Sample records for voltage abnormal frequency

  1. Abnormalities of chromatic and luminance critical flicker frequency in

    E-Print Network [OSTI]

    Foster, David H.

    Abnormalities of chromatic and luminance critical flicker frequency in multiple sclerosis Robert J*** Criticalflickerfrequency (CFF) was measuredfor stimuli varying in chromaticity only and in luminance onlyfor patients underlying linear interdependencies for the two groups, consistent with a greater loss of temporal luminance

  2. Coordination of Voltage and Frequency Feedback in Load-Frequency Control Capability of Wind Turbine

    E-Print Network [OSTI]

    Silva, Filipe Faria Da

    Coordination of Voltage and Frequency Feedback in Load-Frequency Control Capability of Wind Turbine-Frequency Control (LFC) is gradually shifted to Variable Speed Wind Turbines (VSWTs). In order to equip VSWT

  3. High frequency AC power converter for low voltage circuits

    E-Print Network [OSTI]

    Salazar, Nathaniel Jay Tobias

    2012-01-01T23:59:59.000Z

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

  4. SiGe BiCMOS Topologies for Low-Voltage Millimeter-Wave Voltage Controlled Oscillators and Frequency Dividers

    E-Print Network [OSTI]

    Voinigescu, Sorin Petre

    SiGe BiCMOS Topologies for Low-Voltage Millimeter-Wave Voltage Controlled Oscillators and Frequency-mail: tod@eecg.toronto.edu Abstract -- BiCMOS topologies for mm-wave voltage- controlled oscillators operation for mm-wave applications. II. BICMOS VOLTAGE-CONTROLLED OSCILLATOR The Colpitts topology

  5. Memory Power Management via Dynamic Voltage/Frequency Scaling

    E-Print Network [OSTI]

    McGaughey, Alan

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

  6. Memory Power Management via Dynamic Voltage/Frequency Scaling

    E-Print Network [OSTI]

    Mutlu, Onur

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

  7. Understanding Pound-Drever-Hall locking using voltage controlled radio-frequency oscillators: An undergraduate experiment

    E-Print Network [OSTI]

    Le Roy, Robert J.

    Understanding Pound-Drever-Hall locking using voltage controlled radio-frequency oscillators. The three main pieces of equipment are a commercial voltage controlled oscillator, a resonating cavity of the voltage controlled oscillator. The cavity resonance is then observed by scanning the frequency

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

    DOE Patents [OSTI]

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

    2011-03-22T23:59:59.000Z

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

  9. CONCEPT OF FREQUENCY-TRANSCONDUCTANCE TUNING OF BIPOLAR VOLTAGE-CONTROLLED OSCILLATORS

    E-Print Network [OSTI]

    Serdijn, Wouter A.

    CONCEPT OF FREQUENCY-TRANSCONDUCTANCE TUNING OF BIPOLAR VOLTAGE-CONTROLLED OSCILLATORS Aleksandar-transconductance tuning, introduced in this paper, offers the possibility for voltage-controlled oscillators to trade-tank, the loop-gain, the voltage swing and the phase-noise of the oscillator are changed as well

  10. Voltage stability of the Puget Sound system under abnormally cold weather conditions

    SciTech Connect (OSTI)

    Jimma, K.M.; Sheehan, M.T. (Puget Sound Power and Light, Bellevue, WA (United States)); Comegys, G.L. (Bonneville Power Administration, Portland, OR (United States)); Miller, N.W.; D'Aquila, R.

    1993-08-01T23:59:59.000Z

    The potential for voltage collapse in the Puget Sound area is analyzed. Shunt and series compensation schemes, as well as undervoltage load shedding, are evaluated. Twenty-five minute time simulations of the Puget Sound area system are presented, showing interaction of load dynamics with LTCs, switched compensation and protective equipment. Results and analysis are relevant to utilities worldwide which must address similar concerns.

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

    E-Print Network [OSTI]

    Silva, Filipe Faria Da

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

  12. Current mode integrators and their applications in low-voltage high frequency CMOS signal processing

    E-Print Network [OSTI]

    1993-01-01T23:59:59.000Z

    Low voltage CMOS fully differential integrators for high frequency continuous-time filters using current-mode techniques are presented.. Current mode techniques are employed to avoid the use of the floating differential pair, in order to achieve...

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

    E-Print Network [OSTI]

    Fujimoto, Hiroshi

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

  14. >300GHz Fixed-Frequency and Voltage-Controlled Fundamental Oscillators in an InP DHBT Process

    E-Print Network [OSTI]

    Rodwell, Mark J. W.

    >300GHz Fixed-Frequency and Voltage-Controlled Fundamental Oscillators in an InP DHBT Process, 93106, USA Abstract -- We report fundamental fixed-frequency and voltage-controlled oscillators bandwidth. Index Terms -- Millimeter-wave oscillators, voltage-controlled oscillators, MMIC oscillators. I

  15. Spin-torque diode radio-frequency detector with voltage tuned resonance

    SciTech Connect (OSTI)

    Skowro?ski, Witold, E-mail: skowron@agh.edu.pl; Frankowski, Marek; Stobiecki, Tomasz [AGH University of Science and Technology, Department of Electronics, Al. Mickiewicza 30, 30-059 Krakw (Poland); Wrona, Jerzy [AGH University of Science and Technology, Department of Electronics, Al. Mickiewicza 30, 30-059 Krakw (Poland); Singulus Technologies, Kahl am Main 63796 (Germany); Ogrodnik, Piotr [Faculty of Physics, Warsaw University of Technology, ul. Koszykowa 75, 00-662 Warsaw (Poland); AGH University of Science and Technology, Department of Electronics, Al. Mickiewicza 30, 30-059 Krakw (Poland); Barna?, Jzef [Faculty of Physics, Adam Mickiewicz University, ul. Umultowska 85, 61-614 Pozna? (Poland); Institute of Molecular Physics, Polish Academy of Sciences, Smoluchowskiego 17, 60-179 Pozna? (Poland)

    2014-08-18T23:59:59.000Z

    We report on a voltage-tunable radio-frequency (RF) detector based on a magnetic tunnel junction (MTJ). The spin-torque diode effect is used to excite and/or detect RF oscillations in the magnetic free layer of the MTJ. In order to reduce the overall in-plane magnetic anisotropy of the free layer, we take advantage of the perpendicular magnetic anisotropy at the interface between ferromagnetic and insulating layers. The applied bias voltage is shown to have a significant influence on the magnetic anisotropy, and thus on the resonance frequency of the device. This influence also depends on the voltage polarity. The obtained results are accounted for in terms of the interplay of spin-transfer-torque and voltage-controlled magnetic anisotropy effects.

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

    E-Print Network [OSTI]

    Fujimoto, Hiroshi

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

  17. Optimizing performance per watt on GPUs in High Performance Computing: temperature, frequency and voltage effects

    E-Print Network [OSTI]

    Price, D C; Barsdell, B R; Babich, R; Greenhill, L J

    2014-01-01T23:59:59.000Z

    The magnitude of the real-time digital signal processing challenge attached to large radio astronomical antenna arrays motivates use of high performance computing (HPC) systems. The need for high power efficiency (performance per watt) at remote observatory sites parallels that in HPC broadly, where efficiency is an emerging critical metric. We investigate how the performance per watt of graphics processing units (GPUs) is affected by temperature, core clock frequency and voltage. Our results highlight how the underlying physical processes that govern transistor operation affect power efficiency. In particular, we show experimentally that GPU power consumption grows non-linearly with both temperature and supply voltage, as predicted by physical transistor models. We show lowering GPU supply voltage and increasing clock frequency while maintaining a low die temperature increases the power efficiency of an NVIDIA K20 GPU by up to 37-48% over default settings when running xGPU, a compute-bound code used in radio...

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

    E-Print Network [OSTI]

    Lemmon, Michael

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

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

    E-Print Network [OSTI]

    Qiu, Qinru

    University, State University of New York Binghamton, New York 13902, USA {sliu5, qqiu, qwu problem and prolong the system operating duration, a new technology called energy harvesting, also knownEnergy Aware Dynamic Voltage and Frequency Selection for Real-Time Systems with Energy Harvesting

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

    E-Print Network [OSTI]

    Lemmon, Michael

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

  1. PEV-Based Combined Frequency and Voltage Regulation for Smart Grid

    E-Print Network [OSTI]

    Huang, Jianwei

    by either adjusting supply or changing demand. While various demand side management programs have used benefit both users and utilities. Index Terms--Smart grid, plug-in electric vehicles, demand side management, reactive power compensation, ancillary ser- vices, frequency regulation, voltage regulation

  2. Plug-and-play voltage and frequency control of islanded microgrids with meshed topology

    E-Print Network [OSTI]

    Ferrari-Trecate, Giancarlo

    generation since, differently from common diesel generators, power is produced and delivered to the main grid Generation Units (DGUs). Local controllers regulate voltage and frequency at the Point of Common Coupling Distributed Generation Units (DGUs) designed to operate safely and reliably in absence of a connection

  3. Understanding Pound-Drever-Hall locking using voltage controlled radio-frequency oscillators: An undergraduate experiment

    E-Print Network [OSTI]

    Liekhus-Schmaltz, C E

    2011-01-01T23:59:59.000Z

    A senior undergraduate experiment has been developed for learning about frequency stabilization techniques using radio-frequency electronics. The primary objective is to frequency stabilize a voltage controlled oscillator to a cavity resonance at 800 MHz using the Pound-Drever-Hall scheme. This technique is commonly applied to stabilize lasers at optical frequencies, but by using radio-frequency equipment exclusively it is possible to systematically study various aspects of the technique more thoroughly, inexpensively, and free from eye hazards. Students also learn about modular radio-frequency electronics and basic feedback control loops. By varying the temperature of the resonator, the students may determine the thermal expansion coefficients of copper, aluminum, and super invar.

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

    E-Print Network [OSTI]

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

    2011-10-18T23:59:59.000Z

    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.

  5. Abnormal electron-heating mode and formation of secondary-energetic electrons in pulsed microwave-frequency atmospheric microplasmas

    SciTech Connect (OSTI)

    Kwon, H. C. [Department of Electrical Engineering, Pohang University of Science and Technology, Pohang 790-784 (Korea, Republic of) [Department of Electrical Engineering, Pohang University of Science and Technology, Pohang 790-784 (Korea, Republic of); Research and Development Division, SK Hynix Semiconductor Inc., Icheon 467-701 (Korea, Republic of); Jung, S. Y. [Department of Chemistry and Nano Science, Ewha Womans University, Seoul 120-750 (Korea, Republic of)] [Department of Chemistry and Nano Science, Ewha Womans University, Seoul 120-750 (Korea, Republic of); Kim, H. Y.; Won, I. H.; Lee, J. K., E-mail: jkl@postech.ac.kr [Department of Electrical Engineering, Pohang University of Science and Technology, Pohang 790-784 (Korea, Republic of)

    2014-03-15T23:59:59.000Z

    The formation of secondary energetic electrons induced by an abnormal electron-heating mode in pulsed microwave-frequency atmospheric microplasmas was investigated using particle-in-cell simulation. We found that additional high electron heating only occurs during the first period of the ignition phase after the start of a second pulse at sub-millimeter dimensions. During this period, the electrons are unable to follow the abruptly retreating sheath through diffusion alone. Thus, a self-consistent electric field is induced to drive the electrons toward the electrode. These behaviors result in an abnormal electron-heating mode that produces high-energy electrons at the electrode with energies greater than 50?eV.

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

    E-Print Network [OSTI]

    Ellingson, Steven W.

    -current (HVAC) transmission lines; high-voltage direct-current (HVDC) transmission lines will be addressed

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

    DOE Patents [OSTI]

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

    1994-01-01T23:59:59.000Z

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

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

    DOE Patents [OSTI]

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

    1994-06-28T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

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

    2014-02-12T23:59:59.000Z

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

  10. Control of plasma process by use of harmonic frequency components of voltage and current

    DOE Patents [OSTI]

    Miller, Paul A. (Albuquerque, NM); Kamon, Mattan (Cambridge, MA)

    1994-01-01T23:59:59.000Z

    The present invention provides for a technique for taking advantage of the intrinsic electrical non-linearity of processing plasmas to add additional control variables that affect process performance. The technique provides for the adjustment of the electrical coupling circuitry, as well as the electrical excitation level, in response to measurements of the reactor voltage and current and to use that capability to modify the plasma characteristics to obtain the desired performance.

  11. A High-Frequency Resonant Inverter Topology With Low-Voltage Stress

    E-Print Network [OSTI]

    Rivas, Juan M.

    This paper presents a new switched-mode resonant inverter, which we term the inverter, that is well suited to operation at very high frequencies and to rapid on/off control. Features of this inverter topology include low ...

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

    SciTech Connect (OSTI)

    Garrison, Sean

    2009-05-21T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    Hammerton, James

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

  14. Voltage Control Technical Conference

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

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

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

    SciTech Connect (OSTI)

    None

    2012-01-23T23:59:59.000Z

    GENI Project: GE is developing electricity transmission hardware that could connect distributed renewable energy sources, like wind farms, directly to the grideliminating 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 grids network of transmission lines. Power companies do this because less electricity is lost along the lines when the voltage is high.

  16. Optical voltage reference

    DOE Patents [OSTI]

    Rankin, R.; Kotter, D.

    1994-04-26T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Serdijn, Wouter A.

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

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

    E-Print Network [OSTI]

    Garrison, Sean Michael

    2009-05-22T23:59:59.000Z

    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...

  19. Observation of Optical Solitons and Abnormal Modulation Instability in Liquid Crystals with Negative Dielectric Anisotropy

    E-Print Network [OSTI]

    Wang, Jing; Chen, Junzhu; Liu, Jinlong; Wang, Zhuo; Li, Yiheng; Guo, Qi; Hu, Wei; Xuan, Li

    2015-01-01T23:59:59.000Z

    We investigate theoretically and experimentally the optical beam propagation in the nematic liquid crystal with negative dielectric anisotropy, which is aligned homeotropically in a $80\\mu m$-thickness planar cell in the presence of an externally voltage. It is predicted that the nonlocal nonlinearity of liquid crystal undergo an oscillatory response function with a negative nonlinear refractive index coefficient. We found that the oscillatory nonlocal nonlinearity can support stable bright solitons, which are observed in experiment. We also found that abnormal modulation instability occurs with infinity gain coefficient at a fixed spatial frequency, which is no depend on the beam intensity. We observed the modulation instability in the liquid crystal at a very low intensity ($0.26W/cm^2$), and the maximum gain frequency were found kept unchange when beam power changes over 2-3 orders of magnitude.

  20. Parameter Variation Analysis for Voltage Controlled Oscillators in Phase-Locked Loops

    E-Print Network [OSTI]

    Moon, Un-Ku

    Parameter Variation Analysis for Voltage Controlled Oscillators in Phase-Locked Loops Igor Vytyaz), the oscillation frequency of a voltage-controlled oscillator (VCO) is specified by the reference frequency on the oscillation frequency as the PLL adjusts the control voltage to keep the frequency unchanged. More importantly

  1. the problem by speeding up a workload with parallel pro-cessing at a lower clock frequency (and lower voltage). But

    E-Print Network [OSTI]

    Cho, Sangyeun

    6 , 2 0 0 8 M I C R O P R O C E S S O R R E P O R T REPORT M I C R O P R O C E S S O R T H E I N S I D E R ' S G U I D E T O M I C R O P R O C E S S O R H A R D WA R E www.MPRonline.com #12;between 2 and frequency.2 This article is based on our paper, "Corollaries to Amdahl's Law for Energy,"3 from IEEE

  2. Morphological Abnormalities in Amphibians in Agricultural Habitats: A Case Study of the Common Frog Rana temporaria

    E-Print Network [OSTI]

    Meril, Juha

    background deformity frequency of 05%. Many chemical contaminants, including agrochemicals, can cause along an agrochemical gradient. Abnormalities occurred in a low frequency (1% of the studied individuals abnormality frequencies in the habitats most likely exposed to agrochemicals. Hence, the data suggest

  3. auxiliary voltage converter: Topics by E-print Network

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

    Voltage Switching inverter working at 20 kHz and an output stage (high frequency transformers, Schottky rectifi ers and output filter... Jrgensen, H E; Dupaquier, A;...

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

    SciTech Connect (OSTI)

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

    2013-09-01T23:59:59.000Z

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

  5. High Voltage Safety Act

    Broader source: Energy.gov [DOE]

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

  6. Automatic voltage imbalance detector

    DOE Patents [OSTI]

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

    1984-01-01T23:59:59.000Z

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

  7. Voltage verification unit

    DOE Patents [OSTI]

    Martin, Edward J. (Virginia Beach, VA)

    2008-01-15T23:59:59.000Z

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

  8. Stability issues in IC Low Drop Out voltage regulators

    E-Print Network [OSTI]

    Chava, Krishna Chaitanya

    2002-01-01T23:59:59.000Z

    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...

  9. Strongly nonlinear dynamics of electrolytes in large ac voltages

    E-Print Network [OSTI]

    Hojgaard Olesen, Laurits

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

  10. Integrated, Low Voltage, DynamicallyIntegrated, Low Voltage, Dynamically Adaptive BuckAdaptive Buck--Boost ConverterBoost Converter

    E-Print Network [OSTI]

    Rincon-Mora, Gabriel A.

    Improvement in battery life Low voltage Single cell operation (Li-ion/NiCd/NiMH/Fuel Cell) Integrated frequency 1 MHz 20% Closed-loop bandwidth 50 kHz 1-dB step change response time 20 sec Full-load efficiency 90 % Control signal Output voltageTpower_change Tresponse Time 1 dB Typical transient response

  11. Voltage balanced multilevel voltage source converter system

    DOE Patents [OSTI]

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

    1997-07-01T23:59:59.000Z

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

  12. High voltage DC power supply

    DOE Patents [OSTI]

    Droege, Thomas F. (Batavia, IL)

    1989-01-01T23:59:59.000Z

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

  13. High voltage DC power supply

    DOE Patents [OSTI]

    Droege, T.F.

    1989-12-19T23:59:59.000Z

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

  14. This paper presents a floating slider mechanism to achieve large scanning angular displacements with low voltage

    E-Print Network [OSTI]

    's natural frequency. After a 49% hydrofluoric acid and carbon dioxide LOW -VOLTAGE LARGE ANGULAR: Dual bimorph electrostatic actuator with floating sliders. #12;super-critical point release

  15. ABBGroup-1-High voltage lab

    E-Print Network [OSTI]

    Basse, Nils Plesner

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

  16. Electron launching voltage monitor

    DOE Patents [OSTI]

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

    1992-03-17T23:59:59.000Z

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

  17. Threshold voltage extraction circuit

    E-Print Network [OSTI]

    Hoon, Siew Kuok

    2000-01-01T23:59:59.000Z

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

  18. E-beam high voltage switching power supply

    DOE Patents [OSTI]

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

    1996-10-15T23:59:59.000Z

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

  19. E-beam high voltage switching power supply

    DOE Patents [OSTI]

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

    1996-01-01T23:59:59.000Z

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

  20. High voltage pulse conditioning

    DOE Patents [OSTI]

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

    1990-01-01T23:59:59.000Z

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

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

    DOE Patents [OSTI]

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

    1995-05-23T23:59:59.000Z

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

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

    DOE Patents [OSTI]

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

    1995-01-01T23:59:59.000Z

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

  3. Charge-pump voltage converter

    DOE Patents [OSTI]

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

    2009-11-03T23:59:59.000Z

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

  4. INTEGRATED GHz VOLTAGE CONTROLLED OSCILLATORS

    E-Print Network [OSTI]

    Kinget, Peter

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

  5. Is Dark Energy Abnormally Weighting?

    E-Print Network [OSTI]

    A. Fuzfa; J. -M. Alimi

    2006-09-05T23:59:59.000Z

    We present a new interpretation of dark energy in terms of an \\textit{Abnormally Weighting Energy} (AWE). This means that dark energy does not couple to gravitation in the same way as ordinary matter, yielding a violation of the weak and strong equivalence principles on cosmological scales. The resulting cosmological mechanism accounts for the Hubble diagram of type Ia supernovae in terms of both cosmic acceleration and variation of the gravitational constant while still accounting for the present tests of general relativity. This explanation allows to build dark energy models (i) without violation of the strong energy condition $p<-\\rho c^2/3$ (ii) with non-negligible direct couplings to gravitation and (iii) natural convergence mechanism toward general relativity.

  6. Electro-optic high voltage sensor

    DOE Patents [OSTI]

    Davidson, James R. (Idaho Falls, ID); Seifert, Gary D. (Idaho Falls, ID)

    2002-01-01T23:59:59.000Z

    A small sized electro-optic voltage sensor capable of accurate measurement of high levels of voltages without contact with a conductor or voltage source is provided. When placed in the presence of an electric field, the sensor receives an input beam of electromagnetic radiation into the sensor. A polarization beam displacer serves as a filter to separate the input beam into two beams with orthogonal linear polarizations. The beam displacer is oriented in such a way as to rotate the linearly polarized beams such that they enter a Pockels crystal having at a preferred angle of 45 degrees. The beam displacer is therefore capable of causing a linearly polarized beam to impinge a crystal at a desired angle independent of temperature. The Pockels electro-optic effect induces a differential phase shift on the major and minor axes of the input beam as it travels through the Pockels crystal, which causes the input beam to be elliptically polarized. A reflecting prism redirects the beam back through the crystal and the beam displacer. On the return path, the polarization beam displacer separates the elliptically polarized beam into two output beams of orthogonal linear polarization representing the major and minor axes. The system may include a detector for converting the output beams into electrical signals, and a signal processor for determining the voltage based on an analysis of the output beams. The output beams are amplitude modulated by the frequency of the electric field and the amplitude of the output beams is proportional to the magnitude of the electric field, which is related to the voltage being measured.

  7. Very-High-Frequency Resonant Boost Converters

    E-Print Network [OSTI]

    Perreault, David J.

    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 ...

  8. Temperature controlled high voltage regulator

    DOE Patents [OSTI]

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

    2004-04-20T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Vasquez, Juan Carlos

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

  10. A multilevel energy buffer and voltage modulator for grid-interfaced micro-inverters

    E-Print Network [OSTI]

    Chen, Minjie

    Micro-inverters operating into the single-phase grid from solar photovoltaic (PV) panels or other low-voltage sources must buffer the twice-line-frequency variations between the energy sourced by the PV panel and that ...

  11. A Multilevel Energy Buffer and Voltage Modulator for Grid-Interfaced Microinverters

    E-Print Network [OSTI]

    Chen, Minjie

    Microinverters operating into the single-phase grid from solar photovoltaic (PV) panels or other low-voltage sources must buffer the twice-line-frequency variations between the energy sourced by the PV panel and that ...

  12. Dynamic simulation of voltage collapses

    SciTech Connect (OSTI)

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

    1993-08-01T23:59:59.000Z

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

  13. E-beam high voltage switching power supply

    DOE Patents [OSTI]

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

    1997-01-01T23:59:59.000Z

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

  14. E-beam high voltage switching power supply

    DOE Patents [OSTI]

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

    1997-03-11T23:59:59.000Z

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

  15. High voltage electrical amplifier having a short rise time

    DOE Patents [OSTI]

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

    1991-01-01T23:59:59.000Z

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

  16. Easily disassembled electrical connector for high voltage, high frequency connections

    DOE Patents [OSTI]

    Milner, J.R.

    1994-05-10T23:59:59.000Z

    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.

  17. Dynamic Voltage and Frequency Scaling for Scientific Applications #

    E-Print Network [OSTI]

    Kremer, Ulrich

    of the processor waiting for the memory subsystem to provide the data. Minimizing the power/energy consumption energy consumption. 1 Introduction Modern architectures have a large gap between the speeds of the memory of scientific computations leads to a reduction in heat dissipation and cooling requirements, which in turn

  18. Saving Megawatts with Voltage Optimization

    E-Print Network [OSTI]

    Wilson, T.; Bell, D.

    2010-01-01T23:59:59.000Z

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

  19. Voltage tunable microwave ferrite resonator

    E-Print Network [OSTI]

    Oates, Daniel E.

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

  20. Microglial and neuronal abnormalities in the autistic brain

    E-Print Network [OSTI]

    Morgan, John T.

    2009-01-01T23:59:59.000Z

    G. , Dager, S. R. , 2002. Brain sructural abnormalities inwith autistic behavior. Brain Behav Immun 7, 97- Sparks, B.G. , Dager, S. R. , 2002. Brain sructural abnormalities in

  1. ABBGroup-1-High voltage lab

    E-Print Network [OSTI]

    Basse, Nils Plesner

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

  2. Clustering-Based Simultaneous Task and Voltage Scheduling for NoC Systems

    E-Print Network [OSTI]

    Yang, Yu

    2011-08-08T23:59:59.000Z

    - dress the voltage-frequency assignment problem for NoC. In [8], the voltage-frequency assignment and partitioning were performed after the tasks were bound to PEs and mapped to tiles. The whole procedure can be divided into two separate parts: first..., and the cluster agglomeration procedure. In the experiment, we compare our method with a sequential approach of task schedul- ing followed by voltage assignment [12]. The results show that our method can achieve 20% energy reduction on average under the same...

  3. A Matter of Quantum Voltages

    SciTech Connect (OSTI)

    Sellner, Bernhard; Kathmann, Shawn M.

    2014-11-14T23:59:59.000Z

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

  4. Development of 13-V, 5000-A DC Power Supply with High-Frequency Transformer Coupling

    E-Print Network [OSTI]

    Fujimoto, Hiroshi

    -voltage and large-current DC power supply with a high-frequency transformer coupling, which is applied to electric. Keywords-DC power supply; low-voltage and large-current; high-frequency transformer; Schottky diodeDevelopment of 13-V, 5000-A DC Power Supply with High-Frequency Transformer Coupling Applied

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

    DOE Patents [OSTI]

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

    2011-12-27T23:59:59.000Z

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

  6. The design of a frequency modulated transistor oscillator

    E-Print Network [OSTI]

    Fisher, Phil Dewey

    1959-01-01T23:59:59.000Z

    with temperature rise. c The germanium transistor, a Texas Instruments 3N365, has a maximum operating temperature of +75'C. Capacitor 06 and 0 were added to eliminate the high audio frequency noise generated by the heating of the thermistor and transistor... of the voltage applied to the modulator. The oscillator frequency deviations were measured 'by the communication receiver, crystal controlled oscillator, and electronic frequency counter method discussed on page 26. The voltage was varied in steps of 0. 0$ cf...

  7. Conservation Theory Process Control Using Variable Frequency Drives

    E-Print Network [OSTI]

    Myers, N. S.

    1980-01-01T23:59:59.000Z

    name from the vari able DC voltage which the rectifier section pro duces. Variable DC voltage is required in order to produce controlled AC with the volts per hz ratio constant. To operate an AC motor over a speed range from 5-60 hz and still... be capable of producing con stant torque,the ratio: Volts ~ = Constant must be satisfied. The rectifier and inverter stages work in concert to produce variable voltage, variable frequency AC power. The linear relation ship between voltage and frequency...

  8. Frequency stabilization in nonlinear MEMS and NEMS oscillators

    DOE Patents [OSTI]

    Lopez, Omar Daniel; Antonio, Dario

    2014-09-16T23:59:59.000Z

    An illustrative system includes an amplifier operably connected to a phase shifter. The amplifier is configured to amplify a voltage from an oscillator. The phase shifter is operably connected to a driving amplitude control, wherein the phase shifter is configured to phase shift the amplified voltage and is configured to set an amplitude of the phase shifted voltage. The oscillator is operably connected to the driving amplitude control. The phase shifted voltage drives the oscillator. The oscillator is at an internal resonance condition, based at least on the amplitude of the phase shifted voltage, that stabilizes frequency oscillations in the oscillator.

  9. Voltage, energy and power in electric circuits

    E-Print Network [OSTI]

    Berzins, M.

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

  10. Ancillary service details: Voltage control

    SciTech Connect (OSTI)

    Kirby, B.; Hirst, E.

    1997-12-01T23:59:59.000Z

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

  11. Detector for flow abnormalities in gaseous diffusion plant compressors

    DOE Patents [OSTI]

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

    1998-01-01T23:59:59.000Z

    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.

  12. Detector for flow abnormalities in gaseous diffusion plant compressors

    DOE Patents [OSTI]

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

    1998-06-16T23:59:59.000Z

    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.

  13. Motor Control Abnormalities in Parkinson's Disease

    E-Print Network [OSTI]

    Motor Control Abnormalities in Parkinson's Disease Pietro Mazzoni, Britne Shabbott, and Juan Camilo Cortes Motor Performance Laboratory, The Neurological Institute, Columbia University, New York, New. Motor symptoms can also be described in terms of motor control, a level of description that explains how

  14. High frequency reference electrode

    DOE Patents [OSTI]

    Kronberg, J.W.

    1994-05-31T23:59:59.000Z

    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.

  15. High voltage MOSFET switching circuit

    DOE Patents [OSTI]

    McEwan, T.E.

    1994-07-26T23:59:59.000Z

    The problem of source lead inductance in a MOSFET switching circuit is compensated for by adding an inductor to the gate circuit. The gate circuit inductor produces an inductive spike which counters the source lead inductive drop to produce a rectangular drive voltage waveform at the internal gate-source terminals of the MOSFET. 2 figs.

  16. High voltage MOSFET switching circuit

    DOE Patents [OSTI]

    McEwan, Thomas E. (Livermore, CA)

    1994-01-01T23:59:59.000Z

    The problem of source lead inductance in a MOSFET switching circuit is compensated for by adding an inductor to the gate circuit. The gate circuit inductor produces an inductive spike which counters the source lead inductive drop to produce a rectangular drive voltage waveform at the internal gate-source terminals of the MOSFET.

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

    E-Print Network [OSTI]

    Fujimoto, Hiroshi

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

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

    E-Print Network [OSTI]

    Gou, Jian

    1992-01-01T23:59:59.000Z

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

  19. High voltage photovoltaic power converter

    DOE Patents [OSTI]

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

    2001-01-01T23:59:59.000Z

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

  20. Abnormal reproductive function in female homozygous leaner mice

    E-Print Network [OSTI]

    Serpedin, Nesrin

    2004-09-30T23:59:59.000Z

    Major Subject: Toxicology ABNORMAL REPRODUCTIVE FUNCTION IN FEMALE HOMOZYGOUS LEANER MICE A Thesis...) (Chair of Toxicology Faculty) December 2003 Major Subject: Toxicology iii ABSTRACT Abnormal Reproductive Function in Female Homozygous...

  1. Precision absolute frequency laser spectroscopy of argon II in parallel and antiparallel geometry using a frequency comb for calibration

    E-Print Network [OSTI]

    Lioubimov, Vladimir

    2010-01-14T23:59:59.000Z

    Change in anode voltage of the ion source operation parameters. . . . 110 XII Ar II 2G7/2-2Fo5/2 transition frequency. . . . . . . . . . . . . . . . . . 116 XIII Condesor lens system parameters. . . . . . . . . . . . . . . . . . . . . 133 XIV...

  2. Carrier-frequency synchronization system for improved amplitude modulation and television broadcast reception

    DOE Patents [OSTI]

    Smith, Stephen F.; Moore, James A.

    2003-05-13T23:59:59.000Z

    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.

  3. Synchronizing carrier frequencies of co-channel amplitude-modulated broadcast

    DOE Patents [OSTI]

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

    2007-05-15T23:59:59.000Z

    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.

  4. abnormal neurological findings: Topics by E-print Network

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

    and Dissertations Summary: ??Patients with schizophrenia often exhibit structural brain abnormalities, as well as neurological soft signs, consistent with its...

  5. SCHOLARLY PAPERS Is Construction Blasting Still Abnormally Dangerous?

    E-Print Network [OSTI]

    SCHOLARLY PAPERS Is Construction Blasting Still Abnormally Dangerous? Timothy D. Stark, Ph.D., P an abnormally dangerous activity using the six factors presented in Section 520 of the Second Restatement to determine whether or not an activity is abnormally dangerous. DOI: 10.1061/ ASCE LA.1943-4170.0000037 CE

  6. SOFTWARE AGENTS IN HANDLING ABNORMAL SITUATIONS IN INDUSTRIAL PLANTS

    E-Print Network [OSTI]

    SOFTWARE AGENTS IN HANDLING ABNORMAL SITUATIONS IN INDUSTRIAL PLANTS Sami Syrjl and Seppo Kuikka. The abnormal situation handling in industrial plants is a challenging application area due to the complexity-model, abnormal situation handling, industrial plants 1. Introduction This paper is based on the work made

  7. Low power, scalable multichannel high voltage controller

    DOE Patents [OSTI]

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

    2008-03-25T23:59:59.000Z

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

  8. Low power, scalable multichannel high voltage controller

    DOE Patents [OSTI]

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

    2006-03-14T23:59:59.000Z

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

  9. Dynamic Voltage Regulation Using Distributed Energy Resources

    SciTech Connect (OSTI)

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

    2007-01-01T23:59:59.000Z

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

  10. Voltage Vehicles | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere IRaghuraji Agro IndustriesTown of Ladoga,planningFlowmeterUtah: Energydba Vision Motor CorpEIAVogtVoltage

  11. Wind Power Plant Voltage Stability Evaluation: Preprint

    SciTech Connect (OSTI)

    Muljadi, E.; Zhang, Y. C.

    2014-09-01T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

    Wohlgemuth, J.

    2013-05-01T23:59:59.000Z

    Group 3 is chartered to develop accelerated stress tests that can be used as comparative predictors of module lifetime versus stresses associated with humidity, temperature and voltage.

  13. Sacramento Area Voltage Support - Environment - Sierra Nevada...

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

    (SMUD), Roseville Electric (Roseville), and the California Independent System Operator (ISO) grid. Western prepared a Sacramento Voltage Support (SVS) Draft Environmental Impact...

  14. Automatic Fault Characterization via Abnormality-Enhanced Classification

    SciTech Connect (OSTI)

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

    2010-12-20T23:59:59.000Z

    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.

  15. 11.1 Introduction Noise (a spontaneous fluctuation in current or in voltage) is generated in all semiconductor devices.

    E-Print Network [OSTI]

    Wilamowski, Bogdan Maciej

    The thermal noise is proportional to the frequency bandwidth f. It can be represented by the voltage sourceTf. The noise power density, dPn/df = kT, is independent of frequency. Thus, the thermal noise is the white and reliability. The most important sources of noise are thermal noise, shot noise, generation-recombination noise

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

    DOE Patents [OSTI]

    Pitel, Ira J. (Whippany, NJ)

    1987-02-03T23:59:59.000Z

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

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

    DOE Patents [OSTI]

    Pitel, I.J.

    1987-02-03T23:59:59.000Z

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

  18. A Low-Voltage 77-GHz Automotive Radar Chipset Sean T. Nicolson1

    E-Print Network [OSTI]

    Voinigescu, Sorin Petre

    (VCO, LNA, PA, mixer, and static frequency divider) required to fabricate a fully integrated 2.5V, 77-noise amplifier, a novel low-voltage double-balanced Gilbert-cell mixer with two mm-wave baluns and IF amplifier achieving 12.8dB noise figure and an OP1dB of +5dBm, a 99GHz static frequency divider consuming a record low

  19. 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

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

    E-Print Network [OSTI]

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

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

  1. Wide band stepped frequency ground penetrating radar

    DOE Patents [OSTI]

    Bashforth, M.B.; Gardner, D.; Patrick, D.; Lewallen, T.A.; Nammath, S.R.; Painter, K.D.; Vadnais, K.G.

    1996-03-12T23:59:59.000Z

    A wide band ground penetrating radar system is described embodying a method wherein a series of radio frequency signals is produced by a single radio frequency source and provided to a transmit antenna for transmission to a target and reflection therefrom to a receive antenna. A phase modulator modulates those portions of the radio frequency signals to be transmitted and the reflected modulated signal is combined in a mixer with the original radio frequency signal to produce a resultant signal which is demodulated to produce a series of direct current voltage signals, the envelope of which forms a cosine wave shaped plot which is processed by a Fast Fourier Transform Unit 44 into frequency domain data wherein the position of a preponderant frequency is indicative of distance to the target and magnitude is indicative of the signature of the target. 6 figs.

  2. Wide band stepped frequency ground penetrating radar

    DOE Patents [OSTI]

    Bashforth, Michael B. (Buellton, CA); Gardner, Duane (Santa Maria, CA); Patrick, Douglas (Santa Maria, CA); Lewallen, Tricia A. (Ventura, CA); Nammath, Sharyn R. (Santa Barbara, CA); Painter, Kelly D. (Goleta, CA); Vadnais, Kenneth G. (Alexandria, VA)

    1996-01-01T23:59:59.000Z

    A wide band ground penetrating radar system (10) embodying a method wherein a series of radio frequency signals (60) is produced by a single radio frequency source (16) and provided to a transmit antenna (26) for transmission to a target (54) and reflection therefrom to a receive antenna (28). A phase modulator (18) modulates those portion of the radio frequency signals (62) to be transmitted and the reflected modulated signal (62) is combined in a mixer (34) with the original radio frequency signal (60) to produce a resultant signal (53) which is demodulated to produce a series of direct current voltage signals (66) the envelope of which forms a cosine wave shaped plot (68) which is processed by a Fast Fourier Transform unit 44 into frequency domain data (70) wherein the position of a preponderant frequency is indicative of distance to the target (54) and magnitude is indicative of the signature of the target (54).

  3. abnormal proliferative response: Topics by E-print Network

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

    in the impaired limb shoulder, flexion torque was observed in 7 subjects and shoulder abduction 15 Abnormal Psychology Psychology 280 Biology and Medicine Websites Summary:...

  4. abnormal cerebellar morphometry: Topics by E-print Network

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

    neuroimaging studies of psychopathy have demonstrated abnormal functioning in several brain regions associated with emotion and decision-making, including amygdala, orbital...

  5. abnormal grey matter: Topics by E-print Network

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

    ... Christodoulou, Joanna 13 Toward a Unified Description of Dark Energy and Dark Matter from the Abnormally Weighting Energy Hypothesis Astrophysics (arXiv) Summary: The...

  6. DECENTRALIZED VOLTAGE CONTROL TO MINIMIZE DISTRIBUTION LOSSES IN AN ISLANDED MICROGRID

    E-Print Network [OSTI]

    Peng, Huei

    to deploy renewable energy sources such as solar and wind to reduce reliance on fossil fuels. In addition by inverters, there may not exist any inertia at all. In such cases, regulating the grid frequency becomes power sources and energy storage systems such as batteries requires new power and voltage control

  7. Small-Signal Modeling of a Three-Phase Isolated Inverter with Both Voltage and

    E-Print Network [OSTI]

    Kimball, Jonathan W.

    Small-Signal Modeling of a Three-Phase Isolated Inverter with Both Voltage and Frequency Droop Rolla, Missouri 65409 Abstract-- In conventional power system operation, droop control methods are used. Both P- and Q-V droops have been used in synchronous machines for decades. Similar droop controllers

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

    DOE Patents [OSTI]

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

    1998-01-01T23:59:59.000Z

    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.

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

    DOE Patents [OSTI]

    Mikesell, H.E.; Lucy, E.

    1998-02-03T23:59:59.000Z

    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.

  10. Variable frequency microwave furnace system

    DOE Patents [OSTI]

    Bible, Don W. (Clinton, TN); Lauf, Robert J. (Oak Ridge, TN)

    1994-01-01T23:59:59.000Z

    A variable frequency microwave furnace system (10) designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity (34) for testing or other selected applications. The variable frequency microwave furnace system (10) includes a microwave signal generator (12) or microwave voltage-controlled oscillator (14) for generating a low-power microwave signal for input to the microwave furnace. A first amplifier (18) may be provided to amplify the magnitude of the signal output from the microwave signal generator (12) or the microwave voltage-controlled oscillator (14). A second amplifier (20) is provided for processing the signal output by the first amplifier (18). The second amplifier (20) outputs the microwave signal input to the furnace cavity (34). In the preferred embodiment, the second amplifier (20) is a traveling-wave tube (TWT). A power supply (22) is provided for operation of the second amplifier (20). A directional coupler (24) is provided for detecting the direction of a signal and further directing the signal depending on the detected direction. A first power meter (30) is provided for measuring the power delivered to the microwave furnace (32). A second power meter (26) detects the magnitude of reflected power. Reflected power is dissipated in the reflected power load (28).

  11. Variable frequency microwave furnace system

    DOE Patents [OSTI]

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

    1994-06-14T23:59:59.000Z

    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.

  12. Optimal Power Flow Incorporating Voltage Collapse Constraints

    E-Print Network [OSTI]

    Cañizares, Claudio A.

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

  13. Voltage regulation in linear induction accelerators

    DOE Patents [OSTI]

    Parsons, William M. (Santa Fe, NM)

    1992-01-01T23:59:59.000Z

    Improvement in voltage regulation in a Linear Induction Accelerator wherein a varistor, such as a metal oxide varistor, is placed in parallel with the beam accelerating cavity and the magnetic core. The non-linear properties of the varistor result in a more stable voltage across the beam accelerating cavity than with a conventional compensating resistance.

  14. Voltage regulation in linear induction accelerators

    DOE Patents [OSTI]

    Parsons, W.M.

    1992-12-29T23:59:59.000Z

    Improvement in voltage regulation in a linear induction accelerator wherein a varistor, such as a metal oxide varistor, is placed in parallel with the beam accelerating cavity and the magnetic core is disclosed. The non-linear properties of the varistor result in a more stable voltage across the beam accelerating cavity than with a conventional compensating resistance. 4 figs.

  15. REDUCTION OF VOLTAGE VIOLATIONS FROM EMBEDDED GENERATORS

    E-Print Network [OSTI]

    Harrison, Gareth

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

  16. Flexible method for monitoring fuel cell voltage

    DOE Patents [OSTI]

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

    2002-01-01T23:59:59.000Z

    A method for equalizing the measured voltage of each cluster in a fuel cell stack wherein at least one of the clusters has a different number of cells than the identical number of cells in the remaining clusters by creating a pseudo voltage for the different cell numbered cluster. The average cell voltage of the all of the cells in the fuel cell stack is calculated and multiplied by a constant equal to the difference in the number of cells in the identical cell clusters and the number of cells in the different numbered cell cluster. The resultant product is added to the actual voltage measured across the different numbered cell cluster to create a pseudo voltage which is equivalent in cell number to the number of cells in the other identical numbered cell clusters.

  17. Corona and Motor Voltage Interim Report

    SciTech Connect (OSTI)

    Hsu, J.S.

    2005-05-06T23:59:59.000Z

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

  18. Non-contact current and voltage sensor

    DOE Patents [OSTI]

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

    2014-03-25T23:59:59.000Z

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

  19. Wide-range voltage modulation

    SciTech Connect (OSTI)

    Rust, K.R.; Wilson, J.M.

    1992-06-01T23:59:59.000Z

    The Superconducting Super Collider`s Medium Energy Booster Abort (MEBA) kicker modulator will supply a current pulse to the abort magnets which deflect the proton beam from the MEB ring into a designated beam stop. The abort kicker will be used extensively during testing of the Low Energy Booster (LEB) and the MEB rings. When the Collider is in full operation, the MEBA kicker modulator will abort the MEB beam in the event of a malfunction during the filling process. The modulator must generate a 14-{mu}s wide pulse with a rise time of less than 1 {mu}s, including the delay and jitter times. It must also be able to deliver a current pulse to the magnet proportional to the beam energy at any time during ramp-up of the accelerator. Tracking the beam energy, which increases from 12 GeV at injection to 200 GeV at extraction, requires the modulator to operate over a wide range of voltages (4 kV to 80 kV). A vacuum spark gap and a thyratron have been chosen for test and evaluation as candidate switches for the abort modulator. Modulator design, switching time delay, jitter and pre-fire data are presented.

  20. PH-315 A. La Rosa VOLTAGE-CONTROLLED OSCILLATOR

    E-Print Network [OSTI]

    PH-315 A. La Rosa VOLTAGE-CONTROLLED OSCILLATOR 1. PURPOSE: An integrator and a Schmitt Trigger voltage; hence its name "voltage-controlled oscillator." 2. VOLTAGE-CONTROLLED OSCILLATOR Figure 1 shows voltage. An unusual feature of the circuit is its operation using a single positive supply.1 #12;- + 50k V

  1. Electro-optical voltage sensor head

    DOE Patents [OSTI]

    Woods, Gregory K. (Idaho Falls, ID)

    1998-01-01T23:59:59.000Z

    A miniature electro-optic voltage sensor system capable of accurate operation at high voltages. The system employs a transmitter, a sensor disposed adjacent to but out of direct electrical contact with a conductor on which the voltage is to be measured, a detector, and a signal processor. The transmitter produces a beam of electromagnetic radiation which is routed into the sensor where the beam undergoes the Pockels electro-optic effect. The electro-optic effect causes phase shifting in the beam, which is in turn converted to a pair of independent beams, from which the voltage of a system based on its E-field is determined when the two beams are normalized by the signal processor. The sensor converts the beam by splitting the beam in accordance with the axes of the beam's polarization state (an ellipse whose ellipticity varies between -1 and +1 in proportion to voltage) into at least two AM signals. These AM signals are fed into a signal processor and processed to determine the voltage between a ground conductor and the conductor on which voltage is being measured.

  2. Voltage instability: Mechanisms and control strategies

    SciTech Connect (OSTI)

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

    1995-11-01T23:59:59.000Z

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

  3. Modular high voltage power supply for chemical analysis

    DOE Patents [OSTI]

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

    2010-05-04T23:59:59.000Z

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

  4. Modular high voltage power supply for chemical analysis

    SciTech Connect (OSTI)

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

    2007-01-09T23:59:59.000Z

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

  5. Modular high voltage power supply for chemical analysis

    SciTech Connect (OSTI)

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

    2008-07-15T23:59:59.000Z

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

  6. Voltage Management of Networks with Distributed Generation.

    E-Print Network [OSTI]

    O'Donnell, James

    2008-01-01T23:59:59.000Z

    At present there is much debate about the impacts and benefits of increasing the amount of generation connected to the low voltage areas of the electricity distribution network. The UK government is under political ...

  7. Electro-optic high voltage sensor

    DOE Patents [OSTI]

    Davidson, James R.; Seifert, Gary D.

    2003-09-16T23:59:59.000Z

    A small sized electro-optic voltage sensor capable of accurate measurement of high voltages without contact with a conductor or voltage source is provided. When placed in the presence of an electric field, the sensor receives an input beam of electromagnetic radiation. A polarization beam displacer separates the input beam into two beams with orthogonal linear polarizations and causes one linearly polarized beam to impinge a crystal at a desired angle independent of temperature. The Pockels effect elliptically polarizes the beam as it travels through the crystal. A reflector redirects the beam back through the crystal and the beam displacer. On the return path, the polarization beam displacer separates the elliptically polarized beam into two output beams of orthogonal linear polarization. The system may include a detector for converting the output beams into electrical signals and a signal processor for determining the voltage based on an analysis of the output beams.

  8. Low voltage arc formation in railguns

    DOE Patents [OSTI]

    Hawke, R.S.

    1987-11-17T23:59:59.000Z

    A low voltage plasma arc is first established across the rails behind the projectile by switching a low voltage high current source across the rails to establish a plasma arc by vaporizing a fuse mounted on the back of the projectile, maintaining the voltage across the rails below the railgun breakdown voltage to prevent arc formation ahead of the projectile. After the plasma arc has been formed behind the projectile a discriminator switches the full energy bank across the rails to accelerate the projectile. A gas gun injector may be utilized to inject a projectile into the breech of a railgun. The invention permits the use of a gas gun or gun powder injector and an evacuated barrel without the risk of spurious arc formation in front of the projectile. 2 figs.

  9. Low voltage arc formation in railguns

    DOE Patents [OSTI]

    Hawke, Ronald S. (Livermore, CA)

    1987-01-01T23:59:59.000Z

    A low voltage plasma arc is first established across the rails behind the projectile by switching a low voltage high current source across the rails to establish a plasma arc by vaporizing a fuse mounted on the back of the projectile, maintaining the voltage across the rails below the railgun breakdown voltage to prevent arc formation ahead of the projectile. After the plasma arc has been formed behind the projectile a discriminator switches the full energy bank across the rails to accelerate the projectile. A gas gun injector may be utilized to inject a projectile into the breech of a railgun. The invention permits the use of a gas gun or gun powder injector and an evacuated barrel without the risk of spurious arc formation in front of the projectile.

  10. Low voltage arc formation in railguns

    DOE Patents [OSTI]

    Hawke, R.S.

    1985-08-05T23:59:59.000Z

    A low voltage plasma arc is first established across the rails behind the projectile by switching a low voltage high current source across the rails to establish a plasma arc by vaporizing a fuse mounted on the back of the projectile, maintaining the voltage across the rails below the railgun breakdown voltage to prevent arc formation ahead of the projectile. After the plasma arc has been formed behind the projectile a discriminator switches the full energy bank across the rails to accelerate the projectile. A gas gun injector may be utilized to inject a projectile into the breech of a railgun. The invention permits the use of a gas gun or gun powder injector and an evacuated barrel without the risk of spurious arc formation in front of the projectile.

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

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

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

  12. High-Voltage Solid Polymer Batteries for Electric Drive Vehicles...

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

    High-Voltage Solid Polymer Batteries for Electric Drive Vehicles High-Voltage Solid Polymer Batteries for Electric Drive Vehicles 2012 DOE Hydrogen and Fuel Cells Program and...

  13. Addressing the Voltage Fade Issue with Lithium-Manganese-Rich...

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

    Addressing the Voltage Fade Issue with Lithium-Manganese-Rich Oxide Cathode Materials Addressing the Voltage Fade Issue with Lithium-Manganese-Rich Oxide Cathode Materials 2013 DOE...

  14. Addressing the Voltage Fade Issue with Lithium-Manganese-Rich...

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

    Voltage Fade Issue with Lithium-Manganese-Rich Oxide Cathode Materials Addressing the Voltage Fade Issue with Lithium-Manganese-Rich Oxide Cathode Materials 2012 DOE Hydrogen and...

  15. Constant voltage electro-slag remelting control

    DOE Patents [OSTI]

    Schlienger, M.E.

    1996-10-22T23:59:59.000Z

    A system for controlling electrode gap in an electro-slag remelt furnace has a constant regulated voltage and an electrode which is fed into the slag pool at a constant rate. The impedance of the circuit through the slag pool is directly proportional to the gap distance. Because of the constant voltage, the system current changes are inversely proportional to changes in gap. This negative feedback causes the gap to remain stable. 1 fig.

  16. Group 3: Humidity, Temperature, and Voltage

    Broader source: Energy.gov [DOE]

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

  17. Spark gap with low breakdown voltage jitter

    DOE Patents [OSTI]

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

    1996-01-01T23:59:59.000Z

    Novel spark gap devices and electrodes are disclosed. The novel spark gap devices and electrodes are suitable for use in a variety of spark gap device applications. The shape of the electrodes gives rise to local field enhancements and reduces breakdown voltage jitter. Breakdown voltage jitter of approximately 5% has been measured in spark gaps according the invention. Novel electrode geometries and materials are disclosed.

  18. Spark gap with low breakdown voltage jitter

    DOE Patents [OSTI]

    Rohwein, G.J.; Roose, L.D.

    1996-04-23T23:59:59.000Z

    Novel spark gap devices and electrodes are disclosed. The novel spark gap devices and electrodes are suitable for use in a variety of spark gap device applications. The shape of the electrodes gives rise to local field enhancements and reduces breakdown voltage jitter. Breakdown voltage jitter of approximately 5% has been measured in spark gaps according the invention. Novel electrode geometries and materials are disclosed. 13 figs.

  19. High-frequency electric field measurement using a toroidal antenna

    DOE Patents [OSTI]

    Lee, Ki Ha (Lafayette, CA)

    2002-01-01T23:59:59.000Z

    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.

  20. hal-00175072,version1-26Sep2007 Current to frequency conversion in a Josephson circuit

    E-Print Network [OSTI]

    Boyer, Edmond

    (Dated: September 26, 2007) The voltage oscillations which occur in an ideally current-biased Josephson in particular that the voltage across the junction (particle velocity) oscillates at the Bloch frequency fB = I junction, were pro- posed to make a current standard for metrology [1]. We demonstrate similar oscillations

  1. InGaP/InGaAs doped-channel direct-coupled field-effect transistors logic with low supply voltage

    SciTech Connect (OSTI)

    Tsai, Jung-Hui, E-mail: jbtsai@nknucc.nknu.edu.tw [National Kaohsiung Normal University, Department of Electronic Engineering (China); Lour, Wen-Shiung [National Taiwan Ocean University, Department of Electrical Engineering (China); Weng Tzuyen; Li Chienming [National Kaohsiung Normal University (China)

    2010-02-15T23:59:59.000Z

    InGaP/InGaAs doped-channel direct-coupled field-effect transistor logic (DCFL) with relatively low supple voltage is demonstrated by two-dimensional analysis. In the integrated enhancement/depletion-mode transistors, subband and two-dimensional electron gas (2DEG) are formed in the InGaAs strain channels, which substantially increase the channel concentration and decrease the drain-to-source saturation voltage. The integrated devices show high turn-on voltage, high transconductance, broad gate voltage swing, and excellent high frequency performance, simultaneously. Furthermore, the integrated devices exhibit large noise margins for DCFL application with low supply voltage of 1.5 V attributed from the relatively small saturation voltages of the studied integrated devices.

  2. Factors that influence follow-up after an abnormal mammogram

    E-Print Network [OSTI]

    Copeland, Valerie Anne

    2009-05-15T23:59:59.000Z

    The focus of this study was to explore womens experiences with follow-up after an abnormal mammogram, and factors that influence follow-up. Factors, including health status, found in the cancer screening and treatment ...

  3. abnormalities drug-induced: Topics by E-print Network

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

    for cultured NIH 3T3 cells. The occurrence of the abnormality was mediated by the formation of focal adhesions. H. -a. Pan; C. -w. Su; S. -m. Tai; F. -h. Ko; G. Steve...

  4. Factors that influence follow-up after an abnormal mammogram

    E-Print Network [OSTI]

    Copeland, Valerie Anne

    2009-05-15T23:59:59.000Z

    breast self-examination and complying with diagnostic tests. A non-experimental, descriptive, cross-sectional design was used to identify the barriers to follow-up after an abnormal mammogram by: 1) determining the noncompliance rate of follow...

  5. Psychophysical Indexes of Temporal Processing Abnormalities in Children

    E-Print Network [OSTI]

    Dougherty, Bob

    Psychophysical Indexes of Temporal Processing Abnormalities in Children With Developmental Dyslexia of Ophthalmology University of British Columbia, Canada Children with dyslexia and children progressing normally differen- tiate children with dyslexia from children with average reading abilities; (b) the ex- tent

  6. ABNORMAL BEHAVIOR DETECTION AND BEHAVIOR MATCHING FOR NETWORKED CAMERAS

    E-Print Network [OSTI]

    Jodoin, Pierre-Marc

    segmentation I. INTRODUCTION Network video cameras permit pervasive, wide-area visual surveillance. However-100362, Presidential Early Career Award (PECASE) behavior model at various regions of the frame, and performs abnormal

  7. abnormal energy metabolism: Topics by E-print Network

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

    11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Is Dark Energy Abnormally Weighting? Astrophysics (arXiv) Summary: We present a new interpretation of...

  8. abnormally weighting energy: Topics by E-print Network

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

    11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Is Dark Energy Abnormally Weighting? Astrophysics (arXiv) Summary: We present a new interpretation of...

  9. abnormal energy shift: Topics by E-print Network

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

    11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Is Dark Energy Abnormally Weighting? Astrophysics (arXiv) Summary: We present a new interpretation of...

  10. High Precision Noise Measurements at Microwave Frequencies

    SciTech Connect (OSTI)

    Ivanov, Eugene; Tobar, Michael [School of Physics, University of Western Australia, 35 Stirling Hwy., Crawley, 6009, WA (Australia)

    2009-04-23T23:59:59.000Z

    We describe microwave noise measurement system capable of detecting the phase fluctuations of rms amplitude of 2{center_dot}10{sup -11} rad/{radical}(Hz). Such resolution allows the study of intrinsic fluctuations in various microwave components and materials, as well as precise tests of fundamental physics. Employing this system we discovered a previously unknown phenomenon of down-conversion of pump oscillator phase noise into the low-frequency voltage fluctuations.

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

    DOE Patents [OSTI]

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

    1987-07-30T23:59:59.000Z

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

  12. Droop Compensation with soft Switching for High Voltage Converter Modulator (HVCM)

    SciTech Connect (OSTI)

    Bland, Michael [University of Nottingham; Scheinker, Alexander [Los Alamos National Laboratory; Clare, Jon [University of Nottingham; Watson, Alan [University of Nottingham; Ji, Chao [University of Nottingham; Reass, William [Los Alamos National Laboratory

    2012-06-04T23:59:59.000Z

    High Voltage Converter Modulators (HVCM) offer significant performance advantages over conventional modulator technologies for long pulse applications. One of the key advantages of HVCM technology is the ability to compensate for capacitor bank voltage droop. Achieving droop compensation without incurring significant additional switching loss has not been possible in existing designs. This paper presents an analysis of the 'Y-point' variant of the HVCM topology using the Combined Phase and Frequency Modulation (CPFM) technique. This, combined with the addition of a 'lossless' snubber circuit, enables droop compensation while achieving soft switching over the entire pulse duration. The rise time and overshoot of the output voltage pulse is optimized using an iterative extreme seeking algorithm. The optimization reduces the rise time from 100 {micro}s to 50 {micro}s with no overshoot. This will lead to an increase in overall accelerator efficiency.

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

    E-Print Network [OSTI]

    Amirabadi, Mahshid

    2013-08-07T23:59:59.000Z

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

  14. An accurate continuous calibration system for high voltage current transformer

    SciTech Connect (OSTI)

    Tong Yue; Li Binhong [College of Electrical and Electronic Engineering, Huazhong University of Science and Technology, Wuhan 430074, Hubei Province (China)

    2011-02-15T23:59:59.000Z

    A continuous calibration system for high voltage current transformers is presented in this paper. The sensor of this system is based on a kind of electronic instrument current transformer, which is a clamp-shape air core coil. This system uses an optical fiber transmission system for its signal transmission and power supply. Finally the digital integrator and fourth-order convolution window algorithm as error calculation methods are realized by the virtual instrument with a personal computer. It is found that this system can calibrate a high voltage current transformer while energized, which means avoiding a long calibrating period in the power system and the loss of power metering expense. At the same time, it has a wide dynamic range and frequency band, and it can achieve a high accuracy measurement in a complex electromagnetic field environment. The experimental results and the on-site operation results presented in the last part of the paper, prove that it can reach the 0.05 accuracy class and is easy to operate on site.

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

    SciTech Connect (OSTI)

    Liu, E.; Bebic, J.

    2008-02-01T23:59:59.000Z

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

  16. Chapter 17. High-Voltage Systems and Dielectric Materials High-Voltage Systems and Dielectric Materials

    E-Print Network [OSTI]

    -Voltage Systems and Dielectric Materials 17-2 RLE Progress Report 152 provides very useful insight into pre-breakdown in high voltage conduction and breakdown phenomena. 1. Mechanisms Behind Positive Streamers and Their Distinct Propagation Modes in Transformer Oil Sponsors This work was supported by ABB Corporate Research

  17. A Charge Pump that Generates Negative High Voltage with Variable Voltage , Eugene Ivanova,

    E-Print Network [OSTI]

    Ayers, Joseph

    A Charge Pump that Generates Negative High Voltage with Variable Voltage Gain Jun Zhaob, , Eugene, Massachusetts 02115, U.S.A. Abstract A cross-coupled structure based charge pump that generates negative high. The proposed negative charge pump is designed to deliver 40 uA with a wide supply range from 2.5V to 5.5V using

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

    E-Print Network [OSTI]

    Dimarogonas, Dimos

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

  19. Electronic circuit for measuring series connected electrochemical cell voltages

    DOE Patents [OSTI]

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

    2000-01-01T23:59:59.000Z

    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.

  20. Compact high voltage solid state switch

    DOE Patents [OSTI]

    Glidden, Steven C.

    2003-09-23T23:59:59.000Z

    A compact, solid state, high voltage switch capable of high conduction current with a high rate of current risetime (high di/dt) that can be used to replace thyratrons in existing and new applications. The switch has multiple thyristors packaged in a single enclosure. Each thyristor has its own gate drive circuit that circuit obtains its energy from the energy that is being switched in the main circuit. The gate drives are triggered with a low voltage, low current pulse isolated by a small inexpensive transformer. The gate circuits can also be triggered with an optical signal, eliminating the trigger transformer altogether. This approach makes it easier to connect many thyristors in series to obtain the hold off voltages of greater than 80 kV.

  1. Electro-optic voltage sensor for sensing voltage in an E-field

    DOE Patents [OSTI]

    Woods, Gregory K. (Idaho Falls, ID); Renak, Todd W. (Idaho Falls, ID)

    1999-01-01T23:59:59.000Z

    A miniature electro-optic voltage sensor system capable of accurate operation at high voltages. The system employs a transmitter, a sensor disposed adjacent to but out of direct electrical contact with a conductor on which the voltage is to be measured, a detector, and a signal processor. The transmitter produces a beam of electromagnetic radiation which is routed into the sensor where the beam undergoes the Pockels electro-optic effect. The electro-optic effect causes phase shifting in the beam, which is in turn converted to a pair of independent beams, from which the voltage of a system based on its E-field is determined when the two beams are normalized by the signal processor. The sensor converts the beam by splitting the beam in accordance with the axes of the beam's polarization state (an ellipse whose ellipticity varies between -1 and +1 in proportion to voltage) into at least two AM signals. These AM signals are fed into a signal processor and processed to determine the voltage between a ground conductor and the conductor on which voltage is being measured.

  2. Electro-optic voltage sensor for sensing voltage in an E-field

    DOE Patents [OSTI]

    Woods, G.K.; Renak, T.W.

    1999-04-06T23:59:59.000Z

    A miniature electro-optic voltage sensor system capable of accurate operation at high voltages is disclosed. The system employs a transmitter, a sensor disposed adjacent to but out of direct electrical contact with a conductor on which the voltage is to be measured, a detector, and a signal processor. The transmitter produces a beam of electromagnetic radiation which is routed into the sensor where the beam undergoes the Pockels electro-optic effect. The electro-optic effect causes phase shifting in the beam, which is in turn converted to a pair of independent beams, from which the voltage of a system based on its E-field is determined when the two beams are normalized by the signal processor. The sensor converts the beam by splitting the beam in accordance with the axes of the beam`s polarization state (an ellipse whose ellipticity varies between -1 and +1 in proportion to voltage) into at least two AM signals. These AM signals are fed into a signal processor and processed to determine the voltage between a ground conductor and the conductor on which voltage is being measured. 18 figs.

  3. Voltage control on a train system

    DOE Patents [OSTI]

    Gordon, Susanna P.; Evans, John A.

    2004-01-20T23:59:59.000Z

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

  4. High Voltage Electrolyte for Lithium Batteries

    Broader source: Energy.gov (indexed) [DOE]

    Argonne's Fluorinated Compounds as High Voltage Electrolytes (HVEs) O O O O O O EC EMC O O O CF CF 3 CF 3 O O O CF 3 F 2 HC C F 2 O F 2 C CF 2 H 6 Code Name Chemical...

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

    SciTech Connect (OSTI)

    Wohlgemuth, J.

    2013-09-01T23:59:59.000Z

    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.

  6. Method of detecting system function by measuring frequency response

    DOE Patents [OSTI]

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

    2012-04-03T23:59:59.000Z

    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.

  7. Methods and systems for detecting abnormal digital traffic

    DOE Patents [OSTI]

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

    2011-03-22T23:59:59.000Z

    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.

  8. Excimer laser phototherapy for the dissolution of abnormal growth

    DOE Patents [OSTI]

    Gruen, D.M.; Young, C.E.; Pellin, M.J.

    1985-02-19T23:59:59.000Z

    Removal of abnormal human tissue with reduced thermal damage is achieved by selecting a laser having a wavelength in the order of 290 to 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. 6 figs.

  9. Distribution System Voltage Regulation by Distributed Energy Resources

    SciTech Connect (OSTI)

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

    2014-01-01T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Tolbert, Leon M.

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

  11. abnormal thalamocortical dynamics: Topics by E-print Network

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

    abnormal thalamocortical dynamics First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Clinical Study...

  12. DETECTING ABNORMAL FISH TRAJECTORIES USING CLUSTERED AND LABELED DATA

    E-Print Network [OSTI]

    Fisher, Bob

    DETECTING ABNORMAL FISH TRAJECTORIES USING CLUSTERED AND LABELED DATA Cigdem Beyan, Robert B We propose an approach for the analysis of fish trajectories in unconstrained underwater videos. Trajectories are classified into two classes: normal trajectories which contain the usual behavior of fish

  13. abnormal pap test: Topics by E-print Network

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

    abnormal pap test First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Pap Smear Test Goruntulerinde Hucre C...

  14. Managing Abnormal Operation through Process Integration and Cogeneration Systems

    E-Print Network [OSTI]

    Kamrava, Serveh

    2014-08-05T23:59:59.000Z

    & Webster Company, Linde company method. *Part of this chapter is reprinted with permission from Managing abnormal operation through process integration and cogeneration systems by Serveh... (75% for ethane to 28% for hydrogenated gasoline). In Linde method ethylene and propylene is produced from ethane to naphta hydrocarbons by thermal cracking method. Ethylene efficiency is different for different feedstock. For gasoline, naphta...

  15. abnormal brain mri: Topics by E-print Network

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

    abnormal brain mri First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Improvement of MRI brain...

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

    E-Print Network [OSTI]

    Gross, George

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

  17. Electrical system architecture having high voltage bus

    DOE Patents [OSTI]

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

    2011-03-22T23:59:59.000Z

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

  18. Low Voltage White Phosphorescent OLED Achievements

    Broader source: Energy.gov [DOE]

    Universal Display Corporation (UDC) and its research partners at Princeton University and the University of Southern California have succeeded in developing a white phosphorescent OLED (PHOLED) that achieved a record efficiency of 20 lumens per watt. This achievement is the result of the team's collaborative efforts to increase the efficiency of PHOLED lighting by focusing on two critical factors: lowering the drive voltages and increasing the amount of light extracted.

  19. High Voltage Electrolyte for Lithium Batteries

    Broader source: Energy.gov (indexed) [DOE]

    5.0E-04 1.0E-03 2 2.2 2.4 2.6 2.8 Voltage (V) dQdV (AhV) 1 st Charge 1.2M LiPF 6 ECEMC 37 1 st Charge 1.0M LiPF 6 TMS1NM3 55 with 2% and 4% VC 1 st Charge 1.0M LiPF 6 TMS...

  20. Electrostatically screened, voltage-controlled electrostatic chuck

    DOE Patents [OSTI]

    Klebanoff, Leonard Elliott (San Ramon, CA)

    2001-01-01T23:59:59.000Z

    Employing an electrostatically screened, voltage-controlled electrostatic chuck particularly suited for holding wafers and masks in sub-atmospheric operations will significantly reduce the likelihood of contaminant deposition on the substrates. The electrostatic chuck includes (1) an insulator block having a outer perimeter and a planar surface adapted to support the substrate and comprising at least one electrode (typically a pair of electrodes that are embedded in the insulator block), (2) a source of voltage that is connected to the at least one electrode, (3) a support base to which the insulator block is attached, and (4) a primary electrostatic shield ring member that is positioned around the outer perimeter of the insulator block. The electrostatic chuck permits control of the voltage of the lithographic substrate; in addition, it provides electrostatic shielding of the stray electric fields issuing from the sides of the electrostatic chuck. The shielding effectively prevents electric fields from wrapping around to the upper or front surface of the substrate, thereby eliminating electrostatic particle deposition.

  1. Electro-optic voltage sensor head

    DOE Patents [OSTI]

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

    1999-01-01T23:59:59.000Z

    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.

  2. Electro-optic voltage sensor head

    DOE Patents [OSTI]

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

    1999-08-17T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

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

    2011-10-15T23:59:59.000Z

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

  4. abnormal doppler enteral: Topics by E-print Network

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

    The time series analysis of Doppler velocity maps show enhanced power in the sunspot umbra at higher frequencies and in the penumbra at lower frequencies. We find that the peak...

  5. Loop-voltage tomography in tokamaks using transient synchrotron radiation

    SciTech Connect (OSTI)

    Fisch, N.J.; Kritz, A.H. (Princeton Univ., NJ (USA). Plasma Physics Lab.; Hunter Coll., New York, NY (USA). Dept. of Physics)

    1989-07-01T23:59:59.000Z

    The loop voltage in tokamaks is particularly difficult to measure anywhere but at the plasma periphery. A brief, deliberate, perturbation of hot plasma electrons, however, produces a transient radiation response that is sensitive to this voltage. We investigate how such a radiation response can be used to diagnose the loop voltage. 24 refs., 6 figs.

  6. Characterized ideal LC circuit Charge, current and voltage vary sinusoidally

    E-Print Network [OSTI]

    Bertulani, Carlos A. - Department of Physics and Astronomy, Texas A&M University

    resistance to LC circuit Oscillations become damped Charge, current and voltage still vary sinusoidally Oscillations Draw phasors for voltages of R, C and L at same time t Orient VR, VL, & VC phasors relativeReview Characterized ideal LC circuit Charge, current and voltage vary sinusoidally Added

  7. Accurately measuring current-voltage characteristics of tunnel diodes

    E-Print Network [OSTI]

    Bao, Mingqiang; Wang, Kang L

    2006-01-01T23:59:59.000Z

    of the bias voltage range of oscillations in the IV curve.and the bias voltage range of oscillation in the IV curve.or to know the exact voltage range of oscillation in the IV

  8. DCS1800/WCDMA ADAPTIVE VOLTAGE-CONTROLLED OSCILLATOR

    E-Print Network [OSTI]

    Serdijn, Wouter A.

    DCS1800/WCDMA ADAPTIVE VOLTAGE-CONTROLLED OSCILLATOR Aleksandar Tasi, Wouter A. Serdijn and John R, an adaptive 2G/3G voltage-controlled oscillator (VCO) is described in this paper. For the DCS1800 operation with this reasoning, an adaptive 2G/3G voltage- controlled oscillator, meant for a dual-standard adaptive front

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

    E-Print Network [OSTI]

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

  10. Selective compensation of voltage harmonics in grid-connected microgrids

    E-Print Network [OSTI]

    Vasquez, Juan Carlos

    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

  11. Structural Optimization of High Voltage Transmission Line Towers considering

    E-Print Network [OSTI]

    Colominas, Ignasi

    Structural Optimization of High Voltage Transmission Line Towers considering Continuum and Discrete/or to common designs largely repeated (e.g. automotive compo- nents), and high voltage transmission towers can than conventional designs of high voltage transmission line towers. The optimization model proposed

  12. System for increasing corona inception voltage of insulating oils

    DOE Patents [OSTI]

    Rohwein, G.J.

    1998-05-19T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    Yang, Qing

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

  14. Energy-aware Workflow Scheduling Using Frequency Scaling Ilia Pietri, Rizos Sakellariou

    E-Print Network [OSTI]

    Sakellariou, Rizos

    when overall energy consumption can be decreased. Synthetic data based on parameters of real scientific overall energy consumption. Keywords-energy-aware scheduling; frequency scaling; DVFS; DAG scheduling to a respective voltage level [3]. Lowering the frequency may lead to decreased energy consumption

  15. Extremely high frequency RF effects on electronics.

    SciTech Connect (OSTI)

    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

    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.

  16. Improvement of breakdown voltage in InGaP/InGaAs/GaAs heterostructure MESFETs for MMICs

    SciTech Connect (OSTI)

    Koh, Inoue; Yamane, Yasuro; Shiojima, Kenji [NTT LSI Lab., Kanagawa (Japan)] [and others

    1995-12-31T23:59:59.000Z

    This paper describes the trade-off between breakdown voltage and RF performance of InGaP/InGaAs/GaAs heterostructure MESFETs for power amplifiers and oscillators in multi-function MMICs in the millimeter-wave range. The authors successfully improved both gate-drain and drain-source breakdown voltages while maintaining excellent high-frequency performance by using a double-layered gate consisting of WSiN with different nitrogen contents, and by varying epitaxial layer thickness and implantation dose.

  17. Coupling effects in inductive discharges with radio frequency substrate biasing

    SciTech Connect (OSTI)

    Schulze, J.; Schuengel, E.; Czarnetzki, U.

    2012-01-09T23:59:59.000Z

    Low pressure inductively coupled plasmas (ICP) operated in neon at 27.12 MHz with capacitive substrate biasing (CCP) at 13.56 MHz are investigated by phase resolved optical emission spectroscopy, voltage, and current measurements. Three coupling mechanisms are found potentially limiting the separate control of ion energy and flux: (i) Sheath heating due to the substrate biasing affects the electron dynamics even at high ratios of ICP to CCP power. At fixed CCP power, (ii) the substrate sheath voltage and (iii) the amplitude as well as frequency of plasma series resonance oscillations of the RF current are affected by the ICP power.

  18. Frequency Measurement & Analysis Service

    E-Print Network [OSTI]

    Magee, Joseph W.

    NIST Frequency Measurement & Analysis Service #12;A Complete Solution To All Frequency Measurement & Calibration Problems The NIST Frequency Measurement and Analysis Service makes it easy to measure and calibrate any quartz, rubidium, or cesium frequency standard. All measurements are made automatically

  19. Method of Controlling Corona Effects and Breakdown Voltage of Small Air Gaps Stressed by Impulse Voltages

    E-Print Network [OSTI]

    Athanasios Maglaras; Trifon Kousiouris; Frangiskos Topalis; Dimitrios Katsaros; Leandros A. Maglaras; Konstantina Giannakopoulou

    2014-10-15T23:59:59.000Z

    This paper investigates the influence of a resistor on the dielectric behavior of an air gap. The resistor is connected in series with the air gap and the latter is stressed by impulse voltage. Air gap arrangements of different geometry with either the rod or the plate grounded are stressed with impulse voltages of both positive and negative polarity. The resistor is connected in series with the air gap in the return circuit connecting the gap with the impulse generator. The method followed involves the investigation of the graphs of the charging time concerning the air gaps capacitances, in connection to the value of the resistor, the geometry of the gap, the effect of grounding and the polarity effect. It is determined that the charging time of the air gap increases, as the value of the resistor increases. It is also determined that the peak voltage value of the fully charged air gap decreases as the value of the resistor increases. The results of the mathematical and simulation analysis are compared with the results of the oscillograms taken from experimental work. In addition and consequently to the above results it is concluded from the experimental work that the in series connection of the resistor in the circuit has significant influence on corona pulses (partial discharges) occurring in the gap and on the breakdown voltage of the gap. A new method of controlling the corona effects and consequently the breakdown voltage of small air gaps stressed by impulse voltage of short duration in connection to the ground effect and the polarity effect has arisen. Furthermore through mathematical analysis of the charging graphs obtained from simulation and experimental oscillograms there was a calculation of the values of the capacitance of the air gaps in relation to their geometry and the results were compared to the values calculated with mathematical analysis.

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

    E-Print Network [OSTI]

    Amro, Rami

    2012-01-01T23:59:59.000Z

    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 par...

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

    SciTech Connect (OSTI)

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

    1997-04-01T23:59:59.000Z

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

  2. The effects of variations in the photocathode voltages of electronic streak cameras

    SciTech Connect (OSTI)

    Bowers, M.W.; Biggs, G.L.; Ronchetto, J.J.; Teruya, A.T.

    1988-08-08T23:59:59.000Z

    Electronic streak cameras are used to record subnanosecond data at the Nevada Test Site. It has been found that externally induced variations in the photocathode voltage of the streak tube can produce both temporal and spatial errors on the output image. An electron beam tracing code was used to model the magnification as a function of photocathode voltage and signal input position for streak tubes manufactured by RCA, ITT, and Kentech. Laboratory tests were also performed where pulsed and radio frequency signals were induced upon the photocathode and the errors on the resultant image were compared with the error predicted by the electron beam code. Also, methods for processing the distortion in digitized images were investigated. This paper will discuss the results of these investigations. 3 refs., 17 figs.

  3. Apparatus for producing voltage and current pulses

    DOE Patents [OSTI]

    Kirbie, Hugh (Los Alamos, NM); Dale, Gregory E. (Los Alamos, NM)

    2010-12-21T23:59:59.000Z

    An apparatus having one or more modular stages for producing voltage and current pulses. Each module includes a diode charging means to charge a capacitive means that stores energy. One or more charging impedance means are connected to the diode charging means to provide a return current pathway. A solid-state switch discharge means, with current interruption capability, is connected to the capacitive means to discharge stored energy. Finally, a control means is provided to command the switching action of the solid-state switch discharge means.

  4. Production of high voltage by ion bombardment

    E-Print Network [OSTI]

    Phinney, Lucas Carter

    2003-01-01T23:59:59.000Z

    . . . 35 FIGIJRE Page 19 I-V curve for the ammeter setup . . 35 20 Diagram of the leakage current test setup . . . . . . 37 21 Voltmeter readings at each high voltage interval . . . . . , 38 CHAPTER I INTRODUCTION Direct energy conversion... streaming into the source There is also a moveable shutter that can stop the beam &om entering the beam line. A Varian VHS-6 diffusion pump is connected at the bottom of the glass cross. Its function is to maintain a vacuum in this part of the accelerator...

  5. Eliminate Voltage Unbalance | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the YouTube|6721 Federal Register / Vol.6:Energy|Electrifyingof EnergyVoltage

  6. Voltage sensing systems and methods for passive compensation of temperature related intrinsic phase shift

    DOE Patents [OSTI]

    Davidson, James R. (Idaho Falls, ID); Lassahn, Gordon D. (Idaho Falls, ID)

    2001-01-01T23:59:59.000Z

    A small sized electro-optic voltage sensor capable of accurate measurement of high levels of voltages without contact with a conductor or voltage source is provided. When placed in the presence of an electric field, the sensor receives an input beam of electromagnetic radiation into the sensor. A polarization beam displacer serves as a filter to separate the input beam into two beams with orthogonal linear polarizations. The beam displacer is oriented in such a way as to rotate the linearly polarized beams such that they enter a Pockels crystal at a preferred angle of 45 degrees. The beam displacer is therefore capable of causing a linearly polarized beam to impinge a crystal at a desired angle independent of temperature. The Pockels electro-optic effect induces a differential phase shift on the major and minor axes of the input beam as it travels through the Pockels crystal, which causes the input beam to be elliptically polarized. A reflecting prism redirects the beam back through the crystal and the beam displacer. On the return path, the polarization beam displacer separates the elliptically polarized beam into two output beams of orthogonal linear polarization representing the major and minor axes. In crystals that introduce a phase differential attributable to temperature, a compensating crystal is provided to cancel the effect of temperature on the phase differential of the input beam. The system may include a detector for converting the output beams into electrical signals, and a signal processor for determining the voltage based on an analysis of the output beams. The output beams are amplitude modulated by the frequency of the electric field and the amplitude of the output beams is proportional to the magnitude of the electric field, which is related to the voltage being measured.

  7. Chapter 13 Employee Health and Safety 13.05 Abnormally Hazardous Tasks

    E-Print Network [OSTI]

    Sheridan, Jennifer

    Chapter 13 Employee Health and Safety 13.05 Abnormally Hazardous Tasks Form The Abnormally Hazardous Task Report Form http://oser.state.wi.us/docview.asp?docid=1116 is available to an employee who the "Abnormally Hazardous Task Report" shall review the situation with the employee and attempt to resolve

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

    E-Print Network [OSTI]

    Boyer, Edmond

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

  9. Voltage and frequency control of islanded microgrids: a plug-and-play approach

    E-Print Network [OSTI]

    Ferrari-Trecate, Giancarlo

    by microgrids that normally operate in grid-connected mode and that can be switched off- grid for guaranteeing

  10. Dynamic Voltage and Frequency Scaling: The Laws of Diminishing Returns Etienne Le Sueur and Gernot Heiser

    E-Print Network [OSTI]

    Heiser, Gernot

    on the older plat- forms, it actually increases energy usage on the most recent platform, even for highly- duces power consumption, which can lead to significant reduction in the energy required the potential energy savings resulting from DVFS. We analyse this trend by examining the potential of DVFS

  11. Dynamic Voltage and Frequency Scaling Control for Crossbars in Input-Queued Switches

    E-Print Network [OSTI]

    difficult to achieve. Reducing this thermal dissipation "bottleneck", or reducing the on-chip power the static power, due to leakage currents, since it tends to be proportional to the occupied area and can Abstract--The power consumption in chips, in general, and in crossbars switching fabrics, in particular

  12. CompilerDirected Dynamic Voltage/Frequency Scheduling for Energy Reduction in Microprocessors #

    E-Print Network [OSTI]

    Kremer, Ulrich

    consumption of a program. This paper discusses a com pilation strategy that identifies scaling opportunities of locality may be di#erent for di#erent program regions. Such computations may lead to a significant mismatch of the processor waiting for the memory subsystem to provide the data. Minimizing the power/energy dissipation

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

    E-Print Network [OSTI]

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

    2012-01-01T23:59:59.000Z

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

  14. Micro-grid operation of inverter based distributed generation with voltage and frequency dependent loads

    E-Print Network [OSTI]

    Zeineldin, H. H.

    Distribution systems are experiencing increasing penetration of distributed generation (DG). One attractive option is to use the available DG capacity during utility outages by forming planned micro-grids. Load sharing ...

  15. Instability of Wind Turbine Converters during Current Injection to Low Voltage Grid Faults and PLL Frequency

    E-Print Network [OSTI]

    Teodorescu, Remus

    , Omer; Aalborg University, Energy Technology Teodorescu, Remus; Aalborg University, Energy Technology Bak, Claus; Aalborg University, Energy Technology Iov, Florin; Aalborg University, Energy Technology. Göksu , R. Teodorescu, C. L. Bak and F. Iov are with the Department of Energy Technology, Aalborg

  16. Planar LTCC transformers for high voltage flyback converters.

    SciTech Connect (OSTI)

    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

    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.

  17. Enhanced sheath heating in capacitively coupled discharges due to non-sinusoidal voltage waveforms

    SciTech Connect (OSTI)

    Lafleur, T. [Johannesburg (South Africa); Boswell, R. W. [Space Plasma, Power and Propulsion Group, Research School of Physics and Engineering, Australian National University, Canberra ACT 0200 (Australia); Booth, J. P. [LPP-CNRS, Ecole Polytechnique, 91128 Palaiseau (France)

    2012-05-07T23:59:59.000Z

    Through the use of particle-in-cell simulations, we demonstrate that the power deposition in capacitively coupled discharges (in argon) can be increased by replacing sinusoidal waveforms with Gaussian-shaped voltage pulses (with a repetition frequency of 13.56 MHz). By changing the Gaussian pulse width, electron heating can be directly controlled, allowing for an increased plasma density and ion flux for the same gas pressure and geometrical operating conditions. Analysis of the power deposition profiles and electron distribution functions shows that enhanced electron-sheath heating is responsible for the increased power absorption.

  18. Low-profile high-voltage compact gas switch

    SciTech Connect (OSTI)

    Goerz, D.A.; Wilson, M.J.; Speer, R.D.

    1997-06-30T23:59:59.000Z

    This paper discusses the development and testing of a low-profile, high-voltage, spark-gap switch designed to be closely coupled with other components into an integrated high-energy pulsed-power source. The switch is designed to operate at 100 kV using SF6 gas pressurized to less than 0.7 MPa. The volume of the switch cavity region is less than 1.5 cm3, and the field stress along the gas-dielectric interface is as high as 130 kV/cm. The dielectric switch body has a low profile that is only I -cm tall at its greatest extent and nominally 2-mm thick over most of its area. This design achieves a very low inductance of less than 5 nH, but results in field stresses exceeding 500 kV/cm in the dielectric material. Field modeling was done to determine the appropriate shape for the highly stressed insulator and electrodes, and special manufacturing techniques were employed to mitigate the usual mechanisms that induce breakdown and failure in solid dielectrics. Static breakdown tests verified that the switch operates satisfactorily at 100 kV levels. The unit has been characterized with different shaped electrodes having nominal gap spacings of 2.0, 2.5, and 3.0 mm. The relationship between self-break voltage and operating pressure agrees well with published data on gas properties, accounting for the field enhancements of the electrode shapes being used. Capacitor discharge tests in a low inductance test fixture exhibited peak currents up to 25 kA with characteristic frequencies of the ringdown circuit ranging from 10 to 20 MHz. The ringdown waveforms and scaling of measured parameters agree well with circuit modeling of the switch and test fixture. Repetitive operation has been demonstrated at moderate rep-rates up to 15 Hz, limited by the power supply being used. Preliminary tests to evaluate lifetime of the compact switch assembly have been encouraging. In one case, after more than 7,000 high-current ringdown tests with approximately 30 C of total charge transferred, the switch continued to operate satisfactorily with no apparent tracking or deterioration of the insulator.

  19. Method for voltage-gated protein fractionation

    DOE Patents [OSTI]

    Hatch, Anson (Tracy, CA); Singh, Anup K. (Danville, CA)

    2012-04-24T23:59:59.000Z

    We report unique findings on the voltage dependence of protein exclusion from the pores of nanoporous polymer exclusion membranes. The pores are small enough that proteins are excluded from passage with low applied electric fields, but increasing the field enables proteins to pass through. The requisite field necessary for a change in exclusion is protein-specific with a correlation to protein size. The field-dependence of exclusion is important to consider for preconcentration applications. The ability to selectively gate proteins at exclusion membranes is also a promising means for manipulating and characterizing proteins. We show that field-gated exclusion can be used to selectively remove proteins from a mixture, or to selectively trap protein at one exclusion membrane in a series.

  20. Voltage controlled MESFET pulse shape generator

    SciTech Connect (OSTI)

    Burkhart, S.C.

    1994-10-26T23:59:59.000Z

    A programmable pulse shape generator capable of producing pulse shapes for Nova and Beamlet has been designed and simulated using the circuit code SPICE. The design utilizes power MESFETS, which are commonly used in microwave amplifiers. The pulse shape is varied by setting a bias voltage on each in a chain of MESFETS with a 200 ps temporal resolution. The electrical pulse then drives an integrated electro-optic modulator similar to what is on Beamlet. Pulse shapes 22 and 25, used on Nova, have been generated by this design. There is no fundamental barrier to making such a pulse generator for use on the National Ignition Facility. In fact, the longer time scales on the NIF pulse will ease the high speed requirements of the pulse shape generator allowing the use of less expensive components. The next step will be to build a prototype circuit for initial testing on Beamlet and Nova.

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

    Office of Scientific and Technical Information (OSTI)

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

  2. Mitigating Voltage Fade in Cathode Materials by Improving the...

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

    Fade in Cathode Materials by Improving the Atomic Level Uniformity of Elemental Distribution. Mitigating Voltage Fade in Cathode Materials by Improving the Atomic Level...

  3. Nanoscale Morphological and Chemical Changes of High Voltage...

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

    Nanoscale Morphological and Chemical Changes of High Voltage Lithium-Manganese Rich NMC Composite Cathodes with Cycling Friday, August 29, 2014 Renewable energy is critical for the...

  4. active capacitive voltage: Topics by E-print Network

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

    Khoman 5 Discrete Steps in the Capacitance-Voltage Characteristics of GaInNGaN Light Emitting Diode Structures Materials Science Websites Summary: Discrete Steps in the...

  5. Sharp interface and voltage conservation in the ... - Purdue University

    E-Print Network [OSTI]

    2007-07-14T23:59:59.000Z

    electrical wave is anisotropic, and cardiac tissue is made up of cells with heteroge- ... fact that voltage gain or loss due to numerical inaccuracies in the spatial...

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

    DOE Patents [OSTI]

    Su, Gui-Jia (Knoxville, TN)

    2008-08-05T23:59:59.000Z

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

  7. Electrochemical Characterization of Voltage Fade in LMR-NMC cells

    Broader source: Energy.gov (indexed) [DOE]

    the extent of Voltage Fade December 2012 * Establish baseline data on standard materials to facilitate comparison of various datasets March 2013 * Obtain data to determine...

  8. Electrochemical Characterization of Voltage Fade in LMR-NMC cells...

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

    Electrochemical Characterization of Voltage Fade in LMR-NMC cells 2013 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Program Annual Merit Review and Peer...

  9. Eastern Frequency Response Study

    SciTech Connect (OSTI)

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

    2013-05-01T23:59:59.000Z

    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.

  10. Method for sputtering with low frequency alternating current

    DOE Patents [OSTI]

    Timberlake, John R. (Allentown, NJ)

    1996-01-01T23:59:59.000Z

    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.

  11. Method for sputtering with low frequency alternating current

    DOE Patents [OSTI]

    Timberlake, J.R.

    1996-04-30T23:59:59.000Z

    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.

  12. Frequency selective infrared sensors

    SciTech Connect (OSTI)

    Davids, Paul; Peters, David W

    2014-11-25T23:59:59.000Z

    A frequency selective infrared (IR) photodetector having a predetermined frequency band. The exemplary frequency selective photodetector includes: a dielectric IR absorber having a first surface and a second surface substantially parallel to the first surface; an electrode electrically coupled to the first surface of the dielectric IR absorber; and a frequency selective surface plasmonic (FSSP) structure formed on the second surface of the dielectric IR absorber. The FSSP structure is designed to selectively transmit radiation in the predetermined frequency band that is incident on the FSSP structure substantially independent of the angle of incidence of the incident radiation on the FSSP structure.

  13. Frequency selective infrared sensors

    DOE Patents [OSTI]

    Davids, Paul; Peters, David W

    2013-05-28T23:59:59.000Z

    A frequency selective infrared (IR) photodetector having a predetermined frequency band. The exemplary frequency selective photodetector includes: a dielectric IR absorber having a first surface and a second surface substantially parallel to the first surface; an electrode electrically coupled to the first surface of the dielectric IR absorber; and a frequency selective surface plasmonic (FSSP) structure formed on the second surface of the dielectric IR absorber. The FSSP structure is designed to selectively transmit radiation in the predetermined frequency band that is incident on the FSSP structure substantially independent of the angle of incidence of the incident radiation on the FSSP structure.

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

    SciTech Connect (OSTI)

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

    2008-12-01T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

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

    2008-01-01T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

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

    2012-07-01T23:59:59.000Z

    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.

  17. Radio frequency detection assembly and method for detecting radio frequencies

    DOE Patents [OSTI]

    Cown, Steven H. (Rigby, ID); Derr, Kurt Warren (Idaho Falls, ID)

    2010-03-16T23:59:59.000Z

    A radio frequency detection assembly is described and which includes a radio frequency detector which detects a radio frequency emission produced by a radio frequency emitter from a given location which is remote relative to the radio frequency detector; a location assembly electrically coupled with the radio frequency detector and which is operable to estimate the location of the radio frequency emitter from the radio frequency emission which has been received; and a radio frequency transmitter electrically coupled with the radio frequency detector and the location assembly, and which transmits a radio frequency signal which reports the presence of the radio frequency emitter.

  18. Generation of a frequency comb and applications thereof

    SciTech Connect (OSTI)

    Hagmann, Mark J; Yarotski, Dmitry A

    2013-12-03T23:59:59.000Z

    Apparatus for generating a microwave frequency comb (MFC) in the DC tunneling current of a scanning tunneling microscope (STM) by fast optical rectification, cause by nonlinearity of the DC current vs. voltage curve for the tunneling junction, of regularly-spaced, short pulses of optical radiation from a focused mode-locked, ultrafast laser, directed onto the tunneling junction, is described. Application of the MFC to high resolution dopant profiling in semiconductors is simulated. Application of the MFC to other measurements is described.

  19. Appears in the Proceedings of the 47th Int'l Symp. on Microarchitecture (MICRO-47), December 2014 Enabling Realistic Fine-Grain Voltage Scaling with

    E-Print Network [OSTI]

    Batten, Christopher

    -level modeling to explore a new dynamic voltage/frequency scaling controller called the fine-grain synchronization controller (FG-SYNC+). FG-SYNC+ enables improved performance and energy efficiency at similar average power for multithreaded applications with activity im- balance. We then use circuit-level modeling

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

    SciTech Connect (OSTI)

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

    1996-08-01T23:59:59.000Z

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

  1. Measurement of high voltage using Rutherford backscattering spectrometry

    E-Print Network [OSTI]

    Abrego, Celestino Pete

    2007-04-25T23:59:59.000Z

    A novel variation of Rutherford Backscattering Spectrometry (RBS) has been utilized to measure a high voltage collected on an aluminum target by Direct Energy Conversion. The maximum high voltage on the target was measured to be 97.5 kV +/- 2 k...

  2. A LOW-VOLTAGE TEMPERATURE-STABLE MICROMECHANICAL PIEZOELECTRIC OSCILLATOR

    E-Print Network [OSTI]

    Ayazi, Farrokh

    A LOW-VOLTAGE TEMPERATURE-STABLE MICROMECHANICAL PIEZOELECTRIC OSCILLATOR Reza Abdolvand, Hossein polarization voltages (5-20V) for operation, which complicates the design of the oscillator circuit in today reference oscillator that utilizes a temperature-stable thin- film piezoelectric-on-silicon resonator

  3. Control and Protection Cooperation Strategy for Voltage Instability

    E-Print Network [OSTI]

    Chen, Zhe

    to be transmitted in the weak linked system. On the other hand, the backup protection relays on the transmissionControl and Protection Cooperation Strategy for Voltage Instability Zhou Liu Aalborg University zli are caused by unexpected backup relay operations due to low voltage or overload state caused by post fault

  4. Voltage sensor with fiber Fabry-Perot interferometer

    E-Print Network [OSTI]

    Wann, Been-Huey

    1992-01-01T23:59:59.000Z

    INTRODUCTION. Page II RESEARCH DESCRIPTION. . . A. Optical Fiber Fabry-Perot Interferometer. . . . . B. Piezoelectricity. . C. Modulating Point in 60 Hz Voltage Measurement. . . . . . D. Temperature Control Circuit . . . . 18 . . . 26 III EXPERIMENTAL... PROCEDURES AND RESULTS. . . . . . A. Fabrication of the Optical Fiber Fabry-Perot Interferometer B. Selection of Piezoelectric Materials. C. Implementation of Temperature Control Circuit. . . . D. Experiments of Optical Fiber Voltage Sensor...

  5. Analysis of Voltage Rise Effect on Distribution Network with Distributed

    E-Print Network [OSTI]

    Pota, Himanshu Roy

    Analysis of Voltage Rise Effect on Distribution Network with Distributed Generation M. A. Mahmud.hossain@adfa.edu.au, and H.Pota@adfa.edu.au). Abstract: Connections of distributed generation (DG) in distribution networks are increasing. These connections of distributed generation cause voltage rise in the distribution network

  6. CompilerDirected Dynamic Voltage Scaling Based on Program Regions

    E-Print Network [OSTI]

    Kremer, Ulrich

    CompilerDirected Dynamic Voltage Scaling Based on Program Regions ChungHsing Hsu and Ulrich using dynamic voltage scaling. The compiler identifies pro gram regions where the CPU can be slowed down without resulting in a significant overall performance loss. For such regions the lowest CPU

  7. Power Grid Voltage Integrity Verification Department of ECE

    E-Print Network [OSTI]

    Najm, Farid N.

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

  8. Radio frequency sheaths in an oblique magnetic field

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Myra, James R.; D'Ippolito, Daniel A.

    2015-06-01T23:59:59.000Z

    The physics of radio-frequency (rf) sheaths near a conducting surface is studied for plasmas immersed in a magnetic field that makes an oblique angle ? with the surface. A set of one-dimensional equations is developed that describe the dynamics of the time-dependent magnetic presheath and non-neutral Debye sheath. The model employs Maxwell-Boltzmann electrons, and the magnetization and mobility of the ions is determined by the magnetic field strength, and wave frequency, respectively. The angle, ? assumed to be large enough to insure an electron-poor sheath, is otherwise arbitrary. Concentrating on the ion-cyclotron range of frequencies, the equations are solved numericallymoreto obtain the rectified (dc) voltage, the rf voltage across the sheath and the rf current flowing through the sheath. As an application of this model, the sheath voltage-current relation is used to obtain the rf sheath impedance, which in turn gives an rf sheath boundary condition for the electric field at the sheath-plasma interface that can be used in rf wave codes. In general the impedance has both resistive and capacitive contributions, and generalizes previous sheath boundary condition models. The resistive part contributes to parasitic power dissipation at the wall.less

  9. Dynamic frequency tuning of electric and magnetic metamaterial response

    DOE Patents [OSTI]

    O'Hara, John F; Averitt, Richard; Padilla, Willie; Chen, Hou-Tong

    2014-09-16T23:59:59.000Z

    A geometrically modifiable resonator is comprised of a resonator disposed on a substrate, and a means for geometrically modifying the resonator. The geometrically modifiable resonator can achieve active optical and/or electronic control of the frequency response in metamaterials and/or frequency selective surfaces, potentially with sub-picosecond response times. Additionally, the methods taught here can be applied to discrete geometrically modifiable circuit components such as inductors and capacitors. Principally, controlled conductivity regions, using either reversible photodoping or voltage induced depletion activation, are used to modify the geometries of circuit components, thus allowing frequency tuning of resonators without otherwise affecting the bulk substrate electrical properties. The concept is valid over any frequency range in which metamaterials are designed to operate.

  10. Low-voltage gas-discharge device

    DOE Patents [OSTI]

    Kovarik, V.J.; Hershcovitch, A.; Prelec, K.

    1982-06-08T23:59:59.000Z

    An electronic device of the type wherein current flow is conducted by an ionized gas comprising a cathode of the type heated by ionic bombardment, an anode, means for maintaining a predetermined pressure in the region between the anode and the cathode and means for maintaining a field in the region is described. The field, which is preferably a combined magnetic and electric field, is oriented so that the mean distance traveled by electrons before reaching the anode is increased. Because of this increased distance traveled electrons moving to the anode will ionize a large number of gas atoms, thus reducing the voltage necessary to initiate gas breakdown. In a preferred embodiment the anode is a main hollow cathode and the cathode is a smaller igniter hollow cathode located within and coaxial with the main hollow cathode. An axial magnetic field is provided in the region between the hollow cathodes in order to facilitate gas breakdown in that region and initiate plasma discharge from the main hollow cathode.

  11. Spark-safe low-voltage detonator

    DOE Patents [OSTI]

    Lieberman, Morton L. (Albuquerque, NM)

    1989-01-01T23:59:59.000Z

    A column of explosive in a low-voltage detonator which makes it spark-safe ncludes an organic secondary explosive charge of HMX in the form of a thin pad disposed in a bore of a housing of the detonator in an ignition region of the explosive column and adjacent to an electrical ignition device at one end of the bore. The pad of secondary charge has an axial thickness within the range of twenty to thirty percent of its diameter. The explosive column also includes a first explosive charge of CP disposed in the housing bore in the ignition region of the explosive column next to the secondary charge pad on a side opposite from the ignition device. The first CP charge is loaded under sufficient pressure, 25 to 40 kpsi, to provide mechanical confinement of the pad of secondary charge and physical coupling thereof with the ignition device. The explosive column further includes a second explosive charge of CP disposed in the housing bore in a transition region of the explosive column next to the first CP charge on a side opposite from the pad of secondary charge. The second CP charge is loaded under sufficient pressure, about 10 kpsi, to allow occurrence of DDT. The first explosive CP charge has an axial thickness within the range of twenty to thirty percent of its diameter, whereas the second explosive CP charge contains a series of increments (nominally 4) each of which has an axial thickness-to-diameter ratio of one to two.

  12. Bonfire-safe low-voltage detonator

    DOE Patents [OSTI]

    Lieberman, Morton L. (Albuquerque, NM)

    1990-01-01T23:59:59.000Z

    A column of explosive in a low-voltage detonator which makes it bonfire-safe includes a first layer of an explosive charge of CP, or a primary explosive, and a second layer of a secondary organic explosive charge, such as PETN, which has a degradation temperature lower than the autoignition temperature of the CP or primary explosives. The first layer is composed of a pair of increments disposed in a bore of a housing of the detonator in an ignition region of the explosive column and adjacent to and in contact with an electrical ignition device at one end of the bore. The second layer is composed of a plurality of increments disposed in the housing bore in a transition region of the explosive column next to and in contact with the first layer on a side opposite from the ignition device. The first layer is loaded under a sufficient high pressure, 25 to 40 kpsi, to achieve ignition, whereas the second layer is loaded under a sufficient low pressure, about 10 kpsi, to allow occurrence of DDT. Each increment of the first and second layers has an axial length-to-diameter ratio of one-half.

  13. Bonfire-safe low-voltage detonator

    DOE Patents [OSTI]

    Lieberman, M.L.

    1988-07-01T23:59:59.000Z

    A column of explosive in a low-voltage detonator which makes it bonfire-safe includes a first layer of an explosive charge of CP, or a primary explosive, and a second layer of a secondary organic explosive charge, such as PETN, which has a degradation temperature lower than the autoignition temperature of the CP or primary explosives. The first layer is composed of a pair of increments disposed in a bore of a housing of the detonator in an ignition region of the explosive column and adjacent to and in contact with an electrical ignition device at one end of the bore. The second layer is composed of a plurality of increments disposed in the housing bore in a transition region of the explosive column next to and in contact with the first layer on a side opposite from the ignition device. The first layer is loaded under a sufficient high pressure, 25 to 40 kpsi, to achieve ignition, whereas the second layer is loaded under a sufficient low pressure, about 10 kpsi, to allow occurrence of DDT. Each increment of the first and second layers has an axial length-to-diameter ratio of one-half. 2 figs.

  14. Very Low Frequency Breakdown Strengths of Electrical Insulation Materials at Cryogenic Temperatures

    SciTech Connect (OSTI)

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

    2009-01-01T23:59:59.000Z

    For long cables or equipment with large capacitance it is not always possible to conduct high voltage withstand 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), 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 voltage stress time 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.

  15. Frequency Response Analysis Tool

    SciTech Connect (OSTI)

    Etingov, Pavel V.; Kosterev, Dmitry; Dai, T.

    2014-12-31T23:59:59.000Z

    Frequency response has received a lot of attention in recent years at the national level, which culminated in the development and approval of North American Electricity Reliability Corporation (NERC) BAL-003-1 Frequency Response and Frequency Bias Setting Reliability Standard. This report is prepared to describe the details of the work conducted by Pacific Northwest National Laboratory (PNNL) in collaboration with the Bonneville Power Administration and Western Electricity Coordinating Council (WECC) Joint Synchronized Information Subcommittee (JSIS) to develop a frequency response analysis tool (FRAT). The document provides the details on the methodology and main features of the FRAT. The tool manages the database of under-frequency events and calculates the frequency response baseline. Frequency response calculations are consistent with frequency response measure (FRM) in NERC BAL-003-1 for an interconnection and balancing authority. The FRAT can use both phasor measurement unit (PMU) data, where available, and supervisory control and data acquisition (SCADA) data. The tool is also capable of automatically generating NERC Frequency Response Survey (FRS) forms required by BAL-003-1 Standard.

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

    E-Print Network [OSTI]

    Cañizares, Claudio A.

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

  17. Self-excited nonlinear plasma series resonance oscillations in geometrically symmetric capacitively coupled radio frequency discharges

    SciTech Connect (OSTI)

    Donko, Z. [Research Institute for Solid State Physics and Optics, Hungarian Academy of Sciences, P.O. Box 49, H-1525 Budapest (Hungary); Schulze, J.; Czarnetzki, U.; Luggenhoelscher, D. [Institute for Plasma and Atomic Physics, Ruhr-University Bochum, Bochum 44780 (Germany)

    2009-03-30T23:59:59.000Z

    At low pressures, nonlinear self-excited plasma series resonance (PSR) oscillations are known to drastically enhance electron heating in geometrically asymmetric capacitively coupled radio frequency discharges by nonlinear electron resonance heating (NERH). Here we demonstrate via particle-in-cell simulations that high-frequency PSR oscillations can also be excited in geometrically symmetric discharges if the driving voltage waveform makes the discharge electrically asymmetric. This can be achieved by a dual-frequency (f+2f) excitation, when PSR oscillations and NERH are turned on and off depending on the electrical discharge asymmetry, controlled by the phase difference of the driving frequencies.

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

    SciTech Connect (OSTI)

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

    1996-12-31T23:59:59.000Z

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

  19. Electro-optic voltage sensor with beam splitting

    DOE Patents [OSTI]

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

    2002-01-01T23:59:59.000Z

    The invention is a miniature electro-optic voltage sensor system capable of accurate operation at high voltages without use of the dedicated voltage dividing hardware typically found in the prior art. The invention achieves voltage measurement without significant error contributions from neighboring conductors or environmental perturbations. The invention employs a transmitter, a sensor, a detector, and a signal processor. The transmitter produces a beam of electromagnetic radiation which is routed into the sensor. Within the sensor the beam undergoes the Pockels electro-optic effect. The electro-optic effect produces a modulation of the beam's polarization, which is in turn converted to a pair of independent conversely-amplitude-modulated signals, from which the voltage of the E-field is determined by the signal processor. The use of converse AM signals enables the signal processor to better distinguish signal from noise. The sensor converts the beam by splitting the beam in accordance with the axes of the beam's polarization state (an ellipse) into at least two AM signals. These AM signals are fed into a signal processor and processed to determine the voltage between a ground conductor and the conductor on which voltage is being measured.

  20. Electro-optic voltage sensor with Multiple Beam Splitting

    DOE Patents [OSTI]

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

    2000-01-01T23:59:59.000Z

    A miniature electro-optic voltage sensor system capable of accurate operation at high voltages without use of the dedicated voltage dividing hardware. The invention achieves voltage measurement without significant error contributions from neighboring conductors or environmental perturbations. The invention employs a transmitter, a sensor, a detector, and a signal processor. The transmitter produces a beam of electromagnetic radiation which is routed into the sensor. Within the sensor the beam undergoes the Pockels electro-optic effect. The electro-optic effect produces a modulation of the beam's polarization, which is in turn converted to a pair of independent conversely-amplitude-modulated signals, from which the voltage of the E-field is determined by the signal processor. The use of converse AM signals enables the signal processor to better distinguish signal from noise. The sensor converts the beam by splitting the beam in accordance with the axes of the beam's polarization state (an ellipse) into at least two AM signals. These AM signals are fed into a signal processor and processed to determine the voltage between a ground conductor and the conductor on which voltage is being measured.

  1. Spark-safe low-voltage detonator

    DOE Patents [OSTI]

    Lieberman, M.L.

    1988-07-01T23:59:59.000Z

    A column of explosive in a low-voltage detonator which makes it spark-safe includes an organic secondary explosive charge of HMX in the form of a thin pad disposed in a bore of a housing of the detonator in an ignition region of the explosive column and adjacent to an electrical ignition device at one end of the bore. The pad of secondary charge has an axial thickness within the range of twenty to thirty percent of its diameter. The explosive column also includes a first explosive charge of CP disposed in the housing bore in the ignition region of the explosive column next to the secondary charge pad on a side opposite from the ignition device. The first CP charge is loaded under sufficient pressure, 25 to 40 kpsi, to provide mechanical confinement of the pad of secondary charge and physical coupling thereof with the ignition device. The explosive column further includes a second explosive charge of CP disposed in the housing bore in a transition region of the explosive column next to the first CP charge on a side opposite from the pad of secondary charge. The second CP charge is loaded under sufficient pressure, about 10 kpsi, to allow occurrence of DDT. The first explosive CP charge has an axial thickness within the range of twenty to thirty percent of its diameter, whereas the second explosive CP charge contains a series of increments (nominally 4), each of which has an axial thickness-to-diameter ratio of one to two. 2 figs.

  2. acid-induced abnormal behavior: Topics by E-print Network

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

    reprint requests to: Sonja Sonja Lyubomirsky; Lorie Sousa; Regina C. Casper 27 Is Dark Energy Abnormally Weighting? Astrophysics (arXiv) Summary: We present a new interpretation of...

  3. Stabilized radio frequency quadrupole

    DOE Patents [OSTI]

    Lancaster, Henry D. (Orinda, CA); Fugitt, Jock A. (Berkeley, CA); Howard, Donald R. (Danville, CA)

    1984-01-01T23:59:59.000Z

    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.

  4. Microfabricated ion frequency standard

    SciTech Connect (OSTI)

    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

    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.

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

    DOE Patents [OSTI]

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

    1993-01-19T23:59:59.000Z

    An optically triggered solid state switch and method for switching a high voltage electrical current. A plurality of solid state switches (350) are connected in series for controlling electrical current flow between a compensation capacitor (112) and ground in a reactive power compensator (50, 50') that monitors the voltage and current flowing through each of three distribution lines (52a, 52b and 52c), which are supplying three-phase power to one or more inductive loads. An optical transmitter (100) controlled by the reactive power compensation system produces light pulses that are conveyed over optical fibers (102) to a switch driver (110') that includes a plurality of series connected optical triger circuits (288). Each of the optical trigger circuits controls a pair of the solid state switches and includes a plurality of series connected resistors (294, 326, 330, and 334) that equalize or balance the potential across the plurality of trigger circuits. The trigger circuits are connected to one of the distribution lines through a trigger capacitor (340). In each switch driver, the light signals activate a phototransistor (300) so that an electrical current flows from one of the energy reservoir capacitors through a pulse transformer (306) in the trigger circuit, producing gate signals that turn on the pair of serially connected solid state switches (350).

  6. Secondary Control for Voltage Unbalance Compensation in an Islanded Microgrid

    E-Print Network [OSTI]

    Vasquez, Juan Carlos

    coupling (PCC). Unbalance compensation is achieved by proper control of distributed generators (DGs unbalance. Keywords-distributed generation; microgrid; secondary control; voltage unbalance compensation I. INTRODUCTION Distributed Generators (DGs) may be connected individually to the utility grid or be integrated

  7. Time varying voltage combustion control and diagnostics sensor

    DOE Patents [OSTI]

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

    2011-04-19T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

    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

    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.

  9. An Adaptive Voltage Control Algorithm with Multiple Distributed Energy

    SciTech Connect (OSTI)

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

    2009-01-01T23:59:59.000Z

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

  10. Operation of buck regulator with ultra-low input voltage

    E-Print Network [OSTI]

    Harris, Cory Angelo

    2014-01-01T23:59:59.000Z

    Based on the LTC3621 and LTC3624, the designed buck regulator proposed in this thesis aims to lower the allowed input voltage and increase efficiency compared to the original part without making significant changes to ...

  11. Multilevel cascade voltage source inverter with seperate DC sources

    DOE Patents [OSTI]

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

    2002-01-01T23:59:59.000Z

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

  12. High-voltage air-core pulse transformers

    SciTech Connect (OSTI)

    Rohwein, G. J.

    1981-01-01T23:59:59.000Z

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

  13. IEEE 342 Node Low Voltage Networked Test System

    SciTech Connect (OSTI)

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

    2014-07-31T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

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

    2012-09-05T23:59:59.000Z

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

  15. Unravelling the Performance Degradation Mechanisms in High-voltage...

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

    Unravelling the Performance Degradation Mechanisms in High-voltage Lithium-ion Battery Composite Oxide Electrodes Apr 11 2014 02:00 PM - 03:00 PM Debasish Mohanty, ORNL, Oak Ridge...

  16. Voltage Dependent Charge Storage Modes and Capacity in Subnanometer Pores

    SciTech Connect (OSTI)

    Qiao, Rui [Clemson University; Meunier, V. [Rensselaer Polytechnic Institute (RPI); Huang, Jingsong [ORNL; Wu, Peng [ORNL; Sumpter, Bobby G [ORNL

    2012-01-01T23:59:59.000Z

    Using molecular dynamics simulations, we show that charge storage in subnanometer pores follows a distinct voltage-dependent behavior. Specifically, at lower voltages, charge storage is achieved by swapping co-ions in the pore with counterions in the bulk electrolyte. As voltage increases, further charge storage is due mainly to the removal of co-ions from the pore, leading to a capacitance increase. The capacitance eventually reaches a maximum when all co-ions are expelled from the pore. At even higher electrode voltages, additional charge storage is realized by counterion insertion into the pore, accompanied by a reduction of capacitance. The molecular mechanisms of these observations are elucidated and provide useful insight for optimizing energy storage based on supercapacitors.

  17. Modeling the operating voltage of liquid metal battery cells

    E-Print Network [OSTI]

    Newhouse, Jocelyn Marie

    2014-01-01T23:59:59.000Z

    A one-dimensional, integrative model of the voltage during liquid metal battery operation has been developed to enhance the understanding of performance at the cell level. Two liquid metal batteries were studied: Mg-Sb for ...

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

    E-Print Network [OSTI]

    Esquit Hernandez, Carlos A.

    2010-01-16T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Esquit Hernandez, Carlos A.

    2010-01-16T23:59:59.000Z

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

  20. Multilevel cascade voltage source inverter with seperate DC sources

    DOE Patents [OSTI]

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

    1997-01-01T23:59:59.000Z

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

  1. Multilevel cascade voltage source inverter with seperate DC sources

    DOE Patents [OSTI]

    Peng, Fang Zheng; Lai, Jih-Sheng

    2001-04-03T23:59:59.000Z

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

  2. Multilevel cascade voltage source inverter with separate DC sources

    DOE Patents [OSTI]

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

    1997-06-24T23:59:59.000Z

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

  3. Prediction of flashover voltage of non-ceramic insulators under contaminated conditions

    E-Print Network [OSTI]

    Prediction of flashover voltage of non-ceramic insulators under contaminated conditions S ABSTRACT This paper describes the development of a theoretical model to predict flashover voltage

  4. Measuring Helical FCG Voltage with an Electric Field Antenna

    SciTech Connect (OSTI)

    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

    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.

  5. Image-line voltage controlled oscillators and grating antennas

    E-Print Network [OSTI]

    Kirk, Alexander MacDonald

    1991-01-01T23:59:59.000Z

    IMAGE-LINE VOLTAGE CONTROLLED OSCILLATORS AND GRATING ANTENNAS A Thesis by ALEXANDER MacDONALD KIRK Submitted to the Office of Graduate Studies of Texas ABM University in partial fulfillment of the requirements for the degree of MASTER... OF SCIENCE May 1991 Major Subject: Electrical Engineering IMAGE-LINE VOLTAGE CONTROLLED OSCILLATORS AND GRATING ANTENNAS A Thesis by ALEXANDER MacDONALD KIRK Approved as to style and content by: Kai Chang (Chair of Committee) Robert D. Nevels...

  6. Sinusoidal voltage controlled oscillators using operational transconductance amplifiers

    E-Print Network [OSTI]

    Hoyle Passano, Javier Joaquin

    1985-01-01T23:59:59.000Z

    SINUSOIDAI. VOLTAGE CONTROLLED OSCILLATORS I. SING OPERATIONAL TRANSCONDUCTANCE AMPLIFIERS A Thesis JAVIFB . IOAQUIN HOYI. K I'ASSANO Suhndtted to the Graduate College ol' 'I'exes A8cM University in partial fulfillment of the requirement... for the degree of MASTER OF SCIENCE May 1985 Major Subject: Electrical Engineering SINUSOIDAL VOLTAGE CONTROLLED OSCILLATORS USING OPERATIONAI, TRANSCONDUCTANCE AMPLIFIERS A Thesis by JAVIER JOAQUIN HOYLE PASSANO Approved as to style and content by: o...

  7. Chloromethyl chlorosulfate as a voltage delay inhibitor in lithium cells

    DOE Patents [OSTI]

    Delnick, F.M.

    1993-04-13T23:59:59.000Z

    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.

  8. Chloromethyl chlorosulfate as a voltage delay inhibitor in lithium cells

    DOE Patents [OSTI]

    Delnick, Frank M. (Albuquerque, NM)

    1993-01-01T23:59:59.000Z

    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.

  9. Aalborg Universitet Frequency Stability of Hierarchically Controlled Hybrid Photovoltaic-Battery-

    E-Print Network [OSTI]

    Vasquez, Juan Carlos

    sharing among PV voltage source inverters (VSIs), while injecting the dispatched power to the main grid as well. However, the different resources with conventional constant P/Q and P/V controls coexisting. Further, frequency stability analysis is presented based on small signal models of the hybrid PV

  10. Bandwidth scaling and spectral flatness enhancement of optical frequency combs from phase-modulated

    E-Print Network [OSTI]

    Purdue University

    linearly with the RF voltage driving the phase modulator. RF power handling limits the number of lines.g., 200 GHz band- width at 10 GHz drive). To reach the 100 line level, we would have to cascade five a 10 GHz frequency comb with over 100 lines in a 10 dB bandwidth in which a record 75 lines are within

  11. eta Chameleontis: abnormal initial mass function or dynamical evolution?

    E-Print Network [OSTI]

    E. Moraux; W. Lawson; C. Clarke

    2007-07-15T23:59:59.000Z

    Eta Chamaeleontis is a unique young (~9 Myr) association with 18 systems concentrated in a radius of ~35 arcmin, i.e. 1pc at the cluster distance of 97pc. No other members have been found up to 1.5 degrees from the cluster centre. The cluster mass function is consistent with the IMF of other rich young open clusters in the higher mass range but shows a clear deficit of low mass stars and brown dwarfs with no objects below 0.1Msun. The aim of this paper is to test whether this peculiar mass function could result from dynamical evolution despite the young age of the cluster. We performed N-body numerical calculations starting with a log-normal IMF and different initial conditions in terms of number of systems and cluster radius using the code NBODY3. We simulated the cluster dynamical evolution over 10 Myr and compared the results to the observations. We found that it is possible to reproduce eta Cha when starting with a very compact configuration (with Ninit=40 and R0=0.005pc) which suggests that the IMF of the association might not be abnormal. The high initial density might also explain the deficit of wide binaries that is observed in the cluster.

  12. Viscoelastic effects on frequency tuning of a dielectric elastomer membrane resonator

    SciTech Connect (OSTI)

    Zhou, Jianyou; Jiang, Liying, E-mail: lyjiang@eng.uwo.ca; Khayat, Roger E. [Department of Mechanical and Materials Engineering, The University of Western Ontario, London, Ontario N6A 5B9 (Canada)

    2014-03-28T23:59:59.000Z

    As a recent application of dielectric elastomers (DEs), DE resonators have become an alternative to conventional silicon-based resonators used in MEMS and have attracted much interest from the research community. However, most existing modeling works for the DE resonators ignore the intrinsic viscoelastic effect of the material that may strongly influence their dynamic performance. Based on the finite-deformation viscoelasticity theory for dielectrics, this paper theoretically examines the in-plane oscillation of a DE membrane resonator to demonstrate how the material viscoelasticity affects the actuation and frequency tuning processes of the resonator. From the simulation results, it is concluded that not only the applied voltage can change the natural frequency of the resonator, but also the inelastic deformation contributes to frequency tuning. Due to the viscoelasticity of the material, the electrical loading rate influences the actuation process of the DE resonator, while it has little effect on the final steady frequency tuned by the prescribed voltage within the safety range. With the consideration of the typical failure modes of the resonator and the evolution process of the material, the tunable frequency range and the safe range of the applied voltage of the DE membrane resonator with different dimension parameters are determined in this work, which are found to be dependent on the electrical loading rate. This work is expected to provide a better understanding on the frequency tuning of viscoelastic DE membrane resonators and a guideline for the design of DE devices.

  13. 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

  14. Graphene Frequency Multipliers

    E-Print Network [OSTI]

    Wang, Han

    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 ...

  15. Variable Frequency Pump Drives

    E-Print Network [OSTI]

    Karassik, I. J.; Petraccaro, L. L.; McGuire, J. T.

    . In a conventional pump and driver arrangement (for example, a centrifugal pump coupled to an AC induction motor'with no speed control provision), the motor runs at. a constant speed, which is determined by the incoming line frequency, and the pump... when it is needed. LONG RANGE DESIGN TRENDS The growing use of variable-frequency electric motor drives will permit the integration of 60 and 50 cycle pump lines. One important concern for future improvements is the growing possibility...

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

    E-Print Network [OSTI]

    Anders, Andre; Andersson, Joakim; Ehiasarian, Arutiun

    2008-01-01T23:59:59.000Z

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

  17. Simulated combined abnormal environment fire calculations for aviation impacts.

    SciTech Connect (OSTI)

    Brown, Alexander L.

    2010-08-01T23:59:59.000Z

    Aircraft impacts at flight speeds are relevant environments for aircraft safety studies. This type of environment pertains to normal environments such as wildlife impacts and rough landings, but also the abnormal environment that has more recently been evidenced in cases such as the Pentagon and World Trade Center events of September 11, 2001, and the FBI building impact in Austin. For more severe impacts, the environment is combined because it involves not just the structural mechanics, but also the release of the fuel and the subsequent fire. Impacts normally last on the order of milliseconds to seconds, whereas the fire dynamics may last for minutes to hours, or longer. This presents a serious challenge for physical models that employ discrete time stepping to model the dynamics with accuracy. Another challenge is that the capabilities to model the fire and structural impact are seldom found in a common simulation tool. Sandia National Labs maintains two codes under a common architecture that have been used to model the dynamics of aircraft impact and fire scenarios. Only recently have these codes been coupled directly to provide a fire prediction that is better informed on the basis of a detailed structural calculation. To enable this technology, several facilitating models are necessary, as is a methodology for determining and executing the transfer of information from the structural code to the fire code. A methodology has been developed and implemented. Previous test programs at the Sandia National Labs sled track provide unique data for the dynamic response of an aluminum tank of liquid water impacting a barricade at flight speeds. These data are used to validate the modeling effort, and suggest reasonable accuracy for the dispersion of a non-combustible fluid in an impact environment. The capability is also demonstrated with a notional impact of a fuel-filled container at flight speed. Both of these scenarios are used to evaluate numeric approximations, and help provide an understanding of the quantitative accuracy of the modeling methods.

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

    E-Print Network [OSTI]

    Rami Amro; Alexander B. Neiman

    2012-09-27T23:59:59.000Z

    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.

  19. Concept of Quasi-Capacitive Tapping of Bipolar Voltage-Controlled Oscillators

    E-Print Network [OSTI]

    Serdijn, Wouter A.

    Concept of Quasi-Capacitive Tapping of Bipolar Voltage-Controlled Oscillators Aleksandar Tasic the active part of the oscillator and the LC-tank, as proposed in this paper, the voltage swing over the tank of high- performance bipolar voltage-controlled oscillators (VCO's). As the voltage-controlled oscillators

  20. Neurocomputing 69 (2006) 10621065 Dependence of the spike-triggered average voltage on

    E-Print Network [OSTI]

    Gerstner, Wulfram

    2006-01-01T23:59:59.000Z

    .V. All rights reserved. Keywords: Spike-triggered voltage; h-current; Damped voltage oscillations 1 oscillations. The model comprises a variable v for the membrane voltage, with time-scale tv and a secondNeurocomputing 69 (2006) 10621065 Dependence of the spike-triggered average voltage on membrane

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

    SciTech Connect (OSTI)

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

    2011-02-01T23:59:59.000Z

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

  2. DATE04 SPECIAL SECTION Overhead-conscious voltage selection for dynamic

    E-Print Network [OSTI]

    Marchal, Loris

    combination with dynamic voltage scaling indispensable for energy-efficient designs in the foreseeable future

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

    DOE Patents [OSTI]

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

    1994-09-13T23:59:59.000Z

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

  4. Voltage sensing in ion channels: Mesoscale simulations of biological devices

    E-Print Network [OSTI]

    Peyser, Alexander

    2012-01-01T23:59:59.000Z

    Electrical signaling via voltage-gated ion channels depends upon the function of a voltage sensor (VS), identified with the S1-S4 domain in voltage-gated K+ channels. Here we investigate some energetic aspects of the sliding-helix model of the VS using simulations based on VS charges, linear dielectrics and whole-body motion. Model electrostatics in voltage-clamped boundary conditions are solved using a boundary element method. The statistical mechanical consequences of the electrostatic configurational energy are computed to gain insight into the sliding-helix mechanism and to predict experimentally measured ensemble properties such as gating charge displaced by an applied voltage. Those consequences and ensemble properties are investigated for two alternate S4 configurations, \\alpha- and 3(10)-helical. Both forms of VS are found to have an inherent electrostatic stability. Maximal charge displacement is limited by geometry, specifically the range of movement where S4 charges and counter-charges overlap in t...

  5. Unified model of voltage/current mode control to predict subharmonic oscillation

    E-Print Network [OSTI]

    Fang, Chung-Chieh

    2012-01-01T23:59:59.000Z

    A unified model of voltage mode control (VMC) and current mode control (CMC) is proposed to predict the subharmonic oscillation. In the unified model, based on the sampled-data slope-based analysis, the subharmonic oscillation boundary conditions for VMC/CMC have similar forms. The boundary conditions are exact, and can be further simplified in various approximate closed forms for design purpose. Harmonic balance analysis is also applied. Both the slope-based and harmonic balance analysis are applied to analyze five different VMC/CMC control schemes. A new "HB plot" and an equivalent "M plot" are proposed to accurately predict the subharmonic oscillation. The relation between the crossover frequency and the subharmonic oscillation is also analyzed.

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

    SciTech Connect (OSTI)

    Sauers, I.; Tuncer, E.; Polizos, G.; James, D. R.; Ellis, A. R.; Pace, M. O. [Applied Superconductivity Group, Fusion Energy Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States)

    2010-04-08T23:59:59.000Z

    For long cables or equipment with large capacitance it is not always possible to conduct high voltage withstand 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.

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

    SciTech Connect (OSTI)

    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

    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.

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

    SciTech Connect (OSTI)

    Sauers, I. [Oak Ridge National Laboratory (ORNL); Tuncer, E. [Oak Ridge National Laboratory (ORNL); Polizos, G. [Oak Ridge National Laboratory (ORNL); James, D. R. [Oak Ridge National Laboratory (ORNL); Ellis, A. R. [Oak Ridge National Laboratory (ORNL); Pace, M. O. [Oak Ridge National Laboratory (ORNL)

    2010-01-01T23:59:59.000Z

    For long cables or equipment with large capacitance it is not always possible to conduct high voltage withstand 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 G 10 (fiberglass reinforced plastic or FRP), Cryoflex (TM) (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 I 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.

  9. Chapter 18: Variable Frequency Drive Evaluation Protocol

    SciTech Connect (OSTI)

    Romberger, J.

    2014-11-01T23:59:59.000Z

    An adjustable-speed drive (ASD) includes all devices that vary the speed of a rotating load, including those that vary the motor speed and linkage devices that allow constant motor speed while varying the load speed. The Variable Frequency Drive Evaluation Protocol presented here addresses evaluation issues for variable-frequency drives (VFDs) installed on commercial and industrial motor-driven centrifugal fans and pumps for which torque varies with speed. Constant torque load applications, such as those for positive displacement pumps, are not covered by this protocol. Other ASD devices, such as magnetic drive, eddy current drives, variable belt sheave drives, or direct current motor variable voltage drives, are also not addressed. The VFD is by far the most common type of ASD hardware. With VFD speed control on a centrifugal fan or pump motor, energy use follows the affinity laws, which state that the motor electricity demand is a cubic relationship to speed under ideal conditions. Therefore, if the motor runs at 75% speed, the motor demand will ideally be reduced to 42% of full load power; however, with other losses it is about 49% of full load power.

  10. Electrical laser frequency tuning by three terminal terahertz quantum cascade lasers

    SciTech Connect (OSTI)

    Ohtani, K., E-mail: otanik@phys.ethz.ch; Beck, M.; Faist, J., E-mail: jerome.faist@phys.ethz.ch [Institute for Quantum Electronics, ETH Zurich, Wolfgang-Pauli Str. 16, 8093 Zurich (Switzerland)

    2014-01-06T23:59:59.000Z

    Electrical laser emission frequency tuning of a three terminal THz quantum cascade laser is demonstrated. A high electron mobility transistor structure is used in a surface plasmon waveguide to modulate the electron density in a channel, controlling the effective refractive index of the waveguide. The threshold current density was modulated by 28% via applying voltage from ?3 to 2?V. The observed laser emission frequency shift by electric field was 2?GHz. By using the three terminal devices, pure frequency modulation of the output light is, in principle, achievable.

  11. High voltage stability performance of a gamma ray detection device

    SciTech Connect (OSTI)

    Abdullah, Nor Arymaswati; Lombigit, Lojius; Rahman, Nur Aira Abd [Technical Support Division, Malaysian Nuclear Agency, 43000 Kajang, Selangor (Malaysia)

    2014-02-12T23:59:59.000Z

    An industrial grade digital radiation survey meter device is currently being developed at Malaysian Nuclear Agency. This device used a cylindrical type Geiger Mueller (GM) which acts as a detector. GM detector operates at relatively high direct current voltages depend on the type of GM tube. This thin/thick walled cylindrical type of GM tube operates at 450-650 volts range. Proper value and stability performance of high voltage are important parameters to ensure that this device give a reliable radiation dose measurement. This paper will present an assessment of the stability and performance of the high voltage supply for radiation detector. The assessment is performed using System Identification tools box in MATLAB and mathematical statistics.

  12. Voltage Impacts of Utility-Scale Distributed Wind

    SciTech Connect (OSTI)

    Allen, A.

    2014-09-01T23:59:59.000Z

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

  13. A study of temperature compensating circuits for voltage references which use negative temperature coefficient zener diodes

    E-Print Network [OSTI]

    Coleman, Spencer Delano

    1961-01-01T23:59:59.000Z

    Character- istics in Breakdown Region . 13 3f. 1N 751 Zener Diode Voltage vs Current Character- istics in Breakdown Region . 14 3g, lN752 Zener Diode Voltage vs Current Character- istics in Breakdown Region 15 4a. 1N746 Zener Diode Ambient Temperature... vs Voltage Characteristics in Breakdown Region. . . . . . . . . . 16 4b. IN747 Zener Diode Ambient Temperature vs Voltage Characteristics in Breakdown Region. . . . . . . . . . 17 4c. 1N748 Zener Diode Ambient Temperature vs Voltage...

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

    E-Print Network [OSTI]

    Kioussis, Nicholas

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

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

    E-Print Network [OSTI]

    Serdijn, Wouter A.

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

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

    DOE Patents [OSTI]

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

    2013-01-08T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

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

    2011-10-10T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

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

    1994-02-01T23:59:59.000Z

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

  19. Radio-frequency probes of Antarctic ice at South Pole

    E-Print Network [OSTI]

    Besson, David Zeke; Kravchenko, I.

    2013-05-16T23:59:59.000Z

    the 1 1.5 2 2.5 3 3.5 4 0 200 400 600 800 1000 1200 1400 VS WR Frequency (MHz) Horn VSWR Tx SWRRx SWR Fig. 1. Voltage Standing Wave Ratio (VSWR) for both transmitter (Tx) and receiver (Rx) horn used for data taken at South Pole. signal... produce an azimuthal variation in echo strength. The Fresnel zone has a radial extent R roughly given by R ? ? 2?dTxdRx/(dTx + dRx)/2; using ??1 m and dTx ? dRx ?1000 m, we find R ?30 m. Nanosecond scale in- terference effects (the maximum allowed by Fig...

  20. Frequency Control Performance Measurement and Requirements

    E-Print Network [OSTI]

    Illian, Howard F.

    2011-01-01T23:59:59.000Z

    DCS only measured low-frequency disturbances instead of bothlow- and high-frequency disturbances. The DCS requiredof the pre-disturbance frequency and the settling frequency.

  1. APPENDIX 13-C Abnormally Hazardous Task Report DER-DCLR-33.

    E-Print Network [OSTI]

    Sheridan, Jennifer

    APPENDIX 13-C Abnormally Hazardous Task Report DER-DCLR-33. EMPLOYING UNIT CONTACT PERSON Academic Technology--Printing Areas Geoff Larson, 212 Env Protection-Safefty Bldg 263-9002 All Others Areas Tom Rutlin

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

    E-Print Network [OSTI]

    Krebsbach, Kurt D.

    Automated Reasoning Group Honeywell Technology Center 3660 Technology Drive Minneapolis, MN 55418 fkrebsbac,muslinerg@htc.honeywell, estimating (abnormal) states, and diagnosing, isolating, and recovering from mal- functions. At the Honeywell

  3. Abnormal Acidification of Melanoma Cells Induces Tyrosinase Retention in the Early Secretory Pathway*

    E-Print Network [OSTI]

    Hebert, Daniel N.

    Abnormal Acidification of Melanoma Cells Induces Tyrosinase Retention in the Early Secretory, Pennsylvania 19107 In tyrosinase-positive amelanotic melanoma cells, in- active tyrosinase accumulates-ATPase)-mediated proton transport in melanoma cells disrupts tyrosinase trafficking through the secretory pathway

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

    E-Print Network [OSTI]

    Leuciuc, Adrian

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

  5. The probable source of certain spurious frequencies found in the output of a variable speed generating system using slip recovery

    SciTech Connect (OSTI)

    Carlin, P.W.

    1989-06-01T23:59:59.000Z

    As part of US Department of Energy-sponsored research on wind energy, a Mod-O wind turbine was used to drive a variable-speed, wound-rotor, induction generator. Energy resulting from the slip frequency voltage in the generator rotor was rectified to dc, inverted back to utility frequency ac, and injected into the power line. Spurious changing frequencies displayed in the generator output by a spectrum analyzer are caused by ripple on the dc link. No resonances of any of these moving frequencies were seen in spite of the presence of a bank of power factor correcting capacitors. 5 figs.

  6. Way to reduce arc voltage losses in hybrid thermionic converters

    SciTech Connect (OSTI)

    Tskhakaya, V.K.; Yarygin, V.I.

    1982-03-01T23:59:59.000Z

    Experimental results are reported concerning the output and emission characteristics of the arc and hybrid regimes in a plane-parallel thermionic converter with Pt--Zr--O electrode pair. It is shown that arc voltage losses can be reduced to values below those obtainable in ordinary arc thermionic converters.

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

    E-Print Network [OSTI]

    Calhoun, Benton H.

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

  8. Current isolating epitaxial buffer layers for high voltage photodiode array

    DOE Patents [OSTI]

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

    2002-01-01T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    Wichmann, Felix

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

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

    E-Print Network [OSTI]

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

  11. Enhanced Archaerhodopsin Fluorescent Protein Voltage Yiyang Gong1,2*

    E-Print Network [OSTI]

    Ferrari, Silvia

    Enhanced Archaerhodopsin Fluorescent Protein Voltage Indicators Yiyang Gong1,2* , Jin Zhong Li1 by nearly three-fold in comparison to Arch-D95N. Citation: Gong Y, Li JZ, Schnitzer MJ (2013) Enhanced; Published June 19, 2013 Copyright: 2013 Gong et al. This is an open-access article distributed under

  12. Topical Review Voltage Dependence of the Na/K Pump

    E-Print Network [OSTI]

    Gadsby, David

    Topical Review Voltage Dependence of the Na/K Pump R.F. Rakowski1 , D.C. Gadsby2 , P. De Weer3 1, Philadelphia, PA 19104, USA Received: 2 August 1996/Revised: 13 September 1996 Introduction Whether Na/K pump & Rakowski, 1988). While it follows from first principles that the rate of net forward Na/K pumping must

  13. Electrodic voltages accompanying stimulated bioremediation of a uraniumcontaminated aquifer

    E-Print Network [OSTI]

    Hubbard, Susan

    the accumulation of dissolved sulfide and the removal of uranium from groundwater. The anomalies persisted for 45. Within 10 days of the voltage decrease, uranium concentrations rebounded from 0.2 to 0.8 mM, a level of bioreduced contaminants, such as uranium. Citation: Williams, K. H., A. L. N'Guessan, J. Druhan, P. E. Long

  14. Voltage Sequence Control Based High-Current Rectifier System

    E-Print Network [OSTI]

    Paderborn, Universitt

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

  15. Ultra-compact Marx-type high-voltage generator

    DOE Patents [OSTI]

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

    2000-01-01T23:59:59.000Z

    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.

  16. Hierarchical Control Scheme for Voltage Unbalance Compensation in Islanded Microgrids

    E-Print Network [OSTI]

    Vasquez, Juan Carlos

    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

  17. Energy Efficient Datapath Scheduling using Multiple Voltages and Dynamic Clocking

    E-Print Network [OSTI]

    Mohanty, Saraju P.

    consumption of a device has to be minimum to increase battery life, the energy-delay- product hasEnergy Efficient Datapath Scheduling using Multiple Voltages and Dynamic Clocking Saraju P. Mohanty clocking in a co-ordinated manner in order to reduce energy consumption of datapath circuits. In dynamic

  18. Smart Grid Voltage Sag Detection using Instantaneous Features Extraction

    E-Print Network [OSTI]

    Boyer, Edmond

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

  19. Energy Efficiency in Low Voltage Hall Thrusters Jerry L. Ross

    E-Print Network [OSTI]

    King, Lyon B.

    Energy Efficiency in Low Voltage Hall Thrusters Jerry L. Ross Lyon B. King Energy efficiency/s of xenon. Acceleration and current efficiencies were compared to thrust efficiency over a range of magnet coil current values of 0 A - 2.5 A. Acceleration efficiencies were obtained with a 4-grid Retarding

  20. Contribution Allocation for Voltage Stability In Deregulated Power Systems

    E-Print Network [OSTI]

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

  1. Field Optimization of Three Dimensional High Voltage C. Trinitis

    E-Print Network [OSTI]

    Stamatakis, Alexandros

    Field Optimization of Three Dimensional High Voltage Equipment C. Trinitis Lehrstuhl f The goal of finding an optimal electric field strength distribution for arbitrary three di­ mensional­ cal optimization algorithm. The package ob­ tained from these three components is then able

  2. High Voltage DC Transmission 1.0 Introduction

    E-Print Network [OSTI]

    McCalley, James D.

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

  3. High Voltage DC Transmission 2 1.0 Introduction

    E-Print Network [OSTI]

    McCalley, James D.

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

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

    E-Print Network [OSTI]

    Chaudhary, Sanjay

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

  5. Addition and subtraction of spin pumping voltages in magnetic hybrid structures

    SciTech Connect (OSTI)

    Azevedo, A., E-mail: aac@df.ufpe.br; Alves Santos, O.; Cunha, R. O.; Rezende, S. M. [Departamento de Fsica, Universidade Federal de Pernambuco, 50670-901 Recife, PE (Brazil); Rodrguez-Surez, R. [Facultad de Fsica, Pontificia Universidad Catlica de Chile, Casilla 306, Santiago (Chile)

    2014-04-14T23:59:59.000Z

    We report an investigation of the spin pumping voltage generated in bilayers of ferromagnetic/normal metal in which the ferromagnetic layer is yttrium iron garnet or Permalloy and the normal-metal layer is Pt or Ta. We also investigated a special case in which the voltage is detected in single layer of Permalloy under ferromagnetic resonance condition. It is shown that the spin pumping voltage generated in metallic bilayers have contributions from both layers and the resulting voltage depends on the relative signs of charge currents generated by the inverse spin Hall effect. For instance, the spin pumping voltage generated in Ta has the same sign as the one generate in single layer of Permalloy, but contrary to the voltage generated in Pt. When the voltage is measured in shunted metallic bilayers, the resulting voltage can be a sum or a subtraction of the voltages generated in both layers.

  6. Firewater system inadvertent actuation frequencies

    SciTech Connect (OSTI)

    Schroeder, J.A. [EG and G Idaho, Inc., Idaho Falls, ID (United States); Eide, S.A. [Los Alamos Technical Associates, Inc., Albuquerque, NM (United States)

    1993-04-01T23:59:59.000Z

    This paper presents some recommended generic values for fire protection system inadvertent actuation frequencies. The frequencies are based on actual data from Department of Energy and commercial reactor plant facilities.

  7. Firewater system inadvertent actuation frequencies

    SciTech Connect (OSTI)

    Schroeder, J.A. (EG and G Idaho, Inc., Idaho Falls, ID (United States)); Eide, S.A. (Los Alamos Technical Associates, Inc., Albuquerque, NM (United States))

    1993-01-01T23:59:59.000Z

    This paper presents some recommended generic values for fire protection system inadvertent actuation frequencies. The frequencies are based on actual data from Department of Energy and commercial reactor plant facilities.

  8. A frequency-domain transient stability criterion for normal contingencies

    SciTech Connect (OSTI)

    Marceau, R.J.; Rizzi, J.C. [Ecole Polytechnique de Montreal, Quebec (Canada). Dept. of Electrical Engineering] [Ecole Polytechnique de Montreal, Quebec (Canada). Dept. of Electrical Engineering; Mailhot, R. [Hydro-Quebec, Montreal, Quebec (Canada)] [Hydro-Quebec, Montreal, Quebec (Canada)

    1995-08-01T23:59:59.000Z

    In a previous paper, a simple frequency-domain stability criterion was proposed for networks near the stability limit subjected to a 3-phase fault with no loss of line. The criterion can be summarized as follows: if a system is stable, the phase angle of the Fourier transform of a network`s transient voltage response exhibits a clockwise polar plot behavior at all buses (i.e. for increasing frequency); if the system is unstable, it exhibits a counterclockwise behavior in at least one location. Though these results are of interest, the criterion would be of greater practical use in mechanizing dynamic security analysis if it could be extended to the types of contingencies actually used in security analysis, namely normal contingencies. Normal contingencies are commonly defined as the loss of any element in a power system, either spontaneously or preceded by a fault, and such changes in topology impact post-contingency steady-state voltages in addition to their transient behavior. The present paper shows how such cases can be treated, thereby extending the applicable range of the criterion to normal contingencies.

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

    E-Print Network [OSTI]

    Moawwad, Ahmed

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

  10. Novel techniques for fault location, voltage profile calculation and visualization of transients

    E-Print Network [OSTI]

    Evrenosoglu, Cansin Yaman

    2009-05-15T23:59:59.000Z

    techniques of voltage profiles along transmission lines. A simple yet effective approach to accurately and rapidly obtain the voltage profile along a transmission line during fault transients is presented. The objective of the presented method is to eliminate...

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

    E-Print Network [OSTI]

    Guyton, Matthew C. (Matthew Christopher)

    2010-01-01T23:59:59.000Z

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

  12. Dynamic photorefractivity guided by single-pulse voltage

    SciTech Connect (OSTI)

    Agashkov, A. V., E-mail: agashkov@inel.bas.net.by; Kovalev, A. A. [National Academy of Sciences of Belarus, Institute of Electronics (Belarus); Parka, J. [Military University of Technology, Institute of Applied Physics (Poland)

    2008-03-15T23:59:59.000Z

    The dynamic photorefractivity in a cell with photoconducting orienting layers, filled with a nematic liquid crystal (LC) 6CHBT and a mixture of anthraquinone dyes AD1 and AD2, has been investigated. The single-pulse mode, in which the polarity and amplitude of a dc electric field applied to an LC cell are switched for a fixed time interval, has been used. The scheme of dynamic self-diffraction of low-power laser beams was used in the experiment. The dependences of the width and intensity of diffraction pulses on the bias and switching voltages have been investigated. It is established that the width and intensity of the diffraction pulse arising after initial voltage recovery depends also on the switching pulse width. At the optimal width of the control pulse, the diffraction efficiency increases by two orders of magnitude.

  13. Analysis of Solar Cell Quality Using Voltage Metrics: Preprint

    SciTech Connect (OSTI)

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

    2012-06-01T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

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

    2010-09-29T23:59:59.000Z

    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.

  15. Low Voltage Reversible Electrowetting Exploiting Lubricated Polymer Honeycomb Substrates

    E-Print Network [OSTI]

    Edward Bormashenko; Roman Pogreb; Yelena Bormashenko; Roman Grynyov; Oleg Gendelman

    2014-06-16T23:59:59.000Z

    Low-voltage electrowetting-on-dielectric scheme realized with lubricated honeycomb polymer surfaces is reported. Polycarbonate honeycomb reliefs manufactured with the breath-figures self-assembly were impregnated with silicone and castor oils. The onset of the reversible electrowetting for silicone oil impregnated substrates occurred at 35 V, whereas for castor oil impregnated ones it took place at 80 V. The semi-quantitative analysis of electrowetting of impregnated surfaces is proposed.

  16. Magnetic shielding of Hall thrusters at high discharge voltages

    SciTech Connect (OSTI)

    Mikellides, Ioannis G., E-mail: Ioannis.G.Mikellides@jpl.nasa.gov; Hofer, Richard R.; Katz, Ira; Goebel, Dan M. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109 (United States)

    2014-08-07T23:59:59.000Z

    A series of numerical simulations and experiments have been performed to assess the effectiveness of magnetic shielding in a Hall thruster operating in the discharge voltage range of 300700?V (I{sub sp}???20002700?s) at 6?kW, and 800?V (I{sub sp} ? 3000) at 9?kW. At 6?kW, the magnetic field topology with which highly effective magnetic shielding was previously demonstrated at 300?V has been retained for all other discharge voltages; only the magnitude of the field has been changed to achieve optimum thruster performance. It is found that magnetic shielding remains highly effective for all discharge voltages studied. This is because the channel is long enough to allow hot electrons near the channel exit to cool significantly upon reaching the anode. Thus, despite the rise of the maximum electron temperature in the channel with discharge voltage, the electrons along the grazing lines of force remain cold enough to eliminate or reduce significantly parallel gradients of the plasma potential near the walls. Computed maximum erosion rates in the range of 300700?V are found not to exceed 10{sup ?2}?mm/kh. Such rates are ?3 orders of magnitude less than those observed in the unshielded version of the same thruster at 300?V. At 9?kW and 800?V, saturation of the magnetic circuit did not allow for precisely the same magnetic shielding topology as that employed during the 6-kW operation since this thruster was not designed to operate at this condition. Consequently, the maximum erosion rate at the inner wall is found to be ?1 order of magnitude higher (?10{sup ?1}?mm/kh) than that at 6?kW. At the outer wall, the ion energy is found to be below the sputtering yield threshold so no measurable erosion is expected.

  17. Linear inductive voltage adders (IVA) for advanced hydrodynamic radiography

    SciTech Connect (OSTI)

    Mazarakis, M.G.; Boyes, J.D.; Johnson, D.L. [and others

    1998-09-01T23:59:59.000Z

    The electron beam which drifts through the multiple cavities of conventional induction linacs (LIA) is replaced in an IVA by a cylindrical metal conductor which extends along the entire length of the device and effectuates the addition of the accelerator cavity voltages. In the approach to radiography, the linear inductive voltage adder drives a magnetically immersed electron diode with a millimeter diameter cathode electrode and a planar anode/bremsstrahlung converter. Both anode and cathode electrodes are immersed in a strong (15--50 T) solenoidal magnetic field. The electron beam cross section is approximately of the same size as the cathode needle and generates a similar size, very intense x-ray beam when it strikes the anode converter. An IVA driven diode can produce electron beams of equal size and energy as a LIA but with much higher currents (40--50 kA versus 4--5 kA), simpler hardware and thus lower cost. The authors present here first experimental validations of the technology utilizing HERMES 3 and SABRE IVA accelerators. The electron beam voltage and current were respectively of the order of 10 MV and 40 kA. X-ray doses of up to 1 kR {at} 1 m and spot sizes as small as 1.7 mm (at 200 R doses) were measured.

  18. Fiber optic current monitor for high-voltage applications

    DOE Patents [OSTI]

    Renda, G.F.

    1992-04-21T23:59:59.000Z

    A current monitor which derives its power from the conductor being measured for bidirectionally measuring the magnitude of current (from DC to above 50 khz) flowing through a conductor across which a relatively high level DC voltage is applied, includes a pair of identical transmitter modules connected in opposite polarity to one another in series with the conductor being monitored, for producing from one module a first light signal having an intensity directly proportional to the magnitude of current flowing in one direction through the conductor during one period of time, and from the other module a second light signal having an intensity directly proportional to the magnitude of current flowing in the opposite direction through the conductor during another period of time, and a receiver located in a safe area remote from the high voltage area for receiving the first and second light signals, and converting the same to first and second voltage signals having levels indicative of the magnitude of current being measured at a given time. 6 figs.

  19. Advanced Gate Drive for the SNS High Voltage Converter Modulator

    SciTech Connect (OSTI)

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

    2009-05-07T23:59:59.000Z

    SLAC National Accelerator Laboratory is developing a next generation H-bridge switch plate [1], a critical component of the SNS High Voltage Converter Modulator [2]. As part of that effort, a new IGBT gate driver has been developed. The drivers are an integral part of the switch plate, which are essential to ensuring fault-tolerant, high-performance operation of the modulator. The redesigned driver improves upon the existing gate drive in several ways. The new gate driver has improved fault detection and suppression capabilities; suppression of shoot-through and over-voltage conditions, monitoring of dI/dt and Vce(sat) for fast over-current detection and suppression, and redundant power isolation are some of the added features. In addition, triggering insertion delay is reduced by a factor of four compared to the existing driver. This paper details the design and performance of the new IGBT gate driver. A simplified schematic and description of the construction are included. The operation of the fast over-current detection circuits, active IGBT over-voltage protection circuit, shoot-through prevention circuitry, and control power isolation breakdown detection circuit are discussed.

  20. Thermally-induced voltage alteration for integrated circuit analysis

    DOE Patents [OSTI]

    Cole, Jr., Edward I. (Albuquerque, NM)

    2000-01-01T23:59:59.000Z

    A thermally-induced voltage alteration (TIVA) apparatus and method are disclosed for analyzing an integrated circuit (IC) either from a device side of the IC or through the IC substrate to locate any open-circuit or short-circuit defects therein. The TIVA apparatus uses constant-current biasing of the IC while scanning a focused laser beam over electrical conductors (i.e. a patterned metallization) in the IC to produce localized heating of the conductors. This localized heating produces a thermoelectric potential due to the Seebeck effect in any conductors with open-circuit defects and a resistance change in any conductors with short-circuit defects, both of which alter the power demand by the IC and thereby change the voltage of a source or power supply providing the constant-current biasing. By measuring the change in the supply voltage and the position of the focused and scanned laser beam over time, any open-circuit or short-circuit defects in the IC can be located and imaged. The TIVA apparatus can be formed in part from a scanning optical microscope, and has applications for qualification testing or failure analysis of ICs.

  1. Thermally-induced voltage alteration for analysis of microelectromechanical devices

    DOE Patents [OSTI]

    Walraven, Jeremy A. (Albuquerque, NM); Cole, Jr., Edward I. (Albuquerque, NM)

    2002-01-01T23:59:59.000Z

    A thermally-induced voltage alteration (TIVA) apparatus and method are disclosed for analyzing a microelectromechanical (MEM) device with or without on-board integrated circuitry. One embodiment of the TIVA apparatus uses constant-current biasing of the MEM device while scanning a focused laser beam over electrically-active members therein to produce localized heating which alters the power demand of the MEM device and thereby changes the voltage of the constant-current source. This changing voltage of the constant-current source can be measured and used in combination with the position of the focused and scanned laser beam to generate an image of any short-circuit defects in the MEM device (e.g. due to stiction or fabrication defects). In another embodiment of the TIVA apparatus, an image can be generated directly from a thermoelectric potential produced by localized laser heating at the location of any short-circuit defects in the MEM device, without any need for supplying power to the MEM device. The TIVA apparatus can be formed, in part, from a scanning optical microscope, and has applications for qualification testing or failure analysis of MEM devices.

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

    E-Print Network [OSTI]

    Pota, Himanshu Roy

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

  3. Impact of Compiler Optimizations on Voltage Droops and Reliability of an SMT, Multi-Core Processor

    E-Print Network [OSTI]

    John, Lizy Kurian

    Impact of Compiler Optimizations on Voltage Droops and Reliability of an SMT, Multi-Core Processor unreliable operation in microprocessors. Voltage droops due to di/dt effects have been studied in the past, however no prior work studies the effect of compiler optimizations on voltage droops. Past work has

  4. Analysis of Instruction-level Vulnerability to Dynamic Voltage and Temperature Variations

    E-Print Network [OSTI]

    Gupta, Rajesh

    and supply voltage droops [2]. Static process variations can sometimes be mitigated through binning of dynamic variation from environmental and workload changes include supply voltage droops and temperature changes. Voltage droops result from abrupt changes in the switching activity, inducing large current

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

    E-Print Network [OSTI]

    Llope, William J.

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

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

    E-Print Network [OSTI]

    Bellan, Paul M.

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

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

    E-Print Network [OSTI]

    Lee, Thomas H.

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

  8. EFFECTS OF SUBSTRATE ON PHASE-NOISE OF BIPOLAR VOLTAGE-CONTROLLED OSCILLATORS

    E-Print Network [OSTI]

    Serdijn, Wouter A.

    EFFECTS OF SUBSTRATE ON PHASE-NOISE OF BIPOLAR VOLTAGE-CONTROLLED OSCILLATORS Aleksandar Tasic predict a dramatically different performance of the oscillators, being different phase-noise, voltage of quasi-tapped bipolar voltage-controlled oscillators [2], phase- noise being of most interest. Contrary

  9. Fast Optimization of Nano-CMOS Voltage-Controlled Oscillator using Polynomial Regression and Genetic Algorithm

    E-Print Network [OSTI]

    Mohanty, Saraju P.

    Fast Optimization of Nano-CMOS Voltage-Controlled Oscillator using Polynomial Regression in a current-starved 50nm voltage-controlled oscillator (VCO). Accurate polynomial-regression based models have-CMOS), Voltage-Controlled Oscillator (VCO). 1. Introduction Digital design exploration and optimization is highly

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

    E-Print Network [OSTI]

    Paris-Sud XI, Universit de

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

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

    E-Print Network [OSTI]

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

  12. Low-Voltage Ride-Through Techniques for DFIG-Based Wind Turbines

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Low-Voltage Ride-Through Techniques for DFIG-Based Wind Turbines: State-of-the-Art Review deals with low-voltage ride-through (LVRT) capability of wind turbines (WTs) and in particular those as to index some emerging solutions. Index Terms--Wind turbine, doubly-fed induction generator, low voltage

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

    SciTech Connect (OSTI)

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

    2013-06-25T23:59:59.000Z

    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.

  14. Voltage-Sensitivity of Motoneuron NMDA Receptor Channels Is Modulated by Serotonin in the Neonatal Rat Spinal Cord

    E-Print Network [OSTI]

    Manitoba, University of

    isolated in tetrodotoxin, induces nonlinear membrane behavior that results in voltage oscillations which generate rhythmic voltage oscillations in the presence of NMDA and synaptic blockade (with tetrodotoxin application induces neither voltage oscillations (in synaptically isolated motoneurons) nor locomotor network

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

    SciTech Connect (OSTI)

    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

    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.

  16. Frequency mixing crystal

    DOE Patents [OSTI]

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

    1992-01-01T23:59:59.000Z

    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.

  17. High frequency nanotube oscillator

    DOE Patents [OSTI]

    Peng, Haibing (Houston, TX); Zettl, Alexander K. (Kensington, TX)

    2012-02-21T23:59:59.000Z

    A tunable nanostructure such as a nanotube is used to make an electromechanical oscillator. The mechanically oscillating nanotube can be provided with inertial clamps in the form of metal beads. The metal beads serve to clamp the nanotube so that the fundamental resonance frequency is in the microwave range, i.e., greater than at least 1 GHz, and up to 4 GHz and beyond. An electric current can be run through the nanotube to cause the metal beads to move along the nanotube and changing the length of the intervening nanotube segments. The oscillator can operate at ambient temperature and in air without significant loss of resonance quality. The nanotube is can be fabricated in a semiconductor style process and the device can be provided with source, drain, and gate electrodes, which may be connected to appropriate circuitry for driving and measuring the oscillation. Novel driving and measuring circuits are also disclosed.

  18. Frequency doubling crystals

    DOE Patents [OSTI]

    Wang, Francis (Danville, CA); Velsko, Stephan P. (Livermore, CA)

    1989-01-01T23:59:59.000Z

    A systematic approach to the production of frequency conversion crystals is described in which a chiral molecule has attached to it a "harmonic generating unit" which contributes to the noncentrosymmetry of the molecule. Certain preferred embodiments of such harmonic generating units include carboxylate, guanadyly and imidazolyl units. Certain preferred crystals include L-arginine fluoride, deuterated L-arginine fluoride, L-arginine chloride monohydrate, L-arginine acetate, dithallium tartrate, ammonium N-acetyl valine, N-acetyl tyrosine and N-acetyl hydroxyproline. Chemical modifications of the chiral molecule, such as deuteration, halogenation and controlled counterion substitution are available to adapt the dispersive properties of a crystal in a particular wavelength region.

  19. Characteristics of radio-frequency atmospheric pressure dielectric-barrier discharge with dielectric electrodes

    SciTech Connect (OSTI)

    Hussain, S., E-mail: shussain@uos.edu.pk, E-mail: shussainuos@yahoo.com; Qazi, H. I. A.; Badar, M. A. [Department of Physics, University of Sargodha, 40100 Sargodha (Pakistan)] [Department of Physics, University of Sargodha, 40100 Sargodha (Pakistan)

    2014-03-15T23:59:59.000Z

    An experimental investigation to characterize the properties and highlight the benefits of atmospheric pressure radio-frequency dielectric-barrier discharge (rf DBD) with dielectric electrodes fabricated by anodizing aluminium substrate is presented. The current-voltage characteristics and millisecond images are used to distinguish the ? and ? modes. This atmospheric rf DBD is observed to retain the discharge volume without constriction in ? mode. Optical emission spectroscopy demonstrates that the large discharge current leads to more abundant reactive species in this plasma source.

  20. Strategies for Voltage Control and Transient Stability Assessment

    SciTech Connect (OSTI)

    Hiskens, Ian A.

    2013-09-25T23:59:59.000Z

    As wind generation grows, its influence on power system performance will becoming increasingly noticeable. Wind generation di#11;ffers from traditional forms of generation in numerous ways though, motivating the need to reconsider the usual approaches to power system assessment and performance enhancement. The project has investigated the impact of wind generation on transient stability and voltage control, identifying and addressing issues at three distinct levels of the power system: 1) at the device level, the physical characteristics of wind turbine generators (WTGs) are quite unlike those of synchronous machines, 2) at the wind-farm level, the provision of reactive support is achieved through coordination of numerous dissimilar devices, rather than straightforward generator control, and 3) from a systems perspective, the location of wind-farms on the sub-transmission network, coupled with the variability inherent in their power output, can cause complex voltage control issues. The project has sought to develop a thorough understanding of the dynamic behaviour of type-3 WTGs, and in particular the WECC generic model. The behaviour of such models is governed by interactions between the continuous dynamics of state variables and discrete events associated with limits. It was shown that these interactions can be quite complex, and may lead to switching deadlock that prevents continuation of the trajectory. Switching hysteresis was proposed for eliminating deadlock situations. Various type-3 WTG models include control blocks that duplicate integrators. It was shown that this leads to non-uniqueness in the conditions governing steady-state, and may result in pre- and post-disturbance equilibria not coinciding. It also gives rise to a zero eigenvalue in the linearized WTG model. In order to eliminate the anomalous behaviour revealed through this investigation, WECC has now released a new generic model for type-3 WTGs. Wind-farms typically incorporate a variety of voltage control equipment including tapchanging transformers, switched capacitors, SVCs, STATCOMs and the WTGs themselves. The project has considered the coordinated control of this equipment, and has addressed a range of issues that arise in wind-farm operation. The #12;first concerns the ability of WTGs to meet reactive power requirements when voltage saturation in the collector network restricts the reactive power availability of individual generators. Secondly, dynamic interactions between voltage regulating devices have been investigated. It was found that under certain realistic conditions, tap-changing transformers may exhibit instability. In order to meet cost, maintenance, fault tolerance and other requirements, it is desirable for voltage control equipment to be treated as an integrated system rather than as independent devices. The resulting high-level scheduling of wind-farm reactive support has been investigated. In addressing this control problem, several forms of future information were considered, including exact future knowledge and stochastic predictions. Deterministic and Stochastic Dynamic Programming techniques were used in the development of control algorithms. The results demonstrated that while exact future knowledge is very useful, simple prediction methods yield little bene#12;fit. The integration of inherently variable wind generation into weak grids, particularly subtransmission networks that are characterized by low X=R ratios, aff#11;ects bus voltages, regulating devices and line flows. The meshed structure of these networks adds to the complexity, especially when wind generation is distributed across multiple nodes. A range of techniques have been considered for analyzing the impact of wind variability on weak grids. Sensitivity analysis, based on the power-flow Jacobian, was used to highlight sections of a system that are most severely a#11;ffected by wind-power variations. A continuation power flow was used to determine parameter changes that reduce the impact of wind-power variability. It was also used to explore interactions betw

  1. Performance of the OVP/UVP and OFP/UFP method with voltage and frequency dependent loads

    E-Print Network [OSTI]

    Kirtley, James L., Jr.

    In previous literature, constant RLC loads were assumed to impose, on the islanding detection method, the hardest detectable case. For this reason, distributed-generation (DG) islanding studies are usually analyzed and ...

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

    E-Print Network [OSTI]

    Wang, Weihuang

    2009-05-15T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

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

    2010-12-07T23:59:59.000Z

    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

  4. Genomic analyses of induced hypercholesterolemia and atherosclerosis in a mixed breed colony of dogs and developmental abnormalities in the Havanese

    E-Print Network [OSTI]

    Starr, Alison Nicole

    2009-05-15T23:59:59.000Z

    ............................................................................ 2 Linkage analyses ............................................................................ 3 Population structures for research .................................................. 4 Atherosclerosis... ............................................................................................ 38 Discussion ...................................................................................... 46 IV CHROMOSOME-SPECIFIC LINKAGE ANALYSES OF DEVELOPMENTAL ABNORMALITIES IN THE HAVANESE DOG BREED...

  5. A quadratic cumulative production model for the material balance of an abnormally pressured gas reservoir

    E-Print Network [OSTI]

    Gonzalez, Felix Eduardo

    2005-02-17T23:59:59.000Z

    for the case of an abnormally-pressured gas reservoir. The primary assumption in this derivation is that WGp <1 or Ce(p)(pi-p)<1. Further, we can proceed by assuming that W is either constant or some arbitrary function. If we assume W...

  6. NTL Detection of Electricity Theft and Abnormalities for Large Power Consumers In TNB Malaysia

    E-Print Network [OSTI]

    Ducatelle, Frederick

    in power utilities originating from electricity theft and other customer malfeasances are termed as Non]. Investigations are undertaken by electric utility companies to assess the impact of technical lossesNTL Detection of Electricity Theft and Abnormalities for Large Power Consumers In TNB Malaysia J

  7. Relationship of sleep abnormalities to patient genotypes in Prader-Willi syndrome

    SciTech Connect (OSTI)

    Vgontzas, A.N.; Kales, A.; Bixler, E.O. [Pennsylvania State Univ., Hershey, PA (United States)] [and others] [Pennsylvania State Univ., Hershey, PA (United States); and others

    1996-09-20T23:59:59.000Z

    To assess whether sleep abnormalities are related to the genetic abnormalities in Prader-Willi Syndrome (PWS), we performed polysomnographic studies (nighttime and daytime) and determined the chromosome 15 genotypes in eight patients with PWS. Four patients demonstrated sleep onset REM periods (SOREM), and five met the objective polysomnographic criteria for severe or moderate excessive daytime sleepiness (EDS). Three of the four patients with SOREM displayed a paternally derived deletion of chromosome 15q11-q13, whereas the fourth exhibited maternal uniparental heterodisomy in this chromosomal region (UPD). Two of the four patients that did not display SOREM carried paternally derived deletions; the remaining two demonstrated UPD. Four of the five patients with EDS displayed paternal deletions, and the fifth exhibited UPD. One of three patients without evidence of EDS demonstrated paternal deletion; the remaining two showed UPD. Although neither EDS nor SOREM was not consistently associated with a specific genetic abnormality, these phenotypes may be more common in patients with paternal deletions than in those with UPD. Sleep abnormalities in PWS cannot be explained by a single genetic model. 32 refs., 1 tab.

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

    E-Print Network [OSTI]

    Rosales, Rmer E.

    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

  9. Methods, systems and apparatus for controlling third harmonic voltage when operating a multi-space machine in an overmodulation region

    SciTech Connect (OSTI)

    Perisic, Milun; Kinoshita, Michael H; Ranson, Ray M; Gallegos-Lopez, Gabriel

    2014-06-03T23:59:59.000Z

    Methods, system and apparatus are provided for controlling third harmonic voltages when operating a multi-phase machine in an overmodulation region. The multi-phase machine can be, for example, a five-phase machine in a vector controlled motor drive system that includes a five-phase PWM controlled inverter module that drives the five-phase machine. Techniques for overmodulating a reference voltage vector are provided. For example, when the reference voltage vector is determined to be within the overmodulation region, an angle of the reference voltage vector can be modified to generate a reference voltage overmodulation control angle, and a magnitude of the reference voltage vector can be modified, based on the reference voltage overmodulation control angle, to generate a modified magnitude of the reference voltage vector. By modifying the reference voltage vector, voltage command signals that control a five-phase inverter module can be optimized to increase output voltages generated by the five-phase inverter module.

  10. Hydraulic impulse generator and frequency sweep mechanism for borehole applications

    DOE Patents [OSTI]

    Kolle, Jack J.; Marvin, Mark H.; Theimer, Kenneth J.

    2006-11-21T23:59:59.000Z

    This invention discloses a valve that generates a hydraulic negative pressure pulse and a frequency modulator for the creation of a powerful, broadband swept impulse seismic signal at the drill bit during drilling operations. The signal can be received at monitoring points on the surface or underground locations using geophones. The time required for the seismic signal to travel from the source to the receiver directly and via reflections is used to calculate seismic velocity and other formation properties near the source and between the source and receiver. This information can be used for vertical seismic profiling of formations drilled, to check the location of the bit, or to detect the presence of abnormal pore pressure ahead of the bit. The hydraulic negative pressure pulse can also be used to enhance drilling and production of wells.

  11. Abstract--In this paper, we present the voltage build up process and the terminal voltage control of an isolated wind

    E-Print Network [OSTI]

    Paris-Sud XI, Universit de

    Abstract-- In this paper, we present the voltage build up process and the terminal voltage control that when capacitors are connected across the stator terminals of an induction machine, driven in the stator will continue to grow until steady-state condition is reached [2, 3]. However, self excitation has

  12. Induction of nuclear fission by high-voltage application

    E-Print Network [OSTI]

    Hirokazu Maruyama

    2007-11-20T23:59:59.000Z

    In nuclear power generation, fissile materials are mainly used. For example, $U^{235}$ is fissile and therefore quite essential for use of nuclear energy. However, the material $U^{235}$ has very small natural abundance less than 1 %. We should seek possibility of utilizing fissionable materials such as $U^{238}$ because natural abundance of such fissionable materials is generally much larger than fissile ones. In this paper, we show that thermal neutrons with vanishing kinetic energy can induce nuclear fission when high voltage is applied to fissionable materials. To obtain this result, we use the liquid-drop model for nuclei. Finally, we propose how fissionable materials can be utilized.

  13. Worldwide reliability surveys of high voltage circuit breakers

    SciTech Connect (OSTI)

    Heising, C.R.

    1995-05-01T23:59:59.000Z

    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.

  14. Light-weight DC to very high voltage DC converter

    DOE Patents [OSTI]

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

    1998-01-01T23:59:59.000Z

    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.

  15. Light-weight DC to very high voltage DC converter

    DOE Patents [OSTI]

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

    1998-06-30T23:59:59.000Z

    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.

  16. Outdoor PV Module Degradation of Current-Voltage Parameters: Preprint

    SciTech Connect (OSTI)

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

    2012-04-01T23:59:59.000Z

    Photovoltaic (PV) module degradation rate analysis quantifies the loss of PV power output over time and is useful for estimating the impact of degradation on the cost of energy. An understanding of the degradation of all current-voltage (I-V) parameters helps to determine the cause of the degradation and also gives useful information for the design of the system. This study reports on data collected from 12 distinct mono- and poly-crystalline modules deployed at the National Renewable Energy Laboratory (NREL) in Golden, Colorado. Most modules investigated showed < 0.5%/year decrease in maximum power due to short-circuit current decline.

  17. Self-monitoring high voltage transmission line suspension insulator

    DOE Patents [OSTI]

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

    1981-01-01T23:59:59.000Z

    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.

  18. Light-induced voltage alteration for integrated circuit analysis

    DOE Patents [OSTI]

    Cole, E.I. Jr.; Soden, J.M.

    1995-07-04T23:59:59.000Z

    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. 18 figs.

  19. Low Voltage Cables Market Analysis | OpenEI Community

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to: navigation, searchOf KilaueaInformation Other4Q07) WindLow Voltage Cables Market Analysis

  20. Low Voltage Cables Market Trends | OpenEI Community

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to: navigation, searchOf KilaueaInformation Other4Q07) WindLow Voltage Cables Market

  1. Low Voltage Cables Market size | OpenEI Community

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to: navigation, searchOf KilaueaInformation Other4Q07) WindLow Voltage Cables MarketLow

  2. Low Voltage Cables Market | OpenEI Community

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to: navigation, searchOf KilaueaInformation Other4Q07) WindLow Voltage Cables MarketLowLow

  3. HIGH-VOLTAGE SPINEL AND POLYANION CATHODES | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(Fact Sheet), GeothermalGrid Integration0-1HAWAI'I CLEANDepartmentDOEHIGH-VOLTAGE

  4. Acoustic resonance frequency locked photoacoustic spectrometer

    DOE Patents [OSTI]

    Pilgrim, Jeffrey S.; Bomse, David S.; Silver, Joel A.

    2003-09-09T23:59:59.000Z

    A photoacoustic spectroscopy method and apparatus for maintaining an acoustic source frequency on a sample cell resonance frequency comprising: providing an acoustic source to the sample cell, the acoustic source having a source frequency; repeatedly and continuously sweeping the source frequency across the resonance frequency at a sweep rate; and employing an odd-harmonic of the source frequency sweep rate to maintain the source frequency sweep centered on the resonance frequency.

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

    SciTech Connect (OSTI)

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

    2014-05-15T23:59:59.000Z

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

  6. Bi-directional power control system for voltage converter

    DOE Patents [OSTI]

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

    1999-05-11T23:59:59.000Z

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

  7. Bi-directional power control system for voltage converter

    DOE Patents [OSTI]

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

    1999-01-01T23:59:59.000Z

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

  8. Commercialization of Medium Voltage HTS Triax TM Cable Systems

    SciTech Connect (OSTI)

    Knoll, David

    2012-12-31T23:59:59.000Z

    The original project scope that was established in 2007 aimed to install a 1,700 meter (1.1 mile) medium voltage HTS Triax{TM} cable system into the utility grid in New Orleans, LA. In 2010, however, the utility partner withdrew from the project, so the 1,700 meter cable installation was cancelled and the scope of work was reduced. The work then concentrated on the specific barriers to commercialization of HTS cable technology. The modified scope included long-length HTS cable design and testing, high voltage factory test development, optimized cooling system development, and HTS cable life-cycle analysis. In 2012, Southwire again analyzed the market for HTS cables and deemed the near term market acceptance to be low. The scope of work was further reduced to the completion of tasks already started and to testing of the existing HTS cable system in Columbus, OH. The work completed under the project included: Long-length cable modeling and analysis HTS wire evaluation and testing Cable testing for AC losses Optimized cooling system design Life cycle testing of the HTS cable in Columbus, OH Project management. The 200 meter long HTS Triax{TM} cable in Columbus, OH was incorporated into the project under the initial scope changes as a test bed for life cycle testing as well as the site for an optimized HTS cable cooling system. The Columbus cable utilizes the HTS TriaxTM design, so it provided an economical tool for these of the project tasks.

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

    SciTech Connect (OSTI)

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

    2007-01-01T23:59:59.000Z

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

  10. Over Voltage in a Multi-sectioned Solenoid during a Quenching

    SciTech Connect (OSTI)

    Guo, Xinglong; Wang, Li; Pan, Heng; Wu, Hong; Liu, Xiaokun; Chen, Anbin; Green, M.A.; Xu, F.Y.

    2009-06-21T23:59:59.000Z

    Accurate analysis of over voltage in the superconducting solenoid during a quench is one of the bases for quench protection system design. Classical quench simulation methods can only give rough estimation of the over voltage within a magnet coil. In this paper, for multi-sectioned superconducting solenoid, based on the classical assumption of ellipsoidal normal zone, three-dimension al temperature results are mapped to the one-dimension of the wire, the temperature distribution along the wire and the resistances of each turn are obtained. The coil is treated as circuit comprised of turn resistances, turn self and mutual inductances. The turn resistive voltage, turn inductive voltage, and turn resultant voltage along the wire are calculated. As a result, maximum internal voltages, the layer-to-layer voltages and the turn-to-turn voltages are better estimated. Utilizing this method, the over voltage of a small solenoid and a large solenoid during quenching have been studied. The result shows that this method can well improve the over voltage estimate, especially when the coil is larger.

  11. SECURING RADIO FREQUENCY IDENTIFICATION (RFID)

    E-Print Network [OSTI]

    business process for an organization; as a result, the security risks for RFID systems and the controls for an organization; as a result, the security risks for RFID systems and the controls available to address themMay 2007 SECURING RADIO FREQUENCY IDENTIFICATION (RFID) SYSTEMS SECURING RADIO FREQUENCY

  12. Stabilized radio-frequency quadrupole

    DOE Patents [OSTI]

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

    1982-09-29T23:59:59.000Z

    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.

  13. Temperature dependent junction capacitance-voltage characteristics of Ni embedded TiN/SiO{sub 2}/p-Si metalinsulatorsemiconductor structure

    SciTech Connect (OSTI)

    Panda, J.; Nath, T. K., E-mail: tnath@phy.iitkgp.ernet.in [Department of Physics and Meteorology, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal 721302 (India); Chattopadhyay, S. [Department of Physics and Meteorology, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal 721302 (India); Amity Institute of Nano Technology, Amity University, Sector-125, Noida, Uttar Pradesh 201313 (India)

    2013-12-14T23:59:59.000Z

    This work presents the junction capacitancevoltage characteristics of highly textured/epitaxial Ni nanoparticle embedded in TiN matrix (TiN(Ni)) metal-insulator-semiconductor TiN(Ni)/SiO{sub 2}/p-Si (100) heterojunction in the temperature range of 10300?K. This heterojunction behaves as metal-semiconductor junction with unavoidable leakage through native oxide SiO{sub 2} layer. The clockwise hysteresis loop has been observed in the capacitance-voltage characteristics measured at various frequencies mainly due to presence of trap centers at the TiN(Ni)/SiO{sub 2} interface and these are temperature dependent. The spin-dependent trap charge effect at the interface influences the quadratic nature of the capacitance with magnetic field. The junction magnetocapacitance (JMC) is observed to be dependent on both temperature and frequency. The highest JMC of this heterojunction has been observed at 200?K at higher frequencies (100?kHz1?MHz). It is found that there is not much effect of band structure modification under magnetic field causing the JMC.

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

    E-Print Network [OSTI]

    Lemmon, Michael

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

  15. Design, development, and acceleration trials of radio-frequency quadrupole

    SciTech Connect (OSTI)

    Rao, S. V. L. S., E-mail: svlsrao@gmail.com; Jain, Piyush; Pande, Rajni; Roy, Shweta; Mathew, Jose V.; Kumar, Rajesh; Pande, Manjiri; Krishnagopal, S.; Gupta, S. K.; Singh, P. [Ion Accelerator Development Division, Bhabha Atomic Research Centre, Mumbai 400085 (India)] [Ion Accelerator Development Division, Bhabha Atomic Research Centre, Mumbai 400085 (India)

    2014-04-15T23:59:59.000Z

    A deuteron radio frequency quadrupole (RFQ) accelerator has been designed, fabricated, and tested at BARC, which will be used for neutron generation. The RFQ operates at a frequency of 350 MHz and needs an inter-vane voltage of 44 kV to accelerate the deuteron beam to 400 keV within a length of 1.03 m. The error analysis shows that the offset of two opposite vanes in the same direction by 100 ?m leads to a change in resonant frequency by 1.3 MHz and a significant change of fields in the quadrants (?40% with respect to average field). From the 3D analysis, we have observed that the unwanted dipole mode frequencies are very near to the quadrupole mode frequency which will make structure sensitive to the perturbations. In order to move the dipole modes away from the quadrupole modes, we have used the dipole stabilizer rods. The 5 wire transmission line theory was used to study the perturbative analysis of the RFQ and based on this a computer program has been written to tune the cavity to get required field distribution. Based on these studies, a 1.03 m long RFQ made of OFE copper has been fabricated and tested. Even though the RFQ was designed for deuteron (D{sup +}) beam, we tested it by accelerating both the proton (H{sup +}) and D{sup +} beams. The RFQ was operated in pulsed mode and accelerated both H{sup +} and D{sup +} beams to designed values of 200 and 400 keV, respectively. The measured parameters are in good agreement with the designed values validating our simulations and fabrication processes. In this paper, simulations, RF measurements, and beam commissioning results are presented.

  16. Bright and fast voltage reporters across the visible spectrum via electrochromic FRET (eFRET)

    E-Print Network [OSTI]

    Zou, Peng; Douglass, Adam D; Hochbaum, Daniel R; Brinks, Daan; Werley, Christopher A; Harrison, D Jed; Campbell, Robert E; Cohen, Adam E

    2014-01-01T23:59:59.000Z

    We present a palette of brightly fluorescent genetically encoded voltage indicators (GEVIs) with excitation and emission peaks spanning the visible spectrum, sensitivities from 6 - 10% Delta F/F per 100 mV, and half-maximal response times from 1 - 7 ms. A fluorescent protein is fused to an Archaerhodopsin-derived voltage sensor. Voltage-induced shifts in the absorption spectrum of the rhodopsin lead to voltage-dependent nonradiative quenching of the appended fluorescent protein. Through a library screen, we identified linkers and fluorescent protein combinations which reported neuronal action potentials in cultured rat hippocampal neurons with a single-trial signal-to-noise ratio from 6.6 to 11.6 in a 1 kHz imaging bandwidth at modest illumination intensity. The freedom to choose a voltage indicator from an array of colors facilitates multicolor voltage imaging, as well as combination with other optical reporters and optogenetic actuators.

  17. Design and Quasi-Equilibrium Analysis of a Distributed Frequency-Restoration Controller for Inverter-Based Microgrids

    SciTech Connect (OSTI)

    Ainsworth, Nathan G [ORNL] [ORNL; Grijalva, Prof. Santiago [Georgia Institute of Technology, Atlanta] [Georgia Institute of Technology, Atlanta

    2013-01-01T23:59:59.000Z

    This paper discusses a proposed frequency restoration controller which operates as an outer loop to frequency droop for voltage-source inverters. By quasi-equilibrium analysis, we show that the proposed controller is able to provide arbitrarily small steady-state frequency error while maintaing power sharing between inverters without need for communication or centralized control. We derive rate of convergence, discuss design considerations (including a fundamental trade-off that must be made in design), present a design procedure to meet a maximum frequency error requirement, and show simulation results verifying our analysis and design method. The proposed controller will allow flexible plug-and-play inverter-based networks to meet a specified maximum frequency error requirement.

  18. Understanding and Improving High Voltage Vacuum Insulators for Microsecond Pulses

    SciTech Connect (OSTI)

    Javedani, J B; Goerz, D A; Houck, T L; Lauer, E J; Speer, R D; Tully, L K; Vogtlin, G E; White, A D

    2007-03-05T23:59:59.000Z

    High voltage insulation is one of the main areas of pulsed power research and development, and dielectric breakdown is usually the limiting factor in attaining the highest possible performance in pulsed power devices. For many applications the delivery of pulsed power into a vacuum region is the most critical aspect of operation. The surface of an insulator exposed to vacuum can fail electrically at an applied field more than an order or magnitude below the bulk dielectric strength of the insulator. This mode of breakdown, called surface flashover, imposes serious limitations on the power flow into a vacuum region. This is especially troublesome for applications where high voltage conditioning of the insulator and electrodes is not practical and for applications where relatively long pulses, on the order of several microseconds, are required. The goal of this project is to establish a sound fundamental understanding of the mechanisms that lead to surface flashover, and then evaluate the most promising techniques to improve vacuum insulators and enable high voltage operation at stress levels near the intrinsic bulk breakdown limits of the material. The approach we proposed and followed was to develop this understanding through a combination of theoretical and computation methods coupled with experiments to validate and quantify expected behaviors. In this report we summarize our modeling and simulation efforts, theoretical studies, and experimental investigations. The computational work began by exploring the limits of commercially available codes and demonstrating methods to examine field enhancements and defect mechanisms at microscopic levels. Plasma simulations with particle codes used in conjunction with circuit models of the experimental apparatus enabled comparisons with experimental measurements. The large scale plasma (LSP) particle-in-cell (PIC) code was run on multiprocessor platforms and used to simulate expanding plasma conditions in vacuum gap regions. Algorithms were incorporated into LSP to handle secondary electron emission from dielectric materials to enable detailed simulations of flashover phenomenon. Theoretical studies were focused on explaining a possible mechanism for anode initiated surface flashover that involves an electron avalanche process starting near the anode, not a mechanism involving bulk dielectric breakdown. Experiments were performed in Engineering's Pulsed Power Lab using an available 100-kV, 10-{micro}s pulse generator and vacuum chamber. The initial experiments were done with polyethylene insulator material in the shape of a truncated cone cut at +45{sup o} angle between flat electrodes with a gap of 1.0 cm. The insulator was sized so there were no flashovers or breakdowns under nominal operating conditions. Insulator flashover or gap closure was induced by introducing a plasma source, a tuft of velvet, in proximity to the insulator or electrode.

  19. Atomic hydrogen densities in capacitively coupled very high-frequency plasmas in H{sub 2}: Effect of excitation frequency

    SciTech Connect (OSTI)

    Jolly, J.; Booth, J.-P. [Laboratoire de Physique et Technologie des Plasmas, Centre Nazionale de la Recherche Scientifique, Ecole Polytechnique, 91128 Palaiseau Cedex (France)

    2005-05-15T23:59:59.000Z

    Absolute hydrogen atom densities in pure hydrogen capacitive discharges were measured as a function of excitation frequency (13.56, 27.12, and 40.68 MHz), nominal electrical power, and gas pressure (between 0.1 and 1 Torr). Quantitative measurements were made using two-photon absorption laser-induced fluorescence (TALIF), put on an absolute scale by comparison with the TALIF signal from a known density of krypton gas, as proposed by Niemi, Schultz von Gathen, and Doebele [J. Phys. D 34, 2330 (2001)]. The H atom density increases with gas pressure and electrical power, and at a given power and pressure it increases significantly with excitation frequency. The latter can be attributed in part to increased electron density. However, time-resolved TALIF measurements in the afterglow showed that the H atom surface loss probabilities are not constant, becoming somewhat smaller when the sheath voltage is lowered, as is the case when the excitation frequency is increased, contributing to the increase in H density.

  20. Experimental study of frequency multipliers based on a GaAs/AlAs semiconductor superlattices in the terahertz frequency range

    SciTech Connect (OSTI)

    Paveliev, D. G., E-mail: pavelev@rf.unn.ru; Koshurinov, Y. I.; Ivanov, A. S. [Lobachevskii State University of Nizhny Novgorod (Russian Federation); Panin, A. N.; Vax, V. L.; Gavrilenko, V. I.; Antonov, A. V. [Russian Academy of Sciences, Institute for Physics of Microstructures (Russian Federation); Ustinov, V. M. [Russian Academy of Sciences, Ioffe Physical Technical Institute (Russian Federation); Zhukov, A. E. [Russian Academy of Sciences, St. Petersburg Academic University-Nanotechnology Research and Education Center (Russian Federation)

    2012-01-15T23:59:59.000Z

    Frequency multipliers based on a GaAs/AlAs semiconductor quantum superlattice have been experimentally studied. The power spectrum of the harmonics in the output signal from a multiplier with an input-signal frequency of 140-160 GHz has been measured. Planar diodes with a small active region (an area of 1-2 {mu}m{sup 2}) have been used in this study. For fabrication of the diodes, structures of heavily doped superlattices with the miniband width 24 meV have been used, these structures were grown by the molecular-beam epitaxy method. Measurements have been conducted using a BOMEM DA3.36 Fourier spectrometer equipped with a detector based on a bolometer cooled to the temperature of liquid helium. The results of the measurements have been used to plot the dependences of the power of the harmonics on the frequency in the range from 0.4 to 8.1 THz. It has been found that the character of the microwave-power distribution over the number of harmonics is close to the spectrum of a sequence of sign-alternating pulses which appear in the diode circuit when the applied voltage of the input signal exceeds the threshold of the diode. The minimal time of establishment of the pulse front and pulse duration are equal to 123 and 667 fs, respectively.

  1. Investigation of plasma diagnostics using a dual frequency harmonic technique

    SciTech Connect (OSTI)

    Kim, Dong-Hwan [Department of Nanoscale Semiconductor Engineering, Hanyang University, Seoul (Korea, Republic of); Kim, Young-Do; Cho, Sung-Won; Kim, Yu-Sin; Chung, Chin-Wook, E-mail: joykang@hanyang.ac.kr [Department of Electrical Engineering, Hanyang University, Seoul (Korea, Republic of)

    2014-09-07T23:59:59.000Z

    Plasma diagnostic methods using harmonic currents analysis of electrostatic probes were experimentally investigated to understand the differences in their measurement of the plasma parameters. When dual frequency voltage (?{sub 1},?{sub 2}) was applied to a probe, various harmonic currents (?{sub 1},?2?{sub 1},?{sub 2},?2?{sub 2},?{sub 2}?{sub 1},?{sub 2}2?{sub 1}) were generated due to the non-linearity of the probe sheath. The electron temperature can be obtained from the ratio of the two harmonics of the probe currents. According to the combinations of the two harmonics, the sensitivities in the measurement of the electron temperature differed, and this results in a difference of the electron temperature. From experiments and simulation, it is shown that this difference is caused by the systematic and random noise.

  2. A new method with high sensitivity and specificity for localization of abnormal parathyroid glands

    SciTech Connect (OSTI)

    Okerlund, M.D.; Sheldon, K.; Corpuz, S.; O'Connell, W.; Faulkner, D.; Clark, O.; Galante, M.

    1984-09-01T23:59:59.000Z

    A novel method for localization of abnormal parathyroid glands involving color-processing of nuclear scintigrams of the neck after injection of Thallium-201 and Technetium pertechnetate is presented with surgical correlation. Preoperative localization of single parathyroid adenomas was successful in 88% of previously unoperated patients and in 85.7% of those with adenomas not located at previous surgery. Eighty-three per cent of glands with secondary hyperplasia, 66% of glands with primary hyperplasia, and one carcinoma were localized. No abnormal studies were seen in non-hyperparathyroid hypercalcemia, and no false positive studies were seen. Localization appeared related to larger adenomas (300-5000 mg), although one of 60 mg was localized. Color-comparison dual-isotype scintigraphy was useful for localization of parathyroid adenomas and hyperplastic glands and exceeded the reported sensitivity of either ultrasonography or computerized tomography. It deserves wider evaluation in preoperative management of at least hyperparathyroidism of the primary or persistent types.

  3. Structure and distribution of abnormal pressures in the Vicksburg Formation (Oligocene), Hinde Field, Starr County, Texas

    E-Print Network [OSTI]

    Barrell, Kirk Arthur

    1988-01-01T23:59:59.000Z

    appear to be abnormally pressured on conductivity plots where the observed conductivity deviates from the normal trend. The first conductivity zone occurs in the Frio section at depths of 4, 000-5, 600 ft (1222-1711 m). Measured pressures... fault systems and the location of Hinde Field (Starr County) and McAllen Ranch Field (Hidalgo County)(Berg and Habeck, 1982). . . . . . . . . . ~ . ~ . . . Page Regional cross section of South Texas showing the location of the Vicksburg and Frio...

  4. Energy Recovery from High-frequency Clocks using DC-DC Converters M. Alimadadi, S. Sheikhaei, G. Lemieux, S. Mirabbasi, W. Dunford, P. Palmer.

    E-Print Network [OSTI]

    Lemieux, Guy

    . The redeployment reduces the total current draw from the primary supply. We call this concept energy recycling [4 with an increase in operating frequency. As a result, a large fraction of the total energy budget is used is the efficient generation of an on-chip voltage supply which differs from the level offered by the primary supply

  5. High-speed, sub-pull-in voltage MEMS switching.

    SciTech Connect (OSTI)

    Spahn, Olga Blum; Brewer, Steven; Olsson, Roy H.; Bogart, Gregory R.; Luck, David L.; Watts, Michael R.; Shaw, Michael J.; Nielson, Gregory N.; Resnick, Paul James; Tigges, Christopher P.; Grossetete, Grant David

    2008-01-01T23:59:59.000Z

    We have proposed and demonstrated MEMS switching devices that take advantage of the dynamic behavior of the MEMS devices to provide lower voltage actuation and higher switching speeds. We have explored the theory behind these switching techniques and have demonstrated these techniques in a range of devices including MEMS micromirror devices and in-plane parallel plate MEMS switches. In both devices we have demonstrated switching speeds under one microsecond which has essentially been a firm limit in MEMS switching. We also developed low-loss silicon waveguide technology and the ability to incorporate high-permittivity dielectric materials with MEMS. The successful development of these technologies have generated a number of new projects and have increased both the MEMS switching and optics capabilities of Sandia National Laboratories.

  6. (Insulating materials and large high voltage electric systems)

    SciTech Connect (OSTI)

    Dale, S.J.

    1990-09-18T23:59:59.000Z

    The traveler attended the 33rd Session of CIGRE (The International Conference on Large High Voltage Electric Systems in Paris, France) as a US technical expert advisor the Study Committee 15, Insulating Materials. Over 200 papers were discussed, contributed from over 45 countries at the conference on all aspects of electric power generation and transmission. Of special interest was a panel session on superconducting technology for electric power systems and the participation on a new task force on the electrical insulation at cryogenic temperatures. Significant insight was gained into the development of superconducting power technologies in Europe and Japan. CIGRE has set up a committee to follow the development in research on the biological effects of electric and magnetic fields. The traveler also visited the Centre for Electric Power Engineering at the University of Strathclyde, Glasgow, Scotland and discussed research on degradation of polymeric cable insulation and gas insulated equipment. 5 refs.

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

    SciTech Connect (OSTI)

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

    1997-11-01T23:59:59.000Z

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

  8. Effect of high-voltage nanosecond pulses on complex plasmas

    SciTech Connect (OSTI)

    Pustylnik, M. Y.; Ivlev, A. V.; Thomas, H. M.; Morfill, G. E. [Max-Planck-Institut fuer Extraterrestrische Physik, Giessenbachstrasse, 85741 Garching (Germany); Vasilyak, L. M.; Vetchinin, S. P.; Polyakov, D. N.; Fortov, V. E. [Joint Institute for High Temperatures, Russian Academy of Sciences, Izhorskaya 13/19, 125412 Moscow (Russian Federation)

    2009-11-15T23:59:59.000Z

    Influence of high-voltage (1-11 kV) pulses of nanosecond (20 ns) duration on microparticles levitating in a rf plasma is studied. It is shown that the pulses produce significant influence on the plasma, causing perturbations with the relaxation time of the order of 10{sup -4} s. This time is sufficient for the microparticle to acquire significant kinetic energy. Application of repetitive pulses leads to the vertical oscillations of the microparticles. Clusters, consisting of small number of microparticles, exhibit parametric instabilities of horizontal modes under the effect of repetitive pulses. It was shown that the parametric instability is caused by the vertical oscillations of the microparticles in the nonuniform environment of the sheath.

  9. High-voltage atmospheric breakdown across intervening rutile dielectrics.

    SciTech Connect (OSTI)

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

    2013-09-01T23:59:59.000Z

    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.

  10. Nanowire-based ternary transistor by threshold-voltage manipulation

    SciTech Connect (OSTI)

    Han, Junebeom; Lim, Taekyung; Bong, Jihye; Seo, Keumyoung; Ju, Sanghyun, E-mail: shju@kgu.ac.kr [Department of Physics, Kyonggi University, Suwon, Gyeonggi-Do 443-760 (Korea, Republic of); Kim, Sunkook [Department of Electronics and Radio Engineering, Kyung Hee University, Yongin, Gyeonggi-Do 446-701 (Korea, Republic of)

    2014-04-07T23:59:59.000Z

    We report on a ternary device consisting of two nanowire channels that have different threshold voltage (V{sub th}) values and show that three current stages can be produced. A microscale laser-beam shot was utilized to selectively anneal the nanowire channel area to be processed, and the amount of V{sub th} shift could be controlled by adjusting the laser wavelength. Microscale laser annealing process could control V{sub th} of the individual nanowire transistors while maintaining the other parameters the constant, such as the subthreshold slope, onoff current ratio, and mobility. This result could provide a potential for highly integrated and high-speed ternary circuits.

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

    SciTech Connect (OSTI)

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

    2010-04-30T23:59:59.000Z

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

  12. High voltage design structure for high temperature superconducting device

    DOE Patents [OSTI]

    Tekletsadik, Kasegn D. (Rexford, NY)

    2008-05-20T23:59:59.000Z

    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.

  13. System and method for floating-substrate passive voltage contrast

    DOE Patents [OSTI]

    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

    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.

  14. Summary of multiterminal high-voltage direct current transmission technology

    SciTech Connect (OSTI)

    Biggs, R.B.; Jewell, W.T.

    1984-05-01T23:59:59.000Z

    This report summarizes the present state of multiterminal (MT) high-voltage direct current (HVDC) power transmission. The purpose is to reassess the need for HVDC circuit breakers and to identify needed research for MT HVDC. The fundamentals of this technology are presented, and previous research and development is reviewed. Although no MT HVDC systems have yet been built, many concepts have been proposed. Some require a dc breaker, and others do not. Both options have advantages and disadvantages for various applications, so the selection will depend on the proposed application. Research is needed to define operating characteristics of various MT HVDC systems. In some applications, dc breakers will be useful, so research into HVDC interruption should continue. Also, dc fault detection and control algorithms for MT systems should be studied.

  15. PVREG - A photovoltaic voltage regulation investigation tool: Program reference manual

    SciTech Connect (OSTI)

    Garrett, D.L.; Sims, T.R.; Jones, R.A.; Jeter, S.M.

    1989-06-01T23:59:59.000Z

    This manual provides information for installing and maintaining the computer program PVREG, a program developed to study the impact of distributed photovoltaic systems on the voltage regulation of distribution systems. The manual describes installation on the Apollo workstation or the IBM PC-AT (or compatible), but the instructions and code description should be general enough to assist installation on other computers, also. The manual assumes that the user is well acquainted with the computer on which the program is to operate and with the operating system of that computer. The manual describes the program structure and models in detail and provides step-by-step installation instructions for both the Apollo and AT-compatible computers. 9 figs., 11 tabs.

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

    E-Print Network [OSTI]

    Vasquez, Juan Carlos

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

  17. Clustering-Based Simultaneous Task and Voltage Scheduling for NoC Systems

    E-Print Network [OSTI]

    Yang, Yu

    2011-08-08T23:59:59.000Z

    -means clustering. (a) cluster assignment. (b) center point moves to the mean of all elements in the cluster. : : : : : : : : : : : 16 4 One iteration in TILE clustering. There are four tiles T1,T2,T3 and T4. Two supply voltages are available. (a) TILE voltage... assignment at the beginning of iteration. (b) T4?s distances to the two voltages are re-evaluated. (c) T4 is assigned to a new voltage according to the re-evaluated distances. : : : : : : : : : : : : : : : : : : : : : : : : : : : 17 5 Comparison...

  18. activated si-gaas high-voltage: Topics by E-print Network

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

    Summary: ??This thesis is concerned with developing a new approach to high voltage transformers condition monitoring, which involve partial discharge (PD) measurement and...

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

    E-Print Network [OSTI]

    Shireen, Wajiha

    1990-01-01T23:59:59.000Z

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

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

    DOE Patents [OSTI]

    Murty, Balarama Vempaty (West Bloomfield, MI)

    2000-01-01T23:59:59.000Z

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

  1. Sacramento Area Voltage Support Final Environmental Impact Statement

    SciTech Connect (OSTI)

    N /A

    2003-09-19T23:59:59.000Z

    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.

  2. Sacramento Area Voltage Support Draft Environmental Impact Statement

    SciTech Connect (OSTI)

    N /A

    2002-11-15T23:59:59.000Z

    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.

  3. Raman Spectroscopy of DNA Packaging in Individual Human Sperm Cells distinguishes Normal from Abnormal Cells

    SciTech Connect (OSTI)

    Huser, T; Orme, C; Hollars, C; Corzett, M; Balhorn, R

    2009-03-09T23:59:59.000Z

    Healthy human males produce sperm cells of which about 25-40% have abnormal head shapes. Increases in the percentage of sperm exhibiting aberrant sperm head morphologies have been correlated with male infertility, and biochemical studies of pooled sperm have suggested that sperm with abnormal shape may contain DNA that has not been properly repackaged by protamine during spermatid development. We have used micro-Raman spectroscopy to obtain Raman spectra from individual human sperm cells and examined how differences in the Raman spectra of sperm chromatin correlate with cell shape. We show that Raman spectra of individual sperm cells contain vibrational marker modes that can be used to assess the efficiency of DNA-packaging for each cell. Raman spectra obtained from sperm cells with normal shape provide evidence that DNA in these sperm is very efficiently packaged. We find, however, that the relative protein content per cell and DNA packaging efficiencies are distributed over a relatively wide range for sperm cells with both normal and abnormal shape. These findings indicate that single cell Raman spectroscopy should be a valuable tool in assessing the quality of sperm cells for in-vitro fertilization.

  4. Microwave and Radio Frequency Workshop

    Broader source: Energy.gov [DOE]

    At the Microwave and Radio Frequency Workshop (held in Long Beach, CA, on July 25, 2012), academic and industry experts discussed the existing and emerging electrotechnologies such as microwave ...

  5. Frequency regulator for synchronous generators

    DOE Patents [OSTI]

    Karlicek, R.F.

    1982-08-10T23:59:59.000Z

    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.

  6. Stepped frequency ground penetrating radar

    DOE Patents [OSTI]

    Vadnais, Kenneth G. (Ojai, CA); Bashforth, Michael B. (Buellton, CA); Lewallen, Tricia S. (Ventura, CA); Nammath, Sharyn R. (Santa Barbara, CA)

    1994-01-01T23:59:59.000Z

    A stepped frequency ground penetrating radar system is described comprising an RF signal generating section capable of producing stepped frequency signals in spaced and equal increments of time and frequency over a preselected bandwidth which serves as a common RF signal source for both a transmit portion and a receive portion of the system. In the transmit portion of the system the signal is processed into in-phase and quadrature signals which are then amplified and then transmitted toward a target. The reflected signals from the target are then received by a receive antenna and mixed with a reference signal from the common RF signal source in a mixer whose output is then fed through a low pass filter. The DC output, after amplification and demodulation, is digitized and converted into a frequency domain signal by a Fast Fourier Transform. A plot of the frequency domain signals from all of the stepped frequencies broadcast toward and received from the target yields information concerning the range (distance) and cross section (size) of the target.

  7. Chapter 19. High Voltage Insulation, Diagnostics and Energetic Electron and Photon Beam Interactions

    E-Print Network [OSTI]

    Chapter 19. High Voltage Insulation, Diagnostics and Energetic Electron and Photon Beam Interactions 19-1 High Voltage Insulation, Diagnostics and Energetic Electron and Photon Beam Interactions 1. DC Properties of Modern Filled Epoxy Insulation Academic and Research Staff Dr. Chathan Cooke Sponsor

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

    E-Print Network [OSTI]

    Tesfatsion, Leigh

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

  9. Wind Farm Reactive Support and Voltage Control Daniel F. Opila Abdi M. Zeynu Ian A. Hiskens

    E-Print Network [OSTI]

    Hiskens, Ian A.

    Wind Farm Reactive Support and Voltage Control Daniel F. Opila Abdi M. Zeynu Ian A. Hiskens Abstract--Wind farms typically contain a variety of voltage control equipment including tap or wind farm; it is desirable to treat all the equipment as an integrated system rather than independent

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

    SciTech Connect (OSTI)

    Not Available

    1994-11-01T23:59:59.000Z

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

  11. High voltage transformers. (Latest citations from the US Patent bibliographic file with exemplary claims). Published Search

    SciTech Connect (OSTI)

    NONE

    1996-08-01T23:59:59.000Z

    The bibliography contains citations of selected patents concerning high voltage transformers. Included are hybrid, video, rectifier, x-ray diagnostic generator, temperature control system, and printed circuit wound high voltage transformers. The fabrication, assembly, and testing of these transformers are also presented. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

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

    SciTech Connect (OSTI)

    NONE

    1995-07-01T23:59:59.000Z

    The bibliography contains citations of selected patents concerning high voltage transformers. Included are hybrid, video, rectifier, x-ray diagnostic generator, temperature control system, and printed circuit wound high voltage transformers. The fabrication, assembly, and testing of these transformers are also presented. (Contains 50-250 citations and includes a subject term index and title list.)

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

    E-Print Network [OSTI]

    John, Lizy Kurian

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

  14. A Voltage Controlled Nano Addressing Circuit University of Texas, San Antonio TX 78249, USA,

    E-Print Network [OSTI]

    Liu, Bao

    A Voltage Controlled Nano Addressing Circuit Bao Liu University of Texas, San Antonio TX 78249, USA, Abstract. A voltage controlled nano addressing circuit is proposed, which (1) improves yield and enables aggressive scaling with no require- ment of precise layout design, (2) achieves precision of addressing

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

    E-Print Network [OSTI]

    2007-01-01T23:59:59.000Z

    Journal of Power Sources 167 (2007) 1117 Voltage reversal during microbial fuel cell stack February 2007; accepted 9 February 2007 Available online 20 February 2007 Abstract Microbial fuel cells Elsevier B.V. All rights reserved. Keywords: Microbial fuel cell; Voltage reversal; Stack; Direct electron

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

    E-Print Network [OSTI]

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

  17. Impact of High Wind Penetration on the Voltage Profile of Distribution Systems

    E-Print Network [OSTI]

    Pota, Himanshu Roy

    of wind generator the voltage of the system may become lower than acceptable voltage level due and wind generator is presented. Simulation results are given in Section III which shows the impact of high--In this paper, simulation results showing the effect of lower and higher penetration of distributed wind

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

    E-Print Network [OSTI]

    Brest, Université de

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

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

    E-Print Network [OSTI]

    Kambhampati, Subbarao

    A LOW POWER SCHEDULING SCHEME WITH RESOURCES OPERATING AT MULTIPLE VOLTAGES Ali Manzak and Chaitali Tempe, AZ 852875706 istanbul@asu.edu, chaitali@asu.edu ABSTRACT This paper presents a new resource the resources operate at multi ple voltages. The scheduling scheme is list based. In each control cycle

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

    E-Print Network [OSTI]

    Liu, Bao

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

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

    E-Print Network [OSTI]

    Pota, Himanshu Roy

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

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

    E-Print Network [OSTI]

    Paris-Sud XI, Universit de

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

  3. Pipeline Strategy for Improving Optimal Energy Efficiency in Ultra-Low Voltage Design

    E-Print Network [OSTI]

    Kambhampati, Subbarao

    Pipeline Strategy for Improving Optimal Energy Efficiency in Ultra-Low Voltage Design Mingoo Seok for the ultra low voltage regime. Based on an analytical model and simulations, we propose a pipelining technique that provides higher energy effi- ciency and performance than conventional approaches to ultra low

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

    E-Print Network [OSTI]

    Paris-Sud XI, Universit de

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

  5. Variation-aware Clock Network Design Methodology for Ultra-Low Voltage (ULV) Circuits

    E-Print Network [OSTI]

    Lim, Sung Kyu

    Variation-aware Clock Network Design Methodology for Ultra-Low Voltage (ULV) Circuits Xin Zhao networks for ultra-low voltage (ULV) circuits. We show that both clock slew and skew play important roles) at comparable or even higher Fmax compared with the existing methods. Keywords--clock network design, ultra-low

  6. Mitigation of Voltage and Current Harmonics in Grid-Connected Microgrids

    E-Print Network [OSTI]

    Vasquez, Juan Carlos

    Mitigation of Voltage and Current Harmonics in Grid-Connected Microgrids Mehdi Savaghebi1 , Josep M-connected microgrids. Two modes of compensation are considered, i.e. voltage and current compensation modes-electronic interface converter to the utility grid or microgrid. Microgrid is a local grid consisting of DGs, energy

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

    E-Print Network [OSTI]

    Zhou, Hai

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

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

    E-Print Network [OSTI]

    Lavaei, Javad

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

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

    E-Print Network [OSTI]

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

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

    E-Print Network [OSTI]

    Hadjicostis, Christoforos

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

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

    E-Print Network [OSTI]

    Cañizares, Claudio A.

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

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

    E-Print Network [OSTI]

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

  13. A New Thermal-Conscious System-Level Methodology for Energy-Efficient Processor Voltage Selection

    E-Print Network [OSTI]

    Wang, Yu

    A New Thermal-Conscious System-Level Methodology for Energy-Efficient Processor Voltage Selection a thermal-conscious system-level methodology to make energy-efficient voltage selection (VS) for nanometer), thermal resistance, are integrated and considered in our system models, and their impacts on energy

  14. Combined effects of gas pressure and exciting frequency on electron energy distribution functions in hydrogen capacitively coupled plasmas

    SciTech Connect (OSTI)

    Abdel-Fattah, E. [Physics Department, Faculty of Science, Zagazig University, Zagazig 44519 (Egypt); Sugai, H. [Department of Electronics and Information Engineering, Chubu University, 1200 Matsumoto-cho, Kasugai 487-8501 (Japan)

    2013-02-15T23:59:59.000Z

    The combined effects of the variation of hydrogen pressure (40-400 mTorr) and exciting frequency (13.56-50 MHz) on the electron energy probability function (EEPF) and other plasma parameters in capacitively coupled hydrogen H{sub 2} discharge at fixed discharge voltage were investigated using rf-compensated Langmuir probe. At a fixed exciting frequency of 13.56 MHz, the EEPF evolved from Maxwellian-like distribution to a bi-Maxwellian distribution when the H{sub 2} pressure increased, possibly due to efficient vibrational excitation. The electron density largely increased to a peak value and then decreased with the increase of H{sub 2} pressure. Meanwhile, the electron temperature and plasma potential significantly decrease and reaching a minimum at 120 mTorr beyond, which saturated or slightly increases. On the other hand, the dissipated power and electron density markedly increased with increasing the exciting frequency at fixed H{sub 2} pressure and voltage. The electron temperatures negligibly dependent on the driving frequency. The EEPFs at low pressure 60 mTorr resemble Maxwellian-like distribution and evolve into a bi-Maxwellian type as frequency increased, due to a collisonless (stochastic) sheath-heating in the very high frequency regime, while the EEPF at hydrogen pressure {>=}120 mTorr retained a bi-Maxwellian-type distribution irrespective of the driving frequency. Such evolution of the EEPFs shape with the driving frequency and hydrogen pressure has been discussed on the basis of electron diffusion processes and low threshold-energy inelastic collision processes taking place in the discharge. The ratio of stochastic power to bulk power heating ratio is dependent on the hydrogen pressure while it is independent on the driving frequency.

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

    DOE Patents [OSTI]

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

    2005-01-04T23:59:59.000Z

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

  16. A theoretical approach for assessing the role of rock and fluid properties in the development of abnormal fluid pressures

    E-Print Network [OSTI]

    Hastings, Thomas Worcester

    1985-01-01T23:59:59.000Z

    A THEORETICAL APPROACH FOR ASSESSING THE ROLE OF ROCK AND FLUID PROPERTIES IN THE DEVELOPMENT OF ABNORMAL FLUID PRESSURES A Thesis by THOMAS WORCESTER HASTINGS Submitted to the Graduate College of Texas ASM University in partial fulfillment... of the requirement for the degree of MASTER OF SCIENCE December 1985 Major Subject: Geology A THEORETICAL APPROACH FOR ASSESSING THE ROLE OF ROCK AND FLUID PROPERTIES IN THE DEVELOPMENT OF ABNORMAL FLUID PRESSURES A Thesis by THOMAS MORCESTER HASTINGS...

  17. High frequency and high wavenumber solar oscillations

    E-Print Network [OSTI]

    H. M. Antia; Sarbani Basu

    1999-02-10T23:59:59.000Z

    We determine the frequencies of solar oscillations covering a wide range of degree (100< l <4000) and frequency (1.5 <\

  18. Sum Frequency Generation for Surface Vibrational Spectroscopy...

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

    Sum Frequency Generation for Surface Vibrational Spectroscopy Sum Frequency Generation for Surface Vibrational Spectroscopy This customized SFG-VS spectrometer incorporates unique...

  19. Variable frequency microprocessor clock generator

    SciTech Connect (OSTI)

    Branson, C.N.

    1989-04-04T23:59:59.000Z

    A microprocessor-based system is described comprising: a digital central microprocessor provided with a clock input and having a rate of operation determined by the frequency of a clock signal input thereto; memory means operably coupled to the central microprocessor for storing programs respectively including a plurality of instructions and addressable by the central microprocessor; peripheral device operably connected to the central microprocessor, the first peripheral device being addressable by the central microprocessor for control thereby; a system clock generator for generating a digital reference clock signal having a reference frequency rate; and frequency rate reduction circuit means connected between the clock generator and the clock input of the central microprocessor for selectively dividing the reference clock signal to generate a microprocessor clock signal as an input to the central microprocessor for clocking the central microprocessor.

  20. H{sup -} beam extraction from a cesium seeded field effect transistor based radio frequency negative hydrogen ion source

    SciTech Connect (OSTI)

    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

    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.