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


1

Nuclear Maintenance Application Center: Dry Type Transformer and Reactor Application and Maintenance Guide  

Science Conference Proceedings (OSTI)

This report is focused on dry-type transformers used in unit secondary substations of nuclear power plants for power delivery purposes. This report does not cover instrument transformers, nor is it specifically for transformers used in grounding circuits, although these usages are addressed in Section 3.The primary purpose of this report is to inform the engineer or technician who has been assigned responsibility for secondary unit substation transformers in a nuclear station’s ...

2012-11-28T23:59:59.000Z

2

LabVIEW with fuzzy logic controller simulation panel for condition monitoring of oil and dry type transformer  

E-Print Network (OSTI)

Abstract—Condition monitoring of electrical power equipment has attracted considerable attention for many years. The aim of this paper is to use Labview with Fuzzy Logic controller to build a simulation system to diagnose transformer faults and monitor its condition. The front panel of the system was designed using LabVIEW to enable computer to act as customer-designed instrument. The dissolved gas-in-oil analysis (DGA) method was used as technique for oil type transformer diagnosis; meanwhile terminal voltages and currents analysis method was used for dry type transformer. Fuzzy Logic was used as expert system that assesses all information keyed in at the front panel to diagnose and predict the condition of the transformer. The outcome of the Fuzzy Logic interpretation will be displayed at front panel of LabVIEW to show the user the conditions of the transformer at any time. Keywords—LabVIEW, Fuzzy Logic, condition monitoring, oil transformer, dry transformer, DGA, terminal values.

N. A. Muhamad; S. A. M. Ali

2006-01-01T23:59:59.000Z

3

Energy-Efficient Dry-Type Distribution Transformers: New Opportunities to Cut Energy Bills and Lock-in Long-Term Energy Savings  

E-Print Network (OSTI)

Nearly 90% of the electricity that powers the industrial sector flows through dry-type distribution transformers. These transformers are very efficient- most convert in excess of 95% of input power to output power. However, because transformers are generally energized 24 hours per day, 365 days per year, even small efficiency improvements can yield big energy and dollar savings for power users. Until now, energy-efficient dry-type transformers have been hard to identify. As a result, most users either have failed to specify efficiency at all or relied on the imperfect indicator of low temperature rise. Most manufactures have not offered an "energy-efficient" product line. Now, the National Electrical Manufacturers' Association (NEMA), the transformer manufacturers' trade association, has published a standard defining energy-efficient transformers. This new standard, NEMA standard TP-1, makes it easier for vendors, specifiers, contractors and end-users to identify and determine the cost-effectiveness of energy-efficient transformers. In addition, some manufacturers are beginning to offer equipment lines specifically designed to meet the energy efficiency levels defined in NEMA standard TP-1.

deLaski, A.; Suozzo, M.

1998-04-01T23:59:59.000Z

4

Plant Engineering: Medium-Voltage Transformer End of Expected Life Guidance  

Science Conference Proceedings (OSTI)

The purpose of this report is to provide guidance to nuclear plant personnel in the determination of the point in life of medium-voltage liquid-immersed and dry-type transformers when long-term planning or contingency planning for the replacement or refurbishment is desirable to preclude end-of-life failure or when preventive maintenance is no longer cost-effective. This report provides recommendations based on historical industry data and subject matter expert (SME) ...

2012-12-12T23:59:59.000Z

5

An Electronic Voltage Transformer Based on WLAN Technology  

Science Conference Proceedings (OSTI)

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

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

2010-03-01T23:59:59.000Z

6

Planar LTCC transformers for high voltage flyback converters.  

SciTech Connect

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

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

2007-06-01T23:59:59.000Z

7

High-voltage air-core pulse transformers  

SciTech Connect

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

Rohwein, G. J.

1981-01-01T23:59:59.000Z

8

Condition Monitoring and Diagnostics of Bushings, Current Transformers, and Voltage Transformers by Oil Analysis  

Science Conference Proceedings (OSTI)

This study was undertaken to determine the merits of oil analysis for condition monitoring and diagnostics of bushings, current, potential and voltage transformers. Oil test results and equipment information from 193 bushings, 830 current transformers, 194 potential transformers and 268 voltage transformers were analyzed. Statistical analyses was used to assigns equipment condition codes from 1 (Normal Operation) to 4 (Extreme) based on threshold limits for dissolved gas in oil results. A more recent set...

2006-12-12T23:59:59.000Z

9

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

E-Print Network (OSTI)

Electric quality problems associated with power interactions between distribution and industrial process control systems can be prevented. Surveys of large users that buy power at the transmission and distribution voltages turn up relatively few complaints about the quality of their incoming power, while surveys of small users connected at secondary voltages tum up numerous complaints about the quality of their incoming power. Three major changes in the characteristics of customer loads and power distribution systems have altered the nature of the power quality equation: (I) greater sensitivity of devices and equipment to electric power variations, (2) the interconnection of sensitive loads in extensive networks and automated processes, and (3) an increase in loads that use power electronics in some type of power conversion configuration [1][2]. This paper presents applications of the constant-voltage transformer (CVT) for mitigating the effects of electric service voltage sags on industrial equipment in an oil refinery. Unlike conventional transformers, the CVT or ferro-resonant transformer allows the core to become saturated with magnetic flux, which maintains a relatively constant output voltage during input voltage variations such as undervoltages, overvoltages, and harmonic distortion.

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

2000-04-01T23:59:59.000Z

10

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

Science Conference Proceedings (OSTI)

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

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

2009-02-01T23:59:59.000Z

11

An accurate continuous calibration system for high voltage current transformer  

SciTech Connect

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

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

2011-02-15T23:59:59.000Z

12

Proceedings: High Voltage Current Transformers and Bushings: Failure Prediction and Prevention Symposium  

Science Conference Proceedings (OSTI)

EPRI-sponsored research has identified key parameters indicative of condition and impending failure of oil-filled, high-voltage current transformers (HVCTs) and bushings. These findings will assist utilities to improve the monitoring of HVCTs and bushings, and to develop mitigation techniques to reduce the risk of catastrophic transformer failure. These proceedings present the results of this research and the experiences of other researchers worldwide.

1999-12-01T23:59:59.000Z

13

A new converter fault discrimination method for a 12-pulse high-voltage direct current system based on wavelet transform and Hidden Markov Models  

Science Conference Proceedings (OSTI)

The progressive development in high-voltage direct current (HVDC) transmission enhances the need to implement an efficient protection scheme to distinguish the minimum faulty part of the system and to relieve the stressed equipment. This paper proposes ... Keywords: Discrete Hidden Markov Models, converter faults, fault discrimination, high-voltage direct current, wavelet transform

Mohamad Tahan; Hassan Monsef; Shahrokh Farhangi

2012-06-01T23:59:59.000Z

14

EPRI Dissolved Gas Analysis Guide for High-Voltage Cables and Transformers  

Science Conference Proceedings (OSTI)

Dissolved gas analysis (DGA) is deemed to be the most economical and reliable diagnostic test for both cables and transformers, and it is finding widespread application worldwide. The general subject of DGA has continued to receive considerable attention for several decades. While there is commonality between cable and transformer DGA and the oil-paper insulating system, there are marked differences with respect to DGA due to the differing designs, materials, and operating conditions associated with ...

2012-12-20T23:59:59.000Z

15

EPRI Dissolved Gas Analysis Guide for High Voltage Cables and Transformers – 2013 Update  

Science Conference Proceedings (OSTI)

Dissolved gas analysis (DGA) is deemed to be an economical and reliable diagnostic test for both cables and transformers and is finding widespread application worldwide. The general subject of DGA has continued to receive considerable attention for several decades. While there is commonality between cable and transformer DGA and the oil-paper insulating system, there are marked differences with respect to DGA due to the differing designs, materials, and operating conditions associated with the two ...

2013-12-20T23:59:59.000Z

16

Tests show ability of vacuum circuit breaker to interrupt fast transient recovery voltage rates of rise of transformer secondary faults  

Science Conference Proceedings (OSTI)

A vacuum circuit breaker demonstrated its ability to interrupt short circuits with faster than normal rates of rise of transient recovery voltage (TRV) at levels greater than those produced by most transformer secondary faults. Two recent exploratory test programs evaluated the interrupting ability of a 15kV vacuum circuit breaker containing interrupters of the rotating arc type with contacts made from a chromium-copper powder metal mixture. The interrupting conditions covered a wide range of currents from 10% to 130% of the 28kA rated short circuit current of the tested circuit breaker and a wide range of TRV rates of rise, including the relatively slow rate of rise, normally used in testing and found in most indoor circuit breaker applications, two faster rates of rise equaling and exceeding those found in a known power plant transformer secondary protection application, and the fastest rates of rise possible in the laboratory which exceed the requirements of most transformer secondary faults. These tests showed that the interrupting performance of the tested vacuum circuit breaker was unaffected by the TRV rate of rise to the fastest rates available in the test lab. Such a vacuum circuit breaker can therefore be used without TRV modifying capacitors to slow down the rate of rise provided by the power system. This ability is particularly important if analysis shows that the expected TRV from a transformer secondary fault has a fast rate of rise beyond the recognized ability of an older circuit breaker to acceptably interrupt.

Smith, R.K. [Westinghouse Science and Technology Center, Pittsburgh, PA (United States)

1995-01-01T23:59:59.000Z

17

PPL: distribution transformer | The Better Buildings Alliance  

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

Plug & Process Loads » Install a Plug & Process Loads » Install a distribution transformer that will reduce energy use by more than 15% using the distribution transformer specification Activities Technology Solutions Teams Lighting & Electrical Space Conditioning Plug & Process Loads Food Service Refrigeration Laboratories Energy Management & Information Systems Public Sector Teams Market Solutions Teams Install a distribution transformer that will reduce energy use by more than 15% using the distribution transformer specification The Plug & Process Loads team developed a low-voltage, dry-type distribution transformer specification that outlines energy-related product requirements. Purchasers can use this document to procure high-efficiency, high-quality products from manufacturers. The specification is unique, as

18

THE COST OF MAINTENANCE TRANSFER UNDER LOAD TAP OF THE TRANSFORMERS POWER OF EXTRA HIGH VOLTAGE THE ELETRONORTE.  

E-Print Network (OSTI)

??In this work a methodology for reduction of maintenance cost in the on-load tap changers (OLTC) of extra high voltage is proposed. The methodology is… (more)

RAIMUNDO NONATO ROSA FILHO

2005-01-01T23:59:59.000Z

19

A Case Study on the Effects of Distribution Line Capacitors on Substation Bus Voltage Regulated with a Load Tap Changing (LTC) Power Transformer: Southern Company Smart Grid Demonstration  

Science Conference Proceedings (OSTI)

This case study describes research to address the adverse effects of distribution capacitors on substation bus voltage with a load-tap-changing (LTC) power transformer. By adding fixed and switched capacitors to the distribution system, Southern Company is able to maintain an efficient distribution grid by providing the reactive power near the end-use devices consuming this power. However, pressure to improve the efficiency of the distribution system has resulted in Southern Company adding a large ...

2013-12-12T23:59:59.000Z

20

Effects of Impulse Voltage Polarity, Peak Amplitude, and Rise Time on Streamers Initiated From a Needle Electrode in Transformer Oil  

E-Print Network (OSTI)

An electrothermal hydrodynamic model is presented to evaluate effects of the applied lightning impulse voltage parameters such as polarity, magnitude, and rise time on the initiation and propagation of the streamers formed ...

Jadidian, Jouya

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


21

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

Science Conference Proceedings (OSTI)

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

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

2009-11-15T23:59:59.000Z

22

Surge voltage suppression in residential power circuits  

Science Conference Proceedings (OSTI)

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

2013-05-17T23:59:59.000Z

23

TRANSFORMATION  

SciTech Connect

Transformation, which alters the genetic makeup of an individual, is a concept that intrigues the human imagination. In Streptococcus pneumoniae such transformation was first demonstrated. Perhaps our fascination with genetics derived from our ancestors observing their own progeny, with its retention and assortment of parental traits, but such interest must have been accelerated after the dawn of agriculture. It was in pea plants that Gregor Mendel in the late 1800s examined inherited traits and found them to be determined by physical elements, or genes, passed from parents to progeny. In our day, the material basis of these genetic determinants was revealed to be DNA by the lowly bacteria, in particular, the pneumococcus. For this species, transformation by free DNA is a sexual process that enables cells to sport new combinations of genes and traits. Genetic transformation of the type found in S. pneumoniae occurs naturally in many species of bacteria (70), but, initially only a few other transformable species were found, namely, Haemophilus influenzae, Neisseria meningitides, Neisseria gonorrheae, and Bacillus subtilis (96). Natural transformation, which requires a set of genes evolved for the purpose, contrasts with artificial transformation, which is accomplished by shocking cells either electrically, as in electroporation, or by ionic and temperature shifts. Although such artificial treatments can introduce very small amounts of DNA into virtually any type of cell, the amounts introduced by natural transformation are a million-fold greater, and S. pneumoniae can take up as much as 10% of its cellular DNA content (40).

LACKS,S.A.

2003-10-09T23:59:59.000Z

24

TRANSFORMER  

DOE Patents (OSTI)

Transformers of a type adapted for use with extreme high power vacuum tubes where current requirements may be of the order of 2,000 to 200,000 amperes are described. The transformer casing has the form of a re-entrant section being extended through an opening in one end of the cylinder to form a coaxial terminal arrangement. A toroidal multi-turn primary winding is disposed within the casing in coaxial relationship therein. In a second embodiment, means are provided for forming the casing as a multi-turn secondary. The transformer is characterized by minimized resistance heating, minimized external magnetic flux, and an economical construction.

Baker, W.R.

1959-08-25T23:59:59.000Z

25

Planning of distribution networks for medium voltage and low voltage.  

E-Print Network (OSTI)

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

Ziari, Iman

2011-01-01T23:59:59.000Z

26

Definition: Automated Voltage Regulators | Open Energy Information  

Open Energy Info (EERE)

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

27

Two terminal line voltage thermostat  

Science Conference Proceedings (OSTI)

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

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

1995-10-10T23:59:59.000Z

28

Lightweight transformer  

DOE Green Energy (OSTI)

The technical effort described in this report relates to the program that was performed to design, fabricate, and test a lightweight transformer for Strategic Defense Initiative Organization (SDIO) mission requirements. The objectives of this program were two-fold: (1) design and fabricate a lightweight transformer using liquid hydrogen as the coolant; and (2) test the completed transformer assembly with a low voltage, dc power source. Although the full power testing with liquid helium was not completed, the program demonstrated the viability of the design approach. The lightweight transformer was designed and fabricated, and low and moderate power testing was completed. The transformer is a liquid hydrogen cooled air core transformer that uses thin copper for its primary and secondary windings. The winding mass was approximately 12 kg, or 0.03 kg/kW. Further refinements of the design to a partial air core transformer could potentially reduce the winding mass to as low as 4 or 5 kg, or 0.0125 kg/kW. No attempt was made on this program to reduce the mass of the related structural components or cryogenic container. 8 refs., 39 figs., 2 tabs.

Swallom, D.W.; Enos, G.

1990-05-01T23:59:59.000Z

29

Interphase power controller with voltage injection  

Science Conference Proceedings (OSTI)

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

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

1994-10-01T23:59:59.000Z

30

TRANSISTOR HIGH VOLTAGE POWER SUPPLY  

DOE Patents (OSTI)

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

Driver, G.E.

1958-07-15T23:59:59.000Z

31

PQ Encyclopedia: Understanding Voltage Unbalance  

Science Conference Proceedings (OSTI)

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

2009-12-11T23:59:59.000Z

32

Appliances and Commercial Equipment Standards  

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

Low-Voltage Dry-Type Distribution Transformers Energy Conservation Standard Low-Voltage Dry-Type Distribution Transformers Energy Conservation Standard Sign up for e-mail updates on regulations for this and other products The Department of Energy (DOE) has completed a rulemaking to amend the current energy conservation standards for liquid-immersed, medium-voltage dry-type, and low-voltage dry-type distribution transformers. This activity is mandated by the Energy Policy and Conservation Act (EPCA). Recent Updates | Public Meeting Information | Submitting Public Comments | Milestones and Documents | Related Rulemakings | Statutory Authority | Contact Information Recent Updates DOE published a final rule regarding amended energy efficiency standards for liquid-immersed, medium-voltage dry-type, and low-voltage dry-type distribution transformers. 78 FR 23335 (April 18, 2013). The distribution transformers final rule was the DOE's first "negotiated rulemaking," conducted under the Federal Advisory Committee Act and the Negotiated Rulemaking Act.

33

U.S. Department of Energy NEPA Categorical Exclusion Determination...  

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

standards in the NOPR include the ERAC-recommended efficiency levels for medium-voltage dry-type transformers and the levels endorsed by DOE's Regulatory Policy Group...

34

HIGH VOLTAGE GENERATOR  

DOE Patents (OSTI)

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

Zito, G.V.

1959-04-21T23:59:59.000Z

35

Definition: Transformer | Open Energy Information  

Open Energy Info (EERE)

Transformer Transformer Jump to: navigation, search Dictionary.png Transformer An electromagnetic device that changes the voltage of alternating current electricity.[1] View on Wikipedia Wikipedia Definition View on Reegle Reegle Definition A transformer consists of a primary- and secondary coil, coupled by a magnetic field. The primary coil induces the voltage in the secondary coil. The voltage transformation depends on the number of windings. Related Terms Electricity, Transmission, Electric grid, transmission lines, electricity generation, transmission line, alternating current References ↑ http://www1.eere.energy.gov/site_administration/glossary.html#T Retrieved LikeLike UnlikeLike You like this.Sign Up to see what your friends like. from "http://en.openei.org/w/index.php?title=Definition:Transformer&oldid=502565

36

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

Science Conference Proceedings (OSTI)

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

Rosli Omar

2010-03-01T23:59:59.000Z

37

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

Science Conference Proceedings (OSTI)

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

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

2010-08-01T23:59:59.000Z

38

Automatic voltage imbalance detector  

DOE Patents (OSTI)

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

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

1984-01-01T23:59:59.000Z

39

Constant voltage ultracapacitor  

Science Conference Proceedings (OSTI)

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

Ezzat G. Bakhoum

2012-01-01T23:59:59.000Z

40

Power Transformer Application for Wind Plant Substations  

Science Conference Proceedings (OSTI)

Wind power plants use power transformers to step plant output from the medium voltage of the collector system to the HV or EHV transmission system voltage. This paper discusses the application of these transformers with regard to the selection of winding configuration, MVA rating, impedance, loss evaluation, on-load tapchanger requirements, and redundancy.

Behnke, M. R. [IEEE PES Wind Plant Collector System Design Working Group; Bloethe, W.G. [IEEE PES Wind Plant Collector System Design Working Group; Bradt, M. [IEEE PES Wind Plant Collector System Design Working Group; Brooks, C. [IEEE PES Wind Plant Collector System Design Working Group; Camm, E H [IEEE PES Wind Plant Collector System Design Working Group; Dilling, W. [IEEE PES Wind Plant Collector System Design Working Group; Goltz, B. [IEEE PES Wind Plant Collector System Design Working Group; Li, J. [IEEE PES Wind Plant Collector System Design Working Group; Niemira, J. [IEEE PES Wind Plant Collector System Design Working Group; Nuckles, K. [IEEE PES Wind Plant Collector System Design Working Group; Patino, J. [IEEE PES Wind Plant Collector System Design Working Group; Reza, M [IEEE PES Wind Plant Collector System Design Working Group; Richardson, B. [IEEE PES Wind Plant Collector System Design Working Group; Samaan, N. [IEEE PES Wind Plant Collector System Design Working Group; Schoene, Jens [IEEE PES Wind Plant Collector System Design Working Group; Smith, Travis M [ORNL; Snyder, Isabelle B [ORNL; Starke, Michael R [ORNL; Walling, R. [IEEE PES Wind Plant Collector System Design Working Group; Zahalka, G. [IEEE PES Wind Plant Collector System Design Working Group

2010-01-01T23:59:59.000Z

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


41

Real-time static voltage scaling on multiprocessors  

Science Conference Proceedings (OSTI)

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

Kenji Funaoka; Shinpei Kato; Nobuyuki Yamasaki

2007-11-01T23:59:59.000Z

42

Optical voltage reference  

DOE Patents (OSTI)

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

Rankin, R.; Kotter, D.

1994-04-26T23:59:59.000Z

43

Optical voltage reference  

DOE Patents (OSTI)

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

Rankin, R.; Kotter, D.

1992-12-31T23:59:59.000Z

44

Automated Voltage Standard Ready  

Science Conference Proceedings (OSTI)

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

2013-04-08T23:59:59.000Z

45

Power Transformer Failure Investigation and Root Cause Analysis  

Science Conference Proceedings (OSTI)

This report provides practical, step-by-step guidance to help utility personnel gather evidence and perform investigations on failed or retired high-voltage substation power transformers to assist in determining the cause of the transformer’s failure or the service condition of retired units.BackgroundHigh-voltage transformers are essential to the reliability of the power system, but many are aging and nearing the end of their design lives. Transformer ...

2012-12-12T23:59:59.000Z

46

Voltage Quality Improvement Using DVR  

Science Conference Proceedings (OSTI)

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

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

2010-03-01T23:59:59.000Z

47

Voltage balanced multilevel voltage source converter system  

SciTech Connect

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

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

1997-01-01T23:59:59.000Z

48

Voltage balanced multilevel voltage source converter system  

SciTech Connect

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

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

1997-07-01T23:59:59.000Z

49

Triple voltage dc-to-dc converter and method  

DOE Patents (OSTI)

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

Su, Gui-Jia (Knoxville, TN)

2008-08-05T23:59:59.000Z

50

Substation voltage upgrading  

SciTech Connect

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

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

1989-08-01T23:59:59.000Z

51

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

Science Conference Proceedings (OSTI)

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

52

High voltage DC power supply  

DOE Patents (OSTI)

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

Droege, T.F.

1989-12-19T23:59:59.000Z

53

? Adjustable Output Voltage  

E-Print Network (OSTI)

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

Lmq Is Aec-q Grade

2008-01-01T23:59:59.000Z

54

Low-voltage gyrotrons  

SciTech Connect

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

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

2013-03-15T23:59:59.000Z

55

Comparative High Voltage Impulse Measurement  

Science Conference Proceedings (OSTI)

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

2013-04-19T23:59:59.000Z

56

High voltage electrical amplifier having a short rise time  

DOE Patents (OSTI)

A circuit, comprising an amplifier and a transformer is disclosed that produces a high power pulse having a fast response time, and that responds to a digital control signal applied through a digital-to-analog converter. The present invention is suitable for driving a component such as an electro-optic modulator with a voltage in the kilovolt range. The circuit is stable at high frequencies and during pulse transients, and its impedance matching circuit matches the load impedance with the output impedance. The preferred embodiment comprises an input stage compatible with high-speed semiconductor components for amplifying the voltage of the input control signal, a buffer for isolating the input stage from the output stage; and a plurality of current amplifiers connected to the buffer. Each current amplifier is connected to a field effect transistor (FET), which switches a high voltage power supply to a transformer which then provides an output terminal for driving a load. The transformer comprises a plurality of transmission lines connected to the FETs and the load. The transformer changes the impedance and the voltage of the output. The preferred embodiment also comprises a low voltage power supply for biasing the FETs at or near an operational voltage. 8 figs.

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

1989-12-07T23:59:59.000Z

57

High voltage electrical amplifier having a short rise time  

DOE Patents (OSTI)

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

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

1991-01-01T23:59:59.000Z

58

Partial core pulse transformer  

DOE Patents (OSTI)

A light-weight partial-core pule transformer is provided for generating high voltage output pulses with low distortion. The transformer includes sets of ferrite bars arranged so as to extend longitudinally along the inside and outside surfaces of a high frequency cylindrical coil winding-pair. The ferrite bars are arranged in pairs with the bars of each pair being located on opposite sides of winding-pair. The bars are preferably disposed in a radially symmetric arrangement around the winding-pair, and each has a length at least equal to the width of the winding-pair.

Lawson, R.N.; Rohwein, G.J.

1991-12-31T23:59:59.000Z

59

Device for monitoring cell voltage  

SciTech Connect

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

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

2012-08-21T23:59:59.000Z

60

Electron launching voltage monitor  

DOE Patents (OSTI)

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

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

1992-01-01T23:59:59.000Z

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


61

Voltage controlled current source  

DOE Patents (OSTI)

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

Casne, Gregory M. (Pittsburgh, PA)

1992-01-01T23:59:59.000Z

62

High frequency breakdown voltage  

SciTech Connect

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

Chu, Thanh Duy

1992-03-01T23:59:59.000Z

63

Power quality assessment of specially connected transformers  

Science Conference Proceedings (OSTI)

This paper examines and compares the voltage deviation, voltage unbalance, and harmonic distortion of V-V, Scott, and Le Blanc connected transformers by a novel approach. The power quality factors are needed to truly reflect the loading characteristics ... Keywords: Le Blanc connection, V-V connection, power quality, scott connection

Yao-Hung Chan; Chi-Jui Wu; Shu-Chen Wang

2010-04-01T23:59:59.000Z

64

Definition: Automated Voltage And Var Control | Open Energy Information  

Open Energy Info (EERE)

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

65

E-beam high voltage switching power supply  

DOE Patents (OSTI)

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

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

1996-01-01T23:59:59.000Z

66

E-beam high voltage switching power supply  

DOE Patents (OSTI)

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

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

1996-10-15T23:59:59.000Z

67

Appell Transformation and Canonical Transforms  

E-Print Network (OSTI)

The interpretation of the optical Appell transformation, as previously elaborated in relation to the free-space paraxial propagation under both a rectangular and a circular cylindrical symmetry, is reviewed. Then, the caloric Appell transformation, well known in the theory of heat equation, is shown to be amenable for a similar interpretation involving the Laplace transform rather than the Fourier transform, when dealing with the 1D heat equation. Accordingly, when considering the radial heat equation, suitably defined Hankel-type transforms come to be involved in the inherent Appell transformation. The analysis is aimed at outlining the link between the Appell transformation and the canonical transforms.

Torre, Amalia

2011-01-01T23:59:59.000Z

68

Riesz transforms for Dunkl transform  

E-Print Network (OSTI)

In this paper we obtain the $L^p$-boundedness of Riesz transforms for Dunkl transform for all $1

Amri, Béchir

2011-01-01T23:59:59.000Z

69

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

DOE Patents (OSTI)

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

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

1995-01-01T23:59:59.000Z

70

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

DOE Patents (OSTI)

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

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

1995-05-23T23:59:59.000Z

71

PRESENT AND FUTURE TECHNOLOGY OF HIGH VOLTAGE SYSTEMS FOR NEUTRAL BEAM INJECTORS  

E-Print Network (OSTI)

savings tn the power conditioning transformers would result.power supply would be extremely simple, involving as major components only primary contactors, voltage-variable transformer,transformer reactance. For the LBL 160-kV, 75-A NBSTF Accel power

Baker, W.R.

2011-01-01T23:59:59.000Z

72

High voltage pulse conditioning  

DOE Patents (OSTI)

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

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

1989-02-21T23:59:59.000Z

73

High voltage pulse conditioning  

DOE Patents (OSTI)

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

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

1990-01-01T23:59:59.000Z

74

HIGH VOLTAGE GENERATOR  

DOE Patents (OSTI)

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

Schwemin, A.J.

1959-03-17T23:59:59.000Z

75

HIGH VOLTAGE GENERATOR  

DOE Patents (OSTI)

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

Schwemin, A.J.

1959-03-17T23:59:59.000Z

76

HIGH VOLTAGE ION SOURCE  

DOE Patents (OSTI)

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

Luce, J.S.

1960-04-19T23:59:59.000Z

77

Integral transformation and Darboux transformation  

E-Print Network (OSTI)

We review Darboux-Crum transformation of Heun's differential equation. By rewriting an integral transformation of Heun's differential equation into a form of elliptic functions, we see that the integral representation is a generalization of Darboux-Crum transformation. We also consider conservation of monodromy with respect to the transformations.

Takemura, Kouichi

2009-01-01T23:59:59.000Z

78

High voltage variable diameter insulator  

DOE Patents (OSTI)

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

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

1984-01-01T23:59:59.000Z

79

Automatic voltage-imbalance detector  

DOE Patents (OSTI)

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

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

1981-05-20T23:59:59.000Z

80

Testability Transformation  

E-Print Network (OSTI)

A testability transformation is a source-to-source transformation that aims to improve the ability of a given test generation method to generate test data for the original program. This paper

Mark Harman; Lin Hu; Robert Hierons; Joachim Wegener; Harmen Sthamer; Andre Baresel; Marc Roper

2004-01-01T23:59:59.000Z

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


81

Market Transformation  

DOE Green Energy (OSTI)

Summarizes the goals and activities of the DOE Solar Energy Technologies Program efforts within its market transformation subprogram.

Not Available

2008-09-01T23:59:59.000Z

82

A novel control strategy for dynamic voltage restorer using decoupled multiple reference frame PLL (DMRF-PLL)  

Science Conference Proceedings (OSTI)

This paper presents a new control scheme for dynamic voltage restorer (DVR), which consists of a set of series and shunt converters connected back-to-back (BTB), three series transformers, and a dc capacitor installed on the common dc-link. The DVR is ... Keywords: dc capacitor control, decoupled multiple reference frame phase locked loop (DMRF-PLL), dynamic voltage restorer, harmonic and unbalanced voltage compensation, series converters, shunt converters, voltage sag detection

Lin Xu; Yang Han; M. M. Khan; Lidan Zhou; Gang Yao; Chen Chen; Jumin Pan

2009-02-01T23:59:59.000Z

83

Engineering Technical Training Modules - Medium Voltage System Protection and Coordination Version 1.0  

Science Conference Proceedings (OSTI)

The purpose of this training module is to provide a basic understanding of protective relaying and coordination typically provided for medium voltage power systems. This module provides a discussion on current and potential transformers, the protective relays typically used as well as considerations for equipment protection and coordination or selective tripping. Medium voltage motor, transformer, and bus protection applications are covered. Lesson 4 focuses on emergency diesel generator protection in n...

2011-08-09T23:59:59.000Z

84

Nonferromagnetic linear variable differential transformer  

DOE Patents (OSTI)

A nonferromagnetic linear variable differential transformer for accurately measuring mechanical displacements in the presence of high magnetic fields is provided. The device utilizes a movable primary coil inside a fixed secondary coil that consists of two series-opposed windings. Operation is such that the secondary output voltage is maintained in phase (depending on polarity) with the primary voltage. The transducer is well-suited to long cable runs and is useful for measuring small displacements in the presence of high or alternating magnetic fields.

Ellis, James F. (Powell, TN); Walstrom, Peter L. (Oak Ridge, TN)

1977-06-14T23:59:59.000Z

85

Robust Policies for the Transformer Acquisition and Allocation Problem  

E-Print Network (OSTI)

;Abstract As the electric transmission system in the U.S. ages, mitigating the risk of high-voltage trans of historical data. A number of authors have tackled issues of transformer allocation. Chowdhury and Koval (2005 transformer hazard rate curves. In Enders et al. (2007) we explore the locational aspects of transformer

Powell, Warren B.

86

A Calibration Service for Voltage Transformers and High ...  

Science Conference Proceedings (OSTI)

Page 1. Page 2. Page 3. Page 4. Page 5. Page 6. Page 7. Page 8. Page 9. Page 10. Page 11. Page 12. Page 13. Page 14. Page 15. Page 16. Page ...

2012-10-22T23:59:59.000Z

87

High voltage feedthrough bushing  

DOE Patents (OSTI)

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

Brucker, J.P.

1991-12-31T23:59:59.000Z

88

Substation voltage upgrading  

SciTech Connect

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

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

1992-04-01T23:59:59.000Z

89

Voltage Vehicles | Open Energy Information  

Open Energy Info (EERE)

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

90

Humidity, Temperature, and Voltage (Presentation)  

SciTech Connect

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

Wohlgemuth, J.

2012-03-01T23:59:59.000Z

91

Market Transformation  

Fuel Cell Technologies Publication and Product Library (EERE)

This Fuel Cell Technologies Program fact sheet outlines current status and challenges in the market transformation of hydrogen and fuel cell technologies.

92

KSI's Cross Insulated Core Transformer Technology  

Science Conference Proceedings (OSTI)

Cross Insulated Core Transformer (CCT) technology improves on Insulated Core Transformer (ICT) implementations. ICT systems are widely used in very high voltage, high power, power supply systems. In an ICT transformer ferrite core sections are insulated from their neighboring ferrite cores. Flux leakage is present at each of these insulated gaps. The flux loss is raised to the power of stages in the ICT design causing output voltage efficiency to taper off with increasing stages. KSI's CCT technology utilizes a patented technique to compensate the flux loss at each stage of an ICT system. Design equations to calculate the flux compensation capacitor value are presented. CCT provides corona free operation of the HV stack. KSI's CCT based High Voltage power supply systems offer high efficiency operation, high frequency switching, low stored energy and smaller size over comparable ICT systems.

Uhmeyer, Uwe [Kaiser Systems, Inc, 126 Sohier Road, Beverly, MA 01915 (United States)

2009-08-04T23:59:59.000Z

93

Strain-optic voltage monitor  

DOE Patents (OSTI)

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

Weiss, J.D.

1995-12-31T23:59:59.000Z

94

E-beam high voltage switching power supply  

DOE Patents (OSTI)

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

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

1997-01-01T23:59:59.000Z

95

E-beam high voltage switching power supply  

DOE Patents (OSTI)

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

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

1997-03-11T23:59:59.000Z

96

Electrokinetic effects in power transformers  

Science Conference Proceedings (OSTI)

Electrokinetic effects such as static electrification can cause catastrophic failures in large forced-oil-cooled power transformers. Experimental and analytical studies confirm that surface charges can significantly impact dielectric integrity. The project team used a closed-loop oil circulation system and full-scale models of power transformer cooling duct structures to conduct controlled experiments. They measured charge density in the oil-resulting from flow through these structures-as a function of flow rate, temperature, ac voltage stress, moisture, and duct types. In addition, they constructed models so that the spatial distribution of electrostatically induced currents and stresses could be determined. They developed a finite-element computer program to study the complex voltage distribution in the models and in two transformer winding examples. A special test cell was used to examine the impact of surface charge on creep strength of transformer pressboard. Static electrification in power transformer duct structures is aggravated by flow rate, temperature, presence of collars, and ac energization; and it is mitigated by increasing oil moisture content. Shell-form model structures exhibit more charge generation than disk-type core-form winding ducts under corresponding conditions. Partial discharges were detected in one shell-form model but only under the worst conditions. These discharges were not energetic enough to produce visible damage. Preliminary finite-element analysis indicates that surface charge has more impact on cumulative stress in a shell-form geometry than in a core-form disk winding.

Nelson, J.K.; Lee, M.J.; Salon, S.J. (Rensselaer Polytechnic Inst., Troy, NY (United States). Dept. of Electric Power Engineering)

1992-11-01T23:59:59.000Z

97

Analysis of parametric transformer with rectifier load  

SciTech Connect

This paper describes a push-pull parametric transformer constructed using a pair of orthogonal-cores. The operating characteristics of the parametric transformer with a rectifier load were analyzed based on SPICE simulations. The analysis results show good agreement with experiment. It was found that the input surge current of the full-wave rectifier circuit with a smoothing capacitor can be compensated by the parametric transformer. Use of the parametric transformer as a power stabilizer is anticipated owing to its various functions such as for voltage regulation and overload protection.

Ichinokura, O.; Jinzenji, T. (Tohoku Univ., Sendai (Japan)); Tajima, K. (Akita Univ. (Japan))

1993-03-01T23:59:59.000Z

98

Transformer current sensor for superconducting magnetic coils  

DOE Patents (OSTI)

The present invention is a current transformer for operating currents larger than 2kA (two kiloamps) that is capable of detecting a millivolt level resistive voltage in the presence of a large inductive voltage. Specifically, the present invention includes substantially cylindrical primary turns arranged to carry a primary current and substantially cylindrical secondary turns arranged coaxially with and only partially within the primary turns, the secondary turns including an active winding and a dummy winding, the active and dummy windings being coaxial, longitudinally separated and arranged to mutually cancel voltages excited by commonly experienced magnetic fields, the active winding but not the dummy winding being arranged within the primary turns.

Shen, S.S.; Wilson, C.T.

1985-04-16T23:59:59.000Z

99

Transformer Efficiency Assessment - Okinawa, Japan  

Science Conference Proceedings (OSTI)

The US Army Engineering & Support Center, Huntsville (USAESCH), and the US Marine Corps Base (MCB), Okinawa, Japan retained Idaho National Laboratory (INL) to conduct a Transformer Efficiency Assessment of “key” transformers located at multiple military bases in Okinawa, Japan. The purpose of this assessment is to support the Marine Corps Base, Okinawa in evaluating medium voltage distribution transformers for potential efficiency upgrades. The original scope of work included the MCB providing actual transformer nameplate data, manufacturer’s factory test sheets, electrical system data (kWh), demand data (kWd), power factor data, and electricity cost data. Unfortunately, the MCB’s actual data is not available and therefore making it necessary to de-scope the original assessment. Note: Any similar nameplate data, photos of similar transformer nameplates, and basic electrical details from one-line drawings (provided by MCB) are not a replacement for actual load loss test data. It is recommended that load measurements are performed on the high and low sides of transformers to better quantify actual load losses, demand data, and power factor data. We also recommend that actual data, when available, be inserted by MCB Okinawa where assumptions have been made and then the LCC analysis updated. This report covers a generalized assessment of modern U.S. transformers in a three level efficiency category, Low-Level efficiency, Medium-Level efficiency, and High-Level efficiency.

Thomas L. Baldwin; Robert J. Turk; Kurt S. Myers; Jake P. Gentle; Jason W. Bush

2012-08-01T23:59:59.000Z

100

Transformer Efficiency Assessment - Okinawa, Japan  

SciTech Connect

The US Army Engineering & Support Center, Huntsville (USAESCH), and the US Marine Corps Base (MCB), Okinawa, Japan retained Idaho National Laboratory (INL) to conduct a Transformer Efficiency Assessment of “key” transformers located at multiple military bases in Okinawa, Japan. The purpose of this assessment is to support the Marine Corps Base, Okinawa in evaluating medium voltage distribution transformers for potential efficiency upgrades. The original scope of work included the MCB providing actual transformer nameplate data, manufacturer’s factory test sheets, electrical system data (kWh), demand data (kWd), power factor data, and electricity cost data. Unfortunately, the MCB’s actual data is not available and therefore making it necessary to de-scope the original assessment. Note: Any similar nameplate data, photos of similar transformer nameplates, and basic electrical details from one-line drawings (provided by MCB) are not a replacement for actual load loss test data. It is recommended that load measurements are performed on the high and low sides of transformers to better quantify actual load losses, demand data, and power factor data. We also recommend that actual data, when available, be inserted by MCB Okinawa where assumptions have been made and then the LCC analysis updated. This report covers a generalized assessment of modern U.S. transformers in a three level efficiency category, Low-Level efficiency, Medium-Level efficiency, and High-Level efficiency.

Thomas L. Baldwin; Robert J. Turk; Kurt S. Myers; Jake P. Gentle; Jason W. Bush

2012-05-01T23:59:59.000Z

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


101

Transformative copy  

E-Print Network (OSTI)

The ability to create an unlimited number of identical copies is a privilege of digital documents. What if that would not be the case, if each copy of a digital file would go along with some sort of transformation? This ...

Offenhuber, Dietmar

2008-01-01T23:59:59.000Z

102

Utility Direct Medium Voltage DC Fast Charger Update: DC Fast Charger Characterization  

Science Conference Proceedings (OSTI)

EPRI developed a fact charging technology for electric vehicles based on a solid state transformer technology known as the Intelligent Universal Transformer (IUT). The IUT technology replaces both the independent power conversion units as well as the conventional transformer with a single interface system which can be used for fast charging of electric vehicles. The versatility of the IUT provides an intermediate DC bus voltage at the 400-V level that can be directly used for a DC distribution ...

2012-12-31T23:59:59.000Z

103

High-voltage-compatible, fully depleted CCDs  

E-Print Network (OSTI)

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

2006-01-01T23:59:59.000Z

104

Chapter 4 - Understanding Voltage Sags  

Science Conference Proceedings (OSTI)

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

2005-12-31T23:59:59.000Z

105

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

Science Conference Proceedings (OSTI)

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

Palaparthi Ananthababu; Burle Trinadha; K. Ram Charan

2009-12-01T23:59:59.000Z

106

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

Science Conference Proceedings (OSTI)

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

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

2008-12-01T23:59:59.000Z

107

Definition: Phase Angle Regulating Transformer | Open Energy Information  

Open Energy Info (EERE)

Angle Regulating Transformer Angle Regulating Transformer Jump to: navigation, search Dictionary.png Phase Angle Regulating Transformer Transformers that enable phase-angle control between the primary (source) and the secondary (load) side to create a phase shift between the primary side voltage and the secondary side voltage. The purpose of this phase shift is to control the real power flow through interconnected power systems.[1] Also Known As phase angle regulating transformers (PARs) Related Terms transformer, real power, smart grid References ↑ [www.smartgrid.gov/sites/default/files/pdfs/description_of_assets.pdf SmartGrid.gov 'Description of Assets'] An in LikeLike UnlikeLike You like this.Sign Up to see what your friends like. line Glossary Definition Retrieved from "http://en.openei.org/w/index.php?title=Definition:Phase_Angle_Regulating_Transformer&oldid=502556"

108

Substantial Transformation  

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

4 4 Recovery Act/Buy American Information Related to Substantial Transformation GUIDANCE ON MANUFACTURED GOODS AND SUBSTANTIAL TRANSFORMATION FOR FINANCIAL ASSISTANCE AWARDS Section 1605 of the Recovery Act states, "None of the funds appropriated or otherwise made available by this Act may be used for a project for the construction, alteration, maintenance, or repair of a public building or public work unless all of the iron, steel, and manufactured goods used in the project are produced in the United States." The Office of Management and Budget's (OMB) guidance on implementing this section defines "manufactured good" as a "good brought to the construction site for incorporation into

109

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

E-Print Network (OSTI)

PAPER ACCEPTED TO IEEE TRANSACTIONS ON POWER SYSTEMS, Nov. 2008 1 Reactive Power and Voltage) problem associated with reactive power and voltage control in distribution systems to minimize daily on the number of switching operations of transformer load tap changers (LTCs) and capacitors, which are modeled

Cañizares, Claudio A.

110

Automated Voltage Control in LHCb  

E-Print Network (OSTI)

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

Granado Cardoso, L; Jacobsson, R

2011-01-01T23:59:59.000Z

111

Appliances and Commercial Equipment Standards  

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

Liquid-Immersed and Medium-Voltage Dry-type Distribution Transformers Energy Conservation Standard Liquid-Immersed and Medium-Voltage Dry-type Distribution Transformers Energy Conservation Standard Sign up for e-mail updates on regulations for this and other products The Department of Energy (DOE) has completed a rulemaking to amend the current energy conservation standards for liquid-immersed, medium voltage dry-type, and low-voltage dry-type distribution transformers. This activity is mandated by the Energy Policy and Conservation Act (EPCA). Recent Updates | Public Meeting Information | Submitting Public Comments | Milestones and Documents | Related Rulemakings | Statutory Authority | Contact Information Recent Updates DOE published a final rule regarding amended energy efficiency standards for liquid-immersed, medium-voltage dry-type, and low-voltage dry-type distribution transformers. 78 FR 23335 (April 18, 2013). The distribution transformers final rule was the DOE's first "negotiated rulemaking," conducted under the Federal Advisory Committee Act and the Negotiated Rulemaking Act.

112

Appliances and Commercial Equipment Standards  

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

Distribution Transformers Distribution Transformers Sign up for e-mail updates on regulations for this and other products A distribution transformer provides the final voltage transformation in the electric power distribution system by reducing the high voltage of electric current from a power line to a lower voltage for use in a building. The Department of Energy (DOE) has regulated the energy efficiency level of low-voltage dry-type distribution transformers since 2007, and liquid-immersed and medium-voltage dry-type distribution transformers since 2010. A distribution transformer designed and constructed to be mounted on a utility pole is referred to as a pole-mount transformer. A distribution transformer designed and constructed to be located at ground level or underground, mounted on a concrete pad, and locked in a steel case is referred to as a pad-mount transformer.

113

Portec Voltage Regulators: for Emergency Diesel Generators  

Science Conference Proceedings (OSTI)

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

2004-12-15T23:59:59.000Z

114

Power Transformer Failure Investigation and Root Cause Analysis  

Science Conference Proceedings (OSTI)

This report provides practical, step-by-step guidance to help utility personnel gather evidence and perform investigations on failed or retired high-voltage substation power transformers to assist in determining the cause of the transformer failure or the service condition of retired units.

2011-12-21T23:59:59.000Z

115

Power Transformer Failure Investigation and Root Cause Analysis  

Science Conference Proceedings (OSTI)

This report provides practical, step-by-step guidance to help utility personnel gather evidence and perform investigations on failed or retired high-voltage substation power transformers to assist in determining the cause of the transformer failure or the service condition of retired units.

2010-12-23T23:59:59.000Z

116

Testing and Error Analysis of Acceleration of Rotating Transformer  

Science Conference Proceedings (OSTI)

From the working principle of rotary transformers, the paper in-depth analyses the relationship between output voltage and rotor angle as well as speed. By using the method of series expansion and discrete, angular acceleration formula which is used ... Keywords: Rotating Transformer, Acceleration, Error of Measurement, slip frequency

Lu Xiuhe; Xue Peng

2010-07-01T23:59:59.000Z

117

Fiber-optic voltage sensor  

DOE Patents (OSTI)

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

Wood, C.B.

1990-12-31T23:59:59.000Z

118

A voltage controlled current source  

DOE Patents (OSTI)

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

Casne, G.M.

1990-12-21T23:59:59.000Z

119

Fiber-optic voltage sensor  

DOE Patents (OSTI)

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

Wood, C.B.

1990-01-01T23:59:59.000Z

120

Ancillary service details: Voltage control  

SciTech Connect

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

Kirby, B.; Hirst, E.

1997-12-01T23:59:59.000Z

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


121

Probabilistic voltage assessment and VAR compensation  

SciTech Connect

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

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

1988-01-01T23:59:59.000Z

122

RF transformer  

DOE Patents (OSTI)

There is provided an improved RF transformer having a single-turn secondary of cylindrical shape and a coiled encapsulated primary contained within the secondary. The coil is tapered so that the narrowest separation between the primary and the secondary is at one end of the coil. The encapsulated primary is removable from the secondary so that a variety of different capacity primaries can be utilized with one secondary.

Smith, James L. (Naperville, IL); Helenberg, Harold W. (Calumet City, IL); Kilsdonk, Dennis J. (Joliet, IL)

1979-01-01T23:59:59.000Z

123

A method for reducing harmonics in output voltages of a double-connected inverter  

SciTech Connect

A new method for reducing harmonics involved in output voltages of the double-connected inverter is proposed. By adding four auxiliary switching devices and an interphase transformer with secondary winding to the conventional 12-step inverter, output voltages of the proposed circuit can be almost the same waveforms as a conventional 36-step inverter. In this paper, circuit performances and output voltage waveforms are discussed, and the optimum parameters are derived. Then, effects on harmonic reductions can be clarified by theoretical and experimental results, and ratings of system components are investigated.

Masukawa, Shigeo; Iida, Shoji (Tokyo Denki Univ., Tokyo (Japan). Dept. of Electrical Engineering)

1994-09-01T23:59:59.000Z

124

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

DOE Patents (OSTI)

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

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

1993-01-19T23:59:59.000Z

125

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

SciTech Connect

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

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

2009-05-01T23:59:59.000Z

126

Lorentz Transformations  

E-Print Network (OSTI)

This paper describes a particularly didactic and transparent derivation of basic properties of the Lorentz group. The generators for rotations and boosts along an arbitrary direction, as well as their commutation relations, are written as functions of the unit vectors that define the axis of rotation or the direction of the boost (an approach that can be compared with the one that in electrodynamics, works with the electric and magnetic fields instead of the Maxwell stress tensor). For finite values of the angle of rotation or the boost's velocity, collectively denoted by V, the existence of an exponential expansion for the coordinate transformation's matrix, M (in terms of GV where G is the generator) requires that the matrix's derivative with respect to V, be equal to GM. This condition can only be satisfied if the transformation is additive as it is indeed the case for rotations, but not for velocities. If it is assumed, however, that for boosts such an expansion exists, with V = V(v), v being the velocity, and if the above condition is imposed on the boost's matrix then its expression in terms of hyperbolic cosh(V) and sinh(V} is recovered, and the expression for V(= arc tanh(v)) is determined. A general Lorentz transformation can be written as an exponential containing the sum of a rotation and a boost, which to first order is equal to the product of a boost with a rotation. The calculations of the second and third order terms show that the equations for the generators used in this paper, allow to reliably infer the expressions for the higher order generators, without having recourse to the commutation relations. The transformationmatrices for Weyl spinors are derived for finite values of the rotation and velocity, and field representations, leading to the expression for the angular momentum operator, are studied.

Bernard R. Durney

2011-03-01T23:59:59.000Z

127

TRANSFORMER APPARATUS  

DOE Patents (OSTI)

Transformer apparatus is designed for measuring the amount of a paramagnetic substance dissolved or suspended in a diamagnetic liquid. The apparatus consists of a cluster of tubes, some of which are closed and have sealed within the diamagnetic substance without any of the paramagnetic material. The remaining tubes are open to flow of the mix- ture. Primary and secondary conductors are wrapped around the tubes in such a way as to cancel noise components and also to produce a differential signal on the secondaries based upon variations of the content of the paramagnetic material. (AEC)

Wolfgang, F.; Nicol, J.

1962-11-01T23:59:59.000Z

128

High voltage photovoltaic power converter  

DOE Patents (OSTI)

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

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

2001-01-01T23:59:59.000Z

129

Evaluating Transformer Losses  

E-Print Network (OSTI)

This paper outlines how to determine what transformer losses cost and how to evaluate transformer bids to optimize the investment.

Grun, R. L. Jr.

1989-09-01T23:59:59.000Z

130

Development of a New Multilevel Converter-Based Intelligent Universal Transformer: Design Analysis  

Science Conference Proceedings (OSTI)

This report provides a comprehensive design analysis of a high-voltage multilevel converter-based intelligent universal transformer (IUT). The proposed IUT design includes back-to-back, interconnected, multi-level converters coupled to a switched inverter circuit via a high-frequency transformer. The input of the universal transformer can be coupled to a high-voltage distribution system such as 4.16-kV with the use of existing high-voltage silicon insulated-gate bipolar transistor (IGBT) devices, and the...

2004-03-29T23:59:59.000Z

131

HIGH VOLTAGE TERMINAL IN COSY ELECTRON COOLER V.A. Chekavinskiy, E.A. Bekhtenev, I.A. Gusev, M.N. Kondaurov, V.R. Kozak, E.A. Kuper, V.R.  

E-Print Network (OSTI)

, and powered by multistage transformer, capable of 15 kW power at 26 kHz. Wireless control is passed through high voltage circumstances. Powering of HVT electronics is provided by cascade transformer acceleration system ­ high voltage terminal. All power and control electronics were placed in a single isolated

Kozak, Victor R.

132

Voltage unbalance effects on induction motor performance  

Science Conference Proceedings (OSTI)

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

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

2006-09-01T23:59:59.000Z

133

Light-weight DC to very high voltage DC converter  

DOE Patents (OSTI)

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

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

1998-01-01T23:59:59.000Z

134

Light-weight DC to very high voltage DC converter  

DOE Patents (OSTI)

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

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

1998-06-30T23:59:59.000Z

135

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

Science Conference Proceedings (OSTI)

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

P. Beneš; J. Fo?t; M. Pittermann

2011-09-01T23:59:59.000Z

136

High voltage RF feedthrough bushing  

DOE Patents (OSTI)

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

Grotz, Glenn F. (Huntington Station, NY)

1984-01-01T23:59:59.000Z

137

Cost of Providing Ancillary Services from Power Plants: Reactive Supply and Voltage Control  

Science Conference Proceedings (OSTI)

This report provides a methodology for determining the variable costs of generating and supplying reactive power to a transmission system, via the generator step-up transformer, for system voltage control. The report examines the costs of additional energy losses, maintenance, repair, and plant aging associated with the generation of reactive power. TR-107270-V3SI contains System of International units.

1997-09-02T23:59:59.000Z

138

Design, Development and Testing of a DSP Based Dynamic Voltage Restorer  

Science Conference Proceedings (OSTI)

The paper describes the design, development and testing of a three phase prototype Voltage Source Inverter (VSI) as part of the Superconducting Magnetic Energy Storage (SMES) system technology development at Variable Energy Cyclotron Centre (VECC), Kolkata. ... Keywords: SMES, DSC, LC filter, Injection Transformer, Space Vector PWM, Software PLL

A. De, S. Kumari, V. K. Khare, S. S. Pal, A. Sadhukhan, V. K. Meshram, S. K. Thakur, S. Saha

2012-12-01T23:59:59.000Z

139

Low power, scalable multichannel high voltage controller  

DOE Patents (OSTI)

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

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

2006-03-14T23:59:59.000Z

140

Low power, scalable multichannel high voltage controller  

DOE Patents (OSTI)

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

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

2008-03-25T23:59:59.000Z

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


141

Dynamic Voltage Regulation Using Distributed Energy Resources  

Science Conference Proceedings (OSTI)

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

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

2007-01-01T23:59:59.000Z

142

A multilevel voltage-source inverter with separate dc sources for static var generation  

SciTech Connect

A new multilevel voltage-source inverter with a separate dc sources is proposed for high-voltage, high-power applications, such as flexible ac transmission systems (FACTS) including static var generation (SVG), power line conditioning, series compensation, phase shifting, voltage balancing, fuel cell and photovoltaic utility systems interfacing, etc. The new M-level inverter consists of (M-1)/2 single phase full bridges in which each bridge has its own separate dc source. This inverter can generate almost sinusoidal waveform voltage with only one time switching per cycle as the number of levels increases. It can solve the problems of conventional transformer-based multipulse inverters and the problems of the multilevel diode-clamped inverter and the multilevel flying capacitor inverter. To demonstrate the superiority of the new inverter, a SVG system using the new inverter topology is discussed through analysis, simulation and experiment.

Peng, Fang Zheng [Tennessee Univ., Knoxville, TN (United States)]|[Oak Ridge National Lab., TN (United States); Lai, Jih-Sheng; McKeever, J.; VanCoevering, J. [Oak Ridge National Lab., TN (United States)

1995-09-01T23:59:59.000Z

143

Characterisation of the VELO High Voltage System  

E-Print Network (OSTI)

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

Barinjaka Rakotomiaramanana; Chris Parkes; Lars Eklund

2008-01-01T23:59:59.000Z

144

Perfect NOT transformation and conjugate transformation  

E-Print Network (OSTI)

The perfect NOT transformation, probabilistic perfect NOT transformation and conjugate transformation are studied. Perfect NOT transformation criteria on a quantum state set $S$ of a qubit are obtained. Two necessary and sufficient conditions for realizing a perfect NOT transformation on $S$ are derived. When these conditions are not satisfied we discuss a probabilistic perfect NOT transformation (gate). We construct a probabilistic perfect NOT machine (gate) by a general unitary-reduction operation. With a postselection of the measurement outcomes, the probabilistic NOT gate yields perfectly complements of the input states. We prove that one can realize probabilistically the NOT gate of the input states secretly chosen from a certain set $S=\\{|\\Psi_1>, |\\Psi_2>,..., |\\Psi_n>\\}$ if and only if $|\\Psi_1>, |\\Psi_2>,...,$ and $|\\Psi_n>$ are linearly independent. We also generalize the probabilistic NOT transformation to the conjugate transformation in the multi-level quantum system. The lower bound of the best p...

Yan, Fengli; Yan, Zhichao

2012-01-01T23:59:59.000Z

145

Bi-directional power control system for voltage converter  

DOE Patents (OSTI)

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

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

1999-01-01T23:59:59.000Z

146

Bi-directional power control system for voltage converter  

DOE Patents (OSTI)

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

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

1999-05-11T23:59:59.000Z

147

The effect of DVR location for enhancing voltage sag  

Science Conference Proceedings (OSTI)

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

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

2010-03-01T23:59:59.000Z

148

The Role of Recovery Transformers in an Integrated HILF Event Strategy  

Science Conference Proceedings (OSTI)

High-voltage transformers are critical to the continued, reliable operation of power systems. More than 90% of consumed power passes through high-voltage transformers on its way to customers. These large devices, each weighing hundreds of tons, are potentially vulnerable to high-impact, low-frequency (HILF) events, such as natural disasters, geomagnetic disturbances, electromagnetic pulses, intentional electromagnetic interference, and coordinated attacks. This vulnerability is compounded by the ...

2012-11-30T23:59:59.000Z

149

Definition: Operating Voltage | Open Energy Information  

Open Energy Info (EERE)

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

150

Lowering Power using the Voltage Identification Bit  

E-Print Network (OSTI)

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

Ken Chapman; Jameel Hussein

2012-01-01T23:59:59.000Z

151

Emergency Diesel Generator Voltage Regulator Guidelines  

Science Conference Proceedings (OSTI)

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

2005-12-20T23:59:59.000Z

152

Characterisation of the VELO High Voltage System  

E-Print Network (OSTI)

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

Rakotomiaramanana, B; Eklund, L

2008-01-01T23:59:59.000Z

153

Characterisation of the VELO High Voltage System  

E-Print Network (OSTI)

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

Rakotomiaramanana, B; Eklund, L

2008-01-01T23:59:59.000Z

154

Enhancing Open Circuit Voltage by Combining Thermoelectric ...  

Science Conference Proceedings (OSTI)

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

155

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

DOE Green Energy (OSTI)

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

Wohlgemuth, J.

2013-05-01T23:59:59.000Z

156

Voltage Source Converter Technology for Offshore Grids.  

E-Print Network (OSTI)

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

Vormedal, Pål Kristian Myhrer

2010-01-01T23:59:59.000Z

157

Quantum Voltage System Development and Dissemination  

Science Conference Proceedings (OSTI)

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

2012-11-14T23:59:59.000Z

158

Transformations | Open Energy Information  

Open Energy Info (EERE)

Transformations Transformations Jump to: navigation, search Name Transformations Place Townsend, MA Website http://transformations-inc.com References Transformations[1] Information About Partnership with NREL Partnership with NREL Yes Partnership Type Test & Evaluation Partner Partnering Center within NREL Electricity Resources & Building Systems Integration LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! Transformations is a company located in Townsend, MA. References ↑ "Transformations" Retrieved from "http://en.openei.org/w/index.php?title=Transformations&oldid=381743" Categories: Clean Energy Organizations Companies Organizations What links here Related changes Special pages Printable version Permanent link Browse properties

159

Spacetime transformation acoustics  

E-Print Network (OSTI)

A recently proposed analogue transformation method has allowed the extension of transformation acoustics to general spacetime transformations. We analyze here in detail the differences between this new analogue transformation acoustics (ATA) method and the standard one (STA). We show explicitly that STA is not suitable for transformations that mix space and time. ATA takes as starting point the acoustic equation for the velocity potential, instead of that for the pressure as in STA. This velocity-potential equation by itself already allows for some transformations mixing space and time, but not all of them. We explicitly obtain the entire set of transformations that do not leave its form invariant. It is in these cases that ATA shows its true potential, allowing for building a transformation acoustics method that enables the full range of spacetime transformations. We provide an example of an important transformation which cannot be achieved with STA. Using this transformation, we design and simulate an acous...

García-Meca, C; Barceló, C; Jannes, G; Sánchez-Dehesa, J; Martínez, A

2013-01-01T23:59:59.000Z

160

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

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


161

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

E-Print Network (OSTI)

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

Bak-Jensen, Birgitte

162

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

Science Conference Proceedings (OSTI)

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

Naohiro Hasegawa; Teruhisa Kumano

2010-02-01T23:59:59.000Z

163

Voltage Stability Studies for Southern Company Services  

Science Conference Proceedings (OSTI)

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

1997-12-31T23:59:59.000Z

164

Voltage regulation in linear induction accelerators  

DOE Patents (OSTI)

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

Parsons, W.M.

1991-03-19T23:59:59.000Z

165

Voltage regulation in linear induction accelerators  

DOE Patents (OSTI)

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

Parsons, W.M.

1992-12-29T23:59:59.000Z

166

Evaluation of higher distribution and/or utilization voltages. Final report  

SciTech Connect

An electric energy distribution/utilization system cost analysis model is presented for exploring cost tradeoffs (capital investment, operation and maintenance and cost of losses) and optimizing system configuration. The model focuses on the treatment of residential and light commercial service areas with time-varying load characteristics, including customer load profile changes, per customer load growth and service area population growth. Applications of the model are discussed. These include providing insight on: the selection of primary and secondary voltages; conductor sizing; distribution transformer sizing, change out policies and copper-to-core-loss ratio; and limits on allowable voltage variation at the service entrance. Examples are provided to illustrate model capabilities.

1980-09-10T23:59:59.000Z

167

Learning Transformations From Video  

E-Print Network (OSTI)

on Natural Video . . . . . . . . . . . . . . . . .3 Learning Continuous Transformation from VideoProposed Video Coder

Wang, Ching Ming

2010-01-01T23:59:59.000Z

168

Generative model transformer  

Science Conference Proceedings (OSTI)

The Generative Model Transformer (GMT) project is an Open Source initiative to build a Model Driven Architecure™ tool that allows fully customisable Platform Independent Models, Platform Description Models, Texture Mappings, and Refinement Transformations. ... Keywords: QVT, domain-specific languages, generative model transformer (GMT), model driven architecture (MDA), model transformation, open source

Jorn Bettin; Ghica van Emde Boas

2003-10-01T23:59:59.000Z

169

Strategies for Voltage Control and Transient Stability Assessment  

SciTech Connect

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

Hiskens, Ian A.

2013-09-25T23:59:59.000Z

170

Electrokinetic effects in power transformers  

Science Conference Proceedings (OSTI)

The behavior of dielectric fluids used for the cooling and insulation of power system equipment is significantly influenced by motion enforced by the action of circulating pumps. Not only can charges generated by streaming electrification accumulate to distort the electric field in positions where dielectric integrity is prejudiced, but the dielectric strength of the fluid is also altered per se by the actions of the flow in a complex, but predictable manner. Three important electrokinetic effects in transformer oil subjected to forced circulation are experimentally investigated using laboratory model ducts. Careful breakdown measurements with sustained voltage on flowing fluids have been extended to pulse voltages with a view to establishing the nature of time dependencies. The use of Schlieren optics on the duct has also demonstrated that flow patterns are modified by the imposition of electric fields through electrohydrodynamic (EHD) effects. Present model studies invite speculation that not only streaming electrification but also forced circulation per se may prejudice dielectric structure in power system equipment and these effects need to be understood to permit informed design and safe operation. These models are discussed in this paper. 122 refs., 82 figs., 10 tabs.

Nelson, J.K.; Lee, M.J. (Rensselaer Polytechnic Inst., Troy, NY (USA). Dept. of Electric Power Engineering)

1990-06-01T23:59:59.000Z

171

NREL: Measurements and Characterization - Current Versus Voltage  

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

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

172

High Voltage Safety Act | Department of Energy  

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

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

173

Flexible method for monitoring fuel cell voltage  

DOE Patents (OSTI)

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

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

2002-01-01T23:59:59.000Z

174

Corona and Motor Voltage Interim Report  

SciTech Connect

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

Hsu, J.S.

2005-05-06T23:59:59.000Z

175

A green transformer  

Science Conference Proceedings (OSTI)

The use of a new transformer and transformer fluid by a rural electric cooperative is described in the article. Edisol TR Transformers, which require about half as much fluid, are being used to replace existing transformers from 10- to 50 kVA. The dielectric fluid used in the transformers biodegrades more rapidly and completely, and is non-bioaccumulating in aquatic species. Standardized tests show that five to six weeks is required for biodegradation. The thermal design increases the efficiency of heat removal and reduces thermal gradients in the winding; the transformer is 20% smaller and 25% lighter than conventional transformers.

Wagner, A.

1997-03-01T23:59:59.000Z

176

Power system failure analysis by using the discrete wavelet transform  

Science Conference Proceedings (OSTI)

Voltage variations are the most common power quality events that may result in corruption of different industrial processes. The electric power utility industry requires significant improvement in the quality of power provided to customers during faults ... Keywords: discrete wavelet transform, power system failure, wavelet entropy

Ismail Yilmazlar; Gulden Kokturk

2010-05-01T23:59:59.000Z

177

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

E-Print Network (OSTI)

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

Claudio A. Cañizares

1991-01-01T23:59:59.000Z

178

Simulation Research of Tap Change Control of Converter Transformers for HVDC Transmission System  

Science Conference Proceedings (OSTI)

High voltage direct current(HVDC) control system plays an important role for the safety of HVDC transmission system. Converter transformer tap changes control is core component of HVDC control system. Stability of HVDC transmission system operation is ... Keywords: HVDC, simulation, converter transformer, tap change control, steady process

Wang Ying; Ma Cong; Wei Wen-hui; Wang Qing-ping

2012-03-01T23:59:59.000Z

179

Performance of a voltage peak detection-based flickermeter  

Science Conference Proceedings (OSTI)

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

Jiri Drapela

2009-12-01T23:59:59.000Z

180

Voltage controlled spintronics device for logic applications.  

SciTech Connect

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

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

1999-09-03T23:59:59.000Z

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


181

Voltage controlled spintronic devices for logic applications  

SciTech Connect

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

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

2000-05-01T23:59:59.000Z

182

On discrete cosine transform  

E-Print Network (OSTI)

The discrete cosine transform (DCT), introduced by Ahmed, Natarajan and Rao, has been used in many applications of digital signal processing, data compression and information hiding. There are four types of the discrete cosine transform. In simulating the discrete cosine transform, we propose a generalized discrete cosine transform with three parameters, and prove its orthogonality for some new cases. A new type of discrete cosine transform is proposed and its orthogonality is proved. Finally, we propose a generalized discrete W transform with three parameters, and prove its orthogonality for some new cases.

Zhou, Jianqin

2011-01-01T23:59:59.000Z

183

Feasibility Study for the Development of High-Voltage, Low-Current Power Semiconductor Devices: 2003 Strategic Science and Technolog y Project  

Science Conference Proceedings (OSTI)

The intelligent universal transformer (IUT) will be an advanced power-electronics replacement for conventional distribution transformers that adds significant new functional capabilities to those available from conventional copper and iron transformers. This report assesses the state of the art and development options for obtaining high-voltage, low-current power semiconductors (both switches and diodes) needed in the circuit topology being developed for the IUT.

2004-03-29T23:59:59.000Z

184

Transformer current sensor for superconducting magnetic coils  

DOE Patents (OSTI)

A transformer current sensor having primary turns carrying a primary current for a superconducting coil and secondary turns only partially arranged within the primary turns. The secondary turns include an active winding disposed within the primary turns and a dummy winding which is not disposed in the primary turns and so does not experience a magnetic field due to a flow of current in the primary turns. The active and dummy windings are wound in opposite directions or connected in series-bucking relationship, and are exposed to the same ambient magnetic field. Voltages which might otherwise develop in the active and dummy windings due to ambient magnetic fields thus cancel out. The resultant voltage is purely indicative of the rate of change of current flowing in the primary turns.

Shen, Stewart S. (Oak Ridge, TN); Wilson, C. Thomas (Norris, TN)

1988-01-01T23:59:59.000Z

185

System for increasing corona inception voltage of insulating oils  

DOE Patents (OSTI)

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

Rohwein, Gerald J. (Albuquerque, NM)

1998-01-01T23:59:59.000Z

186

Low voltage arc formation in railguns  

DOE Patents (OSTI)

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

Hawke, R.S.

1985-08-05T23:59:59.000Z

187

Low voltage arc formation in railguns  

DOE Patents (OSTI)

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

Hawke, Ronald S. (Livermore, CA)

1987-01-01T23:59:59.000Z

188

Low voltage arc formation in railguns  

DOE Patents (OSTI)

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

Hawke, R.S.

1987-11-17T23:59:59.000Z

189

High-voltage-compatible, fully depleted CCDs  

SciTech Connect

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

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

2006-05-15T23:59:59.000Z

190

Property:Nominal Voltage | Open Energy Information  

Open Energy Info (EERE)

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

191

Assessment of Voltage Security Methods and Tools  

Science Conference Proceedings (OSTI)

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

1995-10-26T23:59:59.000Z

192

Superconducting Low Voltage Direct Current (LVDC) Networks  

Science Conference Proceedings (OSTI)

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

1994-04-27T23:59:59.000Z

193

Spark gap with low breakdown voltage jitter  

SciTech Connect

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

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

1996-01-01T23:59:59.000Z

194

Voltage Control Optimization to Improve Transmission Efficiency  

Science Conference Proceedings (OSTI)

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

2012-11-08T23:59:59.000Z

195

Metrics for enterprise transformation  

E-Print Network (OSTI)

The objective of this thesis is to depict the role of metrics in the evolving journey of enterprise transformation. To this end, three propositions are explored: (i) metrics and measurement systems drive transformation, ...

Blackburn, Craig D. (Craig David), S. M. Massachusetts Institute of Technology

2009-01-01T23:59:59.000Z

196

Modular high voltage power supply for chemical analysis  

DOE Patents (OSTI)

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

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

2007-01-09T23:59:59.000Z

197

Modular high voltage power supply for chemical analysis  

DOE Patents (OSTI)

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

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

2008-07-15T23:59:59.000Z

198

Understanding and Mitigating Corrosive Sulfur Risks in Oil-Filled Transformers  

Science Conference Proceedings (OSTI)

In recent years, there have been an increasing number of documented cases of transformer failures attributed to corrosive sulfur in oil. Reports to date include failures in generator step-up (GSU) transformers, high-voltage direct current (HVDC) transformers, and shunt reactors from various designs and manufacturers with different oil sources. Most utilities see this as a serious concern because failures have occurred without prior warning and failures can not be predicted by traditional tests (for examp...

2011-03-24T23:59:59.000Z

199

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

SciTech Connect

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

None

2012-01-25T23:59:59.000Z

200

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

Science Conference Proceedings (OSTI)

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

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


201

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

Science Conference Proceedings (OSTI)

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

202

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

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

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

203

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

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

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

204

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

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

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

205

Green Island Power Authority Transmission Voltage Support System...  

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

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

206

Typechecking for XML transformers  

Science Conference Proceedings (OSTI)

We study the typechecking problem for XML transformers: given an XML transformation program and a DTD for the input XML documents, check whether every result of the program conforms to a specified output DTD. We model XML transformers using a novel device ...

Tova Milo; Dan Suciu; Victor Vianu

2000-05-01T23:59:59.000Z

207

A dc transformer  

Science Conference Proceedings (OSTI)

Although conventional transformers are ac, a device that may be termed a dc transformer has been constructed by using superconductors. To provide an understanding of how such a transformer would operate, some of the properties of type I and type II superconductors ...

I. Giaever

1966-09-01T23:59:59.000Z

208

Research on Fault Diagnosis on High Voltage SF6 Circuit Breaker Based on the Db Wavelet and Fuzzy Theory  

Science Conference Proceedings (OSTI)

This dissertation aims at providing a quick and accurate fault diagnosis method for on high voltage SF6circuit breaker. This method indirectly monitors the functioning of the breaker by observing the electric current in the coil of its switch. The electrical ... Keywords: SF6 circuit breaker, monitor, wavelet transform, fuzzy theory

Li Yang; Zhuo Yang; Yang Lei; Kejie Dai; Weiming Guan

2012-05-01T23:59:59.000Z

209

A Value Proposition for Developing an Industry Database for High Voltage Circuit Breakers & CIM Data Objects for T&D  

Science Conference Proceedings (OSTI)

EPRI initiated work to develop databases for performance analysis and benchmarking in order to address issues of performance data availability, support industry efforts to maximize power delivery asset values, and optimize maintenance activities. With the successful development of an industrywide database for distribution cables and the extension of that work to power transformers, interest has turned to high-voltage circuit breakers (HVCBs).

2007-11-19T23:59:59.000Z

210

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

Science Conference Proceedings (OSTI)

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

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

2008-01-01T23:59:59.000Z

211

Transforming a Transformative School | Department of Energy  

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

You are here You are here Home » Transforming a Transformative School Transforming a Transformative School October 11, 2012 - 10:14am Addthis During a yearlong renovation, Harding Charter Preparatory school upgraded lighting fixtures, installed a new heating and cooling system, and replaced the entry doors. The new doors allow daylight into the school and restore the historical building envelope. | Photo courtesy of John Winkel, Energy Department. During a yearlong renovation, Harding Charter Preparatory school upgraded lighting fixtures, installed a new heating and cooling system, and replaced the entry doors. The new doors allow daylight into the school and restore the historical building envelope. | Photo courtesy of John Winkel, Energy Department. Julie McAlpin

212

High voltage power supply with modular series resonant inverters  

DOE Patents (OSTI)

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

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

1995-01-01T23:59:59.000Z

213

High voltage power supply with modular series resonant inverters  

DOE Patents (OSTI)

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

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

1995-07-18T23:59:59.000Z

214

A Superconducting transformer system for high current cable testing  

Science Conference Proceedings (OSTI)

This article describes the development of a direct-current (dc) superconducting transformer system for the high current test of superconducting cables. The transformer consists of a core-free 10 464 turn primary solenoid which is enclosed by a 6.5 turn secondary. The transformer is designed to deliver a 50 kA dc secondary current at a dc primary current of about 50 A. The secondary current is measured inductively using two toroidal-wound Rogowski coils. The Rogowski coil signal is digitally integrated, resulting in a voltage signal that is proportional to the secondary current. This voltage signal is used to control the secondary current using a feedback loop which automatically compensates for resistive losses in the splices to the superconducting cable samples that are connected to the secondary. The system has been commissioned up to 28 kA secondary current. The reproducibility in the secondary current measurement is better than 0.05% for the relevant current range up to 25 kA. The drift in the secondary current, which results from drift in the digital integrator, is estimated to be below 0.5 A/min. The system's performance is further demonstrated through a voltage-current measurement on a superconducting cable sample at 11 T background magnetic field. The superconducting transformer system enables fast, high resolution, economic, and safe tests of the critical current of superconducting cable samples.

Godeke, A.; Dietderich, D. R.; Joseph, J. M.; Lizarazo, J.; Prestemon, S. O.; Miller, G.; Weijers, H. W.

2010-02-15T23:59:59.000Z

215

Motor voltage high harmonics influence to efficient energy usage  

Science Conference Proceedings (OSTI)

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

Miloje M. Kostic; Branka B. Kostic

2011-07-01T23:59:59.000Z

216

Distribution System Voltage Performance Analysis for High-Penetration Photovoltaics  

DOE Green Energy (OSTI)

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

Liu, E.; Bebic, J.

2008-02-01T23:59:59.000Z

217

Optimal Compensation Algorithms for a Dynamic Voltage Restorer  

Science Conference Proceedings (OSTI)

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

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

2010-06-01T23:59:59.000Z

218

Analysis of Voltage Rise Effect on Distribution Network with Distributed  

E-Print Network (OSTI)

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

Pota, Himanshu Roy

219

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

E-Print Network (OSTI)

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

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

2005-01-01T23:59:59.000Z

220

Electronic circuit for measuring series connected electrochemical cell voltages  

DOE Patents (OSTI)

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

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

2000-01-01T23:59:59.000Z

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


221

The interlaced chirp Z transform  

Science Conference Proceedings (OSTI)

In this paper we introduce the interlaced chirp Z transform (Interlaced CZT), It is based on the computation of several carefully staggered CZT that are progressively interlaced to result in a spectrum that has denser frequency samples where needed. ... Keywords: chirp Z transform, discrete fourier transform, interlaced chirp Z transform, warped discrete fourier transform, zoom chirp Z transform

Indranil Sarkar; Adly T. Fam

2006-09-01T23:59:59.000Z

222

Developments in line-voltage thermostats  

Science Conference Proceedings (OSTI)

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

Kesselring, J.

1992-09-01T23:59:59.000Z

223

Transforming Commercial Building Operations  

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

Transforming Commercial Building Operations Transforming Commercial Building Operations Transforming Commercial Building Operations Ron Underhill Pacific Northwest National Laboratory ronald.underhill@pnnl.gov (509)375-9765 April 4, 2013 2 | Building Technologies Office eere.energy.gov * Most buildings are not commissioned (Cx) before occupancy, including HVAC and lighting systems * Buildings often are poorly operated and maintained leading to significant energy waste of 5 to 20%, even when they have building automation systems (BASs)

224

Transforming Commercial Building Operations  

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

Transforming Commercial Building Operations Transforming Commercial Building Operations Transforming Commercial Building Operations Ron Underhill Pacific Northwest National Laboratory ronald.underhill@pnnl.gov (509)375-9765 April 4, 2013 2 | Building Technologies Office eere.energy.gov * Most buildings are not commissioned (Cx) before occupancy, including HVAC and lighting systems * Buildings often are poorly operated and maintained leading to significant energy waste of 5 to 20%, even when they have building automation systems (BASs)

225

Adaptive Discrete Cosine Transform  

Science Conference Proceedings (OSTI)

The theory and performance of the adaptive discrete cosine transform filter is examined. The discrete cosine transform filter is a realization of an FIR filter as the cascade of an all-zero FIR filter with a bank of IIR digital resonators. Each bank ... Keywords: FIR filter, IIR digital resonators, LMS algorithm, adaptive discrete cosine transform filter, adaptive filters, all-zero FIR filter, filter coefficient, frequency, magnitude, phase, transfer function, update method

S. J. Bukowinski; L. Gerhardt; M. Fargues; G. Coutu

1995-10-01T23:59:59.000Z

226

EPRI Transformer Guidebook Development  

Science Conference Proceedings (OSTI)

Utilities are losing many of their subject matter experts through retirement and downsizing. This is particularly true in the case of power transformers, so that there is now a critical need for a comprehensive transformer reference book geared toward utility engineers. In 2007, the Electric Power Research Institute EPRI published the technical update report Transformer Guidebook Design 1013799. That report described the results of the initial project to develop the Copper Book, a comprehensive reference...

2009-12-23T23:59:59.000Z

227

A New Integral Transform  

E-Print Network (OSTI)

Using Bauer's expansion and properties of spherical Bessel and Legender functions, we deduce a new transform and briefly indicate its use.

B. G. Sidharth

2004-12-04T23:59:59.000Z

228

Transforming the Freight Industry  

E-Print Network (OSTI)

Transforming the Freight Industry From Regulation to Icommon-carrier freight industry was Competition to backwardjourneys. When the freight industry was deregulated, it was

Regan, Amelia

2002-01-01T23:59:59.000Z

229

Transformer Ratio Enhancement Experiment  

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

TRANSFORMER RATIO ENHANCEMENT EXPERIMENT A. Kanareykin, Euclid Concepts LLC, Solon, OH 44139, USA W. Gai, J. G. Power. ANL, Argonne, IL, 60439, USA E. Nenasheva, Ceramics Ltd., St....

230

Market Transformation Programs  

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

Efficiency Improvement Opportunities in TVs Implications for Market Transformation Programs journal Energy Policy volume year month pages keywords appliance energy efficiency...

231

Group 3: Humidity, Temperature and Voltage (Presentation)  

SciTech Connect

This is a summary of the work of Group 3 of the International PV QA Task Force. Group 3 is chartered to develop accelerated stress tests that can be used as comparative predictors of module lifetime versus stresses associated with humidity, temperature and voltage.

Wohlgemuth, J.

2013-09-01T23:59:59.000Z

232

High voltage VLF testing of power cables  

SciTech Connect

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

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

1997-04-01T23:59:59.000Z

233

Transformer requirements for the year 2000. Final report, December 1979  

Science Conference Proceedings (OSTI)

The principal objective of this program was to determine the design parameters required for transformers of the year 2000. The approach to meeting this objective was to determine the changes which may occur in transmission and distribution systems over the next twenty years, and how these changes might affect design parameters of distribution and power transformers. Emphasis was placed on domestic requirements, although the impact of international practices was factored into the overall requirements for transformers. Possible investigations that could help transformer designers meet the long term technical requirements of future transformers were also identified. The principal conclusions of this study were: 1200 kV transmission could be in service by the late 1980's and it is essential to develop 1200 kV transformers for these systems; transformer manufacturers must be prepared to supply higher MVA ratings at all voltage levels; there will be a strong demand for low-loss, minimum cost transformers; and environmental/safety, reliability, and size reduction considerations will increase in importance. (LLL)

Not Available

1980-06-01T23:59:59.000Z

234

Influence of instrument transformers on power system protection  

E-Print Network (OSTI)

Instrument transformers are a crucial component of power system protection. They supply the protection system with scaled-down replicas of current and voltage signals present in a power network to the levels which are safe and practical to op- erate with. The conventional instrument transformers are based on electromagnetic coupling between the power network on the primary side and protective devices on the secondary. Due to such a design, instrument transformers insert distortions in the mentioned signal replicas. Protective devices may be sensitive to these distortions. The inuence of distortions may lead to disastrous misoperations of protective devices. To overcome this problem, a new instrument transformer design has been devised: optical sensing of currents and voltages. In the theory, novel instrument transform- ers promise a distortion-free replication of the primary signals. Since the mentioned novel design has not been widely used in practice so far, its superior performance needs to be evaluated. This poses a question: how can the new technology (design) be evaluated, and compared to the existing instrument transformer technology? The importance of this question lies in its consequence: is there a necessity to upgrade the protection system, i.e. to replace the conventional instrument transformers with the novel ones, which would be quite expensive and time-consuming? The posed question can be answered by comparing inuences of both the novel and the conventional instrument transformers on the protection system. At present, there is no systematic approach to this evaluation. Since the evaluation could lead to an improvement of the overall protection system, this thesis proposes a comprehensive and systematic methodology for the evaluation. The thesis also proposes a complete solution for the evaluation, in the form of a simulation environment. Finally, the thesis presents results of evaluation, along with their interpretation.

Naodovic, Bogdan

2005-05-01T23:59:59.000Z

235

Transformations of Grassman Spaces  

E-Print Network (OSTI)

This is a version of a part of the book ``Transformations of Grassman Spaces'' (in progress). We study transformations of Grassman spaces preserving certain geometrical constructions related to buildings. The next part will be devoted to Grassman spaces associated with polar spaces.

Mark Pankov

2004-04-05T23:59:59.000Z

236

Deployment & Market Transformation (Brochure)  

SciTech Connect

NREL's deployment and market transformation (D and MT) activities encompass the laboratory's full range of technologies, which span the energy efficiency and renewable energy spectrum. NREL staff educates partners on how they can advance sustainable energy applications and also provides clients with best practices for reducing barriers to innovation and market transformation.

Not Available

2012-04-01T23:59:59.000Z

237

Generalized Lorentz Transformations  

E-Print Network (OSTI)

Generalized Lorentz transformations with modified velocity parameter are considered. Lorentz transformations depending on the mass of the observer are suggested.The modified formula for the addition of velocities remarkably preserves the constancy of the velocity of light for all observers. The Doppler red shift is affected and can provide a test of such generalisations.

Virendra Gupta

2013-05-22T23:59:59.000Z

238

Biochemical transformation of coals  

DOE Patents (OSTI)

A method of biochemically transforming macromolecular compounds found in solid carbonaceous materials, such as coal is provided. The preparation of new microorganisms, metabolically weaned through challenge growth processes to biochemically transform solid carbonaceous materials at extreme temperatures, pressures, pH, salt and toxic metal concentrations is also disclosed. 7 figs.

Lin, M.S.; Premuzic, E.T.

1999-03-23T23:59:59.000Z

239

Deployment & Market Transformation (Brochure)  

SciTech Connect

NREL's deployment and market transformation (D and MT) activities encompass the laboratory's full range of technologies, which span the energy efficiency and renewable energy spectrum. NREL staff educates partners on how they can advance sustainable energy applications and also provides clients with best practices for reducing barriers to innovation and market transformation.

2012-04-01T23:59:59.000Z

240

The analysis of an ungrounded Wye-Delta transformer bank serving an induction motor and single-phase lighting loads  

SciTech Connect

This paper documents the detailed analysis of the three-phase ungrounded wye-delta transformer bank serving a combination three-phase induction motor and single-phase lighting load. A 3 x 3 transfer function matrix is developed that makes it possible to determine the load line-to-line voltages with a knowledge of the primary voltages of the transformer bank. Included in the transfer function matrix are the transformer impedances, unsymmetrical secondary impedance matrix, and the impedances of the motor and single-phase lighting load.

Kersting, W.H.; Rathbun, J.S.

2000-02-01T23:59:59.000Z

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


241

Surge Protection in Low-Voltage AC Power Circuits – An ...  

Science Conference Proceedings (OSTI)

... Discusses low side surges and effects on distribution transformers. Discusses effect of secondary arresters on distribution transformer failures. ...

2013-05-20T23:59:59.000Z

242

A discrete fractional random transform  

E-Print Network (OSTI)

We propose a discrete fractional random transform based on a generalization of the discrete fractional Fourier transform with an intrinsic randomness. Such discrete fractional random transform inheres excellent mathematical properties of the fractional Fourier transform along with some fantastic features of its own. As a primary application, the discrete fractional random transform has been used for image encryption and decryption.

Zhengjun Liu; Haifa Zhao; Shutian Liu

2006-05-20T23:59:59.000Z

243

Lorentz transformation by mimicking the Lorentz transformation  

E-Print Network (OSTI)

We show that starting with the fact that special relativity theory is concerned with a distortion of the observed length of a moving rod, without mentioning if it is a "contraction" or "dilation", we can derive the Lorentz transformations for the spacetime coordinates of the same event. This derivation is based on expressing the length of the moving rod as a sum of components with all the lengths involved in this summation being measured by the observers of the same inertial reference frame.

Bernhard Rothenstein; Stefan Popescu

2007-07-16T23:59:59.000Z

244

Electrical system architecture having high voltage bus  

DOE Patents (OSTI)

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

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

2011-03-22T23:59:59.000Z

245

Sacramento Area Voltage Support Environmental Impact Statement  

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

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

246

LOW VOLTAGE 14 Mev NEUTRON SOURCE  

DOE Patents (OSTI)

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

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

1959-09-29T23:59:59.000Z

247

Low Swing Dual Threshold Voltage Domino Logic  

E-Print Network (OSTI)

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

Volkan Kursun; Eby G. Friedman

2002-01-01T23:59:59.000Z

248

Market Transformation Fact Sheet  

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

Transformation Market Transformation is based on the concept that federal support can catalyze a market to achieve economic and environmental benefits that can reduce costs through economies of scale. Adoption of fuel cells in emerging markets expands the growth of green jobs, with new opportunities in manufacturing, fuel cell maintenance and support systems, and domestic hydrogen fuel production and delivery. By providing reliable field operations data and increasing user confidence, early market deployments help overcome non-technical challenges like developing appropriate safety codes and standards and reducing high insurance costs. Strategies Market Transformation's primary goal is to accelerate the expansion of hydrogen and fuel cell use by lowering the life

249

HIGH VOLTAGE, HIGH CURRENT SPARK GAP SWITCH  

DOE Patents (OSTI)

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

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

1962-04-17T23:59:59.000Z

250

Low-Voltage Cable Aging Management Guidance  

Science Conference Proceedings (OSTI)

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

2013-12-23T23:59:59.000Z

251

A compact high voltage pulse generator  

SciTech Connect

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

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

1994-07-01T23:59:59.000Z

252

A high voltage pulsed power supply for capillary discharge waveguide applications  

Science Conference Proceedings (OSTI)

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

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

2011-06-15T23:59:59.000Z

253

Electro-optic voltage sensor head  

DOE Patents (OSTI)

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

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

1999-01-01T23:59:59.000Z

254

Electro-optic voltage sensor head  

DOE Patents (OSTI)

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

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

1999-08-17T23:59:59.000Z

255

Assessing Power Quality Levels from a Limited Set of Monitoring Data: Methodology and Proof of Concept for Sag Transformation Modeli ng  

Science Conference Proceedings (OSTI)

With the increased sensitivity of power electronic and digital automation systems to momentary interruptions, voltage sags, transients, and harmonics, characterization of power quality levels has become extremely important. This report describes the proof-of-concept for a voltage sag transformation method and its verification based on field data and simulations using the Electromagnetic Transients Program (TM) (EMTP (TM)).

2001-11-08T23:59:59.000Z

256

Physical design with multiple on-chip voltages  

Science Conference Proceedings (OSTI)

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

Chunhong Chen

2002-04-01T23:59:59.000Z

257

Transformation inverse design  

E-Print Network (OSTI)

We present a new technique for the design of transformation-optics devices based on large-scale optimization to achieve the optimal effective isotropic dielectric materials within prescribed index bounds, which is ...

Liu, David

258

The Quantum Mellin transform  

E-Print Network (OSTI)

We uncover a new type of unitary operation for quantum mechanics on the half-line which yields a transformation to ``Hyperbolic phase space''. We show that this new unitary change of basis from the position x on the half line to the Hyperbolic momentum $p_\\eta$, transforms the wavefunction via a Mellin transform on to the critial line $s=1/2-ip_\\eta$. We utilise this new transform to find quantum wavefunctions whose Hyperbolic momentum representation approximate a class of higher transcendental functions, and in particular, approximate the Riemann Zeta function. We finally give possible physical realisations to perform an indirect measurement of the Hyperbolic momentum of a quantum system on the half-line.

J. Twamley; G. J. Milburn

2007-02-12T23:59:59.000Z

259

On Bianchi's Backlund transformation  

E-Print Network (OSTI)

We investigate basic features of Bianchi's B\\"acklund transformation of quadrics to see if it can be obtained under weaker assumptions and if it can be generalized to deformations of other surfaces.

Dinca, Ion

2011-01-01T23:59:59.000Z

260

Imaging Fourier transform spectrometer  

DOE Patents (OSTI)

This invention is comprised of an imaging Fourier transform spectrometer having a Fourier transform infrared spectrometer providing a series of images to a focal plane array camera. The focal plane array camera is clocked to a multiple of zero crossing occurrences as caused by a moving mirror of the Fourier transform infrared spectrometer and as detected by a laser detector such that the frame capture rate of the focal plane array camera corresponds to a multiple of the zero crossing rate of the Fourier transform infrared spectrometer. The images are transmitted to a computer for processing such that representations of the images as viewed in the light of an arbitrary spectral ``fingerprint`` pattern can be displayed on a monitor or otherwise stored and manipulated by the computer.

Bennett, C.L.

1993-09-13T23:59:59.000Z

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


261

Series Transmission Line Transformer  

DOE Patents (OSTI)

A series transmission line transformer is set forth which includes two or more of impedance matched sets of at least two transmissions lines such as shielded cables, connected in parallel at one end ans series at the other in a cascading fashion. The cables are wound about a magnetic core. The series transmission line transformer (STLT) which can provide for higher impedance ratios and bandwidths, which is scalable, and which is of simpler design and construction.

Buckles, Robert A. (Livermore, CA); Booth, Rex (Livermore, CA); Yen, Boris T. (El Cerrito, CA)

2004-06-29T23:59:59.000Z

262

NIST Online Museum of Quantum Voltage Standards, 1990s  

Science Conference Proceedings (OSTI)

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

2013-02-28T23:59:59.000Z

263

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

Science Conference Proceedings (OSTI)

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

264

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

Science Conference Proceedings (OSTI)

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

265

Temperature Fitting Method Predicting Equidistant Voltage Drop of ...  

Science Conference Proceedings (OSTI)

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

266

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

Science Conference Proceedings (OSTI)

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

1998-12-31T23:59:59.000Z

267

Transforming the Market for Commercial and Industrial Distribution Transformers: A Government, Manufacturer, and Utility Collaboration  

E-Print Network (OSTI)

Distribution transformers offer a largely untapped opportunity for efficiency improvements in buildings. Application of energy-efficient equipment can reduce transformer losses by about 20%, substantially cutting a facility’s total electricity bill and offering typical paybacks less than three years. Since nearly all of the electricity powering the commercial and industrial sectors is stepped down in voltage by facility-owned distribution transformers, broad application of energy-efficient equipment will lead to huge economy-wide energy and dollar savings as well as associated environmental benefits. This opportunity has led to a multi-party coordinated effort that offers a new model for national partnerships to pursue market transformation. The model, called the Informal Collaborative Model for the purposes of this paper, is characterized by voluntary commitments of multiple stakeholders to carry out key market interventions in a coordinated fashion, but without pooling resources or control. Collaborative participants are joined by a common interest in establishing and expanding the market for a new product, service, or practice that will yield substantial energy savings. This paper summarizes the technical efficiency opportunity available in distribution

Andrew Delaski; Consortium For Energy Efficiency

1998-01-01T23:59:59.000Z

268

System for increasing corona inception voltage of insulating oils  

DOE Patents (OSTI)

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

Rohwein, G.J.

1998-05-19T23:59:59.000Z

269

Research of Dynamic Voltage Restorer Based on Repetitive Control Strategy  

Science Conference Proceedings (OSTI)

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

Tianyu Liu

2012-10-01T23:59:59.000Z

270

Distributed Generation Source Stiffness and Its Impact on Voltage Distortion  

Science Conference Proceedings (OSTI)

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

2001-11-27T23:59:59.000Z

271

Selective compensation of voltage harmonics in grid-connected microgrids  

E-Print Network (OSTI)

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

Vasquez, Juan Carlos

272

Secondary Control for Voltage Unbalance Compensation in an Islanded Microgrid  

E-Print Network (OSTI)

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

Vasquez, Juan Carlos

273

Optical transformation from chirplet to fractional Fourier transformation kernel  

E-Print Network (OSTI)

We find a new integration transformation which can convert a chirplet function to fractional Fourier transformation kernel, this new transformation is invertible and obeys Parseval theorem. Under this transformation a new relationship between a phase space function and its Weyl-Wigner quantum correspondence operator is revealed.

Hong-yi Fan; Li-yun Hu

2009-02-11T23:59:59.000Z

274

Optical transformation from chirplet to fractional Fourier transformation kernel  

E-Print Network (OSTI)

We find a new integration transformation which can convert a chirplet function to fractional Fourier transformation kernel, this new transformation is invertible and obeys Parseval theorem. Under this transformation a new relationship between a phase space function and its Weyl-Wigner quantum correspondence operator is revealed.

Fan, Hong-yi

2009-01-01T23:59:59.000Z

275

Capacitively coupled RF voltage probe having optimized flux linkage  

DOE Patents (OSTI)

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

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

1999-02-02T23:59:59.000Z

276

Transformer coupling for transmitting direct current through a barrier  

DOE Patents (OSTI)

The transmission system for transmitting direct current from an energy source on one side of an electrical and mechanical barrier to a load on the other side of the barrier utilizes a transformer comprising a primary core on one side of the transformer and a secondary core on the other side of the transformer. The cores are magnetically coupled selectively by moving a magnetic ferrite coupler in and out of alignment with the poles of the cores. The direct current from the energy source is converted to a time varying current by an oscillating circuit, which oscillating circuit is optically coupled to a secondary winding on the secondary core to interrupt oscillations upon the voltage in the secondary winding exceeding a preselected level.

Brown, Ralph L. (Albuquerque, NM); Guilford, Richard P. (Albuquerque, NM); Stichman, John H. (Albuquerque, NM)

1988-01-01T23:59:59.000Z

277

Transformer coupling for transmitting direct current through a barrier  

DOE Patents (OSTI)

The transmission system for transmitting direct current from an energy source on one side of an electrical and mechanical barrier to a load on the other side of the barrier utilizes a transformer comprising a primary core on one side of the transformer and a secondary core on the other side of the transformer. The cores are magnetically coupled selectively by moving a magnetic ferrite coupler in and out of alignment with the poles of the cores. The direct current from the energy source is converted to a time varying current by an oscillating circuit, which oscillating circuit is optically coupled to a secondary winding on the secondary core to interrupt oscillations upon the voltage in the secondary winding exceeding a preselected level. 4 figs.

Brown, R.L.; Guilford, R.P.; Stichman, J.H.

1987-06-29T23:59:59.000Z

278

Contact transformations for difference schemes  

E-Print Network (OSTI)

We define a class of transformations of the dependent and independent variables in an ordinary difference scheme. The transformations leave the solution set of the system invariant and reduces to a group of contact transformations in the continuous limit. We use a simple example to show that the class is not empty and that such "contact transformations for discrete systems" genuinely exist.

Levi, Decio; Winternitz, Pavel

2011-01-01T23:59:59.000Z

279

Reactive Power Measurement Using the Wavelet Transform  

E-Print Network (OSTI)

Abstract—This paper provides the theoretical basis for the measurement of reactive and distortion powers from the wavelet transforms. The measurement of reactive power relies on the use of broad-band phase-shift networks to create concurrent in-phase currents and quadrature voltages. The wavelet real power computation resulting from these 90 phase-shift networks yields the reactive power associated with each wavelet frequency level or subband. The distortion power at each wavelet subband is then derived from the real, reactive and apparent powers of the subband, where the apparent power is the product of the v; i element pair's subband rms voltage and current. The advantage of viewing the real and reactive powers in the wavelet domain is that the domain preserves both the frequency and time relationship of these powers. In addition, the reactive power associated with each wavelet subband is a signed quantity and thus has a direction associated with it. This permits tracking the reactive power flow in each subband through the power system. Index Terms—Digital signal processing, phase shift networks, measurement, power, RMS, subband, wavelets. I.

Weon-ki Yoon; Michael J. Devaney

2000-01-01T23:59:59.000Z

280

Low voltage operation of plasma focus  

SciTech Connect

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

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

2010-08-15T23:59:59.000Z

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


281

High Voltage GaN Schottky Rectifiers  

SciTech Connect

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

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

1999-10-25T23:59:59.000Z

282

Functional Mellin Transforms  

E-Print Network (OSTI)

Functional integrals are defined in terms of locally compact topological groups and their associated Banach-valued Haar integrals. This approach generalizes the functional integral scheme of Cartier and DeWitt-Morette. The definition allows a construction of functional Mellin transforms. In turn, the functional Mellin transforms can be used to define functional traces, logarithms, and determinants. The associated functional integrals are useful tools for probing function spaces in general and $C^\\ast$-algebras in particular. Several interesting aspects are explored. As an application, we construct a functional Mellin representation of the quantum evolution operator.

J. LaChapelle

2013-08-05T23:59:59.000Z

283

Model Transformations And Tool Integration  

E-Print Network (OSTI)

Model transformations are increasingly recognised as being of significant importance to many areas of software development and integration. Recent attention on model transformations has particularly focused on the OMG's Queries / Views / Transformations (QVT) Request for Proposals (RFP). In this paper I motivate the need for dedicated approaches to model transformations, particularly for the data involved in tool integration, outline the challenges involved, and then present a number of technologies and techniques which allow the construction of flexible, powerful and practical model transformations.

Laurence Tratt

2004-01-01T23:59:59.000Z

284

Coordinate transformations in quaternion spaces  

E-Print Network (OSTI)

The quaternion spaces can be used to describe the property of electromagnetic field and gravitational field. In the quaternion space, some coordinate transformations can be deduced from the feature of quaternions, including Lorentz transformation and Galilean transformation etc., when the coordinate system is transformed into others. And some coordinate transformations with variable speed of light can be obtained in the electromagnetic field and gravitational field.

Zihua Weng

2008-08-31T23:59:59.000Z

285

CRYOGENIC LIFETIME TESTS ON A COMMERCIAL EPOXY RESIN HIGH VOLTAGE BUSHING  

SciTech Connect

High-temperature superconducting (HTS) power devices operating in liquid nitrogen frequently require high-voltage bushings to carry the current leads from the superconducting windings to the room temperature grid connections. Oak Ridge National Laboratory is collaborating with Waukesha Electric Systems, SuperPower, and Southern California Edison to develop and demonstrate an HTS utility power transformer. Previous dielectric high voltage tests in support of this program have been carried out in test cryostats with commercial epoxy resin bushings from Electro Composites Inc. (ECI). Though the bushings performed well in these short-term tests, their long-term operation at high voltage in liquid nitrogen needs to be verified for use on the utility grid. Long-term tests are being carried out on a sample 28-kV-class ECI bushing. The bushing has a monolithic cast, cycloaliphatic resin body and is fire- and shatter-resistant. The test cryostat is located in an interlocked cage and is energized at 25 kVac around the clock. Liquid nitrogen (LN) is automatically refilled every 9.5 hours. Partial discharge, capacitance, and leakage resistance tests are periodically performed to check for deviations from factory values. At present, over 2400 hours have been accumulated with no changes in these parameters. The tests are scheduled to run for four to six months.

Schwenterly, S W [ORNL; Pleva, Ed [Waukesha Electric Systems, Waukesha, WI; Ha, Tam T [ORNL

2012-01-01T23:59:59.000Z

286

Minimum Energy Compensation Strategy and Characteristic Analysis for Dynamic Voltage Restorer  

Science Conference Proceedings (OSTI)

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

Yingying Liu; Xu Yonghai; Xiao Xiangning; Guo Chunlin

2009-10-01T23:59:59.000Z

287

Research on the SPLL based single phase voltage sag detection technique  

Science Conference Proceedings (OSTI)

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

Xie Yue; Chen Le; Sun Jian; Gong Xu

2008-04-01T23:59:59.000Z

288

Algorithms for transform selection in multiple-transform video compression  

E-Print Network (OSTI)

Selecting proper transforms for video compression has been based on the rate-distortion criterion. Transforms that appear reasonable are incorporated into a video coding system and their performance is evaluated. This ...

Cai, Xun, S.M. Massachusetts Institute of Technology

2012-01-01T23:59:59.000Z

289

Sequential circuit design for radiation hardened multiple voltage integrated circuits  

DOE Patents (OSTI)

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

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

2009-11-24T23:59:59.000Z

290

Waveform Characteristics of Voltage Sags: Definition and Algorithm Development  

Science Conference Proceedings (OSTI)

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

1999-08-05T23:59:59.000Z

291

Analysis of leakage magnetic problems in shell-form power transformer  

Science Conference Proceedings (OSTI)

The principles of minimized magnetic energy and voltage equilibrium have been combined with the finite element method to solve the leakage magnetic field problems coupled with an unknown ampere-turn distribution in the shell-form power transformer. Based on the leakage magnetic field calculated, the eddy current and circulating current losses in the coils are further computed. The calculated results are consistent with measured values for a model of a shell-form transformer. Above principles are applied to the windings design of a 50MVA three-phase prototype shell-form power transformer. The calculated results show that the largest circulating current in strands of the low-voltage coils near two ends of each phase winding is greatly reduced to 11% from 98% of the rated current in each strand by placing the copper-shielding on these ends.

Cui Xiang; Yuan Jinsha [North China Electric Power Univ., Baoding, Hebei (China). Dept. of Electrical Engineering; Zhang Guoqiang; Zhang Yuanlu; Hu Qifan [Baoding Tian Wei Group Co., Ltd., Baoding, Hebei (China). Div. of Large Power Transformer

1997-03-01T23:59:59.000Z

292

Transformers for explosive pulsed power coupling to various loads  

SciTech Connect

Tape-wound step-up transformers have been fabricated and used with magnetic flux compression generators in the past with effective coupling coefficients of approx.0.76. We have attempted to design some units with coefficients in the range of 0.85 to 0.92 by taking advantage of newer dielectrics. The intent is to raise the voltage stress from less than or equal to 0.39 MV/cm to the range of 0.98 to 1.97 MV/cm. This has the effect of making the secondary thinner and permitting a higher coupling efficiency. Several designs for coupling the 13.2-cm-wide by 52.8-cm-long plate generator to loads in the range of 10 to 30 ..cap omega.. with an output of approx.1 MV have been studied. These designs must take into account that the primary of the transformer is switched into the circuit as a load in parallel with the generator's ballast inductor. A final design examines the constraints imposed by attempting to transform the output of a plate generator up to 10 MV into a high impedance load. A voltage stress of 3.9 MV/cm is required in this particular design for 140 kV per turn in the secondary winding.

Freeman, B.L.; Bostick, W.H.

1986-01-01T23:59:59.000Z

293

Method and apparatus for calibrating a linear variable differential transformer  

DOE Patents (OSTI)

A calibration apparatus for calibrating a linear variable differential transformer (LVDT) having an armature positioned in au LVDT armature orifice, and the armature able to move along an axis of movement. The calibration apparatus includes a heating mechanism with an internal chamber, a temperature measuring mechanism for measuring the temperature of the LVDT, a fixture mechanism with an internal chamber for at least partially accepting the LVDT and for securing the LVDT within the heating mechanism internal chamber, a moving mechanism for moving the armature, a position measurement mechanism for measuring the position of the armature, and an output voltage measurement mechanism. A method for calibrating an LVDT, including the steps of: powering the LVDT; heating the LVDT to a desired temperature; measuring the position of the armature with respect to the armature orifice; and measuring the output voltage of the LVDT.

Pokrywka, Robert J. (North Huntingdon, PA)

2005-01-18T23:59:59.000Z

294

Method and Appartus for Calibrating a Linear Variable Differential Transformer  

DOE Patents (OSTI)

A calibration apparatus for calibrating a linear variable differential transformer (LVDT) having an armature positioned in au LVDT armature orifice, and the armature able to move along an axis of movement. The calibration apparatus includes a heating mechanism with an internal chamber, a temperature measuring mechanism for measuring the temperature of the LVDT, a fixture mechanism with an internal chamber for at least partially accepting the LVDT and for securing the LVDT within the heating mechanism internal chamber, a moving mechanism for moving the armature, a position measurement mechanism for measuring the position of the armature, and an output voltage measurement mechanism. A method for calibrating an LVDT, including the steps of powering the LVDT; heating the LVDT to a desired temperature; measuring the position of the armature with respect to the armature orifice; and measuring the output voltage of the LVDT.

Pokrywka, Robert J.

2005-01-18T23:59:59.000Z

295

High Voltage Electric Discharge Consolidation of Tantalum Powders  

Science Conference Proceedings (OSTI)

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

296

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

Science Conference Proceedings (OSTI)

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

297

(SPS) and High Voltage Electric Discharge Consolidation (HVEDC  

Science Conference Proceedings (OSTI)

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

298

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

Science Conference Proceedings (OSTI)

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

299

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

Science Conference Proceedings (OSTI)

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

300

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

Science Conference Proceedings (OSTI)

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

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


301

Road to AC Voltage Standard Leads to Important Junction  

Science Conference Proceedings (OSTI)

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

2013-08-13T23:59:59.000Z

302

Chronic Benzodiazepine Administration Potentiates High Voltage-Activated Calcium Currents  

E-Print Network (OSTI)

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

Brand, Paul H.

303

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

E-Print Network (OSTI)

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

304

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

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

305

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

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

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

306

Specifying a Low-Voltage Dynamic Sag Corrector  

Science Conference Proceedings (OSTI)

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

2000-11-07T23:59:59.000Z

307

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

Science Conference Proceedings (OSTI)

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

2013-07-30T23:59:59.000Z

308

Medium Voltage Cable Aging Management Guide, Revision 1  

Science Conference Proceedings (OSTI)

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

2010-11-29T23:59:59.000Z

309

Operating standby redundant controller to improve voltage source inverter reliability .  

E-Print Network (OSTI)

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

Blevins, Stephen T.

2007-01-01T23:59:59.000Z

310

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

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

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

311

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

Science Conference Proceedings (OSTI)

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

2013-05-17T23:59:59.000Z

312

Surge Protection in Low-Voltage AC Power Circuits  

Science Conference Proceedings (OSTI)

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

2013-05-20T23:59:59.000Z

313

Optimizing Power Using Transformations  

E-Print Network (OSTI)

: The increasing demand for portable computing has elevated power consumption to be one of the most critical design parameters. A high-level synthesis system, HYPER-LP, is presented for minimizing power consumption in application specific datapath intensive CMOS circuits using a variety of architectural and computational transformations. The synthesis environment consists of high-level estimation of power consumption, a library of transformation primitives, and heuristic/probabilistic optimization search mechanisms for fast and efficient scanning of the design space. Examples with varying degree of computational complexity and structures are optimized and synthesized using the HYPER-LP system. The results indicate that more than an order of magnitude reduction in power can be achieved over current-day design methodologies while maintaining the system throughput; in some cases this can be accomplished while preserving or reducing the implementation area. 1.0 Introduction VLSI research a...

Anantha P. Chandrakasan; Miodrag Potkonjak; Renu Mehra; Jan Rabaey; Robert W. Brodersen

1995-01-01T23:59:59.000Z

314

EPRI Intelligent Universal Transformer  

Science Conference Proceedings (OSTI)

The vision of the EPRI ADA Program (Program 124) is to create the technology basis for the distribution system of the future by transforming traditional single-function distribution systems into multifunctional power and information exchange systems with increased reliability, improved performance (lower system losses), better economics, better power quality, and more customer service options. Achieving this vision will require capturing the benefits of new capabilities in power electronics, information ...

2006-12-18T23:59:59.000Z

315

Grid Transformation Workshop Results  

Science Conference Proceedings (OSTI)

In an earlier white paper entitled Needed: A Grid Operating System to Facilitate Grid Transformation; EPRI; Palo Alto, CA: 2011; 1023223, we set the stage for a new grid operating system called Grid 3.0. Since that time we have identified four core research areas that are required to achieve the expected outcome. These research areas are called: seamless geospatial power system model, seamless power system analytics, integrated energy management system and setting-less protection method. While each area ...

2012-05-08T23:59:59.000Z

316

Rainfall Analysis by Power Transformation  

Science Conference Proceedings (OSTI)

Power transformation was used to normalize the peak daily and peak monthly rainfall at various raingage stations in Iraq. Excellent correlations were found between the coefficient of skewness (Cs) and a parameter for power transformation (?), ...

Hameed Rasheed; A. S. Aldabagh; Murur V. Ramamoorthy

1983-08-01T23:59:59.000Z

317

Yeo-Johnson Power Transformations  

E-Print Network (OSTI)

This paper describes an Arc add-in for using the Yeo-Johnson power transformations in place of the Box-Cox power transformations in various places in Arc. 1

Sanford Weisberg

2001-01-01T23:59:59.000Z

318

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

Science Conference Proceedings (OSTI)

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

2000-06-21T23:59:59.000Z

319

Remarks on restricted Nevanlinna transforms  

E-Print Network (OSTI)

The Nevanlinna transform K(z), of a measure and a real constant, plays an important role in the complex analysis and more recently in the free probability theory (boolean convolution). It is shown that its restriction k(it) (the restricted Nevanlinna transform) to the imaginary axis can be expressed as the Laplace transform of the Fourier transform (characteristic function) of the corresponding measure. Finally, a relation between the Voiculescu and the boolean convolution is indicated.

Jankowski, Lech

2010-01-01T23:59:59.000Z

320

Phase Transformation and Microstructural Evolution  

Science Conference Proceedings (OSTI)

Jul 15, 2013 ... Relationship between Microstructural Evolution, Order-disorder Transformation and Plastic Inhomogeneities during Deformation of Beta Brass.

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


321

Remarks on the conformal transformations  

E-Print Network (OSTI)

Conformal transformations are obtained by demanding that the form of the metric change by a conformal factor. Nevertheless, this transformation of the metric is not taken into account when a variation of the action is performed. The basic purpose of this paper is to take the transformation of the metric into the variation of the action. When this is done, we obtain now that even massive particles are invariant under the conformal transformations.

L. C. T. Guillen

2004-08-10T23:59:59.000Z

322

Remarks on the conformal transformations  

E-Print Network (OSTI)

Conformal transformations are obtained by demanding that the form of the metric change by a conformal factor. Nevertheless, this transformation of the metric is not taken into account when a variation of the action is performed. The basic purpose of this paper is to take the transformation of the metric into the variation of the action. When this is done, we obtain now that even massive particles are invariant under the conformal transformations.

Guillen, L C T

2004-01-01T23:59:59.000Z

323

Applying a Model Transformation Taxonomy to Graph Transformation Technology  

E-Print Network (OSTI)

A taxonomy of model transformations was introduced in [16]. Among others, such a taxonomy can help developers in deciding which language, forma lism, tool or mechanism is best suited to carry out a particular model transformation activity. In this paper we apply the taxonomy to the technique of graph transformation, and we exemplify it by referring to four representative graph transformation tools. As a byproduct of our analysis, we discuss how well each of the considered tools carry out the activity of model transformation.

Tom Mens; Pieter Van Gorp; Dániel Varró; Gabor Karsai

2005-01-01T23:59:59.000Z

324

Local Dynamic Reactive Power for Correction of System Voltage Problems  

SciTech Connect

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

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

2008-12-01T23:59:59.000Z

325

Generalized Transforms and Special Functions  

E-Print Network (OSTI)

We study the properties of different type of transforms by means of operational methods and discuss the relevant interplay with many families of special functions. We consider in particular the binomial transform and its generalizations. A general method, based on the use of the Fourier transform technique, is proposed for the study of the properties of functions of operators.

G. Dattoli; E. Sabia

2010-10-08T23:59:59.000Z

326

A taxonomy of model transformation  

E-Print Network (OSTI)

This report summarises the results of the discussions of a working group on model transformation of the Dagstuhl Seminar on Language Engineering for Model-Driven Software Development. The main contribution is a taxonomy of model transformation. This taxonomy can be used to help developers in deciding which model transformation approach is best suited to deal with a particular problem.

Tom Mens; Krzysztof Czarnecki; Pieter Van Gorp

2005-01-01T23:59:59.000Z

327

Wavelet transform and Radon transform on the Quaternion Heisenberg group  

E-Print Network (OSTI)

Let $\\mathscr Q$ be the quaternion Heisenberg group, and let $\\mathbf P$ be the affine automorphism group of $\\mathscr Q$. We develop the theory of continuous wavelet transform on the quaternion Heisenberg group via the unitary representations of $\\mathbf P$ on $L^2(\\mathscr Q)$. A class of radial wavelets is constructed. The inverse wavelet transform is simplified by using radial wavelets. Then we investigate the Radon transform on $\\mathscr Q$. A Semyanistri-Lizorkin space is introduced, on which the Radon transform is a bijection. We deal with the Radon transform on $\\mathscr Q$ both by the Euclidean Fourier transform and the group Fourier transform. These two treatments are essentially equivalent. We also give an inversion formula by using wavelets, which does not require the smoothness of functions if the wavelet is smooth.

He, JIanxun

2011-01-01T23:59:59.000Z

328

Nonrelativistic conformal transformations in Lagrangian formalism  

E-Print Network (OSTI)

The conformal transformations corresponding to $N$-Galilean conformal symmetries, previously defined as canonical symmetry transformations on phase space, are constructed as point transformations in coordinate space.

Andrzejewski, K; Kijanka-Dec, A

2013-01-01T23:59:59.000Z

329

Robust Design of Basic Low Voltage CMOS Transconductors  

Science Conference Proceedings (OSTI)

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

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

1999-09-01T23:59:59.000Z

330

Motor voltage asymmetry influence to the efficient energy usage  

Science Conference Proceedings (OSTI)

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

Miloje Kostic; Aleksandar Nikolic

2010-07-01T23:59:59.000Z

331

Analysis of Voltage Notching Concerns at a Petroleum Pumping Station  

Science Conference Proceedings (OSTI)

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

2003-12-31T23:59:59.000Z

332

Compile-time dynamic voltage scaling settings: opportunities and limits  

Science Conference Proceedings (OSTI)

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

Fen Xie; Margaret Martonosi; Sharad Malik

2003-06-01T23:59:59.000Z

333

Proceedings: EPRI/NERC Forum on Voltage Stability  

Science Conference Proceedings (OSTI)

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

1993-06-01T23:59:59.000Z

334

Wind Farm Grid Voltage Stability Researching Based on Cascade STATCOM  

Science Conference Proceedings (OSTI)

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

Li Shengqing, Xu Wenxiang, Li Weizhou, Zeng Huanyue

2013-01-01T23:59:59.000Z

335

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

Science Conference Proceedings (OSTI)

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

2012-11-28T23:59:59.000Z

336

Living and Working Safely Around High-Voltage Power Lines.  

Science Conference Proceedings (OSTI)

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

United States. Bonneville Power Administration.

2001-06-01T23:59:59.000Z

337

A Bijective String Sorting Transform  

E-Print Network (OSTI)

Given a string of characters, the Burrows-Wheeler Transform rearranges the characters in it so as to produce another string of the same length which is more amenable to compression techniques such as move to front, run-length encoding, and entropy encoders. We present a variant of the transform which gives rise to similar or better compression value, but, unlike the original, the transform we present is bijective, in that the inverse transformation exists for all strings. Our experiments indicate that using our variant of the transform gives rise to better compression ratio than the original Burrows-Wheeler transform. We also show that both the transform and its inverse can be computed in linear time and consuming linear storage.

Gil, Joseph Yossi

2012-01-01T23:59:59.000Z

338

Lorentz transformations: Einstein's derivation simplified  

E-Print Network (OSTI)

We show that the Lorentz transformations for the space-time coordinates of the same event are a direct consequence of the principle of relativity and of Einstein's distant clocks synchronization procedure. In our approach, imposing the linear character of the Lorentz transformations we guess that the transformation equation for the space coordinate has the form x=ax'+cbt'. Imposing the condition that it accounts for the time dilation relativistic effect and taking into account the fact that due to the clock synchronization a la Einstein the space-time coordinates of the same event in the two frames are related by x=ct and x'=ct', we find out expressions for a and b. Dividing the transformation equation for the space coordinate by c we obtain the transformation equation for the time coordinate t=at'+b/cx'. Combining the two transformation equations we obtain directly the inverse Lorentz transformations.

Bernhard Rothenstein; Stefan Popescu

2007-02-19T23:59:59.000Z

339

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

E-Print Network (OSTI)

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

Pota, Himanshu Roy

340

The feasibility of replacing or upgrading utility distribution transformers during routine maintenance  

SciTech Connect

It is estimated that electric utilities use about 40 million distribution transformers in supplying electricity to customers in the United States. Although utility distribution transformers collectively have a high average efficiency, they account for approximately 61 billion kWh of the 229 billion kWh of energy lost annually in the delivery of electricity. Distribution transformers are being replaced over time by new, more efficient, lower-loss units during routine utility maintenance of power distribution systems. Maintenance is typically not performed on units in service. However, units removed from service with appreciable remaining life are often refurbished and returned to stock. Distribution transformers may be removed from service for many reasons, including failure, over- or underloading, or line upgrades such as voltage changes or rerouting. When distribution transformers are removed from service, a decision must be made whether to dispose of the transformer and purchase a lower-loss replacement or to refurbish the transformer and return it to stock for future use. This report contains findings and recommendations on replacing utility distribution transformers during routine maintenance, which is required by section 124(c) of the Energy Policy Act of 1992. The objectives of the study are to evaluate the practicability, cost-effectiveness, and potential energy savings of replacing or upgrading existing transformers during routine utility maintenance and to develop recommendations on was to achieve the potential energy savings.

Barnes, P.R.; Van Dyke, J.W.; McConnell, B.W.; Cohn, S.M.; Purucker, S.L.

1995-04-01T23:59:59.000Z

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


341

A nonlinear lumped parameter model for transient studies of single-phase core form transformers  

Science Conference Proceedings (OSTI)

Power transformers, in service, are subjected to voltage transients. The transformer insulation should be designed to withstand the internal stresses initiated by these transients. To determine these stresses during the design stage, lumped parameter models of the transformer are employed. Computer models are the best tools for predetermination of these stresses. To date, in spite of the great efforts employed, lack of accurate and consistent transformer models are felt to contribute to the relatively high failure rate of the EHV transformers. This thesis is based on a detailed transformer model developed by G.E. for transformer insulation design. Although this model has provided the designer a suitable tool for transient study during design stage, it assumed a linear characteristic for iron core and employed an empirical method to model damping effect of transformer losses. It is felt that the core`s non-linear magnetic characteristic has an appreciable effect on the transformers transient response. This thesis develops a detailed transformer model which accurately models the nonlinear, saturable, characteristic of transformer magnetic core. The model is based on linearization of the core`s saturable characteristic during each time interval of solution. Then the linear model is solved within that interval and based on the magnetizing flux in the core, the inductance model is adjusted for the next time interval of solution, and the updated linear model is solved for the interval. A stable solution routine is developed to solve the nonlinear model`s system of O.D.E.`s. Supplementary features needed for transformer design such as external circuits, switches and nonlinear resistors are developed for this solution routine. The necessary methods are developed for verification of the linear transformer model in the frequency domain.

Vakilian, M.

1993-12-31T23:59:59.000Z

342

Fast Fourier transform telescope  

Science Conference Proceedings (OSTI)

We propose an all-digital telescope for 21 cm tomography, which combines key advantages of both single dishes and interferometers. The electric field is digitized by antennas on a rectangular grid, after which a series of fast Fourier transforms recovers simultaneous multifrequency images of up to half the sky. Thanks to Moore's law, the bandwidth up to which this is feasible has now reached about 1 GHz, and will likely continue doubling every couple of years. The main advantages over a single dish telescope are cost and orders of magnitude larger field-of-view, translating into dramatically better sensitivity for large-area surveys. The key advantages over traditional interferometers are cost (the correlator computational cost for an N-element array scales as Nlog{sub 2}N rather than N{sup 2}) and a compact synthesized beam. We argue that 21 cm tomography could be an ideal first application of a very large fast Fourier transform telescope, which would provide both massive sensitivity improvements per dollar and mitigate the off-beam point source foreground problem with its clean beam. Another potentially interesting application is cosmic microwave background polarization.

Tegmark, Max; Zaldarriaga, Matias [Department of Physics and MIT Kavli Institute, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Center for Astrophysics, Harvard University, Cambridge, Massachusetts 02138 (United States)

2009-04-15T23:59:59.000Z

343

Applications of an electronic transformer in a power distribution system  

E-Print Network (OSTI)

In electrical power distribution and power electronic applications, a transformer is an indispensable component which performs many functions. At its operating frequency (60/50 Hz), it is one of the most bulky and expensive components. The concept of the electronic transformer introduced previously has shown considerable reduction in size, weight, and volume by operating at a higher frequency. In this dissertation, the concept of the electronic transformer is further extended to the auto-connected phase-shifting type to reduce harmonics generated by nonlinear loads. It is shown that with the addition of primary side and secondary side AC/AC converters achieves phase-shifting. With the addition of converters, magnetic components are operated at a higher frequency to yield a smaller size and weight. Two types of auto-connected electronic transformer configurations are explored. In the first configuration, the secondary converter is eliminated and the output is suitable for rectifier type loads such as adjustable speed drives. In the second configuration, the secondary converter is added to obtain a sinusoidal phase-shifted AC output voltage. This approach is applicable in general applications. With the proposed approaches, the th and 7th harmonic in utility line currents, generated by two sets of nonlinear loads, are subtracted within the electronic transformer, thereby reducing the total harmonic distortion (THD) of the line current. The analysis and simulation results are presented. In the second part of the dissertation, the electronic transformer concept is applied to a telecommunication power supply (-48 VDC) system. The proposed approach consists of a matrix converter to convert the low frequency three-phase input AC utility to a high frequency AC output without a DC-link. The output of the matrix converter is then processed via a high frequency isolation transformer to produce -48 VDC. Digital control of the system ensures that the output voltage is regulated and the input currents are of high quality, devoid of low frequency harmonics and at near unity input power factor under varying load conditions. Due to the absence of DC-link electrolytic capacitors, the power density of the proposed rectifier is shown to be higher. Analysis, design example and experimental results are presented from a three-phase 208 V, 1.5 kW laboratory prototype converter.

Ratanapanachote, Somnida

2004-08-01T23:59:59.000Z

344

LU transformation invariant operators and LU transformation invariant  

E-Print Network (OSTI)

We proposed a concept of LU transformation invariant operators. By using this operator, arbitrary multi-qubit states LU transformation invariant and SLOCC invariant could be easily obtained. And we find that presences two kinds of invariant operators and corresponding invariants. One kind of operators yields LU invariants and the other operators results in SLOCC invariants. For three-qubit states, all independence LU transformation invariant are obtained. Furthermore, by this system method, arbitrary multi-qubit states invariants can be given.

Xin-wei Zha; Chun-min Zhang

2007-02-06T23:59:59.000Z

345

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

E-Print Network (OSTI)

This dissertation addresses three different problems in power systems. The first problem is related to the fault location in complex topologies such as three terminal circuits with series compensation and mutually coupled line sections and distribution networks with distributed generation. Novel methods are presented by using traveling wave approach and wavelet transformation technique to overcome the difficulties introduced by the discontinuities and integrated components such as Metal Oxide Varistor (MOV) protected series capacitors and distributed generation in complex topologies. Simulation results show good correlation between the actual and estimated fault locations for all the studied cases. The second problem concerns the calculation 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 the need to use wave equations and line parameters provided that an electromagnetic Transients Program (EMTP) type transients simulator is available for generating bus voltage transients for a given fault. This is accomplished by developing a time series model to estimate the voltage at an intermediate point along the transmission line. The model is formed for each intermediate point separately. Once the model is obtained it can be used to predict the transient voltage at that point along the line during any fault in the system. The approach can potentially be useful as a post processor to a transient simulator and can be used by developers of transient animations and movies for illustrating fault-initiated propagation of traveling waves in power systems. The third problem is the lack of powerful visualization and animation methods, which can help understanding the complex behavior of power systems during transients. The goal of this part of the dissertation is to develop new animation and visualization methods for power system electromagnetic transients for both educational and research purposes. Proposed approaches are implemented in different environments such as MATLAB and Microsoft Visual Studio to show the effectiveness of two and three-dimensional visualization of power system transients. The implementations of the proposed methods provide better understanding of the power systems during transient phenomena due to the faults or switchings.

Evrenosoglu, Cansin Yaman

2006-12-01T23:59:59.000Z

346

A Survey on the Principle and Control of Dynamic Voltage Restorer  

Science Conference Proceedings (OSTI)

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

Shuhong Kong; Zhongdong Yin; Renzhong Shan; Weidong Shang

2009-10-01T23:59:59.000Z

347

Low-voltage-swing Monolithic DC-DC Conversion  

E-Print Network (OSTI)

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

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

2004-01-01T23:59:59.000Z

348

On-line transformer monitoring  

Science Conference Proceedings (OSTI)

There are presently many different approaches to transformer monitoring, either on the market or under development. There are also, many different opinions about how on-line monitoring should be accomplished. On the one hand, efforts are being made to develop expert systems that monitor all transformer parameters and generate an estimate of overall transformer condition. On the other hand, a large number of transformer monitors, designed to monitor one or two specific parameters are already on the market. Another important factor to consider in choosing a monitor is who receives the information and how it is transmitted. The ultimate transformer monitor should feed into the supervisory control and data acquisition (Scada) system. This paper discusses the various aspects of this issue including asset protection, cost control, dissolved gases, pinpointing bad bushings and current transformers, hot spot measurement partial discharge, and water-in-oil measurements. 10 figs.

NONE

1995-10-01T23:59:59.000Z

349

Spheromak reactor with poloidal flux-amplifying transformer  

DOE Patents (OSTI)

An inductive transformer in the form of a solenoidal coils aligned along the major axis of a flux core induces poloidal flux along the flux core's axis. The current in the solenoidal coil is then reversed resulting in a poloidal flux swing and the conversion of a portion of the poloidal flux to a toroidal flux in generating a spheromak plasma wherein equilibrium approaches a force-free, minimum Taylor state during plasma formation, independent of the initial conditions or details of the formation. The spheromak plasma is sustained with the Taylor state maintained by oscillating the currents in the poloidal and toroidal field coils within the plasma-forming flux core. The poloidal flux transformer may be used either as an amplifier stage in a moving plasma reactor scenario for initial production of a spheromak plasma or as a method for sustaining a stationary plasma and further heating it. The solenoidal coil embodiment of the poloidal flux transformer can alternately be used in combination with a center conductive cylinder aligned along the length and outside of the solenoidal coil. This poloidal flux-amplifying inductive transformer approach allows for a relaxation of demanding current carrying requirements on the spheromak reactor's flux core, reduces plasma contamination arising from high voltage electrode discharge, and improves the efficiency of poloidal flux injection.

Furth, Harold P. (Princeton, NJ); Janos, Alan C. (East Windsor, NJ); Uyama, Tadao (Osaka, JP); Yamada, Masaaki (Lawrenceville, NJ)

1987-01-01T23:59:59.000Z

350

Gassing of Transformers: An Update  

Science Conference Proceedings (OSTI)

Transformers rarely, if ever, operate under equilibrium conditions; rather, they exist in a dynamic state where decomposition products migrate among various phases, including headspace (when present), oil, and solid insulation. Detailed knowledge of these parameters is needed for accurately interpreting fault gas analysis and for continuous transformer condition monitoring. This report describes work to date on laboratory experiments using test chambers to simulate transformer conditions under various dy...

2001-11-26T23:59:59.000Z

351

Transformer Population Model With Testing  

Science Conference Proceedings (OSTI)

EPRI's asset management research focuses on developing a rational basis for selecting repair or replacement options for specific classes of equipment by balancing the risks of equipment failure against the costs of continued maintenance or capital replacement. This Model User Guide is a companion to Transformer Asset Management and Testing Methodology, EPRI, Palo Alto, CA: 2006. 1012504, which discusses methods for making decisions about transformers, and It explicitly models transformer degradation, ins...

2006-12-05T23:59:59.000Z

352

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

Science Conference Proceedings (OSTI)

Electrical power systems in future hybrid and fuel cell vehicles may employ three voltage (14V, 42V and high voltage (HV)) nets. These will be necessary to accommodate existing 14V loads as well as efficiently handle new heavy loads at the 42V net and an electrical traction drive on the HV bus. A low-cost bi-directional dc-dc converter was proposed in (10) for connecting the three voltage nets. The converter consists of two half-bridges and a high-frequency transformer; thus minimizing the number of switching devices and their associated gate driver components. One salient feature is that the half-bridge on the 42V bus is also utilized to provide the 14V bus by operating its duty ratio around an atypical value of 1/3. This eliminates the need for an additional 14V/42V converter. Moreover, it makes use of the parasitic capacitance of the switches and the transformer leakage inductance for soft-switching; no extra active switches or passive resonant components are required. The use of half-bridges makes the topology suitable for interleaved multi-phase configurations as a means to increase the power level because the capacitor legs can be shared. This paper presents simulation and experimental results on an interleaved two-phase arrangement rated at 4.5 kW. Also discussed are the benefits of operating with the atypical duty ratio on the transformer and a preferred multi-phase configuration to minimize capacitor ripple currents.

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

2007-01-01T23:59:59.000Z

353

Phase Transformation and Microstructural Evolution  

Science Conference Proceedings (OSTI)

Jul 31, 2012 ... Yunzhi Wang, Ohio State University. Scope, Phase transformation is still one of the most effective and efficient means to produce desired ...

354

EPRI Transformer Task Force Proceedings  

Science Conference Proceedings (OSTI)

The EPRI Transformer Task Force held a meeting on December 4, 2007, in San Antonio, Texas. This technical update contains the proceedings of the meeting.

2008-02-12T23:59:59.000Z

355

EPRI Transformer Task Force Proceedings  

Science Conference Proceedings (OSTI)

This report contains the proceedings from the EPRI Transformers Task Force, which was held in Montreal on October 26 and 27, 2006.

2006-12-12T23:59:59.000Z

356

Transformations of hypergeometric elliptic integrals  

E-Print Network (OSTI)

The paper classifies algebraic transformations of Gauss hypergeometric functions with the local exponent differences $(1/2,1/4,1/4)$, $(1/2,1/3,1/6)$ and $(1/3,1/3,1/3)$. These form a special class of algebraic transformations of Gauss hypergeometric functions, of arbitrary high degree. The Gauss hypergeometric functions can be identified as elliptic integrals on the genus 1 curves $y=x^3-x$ or $y=x^3-1$. Especially interesting are algebraic transformations of the hypergeometric functions into themselves; these transformations come from isogenies of the respective elliptic curves.

Vidunas, Raimundas

2008-01-01T23:59:59.000Z

357

An investigation of Lorentz transformation  

E-Print Network (OSTI)

A new method of derivation of Lorentz Transformation (LT) is given based on both axioms of special relativity (SR) and physical intuitions. The essence of the transformation is established and the crucial role played by the presumptions is presented for clarification. I consider the most general form of transformations between two sets of events in two inertial reference frames and use the most basic properties expected from such a transformation together with the principle of the constancy of the velocity of light to derive LT. The method is very simple, succinct and useful for students trying a better understanding of the subject.

Farid Shahandeh

2013-04-13T23:59:59.000Z

358

FOURIER TRANSFORM MULTIPLE QUANTUM NMR  

E-Print Network (OSTI)

TRANSFORM MULTIPLE QUANTUM NMR G. Drobny, A. Pines, S.TRANSFO~~ MULTIPLE QUANTUM NMR G. Drobny, A. Pines, S.

Drobny, G.

2011-01-01T23:59:59.000Z

359

Reliability centered maintenance of power transformers and circuit breakers  

SciTech Connect

At the Bonneville Power Administration (BPA), we have historically maintained high voltage equipment. Including transformers and power circuit breakers, on a time driven basis. While this has served our needs in the past, newer methods are needed to effectively maintain the power system in future years. Today aging equipment, maintenance backlogs, and budget constraints are a reality. BPA has initiated a research and development project to examine reliability centered maintenance (RCM) as an alternative to time based maintenance on high voltage equipment. Under RCM, the performance of each place of equipment is to be monitored by observing many operating parameters. For example, with circuit breakers we will observe (measure) the trip time, accumulated contact wear using I{sup 2}T, timing of the mechanism, plus several other parameters. Equipment performing below a predetermined level, or equipment having accumulated a large amount of ``usage`` will receive maintenance. The maintenance will restore full performance and preserve an acceptable service life for that piece of equipment. To develop and evaluate RCM concepts, BPA is installing a prototype system at our Alvey Substation on 4 transformers and 25 breakers.

Purucker, S.L.; Goeltz, R.T. [Oak Ridge National Lab., TN (United States); Hemmelman, K.; Price, R. [Bonneville Power Administration, Van Couver, WA (United States)

1992-08-01T23:59:59.000Z

360

Business Transformation Workbench: A Practitioner's Tool for Business Transformation  

Science Conference Proceedings (OSTI)

Business transformation is a key management initiative that attempts to align people, process and technology of an enterprise more closely with its business strategy and vision. It is an essential part of the competitive business cycle. Existing consulting ... Keywords: business transformation, business process models, software tools

Juhnyoung Lee; Rama Akkiraju; Chun Hua Tian; Shun Jiang; Sivaprashanth Danturthy; Ponn Sundhararajan; Carl Nordman; Rakesh Mohan; Hitansh Singala; Wei Ding

2008-07-01T23:59:59.000Z

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


361

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

Science Conference Proceedings (OSTI)

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

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

2007-09-01T23:59:59.000Z

362

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

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

363

NIST Online Museum of Quantum Voltage Standards, 1970s  

Science Conference Proceedings (OSTI)

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

2011-03-30T23:59:59.000Z

364

Fusing strategies for the dual-voltage fault  

E-Print Network (OSTI)

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

Shrivastava, Rupam, 1981-

2005-01-01T23:59:59.000Z

365

Functionalized High Voltage Spinel Composite for High Power ...  

Science Conference Proceedings (OSTI)

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

366

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

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

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

367

Multilevel cascade voltage source inverter with seperate DC sources  

SciTech Connect

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

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

1997-01-01T23:59:59.000Z

368

Multilevel cascade voltage source inverter with seperate DC sources  

DOE Patents (OSTI)

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

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

2002-01-01T23:59:59.000Z

369

Design & Fabrication of a High-Voltage Photovoltaic Cell  

DOE Green Energy (OSTI)

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

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

2012-09-05T23:59:59.000Z

370

Robust Design of Basic Low Voltage CMOS Transconductors  

Science Conference Proceedings (OSTI)

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

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

1999-09-01T23:59:59.000Z

371

Quartz crystal microbalance based on passive frequency to voltage converter  

SciTech Connect

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

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

2012-02-15T23:59:59.000Z

372

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

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

373

Multilevel cascade voltage source inverter with separate DC sources  

DOE Patents (OSTI)

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

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

1997-06-24T23:59:59.000Z

374

Time varying voltage combustion control and diagnostics sensor  

DOE Patents (OSTI)

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

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

2011-04-19T23:59:59.000Z

375

Light Flicker in Compact Fluorescent Lamps Caused by Voltage Fluctuations  

Science Conference Proceedings (OSTI)

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

2003-12-31T23:59:59.000Z

376

Elevated Neutral to Earth and Contact Voltages in Distribution Systems  

Science Conference Proceedings (OSTI)

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

2008-12-18T23:59:59.000Z

377

INTENSITY OF BETATRON RADIATION AS FUNCTION OF INJECTION VOLTAGE  

SciTech Connect

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

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

1962-09-01T23:59:59.000Z

378

Chloromethyl chlorosulfate as a voltage delay inhibitor in lithium cells  

DOE Patents (OSTI)

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

Delnick, F.M.

1991-04-05T23:59:59.000Z

379

Cable Aging Management Training Course for Low-Voltage Cables  

Science Conference Proceedings (OSTI)

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

2003-11-24T23:59:59.000Z

380

Optical control system for high-voltage terminals  

DOE Patents (OSTI)

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

Bicek, John J. (Tinley Park, IL)

1978-01-01T23:59:59.000Z

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


381

Chloromethyl chlorosulfate as a voltage delay inhibitor in lithium cells  

DOE Patents (OSTI)

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

Delnick, Frank M. (Albuquerque, NM)

1993-01-01T23:59:59.000Z

382

Chloromethyl chlorosulfate as a voltage delay inhibitor in lithium cells  

DOE Patents (OSTI)

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

Delnick, F.M.

1993-04-13T23:59:59.000Z

383

Measuring Helical FCG Voltage with an Electric Field Antenna  

SciTech Connect

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

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

2011-08-01T23:59:59.000Z

384

High voltage series connected tandem junction solar battery  

DOE Patents (OSTI)

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

Hanak, Joseph J. (Lawrenceville, NJ)

1982-01-01T23:59:59.000Z

385

Definition: Line Transformer Monitors | Open Energy Information  

Open Energy Info (EERE)

Transformer Monitors Transformer Monitors Jump to: navigation, search Dictionary.png Line Transformer Monitors Transformer Monitoring System can monitor different aspects of transformers, including oil levels and multiple temperatures within the transformer. This allows for analysis of the health of either individual key power transformers or multiple power transformers networked in the system. For example, the transformer monitors provide transformer oil dissolved gas analysis (DGA), oil temperature, ambient temperature, and moisture in oil measurements. These measurements are made in relation to transformer load.[1] Related Terms transformer, system, transformer References ↑ https://www.smartgrid.gov/category/technology/line_transformer_monitors [[Cat LikeLike UnlikeLike You like this.Sign Up to see what your friends like.

386

Shaping the output pulse of a linear-transformer-driver module.  

SciTech Connect

We demonstrate that a wide variety of current-pulse shapes can be generated using a linear-transformer-driver (LTD) module that drives an internal water-insulated transmission line. The shapes are produced by varying the timing and initial charge voltage of each of the module's cavities. The LTD-driven accelerator architecture outlined in [Phys. Rev. ST Accel. Beams 10, 030401 (2007)] provides additional pulse-shaping flexibility by allowing the modules that drive the accelerator to be triggered at different times. The module output pulses would be combined and symmetrized by water-insulated radial-transmission-line impedance transformers [Phys. Rev. ST Accel. Beams 11, 030401 (2008)].

Long, Finis W.; McKee, G. Randall; Stoltzfus, Brian Scott; Woodworth, Joseph Ray; McKenney, John Lee; Fowler, William E.; Mazarakis, Michael Gerrassimos; Porter, John L.; Stygar, William A.; Savage, Mark Edward; LeChien, Keith, R.; Van De Valde, David M. (EG& G, Albuquerque, NM)

2008-11-01T23:59:59.000Z

387

Single-transformer substation for 500 kV and over  

SciTech Connect

At extra high voltage substations which must meet high reliability requirements, in particular, two autotransformer groups are often installed almost simultaneously independent of the load. As a result, significant capital investment is frozen for long periods, and scarce electrical equipment is utilized inefficiently. Thus, in a number of cases the construction of substations with a single group of single-phase autotransformers is desirable. In this case, on failure of one autotransformer phase the time of subnormal energy output due to disconnection of the substation may reach several hours. The efficiency of extra high voltage substations may be improved significantly by using a proposed circuit for connection of a group of single-phase transformers with a single reserve phase, permitting installation of one group of single-phase transformers at a substation without impairment of reliability. The installation, performance and cost of this transformer arrangement are discussed. It is concluded that the use of single-transformer 500 kV substations with the proposed circuit as distribution substations would, on the one hand, provide sufficient reliability for users and, on the other hand, would make them competitive with 220 to 330 kV substations. In this case the network reliability can be provided by sectionalizing the lines at the site of transformer connection. This circuit can be used with two-sided substation supply. (LCL)

Gryuntal, Yu.L.; Mikhailov, A.K.; Slavin, G.A.

1978-06-01T23:59:59.000Z

388

Diagnostics Techniques of Power Transformer  

Science Conference Proceedings (OSTI)

This paper provides the information on the diagnostics techniques for condition monitoring of power transformer (PT). This paper deals with the practical importance of the transformer diagnostic in the Electrical Engineering field. A review has been ... Keywords: temperature, condition monitoring, diagnostics methods, paper analysis techniques, oil analysis techniques

Piush Verma; Y. R. Sood; Jashandeep Singh

2009-12-01T23:59:59.000Z

389

Graph Transformations in Relational Databases  

E-Print Network (OSTI)

The theory of graph transformation [2] was originally developed as a generalization of Chomsky grammars from strings to graphs. Methods, techniques, and tools from the area of graph transformations have already been studied and applied in many fields of computer science such as formal language theory, pattern recognition and generation, compiler construction, software engineering, etc. Despite the large variety of existing graph transformation tools, the implementation of their graph transformation engine typically follows the same principle. In this respect, first a matching occurrence of the left-hand side (LHS) of the graph transformation rule is being found by some sophisticated graph pattern matching algorithm. Then the engine performs some local modifications to add or remove graph elements to the matching pattern, and the entire process starts all over again. Since graph pattern matching leads to the subgraph isomorphism problem that is known to be NPcomplete in general, this step is considered to be the most crucial in the overall performance of a graph transformation engine. Current tools (e.g., PROGRES [4]) use different efficient strategies for the graph pattern matching phase. However, I argue that the overall complexity of a graph transformation engine is not necessarily equal to the complexity of the graph pattern matching phase, especially for long transformation sequences.

Gergely Varró

2004-01-01T23:59:59.000Z

390

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

E-Print Network (OSTI)

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

Kline, Jared Andrew

2011-01-01T23:59:59.000Z

391

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

E-Print Network (OSTI)

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

Tamimi, Ala

2011-01-01T23:59:59.000Z

392

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

Science Conference Proceedings (OSTI)

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

2013-01-01T23:59:59.000Z

393

On the fundamental limitations of transformational design  

Science Conference Proceedings (OSTI)

The completeness of a collection of design transformations is an important aspect in transformational design. Completeness guarantees that any correct design can in principle be explored using the transformation system. In the field of transformational ... Keywords: Completeness, formal methods, high-level synthesis, syntactic variance problem, transformational design

Jeroen Voeten

2001-10-01T23:59:59.000Z

394

Research on Differential Protection of Power Transformer Based Wavelet Transform  

Science Conference Proceedings (OSTI)

This article introduces wavelet analysis theory to identify inrush and internal fault correctly. The wavelet transform has the characteristic of multi-scale analysis and good time and frequency domain localization, fits to extract sudden-change signals ...

Yang Long; Li Donghui

2009-10-01T23:59:59.000Z

395

Transformational Manufacturing | Argonne National Laboratory  

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

Transformational Manufacturing Transformational Manufacturing Argonne's new Advanced Battery Materials Synthesis and Manufacturing R&D Program focuses on scalable process R&D to produce advanced battery materials in sufficient quantity for industrial testing. The U.S. manufacturing industry consumes more than 30 quadrillion Btu of energy per year, directly employs about 12 million people and generates another 7 million jobs in related businesses. Argonne is working with industry to develop innovative and transformational technology to improve the efficiency and competitiveness of domestic manufacturing while reducing its carbon footprint. The lab's efforts concentrate on sustainable manufacturing, applied nanotechnology and distributed energy, with an emphasis on transitioning science discoveries to the market.

396

Piezoelectric based high voltage power simulator for implantation  

Science Conference Proceedings (OSTI)

It is based on resonant method that allows the piezoelectric transformer to generate a ... The device is small and with high power density and high efficiency

397

Interaction of Multiple Distributed Energy Resources in Voltage Regulation  

Science Conference Proceedings (OSTI)

Distributed energy resources (DE) with power electronics (PE) interfaces with the right control are capable of providing reactive power related ancillary services; voltage regulation in particular has drawn much attention. In this paper the problem of how to coordinate control multiple DEs to regulate the local voltage in the distribution system is addressed. A control method for voltage regulation using the DE PE controller is presented and based on the proposed control scheme; the voltage regulation of a distribution system with one DE and two DEs are tested, respectively. The factors affecting the gain parameters of the PE controller are investigated. The simulation results show that the parameters of the controller determine its dynamic response for voltage regulation and the factors associated with the network characteristics, such as locations of DEs and the amount of load, affect the impact range of the controller. The research work presented in this paper can be potentially used for the control system design of Smart Grid or Utility of the Future.

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

2008-01-01T23:59:59.000Z

398

Transforms for the Motion Compensation Residual  

E-Print Network (OSTI)

The Discrete-Cosine-Transform (DCT) is the most widely used transform in image and video compression. Its use in image compression is often justified by the notion that it is the statistically optimal transform for first-order ...

Kamisli, Fatih

399

Reusable and correct endogenous model transformations  

Science Conference Proceedings (OSTI)

Correctness of model transformations is a prerequisite for generating correct implementations from models. Given refining model transformations that preserve desirable properties, models can be transformed into correct-by-construction implementations. ...

Suzana Andova; Mark G. J. van den Brand; Luc Engelen

2012-05-01T23:59:59.000Z

400

Mineral Transformation and Biomass Accumulation Associated With  

E-Print Network (OSTI)

Mineral Transformation and Biomass Accumulation Associated With Uranium Bioremediation at Rifle transformation and biomass accumulation, both of which can alter the flow field and potentially bioremediation to understand the biogeochemical processes and to quantify the biomass and mineral transformation/ accumulation

Hubbard, Susan

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


401

Electrokinetic Effects in Power Transformers  

Science Conference Proceedings (OSTI)

Electrokinetic effects such as static electrification can cause catastrophic failures in large forced-oil-cooled power transformers. The development of a network-based theoretical model provides a critical perspective not apparent from previous small-scale laboratory experiments.

1999-08-10T23:59:59.000Z

402

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

DOE Patents (OSTI)

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

Righter, Alan W. (Albuquerque, NM)

1996-01-01T23:59:59.000Z

403

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

Science Conference Proceedings (OSTI)

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

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

2013-05-01T23:59:59.000Z

404

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

DOE Green Energy (OSTI)

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

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

2011-02-01T23:59:59.000Z

405

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

Science Conference Proceedings (OSTI)

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

1993-05-01T23:59:59.000Z

406

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

Science Conference Proceedings (OSTI)

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

Milaim Zabeli; Nebi Caka; Myzafere Limani; Qamil Kabashi

2008-04-01T23:59:59.000Z

407

Experiment Hazard Class 13.0 - High Voltage  

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

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

408

Dynamic Voltage Scaling on a Low-Power Microprocessor  

E-Print Network (OSTI)

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

Johan Pouwelse; Koen Langendoen; Henk Sips

2001-01-01T23:59:59.000Z

409

Proceedings: EPRI/NERC forum on voltage stability  

SciTech Connect

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

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

1993-05-01T23:59:59.000Z

410

Substation distribution transformers failures and spares  

Science Conference Proceedings (OSTI)

Electric utilities should have a sufficient number of spare transformers to backup substation distribution transformers to replace transformers that fail and require factory rebuild or replacement. To identify such a number, the statistical methodology was developed to analyze available failure data for different groups of transformer. That methodology enables the estimation of future numbers of failures with associated probabilities, recommends the proper number of spares, identifies the necessity and shows the means to shorten the transformer`s replacement time.

Kogan, V.I. Roeger, C.J.; Tipton, D.E. [American Electric Power Service Corp., Columbus, OH (United States)

1996-11-01T23:59:59.000Z

411

Inducing Transformational Energy Technological Change  

Science Conference Proceedings (OSTI)

Reducing risks of severe climate change in the latter part of the 20th Century is likely to require not only incremental improvements in known energy technologies, but the discovery of transformational new energy technologies. This paper reviews current knowledge about both demand and supply aspects of the challenge of accelerating transformational change, considering both economic and policy incentives, including targeted government funding of research and development, and several other schools of thought about drivers of scientific discovery and innovation.

Wilbanks, Thomas J [ORNL

2011-01-01T23:59:59.000Z

412

High-Tech Buildings - Market Transformation Project  

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

Tech Buildings - Market Transformation Project Title High-Tech Buildings - Market Transformation Project Publication Type Report LBNL Report Number LBNL-49112 Year of Publication...

413

NREL: Technology Deployment - Deployment and Market Transformation...  

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

Deployment Search More Search Options Site Map Printable Version Deployment and Market Transformation Email Updates NREL's deployment and market transformation email updates...

414

TRANSFORMING ELECTRICITY DELIVERY | Department of Energy  

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

TRANSFORMING ELECTRICITY DELIVERY TRANSFORMING ELECTRICITY DELIVERY Designing research, development, and demonstration programs based on a future look at electric power delivery...

415

National Electric Delivery Technologies Roadmap: Transforming...  

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

Delivery Technologies Roadmap: Transforming the Grid to Revolutionize Electric Power in North America National Electric Delivery Technologies Roadmap: Transforming the Grid to...

416

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

SciTech Connect

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

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

2011-10-10T23:59:59.000Z

417

Voltage Control Devices on the IEEE 8500 Node Test Feeder  

SciTech Connect

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

Schneider, Kevin P.; Fuller, Jason C.

2010-01-06T23:59:59.000Z

418

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

SciTech Connect

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

Brown, William E. (Walnut Creek, CA)

1980-01-01T23:59:59.000Z

419

Directional lapped transforms for image coding  

E-Print Network (OSTI)

Abstract—In this paper, we present the design of directional lapped transforms for image coding. A lapped transform, which can be implemented by a prefilter followed by a discrete cosine transform (DCT), can be factorized into elementary operators. The corresponding directional lapped transform is generated by applying each elementary operator along a given direction. The proposed directional lapped transforms are not only nonredundant and perfectly reconstructed, but they can also provide a basis along an arbitrary direction. These properties, along with the advantages of lapped transforms, make the proposed transforms appealing for image coding. A block-based directional transform scheme is also presented and integrated into HD Phtoto, one of the state-of-the-art image coding systems, to verify the effectiveness of the proposed transforms. Index Terms—Directional transform, image coding, lapped transform.

Jizheng Xu; Feng Wu; Senior Member; Jie Liang; Wenjun Zhang

2008-01-01T23:59:59.000Z

420

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

Science Conference Proceedings (OSTI)

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

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


421

Ultra-compact Marx-type high-voltage generator  

DOE Patents (OSTI)

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

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

2000-01-01T23:59:59.000Z

422

High voltage gas insulated transmission line with continuous particle trapping  

DOE Patents (OSTI)

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

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

1983-01-01T23:59:59.000Z

423

Wire-Extrusion Process Disrupted By Voltage Sags  

Science Conference Proceedings (OSTI)

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

2003-12-31T23:59:59.000Z

424

Smart Solar Home System with Safety Device Low Voltage Alert  

Science Conference Proceedings (OSTI)

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

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

2012-03-01T23:59:59.000Z

425

Current isolating epitaxial buffer layers for high voltage photodiode array  

DOE Patents (OSTI)

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

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

2002-01-01T23:59:59.000Z

426

Design of Low Voltage Low Power Operational Amplifier  

Science Conference Proceedings (OSTI)

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

Manju Sandhu; Manju Bala

2012-01-01T23:59:59.000Z

427

Rank based dynamic voltage and frequency scaling fortiled graphics processors  

Science Conference Proceedings (OSTI)

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

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

2010-10-01T23:59:59.000Z

428

High voltage bipolar-CMOS structure using porous silicon  

DOE Patents (OSTI)

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

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

1990-01-01T23:59:59.000Z

429

Analysis on DFIG Wind Power System Low-Voltage Ridethrough  

Science Conference Proceedings (OSTI)

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

Yulong Wang; Jianlin Li; Shuju Hu; Honghua Xu

2009-04-01T23:59:59.000Z

430

Power and Voltage Smooth Control of Doubly Fed Induction Generator  

Science Conference Proceedings (OSTI)

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

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

2012-07-01T23:59:59.000Z

431

Low-voltage cathodoluminescence of europium-activated yttrium orthovanadate  

Science Conference Proceedings (OSTI)

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

Phillips, M.L.F.

1995-03-01T23:59:59.000Z

432

Control Techniques to Eliminate Voltage Emergencies in High Performance Processors  

E-Print Network (OSTI)

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

Martonosi, Margaret

433

Control Techniques to Eliminate Voltage Emergencies in High Performance Processors  

E-Print Network (OSTI)

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

Gupta, Rajiv

434

High Voltage Laboratory Testing of Femtosecond Laser Lightning Diversion  

Science Conference Proceedings (OSTI)

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

1998-12-09T23:59:59.000Z

435

Stability issues in IC Low Drop Out voltage regulators  

E-Print Network (OSTI)

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

Chava, Krishna Chaitanya

2002-01-01T23:59:59.000Z

436

A variable voltage MPPT control method for photovoltaic generation system  

Science Conference Proceedings (OSTI)

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

Liu Liqun; Wang Zhixin

2009-04-01T23:59:59.000Z

437

Voltage stability/security assessment and on-line control  

SciTech Connect

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

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

1993-04-01T23:59:59.000Z

438

Hierarchical Control Scheme for Voltage Unbalance Compensation in Islanded Microgrids  

E-Print Network (OSTI)

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

Vasquez, Juan Carlos

439

ABDIPOUR A.: ‘Improvement of active microwave device modeling using filter-bank transforms  

E-Print Network (OSTI)

Abstract — A new approach toward global modeling improvement of active microwave devices using filter-bank transforms is presented. A preconditioner based on these transforms is used to facilitate the iterative solution of the Poisson’s equation. This equation must be solved in the excitation plane which the input voltage is applied, at each time step in the full-wave analysis of high-frequency active devices. The condition number of the preconditioned matrix and computational cost of the proposed method is better than the conventional (ILU) and wavelet-based preconditioners. This paper also presents a fundamental step toward applying filter-bank transforms to Maxwell’s equations in conjunction with the hydrodynamic model in implicit schemes, aiming to decrease the simulation time of global modeling. I.

Masoud Movahhedi; Abdolali Abdipour

2005-01-01T23:59:59.000Z

440

An approach for exploring code improving transformations  

Science Conference Proceedings (OSTI)

Although code transformations are routinely applied to improve the performance of programs for both scalar and parallel machines, the properties of code-improving transformations are not well understood. In this article we present a framework that enables ... Keywords: automatic generation of optimizers, code-improving transformations, enabling and disabling of optimizations, parallelizing transformations, specification of program optimizations

Deborah L. Whitfield; Mary Lou Soffa

1997-11-01T23:59:59.000Z

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


441

Transform Solar | Open Energy Information  

Open Energy Info (EERE)

Transform Solar Transform Solar Jump to: navigation, search Name Transform Solar Place Boise, Idaho Product Idaho-based PV module maker and joint venture between Micron and Origin Energy. Coordinates 43.60698°, -116.193409° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":43.60698,"lon":-116.193409,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

442

Towards a Number Theoretic Discrete Hilbert Transform  

E-Print Network (OSTI)

This paper presents an approach for the development of a number theoretic discrete Hilbert transform. The forward transformation has been applied by taking the odd reciprocals that occur in the DHT matrix with respect to a power of 2. Specifically, the expression for a 16-point transform is provided and results of a few representative signals are provided. The inverse transform is the inverse of the forward 16-point matrix. But at this time the inverse transform is not identical to the forward transform and, therefore, our proposed number theoretic transform must be taken as a provisional result.

Kandregula, Renuka

2009-01-01T23:59:59.000Z

443

Transforming quantum operations: quantum supermaps  

E-Print Network (OSTI)

We introduce the concept of quantum supermap, describing the most general transformation that maps an input quantum operation into an output quantum operation. Since quantum operations include as special cases quantum states, effects, and measurements, quantum supermaps describe all possible transformations between elementary quantum objects (quantum systems as well as quantum devices). After giving the axiomatic definition of supermap, we prove a realization theorem, which shows that any supermap can be physically implemented as a simple quantum circuit. Applications to quantum programming, cloning, discrimination, estimation, information-disturbance trade-off, and tomography of channels are outlined.

G. Chiribella; G. M. D'Ariano; P. Perinotti

2008-04-01T23:59:59.000Z

444

Amorphous Metal Transformer: Next Steps  

Science Conference Proceedings (OSTI)

Amorphous-metal transformers were developed through EPRI in the early 1980's. Over the next 15 years, US electric utilities bought and installed over 500,000 units and had satisfactory field experience. The demand for this product disappeared in North America late in the 1990's as deregulation set-in. Globally, this product has been in use, and its acceptance has been increasing. This paper describes the current state of amorphous transformer activities globally. An analysis using US Department of Energy...

2009-07-31T23:59:59.000Z

445

Conditioned Unitary Transformation on biphotons  

E-Print Network (OSTI)

A conditioned unitary transformation ($90^o$ polarization rotation) is performed at single-photon level. The transformation is realized by rotating polarization for one of the photons of a polarization-entangled biphoton state (signal photon) by means of a Pockel's cell triggered by the detection of the other (idler) photon after polarization selection. As a result, polarization degree for the signal beam changes from zero to the value given by the idler detector quantum efficiency. This result is relevant to practical realization of various quantum information schemes and can be used for developing a new method of absolute quantum efficiency calibration.

G. Brida; M. Chekhova; M. Genovese; M. Gramegna; L. Krivitsky; S. Kulik

2003-12-29T23:59:59.000Z

446

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

DOE Patents (OSTI)

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

Humphreys, D.R.

1982-09-15T23:59:59.000Z

447

Online Monitoring Technical Basis and Analysis Framework for Large Power Transformers; Interim Report for FY 2012  

SciTech Connect

The Light Water Reactor Sustainability program at Idaho National Laboratory (INL) is actively conducting research to develop and demonstrate online monitoring (OLM) capabilities for active components in existing Nuclear Power Plants. A pilot project is currently underway to apply OLM to Generator Step-Up Transformers (GSUs) and Emergency Diesel Generators (EDGs). INL and the Electric Power Research Institute (EPRI) are working jointly to implement the pilot project. The EPRI Fleet-Wide Prognostic and Health Management (FW-PHM) Software Suite will be used to implement monitoring in conjunction with utility partners: the Shearon Harris Nuclear Generating Station (owned by Duke Energy for GSUs, and Braidwood Generating Station (owned by Exelon Corporation) for EDGs. This report presents monitoring techniques, fault signatures, and diagnostic and prognostic models for GSUs. GSUs are main transformers that are directly connected to generators, stepping up the voltage from the generator output voltage to the highest transmission voltages for supplying electricity to the transmission grid. Technical experts from Shearon Harris are assisting INL and EPRI in identifying critical faults and defining fault signatures associated with each fault. The resulting diagnostic models will be implemented in the FW-PHM Software Suite and tested using data from Shearon-Harris. Parallel research on EDGs is being conducted, and will be reported in an interim report during the first quarter of fiscal year 2013.

Nancy J. Lybeck; Vivek Agarwal; Binh T. Pham; Heather D. Medema; Kirk Fitzgerald

2012-09-01T23:59:59.000Z

448

The development of coil short circuits when transformer windings become contaminated with metal-containing colloidal particles  

SciTech Connect

The radiational-thermal development of coil short circuits due to the action of partial discharges of the first kind when the windings of transformers, autotransformers and shunting reactors become contaminated with metal-containing colloidal particles, formed in the transformer oil as a result of the interaction of the oil with the constructional materials (the copper of the windings, the iron of the tank, the core etc.) is considered. Acriterion of dangerous contamination of the coil insulation of the windings by metal-containing colloidal particles is proposed, namely, 3% of the mass content of copper and iron in it, which, if exceeded, may serve as a basis for recognizing the state of transformers, autotransformers and shunting reactors at a voltage of 110 kV and above the limit. It is shown that filters for continuously cleaning the oil play a considerable role in prolonging the life of transformer equipment.

L'vov, S. Yu. ['Presselektro' Ltd. (Russian Federation); Lyut'ko, E. O. [JSC 'R and D Center for Power Engineering' (Russian Federation); Bondareva, V. N.; Komarov, V. B. [Russian Academy of Sciences, A. N. Frumkin Institute of Physical Chemistry and Electrochemistry (Russian Federation); L'vov, Yu. N. [JSC 'R and D Center for Power Engineering' (Russian Federation)

2012-01-15T23:59:59.000Z

449

Image capture system colors transforms  

Science Conference Proceedings (OSTI)

The goal of this paper is to simulate the colors transforms of the reflected light from an illuminated object that passes trough an image capture system. We are interested to see the colors differences at the output of each component from which the light ... Keywords: CIE standards, human eye response, lenses and filters transmittance, spectral images

Toadere Florin

2010-02-01T23:59:59.000Z

450

Coupled diffusional/displacive transformations  

E-Print Network (OSTI)

.~...., 0 OJII <- OM -1G1d /J mole Figure 2.2: Illustration of the dependence of interfacial composition x I on the interfacial dissipation Gid for a Fe-0.2C wt.% transformed at 486 QC . Bl and B2 are the coefficients...

Mujahid, Shafiq Ahmad

451

Scalable spectral transforms at petascale  

Science Conference Proceedings (OSTI)

In this paper, I describe a framework for spectral transforms called P3DFFT, and its extended features and applications. I discuss the scaling seen on petascale platforms, and directions and some results of the ongoing work on improving performance, ... Keywords: community applications, high performance computing (HPC), numerical libraries, open source software, parallel performance, petascale, scalability, two-dimensional decomposition

Dmitry Pekurovsky

2013-07-01T23:59:59.000Z

452

Filter Properties of Spectral transformations  

Science Conference Proceedings (OSTI)

Recently, a special group of global spherical coordinate transformations has been introduced in order to focus attention on the interactions of an enlarged spectral band of only one selected area, while de-focusing the rest of the globe and thus ...

Frank Schmidt

1981-02-01T23:59:59.000Z

453

Security-oriented program transformations  

Science Conference Proceedings (OSTI)

Security experts generally believe that, "security cannot be added on, it must be designed from the beginning" [1]. This is because the typical way of improving system security by patches is ad hoc and has not produced good results. My work shows that ... Keywords: program transformation, security

Munawar Hafiz; Ralph E. Johnson

2009-04-01T23:59:59.000Z

454

Guidelines for Working at Voltages < 240 Volts  

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

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

455

Methods for improving solar cell open circuit voltage  

DOE Patents (OSTI)

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

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

1979-01-01T23:59:59.000Z

456

Blocking diodes and fuses in low-voltage PV systems  

DOE Green Energy (OSTI)

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

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

1997-11-01T23:59:59.000Z

457

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

SciTech Connect

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

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

2010-09-29T23:59:59.000Z

458

SRAM leakage suppression by minimizing standby supply voltage  

E-Print Network (OSTI)

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

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

2004-01-01T23:59:59.000Z

459

Analysis of Solar Cell Quality Using Voltage Metrics: Preprint  

DOE Green Energy (OSTI)

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

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

2012-06-01T23:59:59.000Z

460

Field Guide: Compressors for High-Voltage Circuit Breakers  

Science Conference Proceedings (OSTI)

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

2010-12-22T23:59:59.000Z

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


461

Field Guide: Compressors for High-Voltage Circuit Breakers  

Science Conference Proceedings (OSTI)

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

2012-12-14T23:59:59.000Z

462

Nano-Composite Dielectrics on Medium-Voltage Model Cables  

Science Conference Proceedings (OSTI)

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

2007-12-19T23:59:59.000Z

463

High Voltage Direct Current (HVDC) Transmission Reference Book  

Science Conference Proceedings (OSTI)

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

2012-12-31T23:59:59.000Z

464

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

Science Conference Proceedings (OSTI)

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

2013-12-19T23:59:59.000Z

465

Advanced Voltage Control Strategies for High Penetration of Distributed Generation  

Science Conference Proceedings (OSTI)

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

2010-12-31T23:59:59.000Z

466

High-Voltage Direct Current Line Conductor Optimization  

Science Conference Proceedings (OSTI)

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

2011-12-21T23:59:59.000Z

467

Fiber optic current monitor for high-voltage applications  

DOE Patents (OSTI)

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

Renda, G.F.

1992-04-21T23:59:59.000Z

468

765kV Transmission line Voltage gradient  

E-Print Network (OSTI)

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

unknown authors

2012-01-01T23:59:59.000Z

469

Advanced Gate Drive for the SNS High Voltage Converter Modulator  

SciTech Connect

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

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

2009-05-07T23:59:59.000Z

470

Understanding the unbalanced-voltage problem in wind turbine generation  

DOE Green Energy (OSTI)

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

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

2000-02-28T23:59:59.000Z

471

Ultra-low voltage resonant tunnelling diode electroabsorption modulator  

E-Print Network (OSTI)

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

Figueiredo, J M L; Stanley, C R

2002-01-01T23:59:59.000Z

472

Near independence of OLED operating voltage on transport layer thickness  

SciTech Connect

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

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

2013-01-01T23:59:59.000Z

473

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

Science Conference Proceedings (OSTI)

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

Bao Wei; Yin Zhongdong

2009-10-01T23:59:59.000Z

474

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

E-Print Network (OSTI)

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

Moawwad, Ahmed

475

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

Science Conference Proceedings (OSTI)

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

476

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

E-Print Network (OSTI)

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

Guyton, Matthew C. (Matthew Christopher)

2010-01-01T23:59:59.000Z

477

A low-noise bandgap voltage reference employing dynamic element matching  

E-Print Network (OSTI)

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

Herbst, Steven (Steven G.)

2011-01-01T23:59:59.000Z

478

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

Science Conference Proceedings (OSTI)

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

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

2012-01-01T23:59:59.000Z

479

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

Science Conference Proceedings (OSTI)

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

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

2004-04-01T23:59:59.000Z

480

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

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

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


481

Nuclear Maintenance Application Center: Development and Analysis of an Open Phase Detection Scheme for Various Configurations of Auxiliary Transformers  

Science Conference Proceedings (OSTI)

Two recent failures have highlighted the need to detect open-phase conditions that can occur in the power delivery system. The analysis described in this report was performed to determine the response of system auxiliary transformers during open-phase conditions to aid in the development of system protection schemes to detect such conditions.BackgroundIn January 2012, an auxiliary component tripped due to a bus under-voltage. The cause of the event was the ...

2013-05-10T23:59:59.000Z

482

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

Science Conference Proceedings (OSTI)

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

2010-11-29T23:59:59.000Z

483

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

Science Conference Proceedings (OSTI)

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

2012-12-31T23:59:59.000Z

484

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

Science Conference Proceedings (OSTI)

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

G. Pasetti; L. Fanucci; R. Serventi

2010-03-01T23:59:59.000Z

485

Intelligent robust control of hybrid distributed generation system under voltage sag  

Science Conference Proceedings (OSTI)

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

Amin Hajizadeh; Masoud Aliakbar Golkar

2010-12-01T23:59:59.000Z

486

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

Science Conference Proceedings (OSTI)

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

Mustafa Farhadi, Ahmed Mohamed, Osama Mohammed

2013-04-01T23:59:59.000Z

487

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

Science Conference Proceedings (OSTI)

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

Rosli Omar; Nasrudin Abdul Rahim

2011-04-01T23:59:59.000Z

488

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

E-Print Network (OSTI)

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

Czarnecki, Leszek S.

489

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

E-Print Network (OSTI)

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

Pedram, Massoud

490

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

DOE Patents (OSTI)

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

Praeg, W.F.

1975-11-25T23:59:59.000Z

491

Analysis the operation of DVR in voltage sag mitigation using EMTP  

Science Conference Proceedings (OSTI)

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

H. Monsef; B. Tamimi

2005-03-01T23:59:59.000Z

492

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

E-Print Network (OSTI)

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

Pota, Himanshu Roy

493

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

Science Conference Proceedings (OSTI)

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

Jincheol Yoo; Kyusun Choi; Jahan Ghaznavi

2003-04-01T23:59:59.000Z

494

Novel Sensor for Transformer Diagnosis  

Science Conference Proceedings (OSTI)

This report details the progress made in the detection of acetylene and hydrogen gas dissolved in oil using novel methods of optical fiber sensing. Of note in this report are the sensitivity and resolution enhancements of the two sensing methods as well as the construction of a field-testable prototype. The sensor’s non-sensitivity to several other gases commonly found in insulating transformer oil is also described. With some further development, the resolution of gas detection can still be ...

2012-12-12T23:59:59.000Z

495

Entanglement transformations using separable operations  

E-Print Network (OSTI)

We study conditions for the deterministic transformation $\\ket{\\psi}\\longrightarrow\\ket{\\phi}$ of a bipartite entangled state by a separable operation. If the separable operation is a local operation with classical communication (LOCC), Nielsen's majorization theorem provides necessary and sufficient conditions. For the general case we derive a necessary condition in terms of products of Schmidt coefficients, which is equivalent to the Nielsen condition when either of the two factor spaces is of dimension 2, but is otherwise weaker. One implication is that no separable operation can reverse a deterministic map produced by another separable operation, if one excludes the case where the Schmidt coefficients of $\\ket{\\psi}$ and are the same as those of $\\ket{\\phi}$. The question of sufficient conditions in the general separable case remains open. When the Schmidt coefficients of $\\ket{\\psi}$ are the same as those of $\\ket{\\phi}$, we show that the Kraus operators of the separable transformation restricted to the supports of $\\ket{\\psi}$ on the factor spaces are proportional to unitaries. When that proportionality holds and the factor spaces have equal dimension, we find conditions for the deterministic transformation of a collection of several full Schmidt rank pure states $\\ket{\\psi_j}$ to pure states $\\ket{\\phi_j}$.

Vlad Gheorghiu; Robert B. Griffiths

2007-05-02T23:59:59.000Z

496

Nonlinear transform coding with lossless polar coordinates  

E-Print Network (OSTI)

In conventional transform coding, the importance of preserving desirable quantization partition cell shapes prevents one from considering the use of a nonlinear change of variables. If no linear transformation of a given ...

Ba, Demba Elimane

2006-01-01T23:59:59.000Z

497

Transforms for prediction residuals in video coding  

E-Print Network (OSTI)

Typically the same transform, the 2-D Discrete Cosine Transform (DCT), is used to compress both image intensities in image coding and prediction residuals in video coding. Major prediction residuals include the motion ...

Kam??l?, Fatih

2010-01-01T23:59:59.000Z

498

Numerical Transform Inversion Using Gaussian Quadrature  

Science Conference Proceedings (OSTI)

Numerical inversion of Laplace transforms is a powerful tool in computational probability. It greatly enhances the applicability of stochastic models in many fields. In this article we present a simple Laplace transform inversion algorithm that can compute ...

Peter Den Iseger

2006-01-01T23:59:59.000Z

499

Vertical Normal Mode Transforms: Theory and Application  

Science Conference Proceedings (OSTI)

The separation of the vertical structure of the, solutions of the primitive (hydrostatic) meteorological equations is formalized as a vertical normal-mode transform. The transform is implemented for arbitrary static stability profiles by the ...

Scott R. Fulton; Wayne H. Schubert

1985-04-01T23:59:59.000Z

500

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

E-Print Network (OSTI)

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

Joh, Jungwoo