up to 12 cycles with no energy storage; for longer ride-through or deeper sags, energy storage capacitors are available as an option. This repor...

2000-11-07T23:59:59.000Z

256

A Step Towards Energy-Efficient Voltage Control of Magnetic ...  

Science Conference Proceedings (OSTI)

... By combining these two types of materials, it is possible to create low ... by electric fields (applied voltage) instead of less energy-efficient magnetic ...

2013-07-30T23:59:59.000Z

257

Medium Voltage Cable Aging Management Guide, Revision 1  

Science Conference Proceedings (OSTI)

Medium-voltage cables (5- to 35-kV rated cables) have provided reasonable service in nuclear power plants. However, there is a concern that cables that have experienced long periods of wet service might degrade and fail in service. Because most plants have had few problems with medium-voltage cable, little on-staff experience with medium-voltage cables exists at most sites. This report has been prepared to provide information that will be of practical use when questions concerning medium-voltage cable lo...

2010-11-29T23:59:59.000Z

258

Operating standby redundant controller to improve voltage source inverter reliability .  

E-Print Network (OSTI)

??This thesis presents a control architecture that achieves operating standby redundancy for a voltage source inverter controller. The system was designed to increase reliability by… (more)

Blevins, Stephen T.

2007-01-01T23:59:59.000Z

259

California ISO Real-Time Voltage Security Assessment (VSA) Project...  

NLE Websites -- All DOE Office Websites (Extended Search)

Arnold Schwarzenegger Governor REAL-TIME GRID RELIABILITY MANAGEMENT California ISO Real-Time Voltage Security Assessment (VSA) Project: Summary of Survey Results on Methodologies...

260

Patents and Perspective on Surge Protection for Low-Voltage ...  

Science Conference Proceedings (OSTI)

... In a high-voitage inverter the impedance is a resistor functioning to dampen voltage o\\ershoots and to im- plement a relay or solid state second ...

2013-05-17T23:59:59.000Z

Note: This page contains sample records for the topic "voltage abnormal frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Surge Protection in Low-Voltage AC Power Circuits  

Science Conference Proceedings (OSTI)

Surge Protection in Low-Voltage AC Power Circuits: An 8-part Anthology ... converting old and yellowing papers into 21st Century electronic files, and ...

2013-05-20T23:59:59.000Z

262

Definition: Frequency-Domain Electromagnetics Survey | Open Energy  

Open Energy Info (EERE)

Frequency-Domain Electromagnetics Survey Frequency-Domain Electromagnetics Survey Jump to: navigation, search Dictionary.png Frequency-Domain Electromagnetics Survey Frequency-domain electromagnetic techniques are continuous wave field methods which enable the mapping of the electrical conductivity of the subsurface through electromagnetic induction.[1] View on Wikipedia Wikipedia Definition Electromagnetic induction is the production of a potential difference (voltage) across a conductor when it is exposed to a varying magnetic field. Michael Faraday is generally credited with the discovery of induction in 1831 though it may have been anticipated by the work of Francesco Zantedeschi in 1829. Around 1830 to 1832, Joseph Henry made a similar discovery, but did not publish his findings until later. Faraday's

263

Voltage Unbalance: Power Quality Issues, Related Standards and Mitigation Techniques: Effect of Unbalanced Voltage on End Use Equipm ent Performance  

Science Conference Proceedings (OSTI)

Unbalanced voltages can result in adverse effects on equipment and the electric distribution system. Under unbalanced conditions the distribution system will incur more losses and heating effects, and be less stable. The effect of voltage unbalance can also be detrimental to equipment such as induction motors, power electronic converters, and adjustable speed drives (ASDs). The purpose of this study is to investigate the causes and effects of voltage unbalance as well as the related standards and mitigat...

2000-06-21T23:59:59.000Z

264

Graphene Frequency Multipliers  

E-Print Network (OSTI)

In this letter, the ambipolar transport properties of graphene flakes have been used to fabricate full-wave signal rectifiers and frequency-doubling devices. By correctly biasing an ambipolar graphene field-effect transistor ...

Wang, Han

265

Power frequency communication on long feeders and high levels of harmonic distortion  

SciTech Connect

TWACS is a unique Power Frequency Communication (PFC) technology. The power voltage is modulated at the substation bus for outbound communication and inbound communication from a remote transponder is accomplished by drawing precisely controlled current pulses which are detectable at the distribution substation. The propagation characteristics of the TWACS signal and the frequency characteristics of the signal detector make it possible to communicate over very long distribution feeders and provide a high degree of immunity against harmonic distortions of the power system voltage and current.

Mak, S.T.; Maginnis, R.L. [Distribution Control Systems, Inc., Hazelwood, MO (United States)

1995-10-01T23:59:59.000Z

266

Local Dynamic Reactive Power for Correction of System Voltage Problems  

SciTech Connect

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

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

2008-12-01T23:59:59.000Z

267

Transmission gates combined with level-restoring CMOS gates reduce glitches in low-power low-frequency multipliers  

Science Conference Proceedings (OSTI)

Various 16-bit multiplier architectures are compared in terms of dissipated energy, propagation delay, energy-delay product (EDP), and area occupation, in view of low-power low-voltage signal processing for low-frequency applications. A novel practical ... Keywords: arithmetic, glitch, low frequency, low power, multiplier, switching activity, transmission gate

Flavio Carbognani; Felix Buergin; Norbert Felber; Hubert Kaeslin; Wolfgang Fichtner

2008-07-01T23:59:59.000Z

268

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

Science Conference Proceedings (OSTI)

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

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

2008-01-01T23:59:59.000Z

269

UPGRADING THE CEBAF INJECTOR WITH A NEW BOOSTER, HIGHER VOLTAGE GUN, AND HIGHER FINAL ENERGY  

Science Conference Proceedings (OSTI)

The Continuous Electron Beam Accelerator Facility (CEBAF) accelerator at Jefferson Lab will be upgraded from 6 GeV to 12 GeV in the next few years. To meet the requirement of the new machine and to take the opportunity to improve the beam quality, the CEBAF injector will be upgraded with a higher voltage gun, a new booster, and a new accelerating RF module. The CEBAF injector creates and accelerates three beams at different currents simultaneously. The beams are interleaved, each at one third of the RF frequency, traveling through the same beam line. The higher voltage gun will lower the space charge effects. The new booster with optimized beam dynamics will complete the bunching process and provide initial acceleration matched to the new gun voltage. Using our latest SRF design, the new booster has significantly lower x/y coupling effects that should improve our beam setup and operation for the highly sensitive parity experiments scheduled for the CEBAF's future. Finally, the new accelerating RF module will roughly double the injector final energy to match the rest of the 12 GeV accelerator. In this paper we will provide more detail about this upgrade.

Reza Kazimi, Arne Freyberger, Alicia Hofler, Andrew Hutton, Fay Hannon

2012-07-01T23:59:59.000Z

270

Qualification High Voltage Testing of Short Triax HTS Cables in the Laboratory  

Science Conference Proceedings (OSTI)

In order to qualify the electrical insulation design of future HTS cables installed in the electric grid, a number of high voltage qualification tests are generally performed in the laboratory on either single-phase model cables and/or actual three-phase cable samples. Prior to installation of the 200-m Triax HTS cable at the American Electric Power Bixby substation near Columbus, Ohio, in September, 2006, such tests were conducted on both single-phase model cables made at ORNL and tri-axial cable sections cut off from cable made on a production run. The three-phase tri-axial design provides some specific testing challenges since the ground shield and three phases are concentric about a central former with each phase separated by dielectric tape insulation immersed in liquid nitrogen. The samples were successfully tested and qualified for partial discharge inception, AC withstand, and lightning impulse where voltage is applied to one phase with the other phases grounded. In addition one of the phase pairs was tested for dc withstand as a ldquoworst caserdquo scenario to simulate the effect of VLF (Very Low Frequency) tests on the actual cable installed at the Bixby site. The model and prototype cables will be described and the high voltage test results summarized.

James, David Randy [ORNL; Sauers, Isidor [ORNL; Ellis, Alvin R [ORNL; Tuncer, Enis [ORNL; Gouge, Michael J [ORNL; Demko, Jonathan A [ORNL; Duckworth, Robert C [ORNL; Rey, Christopher M [ORNL

2009-01-01T23:59:59.000Z

271

Robust Design of Basic Low Voltage CMOS Transconductors  

Science Conference Proceedings (OSTI)

Two new low voltage transconductors are introduced and the statistical design of these transconductors are presented. The circuits operate in the saturation region with fully balanced input signals. Initial circuit simulation results are given. Response surface ... Keywords: design of experiments, low voltage, response surface methodology, roboust design, yield enhancement

Tuna B. Tarim; H. Hakan Kuntman; Mohammed Ismail

1999-09-01T23:59:59.000Z

272

Motor voltage asymmetry influence to the efficient energy usage  

Science Conference Proceedings (OSTI)

Analysis of the effect of unbalanced voltages on the three-phase induction motor is presented in the paper. Since the unbalanced voltage of 2%, 3.5% and 5% increase in losses could reach, in the same order, the amount of 8%, 25% and 50% of nominal power ... Keywords: asymetry, energy efficiency, induction motor, power losses, standard

Miloje Kostic; Aleksandar Nikolic

2010-07-01T23:59:59.000Z

273

Analysis of Voltage Notching Concerns at a Petroleum Pumping Station  

Science Conference Proceedings (OSTI)

This report presents the results of a voltage notching investigation at a petroleum pumping station. The analysis in this paper focuses on a particular example system where the voltage notching caused significant oscillations at the distribution system level, resulting in equipment problems at another customer supplied from the same system.

2003-12-31T23:59:59.000Z

274

Compile-time dynamic voltage scaling settings: opportunities and limits  

Science Conference Proceedings (OSTI)

With power-related concerns becoming dominant aspects of hardware and software design, significant research effort has been devoted towards system power minimization. Among run-time power-management techniques, dynamic voltage scaling (DVS) has emerged ... Keywords: analytical model, compiler, dynamic voltage scaling, low power, mixed-integer linear programming

Fen Xie; Margaret Martonosi; Sharad Malik

2003-06-01T23:59:59.000Z

275

Real-time static voltage scaling on multiprocessors  

Science Conference Proceedings (OSTI)

We propose a real-time static voltage scaling (RT-SVS) technique called T-L plane transforming, which is an extension of LLREF, an optimal real-time scheduling algorithm for multiprocessor systems. We present two RT-SVS algorithms for different types ... Keywords: energy consumption, multiprocessor systems, real-time scheduling, real-time voltage scaling

Kenji Funaoka; Shinpei Kato; Nobuyuki Yamasaki

2007-11-01T23:59:59.000Z

276

Proceedings: EPRI/NERC Forum on Voltage Stability  

Science Conference Proceedings (OSTI)

As power systems are operated at increased stress, utilities are becoming more concerned about voltage collapse and consequent severe disruptions. This meeting, cosponsored by EPRI and NERC, provided a forum for a group of international experts to exchange information on voltage stability, including its physical understanding, operational practices, and application of available tools.

1993-06-01T23:59:59.000Z

277

Wind Farm Grid Voltage Stability Researching Based on Cascade STATCOM  

Science Conference Proceedings (OSTI)

Though most wind turbine use induction generator, when wind induction generator with power generation, it will produce a series of power quality problems such as voltage fluctuations. This paper discusses the mathematical model of the wind induction ... Keywords: Wind induction generator, Cascade STATCOM, Wind farm, Voltage stability

Li Shengqing, Xu Wenxiang, Li Weizhou, Zeng Huanyue

2013-01-01T23:59:59.000Z

278

Definition: Automated Voltage And Var Control | Open Energy Information  

Open Energy Info (EERE)

Voltage And Var Control Voltage And Var Control Jump to: navigation, search Dictionary.png Automated Voltage And Var Control Automated voltage and VAR control requires coordinated operation of reactive power resources such as capacitor banks, voltage regulators, transformer load-tap changers, and distributed generation (DG) with sensors, controls, and communications systems. These devices could operate autonomously in response to local events or in response to signals from a central control system.[1] View on Wikipedia Wikipedia Definition Also Known As Volt-VAR Control (VVC) Related Terms smart grid, Reactive Power References ↑ SmartGrid.gov 'Description of Functions' An i LikeLike UnlikeLike You like this.Sign Up to see what your friends like. nline Glossary Definition Retrieved from

279

Living and Working Safely Around High-Voltage Power Lines.  

Science Conference Proceedings (OSTI)

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

United States. Bonneville Power Administration.

2001-06-01T23:59:59.000Z

280

Reactive Power Management to Address Short-Term Voltage Stability Using Optimal Reactive Power Allocation Method  

Science Conference Proceedings (OSTI)

Voltage stability has attracted attention recently because power systems are increasingly operated under heavy loads and subjected to high levels of dynamic fast acting loads. Voltage instability under these conditions can be manifested as depressed voltage profiles, delayed voltage recovery at load buses following a major disturbance, and even fast voltage collapse. Single-phase, low-inertia induction motors can have adverse effect on voltage stability as they decelerate in the event of voltage ...

2012-11-28T23:59:59.000Z

Note: This page contains sample records for the topic "voltage abnormal frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Improving the low voltage ride through of doubly fed induction generator during intermittent voltage source converter faults  

E-Print Network (OSTI)

on the low voltage ride through (LVRT) capability of the doubly fed induction generator (DFIG) is also) controller to mitigate the effects of these faults is proposed. The DFIG compliance with numerous and compared. Simulation results indicate that these types of faults have a severe impact on the DFIG voltage

Pota, Himanshu Roy

282

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

Science Conference Proceedings (OSTI)

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

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

2011-12-15T23:59:59.000Z

283

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

DOE Patents (OSTI)

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).

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

1993-01-19T23:59:59.000Z

284

A Survey on the Principle and Control of Dynamic Voltage Restorer  

Science Conference Proceedings (OSTI)

With the development of information and automation techniques, dynamic voltage problems are once again in the spotlight. Dynamic voltage restorer (DVR) is a modern and important custom power device used for mitigating voltage sags in power distribution ... Keywords: voltage sag, dynamic voltage restorer (DVR), control strategy, power quality, optimized compensation, energy storage

Shuhong Kong; Zhongdong Yin; Renzhong Shan; Weidong Shang

2009-10-01T23:59:59.000Z

285

Why inverse document frequency?  

Science Conference Proceedings (OSTI)

Inverse Document Frequency (IDF) is a popular measure of a word's importance. The IDF invariably appears in a host of heuristic measures used in information retrieval. However, so far the IDF has itself been a heuristic. In this paper, we show IDF to ...

Kishore Papineni

2001-06-01T23:59:59.000Z

286

A New Method of Identifying the Low Frequency Oscillations of Power Systems  

Science Conference Proceedings (OSTI)

To solve the order choice problem in Prony algorithm, active power or voltage signals are usually used by Prony algorithms based on singular values decomposition-total least square (SVD-TLS). Because of the difference in choosing the standard parameters ... Keywords: power systems, low frequency oscillations, improved Prony algorithm, SVD-TLS, DVR, SNR

Yishu Zhao; Yang Gao; Zhijian Hu; Yongjun Yang; Jie Zhan; Yan Zhang

2009-10-01T23:59:59.000Z

287

Design of a fast-settling OTA for high frequency switched-capacitor applications  

E-Print Network (OSTI)

The ever-growing technology has enabled switched-capacitor (SC) circuits to operate at the MHz frequency range. The equally increasing demand for high speed signal processing using SC technique dictates the need of high performance operational amplifiers (opamps). Low voltage and low poer operation, one of the main industrial trends, however, puts significant challenges to analog circuit designers. In current digital-dominant technology, CMOS devices have become more suitable for digital circuit design; they require lower operation voltage with threshold voltages decreasing relatively sluggish. Designers should still be able to design circuits with the same or better performance then circuits designed for larger power supplies. As more and more building blocks and systems are getting integrated into smaller area, they still must be designed to achieve the needs of portable, lighter and reliable product. In this thesis, characteristics of low voltage and low power SC circuits for high frequency applications are investigated. Several candidates of opamp architecture are compared in light of limitations aforementioned and design issues of selected topology are to be further examined. The proposed solution is designed at transistor level in Hewlett Packard 0.5 []m digital CMOS technology. As a test bench, a SC biquad band pass filter with sampling frequency of up to 120 MHz and center frequency of 20 MHz is designed and fabricated through MOSIS. Test results of fabricated IC's are presented and the validity of this research is accordingly justified.

Park, Jinki

2002-01-01T23:59:59.000Z

288

Fault Detection and Isolation in Low-Voltage DC Distribution ...  

A University of Colorado research team led by Jae-Do Park has developed a fault detection and isolation scheme for a low-voltage DC-bus microgrid system, ...

289

NIST Online Museum of Quantum Voltage Standards, 1970s  

Science Conference Proceedings (OSTI)

... Metrologists wondered if they could connect several junctions in series to make a larger voltage, just as a 12-volt car battery is made up of six 2-volt ...

2011-03-30T23:59:59.000Z

290

Fusing strategies for the dual-voltage fault  

E-Print Network (OSTI)

This thesis focuses on the 42V - 14V fault in a dual voltage system and discusses the possibility of effective fusing. A simple model for the system had been created from technical documentation. Based on the model and the ...

Shrivastava, Rupam, 1981-

2005-01-01T23:59:59.000Z

291

Functionalized High Voltage Spinel Composite for High Power ...  

Science Conference Proceedings (OSTI)

Recently, spinel LiNi0.5Mn1.5O4 with high working voltage and long cycle life makes it become the one of most promising cathode for high power delivery.

292

ESS 2012 Peer Review - Low Cost, Manufacturable High Voltage...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Storage for Power Flow Management and Voltage Control on an 11kV UK Distribution Network", 20th International Conference on Electricity Distribution, June 2009. S1 S2 C1 C2...

293

Multilevel cascade voltage source inverter with seperate DC sources  

SciTech Connect

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.

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

1997-01-01T23:59:59.000Z

294

Multilevel cascade voltage source inverter with seperate DC sources  

DOE Patents (OSTI)

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.

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

2002-01-01T23:59:59.000Z

295

Design & Fabrication of a High-Voltage Photovoltaic Cell  

DOE Green Energy (OSTI)

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.

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

2012-09-05T23:59:59.000Z

296

Robust Design of Basic Low Voltage CMOS Transconductors  

Science Conference Proceedings (OSTI)

Two new low voltage transconductors are introduced and the statistical design of these transconductors are presented. The circuits operate in the saturation region with fully balanced input signals. Initial circuit simulation results are given. Response surface ...

Tuna B. Tarim; H. Hakan Kuntman; Mohammed Ismail

1999-09-01T23:59:59.000Z

297

High-voltage air-core pulse transformers  

SciTech Connect

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)

Rohwein, G. J.

1981-01-01T23:59:59.000Z

298

High power impulse magnetron sputtering: Current-voltage-time ...  

pauses between pulses !typically 20 ms". The nominal volt-age of the pulser was adjustable up to 1000 V. The arc threshold was set to 120 A. If the current exceeded this

299

Planar LTCC transformers for high voltage flyback converters: Part II.  

Science Conference Proceedings (OSTI)

This paper is a continuation of the work presented in SAND2007-2591 'Planar LTCC Transformers for High Voltage Flyback Converters'. The designs in that SAND report were all based on a ferrite tape/dielectric paste system originally developed by NASCENTechnoloy, Inc, who collaborated in the design and manufacturing of the planar LTCC flyback converters. The output/volume requirements were targeted to DoD application for hard target/mini fuzing at around 1500 V for reasonable primary peak currents. High voltages could be obtained but with considerable higher current. Work had begun on higher voltage systems and is where this report begins. Limits in material properties and processing capabilities show that the state-of-the-art has limited our practical output voltage from such a small part volume. In other words, the technology is currently limited within the allowable funding and interest.

Schofield, Daryl (NASCENTechnology, Inc., Watertown, SD); Schare, Joshua M., Ph.D.; Slama, George (NASCENTechnology, Inc., Watertown, SD); Abel, David (NASCENTechnology, Inc., Watertown, SD)

2009-02-01T23:59:59.000Z

300

Multilevel cascade voltage source inverter with separate DC sources  

DOE Patents (OSTI)

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.

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

1997-06-24T23:59:59.000Z

Note: This page contains sample records for the topic "voltage abnormal frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Time varying voltage combustion control and diagnostics sensor  

DOE Patents (OSTI)

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.

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

302

Light Flicker in Compact Fluorescent Lamps Caused by Voltage Fluctuations  

Science Conference Proceedings (OSTI)

This power quality (PQ) case study presents tests performed at the EPRI Power Electronics Applications Center (PEAC) Power Quality Test Facility to characterize the light output of an incandescent lamp and compact fluorescent lamps during voltage fluctuations.

2003-12-31T23:59:59.000Z

303

A Novel Dynamic Voltage Restorer with Outage Handling Capability Using Fuzzy Logic Controler  

Science Conference Proceedings (OSTI)

This paper presents a novel dynamic voltage restorer (DVR) capable of handling deep sags including outage on a low voltage distribution system. The DVR recovers sags up to 10% of nominal voltage; otherwise, it will operate as an uninterruptible power ...

M. Ashari; T. Hiyama; M. Pujiantara; H. Suryoatmojo; M. Hery Purnomo

2007-09-01T23:59:59.000Z

304

Elevated Neutral to Earth and Contact Voltages in Distribution Systems  

Science Conference Proceedings (OSTI)

Perceptible voltage potentials at publicly and privately accessible human and animal contact locations pose concerns for utilities, regulators, and the public. Each year since 2004, EPRI research in this area has considered the most important concerns associated with these perceptible voltages by promoting consistent and repeatable assessment methodologies, sponsoring workshops, and creating a repository of case studies and general information. These and other project efforts are geared toward expediting...

2008-12-18T23:59:59.000Z

305

INTENSITY OF BETATRON RADIATION AS FUNCTION OF INJECTION VOLTAGE  

SciTech Connect

The intensity of betatron radiation emission as a function of injection voltage was studied using a 25-Mev betatron with a 350-kw external electron injector. The injection voltage was measured every 20 to 30 kw from 50 to 250 kw. The results showed that up to 250 kw, emission intensity increases according to theory. It is suggested that an increase in injection intensity up to 1000 kw and over should result in a considerable rise in emission intensity. (R.V.J.)

Moskalev, V.A.; Okulov, B.V.

1962-09-01T23:59:59.000Z

306

Chloromethyl chlorosulfate as a voltage delay inhibitor in lithium cells  

DOE Patents (OSTI)

Chloromethyl chlorosulfate (CMCS) is used as a passive film growth inhibitor in electrochemical cells to minimize voltage delay and low-voltage discharge. Film growth on lithium anodes is significantly diminished when CMCS is added to SOCl{sub 2} and SO{sub 2}Cl{sub 2} electrolytes of lithium batteries. The CMCS also has the effect of extending the shelf-life of Li/SOCl{sub 2} and Li/SO{sub 2}Cl{sub 2} batteries.

Delnick, F.M.

1991-04-05T23:59:59.000Z

307

Cable Aging Management Training Course for Low-Voltage Cables  

Science Conference Proceedings (OSTI)

The "EPRI PSE Cable Aging Training Course for Low-Voltage Cables" provides a basis for understanding of the aging of the insulation and jackets of electrical cables used in low-voltage systems. Practical techniques for determining which cables are prone to premature aging and for evaluating their condition are described. The course contains 11 modules. The first 9 modules describe the body of the cable aging management process. The last two modules, "Cable Failure Assessment" and "Performing a Walkdown o...

2003-11-24T23:59:59.000Z

308

Optical control system for high-voltage terminals  

DOE Patents (OSTI)

An optical control system for the control of devices in the terminal of an electrostatic accelerator includes a laser that is modulated by a series of preselected codes produced by an encoder. A photodiode receiver is placed in the laser beam at the high-voltage terminal of an electrostatic accelerator. A decoder connected to the photodiode decodes the signals to provide control impulses for a plurality of devices at the high voltage of the terminal.

Bicek, John J. (Tinley Park, IL)

1978-01-01T23:59:59.000Z

309

Chloromethyl chlorosulfate as a voltage delay inhibitor in lithium cells  

DOE Patents (OSTI)

Chloromethyl chlorosulfate (CMCS) is used as a passive film growth inhibitor in electrochemical cells to minimize voltage delay and low-voltage discharge. Film growth on lithium anodes is significantly diminished when CMCS is added to SOCl.sub.2 and SO.sub.2 Cl.sub.2 electrolytes of lithium batteries. The CMCS also has the effect of extending the shelf-life of Li/SOCl.sub.2 and Li/SO.sub.2 Cl.sub.2 batteries.

Delnick, Frank M. (Albuquerque, NM)

1993-01-01T23:59:59.000Z

310

Chloromethyl chlorosulfate as a voltage delay inhibitor in lithium cells  

DOE Patents (OSTI)

Chloromethyl chlorosulfate (CMCS) is used as a passive film growth inhibitor in electrochemical cells to minimize voltage delay and low-voltage discharge. Film growth on lithium anodes is significantly diminished when CMCS is added to SOCl[sub 2] and SO[sub 2]Cl[sub 2] electrolytes of lithium batteries. The CMCS also has the effect of extending the shelf-life of Li/SOCl[sub 2] and Li/SO[sub 2]Cl[sub 2] batteries.

Delnick, F.M.

1993-04-13T23:59:59.000Z

311

Measuring Helical FCG Voltage with an Electric Field Antenna  

SciTech Connect

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

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

2011-08-01T23:59:59.000Z

312

High voltage series connected tandem junction solar battery  

DOE Patents (OSTI)

A high voltage series connected tandem junction solar battery which comprises a plurality of strips of tandem junction solar cells of hydrogenated amorphous silicon having one optical path and electrically interconnected by a tunnel junction. The layers of hydrogenated amorphous silicon, arranged in a tandem configuration, can have the same bandgap or differing bandgaps. The tandem junction strip solar cells are series connected to produce a solar battery of any desired voltage.

Hanak, Joseph J. (Lawrenceville, NJ)

1982-01-01T23:59:59.000Z

313

Discrete pulse modulation strategies for high-frequency inverter systems  

SciTech Connect

High-performance high-frequency inverter systems for UPS applications represent a demanding application that cannot be easily realized using conventional hard-switched PWM inverter topologies. Adoption of typical soft-switched inverters such as the resonant dc link inverter require the use of discrete pulse modulation strategies. New controller structures are necessary to cope with stringent voltage regulation and distortion constraints in the presence of unbalanced and nonlinear loads. This paper presents a controller that utilizes load current feed-forward strategy with a cost function current regulator to achieve excellent transient performance characteristics. Voltage regulation is ensured using a synchronous frame regulator. Detailed simulation and experimental results verifying the concepts are presented. Although this paper focuses on soft-switching inverters, the control concepts can be applied to conventional hard-switching inverters as well.

Venkataramanan, G. (Montana State Univ., Bozeman, MT (United States). Dept. of Electrical Engineering); Divan, D.M. (Univ. of Wisconsin, Madison, WI (United States). Dept. of Electrical and Computer Engineering); Jahns, T.M. (General Electric Co., Schenectady, NY (United States))

1993-07-01T23:59:59.000Z

314

Design and Implementation of Switching Voltage Integrated Circuits Based on Sliding Mode Control  

E-Print Network (OSTI)

The need for high performance circuits in systems with low-voltage and low-power requirements has exponentially increased during the few last years due to the sophistication and miniaturization of electronic components. Most of these circuits are required to have a very good efficiency behavior in order to extend the battery life of the device. This dissertation addresses two important topics concerning very high efficiency circuits with very high performance specifications. The first topic is the design and implementation of class D audio power amplifiers, keeping their inherent high efficiency characteristic while improving their linearity performance, reducing their quiescent power consumption, and minimizing the silicon area. The second topic is the design and implementation of switching voltage regulators and their controllers, to provide a low-cost, compact, high efficient and reliable power conversion for integrated circuits. The first part of this dissertation includes a short, although deep, analysis on class D amplifiers, their history, principles of operation, architectures, performance metrics, practical design considerations, and their present and future market distribution. Moreover, the harmonic distortion of open-loop class D amplifiers based on pulse-width modulation (PWM) is analyzed by applying the duty cycle variation technique for the most popular carrier waveforms giving an easy and practical analytic method to evaluate the class D amplifier distortion and determine its specifications for a given linearity requirement. Additionally, three class D amplifiers, with an architecture based on sliding mode control, are proposed, designed, fabricated and tested. The amplifiers make use of a hysteretic controller to avoid the need of complex overhead circuitry typically needed in other architectures to compensate non-idealities of practical implementations. The design of the amplifiers based on this technique is compact, small, reliable, and provides a performance comparable to the state-of-the-art class D amplifiers, but consumes only one tenth of quiescent power. This characteristic gives to the proposed amplifiers an advantage for applications with minimal power consumption and very high performance requirements. The second part of this dissertation presents the design, implementation, and testing of switching voltage regulators. It starts with a description and brief analysis on the power converters architectures. It outlines the advantages and drawbacks of the main topologies, discusses practical design considerations, and compares their current and future market distribution. Then, two different buck converters are proposed to overcome the most critical issue in switching voltage regulators: to provide a stable voltage supply for electronic devices, with good regulation voltage, high efficiency performance, and, most important, a minimum number of components. The first buck converter, which has been designed, fabricated and tested, is an integrated dual-output voltage regulator based on sliding mode control that provides a power efficiency comparable to the conventional solutions, but potentially saves silicon area and input filter components. The design is based on the idea of stacking traditional buck converters to provide multiple output voltages with the minimum number of switches. Finally, a fully integrated buck converter based on sliding mode control is proposed. The architecture integrates the external passive components to deliver a complete monolithic solution with minimal silicon area. The buck converter employs a poly-phase structure to minimize the output current ripple and a hysteretic controller to avoid the generation of an additional high frequency carrier waveform needed in conventional solutions. The simulated results are comparable to the state-of-the-art works even with

Rojas Gonzalez, Miguel Angel

2009-08-01T23:59:59.000Z

315

Low-voltage, low-power circuits for data communication systems  

E-Print Network (OSTI)

There are growing industrial demands for low-voltage supply and low-power consumption circuits and systems. This is especially true for very high integration level and very large scale integrated (VLSI) mixed-signal chips and system-on-a-chip. It is mainly due to the limited power dissipation within a small area and the costs related to the packaging and thermal management. In this research work, two low-voltage, low-power integrated circuits used for data communication systems are introduced. The first one is a high performance continuous-time linear phase filter with automatic frequency tuning. The filter can be used in hard disk driver systems and wired communication systems such as 1000Base-T transceivers. A pseudo-differential operational transconductance amplifier (OTA) based on transistors operating in triode region is used to achieve a large linear signal swing with low-voltage supplies. A common-mode (CM) control circuit that combines common-mode feedback (CMFB), common-mode feedforward (CMFF), and adaptive-bias has been proposed. With a 2.3V single supply, the filter?s total harmonic distortion is less than ?44dB for a 2VPP differential input, which is due to the well controlled CM behavior. The ratio of the root mean square value of the ac signal to the power supply voltage is around 31%, which is much better than previous realizations. The second integrated circuit includes two LVDS drivers used for high-speed point-to-point links. By removing the stacked switches used in the conventional structures, both LVDS drivers can operate with ultra low-voltage supplies. Although the Double Current Sources (DCS) LVDS driver draws twice minimum static current as required by the signal swing, it is quite simple and achieves very high speed operation. The Switchable Current Sources (SCS) LVDS driver, by dynamically switching the current sources, draws minimum static current and reduces the power consumption by 60% compared to the previously reported LVDS drivers. Both LVDS drivers are compliant to the standards and operate at data rates up to gigabits-per-second.

Chen, Mingdeng

2003-12-01T23:59:59.000Z

316

Centralized wind power plant voltage control with optimal power flow algorithm.  

E-Print Network (OSTI)

??This thesis presents a method of controlling the reactive power injected into a medium-voltage collection system by multiple wind turbine generators such that the voltage… (more)

Kline, Jared Andrew

2011-01-01T23:59:59.000Z

317

Voltage stability limits for weak power systems with high wind penetration.  

E-Print Network (OSTI)

??Analysis of power system voltage stability has practical value in increasing wind penetration levels. As wind penetration levels increase in power systems, voltage stability challenges… (more)

Tamimi, Ala

2011-01-01T23:59:59.000Z

318

Improving the low voltage ride through of doubly fed induction generator during intermittent voltage source converter faults  

Science Conference Proceedings (OSTI)

The impact of different voltage source converter (VSC) faults on the low voltage ride through (LVRT) capability of the doubly fed induction generator (DFIG) is also investigated. Faults such as fire-through of the VSC switches and short circuit across the DC-link capacitor are considered in this paper. The impact of internal VSC faults when they occur within the grid side converter (GSC)

2013-01-01T23:59:59.000Z

319

VERY LOW FREQUENCY BREAKDOWN PROPERTIES OF ELECTRICAL INSULATION MATERIALS AT CRYOGENIC TEMPERATURES  

SciTech Connect

For long cables or equipment with large capacitance it is not always possible to conduct high voltage withstand at tests at 60 Hz due to limitations in charging currents of the power supply. Very low frequency (typically at a frequency of 0.1 Hz) has been used for conventional cables as a way of getting around the charging current limitation. For superconducting grid applications the same issues apply. However there is very little data at cryogenic temperatures on how materials perform at low frequency compared to 60 Hz and whether higher voltages should be applied when performing a high voltage acceptability test. Various materials including G10 (fiberglass reinforced plastic or FRP), Cryoflex (a tape insulation used in some high temperature superconducting cables), kapton (commonly used polyimide), polycarbonate, and polyetherimide, and in liquid nitrogen alone have been tested using a step method for frequencies of 60 Hz, 0.1 Hz, and dc. The dwell time at each step was chosen so that the aging factor would be the same in both the 60 Hz and 0.1 Hz tests. The data indicated that, while there is a small frequency dependence for liquid nitrogen, there are significant differences for the solid materials studied. Breakdown data for these materials and for model cables will be shown and discussed.

Sauers, Isidor [ORNL; Tuncer, Enis [ORNL; Polyzos, Georgios [ORNL; James, David Randy [ORNL; Ellis, Alvin R [ORNL; Pace, Marshall O [ORNL

2010-01-01T23:59:59.000Z

320

Laser-frequency multiplication  

SciTech Connect

A high quality mode locked pulse train was obtained at 9.55 micrometers, the CO2 wavelength chosen for frequency doubling into the atmospheric window at 4.8 micrometers. The pulse train consists of a 3 micro sec burst of 1.5 nsec pulses separated by 40 nsec, in a TEM(00) mode and with a total energy of 100 mJ. The pulse intensity without focussing is about 3 MW/sq.cm., already quite close to the target intensity of 10 MW/sq.cm. for frequency doubling in a AgGaSe2 crystal. The mode-locked train is obtained by intracavity modulation at 12.5 MHz using a germanium crystal driven with a power of about 30 Watts. Line selection is achieved firstly by the use of a 0.92 mm thick CaF2 plate at the Brewster angle within the cavity, which completely suppresses 10.6 micrometer band radiation. Secondly, a particular rotational line, the P20 at 9.55 micrometers, is selected by the injection of a continuous beam is mode-matched to the pulsed laser cavity using a long focal length lens, and for best line-locking it is necessary to fine tune the length of the pulsed laser resonator. Injection causes substantial depression of the gain switched spike.

Not Available

1991-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "voltage abnormal frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Interaction of Multiple Distributed Energy Resources in Voltage Regulation  

Science Conference Proceedings (OSTI)

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 problem of how to coordinate control multiple DEs to regulate the local voltage in the distribution system is addressed. A control method for voltage regulation using the DE PE controller is presented and based on the proposed control scheme; the voltage regulation of a distribution system with one DE and two DEs are tested, respectively. The factors affecting the gain parameters of the PE controller are investigated. The simulation results show that the parameters of the controller determine its dynamic response for voltage regulation and the factors associated with the network characteristics, such as locations of DEs and the amount of load, affect the impact range of the controller. The research work presented in this paper can be potentially used for the control system design of Smart Grid or Utility of the Future.

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

2008-01-01T23:59:59.000Z

322

OPS 9.6 Investigation of Abnormal Events 8/24/98  

Energy.gov (U.S. Department of Energy (DOE))

The objective of this surveillance is to verify that contractor personnel are effectively investigating abnormal events.  The activities included in this surveillance provide a basis for...

323

Effect of voltage dynamics on response properties in a model of sensory hair cell  

E-Print Network (OSTI)

Sensory hair cells in auditory and vestibular organs rely on active mechanisms to achieve high sensitivity and frequency selectivity. Recent experimental studies have documented self-sustained oscillations in hair cells of lower vertebrates on two distinct levels. First, the hair bundle can undergo spontaneous mechanical oscillations. Second, somatic electric voltage oscillations across the baso-lateral membrane of the hair cell have been observed. We develop a biophysical model of the bullfrog's saccular hair cell consisting of two compartments, mechanical and electrical, to study how the mechanical and the voltage oscillations interact to produce coherent self-sustained oscillations and how this interaction contributes to the overall sensitivity and selectivity of the hair cell. The model incorporates nonlinear mechanical stochastic hair bundle system coupled bi-directionally to a Hodgkin-Huxley type system describing somatic ionic currents. We isolate regions of coherent spontaneous oscillations in the parameter space of the model and then study how coupling between compartments affect sensitivity of the hair cell to external mechanical perturbations. We show that spontaneous electrical oscillations may enhance significantly the sensitivity and selectivity of the hair cell.

Rami Amro; Alexander B. Neiman

2012-09-27T23:59:59.000Z

324

Animation of JILA Frequency Comb Spectroscopy Technique  

Science Conference Proceedings (OSTI)

Animation of JILA Frequency Comb Spectroscopy Technique. The new JILA "frequency comb spectroscopy" technique ...

2012-08-17T23:59:59.000Z

325

Active filters for high-voltage direct-current (HVDC) converter terminals: Final report  

SciTech Connect

This report evaluates the technical and economic feasibility for active filtering of dc-side voltage harmonics and the ac-side current harmonics produced by a HVDC converter. The following designs for the active filter concepts are compared with the existing ac-side and dc-side passive filters used at the Dickinson terminal of the CU HVDC transmission line project: the dc-side active filter consisting of a capacitor coupled current injection source to actively ''neutralize'' the 12th, 24th and the 36th harmonics and, the ac-side active filter designed to provide the same fundamental frequency reactive VARs as the existing passive filters. Controlled currents are injected to actively filter the 11th and the 13th harmonic currents. A cost comparison is made between these active filter designs and existing passive filters supplied by the United Power Association (UPA). 22 figs., 11 tabs.

Mohan, N.; Wong, C.

1988-08-01T23:59:59.000Z

326

High-voltage DC transmission: a power electronics workhorse  

Science Conference Proceedings (OSTI)

Thyristor-based HVDC converter technology is used for highly reliable power transfer across natural or national boundaries or between AC systems designed for different frequencies or incompatible frequency controls. The author discusses the benefits ...

N. G. Hingorani

1996-04-01T23:59:59.000Z

327

Experiment Hazard Class 13.0 - High Voltage  

NLE Websites -- All DOE Office Websites (Extended Search)

3.0 - High Voltage 3.0 - High Voltage Applicability This hazard classification applies to all experiments involving the use of High Voltage Equipment. Other hazard classifications and their associated hazard controls may also apply to experiments in this hazard class. The inspection of electric equipment is covered under the APS Policy For User Electric Equipment Inspections. NOTE: Unless required Argonne training has been completed, users are not authorized to perform electrical work. Experiment Category All Hazard Class 13 experiments are categorized as medium risk experiments. Experiment Hazard Control Verification Statements Engineered Controls - Determined by review and results of a DEEI inspection of the equipment. Procedural Controls - Determined by review and results of a DEEI

328

Proceedings: EPRI/NERC forum on voltage stability  

SciTech Connect

Over the past two decades, the interconnected electric systems serving North America have been increasingly subjected to reductions in generation and transmission capacity reserves, increasing complexity of load character, and the need for power transfer over longer distances. As a result, voltage stability limitations are becoming an important factor for utility personnel to consider when designing and operating an electric system. To address this situation, EPRI and NERC cosponsored a forum to exchange information between the various sectors of the utility industry on voltage control technology. The forum covered available tools and practices; utility operating practices, procedures, and experiences; planning and operating studies; and energy management system (EMS) vendor viewpoints. Participants agreed that a continuing coordinated effort involving all industry groups was needed in the voltage stability area. Attendees also identified specific subject areas of importance to help direct future studies. Individual papers are indexed separately.

Maratukulam, D. (ed.) (Kennedy (Thomas), Florissant, MO (United States))

1993-05-01T23:59:59.000Z

329

Minimization of voltage deviation and power losses in power networks using Pareto optimization methods  

Science Conference Proceedings (OSTI)

Voltage regulation is an important task in electrical engineering for controlling node voltages in a power network. A widely used solution for the problem of voltage regulation is based on adjusting the taps in under load tap changers (ULTCs) power transformers ... Keywords: Multi-objective optimization, Power distribution network, Power losses, Under load tap changers, Voltage regulation

Francisco G. Montoya; Raúl Baños; Consolación Gil; Antonio Espín; Alfredo Alcayde; Julio Gómez

2010-08-01T23:59:59.000Z

330

Elevated voltage level I.sub.DDQ failure testing of integrated circuits  

DOE Patents (OSTI)

Burn in testing of static CMOS IC's is eliminated by I.sub.DDQ testing at elevated voltage levels. These voltage levels are at least 25% higher than the normal operating voltage for the IC but are below voltage levels that would cause damage to the chip.

Righter, Alan W. (Albuquerque, NM)

1996-01-01T23:59:59.000Z

331

Original article: Selective compensation of voltage harmonics in grid-connected microgrids  

Science Conference Proceedings (OSTI)

In this paper, a novel approach is proposed for selective compensation of main voltage harmonics in a grid-connected microgrid. The aim of compensation is to provide a high voltage quality at the point of common coupling (PCC). PCC voltage quality is ... Keywords: Distributed generator (DG), Grid-connected, Microgrid, Voltage harmonics compensation

Mehdi Savaghebi, Juan C. Vasquez, Alireza Jalilian, Josep M. Guerrero, Tzung-Lin Lee

2013-05-01T23:59:59.000Z

332

Requirements for a Standard Test to Rate the Durability of PV Modules at System Voltage (Presentation)  

DOE Green Energy (OSTI)

Degradation modes in photovoltaic modules under system bias voltage stress are described and classified.

Hacke, P.; Terwilliger, K.; Glick, S.; Kempe, M.; Kurtz, S.; Bennett, I.; Kloos, M.

2011-02-01T23:59:59.000Z

333

Voltage Stability/Security Assessment and On-Line Control: Volumes 1-4  

Science Conference Proceedings (OSTI)

To address growing utility concerns of voltage instability and possible voltage collapse, EPRI has developed a new voltage stability analysis package for large power systems, VSTAB. This off-line planning tool provides information on a utility power system's proximity to and mechanism of voltage instability.

1993-05-01T23:59:59.000Z

334

Impact of MOSFET's performance on its threshold voltage and its influence on design of MOS inverters  

Science Conference Proceedings (OSTI)

The aim of this paper is to research the impact of physical parameters which characterize the MOSFET transistors structure on the threshold voltage values and its influence on critical voltage values which characterize digital circuits that contain the ... Keywords: MOSFET parameters, critical values, doped density, enhancement-type NMOS, impurities, narrow-channel, propagation delay, short-channel, threshold voltage, voltage level

Milaim Zabeli; Nebi Caka; Myzafere Limani; Qamil Kabashi

2008-04-01T23:59:59.000Z

335

Frequency mixing crystal  

DOE Patents (OSTI)

In a laser system for converting infrared laser light waves to visible light comprising a source of infrared laser light waves and means of harmonic generation associated therewith for production of light waves at integral multiples of the frequency of the original wave, the improvement of said means of harmonic generation comprising a crystal having the chemical formula X{sub 2} Y(NO{sub 3}){sub 5} {center_dot} 2 nZ{sub 2}O wherein X is selected from the group consisting of Li, Na, K, Rb, Cs, and Tl; Y is selected from the group consisting of Sc, Y, La, Ce, Nd, Pr, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Al, Ga, and In; Z is selected from the group consisting of H and D; and n ranges from 0 to 4.

Ebbers, C.A.; Davis, L.E.; Webb, M.

1990-10-16T23:59:59.000Z

336

Frequency mixing crystal  

DOE Patents (OSTI)

In a laser system for converting infrared laser light waves to visible light comprising a source of infrared laser light waves and means of harmonic generation associated therewith for production of light waves at integral multiples of the frequency of the original wave, the improvement of said means of harmonic generation comprising a crystal having the chemical formula X{sub 2} Y(NO{sub 3}){sub 5} {center dot} 2 nZ{sub 2}O wherein X is selected from the group consisting of Li, Na, K, Rb, Cs, and Tl; Y is selected from the group consisting of Sc, Y, La, Ce, Nd, Pr, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Al, Ga, and In; Z is selected from the group consisting of H and D; and n ranges from 0 to 4.

Ebbers, C.A.; Davis, L.E.; Webb, M.

1990-10-16T23:59:59.000Z

337

Frequency mixing crystal  

DOE Patents (OSTI)

In a laser system for converting infrared laser light waves to visible light comprising a source of infrared laser light waves and means of harmoic generation associated therewith for production of light waves at integral multiples of the frequency of the original wave, the improvement of said means of harmonic generation comprising a crystal having the chemical formula X.sub.2 Y(NO.sub.3).sub.5 .multidot.2 nZ.sub.2 o wherein X is selected from the group consisting of Li, Na, K, Rb, Cs, and Tl; Y is selected from the group consisting of Sc, Y, La, Ce, Nd, Pr, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Al, Ga, and In; Z is selected from the group consisting of H and D; and n ranges from 0 to 4.

Ebbers, Christopher A. (Livermore, CA); Davis, Laura E. (Manteca, CA); Webb, Mark (Salida, CA)

1992-01-01T23:59:59.000Z

338

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

SciTech Connect

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.

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

2011-10-10T23:59:59.000Z

339

Voltage Control Devices on the IEEE 8500 Node Test Feeder  

SciTech Connect

The IEEE Test Cases provide researchers with distribution system models that can be used to validate new analytic methods. The newest of these models is the 8500-node test feeder which contains multiple devices for voltage control. In addition to a substation regulator there are multiple inline regulators as well as capacitor banks. This paper will discuss the detail in which voltage control devises should be modeled when examining large distribution systems. This discussion will include issues associated with power flow analysis for a single time step as well as for time series analysis.

Schneider, Kevin P.; Fuller, Jason C.

2010-01-06T23:59:59.000Z

340

Method of determining the open circuit voltage of a battery in a closed circuit  

SciTech Connect

The open circuit voltage of a battery which is connected in a closed circuit is determined without breaking the circuit or causing voltage upsets therein. The closed circuit voltage across the battery and the current flowing through it are determined under normal load and then a fractional change is made in the load and the new current and voltage values determined. The open circuit voltage is then calculated, according to known principles, from the two sets of values.

Brown, William E. (Walnut Creek, CA)

1980-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "voltage abnormal frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Analysis of Abnormal Wave Records by the Hilbert–Huang Transform Method  

Science Conference Proceedings (OSTI)

The Hilbert–Huang transform method is used in this work to analyze wave records from the North Sea, which include abnormal waves. The analysis of the characteristics of abnormal waves is based on the local decomposition of wave data by using the ...

Albena D. Veltcheva; C. Guedes Soares

2007-09-01T23:59:59.000Z

342

Heart rate variability in preterm neonates with and without abnormal cardiorespiratory events.  

E-Print Network (OSTI)

Heart rate variability in preterm neonates with and without abnormal cardiorespiratory events The heart rate variability (HRV) of preterm neonates undergoing a polysomnography is ana- lyzed in relation experience abnormal cardiorespiratory events, based only on the heart rate recordings during periods without

343

C17: Voltage Impulse Induced Bistable Magnetization Switching and ...  

Science Conference Proceedings (OSTI)

Non-violate dynamic magnetization switch was also realized by voltage impulse ... Concentric Nanoparticles Embedded in Low Temperature Synthesized TiO2 Films .... F2: Development of the On-Line Mechanical Property Prediction System for ... Sintered Nd-Fe-B Magnets by Transmission Electron Microscopy Analysis.

344

Ultra-compact Marx-type high-voltage generator  

DOE Patents (OSTI)

An ultra-compact Marx-type high-voltage generator includes individual high-performance components that are closely coupled and integrated into an extremely compact assembly. In one embodiment, a repetitively-switched, ultra-compact Marx generator includes low-profile, annular-shaped, high-voltage, ceramic capacitors with contoured edges and coplanar extended electrodes used for primary energy storage; low-profile, low-inductance, high-voltage, pressurized gas switches with compact gas envelopes suitably designed to be integrated with the annular capacitors; feed-forward, high-voltage, ceramic capacitors attached across successive switch-capacitor-switch stages to couple the necessary energy forward to sufficiently overvoltage the spark gap of the next in-line switch; optimally shaped electrodes and insulator surfaces to reduce electric field stresses in the weakest regions where dissimilar materials meet, and to spread the fields more evenly throughout the dielectric materials, allowing them to operate closer to their intrinsic breakdown levels; and uses manufacturing and assembly methods to integrate the capacitors and switches into stages that can be arranged into a low-profile Marx generator.

Goerz, David A. (Brentwood, CA); Wilson, Michael J. (Modesto, CA)

2000-01-01T23:59:59.000Z

345

High voltage gas insulated transmission line with continuous particle trapping  

DOE Patents (OSTI)

This invention provides a novel high voltage gas insulated transmission line utilizing insulating supports spaced at intervals with snap-in means for supporting a continuous trapping apparatus and said trapping apparatus having perforations and cutouts to facilitate trapping of contaminating particles and system flexibility.

Cookson, Alan H. (Pittsburgh, PA); Dale, Steinar J. (Monroeville, PA)

1983-01-01T23:59:59.000Z

346

Wire-Extrusion Process Disrupted By Voltage Sags  

Science Conference Proceedings (OSTI)

This PQTN Case Study investigates voltage sags originating from a utility distribution system at a wire-extrusion plant near Cleveland, Ohio that were causing a wire-drawing process to malfunction, resulting in broken tungsten wire and hours of time spent restarting the manufacturing process.

2003-12-31T23:59:59.000Z

347

Smart Solar Home System with Safety Device Low Voltage Alert  

Science Conference Proceedings (OSTI)

For many reasons Bangladeshi people are now using renewable energy. So, solar energy is the best renewable energy till now, in respect of Bangladesh. So using of solar system is common nowadays. Bangladesh Government has taken some steps to make solar ... Keywords: Smart Solar Home System (SSHS), Rooftop, Safety Device, Low voltage alert

Tawheed Hasan; Md. Faysal Nayan; Md. Asif Iqbal; Monzurul Islam

2012-03-01T23:59:59.000Z

348

Current isolating epitaxial buffer layers for high voltage photodiode array  

DOE Patents (OSTI)

An array of photodiodes in series on a common semi-insulating substrate has a non-conductive buffer layer between the photodiodes and the semi-insulating substrate. The buffer layer reduces current injection leakage between the photodiodes of the array and allows optical energy to be converted to high voltage electrical energy.

Morse, Jeffrey D. (Martinez, CA); Cooper, Gregory A. (Pleasant Hill, CA)

2002-01-01T23:59:59.000Z

349

Design of Low Voltage Low Power Operational Amplifier  

Science Conference Proceedings (OSTI)

With the demand of low power applications, running circuits with reduced supply voltage can be of great advantage. Integrated circuit designers start to face a power wall as the most difficult constraints in new technology and circuit development are ... Keywords: Op Amp, CMOS, LVLP

Manju Sandhu; Manju Bala

2012-01-01T23:59:59.000Z

350

High voltage bipolar-CMOS structure using porous silicon  

DOE Patents (OSTI)

A method for integrating a silicon-on-insulator device and a bulk bipolar device on a semiconductor body. The invention simultaneously forms the two regions for the silicon-on-insulator device and the bipolar device. The invention enables a high voltage CMOS power device to be located on the same chip as a bipolar logic device enabling smart power devices.

Guilinger, T.R.; Kelly, M.J.; Tsao, S.S.

1990-01-01T23:59:59.000Z

351

Analysis on DFIG Wind Power System Low-Voltage Ridethrough  

Science Conference Proceedings (OSTI)

Due to the double fed induction generator’s (DFIG) advantage of controlling active and reactive power independently and partial power converter, DFIG is becoming a popular type of wind power generation system. Nowadays, the grid code demands that ... Keywords: VSCF, DFIG, LVRT, Crowbar, Voltage sags

Yulong Wang; Jianlin Li; Shuju Hu; Honghua Xu

2009-04-01T23:59:59.000Z

352

Power and Voltage Smooth Control of Doubly Fed Induction Generator  

Science Conference Proceedings (OSTI)

Doubly-fed induction generator (DFIG) is the leading in wind power technology currently. In this paper, decoupling control of DFIG is studied and a new energy storage device is used in the smooth control of DFIG system's power and voltage. This new method ... Keywords: Doubly fed induction generator, Energy storage device, Decoupling control

An-Ren Ma, Cai-Xia Wang, Zhi-Wen Zhou, Tao Wu

2012-07-01T23:59:59.000Z

353

Low-voltage cathodoluminescence of europium-activated yttrium orthovanadate  

Science Conference Proceedings (OSTI)

Emissive flat panel display systems operating in full color demand higher performance at low voltages (ca. 501000 V) from cathodoluminescent (CL) phosphors than cathode ray tubes require. Hydrothermal synthesis has been suggested as a route to phosphors with improved efficiencies, lower voltage thresholds, and increased saturation power. This hypothesis was tested in europium-doped yttrium orthovanadate (YVO{sub 4}:Eu), an efficient, red emitting CL phosphor. The CL efficiency of YVO{sub 4}:Eu crystallized from aqueous solution at 200{degrees}C is relatively low until it is annealed. The distribution of particle sizes in the low-temperature phosphor is similar to that in material made via a solid-state route, but crystallites remain much smaller (ca. 400 {Angstrom}) until they are annealed. These observations, along with the anomalously strong dependence of CL intensity on europium concentration, support a model in which efficiency principally depends on crystallite size. CL efficiency of both solid state and hydrothermal YVO{sub 4}:Eu increases with voltage at constant power. Surface-bound electrons are likely the dominant influence on efficiency at voltages near threshold. Saturation power is independent of synthetic route. It is apparent that the CL properties of hydrothermally synthesized YVO{sub 4}:Eu are essentially the same as those of YVO{sub 4}:Eu produced via conventional, high-temperature routes.

Phillips, M.L.F.

1995-03-01T23:59:59.000Z

354

Control Techniques to Eliminate Voltage Emergencies in High Performance Processors  

E-Print Network (OSTI)

negligible impact on perfor­ mance and energy. With the ITRS roadmap predicting aggres­ sive drops in supply. At present it is difficult to design a high quality, low impedance power supply system, and industry trends in current variability, often re­ ferred to as the dI/dt problem, can cause supply voltage fluc­ tuations

Martonosi, Margaret

355

Control Techniques to Eliminate Voltage Emergencies in High Performance Processors  

E-Print Network (OSTI)

negligible impact on perfor- mance and energy. With the ITRS roadmap predicting aggres- sive drops in supply. At present it is difficult to design a high quality, low impedance power supply system, and industry trends in current variability, often re- ferred to as the dI/dt problem, can cause supply voltage fluc- tuations

Gupta, Rajiv

356

High Voltage Laboratory Testing of Femtosecond Laser Lightning Diversion  

Science Conference Proceedings (OSTI)

Lightning strikes cost the electric power industry an estimated 1 billion dollars annually in damage and lost revenue. One possible way of protecting critical and susceptible facilities from lightning strikes is to use lasers to trigger and divert lightning along a predetermined path. This report describes laboratory research on the use of ultrashort UV pulses and near IR pulses to trigger high voltage discharge.

1998-12-09T23:59:59.000Z

357

A variable voltage MPPT control method for photovoltaic generation system  

Science Conference Proceedings (OSTI)

To increase the output efficiency of a photovoltaic (PV) generation system it is important to have an efficient maximum power point tracking (MPPT) technique. This paper describes the analysis, design and implementation of an efficient tracking method ... Keywords: maximum power point tracking (MPPT), photovoltaic generation system, pulse-width-modulation (PWM), solar energy, variable voltage

Liu Liqun; Wang Zhixin

2009-04-01T23:59:59.000Z

358

Voltage stability/security assessment and on-line control  

SciTech Connect

Project RP3040-1 was initiated in 1989, and concluded with the release of the Voltage Stability analysis program, VSTAB, in 1992. VSTAB is a production grade program for voltage stability assessment of large complex power systems. During the course of the RP3040-1, much effort was spent in developing a clear understanding of voltage stability and in defining the special modeling and analytical techniques required to accurately capture the phenomenon through simulation. The result was the development of new steady state methods which can complement the dynamic simulation methods currently available with EPRI's Extended Transient/Midterm Stability Program (ETMSP). VSTAB uses an enhanced powerflow combined with a specially developed modal analysis algorithm to provide information regarding both the proximity to, and mechanism of, voltage instability. The program is fast, easy to use, and comprehensive in both modeling and analysis features. This Programmer's Manual documents the structure and code details of VSTAB. It is intended as a reference document for those required to maintain or enhance the VSTAB program. For details on analytical techniques used in the program, readers are directed to the VSTAB Application Guide and Final Report for project RP3040-1.

Morison, G.K.; Gao, B.; Hamadanizadeh, H. (Ontario Hydro, Toronto, ON (Canada))

1993-04-01T23:59:59.000Z

359

Hierarchical Control Scheme for Voltage Unbalance Compensation in Islanded Microgrids  

E-Print Network (OSTI)

Hierarchical Control Scheme for Voltage Unbalance Compensation in Islanded Microgrids Mehdi@et.aau.dk Abstract-- The concept of microgrid hierarchical control is presented, recently. In this paper, a hierarchical scheme which includes primary and secondary control levels is proposed for islanded microgrids

Vasquez, Juan Carlos

360

Low Beam Voltage, 10 MW, L-Band Cluster Klystron  

SciTech Connect

Conceptual design of a multi-beam klystron (MBK) for possible ILC and Project X applications is presented. The chief distinction between this MBK design and existing 10-MW MBK's is the low operating voltage of 60 kV. There are at least four compelling reasons that justify development at this time of a low-voltage MBK, namely (1) no pulse transformer; (2) no oil tank for high-voltage components and for the tube socket; (3) no high-voltage cables; and (4) modulator would be a compact 60-kV IGBT switching circuit. The proposed klystron consists of four clusters containing six beams each. The tube has common input and output cavities for all 24 beams, and individual gain cavities for each cluster. A closely related optional configuration, also for a 10 MW tube, would involve four totally independent cavity clusters with four independent input cavities and four 2.5 MW output ports, all within a common magnetic circuit. This option has appeal because the output waveguides would not require a controlled atmosphere, and because it would be easier to achieve phase and amplitude stability as required in individual SC accelerator cavities.

Teryaev, V.; /Novosibirsk, IYF; Yakovlev, V.P.; /Fermilab; Kazakov, S.; /KEK, Tsukuba; Hirshfield, J.L.; /Yale U. /Omega-P, New Haven

2009-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "voltage abnormal frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Optical frequency combs: From frequency metrology to optical ...  

Science Conference Proceedings (OSTI)

... and to dis- tribute the load of the ... measurements of frequency ratios (ie, energy ratios), and ... accuracy or stability versus power consumption, cost, or ...

2004-01-27T23:59:59.000Z

362

High frequency transformerless electronics ballast using double inductor-capacitor resonant power conversion for gas discharge lamps  

SciTech Connect

A novel high frequency LCLC double resonant electronic ballast has been developed for gas discharge lamp applications. The ballast consists of a half-bridge inverter which switches at zero voltage crossing and an LCLC resonant circuit which converts a low ac voltage to a high ac voltage. The LCLC resonant circuit has two LC stages. The first LC stage produces a high voltage before the lamp is ignited. The second LC stage limits lamp current with the circuit inductance after the lamp is ignited. In another embodiment a filament power supply is provided for soft start up and for dimming the lamp. The filament power supply is a secondary of the second resonant inductor. 27 figs.

Lai, J.S.

1995-06-20T23:59:59.000Z

363

Effective switching frequency multiplier inverter  

SciTech Connect

A switching frequency multiplier inverter for low inductance machines that uses parallel connection of switches and each switch is independently controlled according to a pulse width modulation scheme. The effective switching frequency is multiplied by the number of switches connected in parallel while each individual switch operates within its limit of switching frequency. This technique can also be used for other power converters such as DC/DC, AC/DC converters.

Su, Gui-Jia (Oak Ridge, TN); Peng, Fang Z. (Okemos, MI)

2007-08-07T23:59:59.000Z

364

Frequency Control Performance Measurement and Requirements  

E-Print Network (OSTI)

power systems operations could significantly influence primary frequency control.power system operations could not significantly influence primary frequency control.power system operations. Determination of frequency control

Illian, Howard F.

2011-01-01T23:59:59.000Z

365

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

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.

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

1994-02-01T23:59:59.000Z

366

Infrastructure Failure - Types and Frequency  

U.S. Energy Information Administration (EIA)

Infrastructure Failure - Types and Frequency. Small events that have no impact on supplies Events that require supply/demand responses Events that result in a ...

367

Time and Frequency Division Homepage  

Science Conference Proceedings (OSTI)

... Controlled ClocksTelephone TimeDivision HistoryFrequently Asked Questions (FAQ)Time and Frequency from A to Z: An illustrated glossaryA Walk ...

2013-12-27T23:59:59.000Z

368

Dynamic frequency allocation in fractional frequency reused OFDMA networks  

Science Conference Proceedings (OSTI)

This paper proposes a dynamic fractional frequency reused cell architecture that simplifies the problem of subcarrier allocation with frequency reuse in multicell OFDMA networks. The architecture divides the cell surface into two overlapping geographical ... Keywords: 3G, cellular networks, cross-layer adaptation, data networks, mobile communication systems, opportunistic scheduling, wireless communication

Syed Hussain Ali; Victor C. M. Leung

2009-08-01T23:59:59.000Z

369

Dynamic characteristics of an orthogonal turbine and output-control systems for TPP with high-voltage frequency converter  

SciTech Connect

A mathematical description of a closed control system with allowance for pressure fluctuations in the head system, which makes it possible to analyze the regime stability of orthogonal generating sets at tidal electric power plants when operating in the complete range of heads, outputs, and rotational speeds, and to select parameters of the control system, is obtained for an orthogonal hydroturbine and a generator with a load regulator.

Berlin, V. V.; Murav'ev, O. A.; Golubev, A. V.

2012-03-15T23:59:59.000Z

370

High-voltage supply for neutron tubes in well-logging applications  

DOE Patents (OSTI)

A high voltage supply is provided for a neutron tube used in well logging. The biased pulse supply of the invention combines DC and full pulse techniques and produces a target voltage comprising a substantial negative DC bias component on which is superimposed a pulse whose negative peak provides the desired negative voltage level for the neutron tube. The target voltage is preferably generated using voltage doubling techniques and employing a voltage source which generates bipolar pulse pairs having an amplitude corresponding to the DC bias level.

Humphreys, D.R.

1982-09-15T23:59:59.000Z

371

Stabilized radio-frequency quadrupole  

DOE Patents (OSTI)

A long-vane stabilized radio frequency resonator for accelerating charged particles and including means defining a radio frequency resonator cavity, a plurality of long vanes mounted in the defining means for dividing the cavity into sections, and means interconnecting opposing ones of the plurality of vanes for stabilizing the resonator.

Lancaster, H.D.; Fugitt, J.A.; Howard, D.R.

1982-09-29T23:59:59.000Z

372

Guidelines for Working at Voltages < 240 Volts  

NLE Websites -- All DOE Office Websites (Extended Search)

Guidelines for Working at Voltages < 240 Volts Guidelines for Working at Voltages < 240 Volts February 4, 2005---DRAFT NOTE: Working hot is a LAST ALTERNATIVE. Electrical hot work is defined as: Working on or near exposed conducting parts that are or might become energized at 50V or more. Refer to Electrical Safety Flowchart for Working On or Near Live Parts. Engineered methods to prevent exposed sources of 50V and greater are to be implemented wherever practical. Only QUALIFIED PERSONNEL {as defined in NFPA 70E Article 110.6(D) 2004 edition} as authorized by the CAT/supervisor/division can perform such work. Refer to Qualified Electrical Worker Flow Chart. Training requirements: ES&H 114 (LOTO) / ES&H 375 (NFPA 70E) / ES&H 371 (electrical worker) - Observe Electrical Safe Work Practices. Refer to

373

Methods for improving solar cell open circuit voltage  

DOE Patents (OSTI)

A method for producing a solar cell having an increased open circuit voltage. A layer of cadmium sulfide (CdS) produced by a chemical spray technique and having residual chlorides is exposed to a flow of hydrogen sulfide (H.sub.2 S) heated to a temperature of 400.degree.-600.degree. C. The residual chlorides are reduced and any remaining CdCl.sub.2 is converted to CdS. A heterojunction is formed over the CdS and electrodes are formed. Application of chromium as the positive electrode results in a further increase in the open circuit voltage available from the H.sub.2 S-treated solar cell.

Jordan, John F. (El Paso, TX); Singh, Vijay P. (El Paso, TX)

1979-01-01T23:59:59.000Z

374

Blocking diodes and fuses in low-voltage PV systems  

DOE Green Energy (OSTI)

Instructions and labels supplied with listed PV modules and the requirements of the National Electrical Code (NEC) dictate that a series fuse shall be used to protect the module against backfeed currents. Few of the hundreds of thousands of low-voltage (12, 24, and 48-volt) stand-alone photovoltaic (PV) power systems use series fuses on each module or string of modules. Tests and simulations at the Southwest Technology Development Institute (TDI) and at Sandia National Laboratories (SNL) have established that the absence of these fuses can pose significant fire and safety hazards even on 12-volt PV systems. If the system has sufficient backfeed voltage and current, it is possible that a ground fault in the wiring or inside a module can result in the destruction of a PV module.

Wiles, J.C. [New Mexico State Univ., Las Cruces, NM (United States). Southwest Technology Development Inst.; King, D.L. [Sandia National Labs., Albuquerque, NM (United States). Photovoltaic Systems R and D

1997-11-01T23:59:59.000Z

375

Evaluation of Conservation Voltage Reduction (CVR) on a National Level  

SciTech Connect

Conservation Voltage Reduction (CVR) is a reduction of energy consumption resulting from a reduction of feeder voltage. While there have been numerous CVR systems deployed in North America there has been little substantive analytic analysis of the effect; the majority of the published results are based on empirical field measurements. Since these results are based on empirical measurements it is difficult to extrapolate how this technology will behave on the various types of distribution feeders found throughout the nation. This report has utilized the Taxonomy of Prototypical feeder developed under the Modern Grid Initiative (MGI), now the Modern Grid Strategy (MGS), in order to estimate the benefits of CVR on multiple distribution feeder types. This information will then be used to determine an estimate of the national benefits of a wide scale deployment of CVR.

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

2010-09-29T23:59:59.000Z

376

SRAM leakage suppression by minimizing standby supply voltage  

E-Print Network (OSTI)

Suppressing the leakage current in memories is critical in low-power design. By reducing the standby supply voltage (VDD) to its limit, which is the Data Retention Voltage (DRV), leakage power can be substantially reduced. This paper explores how low DRV can be in a standard low leakage SRAM module and analyzes how DRV is affected by parameters such as process variations, chip temperature, and transistor sizing. An analytical model for DRV as a function of process and design parameters is presented, and forms the base for further design space explorations. This model is verified using simulations as well as measurements from a 4KB SRAM chip in a 0.13?m technology. It is demonstrated that an SRAM cell state can be preserved at sub-300mV standby V DD, with more than 90 % leakage power savings. 1.

Huifang Qin; Yu Cao; Dejan Markovic; Andrei Vladimirescu; Jan Rabaey

2004-01-01T23:59:59.000Z

377

Analysis of Solar Cell Quality Using Voltage Metrics: Preprint  

DOE Green Energy (OSTI)

The highest efficiency solar cells provide both excellent voltage and current. Of these, the open-circuit voltage (Voc) is more frequently viewed as an indicator of the material quality. However, since the Voc also depends on the band gap of the material, the difference between the band gap and the Voc is a better metric for comparing material quality of unlike materials. To take this one step further, since Voc also depends on the shape of the absorption edge, we propose to use the ultimate metric: the difference between the measured Voc and the Voc calculated from the external quantum efficiency using a detailed balance approach. This metric is less sensitive to changes in cell design and definition of band gap. The paper defines how to implement this metric and demonstrates how it can be useful in tracking improvements in Voc, especially as Voc approaches its theoretical maximum.

Toberer, E. S.; Tamboli, A. C.; Steiner, M.; Kurtz, S.

2012-06-01T23:59:59.000Z

378

Frequency Conversion of Entangled State  

E-Print Network (OSTI)

The quantum characteristics of sum-frequency process in an optical cavity with an input signal optical beam, which is a half of entangled optical beams, are analyzed. The calculated results show that the quantum properties of the signal beam can be maintained after its frequency is conversed during the intracavity nonlinear optical interaction. The frequency-conversed output signal beam is still in an entangled state with the retained other half of initial entangled beams. The resultant quantum correlation spectra and the parametric dependences of the correlations on the initial squeezing factor, the optical losses and the pump power of the sum-frequency cavity are calculated. The proposed system for the frequency conversion of entangled state can be used in quantum communication network and the calculated results can provide direct references for the design of experimental systems.

Aihong Tan; Xiaojun Jia; Changde Xie

2006-03-01T23:59:59.000Z

379

General Interest NIST Time and Frequency Publications  

Science Conference Proceedings (OSTI)

... Time and Frequency Users Manual A detailed ... Fundamentals of Time and Frequency An overview of ... Lombardi, The Mechatronics Handbook, 2001. ...

2012-01-31T23:59:59.000Z

380

High Frequency Power Modulation - TRIMET Smelters Provide ...  

Science Conference Proceedings (OSTI)

Presentation Title, High Frequency Power Modulation - TRIMET Smelters Provide Primary Control Power for Stabilizing the Frequency in the Electricity Grid.

Note: This page contains sample records for the topic "voltage abnormal frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Field Guide: Compressors for High-Voltage Circuit Breakers  

Science Conference Proceedings (OSTI)

High-voltage circuit breakers (HVCBs) perform essential protection and control functions on power transmission networks. Circuit breakers have multiple components that must operate in concert in order for the breaker to perform properly. If one component, such as the air or hydraulic system, does not operate correctly, the circuit breaker may misoperate or fail, possibly resulting in equipment damage or an outageboth expensive consequences. To help utilities prevent such undesirable events, this field gu...

2010-12-22T23:59:59.000Z

382

Field Guide: Compressors for High-Voltage Circuit Breakers  

Science Conference Proceedings (OSTI)

High-voltage circuit breakers (HVCBs) perform essential protection and control functions on power transmission networks. Circuit breakers have multiple components that must operate in concert in order for the breaker to perform properly. If one component, such as the air or hydraulic system, does not operate correctly, the circuit breaker may misoperate or fail, possibly resulting in equipment damage or an outage—both expensive consequences. To help ...

2012-12-14T23:59:59.000Z

383

Nano-Composite Dielectrics on Medium-Voltage Model Cables  

Science Conference Proceedings (OSTI)

EPRI early recognized the potential for nanotechnology in power distribution and started a program in 2003 to explore the possibilities of using the technology to enhance the properties of high-voltage (HV) cable dielectrics based on both polyethylene and on ethylene-propylene rubber. This research resulted in encouraging findings, particularly for a formulation based on functionalized silicon dioxide nanoparticles in a cross-linked polyethylene (XLPE) polymer. Following this success, EPRI entered into a...

2007-12-19T23:59:59.000Z

384

High Voltage Direct Current (HVDC) Transmission Reference Book  

Science Conference Proceedings (OSTI)

The EPRI High-Voltage Direct Current (HVDC) Transmission Reference Book is a state-of-the-art guidebook that provides transmission companies with a comprehensive, single source of technical information and guidance for designing, building, operating, and extending the life of HVDC transmission systems. The book joins the landmark series of EPRI power delivery reference books. These comprehensive guidebooks—each printed with a distinctive colored cover—document and distill the ...

2012-12-31T23:59:59.000Z

385

Field Guide: High-Voltage Circuit Breaker Compressors – 2013 Update  

Science Conference Proceedings (OSTI)

High-voltage circuit breakers (HVCBs) perform essential protection and control functions on power transmission networks. Circuit breaker mechanisms have multiple components that must operate in concert in order for the breaker to perform properly. If one component, such as the air or hydraulic system, does not operate correctly, the circuit breaker may mis-operate or fail. A circuit breaker mis-operation may cause equipment damage and outages—both ...

2013-12-19T23:59:59.000Z

386

Advanced Voltage Control Strategies for High Penetration of Distributed Generation  

Science Conference Proceedings (OSTI)

This research addresses advanced voltage control strategies for inverter-connected distributed generation. The emphasis is on photovoltaic (PV) generation, and results also apply to distributed wind, fuel cells, micro-turbines, and battery systems that are connected to the grid through an inverter. In related work, the Electric Power Research Institute (EPRI) identified a set of high-priority functions for distributed generation. These included reactive power control such as intelligent and autonomous vo...

2010-12-31T23:59:59.000Z

387

High-Voltage Direct Current Line Conductor Optimization  

Science Conference Proceedings (OSTI)

Overhead transmission lines are designed to last for 40 years. Many ac lines in service today in North America are 70 or more years old. This survival rate is a result of conservative utility design practices and detailed product specifications. This reliability record has occurred despite a wide range of conductor types and sizes. In the present transmission system, there are far fewer high-voltage direct current (HVDC) lines, but those that have been designed and built have been similarly successful in...

2011-12-21T23:59:59.000Z

388

Fiber optic current monitor for high-voltage applications  

DOE Patents (OSTI)

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.

Renda, G.F.

1992-04-21T23:59:59.000Z

389

765kV Transmission line Voltage gradient  

E-Print Network (OSTI)

Corona ring Transmission lines Nowadays, due to the ever increasing energy consumption and power supply optimization, it is required to construct new power plants, substations and transmission lines. In Iran, also, because of increasing demand for electrical energy, for a significant power loss reduction in power transmission over long distances, and to construct high transmission lines that lead to reduction in the economic costs of transmission lines, the transmission lines must be considered at extra high voltage (EHV) levels. These EHV levels should be compared with the low voltage levels in order to extract the benefits. Therefore, in this paper, a review has been conducted on the types of 765 kV transmission lines used in different countries and a comparison between them and the low voltage levels have been performed. Accordingly, the advantages of EHV transmission lines are summarized. Finally, designing a line of 765 kV single-circuit with 6 conductors per bundle based on existing standards is presented.

unknown authors

2012-01-01T23:59:59.000Z

390

Advanced Gate Drive for the SNS High Voltage Converter Modulator  

SciTech Connect

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.

Nguyen, M.N.; Burkhart, C.; Kemp, M.A.; /SLAC; Anderson, D.E.; /Oak Ridge

2009-05-07T23:59:59.000Z

391

Near independence of OLED operating voltage on transport layer thickness  

SciTech Connect

We report organic light emitting devices (OLEDs) with weak drive voltage dependence on the thickness of the hole transport layer (HTL) for thicknesses up to 1150 Å using the N,N?-Bis(naphthalen-1-yl)-N,N?-bis(phenyl)-benzidine (?-NPD) and N,N'-bis(3-methyl phenyl)-N,N'-diphenyl-[1,1'-biphenyl]-4,4'diamine (TPD), both of which have hole mobilities in the range of 2 × 10-3 cm2V-1s-1. Lower mobility HTL materials show larger operating voltage dependence on thickness. The near independence of the operating voltage for high mobility transport material thickness was only observed when the energy barrier for charge injection into the transport material was minimized. To ensure low injection barriers, a thin film of 2-(3-(adamantan-1-yl)propyl)-3,5,6-trifluorotetracyanoquinodimethane (F3TCNQ-Adl) was cast from solution onto the ITO surface. These results indicate that thick transport layers can be integrated into OLED stacks without the need for bulk conductivity doping.

Swensen, James S.; Wang, Liang (Frank) [Frank; Polikarpov, Evgueni; Rainbolt, James E.; Koech, Phillip K.; Cosimbescu, Lelia; Padmaperuma, Asanga B.

2013-01-01T23:59:59.000Z

392

Low-frequency RF Coupling To Unconventional (Fat Unbalanced) Dipoles  

SciTech Connect

The report explains radio frequency (RF) coupling to unconventional dipole antennas. Normal dipoles have thin equal length arms that operate at maximum efficiency around resonance frequencies. In some applications like high-explosive (HE) safety analysis, structures similar to dipoles with ''fat'' unequal length arms must be evaluated for indirect-lightning effects. An example is shown where a metal drum-shaped container with HE forms one arm and the detonator cable acts as the other. Even if the HE is in a facility converted into a ''Faraday cage'', a lightning strike to the facility could still produce electric fields inside. The detonator cable concentrates the electric field and carries the energy into the detonator, potentially creating a hazard. This electromagnetic (EM) field coupling of lightning energy is the indirect effect of a lightning strike. In practice, ''Faraday cages'' are formed by the rebar of the concrete facilities. The individual rebar rods in the roof, walls and floor are normally electrically connected because of the construction technique of using metal wire to tie the pieces together. There are two additional requirements for a good cage. (1) The roof-wall joint and the wall-floor joint must be electrically attached. (2) All metallic penetrations into the facility must also be electrically connected to the rebar. In this report, it is assumed that these conditions have been met, and there is no arcing in the facility structure. Many types of detonators have metal ''cups'' that contain the explosives and thin electrical initiating wires, called bridge wires mounted between two pins. The pins are connected to the detonator cable. The area of concern is between the pins supporting the bridge wire and the metal cup forming the outside of the detonator. Detonator cables usually have two wires, and in this example, both wires generated the same voltage at the detonator bridge wire. This is called the common-mode voltage. The explosive component inside a detonator is relatively sensitive, and any electrical arc is a concern. In a safety analysis, the pin-to-cup voltage, i.e., detonator voltage, must be calculated to decide if an arc will form. If the electric field is known, the voltage between any two points is simply the integral of the field along a line between the points. Eq. 1.1. For simplicity, it is assumed that the electric field and dipole elements are aligned. Calculating the induced detonator voltage is more complex because of the field concentration caused by metal components. If the detonator cup is not electrically connected to the metal HE container, the portion of the voltage generated by the dipole at the detonator will divide between the container-to-cup and cup-to-pin gaps. The gap voltages are determined by their capacitances. As a simplification, it will be assumed the cup is electrically attached, short circuited, to the HE container. The electrical field in the pin-to-cup area is determined by the field near the dipole, the length of the dipole, the shape of the arms, and the orientation of the arms. Given the characteristics of a lightning strike and the inductance of the facility, the electric fields in the ''Faraday cage'' can be calculated. The important parameters for determining the voltage in an empty facility are the inductance of the rebars and the rate of change of the current, Eq. 1.3. The internal electric fields are directly related to the facility voltages, however, the electric fields in the pin-to-cup space is much higher than the facility fields because the antenna will concentrate the fields covered by the arms. Because the lightning current rise-time is different for every strike, the maximum electric field and the induced detonator voltage should be described by probability distributions. For pedantic purposes, the peak field in the simulations will be simply set to 1 V/m. Lightning induced detonator voltages can be calculated by scaling up with the facility fields. Any metal object around the explosives, such as a work stand, will also distort the electric

Ong, M M; Brown, C G; Perkins, M P; Speer, R D; Javedani, J B

2010-12-07T23:59:59.000Z

393

Research on Low-Voltage Ride-Through Technology of Doubly-Fed VSCF Wind Power Generation System  

Science Conference Proceedings (OSTI)

Currently, some of the variable speed wind turbine on market have some low-voltage through capacity?LVRT?, but do not have dynamic reactive power support capacity under fault. DFIG can’t provide dynamic voltage support, in addition, ... Keywords: wind power, voltage dip, low voltage ride-through (LVRT), transient voltage control, rotor-side converter

Bao Wei; Yin Zhongdong

2009-10-01T23:59:59.000Z

394

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

E-Print Network (OSTI)

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 ...

Moawwad, Ahmed

395

BB5, Nearly Ideal Current-Voltage Characteristics of Schottky Barrier ...  

Science Conference Proceedings (OSTI)

Recently, high-quality GaN free-standing substrates are available by various methods. ... Current-voltage (I-V) characteristics and capacitance-voltage (C-V) ...

396

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

E-Print Network (OSTI)

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. ...

Guyton, Matthew C. (Matthew Christopher)

2010-01-01T23:59:59.000Z

397

Voltage holding study of 1 MeV accelerator for ITER neutral beam injectora)  

Science Conference Proceedings (OSTI)

Voltage holding test on MeV accelerator indicated that sustainable voltage was a half of that of ideal quasi-Rogowski electrode. It was suggested that the emission of the clumps is enhanced by a local electric field concentration

M. Taniguchi; M. Kashiwagi; N. Umeda; M. Dairaku; J. Takemoto; H. Tobari; K. Tsuchida; H. Yamanaka; K. Watanabe; A. Kojima; M. Hanada; K. Sakamoto; T. Inoue

2012-01-01T23:59:59.000Z

398

Monitoring Volume Transport through Measurement of Cable Voltage across the Korea Strait  

Science Conference Proceedings (OSTI)

Voltage induced by the Tsushima Current on an abandoned submarine telephone cable between Pusan, Korea, and Hamada, Japan, has been measured since March 1998 in order to monitor the volume transport through the Korea Strait. Voltage has a good ...

Kuh Kim; Sang Jin Lyu; Young-Gyu Kim; Byung Ho Choi; Keisuke Taira; Henry T. Perkins; William J. Teague; Jeffrey W. Book

2004-04-01T23:59:59.000Z

399

Lipon Coatings for High Voltage and High Temperature Li-Ion ...  

use of high-capacity and high-voltage cathode materials, but charging to voltages approaching 4.5-5V invariably causes rapid loss of capacity with cycling.

400

Strategies for Voltage Control and Transient Stability Assessment  

SciTech Connect

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

Hiskens, Ian A.

2013-09-25T23:59:59.000Z

Note: This page contains sample records for the topic "voltage abnormal frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

A Hybrid Framework for Voltage Security Assessment Integrating Simulation and Measurement Based Approaches  

Science Conference Proceedings (OSTI)

Voltage stability is the ability of a power system to maintain adequate voltage magnitudes at buses, which is a major concern in daily power system operations and a leading factor to limit power transfers in a prevailing open-access environment. Currently, simulation-based voltage security assessment (VSA) tools are applied widely by electric utilities to analyze either steady-state or transient voltage stability issues. Those VSA tools can help operators foresee the next critical ...

2012-12-31T23:59:59.000Z

402

Intelligent robust control of hybrid distributed generation system under voltage sag  

Science Conference Proceedings (OSTI)

In this paper, design of control strategy for hybrid fuel cell/energy storage distributed power generation system during voltage sag has been presented. The proposed control strategy allows hybrid distributed generation system works properly when a voltage ... Keywords: Energy storage, Fuel cell, Fuzzy sliding control, Hybrid distributed generation, Lyapanov, Neuro-fuzzy, Voltage sag

Amin Hajizadeh; Masoud Aliakbar Golkar

2010-12-01T23:59:59.000Z

403

Connectivity and Bidirectional Energy Transfer in DC Microgrid Featuring Different Voltage Characteristics  

Science Conference Proceedings (OSTI)

In this paper, the connectivity issues related to linking two DC buses featuring different voltage characteristics, in terms of voltage level and ripple, in a DC micro grid are identified, analyzed and discussed. A controlled DC-DC converter was used ... Keywords: Bidirectional energy transfer, buck-boost converter, DC distribution systems, DC microgrids, voltage ripple

Mustafa Farhadi, Ahmed Mohamed, Osama Mohammed

2013-04-01T23:59:59.000Z

404

Modeling and simulation of new configuration of dynamic voltage restorer for power quality improvement  

Science Conference Proceedings (OSTI)

The dynamic voltage restorer (DVR) is a custom device that is used to maintain the voltage at the load terminals from various power quality problems from a disturbed incoming supply. In this paper, a novel control strategy is described for mitigation ... Keywords: custom device, dynamic voltage restorer (DVR), power quality, sags, sensitive loads, swells

Rosli Omar; Nasrudin Abdul Rahim

2011-04-01T23:59:59.000Z

405

Currents' Physical Components (CPC) In Circuits with Nonsinusoidal Voltages and Currents  

E-Print Network (OSTI)

voltages and currents. It is true only for balanced loads supplied with a symmetrical voltage. However{ || || || || || || }P u u uY Y Y+ + . (20) The supply voltage is sinusoidal and symmetrical, thus RS ST TR R for energy permanent conversion in the load with power P. The remaining part of the supply current, i ­ ia

Czarnecki, Leszek S.

406

Energy Minimization Using Multiple Supply Voltages Jui-Ming Chang and Massoud Pedram  

E-Print Network (OSTI)

Energy Minimization Using Multiple Supply Voltages Jui-Ming Chang and Massoud Pedram Department and energy costs of these level shifters must be taken into account when comparing a multiple-supply voltage a dynamic programming technique for solv- ing the multiple supply voltage scheduling problem in both non

Pedram, Massoud

407

Charging-choke circuit with a crowbar for precision control of voltage  

DOE Patents (OSTI)

The operation of a circuit using a charging choke to obtain dc voltages is improved by constructing the circuit to be capable of producing a higher voltage than the desired value and crowbarring the charging choke when the load voltage reaches the desired value.

Praeg, W.F.

1975-11-25T23:59:59.000Z

408

Analysis the operation of DVR in voltage sag mitigation using EMTP  

Science Conference Proceedings (OSTI)

According to the reports, voltage sag is the most probable voltage problem in the network. As the number of sensitive loads increases rapidly the demand for a reliable and cost effective solution also has been increased. In this paper we are going to ... Keywords: DVR, custom power, distribution network, voltage sag

H. Monsef; B. Tamimi

2005-03-01T23:59:59.000Z

409

Voltage control of emerging distribution systems with induction motor loads using robust LQG approach  

E-Print Network (OSTI)

mode" in emerging distribution systems. The small-signal stability analysis indicates that load voltageVoltage control of emerging distribution systems with induction motor loads using robust LQG has significant performance to improve the voltage profile of the distributed generation system

Pota, Himanshu Roy

410

CMOS flash analog-to-digital converter for high speed and low voltage applications  

Science Conference Proceedings (OSTI)

A CMOS flash analog-to-digital converter (ADC) designed for high speed and low voltage is presented. Using the Threshold Inverter Quantization (TIQ) comparator technique, a flash ADC can be applied to low supply voltage. A fat tree encoder that has signal ... Keywords: TIQ comparator, analog-to-digital converter, fat tree encoder, flash ADC, high speed, low voltage

Jincheol Yoo; Kyusun Choi; Jahan Ghaznavi

2003-04-01T23:59:59.000Z

411

AUTO ID FUTURE - FREQUENCY AGNOSTIC  

E-Print Network (OSTI)

Identification of information is one key to the development of intelligent decision systems of the future. Frequency agnostic automatic identification is only one step in the physical world to make physical objects identify ...

DATTA, SHOUMEN

412

Frequency regulator for synchronous generators  

DOE Patents (OSTI)

The present invention is directed to a novel frequency regulator which controls a generator output frequency for variations in both the input power to the generator and the power supplied to an uncontrolled external load. The present invention further includes over current and current balance protection devices which are relatively inexpensive to manufacture, which may be encapsulated to provide protection from the operating environment and which respond more quickly than previously known electromechanical devices.

Karlicek, Robert F. (1920 Camino Centroloma, Fullerton, CA 92633)

1982-01-01T23:59:59.000Z

413

Frequency regulator for synchronous generators  

DOE Patents (OSTI)

The present invention is directed to a novel frequency regulator which controls a generator output frequency for variations in both the input power to the generator and the power supplied to an uncontrolled external load. The present invention further includes over current and current balance protection devices which are relatively inexpensive to manufacture, which may be encapsulated to provide protection from the operating environment and which respond more quickly than previously known electromechanical devices. 11 figs.

Karlicek, R.F.

1982-08-10T23:59:59.000Z

414

A model for the critical voltage for electrical degradation of GaN high electron mobility transistors  

E-Print Network (OSTI)

We have found that there is a critical drain-to-gate voltage beyond which GaN high-electron mobility transistors start to degrade in electrical-stress experiments. The critical voltage depends on the detailed voltage biasing ...

Joh, Jungwoo

415

Effect of the change in the load resistance on the high voltage pulse transformer of the intense electron-beam accelerators  

Science Conference Proceedings (OSTI)

A high voltage pulse transformer (HVPT) is usually used as a charging device for the pulse forming line (PFL) of intense electron-beam accelerators (IEBAs). Insulation of the HVPT is one of the important factors that restrict the development of the HVPT. Until now, considerable effort has been focused on minimizing high field regions to avoid insulation breakdown between windings. Characteristics of the HVPT have been widely discussed to achieve these goals, but the effects of the PFL and load resistance on HVPT are usually neglected. In this paper, a HVPT is used as a charging device for the PFL of an IEBA and the effect of the change in the load resistance on the HVPT of the IEBA is presented. When the load resistance does not match the wave impedance of the PFL, a high-frequency bipolar oscillating voltage will occur, and the amplitude of the oscillating voltage will increase with the decrease in the load resistance. The load resistance approximates to zero and the amplitude of the oscillating voltage is much higher. This makes it easier for surface flashover along the insulation materials to form and decrease the lifetime of the HVPT.

Cheng Xinbing; Liu Jinliang; Qian Baoliang; Zhang Yu; Zhang Hongbo [College of Photoelectrical Science and Engineering, National University of Defense Technology, Hunan 410073 (China)

2009-11-15T23:59:59.000Z

416

Nuclear Maintenance Applications Center: Post-Trip Voltage Prediction at Nuclear and Other Generating Stations  

Science Conference Proceedings (OSTI)

The objective of this Electric Power Research Institute (EPRI) project is to investigate the possibility of predicting the switchyard voltage in a nuclear power plant (NPP) following a trip of a nuclear unit. Two methods of post-trip voltage prediction are investigated. The first method, called the V-Q method, uses minimal local plant information (such as unit operating conditionsactive and reactive power output and pre-trip voltage) to predict post-trip voltage based on the sensitivity of voltage to the...

2009-06-30T23:59:59.000Z

417

Voltage Node Arcing in the ICRH Antenna Vacuum Transmission Lines at JET  

Science Conference Proceedings (OSTI)

The observation of parasitic low-VSWR activity during operations of JET RF plant and the damage caused by arcing at the voltage-node in the vacuum transmission line (VTL) in 2004 highlight the importance of the problem of low-voltage breakdown in the ICRH systems. Simulations demonstrate little response of the RF circuit to the voltage-node arcing which explains why it remains largely unnoticed and complicates the design of protection systems. Analysis of the damage pattern produced by the voltage-node arcing suggests that multipactor-related phenomena occurring at elevated voltage thresholds in conditions of unfavorable VTL geometry are most plausible arc-provoking factors.

Monakhov, I.; Graham, M.; Mayoral, M.-L.; Nicholls, K.; Walden, A. [Euratom/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB (United Kingdom); Bobkov, V. [Max-Planck Institut fuer Plasmaphysik, EURATOM Association, D-85748 Garching (Germany)

2007-09-28T23:59:59.000Z

418

Induction of nuclear fission by high-voltage application  

E-Print Network (OSTI)

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.

Hirokazu Maruyama

2007-11-20T23:59:59.000Z

419

Light-weight DC to very high voltage DC converter  

DOE Patents (OSTI)

A DC-DC converter capable of generating outputs of 100 KV without a transformer comprises a silicon opening switch (SOS) diode connected to allow a charging current from a capacitor to flow into an inductor. When a specified amount of charge has flowed through the SOS diode, it opens up abruptly; and the consequential collapsing field of the inductor causes a voltage and current reversal that is steered into a load capacitor by an output diode. A switch across the series combination of the capacitor, inductor, and SOS diode closes to periodically reset the SOS diode by inducing a forward-biased current.

Druce, Robert L. (Union City, CA); Kirbie, Hugh C. (Dublin, CA); Newton, Mark A. (Livermore, CA)

1998-01-01T23:59:59.000Z

420

Light-weight DC to very high voltage DC converter  

DOE Patents (OSTI)

A DC-DC converter capable of generating outputs of 100 KV without a transformer comprises a silicon opening switch (SOS) diode connected to allow a charging current from a capacitor to flow into an inductor. When a specified amount of charge has flowed through the SOS diode, it opens up abruptly; and the consequential collapsing field of the inductor causes a voltage and current reversal that is steered into a load capacitor by an output diode. A switch across the series combination of the capacitor, inductor, and SOS diode closes to periodically reset the SOS diode by inducing a forward-biased current. 1 fig.

Druce, R.L.; Kirbie, H.C.; Newton, M.A.

1998-06-30T23:59:59.000Z

Note: This page contains sample records for the topic "voltage abnormal frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Light-induced voltage alteration for integrated circuit analysis  

DOE Patents (OSTI)

An apparatus and method are described for analyzing an integrated circuit (IC), The invention uses a focused light beam that is scanned over a surface of the IC to generate a light-induced voltage alteration (LIVA) signal for analysis of the IC, The LIVA signal may be used to generate an image of the IC showing the location of any defects in the IC; and it may be further used to image and control the logic states of the IC. The invention has uses for IC failure analysis, for the development of ICs, for production-line inspection of ICs, and for qualification of ICs.

Cole, Jr., Edward I. (Albuquerque, NM); Soden, Jerry M. (Placitas, NM)

1995-01-01T23:59:59.000Z

422

Self-monitoring high voltage transmission line suspension insulator  

DOE Patents (OSTI)

A high voltage transmission line suspension insulator (18 or 22) which monitors its own dielectric integrity. A dielectric rod (10) has one larger diameter end fitting attachable to a transmission line and another larger diameter end fitting attachable to a support tower. The rod is enclosed in a dielectric tube (14) which is hermetically sealed to the rod's end fittings such that a liquidtight space (20) is formed between the rod and the tube. A pressurized dielectric liquid is placed within that space. A discoloring dye placed within this space is used to detect the loss of the pressurized liquid.

Stemler, Gary E. (Vancouver, WA); Scott, Donald N. (Vancouver, WA)

1981-01-01T23:59:59.000Z

423

Worldwide reliability surveys of high voltage circuit breakers  

Science Conference Proceedings (OSTI)

This article reports on the results of two CIGRE 13.06 Working Group worldwide surveys of the reliability of high voltage circuit breakers, 63 kV and above. The first inquiry included 78,000 breaker-years of ``in service data`` from 102 utilities in 22 countries during the years 1974--1977 and included all interrupting technologies. The second inquiry included 70,708 breaker-years from 132 utilities in 22 countries for the years 1988--1991 and only included single-pressure SF6 breakers, because this is what most utilities are now buying. Thirty-one US utilities submitted data.

Heising, C.R.

1995-05-01T23:59:59.000Z

424

Outdoor PV Module Degradation of Current-Voltage Parameters: Preprint  

DOE Green Energy (OSTI)

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.

Smith, R. M.; Jordan, D. C.; Kurtz, S. R.

2012-04-01T23:59:59.000Z

425

High-Voltage Power Supply System for Laser Isotope Separation  

SciTech Connect

This report presents several concepts for Laser High-Voltage Power Supply (HVPS) Systems for a Laser Isotope Separation facility. Selection of equipments and their arrangement into operational systems is based on proven designs and on application concepts now being developed. This report has identified a number of alternative system arrangements and has provided preliminary cost estimates for each. The report includes a recommendation for follow-on studies that will further define the optimum Laser HVPS Systems. Brief descriptions are given of Modulator/Regulator circuit trade-offs, system control interfaces, and their impact on costs.

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

1979-06-26T23:59:59.000Z

426

High Voltage Direct Current Live Line and Insulator Testing  

Science Conference Proceedings (OSTI)

This report has two main parts. The focus of the first part is on live work in overhead high-voltage direct current (HVDC) lines operating above 100 kV dc. It does not address issues related to lines for electric transport that typically operate below 60 kV dc worldwide. In addition, this first part of the report is not a detailed treatise on live work but, rather, addresses the main issues related to dc live work. More detailed information on the general topic of live work can be found in the references...

2011-12-23T23:59:59.000Z

427

Development of static and simulation programs for voltage stability studies of bulk power system  

SciTech Connect

In the analysis and evaluation of voltage stability, it is necessary to accurately identify the stability margin at each load point under specific system configuration or power balance condition. Voltage stability margin can be basically identified by the multi-solution load flow calculation method. When predicted by this static analysis that voltage instability may occur, time domain simulation will be required which includes the models of various control equipments related with system voltage profile. To deal with this, the following two analytical computer codes shown below were developed. (1) Voltage stability static analysis computer code employing a new load flow calculation method. (2) Time domain long term simulation computer code for voltage stability. These computer codes can also calculate the voltage stability index at each load point which is based on the margin to the stability power limit at each load point. The practicality of these codes developed were verified by applying to the IEEE-118 test system.

Nagao, T.; Tanaka, K.; Takenaka, K. [Central Research Inst. of Electric Power Industry, Tokyo (Japan)

1997-02-01T23:59:59.000Z

428

Commercialization of Medium Voltage HTS Triax TM Cable Systems  

SciTech Connect

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.

Knoll, David

2012-12-31T23:59:59.000Z

429

Miniature UV lamp excited by subnanosecond voltage pulses  

SciTech Connect

Energy, time, and spectral characteristics of emission of the second positive system of N{sub 2} molecules in gaseous nitrogen, Ar - N{sub 2} mixture, and air are investigated. An FPG-10 generator with voltage pulse FWHM of 200 and 400 ps and matched-load amplitudes of 14 and 6 kV, respectively, is used to excite gases. It is shown that excitation can be performed in two regimes using this generator. In the first regime a diffuse discharge is formed at atmospheric pressure, which opens ways to design miniature nanosecond UV lamps. A diffuse discharge is formed due to the generation of runaway electrons, with the aid of electrodes having a small radius of curvature and voltage pulses with a sharp leading edge. In the second regime an elevated average radiation power is obtained under excitation by a barrier discharge. However, the operating pressure is lower in this case, and the sizes of the emitting region and the UV pulse width significantly increase. (laser applications and other topics in quantum electronics)

Erofeev, M V; Baksht, E Kh; Tarasenko, Viktor F; Shut'ko, Yu V [Institute of High Current Electronics, Siberian Branch, Russian Academy of Sciences, Tomsk (Russian Federation)

2010-08-27T23:59:59.000Z

430

Bi-directional power control system for voltage converter  

DOE Patents (OSTI)

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

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

1999-01-01T23:59:59.000Z

431

Bi-directional power control system for voltage converter  

DOE Patents (OSTI)

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

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

1999-05-11T23:59:59.000Z

432

Frequency  

Science Conference Proceedings (OSTI)

... noise terms are the result of environmental changes affecting ... respond to changes in environment, so this ... is probably of broadest concern, but some ...

2002-11-19T23:59:59.000Z

433

Radio frequency circuits for wireless receiver front-ends  

E-Print Network (OSTI)

The beginning of the 21st century sees great development and demands on wireless communication technologies. Wireless technologies, either based on a cable replacement or on a networked environment, penetrate our daily life more rapidly than ever. Low operational power, low cost, small form factor, and function diversity are the crucial requirements for a successful wireless product. The receiver??s front-end circuits play an important role in faithfully recovering the information transmitted through the wireless channel. Bluetooth is a short-range cable replacement wireless technology. A Bluetooth receiver architecture was proposed and designed using a pure CMOS process. The front-end of the receiver consists of a low noise ampli?er (LNA) and mixer. The intermediate frequency was chosen to be 2MHz to save battery power and alleviate the low frequency noise problem. A conventional LNA architecture was used for reliability. The mixer is a modi?ed Gilbert-cell using the current bleeding technique to further reduce the low frequency noise. The front-end draws 10 mA current from a 3 V power supply, has a 8.5 dB noise ?gure, and a voltage gain of 25 dB and -9 dBm IIP3. A front-end for dual-mode receiver is also designed to explore the capability of a multi-standard application. The two standards are IEEE 802.11b and Bluetooth. They work together making the wireless experience more exciting. The front-end is designed using BiCMOS technology and incorporating a direct conversion receiver architecture. A number of circuit techniques are used in the front-end design to achieve optimal results. It consumes 13.6 mA from a 2.5 V power supply with a 5.5 dB noise ?gure, 33 dB voltage gain and -13 dBm IIP3. Besides the system level contributions, intensive studies were carried out on the development of quality LNA circuits. Based on the multi-gated LNA structure, a CMOS LNA structure using bipolar transistors to provide linearization is proposed. This LNA con?guration can achieve comparable linearity to its CMOS multi-gated counterpart and work at a higher frequency with less power consumption. A LNA using an on-chip transformer source degeneration is proposed to realize input impedance matching. The possibility of a dual-band cellular application is studied. Finally, a study on ultra-wide band (UWB) LNA implementation is performed to explore the possibility and capability of CMOS technology on the latest UWB standard for multimedia applications.

Xin, Chunyu

2004-08-01T23:59:59.000Z

434

Report to Congress on abnormal occurrences, April--June 1993. Volume 16, No. 2  

SciTech Connect

Section 208 of the Energy Reorganization Act of 1974 identifies an abnormal occurrence as an unscheduled incident or event that the Nuclear Regulatory Commission determines to be significant from the standpoint of public health and safety and requires a quarterly report of such events to be made to Congress. This report covers the period April through June 1993, and discusses four abnormal occurrences at NRC-licensed facilities, three involving medical brachytherapy misadministrations and one involving a research reactor that operated without a safety system. One pool irradiation facility contamination event, two medical misadministrations (one ``sodium iodide`` and one brachytherapy), and one industrial radiographer overexposure event that were reported by NRC Agreement States are also discussed. The report also contains information updating one previously reported abnormal occurrence and information on three other events of interest.

Not Available

1993-09-01T23:59:59.000Z

435

Environmental impact assessment of abnormal events: a follow-up study  

DOE Green Energy (OSTI)

Impact analyses included in environmental assessments for a selected nuclear power plant, petroleum storage facility, crude oil pipeline, and geopressure well that have experienced operational, abnormal events are compared with the data quantifying the environmental impacts of the events. Comparisons of predicted vs actual impacts suggests that prediction of the types of events and associated impacts could be improved; in some instances, impacts have been underestimated. Analysis of abnormal events is especially important in environmental assessment documents addressing a technology that is novel or unique to a particular area. Incorporation of abnormal event impact analysis into project environmental monitoring and emergency response plans can help improve these plans and can help reduce the magnitude of environmental impacts resulting from said events.

Hunsaker, D.B. Jr.; Lee, D.W.

1985-01-01T23:59:59.000Z

436

Method and system for determining precursors of health abnormalities from processing medical records  

DOE Patents (OSTI)

Medical reports are converted to document vectors in computing apparatus and sampled by applying a maximum variation sampling function including a fitness function to the document vectors to reduce a number of medical records being processed and to increase the diversity of the medical records being processed. Linguistic phrases are extracted from the medical records and converted to s-grams. A Haar wavelet function is applied to the s-grams over the preselected time interval; and the coefficient results of the Haar wavelet function are examined for patterns representing the likelihood of health abnormalities. This confirms certain s-grams as precursors of the health abnormality and a parameter can be calculated in relation to the occurrence of such a health abnormality.

Patton, Robert M; Potok, Thomas E; Beckerman, Barbara G

2013-06-25T23:59:59.000Z

437

V-204: A specially crafted query can cause BIND to terminate abnormally |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

V-204: A specially crafted query can cause BIND to terminate V-204: A specially crafted query can cause BIND to terminate abnormally V-204: A specially crafted query can cause BIND to terminate abnormally July 27, 2013 - 4:35am Addthis PROBLEM: A specially crafted query that includes malformed rdata can cause named to terminate with an assertion failure while rejecting the malformed query. PLATFORM: BIND 9.7 ABSTRACT: A specially crafted query sent to a BIND nameserver can cause it to crash (terminate abnormally). REFERENCE LINKS: ISC Knowledge Base CVE-2013-4854 IMPACT ASSESSMENT: High DISCUSSION: BIND is an implementation of the Domain Name System (DNS) protocols. Authoritative and recursive servers are equally vulnerable. Intentional exploitation of this condition can cause a denial of service in all nameservers running affected versions of BIND 9. Access Control Lists do

438

A Bidirectional, Triple-Voltage DC-DC Converter for Hybrid and Fuel Cell Vehicle Power Systems  

Science Conference Proceedings (OSTI)

Electrical power systems in future hybrid and fuel cell vehicles may employ three voltage (14V, 42V and high voltage (HV)) nets. These will be necessary to accommodate existing 14V loads as well as efficiently handle new heavy loads at the 42V net and an electrical traction drive on the HV bus. A low-cost bi-directional dc-dc converter was proposed in (10) for connecting the three voltage nets. The converter consists of two half-bridges and a high-frequency transformer; thus minimizing the number of switching devices and their associated gate driver components. One salient feature is that the half-bridge on the 42V bus is also utilized to provide the 14V bus by operating its duty ratio around an atypical value of 1/3. This eliminates the need for an additional 14V/42V converter. Moreover, it makes use of the parasitic capacitance of the switches and the transformer leakage inductance for soft-switching; no extra active switches or passive resonant components are required. The use of half-bridges makes the topology suitable for interleaved multi-phase 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 the atypical duty ratio on the transformer and a preferred multi-phase configuration to minimize capacitor ripple currents.

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

2007-01-01T23:59:59.000Z

439

Design of frequency synthesizers for short range wireless transceivers  

E-Print Network (OSTI)

The rapid growth of the market for short-range wireless devices, with standards such as Bluetooth and Wireless LAN (IEEE 802.11) being the most important, has created a need for highly integrated transceivers that target drastic power and area reduction while providing a high level of integration. The radio section of the devices designed to establish communications using these standards is the limiting factor for the power reduction efforts. A key building block in a transceiver is the frequency synthesizer, since it operates at the highest frequency of the system and consumes a very large portion of the total power in the radio. This dissertation presents the basic theory and a design methodology of frequency synthesizers targeted for short-range wireless applications. Three different examples of synthesizers are presented. First a frequency synthesizer integrated in a Bluetooth receiver fabricated in 0.35?m CMOS technology. The receiver uses a low-IF architecture to downconvert the incoming Bluetooth signal to 2MHz. The second synthesizer is integrated within a dual-mode receiver capable of processing signals of the Bluetooth and Wireless LAN (IEEE 802.11b) standards. It is implemented in BiCMOS technology and operates the voltage controlled oscillator at twice the required frequency to generate quadrature signals through a divide-by-two circuit. A phase switching prescaler is featured in the synthesizer. A large capacitance is integrated on-chip using a capacitance multiplier circuit that provides a drastic area reduction while adding a negligible phase noise contribution. The third synthesizer is an extension of the second example. The operation range of the VCO is extended to cover a frequency band from 4.8GHz to 5.85GHz. By doing this, the synthesizer is capable of generating LO signals for Bluetooth and IEEE 802.11a, b and g standards. The quadrature output of the 5 - 6 GHz signal is generated through a first order RC - CR network with an automatic calibration loop. The loop uses a high frequency phase detector to measure the deviation from the 90° separation between the I and Q branches and implements an algorithm to minimize the phase errors between the I and Q branches and their differential counterparts.

Valero Lopez, Ari Yakov

2003-05-01T23:59:59.000Z

440

Power and Energy Measurements Low Frequency  

Science Conference Proceedings (OSTI)

... Power and Energy Measurements, Low-Frequency. Rate our Services. ... Power and Energy Measurements, Low-Frequency (56200C-56202C). ...

2013-06-24T23:59:59.000Z

Note: This page contains sample records for the topic "voltage abnormal frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

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

Science Conference Proceedings (OSTI)

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.

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

2007-01-01T23:59:59.000Z

442

Frequency Dependence in Forecast Skill  

Science Conference Proceedings (OSTI)

A method is proposed to calculate measures of forecast skill for high, medium and low temporal frequency variations in the atmosphere. This method is applied to a series of 128 consecutive 1 to 10-day forecasts produced at NMC with their ...

H. M. van Den Dool; Suranjana Saha

1990-01-01T23:59:59.000Z

443

Frequency agile optical parametric oscillator  

DOE Patents (OSTI)

The frequency agile OPO device converts a fixed wavelength pump laser beam to arbitrary wavelengths within a specified range with pulse to pulse agility, at a rate limited only by the repetition rate of the pump laser. Uses of this invention include Laser radar, LIDAR, active remote sensing of effluents/pollutants, environmental monitoring, antisensor lasers, and spectroscopy.

Velsko, Stephan P. (Livermore, CA)

1998-01-01T23:59:59.000Z

444

Frequency agile optical parametric oscillator  

DOE Patents (OSTI)

The frequency agile OPO device converts a fixed wavelength pump laser beam to arbitrary wavelengths within a specified range with pulse to pulse agility, at a rate limited only by the repetition rate of the pump laser. Uses of this invention include Laser radar, LIDAR, active remote sensing of effluents/pollutants, environmental monitoring, antisensor lasers, and spectroscopy. 14 figs.

Velsko, S.P.

1998-11-24T23:59:59.000Z

445

System and method for floating-substrate passive voltage contrast  

DOE Patents (OSTI)

A passive voltage contrast (PVC) system and method are disclosed for analyzing ICs to locate defects and failure mechanisms. During analysis a device side of a semiconductor die containing the IC is maintained in an electrically-floating condition without any ground electrical connection while a charged particle beam is scanned over the device side. Secondary particle emission from the device side of the IC is detected to form an image of device features, including electrical vias connected to transistor gates or to other structures in the IC. A difference in image contrast allows the defects or failure mechanisms be pinpointed. Varying the scan rate can, in some instances, produce an image reversal to facilitate precisely locating the defects or failure mechanisms in the IC. The system and method are useful for failure analysis of ICs formed on substrates (e.g. bulk semiconductor substrates and SOI substrates) and other types of structures.

Jenkins, Mark W. (Albuquerque, NM); Cole, Jr., Edward I. (Albuquerque, NM); Tangyunyong, Paiboon (Albuquerque, NM); Soden, Jerry M. (Placitas, NM); Walraven, Jeremy A. (Albuquerque, NM); Pimentel, Alejandro A. (Albuquerque, NM)

2009-04-28T23:59:59.000Z

446

High-voltage atmospheric breakdown across intervening rutile dielectrics.  

SciTech Connect

This report documents work conducted in FY13 on electrical discharge experiments performed to develop predictive computational models of the fundamental processes of surface breakdown in the vicinity of high-permittivity material interfaces. Further, experiments were conducted to determine if free carrier electrons could be excited into the conduction band thus lowering the effective breakdown voltage when UV photons (4.66 eV) from a high energy pulsed laser were incident on the rutile sample. This report documents the numerical approach, the experimental setup, and summarizes the data and simulations. Lastly, it describes the path forward and challenges that must be overcome in order to improve future experiments for characterizing the breakdown behavior for rutile.

Williamson, Kenneth Martin; Simpson, Sean; Coats, Rebecca Sue; Jorgenson, Roy Eberhardt; Hjalmarson, Harold Paul; Pasik, Michael Francis

2013-09-01T23:59:59.000Z

447

Monolithic high voltage nonlinear transmission line fabrication process  

DOE Patents (OSTI)

A process for fabricating sequential inductors and varistor diodes of a monolithic, high voltage, nonlinear, transmission line in GaAs is disclosed. An epitaxially grown laminate is produced by applying a low doped active n-type GaAs layer to an n-plus type GaAs substrate. A heavily doped p-type GaAs layer is applied to the active n-type layer and a heavily doped n-type GaAs layer is applied to the p-type layer. Ohmic contacts are applied to the heavily doped n-type layer where diodes are desired. Multiple layers are then either etched away or Oxygen ion implanted to isolate individual varistor diodes. An insulator is applied between the diodes and a conductive/inductive layer is thereafter applied on top of the insulator layer to complete the process. 6 figs.

Cooper, G.A.

1994-10-04T23:59:59.000Z

448

Monolithic high voltage nonlinear transmission line fabrication process  

DOE Patents (OSTI)

A process for fabricating sequential inductors and varactor diodes of a monolithic, high voltage, nonlinear, transmission line in GaAs is disclosed. An epitaxially grown laminate is produced by applying a low doped active n-type GaAs layer to an n-plus type GaAs substrate. A heavily doped p-type GaAs layer is applied to the active n-type layer and a heavily doped n-type GaAs layer is applied to the p-type layer. Ohmic contacts are applied to the heavily doped n-type layer where diodes are desired. Multiple layers are then either etched away or Oxygen ion implanted to isolate individual varactor diodes. An insulator is applied between the diodes and a conductive/inductive layer is thereafter applied on top of the insulator layer to complete the process.

Cooper, Gregory A. (346 Primrose Dr., Pleasant Hill, CA 94523)

1994-01-01T23:59:59.000Z

449

Voltage spike detection in high field superconducting accelerator magnets  

SciTech Connect

A measurement system for the detection of small magnetic flux changes in superconducting magnets, which are due to either mechanical motion of the conductor or flux jump, has been developed at Fermilab. These flux changes are detected as small amplitude, short duration voltage spikes, which are {approx}15mV in magnitude and lasts for {approx}30 {micro}sec. The detection system combines an analog circuit for the signal conditioning of two coil segments and a fast data acquisition system for digitizing the results, performing threshold detection, and storing the resultant data. The design of the spike detection system along with the modeling results and noise analysis will be presented. Data from tests of high field Nb{sub 3}Sn magnets at currents up to {approx}20KA will also be shown.

Orris, D.F.; Carcagno, R.; Feher, S.; Makulski, A.; Pischalnikov, Y.M.; /Fermilab

2004-12-01T23:59:59.000Z

450

Voltage holding considerations for direct-collection units  

SciTech Connect

Results have been obtained from initial experiments designed to study high-voltage breakdown under conditions of importance to the design of direct- collection units. A coaxial configuration was used to mock-up critical fields near grid wires. With appropriate heat conditioning, fields as high as 9.6 x 10/ sup 5/ V/cm were maintained at the surface of a 7-mil-diam tungsten wire. This represents an enhanced field of ~10/sup 8/V/cm at whisker'' sites. Breakdown criteria are proposed for three regimes; initial, field-emission, and ultimate, which differ by the amount of prior conditioning applied to the wire. Additional considerations of importance to direct collectors such as the effect of thermionic emission and ion bombardment are discussed. (auth)

Miley, G.H.

1973-12-01T23:59:59.000Z

451

High voltage design structure for high temperature superconducting device  

DOE Patents (OSTI)

In accordance with the present invention, modular corona shields are employed in a HTS device to reduce the electric field surrounding the HTS device. In a exemplary embodiment a fault current limiter module in the insulation region of a cryogenic cooling system has at least one fault current limiter set which employs a first corona shield disposed along the top portion of the fault current limiter set and is electrically coupled to the fault current limiter set. A second corona shield is disposed along the bottom portion of the fault current limiter set and is electrically coupled to the fault current limiter set. An insulation barrier is disposed within the insulation region along at least one side of the fault current limiter set. The first corona shield and the second corona shield act together to reduce the electric field surrounding the fault limiter set when voltage is applied to the fault limiter set.

Tekletsadik, Kasegn D. (Rexford, NY)

2008-05-20T23:59:59.000Z

452

Curing system for high voltage cross linked cables  

DOE Patents (OSTI)

This invention makes extruded, vulcanized, high voltage cables insulated with thermosetting compounds at much higher rates of production and with superior insulation of reduced thickness and with reduced cavities or voids in the insulation. As the cable comes from an extruder, it passes into a curing chamber with a heat booster that quickly raises the insulation to a temperature at which it is cured much more quickly than with steam heating of the prior art. A high temperature liquid in contact with the insulation maintains the high temperature; and because of the greater curing heat, the cable can travel through the curing chamber at a faster rate and into a cooling tube where it contacts with a cooling liquid under high pressure. The insulation compound is treated to reduce the size of cavities; and the high pressure maintained by the curing and cooling mediums prevent expansion of cavities before the insulation is set.

Bahder, George (Edison, NJ); Katz, Carlos (Edison, NJ); Bopp, Louis A. (Fair Haven, NJ)

1978-01-01T23:59:59.000Z

453

Sacramento Area Voltage Support Draft Environmental Impact Statement  

Science Conference Proceedings (OSTI)

The Western Area Power Administration's Central Valley Project transmission system forms an integral part of the interconnected Sacramento area transmission grid. Western is contractually responsible to oversee that the system is operated in accordance with strict reliability standards. Growth in the greater Sacramento, California area and power imported from generation outside the region, have increased the demand on the interconnected electric transmission system, leading to transmission system overloads and reducing the reliability and security of the area power system. Western has prepared this Sacramento Area Voltage Support (SVS) Draft Environmental Impact Statement (EIS) in compliance with Federal laws, regulations and guidelines, principally the ''National Environmental Policy Act'' (NEPA). This Draft EIS evaluates the potential environmental effects of physical improvements to the area's power system. Enhancements are needed to improve system reliability and provide voltage support for the Sacramento area. The results of public scoping meetings, workshops, meetings with agencies, and earlier studies by Western and area utilities helped to develop a range of alternatives for analysis. The Proposed Action involves: Constructing a new double-circuit, 230-kV transmission line paralleling the existing double-circuit, 230-kV line from the O'Banion Substation to the Elverta Substation; Realigning a portion of the existing Cottonwood-Roseville single-circuit, 230-kV transmission line north of Elverta Substation; and Reconductoring the existing double-circuit, 230-kV transmission line from the Elverta Substation to the Tracy Substation. Public Hearings on the Draft EIS will be held between December 9-12, 2002. Comments on this Draft EIS are encouraged and should be sent to Ms. Loreen McMahon (above). Comments must be received by December 30, 2002.

N /A

2002-11-15T23:59:59.000Z

454

Sacramento Area Voltage Support Final Environmental Impact Statement  

Science Conference Proceedings (OSTI)

The Western Area Power Administration's Central Valley Project transmission system forms an integral part of the interconnected Sacramento area transmission grid. Western is contractually responsible to oversee that the system is operated in accordance with strict reliability standards. Growth in the greater Sacramento, California area and power imported from generation outside the region, have increased the demand on the interconnected electric transmission system, leading to transmission system overloads and reducing the reliability and security of the area power system. Western has prepared this Sacramento Area Voltage Support (SVS) Draft Environmental Impact Statement (EIS) in compliance with Federal laws, regulations and guidelines, principally the National Environmental Policy Act (NEPA). This Draft EIS evaluates the potential environmental effects of physical improvements to the area's power system. Enhancements are needed to improve system reliability and provide voltage support for the Sacramento area. The results of public scoping meetings, workshops, meetings with agencies, and earlier studies by Western and area utilities helped to develop a range of alternatives for analysis. The Proposed Action involves: (1) Constructing a new double-circuit, 230-kV transmission line paralleling the existing double-circuit, 230-kV line from the O'Banion Substation to the Elverta Substation; (2) Realigning a portion of the existing Cottonwood-Roseville single-circuit, 230-kV transmission line north of Elverta Substation; and (3) Reconductoring the existing double-circuit, 230-kV transmission line from the Elverta Substation to the Tracy Substation. Public Hearings on the Draft EIS will be held between December 9-12, 2002. Comments on this Draft EIS are encouraged and should be sent to Ms. Loreen McMahon (above). Comments must be received by December 30, 2002.

N /A

2003-09-19T23:59:59.000Z

455

Abnormal humidity-dependent electrical properties of amorphous carbon/silicon heterojunctions  

Science Conference Proceedings (OSTI)

Amorphous carbon (a-C) film/n-Si heterojunctions have been fabricated by pulse laser deposition, and their current-voltage characteristics have been investigated. The results show that the atmosphere relative humidity (RH) has a significant effect on the reverse bias I-V characteristics of the heterojunctions. For the low bias voltages, the resistance of the a-C/Si heterojunction decreases with the increase of the RH. However, when the applied voltage is greater than a threshold, the resistance of the a-C/Si heterojunctions increases with the increase of the RH. This humidity-dependent phenomenon is attributed to the charge transfer from the absorbed H{sub 2}O molecular to a-C film.

Gao Xili; Zhang Xiaozhong; Wan Caihua; Zhang Xin; Wu Lihua; Tan Xinyu [Department of Materials Science and Engineering, Laboratory of Advanced Materials, Tsinghua University, Beijing 100084 (China) and National Center for Electron Microscopy (Beijing), Tsinghua University, Beijing 100084 (China)

2010-11-22T23:59:59.000Z

456

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

E-Print Network (OSTI)

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

Lemmon, Michael

457

Some Observations on Optimal Frequency Selection in DVFS-based Energy Consumption Minimization  

E-Print Network (OSTI)

In recent years, the issue of energy consumption in parallel and distributed computing systems has attracted a great deal of attention. In response to this, many energy-aware scheduling algorithms have been developed primarily using the dynamic voltage-frequency scaling (DVFS) capability which has been incorporated into recent commodity processors. Majority of these algorithms involve two passes: schedule generation and slack reclamation. The former pass involves the redistribution of tasks among DVFS-enabled processors based on a given cost function that includes makespan and energy consumption; and, while the latter pass is typically achieved by executing individual tasks with slacks at a lower processor frequency. In this paper, a new slack reclamation algorithm is proposed by approaching the energy reduction problem from a different angle. Firstly, the problem of task slack reclamation by using combinations of processors' frequencies is formulated. Secondly, several proofs are provided to show that (1) if...

Rizvandi, Nikzad Babaii; Zomaya, Albert Y

2012-01-01T23:59:59.000Z

458

Turbine-Generator Topics for Power Plant Engineers: Synchronous Generator Voltage Regulator Basics  

Science Conference Proceedings (OSTI)

This material is intended for the new engineer, the control room operator, management, or the non-engineer. The basics of a synchronous generator excitation system; the fundamentals of the voltage regulator; and its controls and functions are discussed. The typical exciter types are covered, but not in detail. There is also basic information on voltage regulator maintenance issues. Put simply, the excitation system is made up of three basic component systems. The voltage regulator monitors the synchronou...

2012-02-16T23:59:59.000Z

459

Assessment and Evaluation of Next Generation High-Voltage DC Technologies—Phase 2  

Science Conference Proceedings (OSTI)

As an established technology for bulk power transmission, high-voltage direct current (HVDC) power transmission is being used worldwide, and more than 100 schemes are operating at present. Advances in voltage sourced converter (VSC) technologies and power electronic devices with use of insulated-gate bipolar transistors (IGBTs) will provide improved system performance and reliability. Also, the present highest operating voltage is +/- 800 kV as China and India are building +/- 800-kV lines. Anticipating ...

2009-12-17T23:59:59.000Z

460

Technology Assessment and Application Guide for a Capacitor-Based Voltage Sag Compensator  

Science Conference Proceedings (OSTI)

Voltage sags and momentary interruptions result in a significant amount of process shutdowns for industrial customers. Voltage sag compensation devices help mitigate sags for susceptible devices and components, allowing for more reliable and robust process performance. This report provides a technology assessment and application guide for Marathon Power's Voltage Sag Compensator, a 120-V, 750-VA unit designed to provide AC backup power to sensitive electronic loads.

2009-12-22T23:59:59.000Z

Note: This page contains sample records for the topic "voltage abnormal frequency" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

ETTM: Low Voltage System Protection and Coordination Computer-Based Training Version 1.0  

Science Conference Proceedings (OSTI)

ETTM Low Voltage System Protection and Coordination is a computer-based training module that allows users to access training when desired and review it at their own pace. It provides graphics and limited interactive features to enhance learning. Low voltage power systems are generally classified as AC power systems operating at the 120 600 Volt level. Because they often serve a large number of diverse loads in residences, businesses, and power plants, low voltage power systems present a unique set of cha...

2010-11-30T23:59:59.000Z

462

Combining multiple classifiers to quantitatively rank the impact of abnormalities in flight data  

Science Conference Proceedings (OSTI)

This paper presents a novel two phase method that combines one class support vector machine classifiers using combination rules to quantitatively assess the degree of abnormality at various heights during individual aircraft descents and also over the ... Keywords: Aircraft landing guidance, Artificial intelligence, Fault diagnosis, Support vector machines

E. Smart; D. Brown; J. Denman

2012-08-01T23:59:59.000Z

463

Development and experimental validation of computational methods to simulate abnormal thermal and structural environments  

Science Conference Proceedings (OSTI)

Over the past 40 years, Sandia National Laboratories (SNL) has been actively engaged in research to improve the ability to accurately predict the response of engineered systems to abnormal thermal and structural environments. These engineered systems contain very hazardous materials. Assessing the degree of safety/risk afforded the public and environment by these engineered systems, therefore, is of upmost importance. The ability to accurately predict the response of these systems to accidents (to abnormal environments) is required to assess the degree of safety. Before the effect of the abnormal environment on these systems can be determined, it is necessary to ascertain the nature of the environment. Ascertaining the nature of the environment, in turn, requires the ability to physically characterize and numerically simulate the abnormal environment. Historically, SNL has demonstrated the level of safety provided by these engineered systems by either of two approaches: (1) a purely regulatory approach, or (2) by a Probabilistic Risk Assessment (PRA). This paper will address the latter of the two approaches.

Moya, J.L.; Skocypec, R.D.; Thomas, R.K.

1993-10-01T23:59:59.000Z

464

eDoctor: Automatically Diagnosing Abnormal Battery Drain Issues on Smartphones  

E-Print Network (OSTI)

under typical usage, but at some point the battery unexpectedly started to drain faster than usual usage of the device or a particular app. An energy profiler can give the battery usage of each app phase share similar resource usage patterns. When an app starts to consume energy in an abnormal way

Fainman, Yeshaiahu

465

A Re nery Immobot for Abnormal Situation Management Kurt D. Krebsbach and David J. Musliner  

E-Print Network (OSTI)

be extremely costly,resulting in poor product qual- ity, schedule delays, equipment damage, reduced occu represents an extreme case within the spec- trum of major industrial process disruptions, collec- tively, estimating (abnormal) states, and diagnosing, isolating, and recovering from mal- functions. At the Honeywell

Krebsbach, Kurt D.

466

Automated Heart Wall Motion Abnormality Detection From Ultrasound Images using Bayesian Networks  

E-Print Network (OSTI)

Automated Heart Wall Motion Abnormality Detection From Ultrasound Images using Bayesian Networks± . maleeha.qazi@siemens.com , glenn.fung@siemens.com Abstract Coronary Heart Disease can be diagnosed by mea- suring and scoring regional motion of the heart wall in ultrasound images of the left ventricle (LV

Rosales, Rómer E.

467

Radio Frequency Identification Tags - Active Tags ...  

Selectable, license free, RF frequency bands; Ultra low power sleep mode; Miniaturized, encapsulated bendable packaging;

468

Analysis and design of high frequency link power conversion systems for fuel cell power conditioning  

E-Print Network (OSTI)

In this dissertation, new high frequency link power conversion systems for the fuel cell power conditioning are proposed to improve the performance and optimize the cost, size, and weight of the power conversion systems. The first study proposes a new soft switching technique for the phase-shift controlled bi-directional dc-dc converter. The described dc-dc converter employs a low profile high frequency transformer and two active full-bridge converters for bidirectional power flow capability. The proposed new soft switching technique guarantees soft switching over wide range from no load to full load without any additional circuit components. The load range for proposed soft switching technique is analyzed by mathematical approach with equivalent circuits and verified by experiments. The second study describes a boost converter cascaded high frequency link direct dc-ac converter suitable for fuel cell power sources. A new multi-loop control for a boost converter to reduce the low frequency input current harmonics drawn from the fuel cell is proposed, and a new PWM technique for the cycloconverter at the secondary to reject the low order harmonics in the output voltages is presented. The performance of the proposed scheme is verified by the various simulations and experiments, and their trade-offs are described in detail using mathematical evaluation approach. The third study proposes a current-fed high frequency link direct dc-ac converter suitable for residential fuel cell power systems. The high frequency full-bridge inverter at the primary generates sinusoidally PWM modulated current pulses with zero current switching (ZCS), and the cycloconverter at the secondary which consists of only two bidirectional switches and output filter capacitors produces sinusoidally modulated 60Hz split single phase output voltage waveforms with near zero current switching. The active harmonic filter connected to the input terminal compensates the low order input current harmonics drawn from the fuel cell without long-term energy storage devices such as batteries and super capacitors.

Song, Yu Jin

2004-08-01T23:59:59.000Z

469

Unlikely Combination of Experiments with a Novel High-Voltage CIGS Photovoltaic Array (Presentation)  

DOE Green Energy (OSTI)

The goals of this study are to: (1) parameterize current-voltage (I-V) performance over a wide range of illumination and temperatures: (a) 50-1150 W/m{sup 2} irradiance, 5-65 C; (b) obtain array temperature coefficients; and (c) quantify energy production; (2) investigate high-voltage leakage currents from the CIS modules in a high-voltage array: determine dependence on moisture, temperature, and voltage bias and ascertain corrosion problems if any; and (3) study long-term power and energy production stability.

del Cueto, J. A.; Sekulic, B. R.

2006-05-01T23:59:59.000Z

470

Phase-Field Simulations of a Simple Voltage-Controlled Magnetic ...  

Science Conference Proceedings (OSTI)

The voltage-induced magnetization and/or magnetic domain switching dynamics in ... Our results offer a promising new way towards future high-performance ...

471

Effect of Voltage Pulse Duration on Surface Properties of Micro Arc ...  

Science Conference Proceedings (OSTI)

Durations of successive positive and negative voltage pulses in one cycle ... Electrodeposition of Ni-Al-Cr Bond Coat and Its High Temperature Behavior on ...

472

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

DOE Green Energy (OSTI)

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

Murty, Balarama Vempaty (West Bloomfield, MI)

2000-01-01T23:59:59.000Z

473

Summary of transient high-voltage calculations for the FRX-C experiment  

Science Conference Proceedings (OSTI)

Calculations of the electrical circuit equations are performed over a wide range of parameters corresponding to the FRX-C field-reversed THETA-pinch experiment at Los Alamos. Without any plasma or external damping, serious voltage doubling and quadrupling of the main capacitor bank charge voltage are observed. These oscillating high voltages are found to be adequately suppressed by the strategic placement of external snubber circuitry. On the other hand, no doubling of the THETA-pinch preionization bank charge voltage is found. Calculations of the equations for the z-pinch preionization circuit are also performed.

Kewish, R.W. Jr.; Rej, D.J.

1982-06-01T23:59:59.000Z

474

The dynamics of electricity demand and supply in the low voltage distribution grid: a model study:.  

E-Print Network (OSTI)

??In this thesis a simulation study is executed that analyses how new developments of household electricity demand and decentralised electricity generation affect the low voltage… (more)

Van Zoest, P.L.A.

2013-01-01T23:59:59.000Z

475

Measurement-based Voltage Stability Margin Calculator (MVSMC) v1.0  

Science Conference Proceedings (OSTI)

Voltage stability is a major concern in daily power system operations and a leading factor to limit power transfers in a prevailing open access environment. Voltage instability usually starts from a local bus or area, and then may evolve into a wide-area instability problem if it cannot be controlled locally. This program utilizes EPRImeasurement-based voltage stability monitoring technology and is able to calculate voltage stability margin indices at a load bus or for an entire load area using the measu...

2009-10-30T23:59:59.000Z

476

Triple-Voltage DC-DC Converter - Oak Ridge National Laboratory  

Overall Project Objective ... –Saving in the switch and gate drive component count increases ... power transfer between the low-voltage buses and the high

477

Test results of the AGS Booster low frequency RF system  

Science Conference Proceedings (OSTI)

The Band II RF system was originally built to support the Booster operations during the acceleration of heavy ions. Designed to sweep from 0.6 to 2.5 MHz, it was build and successfully tested over a much broader range reaching 4 MHz. Voltages up to more than 20 kV were reached over the design frequency range. The system consists of two stations, each of which is made of one single gap cavity directly driven by a grounded cathode push pull power amplifier. The low Q high permeability ferrites needed in the coaxial cavity in order to reach the lower end of the band make tuning extremely easy. Both systems were thoroughly tested both at single frequencies and on a sweep and are now installed in the ring, ready for operations. Static measurements showed no high-loss effects. The Band 11 system has been fully described in a previous paper; presented here are the results of the ``bench`` tests that lead to important performance improvements.

Sanders, R.T.; Cameron, P.; Damm, R.; Dunbar, A.; Goldman, M.; Kasha, D.; McNerney, A.; Meth, M.; Ratti, A.; Spitz, R.

1993-06-01T23:59:59.000Z

478

Radio frequency coaxial feedthrough device  

DOE Patents (OSTI)

A radio frequency coaxial vacuum feedthrough is provided which utilizes a cylindrical ceramic vacuum break formed of an alumina ceramic. The cylinder is coaxially disposed and brazed between tapered coaxial conductors to form a vacuum sealed connection between a pressurized upstream coaxial transmission line and a utilization device located within a vacuum container. The feedthrough provides 50 ohm matched impedance RF feedthrough up to about 500 MHz at power levels in the multimegawatt range.

Owens, Thomas L. (Kingston, TN); Baity, Frederick W. (Oak Ridge, TN); Hoffman, Daniel J. (Oak Ridge, TN); Whealton, John H. (Oak Ridge, TN)

1987-01-01T23:59:59.000Z

479

H{sup -} beam extraction from a cesium seeded field effect transistor based radio frequency negative hydrogen ion source  

SciTech Connect

H{sup -} beam was successfully extracted from a cesium seeded ion source operated using a field effect transistor inverter power supply as a radio frequency (RF) wave source. High density hydrogen plasma more than 10{sup 19} m{sup -3} was obtained using an external type antenna with RF frequency of lower than 0.5 MHz. The source was isolated by an isolation transformer and H{sup -} ion beam was extracted from a single aperture. Acceleration current and extraction current increased with the increase of extraction voltage. Addition of a small amount of cesium vapor into the source enhanced the currents.

Ando, A.; Matsuno, T.; Funaoi, T.; Tanaka, N. [School of Engineering, Tohoku University, Sendai 980-8579 (Japan); Tsumori, K.; Takeiri, Y. [National Institute for Fusion Science, Toki 509-5292 (Japan)

2012-02-15T23:59:59.000Z

480

Tailoring electron energy distribution functions through energy confinement in dual radio-frequency driven atmospheric pressure plasmas  

SciTech Connect

A multi-scale numerical model based on hydrodynamic equations with semi-kinetic treatment of electrons is used to investigate the influence of dual frequency excitation on the effective electron energy distribution function (EEDF) in a radio-frequency driven atmospheric pressure plasma. It is found that variations of power density, voltage ratio, and phase relationship provide separate control over the electron density and the mean electron energy. This is exploited to directly influence both the phase dependent and time averaged effective EEDF. This enables tailoring the EEDF for enhanced control of non-equilibrium plasma chemical kinetics at ambient pressure and temperature.

O'Neill, C.; Waskoenig, J. [Centre for Plasma Physics, School of Maths and Physics, Queen's University Belfast, Belfast BT7 1NN (United Kingdom); Gans, T. [Centre for Plasma Physics, School of Maths and Physics, Queen's University Belfast, Belfast BT7 1NN (United Kingdom); York Plasma Institute, Department of Physics, University of York, York YO10 5DD (United Kingdom)

2012-10-08T23:59:59.000Z

Note: This page contains sample records for the topic "voltage abnormal frequency" from the National Library of EnergyBeta (NLEBeta).
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481

High voltage power supply with modular series resonant inverters  

DOE Patents (OSTI)

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

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

1995-01-01T23:59:59.000Z

482

High voltage power supply with modular series resonant inverters  

DOE Patents (OSTI)

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

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

1995-07-18T23:59:59.000Z

483

Life testing of a low voltage air circuit breaker  

Science Conference Proceedings (OSTI)

A DS-416 low voltage air circuit breaker manufactured by Westinghouse was mechanically cycled to identify age-related degradation in the various breaker subcomponents, specifically the power-operated mechanism. This accelerated aging test was performed on one breaker unit for over 36,000 cycles. Three separate pole shafts, one with a 60-degree weld, one with a 120-degree weld, and one with a 180-degree weld in the third pole lever were used to characterize cracking in the welds. In addition, during the testing three different operating mechanisms and several other parts were replaced as they became inoperable. Among the seven welds on the pole shaft, {number_sign}1 and {number_sign}3 were found to be critical ones whose fracture can result in misalignment of the pole levers. This can lead to problems with the operating mechanism, including the burning of coils, excessive wear in certain parts, and overstressed linkages. Furthermore, the limiting service life of a number of subcomponents of the power-operated mechanism, including the operating mechanism itself, were assessed. Based on these findings, suggestions are provided to alleviate the age-related degradation that could occur as a result of normal closing and opening of the breaker contacts during its service life. Also, cause and effect analyses of various age-related degradation in various breaker parts are discussed.

Subudhi, M. [Brookhaven National Lab., Upton, NY (United States); Aggarwal, S. [Nuclear Regulatory Commission, Washington, DC (United States)

1992-06-01T23:59:59.000Z

484

Life testing of a low voltage air circuit breaker  

Science Conference Proceedings (OSTI)

A DS-416 low voltage air circuit breaker manufactured by Westinghouse was mechanically cycled to identify age-related degradation in the various breaker subcomponents, specifically the power-operated mechanism. This accelerated aging test was performed on one breaker unit for over 36,000 cycles. Three separate pole shafts, one with a 60-degree weld, one with a 120-degree weld, and one with a 180-degree weld in the third pole lever were used to characterize cracking in the welds. In addition, during the testing three different operating mechanisms and several other parts were replaced as they became inoperable. Among the seven welds on the pole shaft, {number sign}1 and {number sign}3 were found to be critical ones whose fracture can result in misalignment of the pole levers. This can lead to problems with the operating mechanism, including the burning of coils, excessive wear in certain parts, and overstressed linkages. Furthermore, the limiting service life of a number of subcomponents of the power-operated mechanism, including the operating mechanism itself, were assessed. Based on these findings, suggestions are provided to alleviate the age-related degradation that could occur as a result of normal closing and opening of the breaker contacts during its service life. Also, cause and effect analyses of various age-related degradation in various breaker parts are discussed.

Subudhi, M. (Brookhaven National Lab., Upton, NY (United States)); Aggarwal, S. (Nuclear Regulatory Commission, Washington, DC (United States))

1992-01-01T23:59:59.000Z

485

PRESENT AND FUTURE TECHNOLOGY OF HIGH VOLTAGE SYSTEMS FOR NEUTRAL BEAM INJECTORS  

E-Print Network (OSTI)

the accel voltage reg­ ulation requirement could be relaxedVOLTAGE SWITCHES TUBES SCR ASSEMBLIES CROSSED-FIELD INTERRUPTERS MAGNETIC CORE ARC SNUEBER3 COMPUTERS FOR CONTROL AND DIAGNOSTICS OPERATIONAL REQUIREMENTSvoltage- regulated (flat-topped) to 1%. If good regulation Is not a prime requirement,

Baker, W.R.

2011-01-01T23:59:59.000Z

486

Voltage-tunable singlet-triplet transition in lateral quantum dots  

E-Print Network (OSTI)

Results of calculations and high source-drain transport measurements are presented which demonstrate voltage-tunable entanglement of electron pairs in lateral quantum dots. At