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Note: This page contains sample records for the topic "loss torque converter" 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

Converting a commercial electric direct-drive robot to operate from joint torque commands  

SciTech Connect

Many robot control algorithms for high performance in-contact operations including hybrid force/position, stiffness control and impedance control approaches require the command the joint torques. However, most commercially available robots do not provide joint torque command capabilities. The joint command at the user level is typically position or velocity and at the control developer level is voltage, current, or pulse-width, and the torque generated is a nonlinear function of the command and joint position. To enable the application of high performance in-contact control algorithms to commercially available robots, and thereby facilitate technology transfer from the robot control research community to commercial applications, an methodology has been developed to linearize the torque characteristics of electric motor-amplifier combinations. A four degree of freedom Adept 2 robot, having pulse-width modulation amplifiers and both variable reluctance and brushless DC motors, is converted to operate from joint torque commands to demonstrate the methodology. The commercial robot controller is replaced by a VME-based system incorporating special purpose hardware and firmware programmed from experimental data. The performance improvement is experimentally measured and graphically displayed using three-dimensional plots of torque vs command vs position. The average percentage torque deviation over the command and position ranges is reduced from as much as 76% to below 5% for the direct-drive joints 1, 2 and 4 and is cut by one half in the remaining ball-screw driven joint 3. Further, the torque deviation of the direct-drive joints drops below 2.5% if only the upper 90% of the torque range is considered. 23 refs., 20 figs., 2 tabs.

Muir, P.F.

1991-07-01T23:59:59.000Z

2

Report on Toyota/Prius Motor Torque-Capability, Torque-Property, No-Load Back EMF, and Mechanical Losses  

SciTech Connect

In today's hybrid vehicle market, the Toyota Prius drive system is currently considered the leader in electrical, mechanical, and manufacturing innovations. It is significant that in today's marketplace, Toyota is able to manufacture and sell the vehicle for a profit. This project's objective is to test the torque capability of the 2004 Prius motor and to analyze the torque properties relating to the rotor structure. The tested values of no-load back electromotive force (emf) and mechanical losses are also presented.

Hsu, J.S.

2004-09-30T23:59:59.000Z

3

Report on Toyota/Prius Motor Torque Capability, Torque Property, No-Load Back EMF, and Mechanical Losses, Revised May 2007  

Science Conference Proceedings (OSTI)

In today's hybrid vehicle market, the Toyota/Prius drive system is currently considered the leader in electrical, mechanical, and manufacturing innovations. It is significant that in today's marketplace, Toyota is able to manufacture and sell the vehicle for a profit. This project's objective is to test the torque capability of the 2004 Prius motor and to analyze the torque properties relating to the rotor structure. The tested values of no-load back electromotive force (emf) and mechanical losses are also presented.

Hsu, J.S.; Ayers, C.W.; Coomer, C.L.; Wiles, R.H.; Burress, T.A.; Campbell, S.L.; Lowe, K.T.; Michelhaugh, R.T.

2007-05-31T23:59:59.000Z

4

Digital multimode buck converter control with loss-minimizing synchronous rectifier adaptation  

E-Print Network (OSTI)

Abstract—This paper develops a multimode control strategy which allows for efficient operation of the buck converter over a wide load range. A method for control of synchronous rectifiers as a direct function of the load current is introduced [1]. The function relating the synchronous-rectifier timing to the load current is optimized on-line with a gradient power-loss-minimizing algorithm. Only low-bandwidth measurements of the load current and a power-loss-related quantity are required, making the technique suitable for digital controller implementations. Compared to alternative loss-minimizing approaches, this method has superior adjustment speed and robustness to disturbances, and can simultaneously optimize multiple parameters. The proposed synchronous-rectifier control also accomplishes an automatic, optimal transition to discontinuous-conduction mode at light load. Further, by imposing a minimum duty-ratio, the converter automatically enters pulse-skipping mode at very light load. Thus, the same controller structure can be used in both fixed-frequency pulsewidth modulation and variable-frequency pulse-skipping modes. These techniques are demonstrated on a digitally-controlled 100-W buck converter. Index Terms—Adaptive control, dead-time, digital control, gradient methods, multimode control, optimization methods, pulse skipping, pulsewidth modulated (PWM) power converters, pulsewidth modulation (PWM), synchronous rectifier (SR), variable frequency control. Fig. 1. Buck converter with SR (M), and the corresponding MOSFET control signals.

Angel V. Peterchev; Seth R. S

2006-01-01T23:59:59.000Z

5

Low-noise sigma-delta capacitance-to-digital converter for Sub-pF capacitive sensors with integrated dielectric loss measurement  

Science Conference Proceedings (OSTI)

A sigma-delta capacitance-to-digital converter (CDC) with a resolution down to 19.3 aF at a bandwidth of 10 kHz, corresponding to a noise level of 0.2 aF/?Hz, is presented. An integrated dielectric loss measurement circuit by means of two parallel ...

Markus Bingesser; Teddy Loeliger; Werner Hinn; Johann Hauer; Stefan Mödl; Robert Dorn; Matthias Völker

2008-03-01T23:59:59.000Z

6

Onverter Center of Gravity and Tilting Torque Dynamic Model Simulation  

Science Conference Proceedings (OSTI)

Using SolidWorks software to3D solid modeling of steelmaking converter and liquid steel to get their center of gravity coordinates, so as to optimize the location of the trunnion, that used to determine the best location of the converter trunnion. Based ... Keywords: Converter, Optimization, Tilting, Torque

Lichen Li, Yunfeng Liu, Shaoqing Ren, Tongqing Li

2012-07-01T23:59:59.000Z

7

Abstract--An improvement to the precision of losses calculation in static converters used in a hybrid renewable  

E-Print Network (OSTI)

losses of the wind turbine (WT), diesel generator (DG) and photovoltaic (PV) panels are estimated the required power to the load. The system is shown in Fig. 1. G G = ~ = = Diesel Generator Wind Turbine and the other is a single-phase step-up transformer that connects the inverter output to the system electric

Paris-Sud XI, Université de

8

Fabricated torque shaft  

DOE Patents (OSTI)

A fabricated torque shaft is provided that features a bolt-together design to allow vane schedule revisions with minimal hardware cost. The bolt-together design further facilitates on-site vane schedule revisions with parts that are comparatively small. The fabricated torque shaft also accommodates stage schedules that are different one from another in non-linear inter-relationships as well as non-linear schedules for a particular stage of vanes.

Mashey, Thomas Charles (Anderson, SC)

2002-01-01T23:59:59.000Z

9

Reduction in iron losses in Indirect Vector-Controlled IM Drive using FLC  

E-Print Network (OSTI)

This paper describes the use of fuzzy logic controller for efficiency optimization control of a drive while keeping good dynamic response. At steady-state light-load condition, the fuzzy controller adaptively adjusts the excitation current with respect to the torque current to give the minimum total copper and iron loss. The measured input power such that, for a given load torque and speed, the drive settles down to the minimum input power, i.e., operates at maximum efficiency. The low-frequency pulsating torque due to decrementation of flux is compensated in a feed forward manner. If the load torque or speed commands changes, the efficiency search algorithm is abandoned and the rated flux is established to get the best dynamic response. The drive system with the proposed efficiency optimization controller has been simulated with lossy models of converter and machine, and its performance has been thoroughly investigated.

Srisailam, C; Trivedi, Anurag

2010-01-01T23:59:59.000Z

10

Theory of Spin Transfer Torque  

Science Conference Proceedings (OSTI)

... In the phenomenon known as spin transfer torque, a current can give a jolt to thin magnetic layers sandwiched between nonmagnetic materials. ...

2013-06-28T23:59:59.000Z

11

Centrifugal torque in rotating matter  

E-Print Network (OSTI)

Thermal molecular motion in combination with rotation and differences in centrifugal forces causes a torque in matter. The effect is derived for gas but does also exist in liquid and solid matter.

Jonsson, David

2010-01-01T23:59:59.000Z

12

Torques in atmospheres of rotating planets  

E-Print Network (OSTI)

Molecular motion in combination with planetary rotation and gravity causes a torque in gas when seen from a coordinate system fixed in the planet. The torque is caused by the difference in centrifugal forces when gas molecules are moving along or opposite to the planets rotation.

Jonsson, David

2010-01-01T23:59:59.000Z

13

RADIOACTIVE MATERIAL PACKAGING TORQUE REQUIREMENTS COMPLIANCE  

Science Conference Proceedings (OSTI)

Shipping containers used to transport radioactive material (RAM) in commerce employ a variety of closure mechanisms. Often, these closure mechanisms require a specific amount of torque be applied to a bolt, nut or other threaded fastener. It is important that the required preload is achieved so that the package testing and analysis is not invalidated for the purpose of protecting the public. Torque compliance is a means of ensuring closure preload, is a major factor in accomplishing the package functions of confinement/containment, sub-criticality, and shielding. This paper will address the importance of applying proper torque to package closures, discuss torque value nomenclature, and present one methodology to ensure torque compliance is achieved.

Watkins, R.; Leduc, D.

2011-03-24T23:59:59.000Z

14

In-line rotating capacitive torque sensor  

DOE Patents (OSTI)

A method and apparatus for measuring torques developed along a rotating mechanical assembly comprising a rotating inner portion and a stationary outer portion. The rotating portion has an electrically-conductive flexing section fitted between two coaxial shafts in a configuration which varies radially in accordance with applied torque. The stationary portion comprises a plurality of conductive plates forming a surface concentric with and having a diameter slightly larger than the diameter of the rotating portion. The capacitance between the outer, nonrotating and inner, rotting portion varies with changes in the radial configuration of the rotating portion. Signal output varies approximately linearly with torque for small torques, nonlinearly for larger torques. The sensor is preferably surrounded by a conductive shell to minimize electrical interference from external sources. 8 figs.

Kronberg, J.W.

1990-01-08T23:59:59.000Z

15

In-line rotating capacitive torque sensor  

DOE Patents (OSTI)

Disclosed are a method and apparatus for measuring torques developed along a rotating mechanical assembly comprising a rotating inner portion and a stationary outer portion. The rotating portion has an electrically-conductive flexing section fitted between two coaxial shafts in a configuration which varies radially in accordance with applied torque. The stationary portion comprises a plurality of conductive plates forming a surface concentric with and having a diameter slightly larger than the diameter of the rotating portion. The capacitance between the outer, nonrotating and inner, rotating portion varies with changes in the radial configuration of the rotating portion. Signal output varies approximately linearly with torque for small torques, nonlinearly for larger torques. The sensor is preferably surrounded by a conductive shell to minimize electrical interference from external sources. 18 figures.

Kronberg, J.W.

1991-09-10T23:59:59.000Z

16

Torque determination on DNA with magnetic tweezers  

E-Print Network (OSTI)

We deduced the torque applied on a single stretched and twisted DNA by integrating with respect to force the change in the molecule's extension as it is coiled. While consistent with previous direct measurements of the torque at high forces (F>1 pN) this method, which is simple and does not require a sophisticated set-up, allows for lower force estimates. We used this approach to deduce the effective torsional modulus of DNA, which decreases with force and to estimate the buckling torque of DNA as a function of force in various salt conditions.

Francesco Mosconi; Jean-François Allemand; David Bensimon; Vincent Croquette

2008-09-03T23:59:59.000Z

17

Accretion-Powered Stellar Winds II: Numerical Solutions for Stellar Wind Torques  

E-Print Network (OSTI)

[Abridged] In order to explain the slow rotation observed in a large fraction of accreting pre-main-sequence stars (CTTSs), we explore the role of stellar winds in torquing down the stars. For this mechanism to be effective, the stellar winds need to have relatively high outflow rates, and thus would likely be powered by the accretion process itself. Here, we use numerical magnetohydrodynamical simulations to compute detailed 2-dimensional (axisymmetric) stellar wind solutions, in order to determine the spin down torque on the star. We explore a range of parameters relevant for CTTSs, including variations in the stellar mass, radius, spin rate, surface magnetic field strength, the mass loss rate, and wind acceleration rate. We also consider both dipole and quadrupole magnetic field geometries. Our simulations indicate that the stellar wind torque is of sufficient magnitude to be important for spinning down a ``typical'' CTTS, for a mass loss rate of $\\sim 10^{-9} M_\\odot$ yr$^{-1}$. The winds are wide-angle, self-collimated flows, as expected of magnetic rotator winds with moderately fast rotation. The cases with quadrupolar field produce a much weaker torque than for a dipole with the same surface field strength, demonstrating that magnetic geometry plays a fundamental role in determining the torque. Cases with varying wind acceleration rate show much smaller variations in the torque suggesting that the details of the wind driving are less important. We use our computed results to fit a semi-analytic formula for the effective Alfv\\'en radius in the wind, as well as the torque. This allows for considerable predictive power, and is an improvement over existing approximations.

Sean Matt; Ralph E. Pudritz

2008-01-02T23:59:59.000Z

18

Torque shudder protection device and method  

DOE Patents (OSTI)

A torque shudder protection device for an induction machine includes a flux command generator for supplying a steady state flux command and a torque shudder detector for supplying a status including a negative status to indicate a lack of torque shudder and a positive status to indicate a presence of torque shudder. A flux adapter uses the steady state flux command and the status to supply a present flux command identical to the steady state flux command for a negative status and different from the steady state flux command for a positive status. A limiter can receive the present flux command, prevent the present flux command from exceeding a predetermined maximum flux command magnitude, and supply the present flux command to a field oriented controller. After determining a critical electrical excitation frequency at which a torque shudder occurs for the induction machine, a flux adjuster can monitor the electrical excitation frequency of the induction machine and adjust a flux command to prevent the monitored electrical excitation frequency from reaching the critical electrical excitation frequency. 5 figs.

King, R.D.; Doncker, R.W.A.A. De.; Szczesny, P.M.

1997-03-11T23:59:59.000Z

19

NovaTorque Inc | Open Energy Information  

Open Energy Info (EERE)

NovaTorque Inc NovaTorque Inc Jump to: navigation, search Name NovaTorque, Inc. Place Sunnyvale, California Zip 94086 Sector Efficiency Product A California-based motor company that has developed an electric motor technology that provides energy efficiency. Coordinates 32.780338°, -96.547405° 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":32.780338,"lon":-96.547405,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

20

Torque limit of PM motors for field-weakening region operation  

SciTech Connect

The invention includes a motor controller and technique for controlling a permanent magnet motor. In accordance with one aspect of the present technique, a permanent magnet motor is controlled by receiving a torque command, determining a physical torque limit based on a stator frequency, determining a theoretical torque limit based on a maximum available voltage and motor inductance ratio, and limiting the torque command to the smaller of the physical torque limit and the theoretical torque limit. Receiving the torque command may include normalizing the torque command to obtain a normalized torque command, determining the physical torque limit may include determining a normalized physical torque limit, determining a theoretical torque limit may include determining a normalized theoretical torque limit, and limiting the torque command may include limiting the normalized torque command to the smaller of the normalized physical torque limit and the normalized theoretical torque limit.

Royak, Semyon (Beachwood, OH); Harbaugh, Mark M. (Richfield, OH)

2012-02-14T23:59:59.000Z

Note: This page contains sample records for the topic "loss torque converter" 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

NovaTorque | Open Energy Information  

Open Energy Info (EERE)

NovaTorque NovaTorque Jump to: navigation, search Logo: NovaTorque Name NovaTorque Address 145 N. Wolfe Road Place Sunnyvale, California Zip 94086 Sector Efficiency Product high efficiency electric motors Year founded 2005 Number of employees 11-50 Phone number 408-737-2400 Website http://www.novatorque.com/ Coordinates 37.3766589°, -122.014231° 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":37.3766589,"lon":-122.014231,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

22

Uniform Realization of the Unit of Torque in the US  

Science Conference Proceedings (OSTI)

Uniform Realization of the Unit of Torque in the US. Summary: ... Start Date: February 1, 2008. Lead Organizational Unit: pml. ...

2012-05-30T23:59:59.000Z

23

Torque ripple in a Darrieus, vertical axis wind turbine  

DOE Green Energy (OSTI)

Interaction between a steady wind and a rotating, Darrieus, vertical axis wind turbine produces time periodic aerodynamic loads which cause time dependent torque variations, referred to as torque ripple, to occur in the mechanical link between the turbine and the electrical generator. There is concern for the effect of torque ripple upon fatigue life of drive train components and upon power quality. An analytical solution characterizing the phenomenon of torque ripple has been obtained which is based upon a Fourier expansion of the time dependent features of the problem. Numerical results for torque ripple, some experimental data, determination of acceptable levels and methods of controlling it, are presented and discussed.

Reuter, R.C. Jr.

1980-01-01T23:59:59.000Z

24

Interleaved power converter  

DOE Patents (OSTI)

A power converter architecture interleaves full bridge converters to alleviate thermal management problems in high current applications, and may, for example, double the output power capability while reducing parts count and costs. For example, one phase of a three phase inverter is shared between two transformers, which provide power to a rectifier such as a current doubler rectifier to provide two full bridge DC/DC converters with three rather than four high voltage inverter legs.

Zhu, Lizhi (Canton, MI)

2007-11-13T23:59:59.000Z

25

Universal thermochemical energy converter  

DOE Patents (OSTI)

Disclosed are methods and apparatus for a thermochemical closed cycle employing a polyatomic, chemically active working fluid for converting heat energy into useful work.

Labinov, Solomon Davidovich (Oak Ridge, TN); Sand, James R. (Oak Ridge, TN); Conklin, James C. (Knoxville, TN); VanCoevering, James (Oak Ridge, TN); Courville, George E. (Oak Ridge, TN)

2001-01-01T23:59:59.000Z

26

Converter-fed subsea motor drives  

SciTech Connect

A subsea adjustable-speed motor fed via a long cable in range of several tens of kilometers between the converter and the motor are analyzed by simulations. Due to resonance, one critical frequency range occurs where significant generation of harmonics from the inverter should be avoided. A voltage source inverter is more feasible than a current source inverter since it is easier to modify the output waveform in order to avoid resonance problems. The resistive voltage drop in the long cable reduces the air-gap torque of the motor particular at low frequencies. This causes a problem for the start-up of the motor due to stiction torque. A start-up strategy is envisaged which is a compromise between voltage boost, inverter current, and transformer core dimensions. In normal operation mode the inverter voltage is proportional to the frequency. An open speed lop is used which keeps the system stable for potential load variations. The results from a 1-MW full-scale system test are summarized.

Raad, R.O.; Raphael, H.B. [Statoil, Stavanger (Norway); Henriksen, T. [Norwegian Electric Power Research Inst., Trondheim (Norway); Hadler-Jacobsen, A. [Framo Engineering AS, Nesttun (Norway)

1996-09-01T23:59:59.000Z

27

Microminiature thermionic converters  

DOE Patents (OSTI)

Microminiature thermionic converts (MTCs) having high energy-conversion efficiencies and variable operating temperatures. Methods of manufacturing those converters using semiconductor integrated circuit fabrication and micromachine manufacturing techniques are also disclosed. The MTCs of the invention incorporate cathode to anode spacing of about 1 micron or less and use cathode and anode materials having work functions ranging from about 1 eV to about 3 eV. Existing prior art thermionic converter technology has energy conversion efficiencies ranging from 5-15%. The MTCs of the present invention have maximum efficiencies of just under 30%, and thousands of the devices can be fabricated at modest costs.

King, Donald B. (Albuquerque, NM); Sadwick, Laurence P. (Salt Lake City, UT); Wernsman, Bernard R. (Clairton, PA)

2001-09-25T23:59:59.000Z

28

Motor torque compensation of an induction electric motor by ...  

Motor torque compensation of an induction electric motor by adjusting a slip command during periods of supposed change in motor temperature United States Patent

29

Digital scale converter  

DOE Patents (OSTI)

A digital scale converter is provided for binary coded decimal (BCD) conversion. The converter may be programmed to convert a BCD value of a first scale to the equivalent value of a second scale according to a known ratio. The value to be converted is loaded into a first BCD counter and counted down to zero while a second BCD counter registers counts from zero or an offset value depending upon the conversion. Programmable rate multipliers are used to generate pulses at selected rates to the counters for the proper conversion ratio. The value present in the second counter at the time the first counter is counted to the zero count is the equivalent value of the second scale. This value may be read out and displayed on a conventional seven-segment digital display.

Upton, Richard G. (Oak Ridge, TN)

1978-01-01T23:59:59.000Z

30

STR_ConvertFormats  

Science Conference Proceedings (OSTI)

... 16. 17, True, AlngDat, dd-mmm-yy, ! Convert ... 18. 19, True, AlngDatTim, dd-mmm-yy hh:mm:ss, True, True, True, True, True, True, ! Display ...

2012-03-06T23:59:59.000Z

31

Electromagnetic torque analysis of a DFIG for wind turbines  

Science Conference Proceedings (OSTI)

Electromagnetic torque of doubly fed induction generator (DFIG) is a consequence of the rotor and stator supply. The stator voltage has a fixed amount and frequency. The rotor voltage of the DFIG as a part of a wind turbine has a variable amount and ... Keywords: DFIG, electromagnetic torque, renewable energy, wind turbine

Jurica Smajo; Dinko Vukadinovic

2008-05-01T23:59:59.000Z

32

A Systems Approach to the Torque Control of a Permanent Magnet Brushless Motor  

E-Print Network (OSTI)

Many approaches to force control have assumed the ability to command torques accurately. Concurrently, much research has been devoted to developing accurate torque actuation schemes. Often, torque sensors have been ...

Paul, Benjamin J.

1987-08-01T23:59:59.000Z

33

A Systems Approach to the Torque Control of a Permanent Magnet Brushless Motor  

Science Conference Proceedings (OSTI)

Many approaches to force control have assumed the ability to command torques accurately. Concurrently, much research has been devoted to developing accurate torque actuation schemes. Often, torque sensors have been utilized to close a feedback loop around ...

Benjamin J. Paul

1987-08-01T23:59:59.000Z

34

Vector generator scan converter  

DOE Patents (OSTI)

High printing speeds for graphics data are achieved with a laser printer by transmitting compressed graphics data from a main processor over an I/O (input/output) channel to a vector generator scan converter which reconstructs a full graphics image for input to the laser printer through a raster data input port. The vector generator scan converter includes a microprocessor with associated microcode memory containing a microcode instruction set, a working memory for storing compressed data, vector generator hardward for drawing a full graphic image from vector parameters calculated by the microprocessor, image buffer memory for storing the reconstructed graphics image and an output scanner for reading the graphics image data and inputting the data to the printer. The vector generator scan converter eliminates the bottleneck created by the I/O channel for transmitting graphics data from the main processor to the laser printer, and increases printer speed up to thirty fold.

Moore, James M. (Livermore, CA); Leighton, James F. (Livermore, CA)

1990-01-01T23:59:59.000Z

35

Vector generator scan converter  

DOE Patents (OSTI)

High printing speeds for graphics data are achieved with a laser printer by transmitting compressed graphics data from a main processor over an I/O channel to a vector generator scan converter which reconstructs a full graphics image for input to the laser printer through a raster data input port. The vector generator scan converter includes a microprocessor with associated microcode memory containing a microcode instruction set, a working memory for storing compressed data, vector generator hardware for drawing a full graphic image from vector parameters calculated by the microprocessor, image buffer memory for storing the reconstructed graphics image and an output scanner for reading the graphics image data and inputting the data to the printer. The vector generator scan converter eliminates the bottleneck created by the I/O channel for transmitting graphics data from the main processor to the laser printer, and increases printer speed up to thirty fold. 7 figs.

Moore, J.M.; Leighton, J.F.

1988-02-05T23:59:59.000Z

36

Thermionic energy converters  

DOE Patents (OSTI)

A thermionic device for converting nuclear energy into electrical energy comprising a tubular anode spaced from and surrounding a cylindrical cathode, the cathode having an outer emitting surface of ruthenium, and nuclear fuel on the inner cylindrical surface. The nuclear fuel is a ceramic composition of fissionable material in a metal matrix. An axial void is provided to collect and contain fission product gases.

Monroe, Jr., James E. (Timonium, MD)

1977-08-09T23:59:59.000Z

37

Liquid metal thermal electric converter  

DOE Patents (OSTI)

A liquid metal thermal electric converter which converts heat energy to electrical energy. The design of the liquid metal thermal electric converter incorporates a unique configuration which directs the metal fluid pressure to the outside of the tube which results in the structural loads in the tube to be compressive. A liquid metal thermal electric converter refluxing boiler with series connection of tubes and a multiple cell liquid metal thermal electric converter are also provided.

Abbin, Joseph P. (Albuquerque, NM); Andraka, Charles E. (Albuquerque, NM); Lukens, Laurance L. (Albuquerque, NM); Moreno, James B. (Albuquerque, NM)

1989-01-01T23:59:59.000Z

38

Mechanism and assessment of spin transfer torque (STT) based memory  

E-Print Network (OSTI)

When a sufficient current density passes through the MTJ, the spin-polarized current will exert a spin transfer torque to switch the magnetization of the free layer. This is the fundamental of the novel write mechanism in ...

Loh, Iong Ying

2009-01-01T23:59:59.000Z

39

Validation of Quasigeostrophic Zonal Mean Flow Responses to Torques  

Science Conference Proceedings (OSTI)

The angular momentum balance of quasigeostrophic flows is considered both for the standard and the deep formulation of quasigeostrophic theory (QT) in height coordinates, with main emphasis on the response to mountain torques. The related budget ...

Joseph Egger; Klaus-Peter Hoinka

2003-08-01T23:59:59.000Z

40

Oceanic Angular Momentum and Torques in a General Circulation Model  

Science Conference Proceedings (OSTI)

The ocean's angular momentum (M) and torques about the Polar axis are analyzed using output from the global, eddy-resolving model of Semtner and Chervin. Seasonal variability in M is dominated by the annual cycle, whose magnitude appears capable ...

Rui M. Ponte; Richard D. Rosen

1994-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "loss torque converter" 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

Production Experiences with the Cray-Enabled TORQUE Resource Manager  

SciTech Connect

High performance computing resources utilize batch systems to manage the user workload. Cray systems are uniquely different from typical clusters due to Cray s Application Level Placement Scheduler (ALPS). ALPS manages binary transfer, job launch and monitoring, and error handling. Batch systems require special support to integrate with ALPS using an XML protocol called BASIL. Previous versions of Adaptive Computing s TORQUE and Moab batch suite integrated with ALPS from within Moab, using PERL scripts to interface with BASIL. This would occasionally lead to problems when all the components would become unsynchronized. Version 4.1 of the TORQUE Resource Manager introduced new features that allow it to directly integrate with ALPS using BASIL. This paper describes production experiences at Oak Ridge National Laboratory using the new TORQUE software versions, as well as ongoing and future work to improve TORQUE.

Ezell, Matthew A [ORNL; Maxwell, Don E [ORNL; Beer, David [Adaptive Computing

2013-01-01T23:59:59.000Z

42

Cycloidal Wave Energy Converter  

SciTech Connect

This program allowed further advancing the development of a novel type of wave energy converter, a Cycloidal Wave Energy Converter or CycWEC. A CycWEC consists of one or more hydrofoils rotating around a central shaft, and operates fully submerged beneath the water surface. It operates under feedback control sensing the incoming waves, and converts wave power to shaft power directly without any intermediate power take off system. Previous research consisting of numerical simulations and two dimensional small 1:300 scale wave flume experiments had indicated wave cancellation efficiencies beyond 95%. The present work was centered on construction and testing of a 1:10 scale model and conducting two testing campaigns in a three dimensional wave basin. These experiments allowed for the first time for direct measurement of electrical power generated as well as the interaction of the CycWEC in a three dimensional environment. The Atargis team successfully conducted two testing campaigns at the Texas A&M Offshore Technology Research Center and was able to demonstrate electricity generation. In addition, three dimensional wave diffraction results show the ability to achieve wave focusing, thus increasing the amount of wave power that can be extracted beyond what was expected from earlier two dimensional investigations. Numerical results showed wave cancellation efficiencies for irregular waves to be on par with results for regular waves over a wide range of wave lengths. Using the results from previous simulations and experiments a full scale prototype was designed and its performance in a North Atlantic wave climate of average 30kW/m of wave crest was estimated. A full scale WEC with a blade span of 150m will deliver a design power of 5MW at an estimated levelized cost of energy (LCOE) in the range of 10-17 US cents per kWh. Based on the new results achieved in the 1:10 scale experiments these estimates appear conservative and the likely performance at full scale will exceed this initial performance estimates. In advancing the Technology Readiness Level (TRL) of this type of wave energy converter from 3 to 4, we find the CycWEC to exceed our initial estimates in terms of hydrodynamic performance. Once fully developed and optimized, it has the potential to not just outperform all other WEC technologies, but to also deliver power at a lower LCOE than competing conventional renewables like wind and solar. Given the large wave power resource both domestically and internationally, this technology has the potential to lead to a large improvement in our ability to produce clean electricity at affordable cost.

Stefan G. Siegel, Ph.D.

2012-11-30T23:59:59.000Z

43

DC systems with transformerless converters  

Science Conference Proceedings (OSTI)

A technical and economic feasibility study of HVDC systems without converter transformers is presented. The presentation includes proposed solutions to the drawback related to the absence of galvanic separation between the ac and dc systems, if the converter transformers are eliminated. The results show that HVDC systems without converter transformers are both technically and economically feasible. The cost savings can be substantial.

Vithayathil, J.J.; Mittlestadt, W. [Bonneville Power Administration, Portland, OR (United States); Bjoerklund, P.E. [ABB Power Systems AB, Ludvika (Sweden)

1995-07-01T23:59:59.000Z

44

Bidirectional buck boost converter  

DOE Patents (OSTI)

A bidirectional buck boost converter and method of operating the same allows regulation of power flow between first and second voltage sources in which the voltage level at each source is subject to change and power flow is independent of relative voltage levels. In one embodiment, the converter is designed for hard switching while another embodiment implements soft switching of the switching devices. In both embodiments, first and second switching devices are serially coupled between a relatively positive terminal and a relatively negative terminal of a first voltage source with third and fourth switching devices serially coupled between a relatively positive terminal and a relatively negative terminal of a second voltage source. A free-wheeling diode is coupled, respectively, in parallel opposition with respective ones of the switching devices. An inductor is coupled between a junction of the first and second switching devices and a junction of the third and fourth switching devices. Gating pulses supplied by a gating circuit selectively enable operation of the switching devices for transferring power between the voltage sources. In the second embodiment, each switching device is shunted by a capacitor and the switching devices are operated when voltage across the device is substantially zero. 20 figs.

Esser, A.A.M.

1998-03-31T23:59:59.000Z

45

Heat engine and electric motor torque distribution strategy for a hybrid electric vehicle  

DOE Patents (OSTI)

A method is provided for controlling a power train system for a hybrid electric vehicle. The method includes a torque distribution strategy for controlling the engine and the electric motor. The engine and motor commands are determined based upon the accelerator position, the battery state of charge and the amount of engine and motor torque available. The amount of torque requested for the engine is restricted by a limited rate of rise in order to reduce the emissions from the engine. The limited engine torque is supplemented by motor torque in order to meet a torque request determined based upon the accelerator position.

Boberg, Evan S. (Hazel Park, MI); Gebby, Brian P. (Hazel Park, MI)

1999-09-28T23:59:59.000Z

46

Kinetic energy principle and neoclassical toroidal torque in tokamaks  

Science Conference Proceedings (OSTI)

It is shown that when tokamaks are perturbed, the kinetic energy principle is closely related to the neoclassical toroidal torque by the action invariance of particles. Especially when tokamaks are perturbed from scalar pressure equilibria, the imaginary part of the potential energy in the kinetic energy principle is equivalent to the toroidal torque by the neoclassical toroidal viscosity. A unified description therefore should be made for both physics. It is also shown in this case that the potential energy operator can be self-adjoint and thus the stability calculation can be simplified by minimizing the potential energy.

Park, Jong-Kyu [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)

2011-11-15T23:59:59.000Z

47

Kinetic Energy Principle And Neoclassical Toroidal Torque In Tokamaks  

Science Conference Proceedings (OSTI)

It is shown that when tokamaks are perturbed the kinetic energy principle is closely related to the neoclassical toroidal torque by the action invariance of particles. Especially when tokamaks are perturbed from scalar pressure equilibria, the imaginary part of the potential energy in the kinetic energy principle is equivalent to the toroidal torque by the Neoclassical Toroidal Viscosity (NTV). A unified description therefore should be made for both physics. It is also shown in this case that the potential energy operator can be self-adjoint and thus the stability calculation can be simplified by minimizing the potential energy

Jong-Kyu Park

2011-11-07T23:59:59.000Z

48

Advanced converter reactors  

SciTech Connect

Advanced converter reactors (ACRs) of primary US interest are those which can be commercialized within about 20 years, and are: Advanced Light-Water Reactors, Spectral-Shift-Control Reactors, Heavy-Water Reactors (CANDU type), and High-Temperature Gas-Cooled Reactors. These reactors can operate on uranium, thorium, or uranium-thorium fuel cycles, but have the greatest fuel utilization on thorium type cycles. The water reactors tend to operate more economically on uranium cycles, while the HTGR is more economical on thorium cycles. Thus, the HTGR had the greatest practical potential for improving fuel utilization. If the US has 3.4 to 4 million tons U/sub 3/O/sub 8/ at reasonable costs, ACRs can make important contributions to maintaining a high nuclear power level for many decades; further, they work well with fast breeder reactors in the long term under symbiotic fueling conditions. Primary nuclear data needs of ACRs are integral measurements of reactivity coefficients and resonance absorption integrals.

Kasten, P.R.

1979-01-01T23:59:59.000Z

49

Analytical Method of Torque Calculation for Interior Permanent Magnet Synchronous Machines  

E-Print Network (OSTI)

method for performing the output torque calculations of an interior permanent magnet synchronous motor circuit, inductance, permanent magnet machine, synchronous motors, torque. I. NOMENCLATURE BFE brushless field excitation IPMSM interior permanent magnet synchronous motor FEA finite element analysis mmf

Tolbert, Leon M.

50

Please do not use the torque directive mppnppn in your job scrpts  

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

Please do not use the torque directive mppnppn in your job scrpts Please do not use the torque directive mppnppn in your job scrpts August 2, 2013 (0 Comments) As of 815 12:30...

51

Greenhouse Gases Converted to Fuel  

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

Greenhouse Greenhouse Gases Converted to Fuel Greenhouse Gases Converted to Fuel carbon-conversion-fig-1.jpg Key Challenges: An important strategy for reducing global CO2 emissions calls for capturing the greenhouse gas and converting it to fuels and chemicals. Although researchers working toward that goal demonstrated in 1992 such a reaction in the lab, a key outstanding scientific challenge was explaining the details of how the reaction took place - its "mechanism." Why it Matters: An important potential strategy for reducing global CO2 emissions calls for capturing the greenhouse gas and converting it electrochemically to fuels and chemicals. Accomplishments: Computation to explain how carbon dioxide can be converted to small organic molecules with little energy input. The

52

Doubly-fed induction generator torque in wind turbines  

Science Conference Proceedings (OSTI)

The field oriented doubly-fed induction generator (DFIG) is being increasingly used in variable speed wind turbines. It is therefore indispensable to become better acquainted with electrical and mechanical DFIG features in both stationary and dynamic ... Keywords: doubly-fed induction generator (DFIG), torque characteristic of DFIG

Jurica Smajo; Dinko Vukadinovic

2008-02-01T23:59:59.000Z

53

SVPWM-Based Simulation of Direct Torque Control in Permanent Magnet Synchronous Motor  

Science Conference Proceedings (OSTI)

On the basis of analysis of the mathematical model of permanent magnet synchronous motor (PMSM), this paper is to propose a new type direct torque control system based on space vector pulse width modulation (SVPWM) technology aiming at big torque ripple, ... Keywords: permanent magnet synchronous motor, direct torque control, space vector pulse width modulation, MATLAB/Simulink

Huang Xianghui, Sun Nan

2013-10-01T23:59:59.000Z

54

Closed-loop torque feedback for a universal field-oriented controller  

DOE Patents (OSTI)

A torque feedback system is employed in a universal field-oriented (UFO) controller to tune a torque-producing current command and a slip frequency command in order to achieve robust torque control of an induction machine even in the event of current regulator errors and during transitions between pulse width modulated (PWM) and square wave modes of operation. 1 figure.

De Doncker, R.W.A.A.; King, R.D.; Sanza, P.C.; Haefner, K.B.

1992-11-24T23:59:59.000Z

55

Closed-loop torque feedback for a universal field-oriented controller  

DOE Patents (OSTI)

A torque feedback system is employed in a universal field-oriented (UFO) controller to tune a torque-producing current command and a slip frequency command in order to achieve robust torque control of an induction machine even in the event of current regulator errors and during transitions between pulse width modulated (PWM) and square wave modes of operation.

De Doncker, Rik W. A. A. (Schenectady, NY); King, Robert D. (Schenectady, NY); Sanza, Peter C. (Clifton Park, NY); Haefner, Kenneth B. (Schenectady, NY)

1992-01-01T23:59:59.000Z

56

Cycling firing method for bypass operation of bridge converters  

DOE Patents (OSTI)

The bridge converter comprises a number of switching elements and an electronic logic system which regulated the electric power levels by controlling the firing, i.e., the initiation of the conduction period of the switching elements. Cyclic firing of said elements allows the direct current to bypass the alternating current system with high power factor and negligible losses.

Zabar, Zivan (99-72 66th Rd., Apt. 9N, Forest Hills, NY 11375)

1982-01-01T23:59:59.000Z

57

Key-and-keyway coupling for transmitting torque  

DOE Patents (OSTI)

The design of an improved key-and-keyway coupling for the transmission of torque is given. The coupling provides significant reductions in stress concentrations in the vicinity of the key and keyway. The keyway is designed with a flat-bottomed u-shaped portion whose inboard end terminates in a ramp which is dished transversely, so that the surface of the ramp as viewed in transverse section defines an outwardly concave arc.

Blue, S.C.; Curtis, M.T.; Orthwein, W.C.; Stitt, D.H.

1975-11-18T23:59:59.000Z

58

The torque-speed relationship of the bacterial flagellar motor  

E-Print Network (OSTI)

Many swimming bacteria are propelled by flagellar filaments driven by a rotary motor. Each of these tiny motors can generate an impressive torque. The motor torque vs. speed relationship is considered one of the most important measurable characteristics of the motor and therefore is a major criterion for judging models proposed for the working mechanism. Here we give an explicit explanation for this torque–speed curve. The same physics also can explain certain puzzling properties of other motors. energy conversion ? mathematical model ? molecular motor ? proton motive force ? mechanochemistry The bacterial flagellar motor (BFM) consists of a rotary motor embedded in the cell envelope connected to an extracellular helical propeller (see Fig. 1) (1–4). The motor is powered by the flow of ions down an electrochemical gradient across the cytoplasmic membrane into the cell. The ions are typically H ? (protons) in Escherichia coli and Na ? in alkalophiles and marine Vibrio species. For convenience of discussion, we will focus on the proton motor, although most of the discussion applies to the sodium motor as well. The electrochemical gradient, ?? ˜ (‘‘proton-motive force’ ’ or ‘‘sodium-motive force’’), consists of a transmembrane voltage and a concentration difference across the membrane, both of which are maintained by various metabolic processes. The proton-motive force is defined as ?? ˜ ? pmf ? ?? Ç membrane potential ? 2.303 kBT e ?pH.

Jianhua Xing; Fan Bai; Richard Berry; George Oster; Transmembrane Ion

2006-01-01T23:59:59.000Z

59

Sensorless Direct Torque Control For Salient Pole PMSM Based on Extended Kalman Filter Fed By AC/DC/AC Converter  

E-Print Network (OSTI)

, Algeria Abstract -- In this paper, a new sensorless Interior Permanent Magnet Synchronous Motor (IPMSM. Key words-- DTC; sensorless control; extended Kalman filter; Permanent Magnet Synchronous Motor; boost-rectifier. I. INTRODUCTION Permanent magnet synchronous motors (PMSMS) are widely used in many applications

Paris-Sud XI, Université de

60

Array Converter | Open Energy Information  

Open Energy Info (EERE)

Converter Converter Jump to: navigation, search Name Array Converter Place Sunnyvale, California Zip 94086 Product US manufacturer of micro-inverters. Coordinates 32.780338°, -96.547405° 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":32.780338,"lon":-96.547405,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

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61

A high-efficiency thermoelectric converter for space applications  

DOE Green Energy (OSTI)

This paper presents a concept for using high-temperature superconducting materials in thermoelectric generators (SCTE) to produce electricity at conversion efficiencies approaching 50% of the Carrot efficiency. The SCTE generator is applicable to systems operating in temperature ranges of high-temperature superconducting materials and thus would be a low-grade converter. Operating in cryogenic temperature ranges provides the advantage of inherently increasing the limits of the Carrot efficiency. Potential applications are for systems operating in space where the ambient temperatures are in the cryogenic temperature range. The advantage of using high-temperature superconducting material in a thermoelectric converter is that it would significantly reduce or eliminate the Joule heating losses in a thermoelectric element. This paper investigates the system aspects and the material requirements of the SCTE converter concept, and presents a conceptual design and an application for a space power system.

Metzger, J.D. [Westinghouse Savannah River Co., Aiken, SC (United States); El-Genk, M.S. [New Mexico Univ., Albuquerque, NM (United States). Inst. for Space Nuclear Power Studies

1990-12-31T23:59:59.000Z

62

A high-efficiency thermoelectric converter for space applications  

DOE Green Energy (OSTI)

This paper presents a concept for using high-temperature superconducting materials in thermoelectric generators (SCTE) to produce electricity at conversion efficiencies approaching 50% of the Carrot efficiency. The SCTE generator is applicable to systems operating in temperature ranges of high-temperature superconducting materials and thus would be a low-grade converter. Operating in cryogenic temperature ranges provides the advantage of inherently increasing the limits of the Carrot efficiency. Potential applications are for systems operating in space where the ambient temperatures are in the cryogenic temperature range. The advantage of using high-temperature superconducting material in a thermoelectric converter is that it would significantly reduce or eliminate the Joule heating losses in a thermoelectric element. This paper investigates the system aspects and the material requirements of the SCTE converter concept, and presents a conceptual design and an application for a space power system.

Metzger, J.D. (Westinghouse Savannah River Co., Aiken, SC (United States)); El-Genk, M.S. (New Mexico Univ., Albuquerque, NM (United States). Inst. for Space Nuclear Power Studies)

1990-01-01T23:59:59.000Z

63

Multilevel converters for power system applications  

SciTech Connect

Multilevel converters are emerging as a new breed of power converter options for power system applications. These converters are most suitable for high voltage high power applications because they connect devices in series without the need for component matching. One of the major limitations of the multilevel converters is the voltage unbalance between different levels. To avoid voltage unbalance between different levels, several techniques have been proposed for different applications. Excluding magnetic-coupled converters, this paper introduces three multilevel voltage source converters: (1) diode-clamp, (2) flying-capacitors, and (3) cascaded inverters with separate dc sources. The operation principle, features, constraints, and potential applications of these converters will be discussed.

Lai, J.S.; Stovall, J.P. [Oak Ridge National Lab., TN (United States); Peng, F.Z. [Univ. of Tennessee, Knoxville, TN (United States)]|[Oak Ridge National Lab., TN (United States)

1995-09-01T23:59:59.000Z

64

Use of MCC-Based Motor Torque Measurements for Periodic Verification of Motor-Operated Valves  

Science Conference Proceedings (OSTI)

This report develops, justifies, and validates a motor control center- (MCC-) based motor torque periodic verification (MTPV) method for torque-switch-controlled closing strokes of rising stem motor-operated valves (MOVs) with ac motors. The report details the evaluation of motor torque data obtained from electrical measurements at the MCC and covers the use of these (and other) measurements in MOV periodic verification (PV) testing.

2006-03-30T23:59:59.000Z

65

Instantaneous engine frictional torque, its components and piston assembly friction  

DOE Green Energy (OSTI)

The overall goal of this report is to document the work done to determine the instantaneous frictional torque of internal combustion engine by using a new approach known as (P-[omega]) method developed at Wayne State University. The emphasis has been to improve the accuracy of the method, and apply it to both diesel and gasoline engines under different operating conditions. Also work included an investigation to determine the effect of using advanced materials and techniques to coat the piston rings on the instantaneous engine frictional torque and the piston assembly friction. The errors in measuring the angular velocity, [omega], have been determined and found to be caused by variations in the divisions within one encoder, encoder-to-encoder variations, misalignment within the encoder itself and misalignment between the encoder and crankshaft. The errors in measuring the cylinder gas pressure, P, have been determined and found to be caused by transducer-to-transducer variations, zero drift, thermal stresses and lack of linearity. The ability of the (P-[omega]) method in determining the frictional torque of many engine components has been demonstrated. These components include valve train, fuel injection pump with and without fuel injection, and piston with and without different ring combinations. The emphasis in this part of the research program has been on the piston-ring assembly friction. The effects of load and other operating variables on IFT have been determined. The motoring test, which is widely used in industry to measure engine friction has been found to be inaccurate. The errors have been determined at different loads.

Nichols, F.A. (ed.) (Argonne National Lab., IL (United States)); Henein, N.A. (Wayne State Univ., Detroit, MI (United States). Center for Automotive Research)

1992-05-01T23:59:59.000Z

66

Universal adaptive torque control for PM motors for field-weakening region operation  

Science Conference Proceedings (OSTI)

The invention includes a motor controller and method for controlling a permanent magnet motor. In accordance with one aspect of the present technique, a permanent magnet motor is controlled by, among other things, receiving a torque command, determining a normalized torque command by normalizing the torque command to a characteristic current of the motor, determining a normalized maximum available voltage, determining an inductance ratio of the motor, and determining a direct-axis current based upon the normalized torque command, the normalized maximum available voltage, and the inductance ratio of the motor.

Royak, Semyon (Beachwood, OH); Harbaugh, Mark M. (Richfield, OH); Breitzmann, Robert J. (South Russel, OH); Nondahl, Thomas A. (Wauwatosa, WI); Schmidt, Peter B. (Franklin, WI); Liu, Jingbo (Milwaukee, WI)

2011-03-29T23:59:59.000Z

67

Experimental Analysis of the Flow, Pressure, Speed, and Torque Characteristics of Two Eaton Geroler Hydraulic Motors.  

E-Print Network (OSTI)

??This paper presents data collected examining the flow, pressure, speed, and torque characteristics of two Eaton Geroler hydraulic motors. A test installation was designed and… (more)

Cazaban, Philip M.

2011-01-01T23:59:59.000Z

68

Portable convertible blast effects shield  

DOE Patents (OSTI)

A rapidly deployable portable convertible blast effects shield/ballistic shield includes a set two or more telescoping cylindrical rings operably connected to each other to convert between a telescopically-collapsed configuration for storage and transport, and a telescopically-extended upright configuration forming an expanded inner volume. In a first embodiment, the upright configuration provides blast effects shielding, such as against blast pressures, shrapnel, and/or fire balls. And in a second embodiment, the upright configuration provides ballistic shielding, such as against incoming weapons fire, shrapnel, etc. Each ring has a high-strength material construction, such as a composite fiber and matrix material, capable of substantially inhibiting blast effects and impinging projectiles from passing through the shield. And the set of rings are releasably securable to each other in the telescopically-extended upright configuration, such as by click locks.

Pastrnak, John W. (Livermore, CA); Hollaway, Rocky (Modesto, CA); Henning, Carl D. (Livermore, CA); Deteresa, Steve (Livermore, CA); Grundler, Walter (Hayward, CA); Hagler, Lisle B. (Berkeley, CA); Kokko, Edwin (Dublin, CA); Switzer, Vernon A (Livermore, CA)

2007-05-22T23:59:59.000Z

69

Portable convertible blast effects shield  

DOE Patents (OSTI)

A rapidly deployable portable convertible blast effects shield/ballistic shield includes a set two or more telescoping cylindrical rings operably connected to each other to convert between a telescopically-collapsed configuration for storage and transport, and a telescopically-extended upright configuration forming an expanded inner volume. In a first embodiment, the upright configuration provides blast effects shielding, such as against blast pressures, shrapnel, and/or fire balls. And in a second embodiment, the upright configuration provides ballistic shielding, such as against incoming weapons fire, shrapnel, etc. Each ring has a high-strength material construction, such as a composite fiber and matrix material, capable of substantially inhibiting blast effects and impinging projectiles from passing through the shield. And the set of rings are releasably securable to each other in the telescopically-extended upright configuration, such as by click locks.

Pastrnak, John W. (Livermore, CA); Hollaway, Rocky (Modesto, CA); Henning, Carl D. (Livermore, CA); Deteresa, Steve (Livermore, CA); Grundler, Walter (Hayward, CA); Hagler,; Lisle B. (Berkeley, CA); Kokko, Edwin (Dublin, CA); Switzer, Vernon A (Livermore, CA)

2010-10-26T23:59:59.000Z

70

Portable convertible blast effects shield  

DOE Patents (OSTI)

A rapidly deployable portable convertible blast effects shield/ballistic shield includes a set two or more frusto-conically-tapered telescoping rings operably connected to each other to convert between a telescopically-collapsed configuration for storage and transport, and a telescopically-extended upright configuration forming an expanded inner volume. In a first embodiment, the upright configuration provides blast effects shielding, such as against blast pressures, shrapnel, and/or fire balls. And in a second embodiment, the upright configuration provides ballistic shielding, such as against incoming weapons fire, shrapnel, etc. Each ring has a high-strength material construction, such as a composite fiber and matrix material, capable of substantially inhibiting blast effects and impinging projectiles from passing through the shield. And the set of rings are releasably securable to each other in the telescopically-extended upright configuration by the friction fit of adjacent pairs of frusto-conically-tapered rings to each other.

Pastrnak, John W. (Livermore, CA); Hollaway, Rocky (Modesto, CA); Henning, Carl D. (Livermore, CA); Deteresa, Steve (Livermore, CA); Grundler, Walter (Hayward, CA); Hagler, Lisle B. (Berkeley, CA); Kokko, Edwin (Dublin, CA); Switzer, Vernon A. (Livermore, CA)

2011-03-15T23:59:59.000Z

71

Converting Petroleum Coke to Electricity  

E-Print Network (OSTI)

Changes in oil refining technology and economics are driving refiners to utilize thermal processes to maximize the conversion of heavy crude oil components to clean products. Since the primary unit operation to accomplish this objective is the coking unit, more cokers are being built, and existing cokers are being operated to maximum capacity utilization. SRI recently completed an assignment for a refiner interested in converting the by-product fluid coke from his unit to electricity. This paper presents the operating history of US based plants converting petroleum coke to electricity, and presents generic economics for the conversion process utilizing three primary technologies available: conventional pulverized coke combustion, atmospheric fluidized bed combustion, and coke gasification combined cycle power production.

Pavone, A.

1992-04-01T23:59:59.000Z

72

Neuro-fuzzy modeling tools for estimation of torque in Savonius rotor wind turbine  

Science Conference Proceedings (OSTI)

In the present paper, the ability and accuracy of an adaptive neuro-fuzzy inference system (ANFIS) has been investigated for dynamic modeling of wind turbine Savonius rotor. The main objective of this research is to predict torque performance as a function ... Keywords: ANFIS, ANN, BP, FIS, LSE, MSE, Max, Min, Modeling, Prob, Prod, RBF, RMSE, SD, Savonius rotor, Torque

J. Sargolzaei; A. Kianifar

2010-04-01T23:59:59.000Z

73

Direct Torque Control for Interior Permanent Magnet Synchronous Motors with Respect to Optimal Efficiency  

E-Print Network (OSTI)

Direct Torque Control for Interior Permanent Magnet Synchronous Motors with Respect to Optimal@lea.upb.de, boecker@lea.upb.de URL: http://wwwlea.upb.de Keywords «Interior permanent magnet synchronous motor to their high torque and power per volume ratio, interior permanent magnet synchronous motors (IPMSM

Noé, Reinhold

74

Pulsating Torque Reduction for Permanent Magnet Bojan Grcar, Peter Cafuta, Gorazd Stumberger  

E-Print Network (OSTI)

Pulsating Torque Reduction for Permanent Magnet AC Motors Bojan Grcar, Peter Cafuta, Gorazd on the motor design (skewing, shifting the magnet position, special windings, etc.) [5], [6] are in general,MA Abstract-- Control methods for pulsation of torque reduction for the surface-mounted permanent magnet

Stankoviæ, Aleksandar

75

A Precise Open-Loop Torque Control for an Interior Permanent Magnet Synchronous Motor  

E-Print Network (OSTI)

A Precise Open-Loop Torque Control for an Interior Permanent Magnet Synchronous Motor (IPMSM@lea.upb.de Abstract-Interior permanent magnet synchronous motors (IPMSM) are preferentially chosen as traction drives. INTRODUCTION Interior permanent magnet synchronous motors (IPMSM) provide high power and torque densities

Noé, Reinhold

76

Application of Ant Colony Algorithm in PID Parameter Optimization for Mining Hoist Direct Torque Control System  

Science Conference Proceedings (OSTI)

The mining hoist is a key transport equipment to transfer the workers and coal between the mining well and the ground. In the traditional mining hoist direct torque control system, there are some disadvantages such as torque pulsation in the low speed ...

Xian-Min Ma

2009-01-01T23:59:59.000Z

77

Auxiliary resonant DC tank converter  

SciTech Connect

An auxiliary resonant dc tank (ARDCT) converter is provided for achieving soft-switching in a power converter. An ARDCT circuit is coupled directly across a dc bus to the inverter to generate a resonant dc bus voltage, including upper and lower resonant capacitors connected in series as a resonant leg, first and second dc tank capacitors connected in series as a tank leg, and an auxiliary resonant circuit comprising a series combination of a resonant inductor and a pair of auxiliary switching devices. The ARDCT circuit further includes first clamping means for holding the resonant dc bus voltage to the dc tank voltage of the tank leg, and second clamping means for clamping the resonant dc bus voltage to zero during a resonant period. The ARDCT circuit resonantly brings the dc bus voltage to zero in order to provide a zero-voltage switching opportunity for the inverter, then quickly rebounds the dc bus voltage back to the dc tank voltage after the inverter changes state. The auxiliary switching devices are turned on and off under zero-current conditions. The ARDCT circuit only absorbs ripples of the inverter dc bus current, thus having less current stress. In addition, since the ARDCT circuit is coupled in parallel with the dc power supply and the inverter for merely assisting soft-switching of the inverter without participating in real dc power transmission and power conversion, malfunction and failure of the tank circuit will not affect the functional operation of the inverter; thus a highly reliable converter system is expected.

Peng, Fang Z. (Knoxville, TN)

2000-01-01T23:59:59.000Z

78

Converting Energy to Medical Progress  

Office of Scientific and Technical Information (OSTI)

Converting Converting to April 2001 An introduction to the unique research funded by the Medical Sciences Division Biological and Environmental Research (BER) Office of Science, U.S. Department of Energy Nuclear Medicine E v e r y w h e r e i n He a l t h c a r e A n d s o do e s B E R N u c l e a r M e d i c i n e H e lps P a t i e n t s the Office of Biological and Environmental Research (BER) of the United States Department of Energy (DOE) has been investing to advance environmental and biomedical knowledge connected to energy. The BER Medical Sciences program fosters research to develop beneficial applications of nuclear technologies for medical diagnosis and treatment of many diseases. Today, nuclear medicine helps millions of patients annually in the United States. Nearly every nuclear medicine scan or test used today was made possible by

79

Converting Energy to Medical Progress  

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

Converting Converting to April 2001 An introduction to the unique research funded by the Medical Sciences Division Biological and Environmental Research (BER) Office of Science, U.S. Department of Energy Nuclear Medicine E v e r y w h e r e i n He a l t h c a r e A n d s o do e s B E R N u c l e a r M e d i c i n e H e lps P a t i e n t s the Office of Biological and Environmental Research (BER) of the United States Department of Energy (DOE) has been investing to advance environmental and biomedical knowledge connected to energy. The BER Medical Sciences program fosters research to develop beneficial applications of nuclear technologies for medical diagnosis and treatment of many diseases. Today, nuclear medicine helps millions of patients annually in the United States. Nearly every nuclear medicine scan or test used today was made possible by

80

An Analytical Equation for Cogging Torque Calculation in Permanent Magnet Motors Lu, Kaiyuan; Rasmussen, Peter Omand; Ritchie, Andrew Ewen  

E-Print Network (OSTI)

An Analytical Equation for Cogging Torque Calculation in Permanent Magnet Motors Lu, Kaiyuan Torque Calculation in Permanent Magnet Motors. Paper presented at 17th International Conference to the prediction of the cogging torque in motors with parallel or radial magnetized permanent magnets. The magnetic

Rasmussen, Peter Omand

Note: This page contains sample records for the topic "loss torque converter" 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
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81

Direct torque control of permanent magnet synchronous motors with non-sinusoidal back-EMF  

E-Print Network (OSTI)

This work presents the direct torque control (DTC) techniques, implemented in four- and six-switch inverter, for brushless dc (BLDC) motors with non-sinusoidal back- EMF using two and three-phase conduction modes. First of all, the classical direct torque control of permanent magnet synchronous motor (PMSM) with sinusoidal back-EMF is discussed in detail. Secondly, the proposed two-phase conduction mode for DTC of BLDC motors is introduced in the constant torque region. In this control scheme, only two phases conduct at any instant of time using a six-switch inverter. By properly selecting the inverter voltage space vectors of the two-phase conduction mode from a simple look-up table the desired quasi-square wave current is obtained. Therefore, it is possible to achieve DTC of a BLDC motor drive with faster torque response while the stator flux linkage amplitude is deliberately kept almost constant by ignoring the flux control in the constant torque region. Third, the avarege current controlled boost power factor correction (PFC) method is applied to the previously discussed proposed DTC of BLDC motor drive in the constant torque region. The test results verify that the proposed PFC for DTC of BLDC motor drive improves the power factor from 0.77 to about 0.9997 irrespective of the load. Fourth, the DTC technique for BLDC motor using four-switch inverter in the constant torque region is studied. For effective torque control in two phase conduction mode, a novel switching pattern incorporating the voltage vector look-up table is designed and implemented for four-switch inverter to produce the desired torque characteristics. As a result, it is possible to achieve two-phase conduction DTC of a BLDC motor drive using four-switch inverter with faster torque response due to the fact that the voltage space vectors are directly controlled.. Finally, the position sensorless direct torque and indirect flux control (DTIFC) of BLDC motor with non-sinusoidal back-EMF has been extensively investigated using three-phase conduction scheme with six-switch inverter. In this work, a novel and simple approach to achieve a low-frequency torque ripple-free direct torque control with maximum efficiency based on dq reference frame similar to permanent magnet synchronous motor (PMSM) drives is presented.

Ozturk, Salih Baris

2008-05-01T23:59:59.000Z

82

A Dual Supply Buck Converter with Improved Light Load Efficiency  

E-Print Network (OSTI)

Power consumption is the primary concern in battery-operated portable applications. Buck converters have gained popularity in powering portable devices due to their compact size, good current delivery capability and high efficiency. However, portable devices are operating under light load condition for the most of the time. Conventional buck converters suffer from low light-load efficiency which severely limits battery lifetime. In this project, a novel technique for buck converter is proposed to reduce the switching loss by reducing the effective input supply voltage at light load. This is achieved by switching between two different input voltages (3.3V and 1.65V) depending on the output current value. Experimental results show that this technique improves the efficiency at light loads by 18.07%. The buck voltage possesses an output voltage of 0.9V and provides a maximum output current of 400mA. The buck converter operates at a switching frequency of 1MHz. The prototype was fabricated using 0.18µm CMOS technology, and occupies a total active area of 0.6039mm^2.

Chen, Hui

2013-05-01T23:59:59.000Z

83

Thermionic converter emitter support arrangement  

DOE Green Energy (OSTI)

This document discusses a support provided for use in a thermionic converter to support an end of an emitter to keep it out of contact with a surrounding collector while allowing the emitter end to move axially as its temperature changes. The emitter end is supported by a spring structure that includes a pair of Belleville springs, and the spring structure is supported by a support structure fixed to the housing that includes the collector. The support structure is in the form of a sandwich with a small metal spring-engaging element at the front end, a larger metal main support at the rear end that is attached to the housing, and with a ceramic layer between them that is bonded by hot isostatic pressing to the metal element and metal main support. The spring structure can include a loose wafer captured between the Belleville springs. 7 figs.

Allen, D.T.

1989-07-06T23:59:59.000Z

84

Investigations of the torque anomaly in an annular sector. II. Global calculations, electromagnetic case  

E-Print Network (OSTI)

Recently, it was suggested that there was some sort of breakdown of quantum field theory in the presence of boundaries, manifesting itself as a torque anomaly. In particular, Fulling et al. used the finite energy-momentum-stress tensor in the presence of a perfectly conducting wedge, calculated many years ago by Deutsch and Candelas, to compute the torque on one of the wedge boundaries, where the latter was cutoff by integrating the torque density down to minimum lower radius greater than zero. They observed that that torque is not equal to the negative derivative of the energy obtained by integrating the energy density down to the same minimum radius. This motivated a calculation of the torque and energy in an annular sector obtained by the intersection of the wedge with two coaxial cylinders. In a previous paper we showed that for the analogous scalar case, which also exhibited a torque anomaly in the absence of the cylindrical boundaries, the point-split regulated torque and energy indeed exhibit an anomaly, unless the point-splitting is along the axis direction. In any case, because of curvature divergences, no unambiguous finite part can be extracted. However, that ambiguity is linear in the wedge angle; if the condition is imposed that the linear term be removed, the resulting torque and energy is finite, and exhibits no anomaly. In this paper, we demonstrate the same phenomenon takes place for the electromagnetic field, so there is no torque anomaly present here either. This is a nontrivial generalization, since the anomaly found by Fulling et al. is linear for the Dirichlet scalar case, but nonlinear for the conducting electromagnetic case.

Kimball A. Milton; Prachi Parashar; E. K. Abalo; Fardin Kheirandish; Klaus Kirsten

2013-07-09T23:59:59.000Z

85

High Power Converters for Efficient Transmission Solutions  

Science Conference Proceedings (OSTI)

... Single Valve Double Valve Quadruple Valve ... Includes 14 x 250 MVA 1-phase converter ... Serves 80 x 5 MW offshore wind turbine generators ...

2013-03-01T23:59:59.000Z

86

Energy Converting Article and Method of Making  

A graded composite having a first energy-converting surface layer of carbon bonded carbon fiber (CBCF) for absorbing light, RF, microwaves, ...

87

Converting Unconditioned Basement to Conditioned Space - Code...  

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

Conditioned Space - Code Notes Converting a basement to conditioned space increases the living space of a house. As with most construction activities, the conversion or...

88

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

89

Influence of Rain-Rate Initialization, Cloud Microphysics, and Cloud Torques on Hurricane Intensity  

Science Conference Proceedings (OSTI)

This study examines the impact of rain-rate initialization (RINIT), microphysical modifications, and cloud torques (in the context of angular momentum) on hurricane intensity forecasts using a mesoscale model [the Advanced Research Weather ...

S. Pattnaik; C. Inglish; T. N. Krishnamurti

2011-02-01T23:59:59.000Z

90

The effect of moist convection on the tropospheric response to tropical and subtropical zonally asymmetric torques  

Science Conference Proceedings (OSTI)

Tropospheric winds can be altered by vertical transfers of momentum due to orographic gravity waves and convection. Previous work showed that, in dry models, such zonally asymmetric torques produce a pattern of tropical ascent that is well-...

William R. Boos; Tiffany A. Shaw

91

Concentric ring flywheel with hooked ring carbon fiber separator/torque coupler  

DOE Patents (OSTI)

A concentric ring flywheel with expandable separators, which function as torque couplers, between the rings to take up the gap formed between adjacent rings due to differential expansion between different radius rings during rotation of the flywheel. The expandable separators or torque couplers include a hook-like section at an upper end which is positioned over an inner ring and a shelf-like or flange section at a lower end onto which the next adjacent outer ring is positioned. As the concentric rings are rotated the gap formed by the differential expansion there between is partially taken up by the expandable separators or torque couplers to maintain torque and centering attachment of the concentric rings.

Kuklo, Thomas C. (Oakdale, CA)

1999-01-01T23:59:59.000Z

92

Concentric ring flywheel with hooked ring carbon fiber separator/torque coupler  

DOE Patents (OSTI)

A concentric ring flywheel with expandable separators, which function as torque couplers, between the rings to take up the gap formed between adjacent rings due to differential expansion between different radius rings during rotation of the flywheel. The expandable separators or torque couplers include a hook-like section at an upper end which is positioned over an inner ring and a shelf-like or flange section at a lower end onto which the next adjacent outer ring is positioned. As the concentric rings are rotated the gap formed by the differential expansion there between is partially taken up by the expandable separators or torque couplers to maintain torque and centering attachment of the concentric rings. 2 figs.

Kuklo, T.C.

1999-07-20T23:59:59.000Z

93

Electromagnetic analysis of forces and torques on the ITER shield modules due to plasma disruption.  

SciTech Connect

An electromagnetic analysis is performed on the ITER shield modules under different plasma disruption scenarios using the OPERA-3d software. The modeling procedure is explained, electromagnetic torques are presented, and results of the modeling are discussed.

Kotulski, Joseph Daniel; Coats, Rebecca Sue; Pasik, Michael Francis; Ulrickson, Michael Andrew

2009-06-01T23:59:59.000Z

94

Design of a low-mass high-torque brushless motor for application in quadruped robotics  

E-Print Network (OSTI)

The Biomimetic Robotics Group is attempting to build the fastest quadruped robot powered by electromagnetic means. The limitations in achieving this goal are the torque produced from motors used to power the robot, as well ...

Farve, Niaja Nichole

2012-01-01T23:59:59.000Z

95

Vacuum-insulated catalytic converter  

DOE Patents (OSTI)

A catalytic converter has an inner canister that contains catalyst-coated substrates and an outer canister that encloses an annular, variable vacuum insulation chamber surrounding the inner canister. An annular tank containing phase-change material for heat storage and release is positioned in the variable vacuum insulation chamber a distance spaced part from the inner canister. A reversible hydrogen getter in the variable vacuum insulation chamber, preferably on a surface of the heat storage tank, releases hydrogen into the variable vacuum insulation chamber to conduct heat when the phase-change material is hot and absorbs the hydrogen to limit heat transfer to radiation when the phase-change material is cool. A porous zeolite trap in the inner canister absorbs and retains hydrocarbons from the exhaust gases when the catalyst-coated substrates and zeolite trap are cold and releases the hydrocarbons for reaction on the catalyst-coated substrate when the zeolite trap and catalyst-coated substrate get hot.

Benson, David K. (Golden, CO)

2001-01-01T23:59:59.000Z

96

Generator loss of field; Experience and studies for AEP's Rockport Plant  

SciTech Connect

This paper describes the performance of American Electric Power (AEP) Company's remotely-located 2600 MW Rockport Plant after loss of field (LOF) disturbances to one of its 1300 MW cross-compound units. Loss of field conditions occur rarely, but the resultant high currents and pulsating torques can damage a turbine-generator, and the electrical system near the disturbance will be impacted by abnormal levels or cyclic swings of power, VArs, and voltages. Rockport LOF computer simulations were conducted with recently developed detailed models; the level of detail was suggested by analyses of recent LOF experience at AEP and by recent developments in generator and excitation system modeling. Simulation results are presented to illustrate the torques, current levels, voltages, speeds, and potential relay actions following loss of field.

Rana, R.D.; Schulz, R.P. (Bulk Transmission Planning Div., American Electric Power Service Corp., Columbus, OH (US))

1989-01-01T23:59:59.000Z

97

Method and apparatus for monitoring motor operated valve motor output torque and power at valve seating  

DOE Patents (OSTI)

A method and apparatus are provided for monitoring a motor operated valve during the brief period when the valve seats and the torque switch trips to deenergize the valve motor. The method uses voltage measurements on the load side of a deenergizing switch that opens to deenergize the motor to determine, among other things, final motor rotational speed and the decelerating torque at motor deenergization.

Casada, Donald A. (Oak Ridge, TN)

1996-01-01T23:59:59.000Z

98

Method and apparatus for monitoring motor operated valve motor output torque and power at valve seating  

DOE Patents (OSTI)

A method and apparatus are provided for monitoring a motor operated valve during the brief period when the valve seats and the torque switch trips to deenergize the valve motor. The method uses voltage measurements on the load side of a deenergizing switch that opens to deenergize the motor to determine, among other things, final motor rotational speed and the decelerating torque at motor deenergization. 14 figs.

Casada, D.A.

1996-01-16T23:59:59.000Z

99

How to reduce torque and drag with a plastic sphere lubricant  

SciTech Connect

A new mud lubricant, Lubra-Beads has been used to reduce torque and drag in deviated holes, improve wire line operations, improve casing running times and, in some cases, improve rates of penetrations. Treatments have varied from batch treatments to treating the entire system. The type of treatment used depends on the problem encountered. The case histories presented described ways in which Lubra-Beads mud lubricant has been used to reduce torque and drag and increase penentration rates.

Vieaux, G.J.

1980-10-01T23:59:59.000Z

100

Measurements of Drag Torque and Lift Off Speed and Identification of Stiffness and Damping in a Metal Mesh Foil Bearing  

E-Print Network (OSTI)

Metal mesh foil bearings (MMFBs) are a promising low cost gas bearing technology for support of high speed oil-free microturbomachinery. Elimination of complex oil lubrication and sealing system by installing MMFBs in oil free rotating machinery offer distinctive advantages such as reduced system overall weight, enhanced reliability at high rotational speeds and extreme temperatures, and extended maintenance intervals compared to conventional turbo machines. MMFBs for oil-free turbomachinery must demonstrate adequate load capacity, reliable rotordynamic performance, and low frictional losses in a high temperature environment. The thesis presents the measurements of MMFB break-away torque, rotor lift off and touchdown speeds, temperature at increasing static load conditions, and identified stiffness and equivalent viscous damping coefficients. The experiments, conducted in a test rig driven by an automotive turbocharger turbine, demonstrate the airborne operation (hydrodynamic gas film) of the floating test MMFB with little frictional loses at increasing loads. The measured drag torque peaks when the rotor starts and stops, and drops significantly once the bearing is airborne. The estimated rotor speed for lift-off increases linearly with increasing applied loads. During continuous operation, the MMFB temperature measured at one end of the back surface of the top foil increases both with rotor speed and static load. Nonetheless, the temperature rise is only nominal ensuring reliable bearing performance. Application of a sacrificial layer of solid lubricant on the top foil surface aids to reduce the rotor break-away torque. The measurements give confidence on this simple bearing technology for ready application into oil-free turbomachinery. Impact loads delivered (with a soft tip) to the test bearing, while resting on the (stationary) drive shaft, evidence a system with large damping and a structural stiffness that increases with frequency (max. 200 Hz). The system equivalent viscous damping ratio decreases from ~ 0.7 to 0.2 as the frequency increases. In general, the viscous damping in a metal mesh structure is of structural type and inversely proportional to the frequency and amplitude of bearing motion relative to the shaft. Impact load tests, conducted while the shaft rotates at 50 krpm, show that the bearing direct stiffness is lower (~25% at 200 Hz) than the bearing structural stiffness identified from impact load tests without shaft rotation. However, the identified equivalent viscous damping coefficients from tests with and without shaft rotation are nearly identical. The orbits of bearing motion relative to the rotating shaft show subsynchronous motion amplitudes and also backward synchronous whirl. The subsynchronous vibration amplitudes are locked at a frequency, nearly identical to a rotor natural frequency. A backward synchronous whirl occurs while the rotor speed is between any two natural frequencies, arising due to bearing stiffness asymmetry.

Chirathadam, Thomas A.

2009-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "loss torque converter" 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

Frequency converter development for the National Ignition Facility  

SciTech Connect

The design of the National Ignition Facility (NIF) incorporates a type I/type II third harmonic generator to convert the 1.053-{micro}m fundamental wavelength of the laser amplifier to a wavelength of 0.351 {micro}m for target irradiation. To understand and control the tolerances in the converter design, we have developed a comprehensive error budget that accounts for effects that are known to influence conversion efficiency, including variations in amplitude and phase of the incident laser pulse, temporal bandwidth of the incident laser pulse, crystal surface figure and bulk non-uniformities, angular alignment errors, Fresnel losses, polarization errors and crystal temperature variations. The error budget provides specifications for the detailed design of the NIF final optics assembly (FOA) and the fabrication of optical components. Validation is accomplished through both modeling and measurement, including full-scale Beamlet tests of a 37-cm aperture frequency converter in a NIF prototype final optics cell. The prototype cell incorporates full-perimeter clamping to support the crystals, and resides in a vacuum environment as per the NIF design.

Auerbach, J M; Barker, C E; Burkhart, S C; Couture, S A; DeYoreo, J J; Hackel, L A; Hibbard, R L; Liou, L W; Norton, M A; Wegner, P J; Whitman, P A

1998-10-30T23:59:59.000Z

102

Automated Synthesis Tool for Design Optimization of Power Electronic Converters  

E-Print Network (OSTI)

Designers of power electronic converters usually face the challenge of having multiple performance indices that must be simultaneously optimized, such as maximizing efficiency while minimizing mass or maximizing reliability while minimizing cost. The experienced engineer applies his or her judgment to reduce the number of possible designs to a manageable number of feasible designs for which to prototype and test; thus, the optimality of this design-space reduction is directly dependent upon the experience, and expertise and biases of the designer. The practitioner is familiar with tradeoff analysis; however, simple tradeoff studies can become difficult or even intractable if multiple metrics are considered. Hence a scientific and systematic approach is needed. In this dissertation, a multi-objective optimization framework is presented as a design tool. Optimization of power electronic converters is certainly not a new subject. However, when limited to off-the-shelf components, the resulting system is really optimized only over the set of commercially available components, which may represent only a subset of the design space; the reachable space limited by available components and technologies. While this approach is suited to cost-reduce an existing design, it offers little insight into design possibilities for greenfield projects. Instead, this work uses the Technology Characterization Methods (TCM) to broaden the reachable design space by considering fundamental component attributes. The result is the specification for the components that create the optimal design rather than an evaluation of an apriori selected set of candidate components. A unique outcome of this approach is that new technology development vectors may emerge to develop optimized components for the optimized power converter. The approach presented in this work uses a mathematical descriptive language to abstract the characteristics and attributes of the components used in a power electronic converter in a way suitable for multi-objective and constrained optimization methods. This dissertation will use Technology Characterization Methods (TCM) to bridge the gap between high-level performance attributes and low-level design attributes where direct relationship between these two does not currently exist. The loss and size models for inductors, capacitors, IGBTs, MOSFETs and heat sinks will be used to form objective functions for the multi-objective optimization problem. A single phase IGBT-based inverter is optimized for efficiency and volume based on the component models derived using TCM. Comparing the obtained designs to a design, which can be made from commercial off-the-shelf components, shows that converter design can be optimized beyond what is possible from using only off-the-shelf components. A module-integrated photovoltaic inverter is also optimized for efficiency, volume and reliability. An actual converter is constructed using commercial off-the-shelf components. The converter design is chosen as close as possible to a point obtained by optimization. Experimental results show that the converter modeling is accurate. A new approach for evaluation of efficiency in photovoltaic converter is also proposed and the front-end portion of a photovoltaic converter is optimized for this efficiency, as well as reliability and volume.

Mirjafari, Mehran

2013-05-01T23:59:59.000Z

103

A Low-Cost Soft-Switched DC/DC Converter for Solid-Oxide Fuel Cells  

DOE Green Energy (OSTI)

A highly efficient DC to DC converter has been developed for low-voltage high-current solid oxide fuel cells. The newly developed 'V6' converter resembles what has been done in internal combustion engine that split into multiple cylinders to increase the output capacity without having to increase individual cell size and to smooth out the torque with interleaving operation. The development was started with topology overview to ensure that all the DC to DC converter circuits were included in the study. Efficiency models for different circuit topologies were established, and computer simulations were performed to determine the best candidate converter circuit. Through design optimization including topology selection, device selection, magnetic component design, thermal design, and digital controller design, a bench prototype rated 5-kW, with 20 to 50V input and 200/400V output was fabricated and tested. Efficiency goal of 97% was proven achievable through hardware experiment. This DC to DC converter was then modified in the later stage to converter 35 to 63 V input and 13.8 V output for automotive charging applications. The complete prototype was tested at Delphi with their solid oxide fuel cell test stand to verify the performance of the modified DC to DC converter. The output was tested up to 3-kW level, and the efficiency exceeded 97.5%. Multiple-phase interleaving operation design was proved to be reliable and ripple free at the output, which is desirable for the battery charging. Overall this is a very successful collaboration project between the SECA Core Technology Team and Industrial Team.

Jason Lai

2009-03-03T23:59:59.000Z

104

Regenerative Braking for an Electric Vehicle Using Ultracapacitors and a Buck-Boost Converter  

E-Print Network (OSTI)

-mail: jdixon@ing.puc.cl *University of Concepción Abstract An ultracapacitor bank control system and decelerations of the vehicle with minimal loss of energy, and minimal degradation of the main battery pack. The system uses an IGBT Buck-Boost converter, which is connected to the ultracapacitor bank at the Boost side

Rudnick, Hugh

105

GTRI's Convert program | National Nuclear Security Administration  

National Nuclear Security Administration (NNSA)

program | National Nuclear Security Administration program | National Nuclear Security Administration Our Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response Recapitalizing Our Infrastructure Continuing Management Reform Countering Nuclear Terrorism About Us Our Programs Our History Who We Are Our Leadership Our Locations Budget Our Operations Media Room Congressional Testimony Fact Sheets Newsletters Press Releases Speeches Events Social Media Video Gallery Photo Gallery NNSA Archive Federal Employment Apply for Our Jobs Our Jobs Working at NNSA Blog GTRI's Convert program Home > About Us > Our Programs > Nonproliferation > Global Threat Reduction Initiative > GTRI's Convert program GTRI's Convert program One of Global Threat Reduction Initiative's (GTRI) three key pillars is

106

coastal loss | NOLA DEFENDER  

U.S. Energy Information Administration (EIA)

BP Oil Doubled Wetland Loss, Study Says Posted Tuesday, ... coastal loss; Deepwater Horizon; louisiana coast; Oil; proceedings of the national academy ...

107

Coupling between switching regulation and torque generation in bacterial flagellar motor  

E-Print Network (OSTI)

The bacterial flagellar motor plays a crucial role in both bacterial locomotion and chemotaxis. Recent experiments reveal that the switching dynamics of the motor depends on the motor rotation speed, and thus the motor torque, non-monotonically. Here we present a unified mathematical model which models motor torque generation based on experimental torque-speed curves and torque-dependent switching based on the conformational spread model. The model successfully reproduces the observed switching rate as a function of the rotation speed, and provides a generic physical explanation independent of most details. A stator affects the switching dynamics through two mechanisms: accelerating the conformation flipping rates of individual rotor switching units, which favours slower motor speed and thus increasing torque; and affecting more switching units within unit time, which favours faster speed. Consequently, the switching rate shows a maximum at intermediate speed. Our model predicts that a motor switches more often with more stators. The load-switching relation may serve as a mechanism for sensing the physical environment, similar to the chemotaxis system for sensing the chemical environment. It may also coordinate the switch dynamics of motors within a cell.

Fan Bai; Tohru Minamino; Zhanghan Wu; Keiichi Namba; Jianhua Xing

2011-06-01T23:59:59.000Z

108

Design and testing of a non-intrusive torque measurement system  

E-Print Network (OSTI)

This thesis details the initial development of a non-intrusive torque measurement system to measure torque in a rotating driveshaft like those commonly found on internal combustion engine powered irrigation pumping plants. A typical driveshaft used in pumping plant applications consists of flanged U-joints on each end with a constant cross-section steele tube portion connecting the U-joints. The photoelectric sensor based system was able to predict torque to within 3?9.1 N-m (346 in-lbs) under constant rpm conditions. Two sensor types, phototransistor and photodiode, were tested. The photodiode sensor was tested with two emitter types: infrared LED and red laser. No significant difference in response was found using either the LED or red laser emmitters. Both the photoelectric and photodiode sensor measurements showed correlation to actual torque. The photoelectric sensor configuration correlation had a standard error of 5?% of a typical natural-gas pumping plant installation running at 773.9 N-m of torque. The sensors were mounted independent of the driveshaft and measured the phaseshift of two pins mounted on the shaft as they passed through the photosensing area. This caused extreme sensitivity to vibration of the engine and driveshaft. A similar design with a temporary mount connected to the shaft and transmitting the response signal via radio frequency telemetry could decrease the effects of vibration on the system.

Wilson, Edwin Ernest

1998-01-01T23:59:59.000Z

109

Waveguide mode converter and method using same  

DOE Patents (OSTI)

A waveguide mode converter converts electromagnetic power being transmitted in a TE.sub.0n or a TM.sub.0n mode, where n is an integer, to an HE.sub.11 mode. The conversion process occurs in a single stage without requiring the power to pass through any intermediate modes. The converter comprises a length of circular corrugated waveguide formed in a multiperiod periodic curve. The period of the curve is selected to couple the desired modes and decouple undesired modes. The corrugation depth is selected to control the phase propagation constant, or wavenumbers, of the input and output modes, thereby preventing coherent coupling to competing modes. In one embodiment, both the period and amplitude of the curve may be selectively adjusted, thereby allowing the converter to be tuned to maximize the conversion efficiency.

Moeller, Charles P. (Del Mar, CA)

1990-01-01T23:59:59.000Z

110

International Peirce-Smith Converting Centennial  

Science Conference Proceedings (OSTI)

... and G. Guzman D. Full Utilization of the Matte Converting Process Energy for Operatiing ... Injection Techniques, Modeling and Process Control. Peirce-Smith ... M. Marinigh. Increasing Capacity and Productivity in the Metals Markets through.

111

Radio frequency digital to analog converter  

E-Print Network (OSTI)

Dynamic performance of high speed, high resolution digital-to-analog converters (DACs) is limited by distortion at the data switching instants. Inter-symbol interference (ISI), imperfect timing synchronization and clock ...

Luschas, Susan, 1975-

2003-01-01T23:59:59.000Z

112

Integrated optical analog-to-digital converter  

E-Print Network (OSTI)

An optically-sampled frequency-demultiplexed wideband analog-to-digital converter (ADC) which has potential to exceed the performance of electronic ADCs by orders of magnitude is studied analytically and numerically. The ...

Khilo, Anatol

2008-01-01T23:59:59.000Z

113

Energy Performance Evaluation of Photovoltaic Power Converters  

Science Conference Proceedings (OSTI)

This work investigates test methods to compare the energy performance of different competing photovoltaic (PV) power converter technologies and topologies. New power converter approaches and technology are regularly introduced in the market, with promises to harness more energy than their competitors. To independently evaluate the performance of these technologies, the Electric Power Research Institute (EPRI) is analyzing existing standards, as well as experimenting with various performance ...

2013-12-23T23:59:59.000Z

114

ANALOG-TO-DIGITAL DATA CONVERTER  

DOE Patents (OSTI)

Electrical apparatus is described, particularly useful in telemetry work, for converting analog signals into electrical pulses and recording them. An electronic editor commands the taking of signal readings at a frequency which varies according to linearity of the analog signal being converted. Readings of information signals are recorded, along with time base readings and serial numbering, if desired, on magnetic tape and the latter may be used to operate a computer or the like. Magnetic tape data may be transferred to punched cards.

Rodgers, G.W.; Althouse, J.E.; Anderson, D.P.; Bussey, G.R.; Minnear, L.H.

1960-09-01T23:59:59.000Z

115

Modeling torque versus speed, shot noise, and rotational diffusion of the bacterial flagellar motor  

E-Print Network (OSTI)

We present a minimal physical model for the flagellar motor that enables bacteria to swim. Our model explains the experimentally measured torque-speed relationship of the proton-driven E. coli motor at various pH and temperature conditions. In particular, the dramatic drop of torque at high rotation speeds (the "knee") is shown to arise from saturation of the proton flux. Moreover, we show that shot noise in the proton current dominates the diffusion of motor rotation at low loads. This suggests a new way to probe the discreteness of the energy source, analogous to measurements of charge quantization in superconducting tunnel junctions.

Thierry Mora; Howard Yu; Ned S. Wingreen

2009-10-05T23:59:59.000Z

116

Alternative Fuels Data Center: Michigan Converts Vehicles to Propane,  

Alternative Fuels and Advanced Vehicles Data Center (EERE)

Michigan Converts Michigan Converts Vehicles to Propane, Reducing Emissions to someone by E-mail Share Alternative Fuels Data Center: Michigan Converts Vehicles to Propane, Reducing Emissions on Facebook Tweet about Alternative Fuels Data Center: Michigan Converts Vehicles to Propane, Reducing Emissions on Twitter Bookmark Alternative Fuels Data Center: Michigan Converts Vehicles to Propane, Reducing Emissions on Google Bookmark Alternative Fuels Data Center: Michigan Converts Vehicles to Propane, Reducing Emissions on Delicious Rank Alternative Fuels Data Center: Michigan Converts Vehicles to Propane, Reducing Emissions on Digg Find More places to share Alternative Fuels Data Center: Michigan Converts Vehicles to Propane, Reducing Emissions on AddThis.com... April 27, 2013

117

State Energy Program Helping Arkansans Convert to Compressed...  

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

State Energy Program Helping Arkansans Convert to Compressed Natural Gas State Energy Program Helping Arkansans Convert to Compressed Natural Gas January 25, 2012 - 4:30pm Addthis...

118

Discussion on the control method of the inductor-converter bridge by simulation and experiment  

DOE Green Energy (OSTI)

With the development of the superconducting magnet as an energy storage unit, pulsed power loads between superconducting magnets of increasing magnitude up to several hundred megawatts or more appear within the realm of possibility. An energy storage unit that is independent of the power grid can be used in applications where the pulsed power required from the power grid may cause a hazardous effect on the power system. An energy transfer system between the storage and the load units eliminates the disturbance on the power grid. An inductor-converter bridge is proposed for such a purpose. The inductor-converter bridge (ICB) is a solid state DC-AC-DC converter system for reversible energy transfer between two high-inductance inductors. The converter thyristors are naturally commutated by a set of wye-connected capacitors on the AC lines of the circuit. The circuit is designed so that, in every converter cycle, a very small fraction of the magnet energy is stored in these capacitors. The characteristics of the inductor-converter bridge are briefly summarized as follows: low energy loss, reversibility of the energy transfer direction, controllability of the energy transfer rate, and no conversion to another energy form.

Hirano, M.; Kustom, R.L.

1983-07-01T23:59:59.000Z

119

System Integration Issues of DC to DC converters in the sLHC Trackers  

E-Print Network (OSTI)

The upgrade of the trackers at the sLHC experiments requires implementing new powering schemes that will provide an increased power density with reduced losses and material budget. A scheme based on buck and switched capacitors DC to DC converters has been proposed as an optimal solution. The buck converter is based on a power ASIC, connected to a custom made air core inductor. The arrangement of the parts and the board layout of the power module are designed to minimize the emissions of EMI in a compact volume, enabling its integration on the tracker modules and staves.

Allongue, B; Faccio, F; Fuentes, c; Michelisa, S; Orlandia, S

2009-01-01T23:59:59.000Z

120

Isolated and soft-switched power converter  

DOE Patents (OSTI)

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

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

2002-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "loss torque converter" 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

Thermionic converters using cylindrical refractory metal emitters  

DOE Green Energy (OSTI)

The construction and operation of four converters is described. Two converters using tantalum emitters operated satisfactorily but temperatures of the order of 2500 deg K were necessary to obtain power densities of 6 watts/cm2. Closer spaced diodes using molybdenum emitters were not initially successful due to internal short circuiting; this was caused partly by evaporated films but mainly by liquid caesium. One of these diodes was modified and yielded 2.6 watts/cm2 at 1610 deg K. (auth)

Bainton, K.F.

1964-09-15T23:59:59.000Z

122

Different methods for direct torque control of induction motor fed from current source inverter  

Science Conference Proceedings (OSTI)

Two different methods for direct torque control (DTC) of induction motor fed from current source inverter (CSI) is analyzed in the paper. The first one is derived from well-known DTC strategy developed for voltage inverter drives. This type of control ... Keywords: CSI, DTC, constant switching, hysteresis comparator, induction motor

Aleksandar Nikolic; Borislav Jeftenic

2008-07-01T23:59:59.000Z

123

Evaluation of force and torque magnitude discrimination thresholds on the human hand-arm system  

Science Conference Proceedings (OSTI)

This article reports on experiments about haptic perception aimed at measuring the force/torque differential thresholds applied to the hand-arm system. The experimental work analyzes how force is sent back to the user by means of a 6 degrees-of-freedom ... Keywords: Force thresholds, perceptual asymmetries, perceptual-based signal processing

M. Vicentini; S. Galvan; D. Botturi; P. Fiorini

2010-10-01T23:59:59.000Z

124

A Self-Learning Solution for Torque Ripple Reduction for Non-Sinusoidal Permanent Magnet  

E-Print Network (OSTI)

1 A Self-Learning Solution for Torque Ripple Reduction for Non-Sinusoidal Permanent Magnet Motor in a permanent-magnet non-sinusoidal synchronous motor. Solutions for calculating optimal currents are deduced are shown to confirm the validity of the proposed neural approach. Index Terms--Permanent Magnet Synchronous

Paris-Sud XI, Université de

125

Optimal Design of Motor and Gear for Drives with High Acceleration and Load Torque  

E-Print Network (OSTI)

Optimal Design of Motor and Gear for Drives with High Acceleration and Load Torque H. Grotstollen-acceleration product are transmitted unchanged by an ideal gear. At a first step those motors can be selected which offer sufficient rated power and power rate. When designing gears for each of these motors two ranges

Noé, Reinhold

126

When Do Losses Count?  

Science Conference Proceedings (OSTI)

Current global and national databases that monitor losses from natural hazards suffer from a number of limitations, which in turn lead to misinterpretation and fallacies concerning the “truthfulness” of hazard loss data. These biases often go ...

Melanie Gall; Kevin A. Borden; Susan L. Cutter

2009-06-01T23:59:59.000Z

127

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

128

Stressing of turbine-generator-exciter shafts by variable-frequency currents superimposed on DC currents in asynchronous HVDC links and following disturbances at converter stations  

SciTech Connect

Ripple currents on the DC side of both HVDC synchronous and asynchronous. Links together with cleared HVDC and AC system disturbances can excite in some circumstances onerous torsional vibrations in large steam generator shafts. The problem has assumed importance in recent months on account of the HVDC Link between Scotland and Northern Ireland going ahead, on account of the proposed Eire/Wales Link, and because AC/DC/AC couplers are to be installed extensively to interconnect the East and West European Grid Systems. This paper discusses and analyses excitation of shaft torsional vibrations in steam turbine-generator-exciter shafts in close proximity to HVDC converter stations by (1) variable-frequency ripple currents superimposed on the DC currents in asynchronous Links, and (2) disturbances at bi-polar converter stations. The time response and tables show that for the systems studied variable-frequency ripple currents superimposed on the DC current in asynchronous Links can excite shaft torsional vibrations, the very small noncharacteristic currents could result in onerous shaft torques which might damage the machine, and that DC line faults at converter stations in close proximity of steam turbine-generator units can excite onerous turbine-generator shaft torsional response. Detailed simulation of the HVDC converter and generator is necessary for precise assessments of shaft torsional response following HVDC converter station faults. 500MW, 660MW, 1000MW and 1300MW machines are considered in the analyses that are made.

Hammons, T.J.; Bremner, J.J. (Univ. of Glasgow (United Kingdom))

1994-09-01T23:59:59.000Z

129

Provably secure convertible undeniable signatures with unambiguity  

Science Conference Proceedings (OSTI)

This paper shows some efficient and provably-secure convertible undeniable signature schemes (with both selective conversion and all conversion), in the standard model and discrete logarithm setting. They further satisfy unambiguity, which is traditionally ... Keywords: anonymous signatures, discrete logarithm, selective/all conversion, standard model, undeniable signatures

Le Trieu Phong; Kaoru Kurosawa; Wakaha Ogata

2010-09-01T23:59:59.000Z

130

Multilevel converters for large electric drives  

SciTech Connect

Traditional two-level high frequency pulse width modulation (PWM) inverters for motor drives have several problems associated with their high frequency switching which produces common-mode voltage and high voltage change (dV/dt) rates to the motor windings. Multilevel inverters solve these problems because their devices can switch at a much lower frequency. Two different multilevel topologies are identified for use as a converter for electric drives, a cascade inverter with separate dc sources and a back-to-back diode clamped converter. The cascade inverter is a natural fit for large automotive all electric drives because of the high VA ratings possible and because it uses several levels of dc voltage sources which would be available from batteries or fuel cells. The back to back diode damped converter is ideal where a source of ac voltage is available such as a hybrid electric vehicle. Simulation and experimental results show the superiority of these two converters over PWM based drives.

Tolbert, L.M.; Peng, F.Z.

1997-11-01T23:59:59.000Z

131

A Dual-Supply Buck Converter with Improved Light-Load Efficiency  

E-Print Network (OSTI)

Power consumption and device size have been placed at the primary concerns for battery-operated portable applications. Switching converters gain popularity in powering portable devices due to their high efficiency, compact sizes and high current delivery capability. However portable devices usually operate at light loads most of the time and are only required to deliver high current in very short periods, while conventional buck converter suffers from low efficiency at light load due to the switching losses that do not scale with load current. In this research, a novel technique for buck converter is proposed to reduce the switching loss by reducing the effective voltage supply at light load. This buck converter, implemented in TSMC 0.18 micrometers CMOS technology, operates with a input voltage of 3.3V and generates an output voltage of 0.9V, delivers a load current from 1mA to 400mA, and achieves 54 percent ~ 91 percent power efficiency. It is designed to work with a constant switching frequency of 3MHz. Without sacrificing output frequency spectrum or output ripple, an efficiency improvement of up to 20 percent is obtained at light load.

Zhang, Chao

2011-05-01T23:59:59.000Z

132

Reactor-relevant quiescent H-mode operation using torque from non-axisymmetric, non-resonant magnetic fields  

Science Conference Proceedings (OSTI)

Results from recent experiments demonstrate that quiescent H-mode (QH-mode) sustained by magnetic torque from non-axisymmetric magnetic fields is a promising operating mode for future burning plasmas. Using magnetic torque from n=3 fields to replace counter-I{sub p} torque from neutral beam injection (NBI), we have achieved long duration, counter-rotating QH-mode operation with NBI torque ranging from counter-I{sub p} to up to co-I{sub p} values of 1-1.3 Nm. This co-I{sub p} torque is 3 to 4 times the scaled torque that ITER will have. These experiments utilized an ITER-relevant lower single-null plasma shape and were done with ITER-relevant values of {nu}{sub ped}{sup *} and {beta}{sub N}{sup ped}. These discharges exhibited confinement quality H{sub 98y2}=1.3, in the range required for ITER. In preliminary experiments using n=3 fields only from a coil outside the toroidal coil, QH-mode plasmas with low q{sub 95}=3.4 have reached fusion gain values of G={beta}{sub N}H{sub 89}/q{sub 95}{sup 2}=0.4, which is the desired value for ITER. Shots with the same coil configuration also operated with net zero NBI torque. The limits on G and co-I{sub p} torque have not yet been established for this coil configuration. QH-mode work to has made significant contact with theory. The importance of edge rotational shear is consistent with peeling-ballooning mode theory. Qualitative and quantitative agreements with the predicted neoclassical toroidal viscosity torque is seen.

Burrell, K. H.; Garofalo, A. M; Osborne, T. H.; Schaffer, M. J.; Snyder, P. B. [General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States); Solomon, W. M.; Park, J.-K. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Fenstermacher, M. E. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

2012-05-15T23:59:59.000Z

133

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

E-Print Network (OSTI)

Significant advances in modern ac/ac power converter technologies and demands of industries have reached beyond standard ac/ac power converters with voltage-source inverters fed from diode rectifiers. Power electronics converters have been matured to stages toward compact realization, increased high-power handling capability, and improving utility interface. Modern ac/ac power converter topologies with various control strategies have been introduced for the further improvements, such as matrix converters, current-fed converters, PWM rectifiers, and active power filters. In this dissertation, several new converter topologies are proposed in conjunction with developed control schemes based on the modern ac/ac converters which enhance performance and solve the drawbacks of conventional converters. In this study, a new fault-tolerant PWM strategy is first proposed for matrix converters. The added fault-tolerant scheme would strengthen the matrix converter technology for aerospace and military applications. A modulation strategy is developed to reshape output currents for continuous operation, against fault occurrence in matrix converter drives. This study designs a hybrid, high-performance ac/ac power converter for high power applications, based on a high-power load commutated inverter and a mediumpower voltage source inverter. Natural commutation of the load commutated inverter is actively controlled by the voltage source inverter. In addition, the developed hybrid system ensures sinusoidal output current/voltage waveforms and fast dynamic response in high power areas. A new topology and control scheme for a six-step current source inverter is proposed. The proposed topology utilizes a small voltage source inverter, to turn off main thyristor switches, transfer reactive load energy, and limit peak voltages across loads. The proposed topology maximizes benefits of the constituent converters: highpower handling capability of large thyristor-based current source inverters as well as fast and easy control of small voltage source inverters. This study analyzes, compares, and evaluates two topologies for unity power factor and multiple ac/ac power conversions. Theoretical analyses and comparisons of the two topologies, grounded on mathematical approaches, are presented from the standpoint of converter kVA ratings, dc-link voltage requirements, switch ratings, semiconductor losses, and reactive component sizes. Analysis, simulation, and experimental results are detailed for each proposed topology.

Kwak, Sangshin

2006-05-01T23:59:59.000Z

134

A square root analog to digital converter to optimally convert photonic signals for computed tomography  

E-Print Network (OSTI)

The arrival of photons at a given location is a Poisson process with an associated shot noise which rises with the square root of the number of photons received. An analog-to-digital converter (ADC) with a square root ...

Bieniosek, Matthew (Matthew F.)

2010-01-01T23:59:59.000Z

135

Distribution System Losses Evaluation  

Science Conference Proceedings (OSTI)

Currently, there is not an industry standard on how utilities calculate and account for electrical losses and reductions in electric system losses. Computer models used to analyze power flows typically only include the primary components of the distribution system infrastructure. More detailed electric system models can benefit utilities by providing more accurate loss calculations as well as benefits for system planning and engineering. The utility industry could benefit from having a consistent and uni...

2008-12-16T23:59:59.000Z

136

Alternative Fuels Data Center: Landfills Convert Biogas Into Renewable  

Alternative Fuels and Advanced Vehicles Data Center (EERE)

Landfills Convert Landfills Convert Biogas Into Renewable Natural Gas to someone by E-mail Share Alternative Fuels Data Center: Landfills Convert Biogas Into Renewable Natural Gas on Facebook Tweet about Alternative Fuels Data Center: Landfills Convert Biogas Into Renewable Natural Gas on Twitter Bookmark Alternative Fuels Data Center: Landfills Convert Biogas Into Renewable Natural Gas on Google Bookmark Alternative Fuels Data Center: Landfills Convert Biogas Into Renewable Natural Gas on Delicious Rank Alternative Fuels Data Center: Landfills Convert Biogas Into Renewable Natural Gas on Digg Find More places to share Alternative Fuels Data Center: Landfills Convert Biogas Into Renewable Natural Gas on AddThis.com... May 25, 2013 Landfills Convert Biogas Into Renewable Natural Gas

137

Component technology for Stirling power converters  

DOE Green Energy (OSTI)

NASA Lewis Research Center has organized a component technology program as part of the efforts to develop Stirling converter technology for space power applications. The Stirling space power program is part of the NASA High Capacity Power Project of the Civil Space Technology Initiative (CSTI). NASA Lewis is also providing technical management for a DOE/Sandia program to develop Stirling converters for solar terrestrial power producing electricity for the utility grid. The primary contractors for the space power and solar terrestrial programs develop component technologies directly related to their program goals. This Lewis component technology effort, while coordinated with the main programs, aims at longer term issues, advanced technologies, and independent assessments. This paper will present an overview of work on linear alternators, engine/alternator/load interactions and controls, heat exchangers, materials, life and reliability, and bearings.

Thieme, L.G.

1994-09-01T23:59:59.000Z

138

APPARATUS FOR CONVERTING HEAT INTO ELECTRICITY  

DOE Patents (OSTI)

This patent shows an apparatus for converting heat to electricity. It includes a galvanic cell having an anodic metal anode, a fused salt electrolyte, and a hydrogen cathode having a diffusible metal barrier of silver-- palladium alloy covered with sputtered iron on the side next to the fused electrolyte. Also shown is a regenerator for regenerating metal hydride produced by the galvanic cell into hydrogen gas and anodic metal, both of which are recycled. (AEC)

Crouthamel, C.E.; Foster, M.S.

1964-01-28T23:59:59.000Z

139

Spectral converters and luminescent solar concentrators  

E-Print Network (OSTI)

In this paper we present a comprehensive theoretical description of molecular spectral converters in the specific context of Luminescent Solar Concentrators (LSCs). The theoretical model is an extension to a three-level system interacting with a solar radiation bath of the standard quantum theory of atomic radiative processes. We derive the equilibrium equations of the conversion process and provide specific examples of application of this principle to the development of solar concentration devices.

Petra F. Scudo; Luigi Abbondanza; Roberto Fusco

2009-07-21T23:59:59.000Z

140

Spectral converters and luminescent solar concentrators  

E-Print Network (OSTI)

In this paper we present a comprehensive theoretical description of molecular spectral converters in the specific context of Luminescent Solar Concentrators (LSCs). The theoretical model is an extension to a three-level system interacting with a solar radiation bath of the standard quantum theory of atomic radiative processes. We derive the equilibrium equations of the conversion process and provide specific examples of application of this principle to the development of solar concentration devices.

Scudo, Petra F; Fusco, Roberto

2009-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "loss torque converter" 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

Alignment of cylindrical colloids near chemically patterned substrates induced by critical Casimir torques  

E-Print Network (OSTI)

Recent experiments have demonstrated a fluctuation-induced lateral trapping of spherical colloidal particles immersed in a binary liquid mixture near its critical demixing point and exposed to chemically patterned substrates. Inspired by these experiments, we study this kind of effective interaction, known as the critical Casimir effect, for elongated colloids of cylindrical shape. This adds orientational degrees of freedom. When the colloidal particles are close to a chemically structured substrate, a critical Casimir torque acting on the colloids emerges. We calculate this torque on the basis of the Derjaguin approximation. The range of validity of the latter is assessed via mean-field theory. This assessment shows that the Derjaguin approximation is reliable in experimentally relevant regimes, so that we extend it to Janus particles endowed with opposing adsorption preferences. Our analysis indicates that critical Casimir interactions are capable to achieve well-defined, reversible alignments both of chemically homogeneous and of Janus cylinders.

M. Labbé-Laurent; M. Tröndle; L. Harnau; S. Dietrich

2013-11-15T23:59:59.000Z

142

Energy losses in switches  

DOE Green Energy (OSTI)

The authors experiments show energy losses between 2 and 10 times that of the resistive time predictions. The experiments used hydrogen, helium, air, nitrogen, SF{sub 6} polyethylene, and water for the switching dielectric. Previously underestimated switch losses have caused over predicting the accelerator outputs. Accurate estimation of these losses is now necessary for new high-efficiency pulsed power devices where the switching losses constitute the major portion of the total energy loss. They found that the switch energy losses scale as (V{sub peak}I{sub peak}){sup 1.1846}. When using this scaling, the energy losses in any of the tested dielectrics are almost the same. This relationship is valid for several orders of magnitude and suggested a theoretical basis for these results. Currents up to .65 MA, with voltages to 3 MV were applied to various gaps during these experiments. The authors data and the developed theory indicates that the switch power loss continues for a much longer time than the resistive time, with peak power loss generally occurring at peak current in a ranging discharge instead of the early current time. All of the experiments were circuit code modeled after developing a new switch loss version based on the theory. The circuit code predicts switch energy loss and peak currents as a function of time. During analysis of the data they noticed slight constant offsets between the theory and data that depended on the dielectric. They modified the plasma conductivity for each tested dielectric to lessen this offset.

Martin, T.H.; Seamen, J.F.; Jobe, D.O.

1993-07-01T23:59:59.000Z

143

Development of highly magnetostrictive composites for applications in magnetomechanical torque sensors  

DOE Green Energy (OSTI)

The objective of this work was to investigate and develop a magnetomechanical material with high magnetomechanical response and low hysteresis. This material will be used in electronic torque sensors for advanced steering systems in automobiles which will replace the costly and fuel inefficient hydraulic steering systems currently in use. Magnetostruction and the magnetomechanical effect under torsional stress of magnetostrictive composites have been investigated in the present study.

Chen, Yonghua

1999-12-01T23:59:59.000Z

144

Predicting makeup torque of threaded tapered connections and evaluation of coefficients of friction  

SciTech Connect

This paper will show how it is possible to generate a general purpose formula to determine the amount of torque required to make up non-shouldering tapered threaded connections as are commonly used on tubing and casing connections. In addition, by manipulating this algorithm, values for the dynamic coefficient of friction of thread compounds may be derived. This algorithm allows any type of thread form to be analyzed and was verified through actual testing.

Hawke, M.C.

1984-09-01T23:59:59.000Z

145

Optical forces and optical torques on various materials arising from optical lattices in the Lorentz-Mie regime  

E-Print Network (OSTI)

By combining the Maxwell stress tensor with the finite-difference time-domain (FDTD) method, we calculate the optical force and optical torque on particles from optical lattices. We compare our method to the two-component ...

Jia, Lin

146

Please do not use the torque directive mppnppn in your job scrpts  

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

Please do not use the torque directive mppnppn in your Please do not use the torque directive mppnppn in your job scrpts Please do not use the torque directive mppnppn in your job scrpts August 2, 2013 (0 Comments) As of 8/15 12:30 PDT, the submit filter was updated to allow the #PBS -l nodes directive to be used in the jobs submitted through batch scripts. We are still experimenting with this directive, please report any problem you see with this directive. 8/21/2013 Edison has some issues with the explicit use of #PBS -l mppnppn=48 to use Hyper-Threading (HT). Please do not use it. To run with Hyper-Threading, please request needed nodes as you would normally do for a non-HT job, ie., use mppwidth/24 to request the number of nodes you need, and then use the aprun option -j2 to use all the cores on the nodes. So the following job

147

Modeling the Loss Distribution  

Science Conference Proceedings (OSTI)

In this paper, we focus on modeling and predicting the loss distribution for credit risky assets such as bonds and loans. We model the probability of default and the recovery rate given default based on shared covariates. We develop a new class of default ... Keywords: Basel II, default prediction, loss distribution, recovery rates

Sudheer Chava; Catalina Stefanescu; Stuart Turnbull

2011-07-01T23:59:59.000Z

148

Modelling, simulation and analysis of low-cost direct torque control of PMSM using hall-effect sensors  

E-Print Network (OSTI)

This thesis focuses on the development of a novel Direct Torque Control (DTC) scheme for permanent magnet (PM) synchronous motors (surface and interior types) in the constant torque region with the help of cost-effective hall-effect sensors. This method requires no DC-link sensing, which is a mandatory matter in the conventional DTC drives, therefore it reduces the cost of a conventional DTC of a permanent magnet (PM) synchronous motor and also removes common problems including; resistance change effect, low speed and integration drift. Conventional DTC drives require at least one DC-link voltage sensor (or two on the motor terminals) and two current sensors because of the necessary estimation of position, speed, torque, and stator flux in the stationary reference frame. Unlike the conventional DTC drive, the proposed method uses the rotor reference frame because the rotor position is provided by the three hall-effect sensors and does not require expensive voltage sensors. Moreover, the proposed algorithm takes the acceleration and deceleration of the motor and torque disturbances into account to improve the speed and torque responses. The basic theory of operation for the proposed topology is presented. A mathematical model for the proposed DTC of the PMSM topology is developed. A simulation program written in MATLAB/SIMULINK�® is used to verify the basic operation (performance) of the proposed topology. The mathematical model is capable of simulating the steady-state, as well as dynamic response even under heavy load conditions (e.g. transient load torque at ramp up). It is believed that the proposed system offers a reliable and low-cost solution for the emerging market of DTC for PMSM drives. Finally the proposed drive, considering the constant torque region operation, is applied to the agitation part of a laundry washing machine (operating in constant torque region) for speed performance comparison with the current low-cost agitation cycle speed control technique used by washing machine companies around the world.

Ozturk, Salih Baris

2005-12-01T23:59:59.000Z

149

Alternative Fuels Data Center: Virginia Converts Vehicles to Propane in  

Alternative Fuels and Advanced Vehicles Data Center (EERE)

Virginia Converts Virginia Converts Vehicles to Propane in Spotsylvania County to someone by E-mail Share Alternative Fuels Data Center: Virginia Converts Vehicles to Propane in Spotsylvania County on Facebook Tweet about Alternative Fuels Data Center: Virginia Converts Vehicles to Propane in Spotsylvania County on Twitter Bookmark Alternative Fuels Data Center: Virginia Converts Vehicles to Propane in Spotsylvania County on Google Bookmark Alternative Fuels Data Center: Virginia Converts Vehicles to Propane in Spotsylvania County on Delicious Rank Alternative Fuels Data Center: Virginia Converts Vehicles to Propane in Spotsylvania County on Digg Find More places to share Alternative Fuels Data Center: Virginia Converts Vehicles to Propane in Spotsylvania County on AddThis.com...

150

Alternative Fuels Data Center: Empire Coachworks Converts Limousines to  

Alternative Fuels and Advanced Vehicles Data Center (EERE)

Empire Coachworks Empire Coachworks Converts Limousines to Natural Gas to someone by E-mail Share Alternative Fuels Data Center: Empire Coachworks Converts Limousines to Natural Gas on Facebook Tweet about Alternative Fuels Data Center: Empire Coachworks Converts Limousines to Natural Gas on Twitter Bookmark Alternative Fuels Data Center: Empire Coachworks Converts Limousines to Natural Gas on Google Bookmark Alternative Fuels Data Center: Empire Coachworks Converts Limousines to Natural Gas on Delicious Rank Alternative Fuels Data Center: Empire Coachworks Converts Limousines to Natural Gas on Digg Find More places to share Alternative Fuels Data Center: Empire Coachworks Converts Limousines to Natural Gas on AddThis.com... Jan. 14, 2010 Empire Coachworks Converts Limousines to Natural Gas

151

Alternative Fuels Data Center: Atlanta Airport Converts Shuttles to CNG  

Alternative Fuels and Advanced Vehicles Data Center (EERE)

Atlanta Airport Atlanta Airport Converts Shuttles to CNG to someone by E-mail Share Alternative Fuels Data Center: Atlanta Airport Converts Shuttles to CNG on Facebook Tweet about Alternative Fuels Data Center: Atlanta Airport Converts Shuttles to CNG on Twitter Bookmark Alternative Fuels Data Center: Atlanta Airport Converts Shuttles to CNG on Google Bookmark Alternative Fuels Data Center: Atlanta Airport Converts Shuttles to CNG on Delicious Rank Alternative Fuels Data Center: Atlanta Airport Converts Shuttles to CNG on Digg Find More places to share Alternative Fuels Data Center: Atlanta Airport Converts Shuttles to CNG on AddThis.com... Sept. 9, 2012 Atlanta Airport Converts Shuttles to CNG L earn how an Atlanta company saves money and conserves fuel with compressed natural gas airport shuttles.

152

Alternative Fuels Data Center: Veolia Transportation Converts Taxi Fleet to  

Alternative Fuels and Advanced Vehicles Data Center (EERE)

Veolia Transportation Veolia Transportation Converts Taxi Fleet to Propane to someone by E-mail Share Alternative Fuels Data Center: Veolia Transportation Converts Taxi Fleet to Propane on Facebook Tweet about Alternative Fuels Data Center: Veolia Transportation Converts Taxi Fleet to Propane on Twitter Bookmark Alternative Fuels Data Center: Veolia Transportation Converts Taxi Fleet to Propane on Google Bookmark Alternative Fuels Data Center: Veolia Transportation Converts Taxi Fleet to Propane on Delicious Rank Alternative Fuels Data Center: Veolia Transportation Converts Taxi Fleet to Propane on Digg Find More places to share Alternative Fuels Data Center: Veolia Transportation Converts Taxi Fleet to Propane on AddThis.com... Aug. 17, 2013 Veolia Transportation Converts Taxi Fleet to Propane

153

2008 High-Megawatt Power Converter Technology R&D ...  

Science Conference Proceedings (OSTI)

... 2008 High-Megawatt Power Converter Technology R&D Roadmap Workshop. NIST, Gaithersburg, MD. April 8, 2008. On ...

2013-05-30T23:59:59.000Z

154

Solid state transport-based thermoelectric converter - Energy ...  

A solid state thermoelectric converter includes a thermally insulating separator layer, ... Advanced Materials; Biomass and Biofuels; Building Energy Efficiency;

155

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

156

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

157

Solar-energy-process-converter system  

SciTech Connect

A solar-energy-process-converter system whereby the energy from the sun is accumulated and projected by a parabolic reflector so as to impinge upon a cluster of thermocouples to create electrical energy for activating an electrolysis unit through which hydrogen and oxygen are generated and stored. The system can also include a steam-turbine electrical-generator plant that is adapted to be operated by the burning of the hydrogen and oxygen, and the gases can further be used to establish heat to drive a thermocouple electrical-generator plant, wherein the stored hydrogen is further employed as a fuel for vehicle and other engines.

Shinn, W.A.

1981-01-20T23:59:59.000Z

158

Generator loss of field study for AEP's Rockport plant  

SciTech Connect

Generator loss of field (LOF) conditions occur rarely. However, when LOF and consequent out-of-step conditions occur, the resultant high currents and pulsating torques can damage the turbine-generator under some conditions. Also the electrical system near the disturbance can be impacted by abnormal levels and cyclic swings of power, VArs, and voltages. This article describes the computed performance of AEP's remotely-located 2600 MW Rockport plant after simulated LOF disturbances to one of its 1300 MW cross-compound units. It shows the transmission facilities near Rockport, as well as nearby plants. Because of this topology, LOF on one unit can significantly impact the adjacent Rockport unit, and the reactive power drain could impose a heavy burden on transmission, impacting local voltages.

Rana, R.D.; Schulz, R.P.; Heyeck, M.; Boyer, T.R. Jr. (American Electric Power, Inc., Canton, OH (USA))

1990-04-01T23:59:59.000Z

159

Single Inductor Dual Output Buck Converter  

E-Print Network (OSTI)

The portable electronics market is rapidly migrating towards more compact devices with multiple functionalities. Form factor, performance, cost and efficiency of these devices constitute the factors of merit of devices like cell phones, MP3 players and PDA's. With advancement in technology and more intelligent processors being used, there is a need for multiple high integrity voltage supplies for empowering the systems in portable electronic devices. Switched mode power supplies (SMPS's) are used to regulate the battery voltage. In an SMPS, maximum area is taken by the passive components such as the inductor and the capacitor. This work demonstrates a single inductor used in a buck converter with two output voltages from an input battery with voltage of value 3V. The main focus areas are low cross regulation between the outputs and supply of completely independent load current levels while maintaining desired values (1.2V,1.5V) within well controlled ripple levels. Dynamic hysteresis control is used for the single inductor dual output buck converter in this work. Results of schematic and post layout simulations performed in CADENCE prove the merits of this control method, such as nil cross regulation and excellent transient response.

Eachempatti, Haritha

2009-05-01T23:59:59.000Z

160

Alternative Fuels Data Center: Golden Eagle Distributors Inc. to Convert  

Alternative Fuels and Advanced Vehicles Data Center (EERE)

Golden Eagle Golden Eagle Distributors Inc. to Convert Entire Fleet to CNG to someone by E-mail Share Alternative Fuels Data Center: Golden Eagle Distributors Inc. to Convert Entire Fleet to CNG on Facebook Tweet about Alternative Fuels Data Center: Golden Eagle Distributors Inc. to Convert Entire Fleet to CNG on Twitter Bookmark Alternative Fuels Data Center: Golden Eagle Distributors Inc. to Convert Entire Fleet to CNG on Google Bookmark Alternative Fuels Data Center: Golden Eagle Distributors Inc. to Convert Entire Fleet to CNG on Delicious Rank Alternative Fuels Data Center: Golden Eagle Distributors Inc. to Convert Entire Fleet to CNG on Digg Find More places to share Alternative Fuels Data Center: Golden Eagle Distributors Inc. to Convert Entire Fleet to CNG on AddThis.com...

Note: This page contains sample records for the topic "loss torque converter" 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

Zero-switching-loss inverters for high-power applications  

SciTech Connect

The development of zero-switching-loss inverters has attracted much interest for industrial applications. The resonant dc link inverter (RDCLI) provides a simple and robust approach for realizing switching frequencies >20 kHz in multi-kilowatt systems but impresses substantial voltage stress (-- 2.5 supply voltage) across the devices. Two alternate topologies for realizing zero switching losses in high-power converters are proposed. The actively clamped resonant dc-link inverter (ACRLI) uses the concept of a lossless active clamp to restrict voltage stresses to only 1.3-1.5 supply voltage (V/sub s/) while maintaining a mode of operation similar to the RDCLI. For applications demanding substantially superior spectral performance, the resonant pole inverter (RPI), also called the quasi-resonant current mode inverter (QRCMI), is proposed as a viable topology. Detailed analysis, simulation, and experimental results are presented to verify operation principles of both power converters.

Divan, D.M.; Skibinski, G. (Wisconsin Univ., Madison, WI (USA). Dept. of Electrical and Computer Engineering)

1989-07-01T23:59:59.000Z

162

Instantaneous engine frictional torque, its components and piston assembly friction. Final report  

DOE Green Energy (OSTI)

The overall goal of this report is to document the work done to determine the instantaneous frictional torque of internal combustion engine by using a new approach known as (P-{omega}) method developed at Wayne State University. The emphasis has been to improve the accuracy of the method, and apply it to both diesel and gasoline engines under different operating conditions. Also work included an investigation to determine the effect of using advanced materials and techniques to coat the piston rings on the instantaneous engine frictional torque and the piston assembly friction. The errors in measuring the angular velocity, {omega}, have been determined and found to be caused by variations in the divisions within one encoder, encoder-to-encoder variations, misalignment within the encoder itself and misalignment between the encoder and crankshaft. The errors in measuring the cylinder gas pressure, P, have been determined and found to be caused by transducer-to-transducer variations, zero drift, thermal stresses and lack of linearity. The ability of the (P-{omega}) method in determining the frictional torque of many engine components has been demonstrated. These components include valve train, fuel injection pump with and without fuel injection, and piston with and without different ring combinations. The emphasis in this part of the research program has been on the piston-ring assembly friction. The effects of load and other operating variables on IFT have been determined. The motoring test, which is widely used in industry to measure engine friction has been found to be inaccurate. The errors have been determined at different loads.

Nichols, F.A. [ed.] [Argonne National Lab., IL (United States); Henein, N.A. [Wayne State Univ., Detroit, MI (United States). Center for Automotive Research

1992-05-01T23:59:59.000Z

163

Synchronization of an array of spin torque nano oscillators in periodic applied external magnetic field  

E-Print Network (OSTI)

Considering an array of spin torque transfer nano oscillators (STNOs), we have investigated the synchronization property of the system under the action of a common periodically driven applied external magnetic field by numerically analyzing the underlying system of Landau-Lifshitz-Gilbert-Slonczewski (LLGS) equations for the macro-spin variables. We find the novel result that the applied external magnetic field can act as a medium to induce synchronization of periodic oscillations, both in-phase and anti-phase, even without coupling through spin current, thereby leading to the exciting possibility of enhancement of microwave power in a straightforward way.

B. Subash; V. K. Chandrasekar; M. Lakshmanan

2013-04-03T23:59:59.000Z

164

Control of a dynamic brake to reduce turbine-generator shaft transient torques  

SciTech Connect

A resistive, thyristor-controlled brake is used to damp transient torques in large thermo-electric generators supplying series-compensated transmission lines. Emphasis is placed on developing a suitable control algorithm and testing the algorithm through a wide variety of different operating configurations. Discrete-level Generalized Predictive Control is examined as one possible approach to optimal control of the brake. Some problems with implementation of GPC on the system are discussed. Prony analysis is used to identify system transfer functions which are then related to control design considerations and robustness properties.

Donnelly, M.K.; Smith, J.R.; Johnson, R.M. (Montana State Univ., Bozeman, MT (United States)); Hauer, J.F. (Bonneville Power Administration, Kalispell, MT (United States)); Brush, R.W. (Montana Power Co., Butte, MT (United States)); Adapa, R. (Electric Power Research Inst., Palo Alto, CA (United States))

1993-02-01T23:59:59.000Z

165

Converting syncrudes to transportation fuels: Appendix 1  

DOE Green Energy (OSTI)

Syncrudes derived from oil shale and those produced in direct coal liquefaction processes can be converted to transportation fuels using modern commercial hydroprocessing technology. Upgrading routes typically consist of hydrogen addition and removal of heteroatom and inorganic impurities. This paper reviews refining routes and discusses the properties of finished transportation fuel products (gasoline, jet fuel, diesel) produced from syncrudes. Fuels produced from bituminous coal, subbituminous coal, and lignite are contrasted with those produced from oil shale and petroleum. Transportation fuels from shale oil resemble those from waxy petroleum crudes. Upgraded products from liquids made in H-Coal, EDS, and SRC-II direct coal liquefaction processes are low in paraffin content and consist mainly of cyclic hydrocarbons. As a result, the latter have some unusual and desirable properties for transportation fuels. 14 refs., 8 figs., 8 tabs.

Sullivan, R.F.; O'Rear, D.J.; Frumkin, H.A.

1981-01-01T23:59:59.000Z

166

Converting energy from fusion into useful forms  

E-Print Network (OSTI)

If fusion power reactors are to be feasible, it will still be necessary to convert the energy of the nuclear reaction into usable form. The heat produced will be removed from the reactor core by a primary coolant, which might be water, helium, molten lithium-lead, molten lithium-containing salt, or CO2. The heat could then be transferred to a conventional Rankine cycle or Brayton (gas turbine) cycle. Alternatively it could be used for thermochemical processes such as producing hydrogen or other transport fuels. Fusion presents new problems because of the high energy neutrons released. These affect the selection of materials and the operating temperature, ultimately determining the choice of coolant and working cycle. The limited temperature ranges allowed by present day irradiated structural materials, combined with the large internal power demand of the plant, will limit the overall thermal efficiency. The operating conditions of the fusion power source, the materials, coolant, and energy conversion system w...

Kovari, M; Jenkins, I; Kiely, C

2014-01-01T23:59:59.000Z

167

Modular Power Converters for PV Applications  

DOE Green Energy (OSTI)

This report describes technical opportunities to serve as parts of a technological roadmap for Shoals Technologies Group in power electronics for PV applications. There are many different power converter circuits that can be used for solar inverter applications. The present applications do not take advantage of the potential for using common modules. We envision that the development of a power electronics module could enable higher reliability by being durable and flexible. Modules would have fault current limiting features and detection circuits such that they can limit the current through the module from external faults and can identify and isolate internal faults such that the remaining modules can continue to operate with only minimal disturbance to the utility or customer. Development of a reliable, efficient, low-cost, power electronics module will be a key enabling technology for harnessing more power from solar panels and enable plug and play operation. Power electronics for computer power supplies, communication equipment, and transportation have all targeted reliability and modularity as key requirements and have begun concerted efforts to replace monolithic components with collections of common smart modules. This is happening on several levels including (1) device level with intelligent control, (2) functional module level, and (3) system module. This same effort is needed in power electronics for solar applications. Development of modular units will result in standard power electronic converters that will have a lower installed and operating cost for the overall system. These units will lead to increased adaptability and flexibility of solar inverters. Incorporating autonomous fault current limiting and reconfiguration capabilities into the modules and having redundant modules will lead to a durable converter that can withstand the rigors of solar power generation for more than 30 years. Our vision for the technology roadmap is that there is no need for detailed design of new power converters for each new application or installation. One set of modules and controllers can be pre-developed and the only design question would be how many modules need to be in series or parallel for the specific power requirement. Then, a designer can put the modules together and add the intelligent reconfigurable controller. The controller determines how many modules are connected, but it might also ask for user input for the specific application during setup. The modules include protection against faults and can reset it, if necessary. In case of a power device failure, the controller reconfigures itself to continue limited operation until repair which might be as simple as taking the faulty module out and inserting a new module. The result is cost savings in design, maintenance, repair, and a grid that is more reliable and available. This concept would be a perfect fit for the recently announced funding opportunity announcement (DE-FOA-0000653) on Plug and Play Photovoltaics.

Ozpineci, Burak [ORNL; Tolbert, Leon M [ORNL

2012-05-01T23:59:59.000Z

168

Method and apparatus for effecting light-off of a catalytic converter in a hybrid powertrain system  

SciTech Connect

A powertrain system includes a hybrid transmission and an internal combustion engine coupled to an exhaust aftertreatment device. A method for operating the powertrain system includes operating the hybrid transmission to generate tractive torque responsive to an operator torque request with the internal combustion engine in an engine-off state so long as the tractive torque is less than a threshold. The internal combustion engine is operated in an engine-on state at preferred operating conditions to effect light-off of the exhaust aftertreatment device and the hybrid transmission is coincidentally operated to generate tractive torque responsive to the operator torque request when the operator torque request exceeds the threshold. The internal combustion engine is then operated in the engine-on state to generate tractive torque responsive to the operator torque request.

Roos, Bryan Nathaniel; Spohn, Brian L

2013-07-02T23:59:59.000Z

169

Catalogue of a Loss  

E-Print Network (OSTI)

Catalogue of a Loss is a collection of sixty-two prose poems written within the past year and half. The work is printed on 4x6 cards. Each poem may be read individually from a single card or the poems can be read in ...

Berger, Larisa (Larisa A.)

2012-01-01T23:59:59.000Z

170

DYNAMIC ANALYSIS OF THE BULK TRITIUM SHIPPING PACKAGE SUBJECTED TO CLOSURE TORQUES AND SEQUENTIAL IMPACTS  

SciTech Connect

This paper presents a finite-element technique to simulate the structural responses and to evaluate the cumulative damage of a radioactive material packaging requiring bolt closure-tightening torque and subjected to the scenarios of the Hypothetical Accident Conditions (HAC) defined in the Code of Federal Regulations Title 10 part 71 (10CFR71). Existing finite-element methods for modeling closure stresses from bolt pre-load are not readily adaptable to dynamic analyses. The HAC events are required to occur sequentially per 10CFR71 and thus the evaluation of the cumulative damage is desirable. Generally, each HAC event is analyzed separately and the cumulative damage is partially addressed by superposition. This results in relying on additional physical testing to comply with 10CFR71 requirements for assessment of cumulative damage. The proposed technique utilizes the combination of kinematic constraints, rigid-body motions and structural deformations to overcome some of the difficulties encountered in modeling the effect of cumulative damage. This methodology provides improved numerical solutions in compliance with the 10CFR71 requirements for sequential HAC tests. Analyses were performed for the Bulk Tritium Shipping Package (BTSP) designed by Savannah River National Laboratory to demonstrate the applications of the technique. The methodology proposed simulates the closure bolt torque preload followed by the sequential HAC events, the 30-foot drop and the 30-foot dynamic crush. The analytical results will be compared to the package test data.

Wu, T; Paul Blanton, P; Kurt Eberl, K

2007-07-09T23:59:59.000Z

171

Integrated Solar Power Converters: Wafer-Level Sub-Module Integrated DC/DC Converter  

Science Conference Proceedings (OSTI)

Solar ADEPT Project: CU-Boulder is developing advanced power conversion components that can be integrated into individual solar panels to improve energy yields. The solar energy that is absorbed and collected by a solar panel is converted into useable energy for the grid through an electronic component called an inverter. Many large, conventional solar energy systems use one, central inverter to convert energy. CU-Boulder is integrating smaller, microinverters into individual solar panels to improve the efficiency of energy collection. The University’s microinverters rely on electrical components that direct energy at high speeds and ensure that minimal energy is lost during the conversion process—improving the overall efficiency of the power conversion process. CU-Boulder is designing its power conversion devices for use on any type of solar panel.

None

2012-02-09T23:59:59.000Z

172

Manufacturing cost of flame heated thermionic converters. Topical report  

DOE Green Energy (OSTI)

The cost of thermionic converters has been estimated in support of the cost calculations for thermionic topping of central station powerplants. These calculations supersede the previous calculations made in 1975 and use a design concept similar to the current configuration of flame-heated converters. The cost of converters was estimated by obtaining quotations from manufactureres whenever possible. The selling cost was found to be $110 per kilowatt.

LaRue, G.; Miskolczy, G.

1979-04-01T23:59:59.000Z

173

Modeling and Controller Design of a Wind Energy Conversion System Including a Matrix Converter.  

E-Print Network (OSTI)

??In this thesis, a grid-connected wind-energy converter system including a matrix converter is proposed. The matrix converter, as a power electronic converter, is used to… (more)

Barakati, Seyed Masoud

2008-01-01T23:59:59.000Z

174

Tests with a line-commutated converter as a variable inductive load on the Bonneville Power Administration transmission system  

DOE Green Energy (OSTI)

A twelve-pulse, line-commutated converter, with a steady-state rating of 2.5 kV and 5.5 kA, formerly used for charging and discharging a superconducting magnet, was reconfigured as a static reactive power load. Tests staged at the Tacoma, WA, substation of the Bonneville Power Administration (BPA) revealed that the converter could be used as a variable inductive load, provided a stable current controller was installed. The unit was modulated as a variable VAR load following a sinusoidal VAR demand signal with an amplitude up to 14.8 MVAR. The total losses at maximum VAR output were 370 kW. This paper explains the necessary modifications of the converter to operate as a variable reactive load. Measured current waveshapes are analyzed. The effects of such a load on the BPA transmission system are presented.

Boenig, H.J.; Hauer, J.F.; Nielsen, R.G.

1986-01-01T23:59:59.000Z

175

GTRI's Convert Program: Minimizing the Use of Highly Enriched...  

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

Flickr RSS Twitter YouTube GTRI's Convert Program: Minimizing the Use of Highly Enriched Uranium | National Nuclear Security Administration Our Mission Managing the Stockpile...

176

Improvements on Converter Operating Practice at Mufulira Smelter ...  

Science Conference Proceedings (OSTI)

Abstract Scope, With the commisioning of the 850,000 tonnes of Concentrate treated per annum capacity Isasmelt in September 2006 the Converter section ...

177

Research Projects to Convert Captured CO2 Emissions to Useful...  

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

July 06, 2010 Research Projects to Convert Captured CO2 Emissions to Useful Products Six Projects Selected by DOE Will Further Important Technologies for Helping Reduce CO2...

178

Weekly Wrap-Up: Testing Wind Blades, Converting Carbon Emissions...  

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

Chu announced six projects that aim to find ways of convert captured carbon dioxide (CO2) emissions from industrial sources into useful products. The innovative projects -...

179

Method of converting an existing vehicle powertrain to a hybrid ...  

A method of converting an existing vehicle powertrain including a manual transmission to a hybrid powertrain system with an automated powertrain transmission. The ...

180

Design and Testing of a Thermoacoustic Power Converter .  

E-Print Network (OSTI)

??Thermoacoustic engines convert heat into acoustic pressure waves with no moving parts; this inherently results in high reliability, low maintenance and low manufacturing costs. Significant… (more)

Telesz, Mark P.

2006-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "loss torque converter" 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

Ultracold neutron accumulation in a superfluid-helium converter with magnetic multipole reflector  

E-Print Network (OSTI)

We analyze accumulation of ultracold neutrons (UCN) in a superfluid-helium converter vessel surrounded by a magnetic multipole reflector. Employing formulas valid for trapped UCN in mechanical equilibrium we solved the rate equation and obtained results for the saturation density of low field seeking UCN for any field strength of the multipolar field. The addition of magnetic storage can increase the density and energy of the UCN produced and serves to mitigate the effects of wall losses on the source performance. This work was performed in preparation of the UCN source project SuperSUN at the ILL.

O. Zimmer; R. Golub

2013-03-08T23:59:59.000Z

182

Light-induced torque for the generation of persistent current flow in atomic gas Bose-Einstein condensates  

SciTech Connect

We show that a persistent current flow in an atomic gas Bose-Einstein condensate could be realized when the system is subject to two counterpropagating Laguerre-Gaussian so-called doughnut beams, creating a toroidal trap. The theory is developed involving a two-photon process within three atomic levels leading to a quantized light-induced torque which rotates the atoms, generating an atomic current flow in the ring. We also show that it is possible for the torque to be controlled and even switched on and off by varying the frequencies of the incident light, thereby allowing a mechanism for the control of the current flow.

Lembessis, V. E. [New York College, 38 Amalias Avenue, GR-105 58, Athens (Greece); Babiker, M. [Department of Physics, University of York, York YO10 5DD (United Kingdom)

2010-11-15T23:59:59.000Z

183

Converting sensitive waste into cleaner energy  

DOE Green Energy (OSTI)

The destruction of sensitive unclassified information (SUI) has always been expensive due to the need for special controls to ensure its protection from disclosure to unauthorized persons. The sensitive documents were shredded, buried at the landfill, or sent to a recycling company. The Department of Energy (DOE) Idaho National Engineering and Environmental Laboratory (INEEL), operated by Lockheed Martin Idaho Technologies Company (LMITCO), has created an innovative method to dispose of its sensitive unclassified paper waste which has security, economic, and environmental benefits. A new cubing facility at the INEEL converts office and industrial waste into compact cubes which are then combined with coal and burned as a source of heat and process steam to run the Idaho Chemical Processing Plant (ICPP) facility. The process-engineered fuel, consisting of 25% cubes and 75% coal, bums cleaner than coal with lower emissions of sulfur dioxide and nitrogen oxides. The alternative fuel also reduces fuel costs, eliminates paying a recycling company, reduces the expense of landfill disposal, increases the life of the landfill, and provides energy to operate a large facility. The Operations Security (OPSEC) team capitalized on this waste to energy technology by recommending that the large quantities of sensitive information (documents) generated at the INEEL be disposed of in this manner. In addition to the economic and environmental benefits, this disposal method minimizes the vulnerabilities of SUI from disclosure to unauthorized personnel. The {open_quotes}cuber{close_quotes} technology has potential application in government and industry for protection of SUI.

Schriner, D.; Skinner, R.

1997-10-01T23:59:59.000Z

184

Motor torque compensation of an induction electric motor by adjusting a slip command during periods of supposed change in motor temperature  

SciTech Connect

The present invention maintains constant torque in an inverter driven AC induction motor during variations in rotor temperature. It is known that the torque output of a given AC induction motor is dependent upon rotor temperature. At rotor temperatures higher than the nominal operating condition the rotor impedance increases, reducing the rotor current and motor torque. In a similar fashion, the rotor impedance is reduced resulting in increased rotor current and motor torque when the rotor temperature is lower than the nominal operating condition. The present invention monitors the bus current from the DC supply to the inverter and adjusts the slip frequency of the inverter drive to maintain a constant motor torque. This adjustment is based upon whether predetermined conditions implying increased rotor temperature or decreased rotor temperature exist for longer that a predetermined interval of time.

Kelledes, William L. (Brighton, MI); St. John, Don K. (Livonia, MI)

1992-01-01T23:59:59.000Z

185

Optimal Driving Force for Converting Excitons into Free Carriers in Excitonic Solar Cells  

DOE Green Energy (OSTI)

A general but limiting characteristic in excitonic photovoltaics is that a portion of the incident photon energy appears necessary for converting excitons into electrical charges, resulting in a loss of efficiency. Currently, the mechanism underlying this process is unclear. Here, we describe the development of an experimental method for measuring charge creation yields in organic solar cell materials. We use this method to examine a series of conjugated polymer:fullerene blend films and observe two unexpected features: the existence of an optimal driving force and a loss in conversion efficiency if this force is exceeded. These observations have implications for the design of excitonic photovoltaic devices and can be explained by a simple Marcus formulation that introduces the importance of reorganization energy.

Coffey, D. C.; Larson, B. W.; Hains, A. W.; Whitaker, J. B.; Kopidakis, N.; Boltalina, O. V.; Strauss, S. H.; Rumbles, G.

2012-04-26T23:59:59.000Z

186

Ocean tide energy converter having improved efficiency  

Science Conference Proceedings (OSTI)

A tide motor useful for converting periodic rising and falling water levels to useful work such as electric power generation includes a primary piston having a large enclosed chamber that can selectively be filled with air for generation of upward thrust when submerged in rising tidal water or filled with water for generating downward gravitational thrust when the piston is suspended in air above a dropping tidal water level. Cyclic filling and emptying of the chamber is programmed to coordinate piston positions and water level positions, and the piston can be locked in either up or down position to achieve maximum flotation and gravitational thrust forces. An auxiliary tidal piston that can be locked in a down position has an upper water chamber provided with flood valves and an air filled, sealed flotation chamber below. The auxiliary piston is located near the primary piston, and is designed to have positive buoyancy when its respective chambers are filled with water and air. The lower area of the water chamber of the auxiliary piston is connected to the lower area of the primary piston chamber by a valve conduit so the primary piston chamber can be filled with water at its high position while it is locked up by releasing the auxiliary piston to float upwardly with its water chamber filled, and placing the primary and auxiliary piston chambers in communication with each other so water flows from the latter into the former until the primary piston chamber is filled with water before it begins its downward stroke after the water level has dropped below it. After the primary piston has completed its downward stroke, its interior chamber is drained and sealed in preparation for its next upward stroke on the next rising tide, and the water chamber of the auxiliary piston is refilled in preparation for the next cycle of operation.

Rainey, D.E.

1980-01-29T23:59:59.000Z

187

Converting hard copy documents for electronic dissemination  

SciTech Connect

Since the advent of computer systems, the goal of a paperless office, and even a paperless society, has been pursued. While the normal paper flow in an organization is far from totally automated, particularly for items requiring signatures or authorizations, electronic information dissemination is becoming an almost simple task. The reasons for providing on-line documents are many and include faster and easier access for everyone, elimination of printing costs, reduction of wasted shelf and desk space, and the security of having a centrally-located, always up-to-date document. New computer software even provides the user with the ability to annotate documents and to have bookmarks so that the old scribbled-in and dog-eared manual can be replaced without loosing this `customizability`. Moreover, new hypermedia capabilities mean that documents can be read in a non-linear fashion and can include color figures and photographs, audio, and even animation sequences, capabilities which exceed those of paper. The proliferation of network-based information servers, coupled with the growth of the Internet, has enticed academic, governmental, and even commercial organizations to provide increasing numbers of documents and data bases in electronic form via the network, not just to internal staff, but to the public as well. Much of this information, which includes everything from mundane company procedures to spiffy marketing brochures, was previously published only in hard copy. Converting existing documents to electronic form and producing only electronic versions of new documents poses some interesting challenges to the maintainer or author.

Hoffman, F.

1994-12-31T23:59:59.000Z

188

Radio Interference From HVDC Converter Stations, Modeling and Characterization  

Science Conference Proceedings (OSTI)

High-voltage direct-current converter stations generate electromagnetic interference (EMI) that can affect the performance of nearby electronic equipment. A prototype computer program that calculates EMI characteristics in the 5-500-kHz range will enable utility engineers to determine the extent of such interference during the design stage of a converter station.

1986-12-16T23:59:59.000Z

189

Adaptive decentralised control of parallel DC-DC converter systems  

Science Conference Proceedings (OSTI)

In this paper, we develop a robust controller for parallel DC-DC converter system by combining the adaptive backstepping technique and decentralised control. The voltages and currents of all converters are coupled with each other. The parallel DC-DC ...

Jing Zhou

2012-08-01T23:59:59.000Z

190

Learning/teaching graphical user interface based power electronic converters  

Science Conference Proceedings (OSTI)

This paper presents an intuitive graphical user interface for simulation of various topologies of power electronic converters. The simulator is developed using the GUIDE tool of MATLAB®, which acts as a front-end interface that can be ... Keywords: MATLAB®/SIMULINK®, converter design, power electronics teaching tool

S. Doolla; T. S. Bhatti

2006-01-01T23:59:59.000Z

191

The frequency dependent impedance of an HVdc converter  

Science Conference Proceedings (OSTI)

A linear and direct method of determining the frequency dependent impedance of a 12 pulse HVdc converter is presented. Terms are developed for both the dc and ac side impedances of the converter, including the effect of the firing angle control system, the commutation period, and the variability of the commutation period. The impedance predictions are verified by dynamic simulation.

Wood, A.R.; Arrillaga, J. [Univ. of Canterbury, Christchurch (New Zealand)

1995-07-01T23:59:59.000Z

192

Magnet Technology for Power Converters: Nanocomposite Magnet Technology for High Frequency MW-Scale Power Converters  

Science Conference Proceedings (OSTI)

Solar ADEPT Project: CMU is developing a new nanoscale magnetic material that will reduce the size, weight, and cost of utility-scale PV solar power conversion systems that connect directly to the grid. Power converters are required to turn the energy that solar power systems create into useable energy for the grid. The power conversion systems made with CMU’s nanoscale magnetic material have the potential to be 150 times lighter and significantly smaller than conventional power conversion systems that produce similar amounts of power.

None

2012-02-27T23:59:59.000Z

193

MHK Technologies/The DEXAWAVE wave energy converter | Open Energy  

Open Energy Info (EERE)

DEXAWAVE wave energy converter DEXAWAVE wave energy converter < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage The DEXAWAVE wave energy converter.jpg Technology Profile Primary Organization Dexawave Technology Readiness Level Click here TRL 7 8 Open Water System Testing Demonstration and Operation Technology Description The DEXAWAVE wave energy converter has a simple construction It consists of two rigid pontoons hinged together using a patented hinge The one pontoon can pivot relative to the other There is a hydraulic power take off system on top of the converter generating up to 250 kW Technology Dimensions Technology Nameplate Capacity (MW) 25 Device Testing Scale Test *At present our 1 to 5 scale model is working the waters outside the Danish port of Hanstholm collecting valuable data about the waves and currents that are constantly pounding the structure

194

State Energy Program Helping Arkansans Convert to Compressed Natural Gas |  

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

State Energy Program Helping Arkansans Convert to Compressed State Energy Program Helping Arkansans Convert to Compressed Natural Gas State Energy Program Helping Arkansans Convert to Compressed Natural Gas January 25, 2012 - 4:30pm Addthis The Arkansas Energy Office recently launched a Compressed Natural Gas Conversion Rebate Program, which provides incentives for fleets and individuals to purchase and/or convert their Arkansas-licensed vehicles to compressed natural gas (CNG). | All Rights Reserved. The Arkansas Energy Office recently launched a Compressed Natural Gas Conversion Rebate Program, which provides incentives for fleets and individuals to purchase and/or convert their Arkansas-licensed vehicles to compressed natural gas (CNG). | All Rights Reserved. Grayson Bryant Project Officer -- State Energy Program

195

MHK Technologies/Magnetohydrodynamic MHD Wave Energy Converter MWEC | Open  

Open Energy Info (EERE)

Magnetohydrodynamic MHD Wave Energy Converter MWEC Magnetohydrodynamic MHD Wave Energy Converter MWEC < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage Magnetohydrodynamic MHD Wave Energy Converter MWEC.jpg Technology Profile Primary Organization Scientific Applications Research Associates Inc SARA Technology Resource Click here Wave Technology Type Click here Point Absorber - Submerged Technology Readiness Level Click here TRL 5 6 System Integration and Technology Laboratory Demonstration Technology Description The Magnetohydrodynamic MHD Wave Energy Converter couples the up down motion of heave based systems A shaft transfers wave motion to the MHD generator which is deep underwater The shaft forces the conducting fluid through a set of powerful permanent magnets creating a low voltage high current electrical energy An electrical inverter converts the electrical energy to commercial quality 60 Hz AC power

196

A computer program for HVDC converter station RF noise calculations  

SciTech Connect

HVDC converter station operations generate radio frequency (RF) electromagnetic (EM) noise which could interfere with adjacent communication and computer equipment, and carrier system operations. A generic Radio Frequency Computer Analysis Program (RAFCAP) for calculating the EM noise generated by valve ignition of a converter station has been developed as part of a larger project. The program calculates RF voltages, currents, complex power, ground level electric field strength and magnetic flux density in and around an HVDC converter station. The program requires the converter station network to be represented by frequency dependent impedance functions. Comparisons of calculated and measured values are given for an actual HVDC station to illustrate the validity of the program. RAFCAP is designed to be used by engineers for the purpose of calculating the RF noise produced by the igniting of HVDC converter valves.

Kasten, D.G.; Caldecott, R.; Sebo, S.A. (Ohio State Univ., Columbus, OH (United States). Dept. of Electrical Engineering); Liu, Y. (Virginia Polytechnic Inst. State Univ., Blacksburg, VA (United States). Bradley Dept. of Electrical Engineering)

1994-04-01T23:59:59.000Z

197

A study of Schwarz converters for nuclear powered spacecraft  

DOE Green Energy (OSTI)

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

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

1994-09-01T23:59:59.000Z

198

Low torque hydrodynamic lip geometry for bi-directional rotation seals  

DOE Patents (OSTI)

A hydrodynamically lubricating geometry for the generally circular dynamic sealing lip of rotary seals that are employed to partition a lubricant from an environment. The dynamic sealing lip is provided for establishing compressed sealing engagement with a relatively rotatable surface, and for wedging a film of lubricating fluid into the interface between the dynamic sealing lip and the relatively rotatable surface in response to relative rotation that may occur in the clockwise or the counter-clockwise direction. A wave form incorporating an elongated dimple provides the gradual convergence, efficient impingement angle, and gradual interfacial contact pressure rise that are conducive to efficient hydrodynamic wedging. Skewed elevated contact pressure zones produced by compression edge effects provide for controlled lubricant movement within the dynamic sealing interface between the seal and the relatively rotatable surface, producing enhanced lubrication and low running torque.

Dietle, Lannie L. (Houston, TX); Schroeder, John E. (Richmond, TX)

2011-11-15T23:59:59.000Z

199

Low torque hydrodynamic lip geometry for bi-directional rotation seals  

DOE Patents (OSTI)

A hydrodynamically lubricating geometry for the generally circular dynamic sealing lip of rotary seals that are employed to partition a lubricant from an environment. The dynamic sealing lip is provided for establishing compressed sealing engagement with a relatively rotatable surface, and for wedging a film of lubricating fluid into the interface between the dynamic sealing lip and the relatively rotatable surface in response to relative rotation that may occur in the clockwise or the counter-clockwise direction. A wave form incorporating an elongated dimple provides the gradual convergence, efficient impingement angle, and gradual interfacial contact pressure rise that are conducive to efficient hydrodynamic wedging. Skewed elevated contact pressure zones produced by compression edge effects provide for controlled lubricant movement within the dynamic sealing interface between the seal and the relatively rotatable surface, producing enhanced lubrication and low running torque.

Dietle, Lannie L. (Houston, TX); Schroeder, John E. (Richmond, TX)

2009-07-21T23:59:59.000Z

200

Direct Torque Control Based on Space Vector Modulation with Adaptive Neural Integrator for Stator Flux Estimation in Induction Motors  

Science Conference Proceedings (OSTI)

Direct torque control based on space vector modulation (SVM-DTC) preserve DTC transient merits, furthermore, produce better quality steady-state performance in a wide speed range. A new adaptive neural integration algorithm for estimating stator flux ... Keywords: DTC, space vector modulation, adaptive neural integrator, stator flux estimation

Chunhua Zang; Xianqing Cao

2009-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "loss torque converter" 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

ngineering mechanics is the engineering science that deals with the effects of forces and torques on particles, rigid bod-  

E-Print Network (OSTI)

E ngineering mechanics is the engineering science that deals with the effects of forces and torques on particles, rigid bod- ies, or deformable media. Mechanics is typically subdivided into statics, dynamics, and mechanics of deformable bodies. Statics considers the algebra of vectors, equilibrium, equiva- lency

Demirel, Melik C.

202

436 IEEE/ASME TRANSACTIONS ON MECHATRONICS, VOL. 9, NO. 2, JUNE 2004 Torque and Velocity Ripple Elimination of AC  

E-Print Network (OSTI)

Elimination of AC Permanent Magnet Motor Control Systems Using the Internal Model Principle Wai-Chuen Gan and velocity ripple elimination in AC permanent magnet (PM) motor control systems. The torque ripples caused-free output response. Index Terms--AC permanent magnet motor, gain scheduled (GS) speed regulators, internal

Qiu, Li

203

Influence of Rotor Structure and Number of Phases on Torque and Flux Weakening Characteristics of V-shape Interior PM  

E-Print Network (OSTI)

on torque and Flux weakening region of V-shape IPM machine from TOYOTA PRIUS type, more specifically number on the machine characteristics, PRIUS structure is transformed into 5-phase machine of the same which have the same type and dimensions of TOYOTA PRIUS machine [6], but they differ in the phase number

Paris-Sud XI, Université de

204

Why Western Boundary Currents in Realistic Oceans are Inviscid: A Link between Form Stress and Bottom Pressure Torques  

Science Conference Proceedings (OSTI)

It is shown that wind stress curl is balanced by bottom pressure torque in a zonal integral over any strip wide enough to smooth out the effect of nonlinear terms (typically about 3° of latitude). The derivation is completely general as long as ...

Chris W. Hughes; Beverly A. de Cuevas

2001-10-01T23:59:59.000Z

205

Department of Mechanical and Nuclear Engineering Fall 2011 Torque and Axial Measurement Device for Soil Abrasion Testing  

E-Print Network (OSTI)

PENNSTATE Department of Mechanical and Nuclear Engineering Fall 2011 Torque and Axial Measurement Device for Soil Abrasion Testing Overview The Penn State Department of Energy and Mineral Engineering to completely re-design with five weeks left. This left minimal time for machining, assembly, testing

Demirel, Melik C.

206

Improved braking torque generation capacity of an eddy current brake with time varying magnetic fields: A numerical study  

Science Conference Proceedings (OSTI)

Eddy current brakes (ECB) are electrically controlled and non-contact actuators used as assistive brakes in vehicles. ECBs exhibit insufficient generated braking torque at low speeds. In order to overcome this, the use of AC magnetic fields with fixed ... Keywords: Automotive applications, Brake-by-wire, Eddy current brakes, Finite element analysis, Time-varying magnetic field

Kerem Karakoc; Edward J. Park; Afzal Suleman

2012-10-01T23:59:59.000Z

207

PERFORMANCE AND ENERGY-TRANSFER MEASUREMENTS ON CYLINDRICAL CESIUM THERMIONIC CONVERTERS  

SciTech Connect

Detailed measurements of performance and energy transfer were made on two highly instrumented cylindrical cesium thermionic converters with electrically heated tungsten emitters. The first converter, OC-4, which had a niobium collector, operated with an initial electrical output of 6.9 watts/cm/sup 2/. This output gradually degraded to a value of 4.6 watts/cm/sup 2/ after 1351 hr. These power values were measured at the electrodes for an average emitter temperature of 1 750 deg C, Converter OC-5, which had a molybdenum collector, has operated 260 hr to date, with a power output and efficiency of 11.1 watts/cm/sup 2/ and 16%, respectively, at an average emitter temperature of 1800 deg C. These operating data are compared with those for lower emitter temperatures below. Temperature Density Efficiency Energy values of the emitter electron cooling, collector electron heating, thermal radiation, and cesium conduction were calorimetrically determined as a function of emitter temperature, collector temperature, cesium pressure, and current. For all the data obtained, the emitter temperature profile was measured by thermocouples. From the calorimeter measurements, correlations were found for the prediction of emitter electron cooling DELTA Q/sub E/ and collector electron heating DELTA Q/sub C/: DELTA Q/sub E/ = I (2.6 + V), and DELTA Q/sub C/ = I (2. The correlation is valid within 4% accuracy over the operating variable range: emitter temperature of 1200 to 1800 deg C; cesium reservoir temperature of 300 to 400 deg C;, collector temperature of 600 to 700 deg C; and current of zero to 15 amp/cm/sup 2/ . Through measurements of emitterstructure heat losses, of the cesium-vapor thermal conduction, and of the electrode radiation heat transfer, it was found that all the zero-current energy-transfer quantities can be accurately predicted with RAT, a two-dimensional digital-computer heat-transfer code. The electron cooling correlation, together with the ability to calculate all of the power-loss values in a thermionic converter, makes it possible to compute the efficiency of a converter when the I-V characteristics and materials properties are known This is of special interest to thermionic reactor analysis, since the input to the reactor problem is the amount of fission produced in each of a very large number of cells within the reactor. Apart from the utility of the correlation discovered, the determination of the value of 2.6 volts in the current-heating terms is of fundamental interest and invites further study. (auth)

Holland, J.W.

1963-11-13T23:59:59.000Z

208

A 1 MEGAWATT POLYPHASE BOOST CONVERTER-MODULATOR FOR KLYSTRON PULSE APPLICATION  

SciTech Connect

This paper describes electrical design criteria and first operational results a 140 kV, 1 MW average, 11 MW peak, zero-voltage-switching 20 kHz polyphase bridge, boost converter/modulator for klystron pulse application. The DC-DC converter derives the buss voltages from a standard 13.8 kV to 2300 Y substation cast-core transformer. Energy storage and filtering is provided by self-clearing metallized hazy polypropylene traction capacitors. Three ''H-Bridge'' Insulated Gate Bipolar Transistor (IGBT) switching networks are used to generate the polyphase 20 kHz transformer primary drive waveforms. The 20 kHz drive waveforms are chirped the appropriate duration to generate the desired klystron pulse width. PWM (pulse width modulation) of the individual 20 kHz pulses is utilized to provide regulated output waveforms with adaptive feedforward and feedback techniques. The boost transformer design utilizes amorphous nanocrystalline material that provides the required low core loss at design flux levels and switching frequencies. Resonant shunt-peaking is used on the transformer secondary to boost output voltage and resonate transformer leakage inductance. With the appropriate transformer leakage inductance and peaking capacitance, zero-voltage-switching of the IGBT's is attained, minimizing switching losses. A review of these design parameters and the first results of the performance characteristics will be presented.

W.A. REASS; J.D. DOSS; R.F. GRIBBLE

2001-06-01T23:59:59.000Z

209

Design, status and first operations of the spallation neutron source polyphase resonant converter modulator system  

DOE Green Energy (OSTI)

The Spallation Neutron Source (SNS) is a new 1.4 MW average power beam, 1 GeV accelerator being built at Oak Ridge National Laboratory. The accelerator requires 15 converter-modulator stations each providing between 9 and 11 MW pulses with up to a 1 .I MW average power. The converter-modulator can be described as a resonant 20 kHz polyphase boost inverter. Each converter modulator derives its buss voltage from a standard substation cast-core transformer. Each substation is followed by an SCR pre-regulator to accommodate voltage changes from no load to full load, in addition to providing a soft-start function. Energy storage is provided by self-clearing metallized hazy polypropylene traction capacitors. These capacitors do not fail short, but clear any internal anomaly. Three 'H-Bridge' IGBT transistor networks are used to generate the polyphase 20 kHz transformer primary drive waveforms. The 20 kHz drive waveforms are time-gated to generate the desired klystron pulse width. Pulse width modulation of the individual 20 lcHz pulses is utilized to provide regulated output waveforms with DSP based adaptive feedforward and feedback techniques. The boost transformer design utilizes nanocrystalline alloy that provides low core loss at design flux levels and switching frequencies. Capacitors are used on the transformer secondary networks to resonate the leakage inductance. The transformers are wound for a specific leakage inductance, not turns ratio. This design technique generates multiple secondary volts per turn as compared to the primary. With the appropriate tuning conditions, switching losses are minimized. The resonant topology has the added benefit of being deQed in a klystron fault condition, with little energy deposited in the arc. This obviates the need of crowbars or other related networks. A review of these design parameters, operational performance, production status, and OWL installation and performance to date will be presented.

Reass, W. A. (William A.); Apgar, S. E. (Sean E.); Baca, D. M. (David M.); Doss, James D.; Gonzales, J. (Jacqueline); Gribble, R. F. (Robert F.); Hardek, T. W. (Thomas W.); Lynch, M. T. (Michael T.); Rees, D. E. (Daniel E.); Tallerico, P. J. (Paul J.); Trujillo, P. B. (Pete B.); Anderson, D. E. (David E.); Heidenreich, D. A. (Dale A.); Hicks, J. D. (Jim D.); Leontiev, V. N.

2003-01-01T23:59:59.000Z

210

Gas Water Heater Energy Losses  

E-Print Network (OSTI)

non-firing, non- recovery mode, i.e. , during standby mode.The stack losses while in standby mode account for about 43%can be made by reducing standby heat losses. This paper

Biermayer, Peter

2012-01-01T23:59:59.000Z

211

Universal Converter Using SiC  

SciTech Connect

The grantee designed a high power (over 1MW) inverter for use in renewable and distributed energy systems, such as PV cells, fuel cells, variable speed wind turbines, micro turbines, variable speed gensets and various energy storage methods. The inverter uses 10,000V SiC power devices which enable the use of a straight-forward topology for medium voltage (4,160VAC) without the need to cascade devices or topologies as is done in all commercial, 4,160VAC inverters today. The use of medium voltage reduces the current by nearly an order of magnitude in all current carrying components of the energy system, thus reducing size and cost. The use of SiC not only enables medium voltage, but also the use of higher temperatures and switching frequencies, further reducing size and cost. In this project, the grantee addressed several technical issues that stand in the way of success. The two primary issues addressed are the determination of real heat losses in candidate SiC devices at elevated temperature and the development of high temperature packaging for SiC devices.

Dallas Marckx; Brian Ratliff; Amit Jain; Matthew Jones

2007-01-01T23:59:59.000Z

212

Louisiana Wetland Loss at Askives  

U.S. Energy Information Administration (EIA)

Louisiana Wetland Loss? - Find Questions and Answers at Askives, the first startup that gives you an straight answer

213

Fission converter heat removal and safety under accident conditions  

Science Conference Proceedings (OSTI)

The design and safety of the heat removal system of the Massachusetts Institute of Technology (MIT) design for a fission converter-based epithermal beam is discussed in this paper. Plate-type reactor fuel elements, used in the MIT research reactor (MITR-II), are also used for the fission converter. This fission converter-based beam provides epithermal neutron fluxes at the patient position in excess of 10{sup 10} n/cm{sup 2}s with very low contamination of fast neutrons and gamma rays.

Sutharshan, B.; Todreas, N.E.; Harling, O.K. [Massachusetts Inst. of Technology, Cambridge, MA (United States)

1996-12-31T23:59:59.000Z

214

Prediction of core saturation instability at an HVDC converter  

SciTech Connect

Core saturation instability has occurred on several HVDC schemes resulting from interactions between second harmonic and dc quantities (voltages and currents) on the ac side of the converter and fundamental frequency quantities on the dc side of the converter. The instability can be reinforced by unbalanced saturation of the converter transformers. The paper presents an analytical method which can be used to quickly screen ac and dc system operating conditions to predict where core saturation instability is likely to occur. Analytical results have been confirmed using the digital transients simulation program PSCAD/EMTDC.

Burton, R.S. [Teshmont Consultants, Inc., Winnipeg, Manitoba (Canada); Fuchshuber, C.F. [Alberta Power Ltd., Edmonton, Alberta (Canada); Woodford, D.A. [Manitoba HVDC Research Centre, Winnipeg, Manitoba (Canada); Gole, A.M. [Univ. of Manitoba, Winnipeg, Manitoba (Canada)

1996-10-01T23:59:59.000Z

215

A prototype ASIC buck converter for LHC upgrades  

E-Print Network (OSTI)

Given the larger number of channels and the need for reduced material budget in the SLHC trackers, alternatives to the present power distribution scheme have to be explored. In this context we are envisaging a new architecture based on custom switching converters able to work in the high radiation and high magnetic field environment of the experiments. A prototype converter has been designed and integrated in an ASIC. This includes the fundamental building blocks of a buck converter that can be used in later and more complete designs and even in different topologies. Design techniques and functional tests of the prototype will be discussed.

Michelis, S; Allongue, B; Blanchot, G; Fuentes, C; Kayal, M

2008-01-01T23:59:59.000Z

216

MHK Technologies/Tunneled Wave Energy Converter TWEC | Open Energy  

Open Energy Info (EERE)

Tunneled Wave Energy Converter TWEC Tunneled Wave Energy Converter TWEC < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage Tunneled Wave Energy Converter TWEC.jpg Technology Profile Primary Organization SeWave Ltd Project(s) where this technology is utilized *MHK Projects/TWEC Project Technology Resource Click here Wave Technology Type Click here Oscillating Water Column Technology Readiness Level Click here TRL 1-3: Discovery / Concept Definition / Early Stage Development & Design & Engineering Technology Description The Tunneled Wave Energy Converter TWEC utilizes the OWC principle through its use of a proposed bored out tunnel within a cliff side of the Faroe Islands Technology Dimensions Device Testing Date Submitted 10/8/2010 << Return to the MHK database homepage

217

Converting DOE Technical Standards to Voluntary Consensus Standards...  

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

DOE-TSPP-8-2013 DOE TECHNICAL STANDARDS September 2013 PROGRAM PROCEDURES CONVERTING DOE TECHNICAL STANDARDS TO VOLUNTARY CONSENSUS STANDARDS U.S. Department of Energy Office of...

218

Converting Unconditioned Garage to Conditioned Space - Code Notes |  

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

Converting Unconditioned Garage to Conditioned Space - Code Notes Converting Unconditioned Garage to Conditioned Space - Code Notes Converting an existing unconditioned garage to conditioned space is a popular strategy for increasing the living space of a house. Typically, the conversion or remodeling must be done in compliance with construction codes in force at the time the remodel permit is issued. Compliance shall be demonstrated by meeting the requirements of the 2009 International Energy Conservation Code. Publication Date: Thursday, December 15, 2011 cn_converting_unconditioned_garage_to_conditioned_space.pdf Document Details Document Number: PNNL-SA-83069 Prepared by: Pacific Northwest National Laboratory for the U.S. Department of Energy Building Energy Codes Program Focus: Compliance Building Type: Residential

219

Enterprise converting buses to biodiesel | Department of Energy  

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

Enterprise converting buses to biodiesel Enterprise converting buses to biodiesel Enterprise converting buses to biodiesel April 1, 2010 - 6:48pm Addthis Paul Lester Communications Specialist, Office of Energy Efficiency and Renewable Energy Rental car customers may be able to breathe a little easier during their next trip to the airport. Alamo Rent A Car, Enterprise Rent-A-Car, and National Car Rental, all brands operated by the subsidiaries of Enterprise Holdings, are converting their airport shuttle buses to run on biodiesel fuel. The move is a good one for the environment, and will ultimately reduce the company's carbon emissions. "We are saving 420,000 gallons of petroleum diesel," says Lee Broughton, director of corporate identity and sustainability for Enterprise Holdings. Hydrocarbon and particulate matter emissions will plummet, making the air

220

MHK Technologies/The Crestwing Wave Energy Converter | Open Energy  

Open Energy Info (EERE)

Crestwing Wave Energy Converter Crestwing Wave Energy Converter < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage The Crestwing Wave Energy Converter.jpg Technology Profile Primary Organization Waveenergyfyn Technology Resource Click here Wave Technology Type Click here Attenuator Technology Readiness Level Click here TRL 7 8 Open Water System Testing Demonstration and Operation Technology Description The connected pontoons swing around the hinge when the top of the waves passes under the floats The pontoons relative motion is converted into usable energy through a linear PTO system The pontoons are pushed upwards from the below passing wave and again dragged down by the same passing wave Complex hydrodynamic conditions occur under the pontoons when the wave formation pushes the unit up and down simultaneously The energy from waves can be divided into fifty percent potential energy and fifty percent kinetic energy Crestwing absorbs both the potential energy as the kinetic energy which is the back ground for the high efficiency

Note: This page contains sample records for the topic "loss torque converter" 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

Implementation of control system for hydrokinetic energy converter  

Science Conference Proceedings (OSTI)

At Uppsala University, a research group is investigating a system for converting the power in freely flowing water using a verticalaxis turbine directly connected to a permanent magnet generator. An experimental setup comprising a turbine, a generator, ...

Katarina Yuen, Senad Apelfröjd, Mats Leijon

2013-01-01T23:59:59.000Z

222

Monolithic series-connected gallium arsenide converter development  

DOE Green Energy (OSTI)

We report the development of monolithic GaAs photovoltaic devices intended to convert light generated by a laser or other bright source to electricity. The converters described here can provide higher operating voltage than is possible using a single-junction converter, owing to use of a monolithic circuit that forms a planar series-connected string of single-junction sub-cells. This planar monolithic circuit is arranged to deliver the desired voltage and current during operation at the maximum power point. The paper describes two-, six-, and twelve-junction converters intended for illumination by a laser diode with a wavelength of 0.8 {mu}m. Design and characterization data are presented for optical power in the range of 100 mW to 1 W. The best conversion efficiency exceeds 50%. 9 refs., 4 figs., 2 tabs.

Spitzer, M.B.; McClelland, R.W.; Dingle, B.D.; Dingle, J.E.; Hill, D.S. (Kopin Corp., Taunton, MA (United States)); Rose, B.H. (Sandia National Labs., Albuquerque, NM (United States))

1991-01-01T23:59:59.000Z

223

10-MW GTO converter for battery peaking service  

SciTech Connect

A bidirectional 18-pulse voltage source converter utilizing gate turn-off thyristors (GTO's) is described. The converter, which is rated 10 MVA, was placed in service in early 1988 to connect an energy storage battery to a utility grid. The converter is rated and controlled to operate in all four quadrants (discharge, charge, leading vars, or lagging vars) at the full 10-MVA rating. It is capable of independent rapid control of real and reactive power with a transient response of 16 ms to changes in commanded value of real or reactive power. Thus it is usable as a reactive power controller (static var control), voltage control, frequency control, power system stabilizer, or as a real power peaking station. For use as a reactive power controller only, no battery would be needed. The design, construction, control, and application of the converter are described, and performance data taken at factory power test and at the installation are given.

Walker, L.H. (Drive Development Engineering, Drive Systems, General Electric Co., Salem, VA (US))

1990-01-01T23:59:59.000Z

224

Method for converting uranium oxides to uranium metal  

DOE Green Energy (OSTI)

A process is described for converting scrap and waste uranium oxide to uranium metal. The uranium oxide is sequentially reduced with a suitable reducing agent to a mixture of uranium metal and oxide products. The uranium metal is then converted to uranium hydride and the uranium hydride-containing mixture is then cooled to a temperature less than -100.degree. C. in an inert liquid which renders the uranium hydride ferromagnetic. The uranium hydride is then magnetically separated from the cooled mixture. The separated uranium hydride is readily converted to uranium metal by heating in an inert atmosphere. This process is environmentally acceptable and eliminates the use of hydrogen fluoride as well as the explosive conditions encountered in the previously employed bomb-reduction processes utilized for converting uranium oxides to uranium metal.

Duerksen, Walter K. (Norris, TN)

1988-01-01T23:59:59.000Z

225

step 1: retrieve usage step 2: convert usage  

E-Print Network (OSTI)

planet #12;step 2: convert usage data to ghg electricity conversion EPA eGRID database provides state by state data on: lbs CO2 / MWh lbs NOx / MWH eGRID Massachusetts ­ specific conversion factors only

Paulsson, Johan

226

Method for converting uranium oxides to uranium metal  

DOE Patents (OSTI)

A process is described for converting scrap and waste uranium oxide to uranium metal. The uranium oxide is sequentially reduced with a suitable reducing agent to a mixture of uranium metal and oxide products. The uranium metal is then converted to uranium hydride and the uranium hydride-containing mixtures is then cooled to a temperature less than -100/sup 0/C in an inert liquid which renders the uranium hydride ferromagnetic. The uranium hydride is then magnetically separated from the cooled mixture. The separated uranium hydride is readily converted to uranium metal by heating in an inert atmosphere. This process is environmentally acceptable and eliminates the use of hydrogen fluoride as well as the explosive conditions encountered in the previously employed bomb-reduction processes utilized for converting uranium oxides to uranium metal.

Duerksen, W.K.

1987-01-01T23:59:59.000Z

227

California's program converts biomass residues to energy  

SciTech Connect

This paper provides a brief introduction to the emerging biomass fuel industry in California and includes descriptions of California's biomass potential, California's biomass development program, and legislation that expands the state's developmental efforts in biomass commercialization. California's agriculture and forest industries residues were discussed. These residues can be converted to energy, and now, through California's aggressive development program, more residues will be converted. (DP)

Ward, P.F.

1980-01-01T23:59:59.000Z

228

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

229

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

230

Efficiency and Loss Models for Key Electronic Components of Hybrid and Plug-in Hybrid Electric Vehicles' Electrical Propulsion Systems  

DOE Green Energy (OSTI)

Isolated gate bipolar transistors (IGBTs) are widely used in power electronic applications including electric, hybrid electric, and plug-in hybrid electric vehicles (EVs, HEVs, and PHEVs). The trend towards more electric vehicles (MEVs) has demanded the need for power electronic devices capable of handling power in the range of 10-100 kW. However, the converter losses in this power range are of critical importance. Therefore, thermal management of the power electronic devices/converters is crucial for the reliability and longevity of the advanced vehicles. To aid the design of heat exchangers for the IGBT modules used in propulsion motor drives, a loss model for the IGBTs is necessary. The loss model of the IGBTs will help in the process of developing new heat exchangers and advanced thermal interface materials by reducing cost and time. This paper deals with the detailed loss modeling of IGBTs for advanced electrical propulsion systems. An experimental based loss model is proposed. The proposed loss calculation method utilizes the experimental data to reconstruct the loss surface of the power electronic devices by means of curve fitting and linear extrapolating. This enables the calculation of thermal losses in different voltage, current, and temperature conditions of operation. To verify the calculation method, an experimental test set-up was designed and built. The experimental set-up is an IGBT based bi-directional DC/DC converter. In addition, simulation results are presented to verify the proposed calculation method.

Cao, J.; Bharathan, D.; Emadi, A.

2007-01-01T23:59:59.000Z

231

Low Impact Weight Loss Exercises | Fish Oil Weight Loss  

U.S. Energy Information Administration (EIA)

Low Impact Weight Loss Exercises. You want to lose weight, but for whatever reason, you want to or only can perform low impact exercises. No problem.

232

Application of wave generator theory to the development of a Wave Energy Converter  

E-Print Network (OSTI)

of the starting torque. To alleviate the self-starting problem, Gorlov [11] proposed a design of the three Reviews, Vol. 12, No. 4, pp. 1087-1109 (2008). [11] Gorlov, A. M., Unidirectional Helical Reaction Turbine

Wood, Stephen L.

233

Electromagnetic analysis of forces and torques on the baseline and enhanced ITER shield modules due to plasma disruption.  

SciTech Connect

An electromagnetic analysis is performed on the ITER shield modules under different plasma-disruption scenarios using the OPERA-3d software. The models considered include the baseline design as provided by the International Organization and an enhanced design that includes the more realistic geometrical features of a shield module. The modeling procedure is explained, electromagnetic torques are presented, and results of the modeling are discussed.

Kotulski, Joseph Daniel; Coats, Rebecca Sue; Pasik, Michael Francis; Ulrickson, Michael Andrew

2009-08-01T23:59:59.000Z

234

A new multi-motor drive system based on two-stage direct power converter.  

E-Print Network (OSTI)

??The two-stage AC to AC direct power converter is an alternative matrix converter topology, which offers the benefits of sinusoidal input currents and output voltages,… (more)

Kumar, Dinesh

2011-01-01T23:59:59.000Z

235

Modeling, Analysis and Stabilization of Converter-Dominated Power Distribution Grids.  

E-Print Network (OSTI)

??The energy sector is moving towards extensive use of power electronic (PE) converters to interface distributed generation (DG) units and modern converter-interfaced loads (CILs). Therefore,… (more)

Radwan, Amr A A

2012-01-01T23:59:59.000Z

236

MHK Technologies/Tide Current Converter | Open Energy Information  

Open Energy Info (EERE)

Tide Current Converter Tide Current Converter < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage Tide Current Converter.jpg Technology Profile Primary Organization Neptune Systems Technology Resource Click here Current Technology Type Click here Oscillating Wave Surge Converter Technology Readiness Level Click here TRL 1 3 Discovery Concept Def Early Stage Dev Design Engineering Technology Description The Tide Current Converter is based on the direct interaction between a magnetic electric and fluid flow field when a conductive fluid moves through a magnetic field electrical power is generated directly inside the fluid volume In this marine application the sea water itself is the conductive fluid A static antenna like structure generates the magnetic fields and at the same time taps the electrical power from the fluid current The configuration resembles a dynamo the sea water being the rotor and the antenna the stator The main advantage of the Magnetohydrodynamics MHD conversion is the absence of moving mechanical drive train components which make contemporary systems vulnerable and maintenance demanding

237

Progress in converting {sup 99}Mo production from high- to low-enriched uranium--1999.  

SciTech Connect

Over this past year, extraordinary progress has been made in executing our charter to assist in converting Mo-99 production worldwide from HEU to LEU. Building on the successful development of the experimental LEU-foil target, we have designed a new, economical irradiation target. We have also successfully demonstrated, in collaboration with BATAN in Indonesia, that LEU can be substituted for HEU in the Cintichem target without loss of product yield or purity; in fact, conversion may make economic sense. We are interacting with a number of commercial producers--we have begun active collaborations with the CNEA and ANSTO; we are working to define the scope of collaborations with MDS Nordion and Mallinckrodt; and IRE has offered its services to irradiate and test a target at the appropriate time. Conversion of the CNEA process is on schedule. Other papers presented at this meeting will present specific results on the demonstration of the LEU-modified Cintichem process, the development of the new target, and progress in converting the CNEA process.

Snelgrove, J. L.; Vandegrift, G. F.; Conner, C.; Wiencek, T. C.; Hofman, G. L.

1999-09-29T23:59:59.000Z

238

First results of the Los Alamos polyphase boost converter-modulator  

DOE Green Energy (OSTI)

This paper describes the first full-scale electrical test results of the Los Alamos polyphase boost converter-modulator being developed for the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory. The convertrr-modulator provides 140 kV, 1.2 mS, 60 Hz pulses to a 5 MW, 805 MHz klystron. The system, which has 1 MW average power, derives its +/- 1250 Volt DC buss link voltages from a standard 3-phase utility 13.8 kV to 2100 volt transformer. An SCR pre-regulator provides a soft-start function in addition to correction of line and load variations, from no-load to full-load. Energy storage is provided by low inductance self-clearing metallized hazy polypropylene traction capacitors. Each of the 3-phase H-bridge Insulated Gate Bipolar Transistor (IGBT) Pulse-Width Modulation (PWM) drivers are resonated with the amorphous nanocrystalline boost transformer and associated peaking circuits to provide zero-voltage-switching characteristics for the IGBT's. This design feature minimizes IGBT switching losses. By PWM of individual IGBT conduction angles, output pulse regulation with adaptive feedforward and feedback techniques is used to improve the klystron voltage pulse shape. In addition to the first operational results, this paper will discuss the relevant design techniques associated with the boost converter-modulator topology.

Doss, James D.; Gribble, R. F. (Robert F.); Lynch, M. T. (Michael T.); Rees, D. E. (Daniel E.); Tallerico, P. J. (Paul J.); Reass, W. A. (William A.)

2001-01-01T23:59:59.000Z

239

A high efficiency, soft switching dc-dc converter with adaptive current-ripple control for portable applications  

E-Print Network (OSTI)

Abstract—A novel control scheme for improving the power efficiency of low-voltage dc–dc converters for battery-powered, portable applications is presented. In such applications, light-load efficiency is crucial for extending battery life, since mobile devices operate in stand-by mode for most of the time. The proposed technique adaptively reduces the inductor current ripple with decreasing load current while soft switching the converter to also reduce switching losses, thereby significantly improving light-load efficiency and therefore extending the operation life of battery-powered devices. A load-dependent, mode-hopping strategy is employed to maintain high efficiency over a wide load range. Hysteretic (sliding-mode) control with user programmable hysteresis is implemented to adaptively regulate the current ripple and therefore optimize conduction and switching losses. Experimental results show that for a 1-A, 5- to 1.8-V buck regulator, the proposed technique achieved 5 % power efficiency improvement (from 72 % to 77%) at 100 mA of load current and a 1.5% improvement (from 84 % to 85.5%) at 300 mA, which constitute light-load efficiency improvements, when compared to the best reported, state-of-the-art techniques. As a result, the battery life in a typical digital signalr processing microprocessor application is improved by 7%, which demonstrates the effectiveness of the proposed solution. Index Terms—Battery life, buck converter, dc–dc converter, efficiency, hysteretic control, sliding-mode control, soft switching, switching regulator.

Siyuan Zhou; Student Member; Gabriel A. Rincón-mora; Senior Member

2006-01-01T23:59:59.000Z

240

Maryland Abuzz with Retrofit Converts | Department of Energy  

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

Abuzz with Retrofit Converts Abuzz with Retrofit Converts Maryland Abuzz with Retrofit Converts January 7, 2010 - 2:06pm Addthis Joshua DeLung Tim Kenny got a college degree in fisheries biology, but his real passion lies in something he's spent the last 20 years doing - helping American families in Maryland, Pennsylvania and Washington, D.C. He makes his living in the clean energy economy by finding ways people can save money on their energy bills and make their homes cleaner, safer and more comfortable. About four years ago, he started Housewarmers, a business that performs energy audits and weatherization work on the homes of everyday clientele. Tim also helps community action agencies complete weatherization work as a contractor through a separate nonprofit business, C&O Conservation, for

Note: This page contains sample records for the topic "loss torque converter" 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

NETL: News Release - Converting Emissions into Energy - Three Companies to  

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

September 14, 2000 September 14, 2000 Converting Emissions into Energy - Three Companies To Develop Technologies for Tapping Coal Mine Methane Methane, the chief constituent of natural gas, is a potent greenhouse gas, and millions of cubic feet of it escape daily from active coal mines. Now, three projects selected the U.S. Department of Energy propose new ways to capture the gas and convert it to useful energy -- reducing an environmental threat while adding to the nation's supplies of clean natural gas and electric power. The National Energy Technology Laboratory, the Energy Department's chief field site for its fossil energy research program, has selected: Appalachian-Pacific Coal Mine Methane Power Co., LLC, Arlington, VA, to work with West Virginia University Research Corp., Morgantown, WV, and Invitation Energy, Mannington, WV, to convert coal mine methane from mines in Marion County, WV, and surrounding areas into liquefied natural gas (LNG) to fuel heavy trucks.

242

MHK Technologies/Seatricity wave energy converter | Open Energy Information  

Open Energy Info (EERE)

Seatricity wave energy converter Seatricity wave energy converter < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage Seatricity wave energy converter.jpg Technology Profile Primary Organization Seatricity Project(s) where this technology is utilized *MHK Projects/Seatricity Antigua *MHK Projects/Seatricity Orkney Technology Resource Click here Wave Technology Type Click here Attenuator Technology Readiness Level Click here TRL 7/8: Open Water System Testing & Demonstration & Operation Technology Description In the simplest terms, a float travels up and down with the waves and operates a pump to pressurise sea water which is piped ashore. Many individual pumps are connected together to produce substantial amounts of pressurized water. Once ashore the pressurized sea water is used to drive a standard hydroelectric turbine to produce electricity.

243

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

244

Combustor design tool for a gas fired thermophotovoltaic energy converter  

DOE Green Energy (OSTI)

Recently, there has been a renewed interest in thermophotovoltaic (TPV) energy conversion. A TPV device converts radiant energy from a high temperature incandescent emitter directly into electricity by photovoltaic cells. The current Department of Energy sponsored research involves the design, construction and demonstration of a prototype TPV converter that uses a hydrocarbon fuel (such as natural gas) as the energy source. As the photovoltaic cells are designed to efficiently convert radiant energy at a prescribed wavelength, it is important that the temperature of the emitter be nearly constant over its entire surface. The US Naval Academy has been tasked with the development of a small emitter (with a high emissivity) that can be maintained at 1,756 K (2,700 F). This paper describes the computer spreadsheet model that was developed as a tool to be used for the design of the high temperature emitter.

Lindler, K.W.; Harper, M.J. [Naval Academy, Annapolis, MD (United States). Naval Architecture, Ocean and Marine Engineering Dept.

1995-07-01T23:59:59.000Z

245

Applications and benefits of catalytic converter thermal management  

DOE Green Energy (OSTI)

A catalytic converter thermal management system (TMS) using variable-conductance vacuum insulation and phase-change thermal storage can maintain the converter temperature above its operating temperature for many hours, allowing most trips to begin with minimal ``cold-start`` emissions. The latest converter TMS prototype was tested on a Ford Taurus (3.0 liter flex-fuel engine) at Southwest Research Institute. Following a 24-hour soak, the FTP-75 emissions were 0.031, 0.13, and 0.066 g/mile for NMHC, CO, and NOx, respectively. Tests were also run using 85% ethanol (E85), resulting in values of 0.005, 0.124, and 0.044 g/mile, and 0.005 g/mile NMOG. Compared to the baseline FTP levels, these values represent reductions of 84% to 96% for NMHC, NMOG, and CO.

Burch, S.D.; Keyser, M.A.; Colucci, C.P.; Potter, T.F.; Benson, D.K.; Biel, J.P.

1996-07-01T23:59:59.000Z

246

Liquid metal thermal-electric converter electrode development  

DOE Green Energy (OSTI)

This report describes work done in support of distributed receiver technology development. Dish-electric systems are being pursued in an effort to circumvent the need for energy transport by providing for heat-to-electricity energy conversion by individual heat engines at the focal point of parabolic dish concentrators. The Liquid Metal Thermal-Electric Converter is an engine that can convert thermal energy to electricity without the need for moving parts. The report documents the results of contracted work in the development of a long-lifetime, high-performance electrode for LMTEC, including the materials prepared for it. 17 refs., 20 figs., 3 tabs.

Martinez, J.I. (ed.)

1988-02-01T23:59:59.000Z

247

Process for converting cellulosic materials into fuels and chemicals  

DOE Patents (OSTI)

A process for converting cellulosic materials, such as waste paper, into fuels and chemicals utilizing enzymatic hydrolysis of the major constituent of paper, cellulose. A waste paper slurry is contacted by cellulase in an agitated hydrolyzer. The cellulase is produced from a continuous, columnar, fluidized-bed bioreactor utilizing immobilized microorganisms. An attritor and a cellobiase reactor are coupled to the agitated hydrolyzer to improve reaction efficiency. The cellulase is recycled by an adsorption process. The resulting crude sugars are converted to dilute product in a fluidized-bed bioreactor utilizing microorganisms. The dilute product is concentrated and purified by utilizing distillation and/or a biparticle fluidized-bed bioreactor system.

Scott, Charles D. (Oak Ridge, TN); Faison, Brendlyn D. (Knoxville, TN); Davison, Brian H. (Knoxville, TN); Woodward, Jonathan (Oak Ridge, TN)

1994-01-01T23:59:59.000Z

248

Pre-converted nitric oxide gas in catalytic reduction system  

DOE Patents (OSTI)

A two-stage catalyst comprises an oxidative first stage and a reductive second stage. The first stage is intended to convert NO to NO.sub.2 in the presence of O.sub.2. The second stage serves to convert NO.sub.2 to environmentally benign gases that include N2, CO2, and H.sub.2 O. By preconverting NO to NO.sub.2 in the first stage, the efficiency of the second stage for NO.sub.x reduction is enhanced. For example, an internal combustion engine exhaust is connected by a pipe to a first chamber. An oxidizing first catalyst converts NO to NO.sub.2 in the presence of O.sub.2 and includes platinum/alumina, e.g., Pt/Al.sub.2 O.sub.3 catalyst. A flow of hydrocarbons (C.sub.x H.sub.y) is input from a pipe into a second chamber. For example, propene can be used as a source of hydrocarbons. The NO.sub.2 from the first catalyst mixes with the hydrocarbons in the second chamber. The mixture proceeds to a second reduction catalyst that converts NO.sub.2 to N2, CO2, and H.sub.2 O, and includes a gamma-alumina .gamma.-Al.sub.2 O.sub.3. The hydrocarbons and NO.sub.x are simultaneously reduced while passing through the second catalyst.

Hsiao, Mark C. (Livermore, CA); Merritt, Bernard T. (Livermore, CA); Penetrante, Bernardino M. (San Ramon, CA); Vogtlin, George E. (Fremont, CA)

1999-01-01T23:59:59.000Z

249

Research on MPPT for Solar Cells Based on Flyback Converter  

Science Conference Proceedings (OSTI)

A voltage source and rheostat are successfully used to simulate the solar cell's character in this paper. Its feasibility is analyzed theoretically. The basic principle of the maximum power point tracking (MPPT) is described. An improved disturbance ... Keywords: solar cells, maximum power point tracking (MPPT), flyback converter

Zhang Housheng

2010-05-01T23:59:59.000Z

250

A summary of North American HVDC converter station reliability specifications  

SciTech Connect

This paper summarizes Reliability, Availability, and Maintainability (RAM) specifications that were issued for thyristor based HVDC converter stations in service in North America. A total of twenty project specifications are summarized. A detailed summary by project is shown with specific quantitative requirements categorized. Definitions of terms, representative design principles, and formulas used in calculating RAM parameters contained in existing reliability specifications are presented.

Vancers, I. (ABB Power Systems Inc., Los Angeles, CA (United States)); Hormozi, F.J. (Los Angeles Dept. of Water and Power, CA (United States))

1993-07-01T23:59:59.000Z

251

Energy Savings Assessment for Digital-to-Analog Converter Boxes  

SciTech Connect

The Digital Television (DTV) Converter Box Coupon Program was administered by the U.S. government to subsidize purchases of digital-to-analog converter boxes, with up to two $40 coupons for each eligible household. In order to qualify as Coupon Eligible Converter Boxes (CECBs), these devices had to meet a number of minimum performance specifications, including energy efficiency standards. The Energy Star Program also established voluntary energy efficiency specifications that are more stringent than the CECB requirements. In this study, we measured the power and energy consumptions for a sample of 12 CECBs (including 6 Energy Star labeled models) in-use in homes and estimated aggregate energy savings produced by the energy efficiency policies. Based on the 35 million coupons redeemed through the end of the program, our analysis indicates that between 2500 and 3700 GWh per year are saved as a result of the energy efficiency policies implemented on digital-to-analog converter boxes. The energy savings generated are equivalent to the annual electricity use of 280,000 average US homes.

Cheung, Hoi Ying Iris; Meier, Alan; Brown, Richard

2011-01-18T23:59:59.000Z

252

Apparatus for converting biomass to a pumpable slurry  

DOE Patents (OSTI)

An apparatus used in the pretreatment of wood chips in a process for converting biomass to a liquid hydrocarbonaceous fuel. The apparatus functions to break down the wood chips to a size distribution that can be readily handled in a slurry form. Low maintenance operation is obtained by hydrolyzing the chips in a pressure vessel having no moving parts.

Ergun, Sabri (Hillsborough, CA); Schaleger, Larry L. (Oakland, CA); Wrathall, James A. (Berkeley, CA); Yaghoubzadeh, Nasser (El Cerrito, CA)

1986-01-01T23:59:59.000Z

253

SELECTING FUELS WITHIN ENVIRONMENTAL IMPACT REQUIREMENTS: CONVERTING A  

E-Print Network (OSTI)

SELECTING FUELS WITHIN ENVIRONMENTAL IMPACT REQUIREMENTS: CONVERTING A PRESENT COMBUSTION SYSTEM fossil fuels. Next, the alternative fuels with large po tential energy recovery are selected and presentDIIsrCDUICTOI SCIIU, ! i ItFUS£_pu- ;1II-'NfU1MTJ: 'U.)'// PIr I It \\I I ' I Ir-SUIIDDU\\N. £DI

Columbia University

254

Minimizing power pulsations in a free piston energy converter  

E-Print Network (OSTI)

A Free Piston Energy Converter (FPEC) is a combination of a linear combustion engine and a linear electrical machine. This type of converter has many potential advantages like high efficiency, low fuel consumption and low emissions, which make it suitable for a series hybrid vehicle. However, the generated power pulsates due to the reciprocating motion of the translator. This paper presents a comparative study on how different generator force profiles affect the electric power pulsations produced by the FPEC. In addition, the influence of these profiles on translator motion and the needed power converter current is investigated. A dynamic free piston model is used for the investigation. Results show that the generator force profile has a major impact on the power pulsation amplitude and peak current demand. Thus the chosen force profile will affect dimensioning of power converter, electrical machine and energy storage. Furthermore, loading the translator heavily in the beginning or end of the stroke seems to affect the peak translator velocity more than evenly distributed load profiles.

Jörgen Hansson; Mats Leksell; Fredrik Carlsson

2005-01-01T23:59:59.000Z

255

Elimination of Harmonics in a Multilevel Converter for HEV Applications  

E-Print Network (OSTI)

possible solu- tions are found. Keywords­ Hybrid Electric Vehicles, Multilevel Convert- ers, Harmonic Elimination, Resultants I. Introduction Designs for heavy duty hybrid-electric vehicles (HEVs) that have large electric drives such as tractor trailers, trans- fer trucks, or military vehicles will require advanced

Tolbert, Leon M.

256

Control and Power Management of Converter Fed Microgrids  

E-Print Network (OSTI)

1 Control and Power Management of Converter Fed Microgrids Charles K. Sao, Member, IEEE, and Peter in parallel in a VSC fed microgrid. Each current controlled VSC in such a microgrid has its own VPD/FQB controller that sets its current references to regulate the voltage and frequency of a common microgrid bus

Lehn, Peter W.

257

Converting Site Electricity to Include Generation and Transmission...  

U.S. Energy Information Administration (EIA) Indexed Site

Evaluation of Electricity Consumption in the Manufacturing Division The energy intensities presented in this report do not reflect adjustments for losses in electricity generation...

258

Minimize Boiler Short Cycling Losses  

SciTech Connect

This revised ITP tip sheet on minimizing boiler short cycling losses provides how-to advice for improving industrial steam systems using low-cost, proven practices and technologies.

2006-01-01T23:59:59.000Z

259

Wind turbines convert the kinetic energy in moving air into rotational energy, which in turn is converted  

E-Print Network (OSTI)

Wind turbines convert the kinetic energy in moving air into rotational energy, which in turn the wind doesn't blow? Wind Power on the Community Scale Renewable Energy Research Laboratory, University Energy Research Laboratory brings you this series of fact sheets about Wind Power on the community scale

Massachusetts at Amherst, University of

260

Alternative Fuels Data Center: Yellow Cab Converts Taxis to Propane in  

Alternative Fuels and Advanced Vehicles Data Center (EERE)

Yellow Cab Converts Yellow Cab Converts Taxis to Propane in Columbus, Ohio to someone by E-mail Share Alternative Fuels Data Center: Yellow Cab Converts Taxis to Propane in Columbus, Ohio on Facebook Tweet about Alternative Fuels Data Center: Yellow Cab Converts Taxis to Propane in Columbus, Ohio on Twitter Bookmark Alternative Fuels Data Center: Yellow Cab Converts Taxis to Propane in Columbus, Ohio on Google Bookmark Alternative Fuels Data Center: Yellow Cab Converts Taxis to Propane in Columbus, Ohio on Delicious Rank Alternative Fuels Data Center: Yellow Cab Converts Taxis to Propane in Columbus, Ohio on Digg Find More places to share Alternative Fuels Data Center: Yellow Cab Converts Taxis to Propane in Columbus, Ohio on AddThis.com... July 9, 2011 Yellow Cab Converts Taxis to Propane in Columbus, Ohio

Note: This page contains sample records for the topic "loss torque converter" 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

NETL: News Release - Secretary Chu Announces Six Projects to Convert  

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

2, 2010 2, 2010 Secretary Chu Announces Six Projects to Convert Captured CO2 Emissions from Industrial Sources into Useful Products $106 Million Recovery Act Investment Will Reduce CO2 Emissions and Mitigate Climate Change Washington, D.C. - U.S. Energy Secretary Steven Chu announced today the selections of six projects that aim to find ways of converting captured carbon dioxide (CO2) emissions from industrial sources into useful products such as fuel, plastics, cement, and fertilizers. Funded with $106 million from the American Recovery and Reinvestment Act -matched with $156 million in private cost-share -today's selections demonstrate the potential opportunity to use CO2 as an inexpensive raw material that can help reduce carbon dioxide emissions while producing useful by-products that Americans can use.

262

NREL: News - NREL to Help Convert Methane to Liquid Diesel  

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

113 113 NREL to Help Convert Methane to Liquid Diesel Advanced research project could lead to lower greenhouse emissions, new life for spent gas and oil wells January 3, 2013 The U.S. Department of Energy's (DOE) National Renewable Energy Laboratory (NREL) will help develop microbes that convert methane found in natural gas into liquid diesel fuel, a novel approach that if successful could reduce greenhouse gas emissions and lower dependence on foreign oil. The amount of natural gas simply flared or vented from oil wells globally is enormous - equal to one-third of the amount of petroleum used in the United States each year. And every molecule of methane vented to the atmosphere in that process has the global-warming capacity of 12 molecules of carbon dioxide.

263

GTRI's Convert Program: Minimizing the Use of Highly Enriched Uranium |  

National Nuclear Security Administration (NNSA)

Program: Minimizing the Use of Highly Enriched Uranium | Program: Minimizing the Use of Highly Enriched Uranium | National Nuclear Security Administration Our Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response Recapitalizing Our Infrastructure Continuing Management Reform Countering Nuclear Terrorism About Us Our Programs Our History Who We Are Our Leadership Our Locations Budget Our Operations Media Room Congressional Testimony Fact Sheets Newsletters Press Releases Speeches Events Social Media Video Gallery Photo Gallery NNSA Archive Federal Employment Apply for Our Jobs Our Jobs Working at NNSA Blog Home > Media Room > Fact Sheets > GTRI's Convert Program: Minimizing the Use of ... Fact Sheet GTRI's Convert Program: Minimizing the Use of Highly Enriched Uranium Apr 12, 2013

264

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

265

Combined Effects of Gravity, Bending Moment, Bearing Clearance, and Input Torque on Wind Turbine Planetary Gear Load Sharing: Preprint  

DOE Green Energy (OSTI)

This computational work investigates planetary gear load sharing of three-mount suspension wind turbine gearboxes. A three dimensional multibody dynamic model is established, including gravity, bending moments, fluctuating mesh stiffness, nonlinear tooth contact, and bearing clearance. A flexible main shaft, planetary carrier, housing, and gear shafts are modeled using reduced degrees-of-freedom through modal compensation. This drivetrain model is validated against the experimental data of Gearbox Reliability Collaborative for gearbox internal loads. Planet load sharing is a combined effect of gravity, bending moment, bearing clearance, and input torque. Influences of each of these parameters and their combined effects on the resulting planet load sharing are investigated. Bending moments and gravity induce fundamental excitations in the rotating carrier frame, which can increase gearbox internal loads and disturb load sharing. Clearance in carrier bearings reduces the bearing load carrying capacity and thus the bending moment from the rotor can be transmitted into gear meshes. With bearing clearance, the bending moment can cause tooth micropitting and can induce planet bearing fatigue, leading to reduced gearbox life. Planet bearings are susceptible to skidding at low input torque.

Guo, Y.; Keller, J.; LaCava, W.

2012-09-01T23:59:59.000Z

266

Digital signal processing control of induction machine`s torque and stator flux utilizing the direct stator flux field orientation method  

SciTech Connect

This paper presents a review of the Direct Stator Flux Field Orientation control method. This method can be used to control an induction motor`s torque and flux directly and is the application of interest for this thesis. This control method is implemented without the traditional feedback loops and associated hardware. Predictions are made, by mathematical calculations, of the stator voltage vector. The voltage vector is determined twice a switching period. The switching period is fixed throughout the analysis. The three phase inverter duty cycle necessary to control the torque and flux of the induction machine is determined by the voltage space vector Pulse Width Modulation (PWM) technique. Transient performance of either the flux or torque requires an alternate modulation scheme which is also addressed in this thesis. A block diagram of this closed loop system is provided. 22 figs., 7 tabs.

Seiz, J.B.

1997-04-01T23:59:59.000Z

267

Catalyst for converting synthesis gas to liquid motor fuels  

DOE Patents (OSTI)

The addition of an inert metal component, such as gold, silver or copper, to a Fischer-Tropsch catalyst comprising cobalt enables said catalyst to convert synthesis gas to liquid motor fuels at about 240.degree.-370.degree. C. with advantageously reduced selectivity of said cobalt for methane in said conversion. The catalyst composition can advantageously include a support component, such as a molecular sieve, co-catalyst/support component or a combination of such support components.

Coughlin, Peter K. (Yorktown Heights, NY)

1986-01-01T23:59:59.000Z

268

MHK Technologies/OCEANTEC Wave Energy Converter | Open Energy Information  

Open Energy Info (EERE)

Wave Energy Converter Wave Energy Converter < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage OCEANTEC Wave Energy Converter.jpg Technology Profile Primary Organization OCEANTEC Energias Marinas S L Technology Resource Click here Wave Technology Type Click here Attenuator Technology Readiness Level Click here TRL 5 6 System Integration and Technology Laboratory Demonstration Technology Description OCEANTEC Marine Energy Company Ltd owned by Iberdrola and TECNALIA is developing a sensor for wave energy technology type Spanish attenuator Floating body oscillates due to wave excitation in its main DOF pitch Mooring system allows the body to weathervane so that it is faced to the predominant wave propagation direction Main advantage capture system completely encapsulated free of contact with sea water A flywheel continuously spins under the action of an electric motor Z The pitching motion of the WEC caused by wave action is transformed into an alternating precession in the longitudinal hull axis X A coupling device transforms this precession into an unidirectional rotation of higher frequency that is used to feed a conventional electric generator

269

Analog-to-digital converter with data processing  

DOE Patents (OSTI)

This device incorporates an analog-digital converter including a data processing section which can be used to perform data processing on digitized data as is generated, off-line from the system processor. It consists of a 12 bit analog to digital converter for generating discrete digital data representative of an input analog signal, a data bus coupled to receive the digital data as is generated, a 512 Kbyte memory RAM to store the digitized data, and a system bus coupled to the data processing element for outputting the result of the performed operation. This is the first device with analog to digital converters and memory. It is the first module to be designed to the VXIbus format. This device is the first to incorporate an averaging circuit in the design. It has a sealed analog module (outputs the sum and difference of the log signals for both the X and the Y axis of the beam position module), memory channels, four averaging channels the programmable trigger and digitizer clock logic, and a VXIbus interface. This device is useful in the fields of data acquisition, data processing, communication systems, instrumentation and electronics.

Jones, A.

1993-01-01T23:59:59.000Z

270

Trimode Power Converter optimizes PV, diesel and battery energy sources  

SciTech Connect

Conservatively, there are 100,000 localities in the world waiting for the benefits that electricity can provide, and many of these are in climates where sunshine is plentiful. With these locations in mind a prototype 30 kW hybrid system has been assembled at Sandia to prove the reliability and economics of photovoltaic, diesel and battery energy sources managed by an autonomous power converter. In the Trimode Power Converter the same power parts, four IGBT`s with an isolation transformer and filter components, serve as rectifier and charger to charge the battery from the diesel; as a stand-alone inverter to convert PV and battery energy to AC; and, as a parallel inverter with the diesel-generator to accommodate loads larger than the rating of the diesel. Whenever the diesel is supplying the load, an algorithm assures that the diesel is running at maximum efficiency by regulating the battery charger operating point. Given the profile of anticipated solar energy, the cost of transporting diesel fuel to a remote location and a five year projection of load demand, a method to size the PV array, battery and diesel for least cost is developed.

O`Sullivan, G. [Abacus Controls, Inc., Somerville, NJ (United States); Bonn, R.; Bower, W. [Sandia National Labs., Albuquerque, NM (United States)

1994-07-01T23:59:59.000Z

271

OPERATIONAL RESULTS OF THE SPALLATION NEUTRON SOURCE (SNS) POLYPHASE CONVERTER-MODULATOR FOR THE 140 KV KLYSTRON RF SYSTEMS  

SciTech Connect

This paper describes the first operational results of the 140 kV, 1 MW average, 11 MW peak, zero-voltage-switching, 20 kHz polyphase bridge, boost converter-modulator for klystron pulse application. The DC-DC converter derives the buss voltages from a standard 13.8 kV to 2100 Y substation cast-core transformer. Energy storage and filtering is provided by self-clearing metallized hazy polypropylene traction capacitors. Three ''H-Bridge'' Insulated Gate Bipolar Transistor (IGBT) switching networks are used to generate the polyphase 20 kHz transformer primary drive waveforms. The 20 kHz drive waveforms are chirped the appropriate duration to generate the desired klystron pulse width. Pulse-Width Modulation (PWM) of the individual 20 kHz pulses is utilized to provide regulated output waveforms with adaptive feedforward and feedback techniques. The boost transformer design utilizes amorphous nanocrystalline material that provides the required low core loss at design flux levels and switching frequencies. Resonant shunt peaking is used on the transformer secondary to boost output voltage and resonate transformer leakage inductance. With the appropriate transformer leakage inductance and peaking capacitance, zero-voltage-switching of the IGBT's is attained, minimizing switching losses. Reviews of these design parameters and an examination of the first operational results will be performed.

W.A. REASS; J.D. DOSS; ET AL

2001-06-01T23:59:59.000Z

272

Operational results of the spallation neutron source (SNS) polyphase converter-modulator for the 140 KV klystron RF system  

SciTech Connect

This paper describes the first operational results of the 140 kV, 1 MW average, 11 MW peak, zero-voltageswitching, 20 kHz polyphase bridge, boost converter-modulator for klystron pulse application. The DC-DC converter derives the buss voltages from a standard 13.8 kV to 2100 Y substation cast-core transformer. Energy storage and filtering is provided by self-clearing metallized hazy polypropylene traction capacitors. Three 'H-Bridge' Insulated Gate Bipolar Transistor (IGBT) switching networks are used to generate the polyphase 20 kHz transformer primary drive waveforms. The 20 kHz drive waveforms are chirped the appropriate duration to generate the desired klystron pulse width. Pulse-Width Modulation (PWM) of the individual 20 kHz pulses is utilized to provide regulated output waveforms with adaptive feedforward and feedback techniques. The boost transformer design utilizes amorphous nanocrystalline material that provides the required low core loss at design flux levels and switching frequencies. Resonant shunt peaking is used on the transformer secondary to boost output voltage and resonate transformer leakage inductance. With the appropriate transformer leakage inductance and peaking capacitance, zero-voltage-switching of the IGBT's is attained, minimizing switching losses. Reviews of these design parameters and an examination of the first operational results will be performed.

Reass, W. A. (William A.); Doss, James D.; Gribble, R. F. (Robert F.); Lynch, M. T. (Michael T.); Rees, D. E. (Daniel E.); Tallerico, P. J. (Paul J.); Borovina, D. L.

2001-01-01T23:59:59.000Z

273

Operational results of the spallation neutron source (SNS) polyphase converter-modulator for the 140 KV klystron RF system  

DOE Green Energy (OSTI)

This paper describes the first operational results of the 140 kV, 1 MW average, 11 MW peak, zero-voltageswitching, 20 kHz polyphase bridge, boost converter-modulator for klystron pulse application. The DC-DC converter derives the buss voltages from a standard 13.8 kV to 2100 Y substation cast-core transformer. Energy storage and filtering is provided by self-clearing metallized hazy polypropylene traction capacitors. Three 'H-Bridge' Insulated Gate Bipolar Transistor (IGBT) switching networks are used to generate the polyphase 20 kHz transformer primary drive waveforms. The 20 kHz drive waveforms are chirped the appropriate duration to generate the desired klystron pulse width. Pulse-Width Modulation (PWM) of the individual 20 kHz pulses is utilized to provide regulated output waveforms with adaptive feedforward and feedback techniques. The boost transformer design utilizes amorphous nanocrystalline material that provides the required low core loss at design flux levels and switching frequencies. Resonant shunt peaking is used on the transformer secondary to boost output voltage and resonate transformer leakage inductance. With the appropriate transformer leakage inductance and peaking capacitance, zero-voltage-switching of the IGBT's is attained, minimizing switching losses. Reviews of these design parameters and an examination of the first operational results will be performed.

Reass, W. A. (William A.); Doss, James D.; Gribble, R. F. (Robert F.); Lynch, M. T. (Michael T.); Rees, D. E. (Daniel E.); Tallerico, P. J. (Paul J.); Borovina, D. L.

2001-01-01T23:59:59.000Z

274

OPERATIONAL RESULTS OF THE SPALLATION NEUTRON SOURCE (SNS) POLYPHASE CONVERTER-MODULATOR FOR THE 140 KV KLYSTRON RF SYSTEMS  

SciTech Connect

This paper describes the first operational results of the 140 kV, 1 MW average, 11 MW peak, zero-voltage-switching, 20 kHz polyphase bridge, boost converter-modulator for klystron pulse application. The DC-DC converter derives the buss voltages from a standard 13.8 kV to 2100 Y substation cast-core transformer. Energy storage and filtering is provided by self-clearing metallized hazy polypropylene traction capacitors. Three ''H-Bridge'' Insulated Gate Bipolar Transistor (IGBT) switching networks are used to generate the polyphase 20 kHz transformer primary drive waveforms. The 20 kHz drive waveforms are chirped the appropriate duration to generate the desired klystron pulse width. Pulse-Width Modulation (PWM) of the individual 20 kHz pulses is utilized to provide regulated output waveforms with adaptive feedforward and feedback techniques. The boost transformer design utilizes amorphous nanocrystalline material that provides the required low core loss at design flux levels and switching frequencies. Resonant shunt peaking is used on the transformer secondary to boost output voltage and resonate transformer leakage inductance. With the appropriate transformer leakage inductance and peaking capacitance, zero-voltage-switching of the IGBT's is attained, minimizing switching losses. Reviews of these design parameters and an examination of the first operational results will be performed.

W.A. REASS; J.D. DOSS; ET AL

2001-06-01T23:59:59.000Z

275

The Effects of Stator Compliance, Backs Steps, Temperature, and Clockwise Rotation on the Torque-Speed Curve of Bacterial Flagellar Motor  

E-Print Network (OSTI)

Rotation of a single bacterial flagellar motor is powered by multiple stators tethered to the cell wall. In a "power-stroke" model the observed independence of the speed at low load on the number of stators is explained by a torque-dependent stepping mechanism independent of the strength of the stator tethering spring. On the other hand, in models that depend solely on the stator spring to explain the observed behavior, exceedingly small stator spring constants are required. To study the dynamics of the motor driven by external forces (such as those exerted by an optical tweezer), back-stepping is introduced when stators are driven far out of equilibrium. Our model with back-stepping reproduces the observed absence of a barrier to backward rotation, as well the behaviors in the high-speed negative-torque regime. Recently measured temperature dependence of the motor speed near zero load (Yuan & Berg 2010 Biophys J) is explained quantitatively by the thermally activated stepping rates in our model. Finally, we suggest that the general mechanical properties of all molecular motors (linear and rotary), characterized by their force(torque)-speed curve, can be determined by their power-stroke potentials and the dependence of the stepping rates on the mechanical state of the motor (force or speed). The torque-speed curve for the clockwise rotating flagellar motor has been observed for the first time recently (Yuan et al. 2010 PNAS). Its quasi-linear behavior is quantitatively reproduced by our model. In particular, we show that concave and convex shapes of the torque-speed curve can be achieved by changing the interaction potential from linear to quadratic form. We also show that reversing the stepping rate dependence on force (torque) can lead to non-monotonicity in the speed-load dependency.

Giovanni Meacci; Ganhui Lan; Yuhai Tu

2010-08-13T23:59:59.000Z

276

Energy Loss by Breaking waves  

Science Conference Proceedings (OSTI)

Observations of the frequency of wind wave breaking in deep water are combined with laboratory estimates of the rate of energy loss a from single breaking wave to infer the net rate of energy transfer to the mixed layer from breaking waves, as a ...

S. A. Thorpe

1993-11-01T23:59:59.000Z

277

Directed reflectivity, long life AMTEC condenser (DRC). Final report of Phase II SBIR program[Alkali Metal ThermoElectric Converter  

DOE Green Energy (OSTI)

The Alkali Metal Thermal to Electric Converter (AMTEC) is a static energy conversion device that operates at high thermal to electric conversion efficiencies that are essentially independent of size, have reached 19% and are expected to reach 25% to 30% in 1997. AMTEC systems have been chosen by NASA and DOE for spacecraft applications and have considerable promise for a wide variety of terrestrial applications. Reduction of parasitic heat losses in AMTEC systems related to radiative heat transfer from the hot side to the condenser can make a substantial contribution to system efficiency. Through design, analysis and the fabrication and testing of cells and systems, the proposed program to develop a Directed Reflectivity Condenser (DRC) has investigated the feasibility of an improved AMTEC condenser component. Phase 1 work showed the potential for adding from 4% to 7% to overall system efficiency for identical operating conditions using the concept. A detailed thermal analysis of several DRC capped cell designs was carried out and some of the conditions under which a DRC, used as the condenser at an end cap of a cylindrical converter, can reduce thermal radiation related losses were determined. A model experimental converter was built and tested to compare DRC and planar condenser surfaces. The results of both analysis and experiment indicate that for moderate aspect ratios of a cylindrical, end condensed converter, the DRC can reduce overall thermal losses by up to 4%. The initial effort in Phase 2 extended the analysis to a novel 150 watt radial AMTEC cell design. This analysis indicated that for the effective aspect ratio of this new converter design, the system performance at the 100+ watt level was not significantly improved by use of a DRC type condenser surface. Further analyses however showed that for cylindrical, end-condensed converters, optimized for use with internal radiation shields, the use of DRC surfaces on the side walls of the converter could be more effective than on the condenser end surface itself. The experimental work in Phase 2 was intended to incorporate a DRC into this cell design and use its measured performance to refine the state-of-the-art AMTEC analytical models. Because the analysis had indicated that the new radial converter design, which may be useful for systems at the {approx} 100 watt level was not much assisted by the DRC properties, this program was redirected toward the simpler cylindrical converter design with the corner cube surfaces on the side walls. The Phase II program was proposed and planned with a funding level substantially below the maximum potentially available for Phase II programs at that time. At the time, there were two other funded government sponsored programs at AMPS for which positive results of the analyses described in this report were expected to lead to incorporation of the DRC concept into converters scheduled to be built for these programs. The programs of interest were the Air Force program titled ''Radiation Tolerant, Eclipse Compatible, Solar AMTEC System'' (F29601-99-C-0132) and the DOE/NASA Advanced Radioisotope Power System (ARPS) program. Shortly after its start, the Air Force program was canceled due to elimination of AF SBIR funds at AFRL and the ARPS program was reduced to a level that could not support introduction of novel concept testing. As a result of these two circumstances, the direct testing of the DRC concept in a full up converter was not completed in the Phase II period.

Hunt, Thomas K.

2001-09-10T23:59:59.000Z

278

Two U.S. University Research Reactors to be Converted From Highly...  

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

are here Home Two U.S. University Research Reactors to be Converted From Highly Enriched Uranium to Low-Enriched Uranium Two U.S. University Research Reactors to be Converted...

279

Blind calibration of timing skew in time-interleaved analog-to-digital converters  

E-Print Network (OSTI)

The performance of time-interleaved analog-to-digital converters is often significantly degraded by timing mismatch errors. We develop methods for performing blind calibration of such converters, i.e., for estimating the ...

Divi, Vijay

280

Design and characterization of a radio-frequency dc/dc power converter  

E-Print Network (OSTI)

The use of radio-frequency (RF) amplifier topologies in dc/dc power converters allows the operating frequency to be increased by more than two orders of magnitude over the frequency of conventional converters. This enables ...

Jackson, David A. (David Alexander)

2005-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "loss torque converter" 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

A Decentralized Protection Scheme for Converters Utilizing a DC-link Inductor  

E-Print Network (OSTI)

, and B. Ooi. Force commutated HVDC and SVC based on phase-shifted multi-converter modules. IEEE Trans

Lipo, Thomas

282

Custom DC-DC converters for distributing power in SLHC trackers  

E-Print Network (OSTI)

A power distribution scheme based on the use of on-board DC-DC converters is proposed to efficiently distribute power to the on-detector electronics of SLHC trackers. A comparative analysis of different promising converter topologies is presented, leading to the choice of a magneticbased buck converter as a first conversion stage followed by an on-chip switched capacitors converter. An overall efficiency above 80% is estimated for the practical implementation proposed.

Allongue, B; Blanchot, G; Faccio, F; Fuentes, C; Mattavelli, P; Michelis, S; Orlandis, S; Spiazzi, G

2008-01-01T23:59:59.000Z

283

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

284

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

285

Harmonic measurements from a group connected generator HVdc converter scheme  

SciTech Connect

A recent CIGRE document published in ELECTRA has described the potential benefits of a direct connection of generators to HVdc converters. While many theoretical contributions have been made, no practical test data has become available so far. This paper reports on harmonic tests carried out at the Benmore end of the New Zealand HVdc link operating as a group connected scheme. It was found that the measured harmonic current levels were well below specified generator ratings. Dynamic simulation accurately predicted the harmonic currents whereas the results of a steady state formulation were less reliable.

Macdonald, S.J.; Enright, W.; Arrillaga, J. [Univ. of Canterbury, Christchurch (New Zealand); O`Brien, M.T.

1995-10-01T23:59:59.000Z

286

Bi-Directional DC-DC Converter for PHEV Applications  

DOE Green Energy (OSTI)

Plug-In Hybrid Electric Vehicles (PHEV) require high power density energy storage system (ESS) for hybrid operation and high energy density ESS for Electric Vehicle (EV) mode range. However, ESS technologies to maximize power density and energy density simultaneously are not commercially feasible. The use of bi-directional DC-DC converter allows use of multiple energy storage, and the flexible DC-link voltages can enhance the system efficiency and reduce component sizing. This will improve fuel consumption, increase the EV mode range, reduce the total weight, reduce battery initial and life cycle cost, and provide flexibility in system design.

Abas Goodarzi

2011-01-31T23:59:59.000Z

287

Fast-scale bifurcation . . . converters and effects of incompatible periodicities  

E-Print Network (OSTI)

In this paper, we derive the discrete-time model for the power-factor-correction (PFC) buck-boost converter in terms of a stroboscopic switching map. Fast-scale instability is analysed through a fold diagram, which exposes the periodicity of the operation as well as the locations of the critical phase angles of the line voltage at which instability begins to occur along a half-line cycle. The asymmetrical locations of the critical phase angles along a half-line cycle is explained in terms of ‘underdeveloped’ bifurcation. Border collision bifurcations are observed and analysed in detail.

Jianlong Zou; Xikui Ma; Chi K. Tse; Dong Dai

2006-01-01T23:59:59.000Z

288

dc-to-ac power converter for fuel cell system  

SciTech Connect

As the interface between fuel cells and the utility line, a self-commutated inverter is preferred to a line-commutated inverter because of its easy controllability. Using the gate turn off (GTO) thyristors, this inverter can have high efficiency and simple circuit configurations. This paper describes the design features and test results of the dc-to-ac power converter, which is principally composed of four-phase transistor chopper and 12-pulse GTO inverter, for a 50kW experimental fuel cell power system. Furthermore, new GTO inverter which improves the circuit efficiency is presented. Special emphasis is placed on a detailed analysis and evaluation of this GTO inverter.

Kawabata, T.; Asaeda, T.; Hamasaki, Y.; Yutani, T.

1983-10-01T23:59:59.000Z

289

A new arrangement of AC/DC converters for high direct-current applications  

Science Conference Proceedings (OSTI)

A novel AC/DC converter designed for high-output direct currents and tight output voltage regulations is introduced. The proposed converter exhibits good efficiency and very low output voltage ripple. In order to verify the performances of the four-stage ... Keywords: AC/DC converter, FFT, electrical distribution systems, high direct-current

Francesco Muzi; Luigi Passacantando

2008-04-01T23:59:59.000Z

290

Multi-Stage Converters: A New Technology for Traction Drive Juan W. Dixon  

E-Print Network (OSTI)

of this drive is that the switching frequency of the Main converter is at the fundamental frequency, reducing will be the Slaves. The Main Converter works at the lower switching frequency (fundamental frequency), which, and A. Tahri, "Multilevel Converters and VAR Compensation", Chapter 25, Power Electronics Handbook

Rudnick, Hugh

291

Microgrid Power Electronic Converters: State of the Art and Future Challenges  

E-Print Network (OSTI)

Microgrid Power Electronic Converters: State of the Art and Future Challenges M. Jamil, B. Hussain converters used in microgrids. The paper focuses primarily on grid connected converters. Different topologies as they are variable in nature. Distributed generators (DG), including renewable sources, within microgrids can help

292

Efficient, High-Torque Electric Vehicle Motor: Advanced Electric Vehicle Motors with Low or No Rare Earth Content  

SciTech Connect

REACT Project: QM Power will develop a new type of electric motor with the potential to efficiently power future generations of EVs without the use of rare-earth-based magnets. Many of today’s EV motors use rare earth magnets to efficiently provide torque to the wheels. QM Power’s motors would contain magnets that use no rare earth minerals, are light and compact, and can deliver more power with greater efficiency and at reduced cost. Key innovations in this project include a new motor design with iron-based magnetic materials, a new motor control technique, and advanced manufacturing techniques that substantially reduce the cost of the motor. The ultimate goal of this project is to create a cost-effective EV motor that offers the rough peak equivalent of 270 horsepower.

None

2012-01-01T23:59:59.000Z

293

Sound energy loss during sonolysis  

Science Conference Proceedings (OSTI)

This paper gives an analysis of sound energy losses due to sonolysis — dissociation of the part of water molecules to radicals H? and ?OH. The value of the energy loss can be evaluated by using the concentration of hydrogen peroxide which appears in the water as a result of cross?recombination of radicals ?OH+?OH=H2O2. Data previously obtained by different authors were used for the present analysis. Data for fresh water and also for water with dissolved gases were considered. Data covered a sound frequency range from 1.5 kHz to 2 MHz and sound pressure amplitudes 0.6–2.5 atm for normal static pressure and a water temperature of 20?°C. It is shown that the rate of increasing hydrogen peroxide concentration is proportional to the intensity of sound. The rate is also propor? tional to the concentration of dissolved oxygen and argon in water while other gases (hydrogen

Dmitry A. Selivanovsky; Grigory A. Domrachev

1995-01-01T23:59:59.000Z

294

This work presents an improved variant of the Direct Torque Control (DTC) for a Permanent Magnet Synchronous Motor (PMSM). The improved DTC use a higher  

E-Print Network (OSTI)

Magnet Synchronous Motor (PMSM). The improved DTC use a higher number of voltage space vectors;Contents I Introduction 5 Chapter 1 Permanent Magnet Synchronous Motor 6 1.1 Derivation of motor equations Voltage Source Inverter PMSM Permanent Magnet Synchronous Motor 4 #12;I. Introduction Direct Torque

Johansson, Karl Henrik

295

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

296

EMISSIONS REDUCTIONS USING HYDROGEN FROM PLASMATRON FUEL CONVERTERS  

DOE Green Energy (OSTI)

Substantial progress in engine emission control is needed in order to meet present and proposed regulations for both spark ignition and diesel engines. Tightening regulations throughout the world reflect the ongoing concern with vehicle emissions. Recently developed compact plasmatron fuel converters have features that are suitable for onboard production of hydrogen for both fuel pretreatment and for exhaust aftertreatment applications. Systems that make use of these devices in conjunction with aftertreatment catalysts have the potential to improve significantly prospects for reduction of diesel engine emissions. Plasmatron fuel converters can provide a rapid response compact means to transform efficiently a wide range of hydrocarbon fuels into hydrogen rich gas. They have been used to reform natural gas [Bromberg1], gasoline [Green], diesel [Bromberg2] and hard-to-reform biofuels [Cohn1] into hydrogen rich gas (H2 + CO). The development of these devices has been pursued for the purpose of reducing engine exhaust pollutants by providing hydrogen rich gas for combustion in spark ignition and possibly diesel engines, as shown in Figure 1 [Cohn2]. Recent developments in compact plasmatron reformer design at MIT have resulted in substantial decreases in electrical power requirements. These new developments also increase the lifetime of the electrodes.

Bromberg, L

2000-08-20T23:59:59.000Z

297

Characterization of B2H6 Plasma Doping for Converted p+ Poly-Si Gate  

SciTech Connect

We have investigated the characteristics of B2H6 plasma doping (PLAD) process used to convert the n+ doped poly-Si gate to the p+ poly-Si gate for pMOS. The throughput of the PLAD process is much higher than a conventional beam line implantation process at low energy and high dose ranges. The B2H6 plasma counter-doping on the n+ poly-Si were performed in the energy range of 5kV {approx} 9kV and dose of {approx}E16 number sign /cm2. The B2H6 Plasma doped poly-Si layers were characterized by TDS, SIMS, AFM, and TEM.The TDS analysis showed hydrogen desorption from the B2H6 plasma doped p+ poly-Si layer at a low temperature. The surface concentration of PLAD doped boron was much higher compared to the conventional beam line implantation. However, a serious loss of surface dopant was also observed during photoresist strip and post cleaning. The surface dopant loss could be suppressed by 10% with optimization of the cleaning condition, leading to improve characteristics of PLAD doped p+ poly-Si pMOS, compared to the beam line implantation. Moreover, flat band voltage (VFB) shift was not observed in the C-V curves and there was no significant difference in I-V characteristics between PLAD and the conventional ion implantation. Deeper and higher dopant profile will be helpful to decrease required dose gap between PLAD and beam line implantation.

Oh, Jae-Geun; Lee, J. K.; Hwang, S. H.; Cho, H. J.; Sohn, Y. S.; Sheen, D. S.; Pyi, S. H. [Hynix Semiconductor Inc., San 136-1 Ami-ri, Bubal-eub, Ichon-si, Kyoungki-do, 467-701 (Korea, Republic of); Lee, S. W.; Hahn, S. H. [Varian Korea Ltd., 433-1 Mogok-dong Pyeongtaek-si Kyoungki-do 459-040 (Korea, Republic of); Jeon, Y. B.; Fang, Z.; Singh, V. [Varian Semiconductor Equipment Associates Incorporate, 35 Dory Road, Gloucester, MA 01930 (United States)

2006-11-13T23:59:59.000Z

298

New generation polyphase resonant converter-modulators for the Korean atomic energy research institute  

SciTech Connect

This paper will present operational data and performance parameters of the newest generation polyphase resonant high voltage converter modulator (HVCM) as developed and delivered to the KAERI 100 MeV ''PEFP'' accelerator [1]. The KAERI design realizes improvements from the SNS and SLAC designs [2]. To improve the IGBT switching performance at 20 kHz for the KAERI system, the HVCM utilizes the typical zero-voltage-switching (ZVS) at turn on and as well as artificial zero-current-switching (ZCS) at turn-off. The new technique of artificial ZCS technique should result in a 6 fold reduction of IGBT switching losses (3). This improves the HCVM conversion efficiency to better than 95% at full average power, which is 500 kW for the KAERI two klystron 105 kV, 50 A application. The artificial ZCS is accomplished by placing a resonant RLC circuit across the input busswork to the resonant boost transformer. This secondary resonant circuit provides a damped ''kick-back'' to assist in IGBT commutation. As the transformer input busswork is extremely low inductance (< 10 nH), the single RLC network acts like it is across each of the four IGBT collector-emitter terminals of the H-bridge switching network. We will review these topological improvements and the overall system as delivered to the KAERI accelerator and provide details of the operational results.

Reass, William A [Los Alamos National Laboratory; Baca, David M [Los Alamos National Laboratory; Gribble, Robert F [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

299

Thermally induced evolution of morphology on ceramic surfaces in a thermionic converter  

DOE Green Energy (OSTI)

The morphology of alumina and scandia ceramics exposed to controlled vacuum and diffusion modes in a thermionic converter has been studied. Evidence for vaporization at a temperature of 1,770 K is manifest in the resulting surface morphologies of both ceramics, consistent with reported sample mass loss. Alumina shows intergranular relief with the formation of terrace--step structure on the grain surfaces. Terrace formation is not directly observed on scandia, however the development of vertical structure and maintenance of voids indicates that vaporization is initiated by structure at the grain edges. Extensive Sc{sub 2}O{sub 3} re-deposition occurs on the scandia surface, possibly mediated by the presence of molybdenum and tungsten. Evidence exists for refractory metal secondary phase formation in this deposit in the form of Sc{sub 6}MO{sub 12} (M = W or Mo). Alumina also shows evidence for materials` interactions in the form of tantalum assisted vaporization which significantly alters the terrace structure.

Zavadil, K.R. [Sandia National Labs., Albuquerque, NM (United States); Olson, D.L. [Team Specialty Services, Albuquerque, NM (United States); Klinkov, A.E. [JS Intertek, Kurchatov (Russian Federation)

1996-12-01T23:59:59.000Z

300

Development of a Novel Bi-Directional Isolated Multiple-Input DC-DC Converter  

DOE Green Energy (OSTI)

There is vital need for a compact, lightweight, and efficient energy-storage system that is both affordable and has an acceptable cycle life for the large-scale production of electric vehicles (EVs) and hybrid electric vehicles (HEVs). Most of the current research employs a battery-storage unit (BU) combined with a fuel cell (FC) stack in order to achieve the operating voltage-current point of maximum efficiency for the FC system. A system block diagram is shown in Fig.1.1. In such a conventional arrangement, the battery is sized to deliver the difference between the energy required by the traction drive and the energy supplied by the FC system. Energy requirements can increase depending on the drive cycle over which the vehicle is expected to operate. Peak-power transients result in an increase of losses and elevated temperatures which result in a decrease in the lifetime of the battery. This research will propose a novel two-input direct current (dc) dc to dc converter to interface an additional energy-storage element, an ultracapacitor (UC), which is shown in Fig.1.2. It will assist the battery during transients to reduce the peak-power requirements of the battery.

Li, H.

2005-10-24T23:59:59.000Z

Note: This page contains sample records for the topic "loss torque converter" 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

Mechanical model for ductility loss  

Science Conference Proceedings (OSTI)

A mechanical model was constructed to probe into the mechanism of ductility loss. Fracture criterion based on critical localized deformation was undertaken. Two microstructure variables were considered in the model. Namely, the strength ratio of grain boundary affected area to the matrix, ..cap omega.., and the linear fraction, x, of grain boundary affected area. A parametrical study was carried out. The study shows that the ductility is very sensitive to those microstructure parameters. The functional dependence of ductility to temperature as well as strain-rate, suggested by the model, is demonstrated to be consistent with the observation.

Hu, W.L.

1980-02-11T23:59:59.000Z

302

NETL: News Release - Converting Coal Wastes to Clean Energy  

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

November 28, 2000 November 28, 2000 Converting Coal Wastes to Clean Energy DOE to Scale Up 3 Projects That Upgrade Coal Fines, Wastes PITTSBURGH, PA - Three new technologies that can help the nation's coal industry turn waste into energy are now ready for scale up, the U.S. Department of Energy said today. MORE INFO Solid Fuels & Feedstocks Program Each of the three recover carbon-rich materials that in the past have been discarded during coal mining and cleaning operations. Using innovative approaches, the technologies remove unwanted water and other impurities and upgrade the waste materials into clean-burning fuels for power plants. The three were first selected for smaller-scale research in August 1998 as part of the Energy Department's Fossil Energy "solid fuels and feedstocks"

303

Neutronic design studies for the MIT fission converter beam  

SciTech Connect

Currently available epithermal neutron beams at the Massachusetts Institute of Technology (MIT) are not sufficiently intense to meet the anticipated demand for boron neutron capture therapy (BNCT) treatments if initial, currently in progress clinical trials of BNCT prove successful. Indeed, they are not really adequate for extensive (phase-III) clinical trials. To fulfill this need, a high-intensity, high-quality fission converter-based epithermal neutron beam for BNCT has been designed for the MIT Research Reactor, (MITR-II). This epithermal neutron beam, capable of delivering treatments in a few minutes with negligible beam background contamination, would be installed in the present thermal column and hohlraum of the MITR-II.

Kiger, W.S. III; Harling, O.K. [Massachusetts Inst. of Technology, Cambridge, MA (United States)

1996-12-31T23:59:59.000Z

304

A Study of Radiative Bottomonium Transitions using Converted Photons  

SciTech Connect

The authors use (111 {+-} 1) million {Upsilon}(3S) and (89 {+-} 1) million {Upsilon}(2S) events recorded by the BABAR detector at the PEP-II B-factory at SLAC to perform a study of radiative transitions betwen bottomonium states using photons that have been converted to e{sup +}e{sup -} pairs by the detector material. They observe {Upsilon}(3S) {yields} {gamma}{chi}{sub b0,2}(1P) decay, make precise measurements of the branching fractions for {chi}{sub b1,2}(1P, 2P) {yields} {gamma}{Upsilon}(1S) and {chi}{sub b1,2}(2P) {yields} {gamma}{Upsilon}(2S) decays, and search for radiative decay to the {eta}{sub b}(1S) and {eta}{sub b}(2S) states.

Lees, J.P.; Poireau, V.; Prencipe, E.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Martinelli, M.; /INFN, Bari /Bari U.; Milanes, D.A.; /INFN, Bari; Palano, A.; Pappagallo, M.; /INFN, Bari /Bari U.; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Brown, D.N.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; /UC, Berkeley; Koch, H.; Schroeder, T.; /Ruhr U., Bochum; Asgeirsson, D.J.; Hearty, C.; /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /Frascati /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /Indian Inst. Tech., Guwahati /Harvard U. /Harvey Mudd Coll. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Paris U., VI-VII /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /INFN, Milan /Milan U. /INFN, Milan /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /INFN, Naples /Naples U. /NIKHEF, Amsterdam /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /INFN, Padua /INFN, Padua /Padua U. /Paris U., VI-VII /INFN, Perugia /Perugia U. /INFN, Pisa /Pisa U. /INFN, Pisa /Pisa, Scuola Normale Superiore /INFN, Pisa /Pisa U. /INFN, Pisa /INFN, Pisa /Pisa U. /INFN, Pisa /Princeton U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Southern Methodist U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas Nuclear Corp., Austin /Texas U., Dallas /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /Valencia U. /Victoria U. /Warwick U. /Wisconsin U., Madison

2011-08-15T23:59:59.000Z

305

Low Head, Vortex Induced Vibrations River Energy Converter  

DOE Green Energy (OSTI)

Vortex Induced Vibrations Aquatic Clean Energy (VIVACE) is a novel, demonstrated approach to extracting energy from water currents. This invention is based on a phenomenon called Vortex Induced Vibrations (VIV), which was first observed by Leonardo da Vinci in 1504AD. He called it ‘Aeolian Tones.’ For decades, engineers have attempted to prevent this type of vibration from damaging structures, such as offshore platforms, nuclear fuel rods, cables, buildings, and bridges. The underlying concept of the VIVACE Converter is the following: Strengthen rather than spoil vortex shedding; enhance rather than suppress VIV; harness rather than mitigate VIV energy. By maximizing and utilizing this unique phenomenon, VIVACE takes this “problem” and successfully transforms it into a valuable resource for mankind.

Bernitsas, Michael B.; Dritz, Tad

2006-06-30T23:59:59.000Z

306

Fluoride-containing wastewater converted to synthetic fluorspar  

Science Conference Proceedings (OSTI)

In the manufacture of uranium hexafluoride, sulfur hexafluoride, iodine pentafluoride, and antimony pentafluoride, the Allied Corporation's Metropolis Works (Metropolis, IL) generates approximately 250,000 gpd of process wastewater which contains substantial amounts of soluble fluoride. Most of the wastewater is also acidic. Alkaline waste and hydrated lime (calcium hydroxide) in a pair of neutralizers are used to precipitate the soluble fluoride as calcium fluoride. Due to the alkalinity, the material is considered a hazardous waste. The limited availability of land suitable for the construction of impoundment basins and the potential for eventual seepage from the basins presented a challenge to the management and technical staff at the Metropolis Works situation on-site. Efforts were directed toward developing a process to convert the calcium fluoride waste into a useful product. Excess lime waste could be converted to 90% CaF/sub 2/ by neutralizing the lime with hydrofluoric acid. The 90% CaF/sub 2/, closely resembling fluorspar, would be able to be used directly at other Allied plants as a substitute for natural fluorspar in the production of anhydrous hydrofluoric (AHF) acid. Engineering efforts to design a full-scale plant for the recovery of CaF/sub 2/ began in mid-1980. Construction of the plant begin in July, 1981. Since startup in mid-1982, the full scale recovery plant has been in continuous operation. Design capacity is 8000 tons/yr of synthetic fluorspar. The synthetic fluorspar is directly replacing an equivalent amount of imported natural fluorspar in the production of anhydrous hydrofluoric acid. Total cost to construct the CaF/sub 2/ recovery plant was $4.3 million. Currently realized cost savings of about $1 million/yr give the project an expected payback period of under five years.

Cipolla, A.J.; Shields, E.J.; Wickersham, C.P.; Toy, D.A.

1985-11-01T23:59:59.000Z

307

Loss mechanisms in turbine tip clearance flows  

E-Print Network (OSTI)

Numerical simulations of tip clearance ow have been carried out to dene the loss generation mechanisms associated with tip leakage in unshrouded axial turbines. Mix- ing loss between the leakage, which takes the form of a ...

Huang, Arthur (Arthur C.)

2011-01-01T23:59:59.000Z

308

Louisiana Wetland Loss Fact at Askives  

U.S. Energy Information Administration (EIA)

Louisiana Wetland Loss Fact? - Find Questions and Answers at Askives, the first startup that gives you an straight answer

309

Corona losses dependence from the conductor diameter  

Science Conference Proceedings (OSTI)

This paper presents possibility to decrease the corona power losses in overhead transmission lines. Corona power losses can be reduced by increasing the diameter of the conductor and used bundled conductors per phase. The objectives were to determine ... Keywords: corona model, critical disruptive voltage, electric discharge, electric field, power losses, transmission line

Isuf Krasniqi; Vjollca Komoni; Avni Alidemaj; Gazmend Kabashi

2011-10-01T23:59:59.000Z

310

Shield Losses in Medium-Voltage Cables  

Science Conference Proceedings (OSTI)

Utilities can substantially reduce cable costs and circulating current losses by optimizing the design of concentric neutral conductors for underground distribution cables and by configuring installed cables to minimize energy loss. This guide shows how to design neutral conductors for maximum cost-effectiveness and includes calculations of circulating current losses and ampacities for commonly used cables.

1987-12-14T23:59:59.000Z

311

Rotating electrical machines. Part 2: Methods for determining losses and efficiency of rotating electrical machinery from tests (excluding machines for traction vehicles)  

E-Print Network (OSTI)

Applies to d.c. machines and to a.c. synchronous and induction machines. The principles can be applied to other types of machines such as rotary converters, a.c. commutator motors and single-phase induction motors for which other methods of determining losses are used.

International Electrotechnical Commission. Geneva

1972-01-01T23:59:59.000Z

312

U-120: RSA SecurID Software Token Converter Unspecified Buffer Overflow  

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

0: RSA SecurID Software Token Converter Unspecified Buffer 0: RSA SecurID Software Token Converter Unspecified Buffer Overflow Vulnerability U-120: RSA SecurID Software Token Converter Unspecified Buffer Overflow Vulnerability March 8, 2012 - 7:00am Addthis PROBLEM: RSA SecurID Software Token Converter Unspecified Buffer Overflow Vulnerability PLATFORM: RSA SecurID Software Token Converter 2.x ABSTRACT: Successful exploitation may allow execution of arbitrary code. reference LINKS: Secunia Advisory SA48297 CVE-2012-0397 IMPACT ASSESSMENT: High Discussion: A vulnerability has been reported in RSA SecurID Software Token Converter, which can be exploited by malicious people to compromise a user's system. Impact: An unspecified error can be exploited to cause a buffer overflow. Solution: Update to version 2.6.1. Addthis Related Articles

313

MHK Technologies/Oceanlinx Mark 3 Wave Energy Converter | Open Energy  

Open Energy Info (EERE)

Oceanlinx Mark 3 Wave Energy Converter Oceanlinx Mark 3 Wave Energy Converter < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage Oceanlinx Mark 3 Wave Energy Converter.jpg Technology Profile Primary Organization Oceanlinx Project(s) where this technology is utilized *MHK Projects/GPP Namibia *MHK Projects/Greenwave Rhode Island Ocean Wave Energy Project *MHK Projects/Hawaii *MHK Projects/Oceanlinx Maui *MHK Projects/Port Kembla *MHK Projects/Portland Technology Resource Click here Wave Technology Type Click here Oscillating Water Column Technology Readiness Level Click here TRL 5/6: System Integration and Technology Laboratory Demonstration Technology Description The Oceanlinx Mark 3 Wave Energy Converter is a floating multi Oscilating Water Chamber Wave Energy Converter. The airflow generated by the OWC passes through a patented Denniss Auld turbine which converts the bidirectional airflow of the OWC to a unidirectional rotation of the axial flow turbine which in turn drives a generator.

314

Induction machine stray loss from inter-bar currents  

E-Print Network (OSTI)

Stray load loss refers generally to the sources of induction machine loss not accounted for by typical calculations of primary or secondary copper loss, no load core loss, or friction and windage loss. Harmonic rotor bar ...

Englebretson, Steven Carl

2009-01-01T23:59:59.000Z

315

On the Information Loss in Static Systems  

E-Print Network (OSTI)

In this work we give a concise definition of information loss from a system-theoretic point of view. Based on this definition, we analyze the information loss in static input-output systems subject to a continuous-valued input. For a certain class of multiple-input, multiple-output systems the information loss is quantified. An interpretation of this loss is accompanied by upper bounds which are simple to evaluate. Finally, a class of systems is identified for which the information loss is necessarily infinite. Quantizers and limiters are shown to belong to this class.

Geiger, Bernhard C

2011-01-01T23:59:59.000Z

316

Study of Heat Loss: Commercial and Residential  

E-Print Network (OSTI)

There is much savings involved in the prevention of heat loss. Many structures exhibit such loss. Much can be done to improve or minimize the heat loss in a structure. These include interior and exterior modifications. It has been shown that heat can move by means of convection, conduction, and radiation. Problems with heat loss can be due to moisture, and poor construction techniques. There is a beneficial cost savings involved in the prevention of heat loss. Prevention techniques include insulation, caulking, weather stripping, and double pane windows. There are tables available for one to reference and calculate the return on their investment or “payback tim”

Emmett Ientilucci

1995-01-01T23:59:59.000Z

317

An Integrated Onboard Charger and Accessary Power Converter for Plug-in Electric Vehicles  

SciTech Connect

Abstract: In this paper, an integrated onboard battery charger and accessary dc-dc converter for plug-in electric vehicles (PEVs) is presented. The idea is to utilize the already available traction drive inverters and motors of a PEV as the frond converter of the charger circuit and the transformer of the 14 V accessary dc-dc converter to provide galvanic isolation. The topology was verified by modeling and experimental results on a 5 kW charger prototype

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

2013-01-01T23:59:59.000Z

318

Design and characterization of a 0.35 micron CMOS voltage-to-current converter  

Science Conference Proceedings (OSTI)

This work presents the design and characterization of a CMOS voltage-to-current (V-I) converter with a current range from -100 ?A to 100 ?A. The V-I converter has a power consumption of approximately 0.6 mW and its final area was 0.022 mm2 ... Keywords: current reference, system on chip, voltage-to-current converter

Genival Mariano de Araujo; Heider Marconi G. Madureira; José Camargo da Costa

2009-08-01T23:59:59.000Z

319

Synchronization and chaos in spin-transfer-torque nano-oscillators coupled via a high speed Op Amp  

E-Print Network (OSTI)

We propose a system of two coupled spin-torque nano-oscillators (STNOs), one driver and another response, and demonstrate {using numerical studies} the synchronization of the response system to the frequency of the driver system. To this end we use a high speed operational amplifier in the form of a voltage follower which essentially isolates the drive system from the response system. We find the occurrence of 1:1 as w ell as 2:1 synchronization in the system, wherein the oscillators show limit cycle dynamics. An increase in power output is noticed when the two oscillators are locked in 1:1 synchronization. Moreover in the cro ssover region between these two synchronization dynamics we show the existence of chaotic dynamics in the slave system. The coupled dynamics under periodic forcing, using a small ac input current in addition to that of the dc part, is also studied. The slave oscillator is seen to retain its qualitative identity in the parameter space in spite of being fed in, at times, a chaotic signal. Such electrically coupled STNOs will be highly useful in fabricating commercial spin-valve oscillators with high power output, when integrated with other spintronic devices.

C. Sanid; S. Murugesh

2013-12-26T23:59:59.000Z

320

Collisionality Scaling of Main-ion Toroidal and Poloidal Rotation in Low Torque DIII-D Plasmas  

SciTech Connect

In tokamak plasmas with low levels of toroidal rotation, the radial electric fi eld Er is a combination of pressure gradient and toroidal and poloidal rotation components, all having similar magnitudes. In order to assess the validity of neoclassical poloidal rotation theory for determining the poloidal rotation contribution to Er , D? emission from neutral beam heated tokamak discharges in DIII-D [J.L. Luxon, Nucl. Fusion 42 , 614 (2002)] has been evaluated in a sequence of low torque (electron cyclotron resonance heating and balanced diagnostic neutral beam pulse) discharges to determine the local deuterium toroidal rotation velocity. By invoking the radial force balance relation the deuterium poloidal rotation can be inferred. It is found that the deuterium poloidal low exceeds the neoclassical value in plasmas with collisionality #23;#3; ?i < 0: 1, being more ion diamagnetic, and with a stronger dependence on collisionality than neoclassical theory predicts. At low toroidal rotation, the poloidal rotation contribution to the radial electric fi eld and its shear is signi cant. The eff ect of anomalous levels of poloidal rotation on the radial electric fi eld and cross fi eld heat transport is investigated for ITER parameters.

B A Grierson, et al

2013-05-10T23:59:59.000Z

Note: This page contains sample records for the topic "loss torque converter" 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

What are Ccf, Mcf, Btu, and therms? How do I convert prices in ...  

U.S. Energy Information Administration (EIA)

Natural Gas Conversion Calculator. Last updated: March 20, 2013. Other FAQs about Conversion & Equivalents. How do I convert between short tons and metric tons?

322

How do I convert between short tons and metric tons? - FAQ - U ...  

U.S. Energy Information Administration (EIA)

Other FAQs about Conversion & Equivalents. How do I convert between short tons and metric tons? How do I compare heating fuels?

323

Bibliography on overvoltage protection and insulation coordination of HVDC converter stations, 1979-1989  

Science Conference Proceedings (OSTI)

This bibliography is a listing of references on the subject of overvoltage protection and insulation coordination of HVDC converter stations, for the years 1979 through 1989.

Not Available

1991-04-01T23:59:59.000Z

324

Gasification is used to convert a solid feedstock, such as coal...  

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

can be captured and disposed of or converted to useful products more easily with gasification-based technologies compared to conventional combustion of solid feedstocks....

325

Index of /~jborwein/Expbook/Manuscript/Graphics files/please_convert  

E-Print Network (OSTI)

Index of /~jborwein/Expbook/Manuscript/Graphics files/please_convert. Icon Name Last modified Size Description. [DIR] Parent Directory - [DIR] ...

326

New Family of Multilevel Matrix Converters for Wind Power Applications: Final Report, July 2002 - March 2006  

DOE Green Energy (OSTI)

The goal of this project was to develop a new modular multilevel matrix converter for wind power applications and to demonstrate a working scale model in the laboratory.

Erickson, R.; Angkititrakul, S.; Almazeedi, K.

2006-12-01T23:59:59.000Z

327

Thermal analysis and testing of a vacuum insulated catalytic converter  

DOE Green Energy (OSTI)

Based on a recent US Environmental Protection Agency (EPA) study, about 95% of all trips start after a cold-soak period of 16 hours or less. By preserving the heat in the catalyst between trips, exhaust gases could be processed without warm-up delay and without the usual cold-start emissions. Vacuum insulation and phase-change thermal storage have been incorporated into a catalytic converter design to enhance its heat-retention time. Laboratory testing of a bench-scale prototype showed that a ``light off`` temperature (above 350 C) could be maintained during a 10-hour cold soak. Design improvements currently being tested should increase this heat-retention time to more than 16 hours. The thermal conductance of the vacuum insulation will be made continuously variable to prevent overheating and excessive thermal cycling. This approach to thermal management may be more durable and less costly than quick-heat methods using electric or fuel-fired preheat catalysts.

Burch, S D; Potter, T F; Keyser, M A; Benson, D K

1994-11-01T23:59:59.000Z

328

Converting acoustic energy into useful other energy forms  

SciTech Connect

Sonoluminescence is an off-equilibrium phenomenon in which the energy of a resonant sound wave in a liquid is highly concentrated so as to generate flashes of light. The conversion of sound to light represents an energy amplification of eleven orders of magnitude. The flashes which occur once per cycle of the audible or ultrasonic sound fields can be comprised of over one million photons and last for less 100 picoseconds. The emission displays a clocklike synchronicity; the jitter in time between consecutive flashes is less than fifty picoseconds. The emission is blue to the eye and has a broadband spectrum increasing from 700 nanometers to 200 nanometers. The peak power is about 100 milliWatts. The initial stage of the energy focusing is effected by the nonlinear oscillations of a gas bubble trapped in the liquid. For sufficiently high drive pressures an imploding shock wave is launched into the gas by the collapsing bubble. The reflection of the shock from its focal point results in high temperatures and pressures. The sonoluminescence light emission can be sustained by sensing a characteristic of the emission and feeding back changes into the driving mechanism. The liquid is in a sealed container and the seeding of the gas bubble is effected by locally heating the liquid after sealing the container. Different energy forms than light can be obtained from the converted acoustic energy. When the gas contains deuterium and tritium there is the feasibility of the other energy form being fusion, namely including the generation of neutrons.

Putterman, Seth J. (Sherman Oaks, CA); Barber, Bradley Paul (Northridge, CA); Hiller, Robert Anthony (Los Angeles, CA); Lofstedt, Ritva Maire Johanna (Los Angeles, CA)

1997-01-01T23:59:59.000Z

329

Measured and projected performance of plasma direct converters  

DOE Green Energy (OSTI)

Test results from two plasma direct converters and their predicted cost and performance on tandem mirror fusion reactors are present. The tests were done at high power density (approx. 70 W/cm/sup 2/) in steady state to simulate the predicted conditions in a reactor. A single stage unit and a two-stage unit of the Venetian blind type were tested at up to 100 kV and 6 kW for a total time of about 80 hours. Measured efficiencies, when projected to a reactor, are typically about 50% for a single stage unit and 60 to 70% for a two-stage unit, depending on the energy distribution of the ions, the degree of subdivision of the collectors, and on the gas pressure. The high ambipolar potential in tandem mirror devices makes this good efficiency possible. When radiatively cooled grids are used, the incident power density is limited to about 100 W/cm/sup 2/ by the thermionic emission of electrons.

Barr, W.L.; Moir, R.W.

1981-10-22T23:59:59.000Z

330

Analysis of electron transport in the plasma of thermionic converters  

DOE Green Energy (OSTI)

Electron transport coefficients of a gaseous ensemble are expressed analytically as function of density, and are expressed analytically as function of temperature up to an unknown function which has to be evaluated for each specific electron-neutral atom cross section. In order to complete the analytical temperature dependence one may introduce a polynomial expansion of the function or one may derive the temperature dependence of a set of coefficients, numbering thirteen for a third approximation transport evaluation, which completely determine the transport coefficients. The latter approach is used for determining the electron transport coefficients of a cesium plasma for any ion neutral composition and any temperature between 500/sup 0/K and 3500/sup 0/K. The relation between the transport coefficients of a fully and partly ionized gas is readily available and shows that, in the classical formalism, electron-ion and electron-neutral resistivities are not additive. The present form of the transport coefficients makes possible an accurate numerical integration of transport equations eliminating lengthy computations which are frequently inaccessible. It thus provides a detailed knowledge of spatial distribution of particle and energy transport and makes possible the determination of one of the three internal voltage drops, surface barrier, sheath and plasma, which are linked together experimentally by current density versus voltage characteristics of thermionic converters.

Stoenescu, M.L.; Heinicke, P.H.

1980-03-01T23:59:59.000Z

331

A local fitting algorithm for converting planar curves to  

E-Print Network (OSTI)

In this paper we present a local fitting algorithm for converting smooth planar curves to B-splines. For a smooth planar curve a set of points together with their tangent vectors are first sampled from the curve such that the connected polygon approximates the curve with high accuracy and inflexions are detected by the sampled data efficiently. Then, a G 1 continuous Bézier spline curve is obtained by fitting the sampled data with shape preservation as well as within a prescribed accuracy. Finally, the Bézier spline is merged into a C 2 continuous B-spline curve by subdivision and control points adjustment. The merging is guaranteed to be within another error bound and with no more inflexions than the Bézier spline. In addition to shape preserving and error control, this conversion algorithm also benefits that the knots are selected automatically and adaptively according to local shape and error bound. A few experimental results are included to demonstrate the validity and efficiency of the algorithm. Keywords: curve conversion; B-spline curve; cubic Bézier curve; knot selection; shape preserving 1.

unknown authors

2007-01-01T23:59:59.000Z

332

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

333

Device to convert the energy of a fluid in motion  

SciTech Connect

A device is disclosed to convert wave energy into mechanical energy, comprises a buoyant structure whose upper portion is in the region of wave action but whose lower section is below the region of wave action, so that the water adjacent the upper and lower sections of the structure has vertical movement relative to itself. This relative movement is used to rotate a vertical shaft having radially extending horizontal axles on which panels are pivotally mounted. Ballast and/or floats are used to impose on the panels a bias tending to maintain them horizontal. The relative movement of the water is used to impel fluid vertically relative to the panels in alternatingly opposite directions; and the bias imposed by the ballast and/or floats thus causes a planing wing action of the panels which impels the shaft in rotation in one direction regardless of the direction of the movement of the impelling fluid. The floating structure can rise and fall with the waves, in which case the blade are disposed at the lower end of the device, in the still water; or the device can be stationary in the water, in which case the blades are subject to a fluid such as the water itself or air impelled by the water, at the upper end of the device.

de la Roche Kerandraon, O.; Guillaume, P.; Paroldi, D.

1983-09-27T23:59:59.000Z

334

Power-Factor and Torque Calculation under Consideration of Cross Saturation of the Interior Permanent Magnet Synchronous Motor with Brushless Field Excitation  

SciTech Connect

This paper introduces a new method for calculating the power factor and output torque by considering the cross saturation between direct-axis (d-axis) and quadrature-axis (q-axis) of an interior permanent magnet synchronous motor (IPMSM). The conventional two-axis IPMSM model is modified to include the cross saturation effect by adding the cross-coupled inductance terms. This paper also contains the new method of calculating the cross-coupled inductance values as well as self-inductance values in d- and q-axes. The analyzed motor is a high-speed brushless field excitation machine that offers high torque per ampere per core length at low speed and weakened flux at high speed, which was developed for the traction motor of a hybrid electric vehicle. The conventional two-axis IPMSM model was modified to include the cross-saturation effect by adding the cross-coupled inductance terms Ldq and Lqd. By the advantage of the excited structure of the experimental IPMSM, the analyzing works were performed under two conditions, the highest and lowest excited conditions. Therefore, it is possible to investigate the cross-saturation effect when a machine has higher magnetic flux from its rotor. The following is a summary of conclusions that may be drawn from this work: (1) Considering cross saturation of an IPMSM offers more accurate expected values of motor parameters in output torque calculation, especially when negative d-axis current is high; (2) A less saturated synchronous machine could be more affected by the cross-coupled saturation effect; (3) Both cross-coupled inductances, L{sub qd} and L{sub dq}, are mainly governed by d-axis current rather than q-axis current; (4) The modified torque equation, can be used for the dynamic model of an IPMSM for developing a better control model or control strategy; and (5) It is possible that the brushless field excitation structure has a common magnetic flux path on both d- and q-axis, and as a result, the reluctance torque of the machine could be reduced.

Lee, Seong T [ORNL; Burress, Timothy A [ORNL; Tolbert, Leon M [ORNL

2009-01-01T23:59:59.000Z

335

Vehicle Technologies Office: Parasitic Loss Reduction  

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

Parasitic Loss Reduction Parasitic Loss Reduction Heavy vehicles lose a tremendous amount of energy to wind resistance and drag, braking, and rolling resistance. Such non-engine losses can account for an approximate 45% decrease in efficiency. Other sources of energy loss include: friction and wear in the power train, thermal (heat) loads, operation of auxiliary loads (air conditioning, heaters, refrigeration, etc.), and engine idling. The parasitic loss activity identifies methodologies that may reduce energy losses, and tests those in the laboratory. Promising technologies are then prototyped and tested onboard heavy vehicles. Once validated, technologies must be tested on-road to obtain durability, reliability, and life-cycle cost data for the developmental component and/or design strategy.

336

Adaptive stabilizing control of a power system through UPFC shunt and series converters  

Science Conference Proceedings (OSTI)

The dynamic performance of a power system can be improved by using additional controls in a unified power flow controller (UPFC). Self-tuning adaptive control of the voltage magnitude of the series converter and phase angle of shunt converter for stabilization ... Keywords: UPFC, adaptive control, on-line identification, pole - shifting control, power system stabilizing control

A. H. M. A. Rahim; E. P. Nowicki

2007-07-01T23:59:59.000Z

337

A 1-GSPS CMOS Flash A/D Converter for System-on-Chip Applications  

Science Conference Proceedings (OSTI)

Abstract: This paper presents an ultrafast CMOS flash A/D converter design and performance. Although the featured A/D converter is designed in CMOS, the performance is compatible to that of GaAs technology currently available. To achieve high-speed in ...

Jincheol Yoo; Kyusun Choi; Ali Tangel

2001-04-01T23:59:59.000Z

338

Improvements in power quality and efficiency with a new AC/DC high current converter  

Science Conference Proceedings (OSTI)

A very flexible AC/DC converter featuring high-output current, reduced voltage ripple and highly adjustable current control is described. The whole system consists of four stages and uses a proper switching technique in conjunction with a feedback control ... Keywords: AC/DC converter, FFT, electrical distribution systems, high direct-current, power quality

Francesco Muzi; Luigi Passacantando

2008-05-01T23:59:59.000Z

339

Sliding Mode Control of Boost Converter: Application to energy storage system via supercapacitors  

E-Print Network (OSTI)

Sliding Mode Control of Boost Converter: Application to energy storage system via supercapacitors», «Robust control», «Supercapacitor». Abstract Sliding mode control of boost converter is studied. In order of an energy storage system based on supercapacitors technology in order to regulate the output voltage. Given

Paris-Sud XI, Université de

340

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

Note: This page contains sample records for the topic "loss torque converter" 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

EPRI Power Flow to CIM Interface: Development of Power Flow to Common Information Model (CIM) Converter  

Science Conference Proceedings (OSTI)

IEEE has developed a Power Systems Application Data Dictionary (PSADD) for power system data and EPRI sponsored development of a CONVERTER program to convert PTI's PSS/E's data into this format. This project will develop the common data sources (CDSs) that translate the PSADD data to/from a Common Information Model (CIM)-structured database.

2002-11-27T23:59:59.000Z

342

Relation between verifiable random functions and convertible undeniable signatures, and new constructions  

Science Conference Proceedings (OSTI)

Verifiable random functions (VRF) and selectively convertible undeniable signature (SCUS) schemes were proposed independently in the literature. In this paper, we observe that they are tightly related. This directly yields several deterministic SCUS ... Keywords: selectively convertible undeniable signatures, standard model, verifiable random function

Kaoru Kurosawa; Ryo Nojima; Le Trieu Phong

2012-07-01T23:59:59.000Z

343

Structural And Economic Optimisation Of Bottom-Mounted Offshore Wind Energy Converters  

E-Print Network (OSTI)

A general overview is presented of the Opti-OWECS project. In several fields, support structure design, installation of the offshore wind energy converters, operation and maintenance, dynamics of the entire offshore wind energy converter, structural reliability considerations, etc., the study demonstrated new propositions which will contribute significantly to a mature offshore wind energy technology.

M. Kühn; W. A. A. M. Bierbooms; G.J.W. van Bussel; M. C. Ferguson; B. Göransson; T.T. Cockerill; R. Harrison; L.A. Harland; J. H. Vugts; R. Wiecherink; Kvaerner Turbin Ab

1999-01-01T23:59:59.000Z

344

Do Investment Banks' Relationships with Investors Impact Pricing? The Case of Convertible Bond Issues  

Science Conference Proceedings (OSTI)

This study examines the role of repeat interactions between placement agents (investment banks) and investors in the initial pricing of convertible bonds. Under the assumption that attracting repeat investors can reduce search frictions in primary issue ... Keywords: convertible bonds, corporate finance, securities issuance, underpricing

Brian J. Henderson; Heather Tookes

2012-12-01T23:59:59.000Z

345

Experimental studies and computer simulation of the control of energy transfer using inductor-converter bridges  

DOE Green Energy (OSTI)

An inductor-converter bridge (ICB) is a solid state DC-AC-DC power converter system for bidirectional, controllable, energy transfer between two coils. The ICB is suitable for supplying large pulsed power to such magnets as the superconducting equilibrium field coil of the proposed tokamak power reactors from another superconducting energy storage coil.

Hirano, M.; Kustom, R.L.

1984-03-01T23:59:59.000Z

346

Solar Power To Help Convert Carbon Dioxide Into Fuel : Renewable Energy News  

E-Print Network (OSTI)

Solar Power To Help Convert Carbon Dioxide Into Fuel : Renewable Energy News TUESDAY 25 MAY, 2010 | | Solar Power To Help Convert Carbon Dioxide Into Fuel by Energy Matters Microbiologist Derek Lovley dioxide into transportation fuels, with the help of special micro-organisms and solar power. The team

Lovley, Derek

347

Brief paper: Optimal switching instants for a switched-capacitor DC/DC power converter  

Science Conference Proceedings (OSTI)

We consider a switched-capacitor DC/DC power converter with variable switching instants. The determination of optimal switching instants giving low output ripple and strong load regulation is posed as a non-smooth dynamic optimization problem. By introducing ... Keywords: Control parametrization enhancing transform, Impulsive dynamical system, Power converter, Semi-infinite programming, Switched linear system

R. C. Loxton; K. L. Teo; V. Rehbock; W. K. Ling

2009-04-01T23:59:59.000Z

348

Association of Flyback Converters to Harvest Energy from Multiple Hydraulically Connected Biofuel Cells  

Science Conference Proceedings (OSTI)

Biofuel cells use catalysts (chemical, enzymatic or microbial) to convert chemical energy from organic substrates into electrical energy. This paper investigates energy harvesting from several low-power biofuel cells to power a load under several volts. ... Keywords: biofuel cell, energy harvesting, power management, flyback converter, low-power supply

Nicolas Degrenne, Marilyne Boileau, Florent Morel, Firas Khaled, Olivier Ondel, Francois Buret, Bruno Allard

2012-11-01T23:59:59.000Z

349

Developing and Simulation Research of the Control Model and Control Strategy of Static Frequency Converter  

Science Conference Proceedings (OSTI)

a control model and control strategy of static frequency converter (SFC) for pumped storage power plant unit is presented. Control strategy of static start-up and its mathematical model is discussed in detail. And based on the 42 poles of synchronous ... Keywords: Pumped Storage Power Plant, Static Frequency Converter, SFC, Commutation, Control

Deshun Wang; Lichun Zhang; Bo Yang; Guanjun Li; Yibin Tao; Jianzhong Fu; Jianfeng Li; Liantao Ji

2012-01-01T23:59:59.000Z

350

Observations of the mid-mantle discontinuity beneath Indonesia from S to P converted waveforms  

E-Print Network (OSTI)

Observations of the mid-mantle discontinuity beneath Indonesia from S to P converted waveforms a coherent discontinuity structure beneath Indonesia. Analysis of data recorded by three regional arrays from Indonesia from S to P converted waveforms, Geophys. Res. Lett., 33, L04302, doi:10.1029/2005GL025106. 1

Kawakatsu, Hitoshi

351

Multiport DC/DC Converter for Stand-alone Photovoltaic Lighting System with Battery Storage  

Science Conference Proceedings (OSTI)

Photovoltaic energy has nowadays an increased importance in electrical power applications. However, the output power provided via the photovoltaic conversion process depends on solar irradiation and temperature. Therefore a multiple-input DC/DC converter ... Keywords: Multiport DC/DC Converter, photovoltaic (PV), battery, charge/discharge

Shengyong Liu; Xing Zhang; Haibin Guo; Jun Xie

2010-06-01T23:59:59.000Z

352

Control of Parallel-Connected Bidirectional AC-DC Converters in Stationary Frame for Microgrid  

E-Print Network (OSTI)

Control of Parallel-Connected Bidirectional AC-DC Converters in Stationary Frame for Microgrid-- With the penetration of renewable energy in modern power system, microgrid has become a popular application worldwide. In this paper, parallel-connected bidirectional converters for AC and DC hybrid microgrid application

Teodorescu, Remus

353

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

354

Use of high-temperature, high-torque rheometry to study the viscoelastic properties of coal during carbonization  

SciTech Connect

When coal is heated in the absence of oxygen it softens at approximately 400 degrees C, becomes viscoelastic, and volatiles are driven off. With further heating, the viscous mass reaches a minimum viscosity in the range of 10{sup 3}-10{sup 5} Pa s and then begins to resolidify. A high-torque, high-temperature, controlled-strain rheometer with parallel plates has been used to study the theology during this process. Under shear, the viscosity of the softening mass decreases with increasing shear rate. During resolidification, the viscosity increases as C-C bond formation and physical interactions gives rise to an aromatic network, but, under shear, the network breaks apart and flows. This is viewed as a yielding of the structure. The higher the shear rate, the earlier the yielding occurs, such that if the shear rate is low enough, the structure is able to build. Also, further into resolidification lower shear rates are able to break the structure. It is proposed that resolidification occurs through the formation of aromatic clusters that grow and become crosslinked by non-covalent interactions. As the clusters grow, the amount of liquid surrounding them decreases and it is thought that the non-covalent interactions between clusters and liquid could decrease and the ability of growing clusters to move past each other increases, which would explain the weakening of the structure under shear. This work is part of a program of work aimed at attaining a greater understanding of microstructural changes taking place during carbonization for different coals, in order to understand the mechanisms that give rise to good quality cokes and coke oven problems such as excessive wall pressure.

Diaz, M.C.; Duffy, J.J.; Snape, C.E.; Steel, K.M. [University of Nottingham, Nottingham (United Kingdom)

2007-09-15T23:59:59.000Z

355

Reduce Radiation Losses from Heating Equipment  

Science Conference Proceedings (OSTI)

This DOE Industrial Technologies Program tip sheet describes how to save energy and costs by reducing expensive heat losses from industrial heating equipment, such as furnaces.

Not Available

2006-01-01T23:59:59.000Z

356

Analysis of TPV Network Losses (a Presentation)  

DOE Green Energy (OSTI)

This talk focuses on the theoretical analysis of electrical losses associated with electrically networking large numbers of TPV cells to produce high power TPV power generators.

DM DePoy; MW Dashiell; DD Rahner; LR Danielson; JE Oppenlander; JL Vell; RJ Wehrer

2004-12-08T23:59:59.000Z

357

Wetland loss dynamics in southwestern Barataria basin ...  

U.S. Energy Information Administration (EIA)

ABSTRACT We determined spatial associations of wetland loss rates in a 950-km2 study area in the southwestern Barataria basin of Louisiana's ...

358

Louisiana Coastal Land Loss Video Release  

U.S. Energy Information Administration (EIA)

Today, the U.S. Geological Survey National Wetlands Research Center is pleased to announce the release of a new Louisiana coastal land loss video, ...

359

Emissions and Experiences with E85 Converted Cars in the BEST Project |  

Open Energy Info (EERE)

Emissions and Experiences with E85 Converted Cars in the BEST Project Emissions and Experiences with E85 Converted Cars in the BEST Project Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Emissions and Experiences with E85 Converted Cars in the BEST Project Agency/Company /Organization: BioEthanol for Sustainable Transport Focus Area: Fuels & Efficiency Topics: Best Practices Website: www.best-europe.org/upload/BEST_documents/info_documents/Best%20report The BioEthanol for Sustainable Transport (BEST) project converted vehicles from petrol to E85, exploring the possibilities, advantages, and any difficulties. Several suggestions are presented for how converted cars may be incorporated into Swedish government financial incentives. How to Use This Tool This tool is most helpful when using these strategies: Shift - Change to low-carbon modes

360

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

SciTech Connect

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

None

2010-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "loss torque converter" 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

Compact self-contained electrical-to-optical converter/transmitter  

DOE Patents (OSTI)

An electrical-to-optical converter/transmitter is disclosed. A first optical receiver and a second optical receiver are provided for receiving a calibrate command and a power switching signal, respectively, from a remote processor. A third receiver is provided for receiving an analog electrical signal from a transducer. A calibrator generates a reference signal in response to the calibrate command. A combiner mixes the electrical signal with the reference signal to form a calibrated signal. A converter converts the calibrated signal to an optical signal. A transmitter transmits the optical signal to the remote processor. A primary battery supplies power to the calibrator, the combiner, the converter, and the transmitter. An optically-activated switch supplies power to the calibrator, the combiner, the converter, and the transmitter in response to the power switching signal. An auxiliary battery supplies power continuously to the switch means.

Seligmann, D.A.; Moss, W.C.; Valk, T.C.; Conder, A.D.

1992-12-31T23:59:59.000Z

362

Photo of the Week: Converting Solar Energy into Fuel | Department of Energy  

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

Converting Solar Energy into Fuel Converting Solar Energy into Fuel Photo of the Week: Converting Solar Energy into Fuel May 9, 2013 - 1:13pm Addthis In this photo, Brookhaven scientist Dmitry Polyansky examines a vial containing a specialized catalyst designed to help convert solar energy into fuel. Producing clean-burning hydrogen fuel from just sunlight and water requires custom-built catalysts for water oxidation -- the part of the water-splitting process that generates oxygen atoms. A tiny amount of the solid catalyst, developed in collaboration with the University of Houston, dissolves and turns the water that lovely shade of blue. | Photo courtesy of Brookhaven National Laboratory. In this photo, Brookhaven scientist Dmitry Polyansky examines a vial containing a specialized catalyst designed to help convert solar energy

363

Heat loss from an open cavity  

DOE Green Energy (OSTI)

Cavity type receivers are used extensively in concentrating solar thermal energy collecting systems. The Solar Total Energy Project (STEP) in Shenandoah, Georgia is a large scale field test for the collection of solar thermal energy. The STEP experiment consists of a large field array of solar collectors used to supplement the process steam, cooling and other electrical power requirements of an adjacent knitwear manufacturing facility. The purpose of the tests, conducted for this study, was to isolate and quantify the radiative, conductive, and convective components of total heat loss, and to determine the effects of operating temperature, receiver angle, and aperture size on cavity heat loss. An analytical model for radiative heat loss was developed and compared with two other methods used to determine radiative heat loss. A proposed convective heat loss correlation, including effects of aperture size, receiver operating temperature, and receiver angle is presented. The resulting data is a source to evaluate the STEP measurements.

McDonald, C.G. [California State Polytechnic Univ., Pomona, CA (United States). Coll. of Engineering

1995-12-01T23:59:59.000Z

364

Definition: Reduced Electricity Losses | Open Energy Information  

Open Energy Info (EERE)

Losses Losses Jump to: navigation, search Dictionary.png Reduced Electricity Losses Functions that provide this benefit could help manage peak feeder loads, reduced electricity throughput, locate electricity production closer to the load and ensure that voltages remain within service tolerances, while minimizing the amount of reactive power provided. These actions can reduce electricity losses by making the system more efficient for a given load served or by actually reducing the overall load on the system.[1] Related Terms load, electricity generation, reactive power, smart grid References ↑ SmartGrid.gov 'Description of Benefits' An inl LikeLike UnlikeLike You like this.Sign Up to see what your friends like. ine Glossary Definition Retrieved from "http://en.openei.org/w/index.php?title=Definition:Reduced_Electricity_Losses&oldid=502644

365

Wide input range DC-DC converter with digital control scheme  

E-Print Network (OSTI)

In this thesis analysis and design of a wide input range DC-DC converter is proposed along with a robust power control scheme. The proposed converter and its control is designed to be compatible to a fuel cell power source, which exhibits 2:1 voltage variation as well as a slow transient response. The proposed approach consists of two stages: a primary three-level boost converter stage cascaded with a high frequency, isolated boost converter topology, which provides a higher voltage gain and isolation from the input source. The function of the first boost converter stage is to maintain a constant voltage at the input of the cascaded DC-DC converter to ensure optimal performance characteristics with high efficiency. At the output of the first boost converter a battery or ultracapacitor energy storage is connected to take care of the fuel cell slow transient response (200 watts/min). The robust features of the proposed control system ensure a constant output DC voltage for a variety of load fluctuations, thus limiting the power being delivered by the fuel cell during a load transient. Moreover, the proposed configuration simplifies the power control management and can interact with the fuel cell controller. The simulation results and the experimental results confirm the feasibility of the proposed system.

Harfman Todorovic, Maja

2004-12-01T23:59:59.000Z

366

A bimetal and electret-based converter for thermal energy harvesting  

E-Print Network (OSTI)

This paper presents a new device able to turn thermal gradients into electricity by using a bimetal-based heat engine coupled to an electrostatic converter. A two-steps conversion is performed: (i) a curved bimetallic strip turns the thermal gradient into a mechanical movement (thermal-to-mechanical conversion) that is (ii) then converted into electricity thanks to an electret-based electrostatic converter (mechanical-to-electrical conversion). An output power up to 5.5uW on a hot source at 50{\\deg}C has already been reached, validating this new concept.

Boisseau, S; Monfray, S; Puscasu, O; Skotnicki, T

2012-01-01T23:59:59.000Z

367

A Rapid Loss Index for Tropical Cyclone Disasters in China  

Science Conference Proceedings (OSTI)

Disaster emergency response needs rapid estimation on disaster loss. In China it is of great importance to develop a loss index for rapidly assessing tropical cyclone (TC) disaster loss. In this paper, a new composite loss index for TC landing on China ... Keywords: Tropical Cyclone, Disaster, Loss Index, Rapid Loss Assessment

Ying Li; Weihua Fang

2012-06-01T23:59:59.000Z

368

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

E-Print Network (OSTI)

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

Hwang, J. George

369

Secretary Chu Announces Six Projects to Convert Captured CO2 Emissions from  

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

Announces Six Projects to Convert Captured CO2 Announces Six Projects to Convert Captured CO2 Emissions from Industrial Sources into Useful Products Secretary Chu Announces Six Projects to Convert Captured CO2 Emissions from Industrial Sources into Useful Products July 22, 2010 - 12:00am Addthis Washington, D.C. - U.S. Energy Secretary Steven Chu announced today the selections of six projects that aim to find ways of converting captured carbon dioxide (CO2) emissions from industrial sources into useful products such as fuel, plastics, cement, and fertilizers. Funded with $106 million from the American Recovery and Reinvestment Act -matched with $156 million in private cost-share -today's selections demonstrate the potential opportunity to use CO2 as an inexpensive raw material that can help reduce carbon dioxide emissions while producing useful by-products that Americans

370

DOE-TSPP-8-2013, Converting DOE Technical Standards to Voluntary Consensus  

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

-2013, Converting DOE Technical Standards to Voluntary -2013, Converting DOE Technical Standards to Voluntary Consensus Standards DOE-TSPP-8-2013, Converting DOE Technical Standards to Voluntary Consensus Standards Technical Standards Program Procedures (TSPP) - September 16, 2013 This procedure provides guidance on the conversion of DOE Technical Standards to Voluntary Consensus Standards (VCSs). This procedure applies to all Department of Energy (DOE) Headquarters and field organizations, management and operating contractors, and laboratories (hereafter referred to collectively as Technical Standards Program (TSP) participants) working to the requirements of the latest revision of DOE Order (O) 252.1A, Technical Standards Program. DOE-TSPP-8-2013, Converting DOE Technical Standards to Voluntary Consensus Standards

371

MHK Technologies/Uppsala Seabased AB Wave Energy Converter | Open Energy  

Open Energy Info (EERE)

AB Wave Energy Converter AB Wave Energy Converter < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage Uppsala Seabased AB Wave Energy Converter.jpg Technology Profile Primary Organization Uppsala University Division for Electricity Technology Resource Click here Wave Technology Type Click here Point Absorber - Floating Technology Readiness Level Click here TRL 5 6 System Integration and Technology Laboratory Demonstration Technology Description The system consists of a linear permanent magnet synchronous generator located on the sea floor The generator is connected directly via a line to a buoy on the surface There are no intermediate energy conversion steps thus the generator motion is the same as the buoy motion Several generators 3 today are connected to a marine substation where the voltage is converted to grid frequency transformed to higher voltage and transmitted to shore All electrical cables throughout the system are fixed i e there are no motions that subject the cables to bending moments

372

Compact self-contained electrical-to-optical converter/transmitter  

DOE Patents (OSTI)

A first optical receiver and a second optical receiver are provided for receiving a calibrate command and a power switching signal, respectively, from a remote processor. A third receiver is provided for receiving an analog electrical signal from a transducer. A calibrator generates a reference signal in response to the calibrate command. A combiner mixes the electrical signal with the reference signal to form a calibrated signal. A converter converts the calibrated signal to an optical signal. A transmitter transmits the optical signal to the remote processor. A primary battery supplies power to the calibrator, the combiner, the converter, and the transmitter. An optically-activated switch supplies power to the calibrator, the combiner, the converter, and the transmitter in response to the power switching signal. An auxiliary battery supplies power continuously to the switch.

Seligmann, Daniel A. (Manteca, CA); Moss, William C. (San Mateo, CA); Valk, Theodore C. (Livermore, CA); Conder, Alan D. (Tracy, CA)

1995-01-01T23:59:59.000Z

373

Converting mill buildings into housing : ways of working with brick walls  

E-Print Network (OSTI)

The mill buildings of New England add a unique dimension to the heritage and identity of the region. Today some of these buildings continue to function as the site of industry, others have been converted to commercial or ...

Pressman, Paul

1981-01-01T23:59:59.000Z

374

Research Projects to Convert Captured CO2 Emissions to Useful Products |  

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

Projects to Convert Captured CO2 Emissions to Useful Projects to Convert Captured CO2 Emissions to Useful Products Research Projects to Convert Captured CO2 Emissions to Useful Products July 6, 2010 - 1:00pm Addthis Washington, DC - Research to help find ways of converting into useful products CO2 captured from emissions of power plants and industrial facilities will be conducted by six projects announced today by the U.S. Department of Energy (DOE). The projects are located in North Carolina, New Jersey, Massachusetts, Rhode Island, Georgia, and Quebec, Canada (through collaboration with a company based in Lexington, Ky.) and have a total value of approximately $5.9 million over two-to-three years, with $4.4 million of DOE funding and $1.5 million of non-Federal cost sharing. The work will be managed by the

375

Secretary Chu Announces Six Projects to Convert Captured CO2 Emissions from  

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

Six Projects to Convert Captured CO2 Six Projects to Convert Captured CO2 Emissions from Industrial Sources into Useful Products Secretary Chu Announces Six Projects to Convert Captured CO2 Emissions from Industrial Sources into Useful Products July 22, 2010 - 1:00pm Addthis Washington, DC - U.S. Energy Secretary Steven Chu announced today the selections of six projects that aim to find ways of converting captured carbon dioxide (CO2) emissions from industrial sources into useful products such as fuel, plastics, cement, and fertilizers. Funded with $106 million from the American Recovery and Reinvestment Act -matched with $156 million in private cost-share -today's selections demonstrate the potential opportunity to use CO2 as an inexpensive raw material that can help reduce carbon dioxide emissions while producing useful by-products that Americans

376

Secretary Chu Announces Six Projects to Convert Captured CO2 Emissions from  

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

Six Projects to Convert Captured CO2 Six Projects to Convert Captured CO2 Emissions from Industrial Sources into Useful Products Secretary Chu Announces Six Projects to Convert Captured CO2 Emissions from Industrial Sources into Useful Products July 22, 2010 - 12:00am Addthis Washington, D.C. - U.S. Energy Secretary Steven Chu announced today the selections of six projects that aim to find ways of converting captured carbon dioxide (CO2) emissions from industrial sources into useful products such as fuel, plastics, cement, and fertilizers. Funded with $106 million from the American Recovery and Reinvestment Act -matched with $156 million in private cost-share -today's selections demonstrate the potential opportunity to use CO2 as an inexpensive raw material that can help reduce carbon dioxide emissions while producing useful by-products that Americans

377

DOE Will Convert Northeast Home Heating Oil Reserve to Ultra Low Sulfur  

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

DOE Will Convert Northeast Home Heating Oil Reserve to Ultra Low DOE Will Convert Northeast Home Heating Oil Reserve to Ultra Low Sulfur Distillate DOE Will Convert Northeast Home Heating Oil Reserve to Ultra Low Sulfur Distillate February 1, 2011 - 12:00pm Addthis Washington, DC - The current inventory of the Northeast Home Heating Oil Reserve will be converted to cleaner burning ultra low sulfur distillate to comply with new, more stringent fuel standards by some Northeastern states, the U.S. Department of Energy (DOE) said today. The State of New York and other Northeastern states are implementing more stringent fuel standards that require replacement of high sulfur (2,000 parts per million) heating oil to ultra low sulfur fuel (15 parts per million). As a result, DOE will sell the current inventory of the Northeast

378

Two U.S. University Research Reactors to be Converted From Highly Enriched  

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

U.S. University Research Reactors to be Converted From Highly U.S. University Research Reactors to be Converted From Highly Enriched Uranium to Low-Enriched Uranium Two U.S. University Research Reactors to be Converted From Highly Enriched Uranium to Low-Enriched Uranium April 11, 2005 - 11:34am Addthis WASHINGTON, D.C. - As part of the Bush administration's aggressive effort to reduce the amount of weapons-grade nuclear material worldwide, Secretary of Energy Samuel W. Bodman announced today that the Department of Energy (DOE) has begun to convert research reactors from using highly-enriched uranium (HEU) to low-enriched uranium fuel (LEU) at the University of Florida and Texas A&M University. This effort, by DOE's National Nuclear Security Administration (NNSA) and the Office of Nuclear Energy, Science and Technology, are the latest steps

379

Weekly Wrap-Up: Testing Wind Blades, Converting Carbon Emissions, and  

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

Weekly Wrap-Up: Testing Wind Blades, Converting Carbon Emissions, Weekly Wrap-Up: Testing Wind Blades, Converting Carbon Emissions, and Eco-Driving Weekly Wrap-Up: Testing Wind Blades, Converting Carbon Emissions, and Eco-Driving July 23, 2010 - 5:17pm Addthis Elizabeth Meckes Elizabeth Meckes Director of User Experience & Digital Technologies, Office of Public Affairs On Thursday, Secretary Chu announced six projects that aim to find ways of convert captured carbon dioxide (CO2) emissions from industrial sources into useful products. The innovative projects - funded with $106 million from the American Recovery and Reinvestment Act and matched with $156 million in private cost-share - will seek to use CO2 emissions from industrial sources to create useful products such as fuel, plastics, cement, and fertilizers. Find out more here.

380

DOE Will Convert Northeast Home Heating Oil Reserve to Ultra Low Sulfur  

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

Will Convert Northeast Home Heating Oil Reserve to Ultra Low Will Convert Northeast Home Heating Oil Reserve to Ultra Low Sulfur Distillate DOE Will Convert Northeast Home Heating Oil Reserve to Ultra Low Sulfur Distillate February 1, 2011 - 12:00pm Addthis Washington, DC - The current inventory of the Northeast Home Heating Oil Reserve will be converted to cleaner burning ultra low sulfur distillate to comply with new, more stringent fuel standards by some Northeastern states, the U.S. Department of Energy (DOE) said today. The State of New York and other Northeastern states are implementing more stringent fuel standards that require replacement of high sulfur (2,000 parts per million) heating oil to ultra low sulfur fuel (15 parts per million). As a result, DOE will sell the current inventory of the Northeast Home Heating Oil Reserve, a total of approximately 2 million barrels, and

Note: This page contains sample records for the topic "loss torque converter" 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

Progress on Converting a NIF Quad to Eight, Petawatt Beams for Advanced Radiography  

Science Conference Proceedings (OSTI)

We are converting a quad of NIF beamlines into eight, short-pulse (1-50 ps), petawatt-class beams for advanced radiography and fast ignition experiments. This paper describes progress toward completing this project.

Crane, J K

2009-10-19T23:59:59.000Z

382

High efficiency resonant dc/dc converter for solar power applications  

E-Print Network (OSTI)

This thesis presents a new topology for a high efficiency dc/dc resonant power converter that utilizes a resistance compression network to provide simultaneous zero voltage switching and near zero current switching across ...

Inam, Wardah

2013-01-01T23:59:59.000Z

383

Single-phase Converter-less Excitation Synchronous Stand-along Wind Power Generator System.  

E-Print Network (OSTI)

??In this thesis, a single-phase converter-less excitation synchronous stand-along wind power generator system is proposed. In order to simplify the system and improve the system… (more)

Lin, Chin-wei

2013-01-01T23:59:59.000Z

384

Radio frequency dc-dc converters : device characterization, topology evaluation, and design  

E-Print Network (OSTI)

High frequency power conversion is attractive for the opportunities it affords for improved performance. Dc-dc converters operating at high frequencies use smaller-valued energy storage elements, which tend to be physically ...

Leitermann, Olivia

2008-01-01T23:59:59.000Z

385

Design of ultra low power analog-to-digital converter for ambulatory EEG recording  

E-Print Network (OSTI)

Portable acquisition of biopotential signals requires the design of compact, energy efficient circuits and systems. Such systems typically include analog-to-digital converter for digitizing signals from AFE and feeding it ...

El-Damak, Dina Reda

2012-01-01T23:59:59.000Z

386

Design of a low-voltage low-power dc-dc HF converter  

E-Print Network (OSTI)

Many portable electronic applications could benefit from a power converter able to achieve high efficiency across wide input and output voltage ranges at a small size. However, it is difficult for many conventional power ...

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

2008-01-01T23:59:59.000Z

387

Design and evaluation of a very high frequency dc/dc converter  

E-Print Network (OSTI)

This thesis presents a resonant boost topology suitable for very high frequency (VHF, 30-300 MHz) dc-dc power conversion. The proposed design is a fixed frequency, fixed duty ratio resonant converter featuring low device ...

Pilawa-Podgurski, Robert C. N

2007-01-01T23:59:59.000Z

388

Single-inductor, multiple-output buck converter with parallel source transient recovery  

E-Print Network (OSTI)

To address the need for multiple regulated voltage supplies in electronic devices, this thesis presents a modeling and design study of a single-inductor, multiple-output (SIMO) DC-DC buck converter with parallel source ...

King, Charles Jackson, III

2009-01-01T23:59:59.000Z

389

A zero-crossing based pipelined analog-to-digital converter with supply voltage scalibility  

E-Print Network (OSTI)

A zero-crossing based pipelined analog-to-digital converter (ADC) has been designed and is fabricated in a 65nm CMOS process. The highly digital implementation characteristic of the zero-crossing detection technique enables ...

Lee, Sunghyuk

2010-01-01T23:59:59.000Z

390

High Voltage Thermal Battery Reliability Required to Equal Inverter-Converter Systems  

SciTech Connect

MC-583 and XMC-650 circuits, including associated pulse transformers, are compare with the inverter-converter system typical of present fuses. The required probabilities of thermal battery shorts and opens are determined.

1955-06-14T23:59:59.000Z

391

A single inductor dual input dual output DC-DC converter with hybrid supplies for solar energy harvesting applications  

Science Conference Proceedings (OSTI)

A single inductor dual input dual output (SIDIDO) DC-DC converter is proposed for solar energy harvesting applications. The converter supports hybrid power supplies from both the photovoltaic (PV) cells and the rechargeable battery. Apart from the conventional ... Keywords: DC-DC converter, MPPT, PV cells, dual-input-dual-output, energy harvesting, single inductor

Hui Shao; Chi-Ying Tsui; Wing-Hung Ki

2009-08-01T23:59:59.000Z

392

Direct connection of series self-excited generators and HVDC converters  

Science Conference Proceedings (OSTI)

An alternative and simpler solution is proposed for the direct connection of generators to HVdc converters. The generator exciter windings are connected in series with the output of the HVdc converter and take the place of the conventional smoothing reactor. Existing steady state and time domain simulation programs are modified to represent the behavior of the series direct connection scheme. It is shown that series excitation extends naturally the power transmission capability and permits fast fault clearances.

Arrillaga, J.; Macdonald, S.J.; Watson, N.R.; Watson, S. (Univ. Canterbury, Christchurch (New Zealand))

1993-10-01T23:59:59.000Z

393

Why 25?? and Y-12 mercury losses  

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

"25"? and Y-12 mercury losses Recently I learned something new regarding the "shortcut names" or code names for uranium-235 and plutonium-239. It seems the codes used to discuss...

394

Corona losses in HVdc bipolar lines  

SciTech Connect

The problem related to the prediction of corona losses in HVdc bipolar lines has been solved, in the past, by means of semi-empirical monomial formulae. However, the proposed formulae that are simpler to use do not always give adequate calculation precision, while the formulae that provide the closest results require implicit functions of different complexity, which are difficult to apply; moreover, it is not possible to understand clearly what influence the variations of the different line parameters have on the losses themselves. The new monomial semi-empirical relationship, proposed to predict the corona losses in HVdc bipolar lines, is very simple to use; it highlights the dependence of power losses due to the corona effect by the different line parameters. The formula has been developed by elaborating a considerable amount of available experimental data.

Corbellini, U.; Pelacchi, P. [Univ. of Pisa (Italy). Dept. of Electric Systems and Automation

1996-07-01T23:59:59.000Z

395

Trough Receiver Heat Loss Testing (Presentation)  

DOE Green Energy (OSTI)

This presentation describes the design, fabrication, and qualification of an experimental capability for thermal loss testing of full-size trough receiver elements; and the testing on a variety of receivers.

Lewandowski, A.; Feik, C.; Hansen, R.; Phillips, S.; Bingham, C.; Netter, J.; Forristal, R.; Burkholder, F.; Meglan, B.; Wolfrum, E.

2006-02-01T23:59:59.000Z

396

Mass-loss from Red Giants  

E-Print Network (OSTI)

Although much is known about the nature of winds from hot stars and giants and supergiants with spectral types earlier than K, there is still much to be learned regarding the mass-loss process in cool, late-type stars. We will review the current state of research, with particular reference to observations and modelling of mass-loss from giant stars in symbiotic systems.

Brian Espey; Cian Crowley

2008-03-07T23:59:59.000Z

397

Design considerations for DC-DC converters in fuel cell systems  

E-Print Network (OSTI)

Rapidly rising fossil fuel costs along with increased environmental awareness has encouraged the development of alternative energy sources. Such sources include fuel cells, wind, solar and ocean tide power. Among them, fuel cells have received increased interest in the recent years. This is mainly due to their high efficiency, modularity, and simple construction. However, due to their low output voltage and wide variation from no load to full load, a power electronics converter is required to interface the fuel cell with its loads. This dissertation focuses on developing a set of considerations that will assist designers of the power electronics converter in the design and optimization of the system. These design considerations are obtained analytically and verified experimentally and allow obtaining an efficient and stable fuel cell – power converter system. In addition to the design guidelines this dissertation presents new power converter topologies that do not require the use of transformers to achieve a large voltage gain. Further a new modular fuel cell power converter system that divides the fuel cell stack to optimize power generation is proposed. It is shown by means of mathematical analysis and experimental prototypes that the proposed solutions contribute to the reduction of size and cost of the power converter as well to increase the efficiency of the system.

Palma Fanjul, Leonardo Manuel

2006-12-01T23:59:59.000Z

398

100kW Energy Transfer Multiplexer Power Converter Prototype Development Project  

DOE Green Energy (OSTI)

Project Final Report for "100kW Energy Transfer Multiplexer Power Converter Prototype Development Project" prepared under DOE grant number DE-FG36-03GO13138. This project relates to the further development and prototype construction/evaluation for the Energy Transfer Multiplexer (ETM) power converter topology concept. The ETM uses a series resonant link to transfer energy from any phase of a multiphase input to any phase of a multiphase output, converting any input voltage and frequency to any output voltage and frequency. The basic form of the ETM converter consists of an eight (8)-switch matrix (six phase power switches and two ground power switches) and a series L-C resonant circuit. Electronic control of the switches allows energy to be transferred in the proper amount from any phase to any other phase. Depending upon the final circuit application, the switches may be either SCRs or IGBTs. The inherent characteristics of the ETM converter include the following: Power processing in either direction (bidirectional); Large voltage gain without the need of low frequency magnetics; High efficiency independent of output load and frequency; Wide bandwidth with fast transient response and; Operation as a current source. The ETM is able to synthesize true sinusoidal waveforms with low harmonic distortions. For a low power PM wind generation system, the ETM has the following characteristics and advantages: It provides voltage gain without the need of low frequency magnetics (DC inductors) and; It has constant high efficiency independent of the load. The ETM converter can be implemented into a PM wind power system with smaller size, reduced weight and lower cost. As a result of our analyses, the ETM offers wind power generation technology for the reduction of the cost and size as well as the increase in performance of low power, low wind speed power generation. This project is the further theoretical/analytical exploration of the ETM converter concept in relationship to PM wind power generator applications in the 100kW and under power range. The theoretical/analytical and bench scale work focuses on simplifying the basic ETM converter topology (in terms of parts count and complexity) for the specific application of the low power PM system. The project goals and objectives were for Spellman HV will develop a 100kW prototype ETM power converter based on paralleled lower ratings converters. The proposed configuration of this prototype is a 100kW rated converter comprised of four (4) 34kW rated modules connected in parallel (the fourth converter is included to demonstrate N+1 fault tolerance). This approach is more viable as there is lower technological risk involved in developing a 34kW-rated converter than a single 100kW unit. The modular system approach should have a lower deployment and service cost over a single unit system, because of the economics of scale (smaller units at a higher volume means lower manufacturing cost) and because of improved serviceability (a non-redundant power system with one failed module will still operate at a lower power level). There is also the added benefit that greater commercial application and acceptance should be achieved by having a modular system available in which fault tolerance (N+1 or 2N) is a feature. This modular approach would allow the output power to be increased by adding more paralleled converters. Thus, the maximum output power of the overall power system is a function of the interconnection medium (the hot swap connection subsystem), rather than the ratings of a single module. The project was implemented with Spellman HV acting as the program management and production assembly and test facility; The Baker Company acting as a technical consultant and resource when required; and dtm Associates acting as the design/development resource for the hardware development of the 100kW ETM converter prototype.

S. Merrill Skeist; Richard H. (Dick) Baker; Anthony G.P. Marini; DOE Project Officer - Keith Bennett

2006-03-21T23:59:59.000Z

399

Support vector machines with the ramp loss and the hard margin loss  

E-Print Network (OSTI)

Nov 4, 2008 ... Despite the fact that training SVM with the robust loss functions requires the solution of a quadratic mixed-integer program (QMIP) and is ...

400

FINAL REPORT OF RESEARCH ON CuxS/ (Cd,Zn)S PHOTOVOLTAIC SOLAR ENERGY CONVERTERS 3/77 - 9/79  

E-Print Network (OSTI)

Cu X S/(Cd,Zn)S PHOTOVOLTAIC SOLAR ENERGY CONVERTERS 3/77 -of Research on Photovoltaic Solar Energy Converters CuxSI(Cd

Chin, B.L.

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "loss torque converter" 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

On proton CT reconstruction using MVCT-converted virtual proton projections  

Science Conference Proceedings (OSTI)

Purpose: To describe a novel methodology of converting megavoltage x-ray projections into virtual proton projections that are otherwise missing due to the proton range limit. These converted virtual proton projections can be used in the reconstruction of proton computed tomography (pCT). Methods: Relations exist between proton projections and multispectral megavoltage x-ray projections for human tissue. Based on these relations, these tissues can be categorized into: (a) adipose tissue; (b) nonadipose soft tissues; and (c) bone. These three tissue categories can be visibly identified on a regular megavoltage x-ray computed tomography (MVCT) image. With an MVCT image and its projection data available, the x-ray projections through heterogeneous anatomy can be converted to the corresponding proton projections using predetermined calibration curves for individual materials, aided by a coarse segmentation on the x-ray CT image. To show the feasibility of this approach, mathematical simulations were carried out. The converted proton projections, plotted on a proton sinogram, were compared to the simulated ground truth. Proton stopping power images were reconstructed using either the virtual proton projections only or a blend of physically available proton projections and virtual proton projections that make up for those missing due to the range limit. These images were compared to a reference image reconstructed from theoretically calculated proton projections. Results: The converted virtual projections had an uncertainty of {+-}0.8% compared to the calculated ground truth. Proton stopping power images reconstructed using a blend of converted virtual projections (48%) and physically available projections (52%) had an uncertainty of {+-}0.86% compared with that reconstructed from theoretically calculated projections. Reconstruction solely from converted virtual proton projections had an uncertainty of {+-}1.1% compared with that reconstructed from theoretical projections. If these images are used for treatment planning, the average proton range uncertainty is estimated to be less than 1.5% for an imaging dose in the milligray range. Conclusions: The proposed method can be used to convert x-ray projections into virtual proton projections. The converted proton projections can be blended with existing proton projections or can be used solely for pCT reconstruction, addressing the range limit problem of pCT using current therapeutic proton machines.

Wang Dongxu; Mackie, T. Rockwell; Tome, Wolfgang A. [Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53705 and Department of Radiation Oncology, University of Iowa Hospitals and Clinics, Iowa City, Iowa 52242 (United States); Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53705 and Morgridge Institute of Research, University of Wisconsin, Madison, Wisconsin 53715 (United States); Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53705 and Oncophysics Institute, Albert Einstein College of Medicine, Yeshiva University, Bronx, New York 10461 (United States)

2012-06-15T23:59:59.000Z

402

Glass material oxidation and dissolution system: Converting miscellaneous fissile materials to glass  

SciTech Connect

The cold war and the development of nuclear energy have resulted in significant inventories of miscellaneous fissile materials (MFMs). MFMs include (1) plutonium scrap and residue, (2) miscellaneous spent nuclear fuel (SNF), (3) certain hot cell wastes, and (4) many one-of-a-kind materials. Major concerns associated with the long-term management of these materials include: safeguards and nonproliferation issues; health, environment, and safety concerns. waste management requirements; and high storage costs. These issues can be addressed by converting the MFMs to glass for secure, long-term storage or repository disposal; however, conventional glass-making processes require oxide-like feed materials. Converting MFMs to oxide-like materials with subsequent vitrification is a complex and expensive process. A new vitrification process has been invented, the Glass Material Oxidation and Dissolution System (GMODS), which directly converts metals, ceramics, and amorphous solids to glass; oxidizes organics with the residue converted to glass; and converts chlorides to borosilicate glass and a secondary sodium chloride (NaCl) stream. Laboratory work has demonstrated the conversion of cerium (a plutonium surrogate), uranium, Zircaloy, stainless steel, multiple oxides, and other materials to glass. However, significant work is required to develop GMODS further for applications at an industrial scale. If implemented, GMODS will provide a new approach to manage these materials.

Forsberg, C.W.; Ferrada, J.J.

1996-03-19T23:59:59.000Z

403

MHK Technologies/Multi Absorbing Wave Energy Converter MAWEC | Open Energy  

Open Energy Info (EERE)

Absorbing Wave Energy Converter MAWEC Absorbing Wave Energy Converter MAWEC < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage Multi Absorbing Wave Energy Converter MAWEC.jpg Technology Profile Primary Organization Leancon Wave Energy Project(s) where this technology is utilized *MHK Projects/Leancon Real Sea Test Technology Resource Click here Wave Technology Type Click here Oscillating Wave Surge Converter Technology Readiness Level Click here TRL 1-3: Discovery / Concept Definition / Early Stage Development & Design & Engineering Technology Description MAWEC is an OWC wave energy converter that works differently from other OWCs in that it concurrently utilizes pressure and suck. This gives the wanted effect that the vertical force on the WEC is zero when the WEC stretches over more than one wave length. The device is V-shaped and oriented perpendicular to wave direction. The device consists of a number of vertical air tubes, and when a wave passes, air is pushed into a pressure channel that sucks air out of the suck channel. During one wave period each tube (120 in total) goes through a sequence where air is first pushed into a pressure channel when the wave is rising and is later sucked from the pressure channel when the wave is falling. In this situation there is constant pressure in the pressure channel and the air flow through the turbines is constant.

404

Atom-molecule conversion with particle losses  

E-Print Network (OSTI)

Based on the mean-field approximation and the phase space analysis, we study the dynamics of an atom-molecule conversion system subject to particle loss. Starting from the many-body dynamics described by a master equation, an effective nonlinear Schr\\"odinger equation is introduced. The classical phase space is then specified and classified by fixed points. The boundary, which separate different dynamical regimes have been calculated and discussed. The effect of particle loss on the conversion efficiency and the self-trapping is explored.

B. Cui; L. C. Wang; X. X. Yi

2011-03-01T23:59:59.000Z

405

AC Loss Measurements with a Cryocooled Sample  

SciTech Connect

A new cryostat cooled by a closed-cycle Cryomech GB-37 cryocooler for superconductor measurements at temperatures down to 20 K is described. The sample is conductively coupled to the cold stage so as to minimize vibration and thermal stresses. AC losses have been measured calorimetrically in several HTSC coils that have been wound to simulate sub-scale transformer winding pairs. Stable temperatures down to 20 K were reached on these coils, allowing measurements at practical levels of ac current and I{sub c}. By using short ac current pulses, losses on individual turns could be resolved. Results are reported mainly to showcase the apparatus, measurement procedure and analytical approach.

Schwenterly, S.W.

2001-02-15T23:59:59.000Z

406

Have Disaster Losses Increased Due to Anthropogenic Climate Change?  

Science Conference Proceedings (OSTI)

The increasing impact of natural disasters over recent decades has been well documented, especially the direct economic losses and losses that were insured. Claims are made by some that climate change has caused more losses, but others assert ...

Laurens M. Bouwer

2011-01-01T23:59:59.000Z

407

Scientists Discover how Bacteria Convert Mercury to Toxic Form | U.S. DOE  

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

Scientists Discover how Bacteria Convert Mercury to Toxic Form Scientists Discover how Bacteria Convert Mercury to Toxic Form Biological and Environmental Research (BER) BER Home About Research Facilities Science Highlights Searchable Archive of BER Highlights External link Benefits of BER Funding Opportunities Biological & Environmental Research Advisory Committee (BERAC) News & Resources Contact Information Biological and Environmental Research U.S. Department of Energy SC-23/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3251 F: (301) 903-5051 E: sc.ber@science.doe.gov More Information » April 2013 Scientists Discover how Bacteria Convert Mercury to Toxic Form Two genes responsible for mercury methylation identified. Print Text Size: A A A Subscribe FeedbackShare Page Click to enlarge photo. Enlarge Photo

408

DC to DC power converters and methods of controlling the same  

DOE Patents (OSTI)

A power generation system configured to provide direct current (DC) power to a DC link is described. The system includes a first power generation unit configured to output DC power. The system also includes a first DC to DC converter comprising an input section and an output section. The output section of the first DC to DC converter is coupled in series with the first power generation unit. The first DC to DC converter is configured to process a first portion of the DC power output by the first power generation unit and to provide an unprocessed second portion of the DC power output of the first power generation unit to the output section.

Steigerwald, Robert Louis; Elasser, Ahmed; Sabate, Juan Antonio; Todorovic, Maja Harfman; Agamy, Mohammed

2012-12-11T23:59:59.000Z

409

Design considerations for a thermophotovoltaic energy converter using heat pipe radiators  

DOE Green Energy (OSTI)

The purpose of this paper is to discuss concepts for using high temperature heat pipes to transport energy from a heat source to a thermophotovoltaic (TPV) converter. Within the converter, the condenser portion of each heat pipe acts as a photon radiator, providing a radiant flux to adjacent TPV cells, which in turn create electricity. Using heat pipes in this way could help to increase the power output and the power density of TPV systems. TPV systems with radiator temperatures in the range of 1,500 K are expected to produce as much as 3.6 W/cm{sup 3} of heat exchanger volume at an efficiency of 20% or greater. Four different arrangements of heat pipe-TPV energy converters are considered. Performance and sizing calculations for each of the concepts are presented. Finally, concerns with this concept and issues which remain to be considered are discussed.

Ashcroft, J.; DePoy, D. [Lockheed Martin Corp., Schenectady, NY (United States)

1997-06-01T23:59:59.000Z

410

Experience in the installation of a microprocessor system for controlling converter units of the Vyborg substation  

SciTech Connect

The experience in the installation of modern digital systems for controlling converter units at the Vyborg converter substation on the basis of advanced microprocessor devices is considered. It is shown that debugging of a control and protection system on mathematical and physical models does not guarantee optimum control of actual converter devices. Examples of advancing the control and protection system are described, the necessity for which has become obvious in tests of actual equipment. Comparison of oscillograms of processes before optimization of the control system and after its optimization and adjustment shows that the digital control system makes it possible to improve substantially the algorithms of control and protection in the short term and without changing the hardware component.

Gusakovskii, K. B.; Zmaznov, E. Yu.; Katantsev, S. V.; Mazurenko, A. K.; Mestergazi, V. A.; Prochan, G. G.; Funtikova, S. F. [High Voltage Direct Current Power Transmission Research Institute (NIIPT) (Russian Federation)

2006-01-15T23:59:59.000Z

411

SUBCONTRACT REPORT: DC-DC Converter for Fuel Cell and Hybrid Vehicles  

DOE Green Energy (OSTI)

The goal of this project is to develop and fabricate a 5kW dc-dc converter with a baseline 14V output capability for fuel cell and hybrid vehicles. The major objectives for this dc-dc converter technology are to meet: Higher efficiency (92%); High coolant temperature,e capability (105 C); High reliability (15 Years/150,000miles); Smaller volume (5L); Lower weight (6kg); and Lower cost ($75/kW). The key technical challenge for these converters is the 105 C coolant temperatures. The power switches and magnetics must be designed to sustain these operating temperatures reliably, without a large cost/mass/volume penalty.

Marlino, Laura D [ORNL; Zhu, Lizhi [Ballard Power Systems/Siemens VDO

2007-07-01T23:59:59.000Z

412

An 8-bit current mode ripple folding analog to digital converter  

E-Print Network (OSTI)

Design of an 8-bit current mode, ripple-folding analog to digital (A/D) converter is discussed. The ripple folding technique and the possible implementations in different process technologies are summarized. To have an A/D converter compatible with the standard CMOS processes, the switched current technique is used for the implementation. The architecture is a cascade of 8 minimum and maximum detectors pipelined by 7 current memories. The A/D converter, which is designed in TSMC 0.35 []m CMOS technology, achieves 8 bits of resolution at a conversion rate of 100 MHz with an SFDR of 62 dB. The total power consumption by the analog circuitry is 120mW, more than half of which is dissipated by the 8 current comparators. The achieved INL and DNL values are less than 0.4 LSB.

Dinc, Huseyin

2002-01-01T23:59:59.000Z

413

ORNL analysis predicts losses from extreme weather damage could...  

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

ORNL analysis predicts losses from extreme weather damage could double by 2050 Researcher tackles unprecedented county-by-county economic loss forecast Research in impacts,...

414

Federal Offshore--Gulf of Mexico Natural Gas Extraction Loss...  

Annual Energy Outlook 2012 (EIA)

Pages: Extraction Loss of Natural Gas at Processing Plants (Summary) Federal Offshore Gulf of Mexico Natural Gas Plant Processing Extraction Loss of Natural Gas at...

415

Aerodynamic Losses and Heat Transfer in a Blade Cascade with...  

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

Aerodynamic Losses and Heat Transfer in a Aerodynamic Losses and Heat Transfer in a Blade Cascade with 3 Blade Cascade with 3 - - D D Endwall Endwall Contouring Contouring...

416

South Dakota Natural Gas Extraction Loss (Million Cubic Feet...  

U.S. Energy Information Administration (EIA) Indexed Site

View History: Annual Download Data (XLS File) South Dakota Natural Gas Extraction Loss (Million Cubic Feet) South Dakota Natural Gas Extraction Loss (Million Cubic Feet) Decade...

417

Mobile device protection from loss and capture  

Science Conference Proceedings (OSTI)

Mobile devices play a critical role in assistive environments. How to authenticate and secure communications among them has become more important especially against loss and capture of the devices. In this paper, we present an approach to protect signing ... Keywords: assistive environment, authentication, digital signature, forward security, mobile device

Zhengyi Le; Yi Ouyang; Yurong Xu; Fillia Makedon

2008-07-01T23:59:59.000Z

418

Spin-torque diode spectrum of ferromagnetically coupled (FeB/CoFe)/Ru/(CoFe/FeB) synthetic free layer  

SciTech Connect

We investigated systematically the spin torque diode spectrum of a ferromagnetically coupled (FeB/CoFe)/Ru/(CoFe/FeB) synthetic free layer in an MgO-based magnetic tunnel junction. In the spectra, we observed single peaks shifted to higher frequency with increasing the in-plane magnetic fields, as expected from the ferromagnetic resonance of the FeB/CoFe adjacent to the MgO tunnel barrier. On the other hand, under the perpendicular fields, we observed several peaks below 6 GHz and around 10 GHz, which were rather insensitive to the field. These behaviors are different from our simple calculation taking account the interlayer coupling, suggesting that the excitation of magnetizations occurs in a complicated manner for the synthetic free layers.

Bang, Do; Taniguchi, Tomohiro; Kubota, Hitoshi; Yorozu, Takehiko; Imamura, Hiroshi; Yakushiji, Kay; Fukushima, Akio; Yuasa, Shinji; Ando, Koji [National Institute of Advanced Industrial Science and Technology (AIST), Central 2, Umezono 1-1-1, Tsukuba, Ibaraki 305-8568 (Japan)

2012-04-01T23:59:59.000Z

419

Chemical reactor for converting a first material into a second material  

Science Conference Proceedings (OSTI)

A chemical reactor and method for converting a first material into a second material is disclosed and wherein the chemical reactor is provided with a feed stream of a first material which is to be converted into a second material; and wherein the first material is combusted in the chemical reactor to produce a combustion flame, and a resulting gas; and an electrical arc is provided which is passed through or superimposed upon the combustion flame and the resulting gas to facilitate the production of the second material.

Kong, Peter C

2012-10-16T23:59:59.000Z

420

Evolution of the CERN Power Converter Function Generator/Controller for Operation in Fast Cycling Accelerators  

E-Print Network (OSTI)

Power converters in the LHC are controlled by the second generation of an embedded computer known as a Function Generator/Controller (FGC2). Following the success of this control system, new power converter installations at CERN will be based around an evolution of the design – a third generation called FGC3. The FGC3 will initially be used in the PS Booster and Linac4. This paper compares the hardware of the two generations of FGC and details the decisions made during the design of the FGC3.

Calcoen, D; Semanaz, PF

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "loss torque converter" 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

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

422

Chemical reactor and method for chemically converting a first material into a second material  

DOE Patents (OSTI)

A chemical reactor and method for converting a first material into a second material is disclosed and wherein the chemical reactor is provided with a feed stream of a first material which is to be converted into a second material; and wherein the first material is combusted in the chemical reactor to produce a combustion flame, and a resulting gas; and an electrical arc is provided which is passed through or superimposed upon the combustion flame and the resulting gas to facilitate the production of the second material.

Kong, Peter C. (Idaho Falls, ID)

2008-04-08T23:59:59.000Z

423

Converter Program: PSADD Dictionary for Dynamics Model, Version 2.0  

Science Conference Proceedings (OSTI)

This manual contains a listing of the PSADD dictionary for PSS/E dynamics models. The format of this dictionary is the same as that used for the "main" PSADD. Wherever possible, dictionary names and data types are the same as those used in the "main" PSADD. Please note that not all of the PSS/E dynamics models have been included in this dictionary and are convertible by the CONVERTER program. EPRI advisors and PTI engineers selected the models for inclusion based on the perceived "usefulness" of the mode...

2000-07-13T23:59:59.000Z

424

Evaluation of the effectiveness of shielding and filtering of HVDC converter stations  

Science Conference Proceedings (OSTI)

The electromagnetic interference (EMI) generated by the periodic turn-on and turn-off of the valves is an important consideration in the design of HVDC converter stations. Remedial measures such as shielding the valve hall and filtering have been used in order to reduce the interference levels to acceptable values. The application of recently-developed Numerical Electromagnetic Code (NEC) to the problem of EMI from HVDC converter stations is investigated in this paper, with particular emphasis on evaluating the effectiveness of valve hall shielding and filtering.

Dallaire, R.D.; Maruvada, P.S.

1989-04-01T23:59:59.000Z

425

Design and operating experience of an ac-dc power converter for a superconducting magnetic energy storage unit  

DOE Green Energy (OSTI)

The design philosophy and the operating behavior of a 5.5 kA, +-2.5 kV converter, being the electrical interface between a high voltage transmission system and a 30 MJ superconducting coil, are documented in this paper. Converter short circuit tests, load tests under various control conditions, dc breaker tests for magnet current interruption, and converter failure modes are described.

Boenig, H.J.; Nielsen, R.G.; Sueker, K.H.

1984-01-01T23:59:59.000Z

426

SoC Energy Savings = Reduce+Reuse+Recycle: A Case Study Using a 660MHz DC-DC Converter with Integrated Output Filter  

E-Print Network (OSTI)

SoC Energy Savings = Reduce+Reuse+Recycle: A Case Study Using a 660MHz DC-DC Converter will use all 3 of these techniques in the DC-DC buck converter shown in Fig. 1. Energy reduction of the DC-DC converter front-end drivers. Power Converter supplied energy reused energy recycled energy

Lemieux, Guy

427

GAMMA-RAY DETECTION WITH PbO GLASS CONVERTERS IN MWPC: ELECTRON CONVERSION EFFICIENCY AND TIME RESOLUTION  

E-Print Network (OSTI)

Converters in MWPC: Electron Conversion Efficiency and Timeimprove on the electron conversion efficiency and electronconverter the electron conversion efficiency E was measured

Lum, G.K.

2013-01-01T23:59:59.000Z

428

Calculation of HVDC-converter harmonics in frequency domain with regard to asymmetries and comparison with time domain simulations  

SciTech Connect

In order to study the effects of large HVDC converters to the feeding ac networks, it is of importance to explain and to calculate harmonic phenomena which are a result of converter operation. During commissioning of real HVDC converters it could be seen, that harmonics resulting from unsymmetries in the system voltages or from unsymmetries in converter operation led to significant difficulties concerning the system design. For this reason, not only the effects of characteristic but also the effects of noncharacteristic converter harmonics must be taken into account. The aim is to describe the steady state harmonic behavior of the converter. The harmonic spectra are not determined by time domain analysis but instead the solution is found by frequency domain calculations. This can result in reduced calculation time in comparison to conventional fourier analysis of the time functions. The converter is interpreted as an amplitude modulator with voltage and current converter functions which describe the coupling of the dc circuit and the ac network through the converter. To verify the theory, comparison of frequency domain with time domain calculations were carried out.

Rittiger, J. [Siemens AG, Erlangen (Germany); Kulicke, B. [Technische Univ. Berlin (Germany)

1995-10-01T23:59:59.000Z

429

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

E-Print Network (OSTI)

AC Converter for Grid-tied Energy Storage System Xiaolei Hu,resources, grid-tied energy storage systems voltage to abe increasingly incorporated. Energy storage devices allows

King Jet, Tseng

2013-01-01T23:59:59.000Z

430

GAMMA-RAY DETECTION WITH PbO GLASS CONVERTERS IN MWPC: ELECTRON CONVERSION EFFICIENCY AND TIME RESOLUTION  

E-Print Network (OSTI)

1.5 factor. and T and the projection of these results on thethe converter, and the projection of these results on the

Lum, G.K.

2013-01-01T23:59:59.000Z

431

Reducing fischer-tropsch catalyst attrition losses in high ...  

Reducing fischer-tropsch catalyst attrition losses in high agitation reaction systems United States Patent

432

Under U.S.-Russia Partnership, Final Shipment of Fuel Converted From 20,000  

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

Under U.S.-Russia Partnership, Final Shipment of Fuel Converted Under U.S.-Russia Partnership, Final Shipment of Fuel Converted From 20,000 Russian Nuclear Warheads Arrives in United States and Will Be Used for U.S. Electricity Under U.S.-Russia Partnership, Final Shipment of Fuel Converted From 20,000 Russian Nuclear Warheads Arrives in United States and Will Be Used for U.S. Electricity December 10, 2013 - 2:50pm Addthis News Media Contact (202) 586-4940 WASHINGTON, D.C. - The United States and Russia are today commemorating the completion of the 1993 U.S.-Russia HEU Purchase Agreement, commonly known as the Megatons to Megawatts Program, with this week's off-loading of the final shipment of low enriched uranium (LEU) at the Port of Baltimore in Baltimore, Maryland, from Russia. The shipment was the last of the LEU converted from more than 500 metric tons of weapons-origin highly enriched

433

Integration of planar transformer and/or planar inductor with power switches in power converter  

DOE Patents (OSTI)

A power converter integrates at least one planar transformer comprising a multi-layer transformer substrate and/or at least one planar inductor comprising a multi-layer inductor substrate with a number of power semiconductor switches physically and thermally coupled to a heat sink via one or more multi-layer switch substrates.

Chen, Kanghua (Canton, MI); Ahmed, Sayeed (Canton, MI); Zhu, Lizhi (Canton, MI)

2007-10-30T23:59:59.000Z

434

Integrated Power Adapter: Isolated Converter with Integrated Passives and Low Material Stress  

SciTech Connect

ADEPT Project: CPES at Virginia Tech is developing an extremely efficient power converter that could be used in power adapters for small, lightweight laptops and other types of mobile electronic devices. Power adapters convert electrical energy into useable power for an electronic device, and they currently waste a lot of energy when they are plugged into an outlet to power up. CPES at Virginia Tech is integrating high-density capacitors, new magnetic materials, high-frequency integrated circuits, and a constant-flux transformer to create its efficient power converter. The high-density capacitors enable the power adapter to store more energy. The new magnetic materials also increase energy storage, and they can be precisely dispensed using a low-cost ink-jet printer which keeps costs down. The high-frequency integrated circuits can handle more power, and they can handle it more efficiently. And, the constant-flux transformer processes a consistent flow of electrical current, which makes the converter more efficient.

None

2010-09-01T23:59:59.000Z

435

MHK Technologies/Ocean Wave Energy Converter OWEC | Open Energy Information  

Open Energy Info (EERE)

Converter OWEC Converter OWEC < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage Ocean Wave Energy Converter OWEC.jpg Technology Profile Primary Organization Ocean Wave Energy Company Technology Resource Click here Wave Technology Type Click here Point Absorber - Submerged Technology Readiness Level Click here TRL 5 6 System Integration and Technology Laboratory Demonstration Technology Description Neutrally suspended and positively buoyant modules are quick connected into open frame networks Submerged portions are stabilized by variable ballast buoyancy chambers and optional damper sheets situated at a relatively calm depth Frame members carry shaft components of linear rotary converters associated with large point absorber buoys Both directions of reciprocal wave motion i e vertical and horizontal motion directly drive components of counter rotating electrical generators Compared to standard generators wherein one is associated with upstroke and another of smaller proportion with downstroke this configuration increases relative speed with fewer parts Electromechanical loads are real time adjustable with respect to wave sensor web resulting in optimal energy conversion from near fully submerged wave following buoys Electrical conductors are series connected and further quick connected with those of other modules via upper frame members Through implementation of rep

436

Asynchronous Sigma-Delta analog-to digital converter based on the charge pump integrator  

Science Conference Proceedings (OSTI)

The concept of the asynchronous Sigma-Delta analog-to-digital converter (ASD-ADC) based on the charge pump integrator is discussed in the paper. A two-level conversion scheme is utilized. The first level is accomplished by amplitude-to-pulse-width mapping ... Keywords: Asynchronous Sigma-Delta modulation, Asynchronous circuits, Charge pump, Time quantization, Time-to-digital conversion

Dariusz Ko?cielnik; Marek Mi?kowicz

2008-06-01T23:59:59.000Z

437

Steady State Performance Analysis of a VSC-Based HVDC Converter Stations Using PSCAD/EMTDC  

Science Conference Proceedings (OSTI)

This paper presents a steady state performance analysis carried out to study the behavior of a two VSC-based operating as a single-input single output HVDC link. The digital model of the HVDC link has been implemented and evaluated using PSCAD/EMTDC©. ... Keywords: Voltage source converter, HVDC Stations, pulse width modulation, harmonic spectra

Eduardo Vásquez-Mortera; Edgar L. Moreno-Goytia

2008-09-01T23:59:59.000Z

438

Predictive Power Control of Doubly-Fed Induction Generator for Wave Energy Converters  

E-Print Network (OSTI)

the Doubly- fed induction generator (DFIG). This paper deals then with a model-based predictive power control of a DFIG-based Wave Energy Converter (WEC). In the proposed control approach, the predicted output power was calculated using a DFIG linearized state-space model. The DFIG-based WEC power tracking performances further

Paris-Sud XI, Université de

439

Relation between Verifiable Random Functions and Convertible Undeniable Signatures, and New Constructions  

E-Print Network (OSTI)

. Verifiable random functions (VRF) and selectively-convertible undeniable signature (SCUS) schemes were. This directly yields several deterministic SCUS schemes based on existing VRF constructions. In addition, we transaction escrow schemes [14]. 1.2 Our contributions We first show VRF implies deterministic SCUS

440

A novel time-based low-power pipeline analog to digital converter  

Science Conference Proceedings (OSTI)

A new power reduction technique for analog-to-digital converters is proposed in this paper. A novel current-mode algorithm which uses time to perform analog-to-digital conversion has been described and a 12 bit 100-ksample/s time-based pipeline analog ... Keywords: Bottom plate sampling, Continues-time comparator, Digital correction, Pipeline ADC

Mohammad Hossein Zarifi; Javad Frounchi; Shahin Farshchi; Jack W. Judy

2010-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "loss torque converter" 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

A Hybrid Energy System Using Cascaded H-bridge Converter , Zhong Du2  

E-Print Network (OSTI)

energy system, cascaded multilevel converter, single dc source I. INTRODUCTION As different energy generation, storage, and transmission. The power from hybrid energy systems can be combined on the dc side of Energy Source 1 and Energy Source 2. To analyze mode I, a dc source is assumed to be connected

Tolbert, Leon M.

442

A time-based energy-efficient analog-to-digital converter  

E-Print Network (OSTI)

Dual-slope converters use time to perform analog-to-digital conversion but require 2N+1 clock cycles to achieve N bits of precision. We describe a novel algorithm that also uses time to perform analog-to-digital conversion ...

Yang, Heemin Yi, 1976-

2006-01-01T23:59:59.000Z

443

Modeling and controller design of a wind energy conversion system with matrix converter  

Science Conference Proceedings (OSTI)

In order to meet increasing power demand, taking into account economical and environmental factors, wind energy conversion is gradually gaining interest as a suitable source of renewable energy. In this paper, The modeling of the Wind Energy Conversion ... Keywords: FCC, PWM, SPVM, WECS, induction generator, matrix converter CSCF, power control, variable speed, wind turbine

Y. S. Rao; A. J. laxmi; K. M. S. N. Krishna

2011-02-01T23:59:59.000Z

444

Convertibility of Function Points into COSMIC Function Points: A study using Piecewise Linear Regression  

Science Conference Proceedings (OSTI)

Background: COSMIC Function Points and traditional Function Points (i.e., IFPUG Function Points and more recent variation of Function Points, such as NESMA and FISMA) are probably the best known and most widely used Functional Size Measurement methods. ... Keywords: COSMIC Function Points, Data analysis, Function Point analysis, Functional Size Measurement, Functional size measure convertibility, Outliers

Luigi Lavazza; Sandro Morasca

2011-08-01T23:59:59.000Z

445

Stabilizing technique for AC-DC boost PFC converter based on time delay feedback  

Science Conference Proceedings (OSTI)

It is well known that the ac-dc power factor correction (PFC) boost preregulator can present instability at the line frequency. This nonlinear phenomenon can jeopardize the system performances by increasing the total harmonic distortion and decreasing ... Keywords: ac-dc converters, line frequency instability, power factor correction (PFC), time delay feedback (TDF)

Abdelali El Aroudi; Mohamed Orabi

2010-01-01T23:59:59.000Z

446

EPRI HVDC Reference Book: Chapter 13 - DC Transmission with Voltage Sourced Converters  

Science Conference Proceedings (OSTI)

DC Transmission with voltage sourced converters (VSC) is a relatively new development in DC transmission. This report covers circuits, theory and capabilities of this new development in HVDC transmission. The report will be a Chapter in the comprehensive HVDC reference guide that EPRI is preparing.

2009-12-21T23:59:59.000Z

447

Fully monolithic cellular buck converter design for 3-D power delivery  

E-Print Network (OSTI)

A fully monolithic interleaved buck dc-dc point-of-load (PoL) converter has been designed and fabricated in a 0.18-mm SiGe BiCMOS process. Target application of the design is 3-D power delivery for future microprocessors, ...

Sun, Jian

448

System analysis of a negative impedance converter receiver for ultra low frequencies  

Science Conference Proceedings (OSTI)

Monitoring electromagnetic waves in the Ultra Low Frequency (ULF) range between 1 mHz and 1 Hz is essential for an understanding of the processes in the earths magnetosphere. Also earthquake prone areas are under suspect to emit precursor ULF signals. ... Keywords: magnetosphere, negative impedance convert, system analysis, ultra low frequency

Ernst D. Schmitter

2008-07-01T23:59:59.000Z

449

The Effects of Wave Energy Converters on a Monochromatic Wave Climate  

E-Print Network (OSTI)

in wave energy converters as a possible means of providing renewable energy, the effects of a wave energy The interest in renewable energies is currently increasing due to the reported rise in global temperature is that of wave energy. The research is multifaceted and includes research on the efficiency of wave energy

Fox-Kemper, Baylor

450

Generator set, 100kW frequency converter. Final technical report  

SciTech Connect

The Contractor shall furnish all engineering labor, tools, services, supplies, materials, equipment, and facilities necessary to perform an investigation and study of means to extend the capability of the contractor's existing Power Center Inverter System to the 100 kW level. This 100 kW Inverter System shall meet the basic performance parameters of the frequency converter.

Corry, T.

1975-07-01T23:59:59.000Z

451

Cesium-plasma-conductivity enhancement in the advanced thermionic energy converter. Final report  

DOE Green Energy (OSTI)

Two methods of plasma conductivity enhancement in a cesium vapor thermionic energy converter have been studied. The first involved resonance photoabsorption of several cesium lines and the second utilized cesium plasma sustenance by application of microwave power. An extensive study of ionization processes in a cesium discharge in the presence of resonance ionization was made. Calculations were made of expected percentage excitation levels for several cesium resonance transitions for different values of neutral density and temperature as well as incident radiation power levels. The results of some of these computations were tabulated. Several ionization schemes were considered. A number of cesium transitions were investigated in the range of 799 to 870 nanometers for four different cesium reservoir temperatures, 467, 511, 550 and 591 K. The related absorption coefficients of the radiation lines in the plasma were deduced and tabulated. The resulting plasma conductivity increase was recorded and the associated ionization enhancement was deduced. A microwave cavity was built where the emitter and collector of a simple thermionic converter made up two of the cavity walls and resonant microwave power was externally applied. The I-V characteristics of the thermionic converter were studied under several microwave power levels in the range of 0 to 2 watts. Significant shifts to higher currents were observed as the microwave power levels were raised. In conclusion, both methods show promise as auxiliary ionization mechanisms for the thermionic energy converter, especially at low emitter temperatures.

Manikopoulos, C.N.

452

Scannerless loss modulated flash color range imaging  

SciTech Connect

Scannerless loss modulated flash color range imaging methods and apparatus are disclosed for producing three dimensional (3D) images of a target within a scene. Apparatus and methods according to the present invention comprise a light source providing at least three wavelengths (passbands) of illumination that are each loss modulated, phase delayed and simultaneously directed to illuminate the target. Phase delayed light backscattered from the target is spectrally filtered, demodulated and imaged by a planar detector array. Images of the intensity distributions for the selected wavelengths are obtained under modulated and unmodulated (dc) illumination of the target, and the information contained in the images combined to produce a 3D image of the target.

Sandusky, John V. (Albuquerque, NM); Pitts, Todd Alan (Rio Rancho, NM)

2009-02-24T23:59:59.000Z

453

Scannerless loss modulated flash color range imaging  

SciTech Connect

Scannerless loss modulated flash color range imaging methods and apparatus are disclosed for producing three dimensional (3D) images of a target within a scene. Apparatus and methods according to the present invention comprise a light source providing at least three wavelengths (passbands) of illumination that are each loss modulated, phase delayed and simultaneously directed to illuminate the target. Phase delayed light backscattered from the target is spectrally filtered, demodulated and imaged by a planar detector array. Images of the intensity distributions for the selected wavelengths are obtained under modulated and unmodulated (dc) illumination of the target, and the information contained in the images combined to produce a 3D image of the target.

Sandusky, John V. (Albuquerque, NM); Pitts, Todd Alan (Rio Rancho, NM)

2008-09-02T23:59:59.000Z

454

Economics of heat loss for power cables  

SciTech Connect

Energy losses occur in power cables which cause a rise in the conductor temperature. A trend toward higher allowable conductor temperatures has increased the energy losses during operation. At the same time, the costs of the energy has increased dramatically. With a given installation and load, energy costs vary inversely with the conductor size. However, initial costs vary directly with the conductor size. This relationship can be utilized to select a conductor size which minimizes the sum of the initial costs an the energy costs. This paper reviews present value techniques and identifies the level of energy costs in some particular installation configurations. An analysis is made of the marginal costs and savings available by changing the size of the conductor in a cable circuit.

Cornelison, K.E.

1982-07-01T23:59:59.000Z

455

Information Loss in Black Hole Evaporation  

E-Print Network (OSTI)

Parikh-Wilczek tunnelling framework is investigated again. We argue that Parikh-Wilczek's treatment, which satisfies the first law of black hole thermodynamics and consists with an underlying unitary theory, is only suitable for a reversible process. Because of the negative heat capacity, an evaporating black hole is a highly unstable system. That is, the factual emission process is irreversible, the unitary theory will not be satisfied and the information loss is possible.

Jingyi Zhang; Yapeng Hu; Zheng Zhao

2005-12-11T23:59:59.000Z

456

Recent Stirling engine loss - understanding results  

DOE Green Energy (OSTI)

For several years, the National Aeronautics and Space Administration and other US Government agencies have been funding experimental and analytical efforts to improve the understanding of Stirling thermodynamic losses. NASA`s objective is to improve Stirling engine design capability to support the development of new engines for space power. An overview of these efforts was last given at the 1988 IECEC. Recent results of this research are reviewed.

Tew, R.C.; Thieme, L.G.; Dudenhoefer, J.E.

1994-09-01T23:59:59.000Z

457

New one-phase dual converter for superconducting inductive energy storage and transfer applications: the one-phase inductor-converter bridge  

DOE Green Energy (OSTI)

This report presents the results of theoretical and experimental development of the one-phase Inductor-Converter Bridge (ICB). The basic operating principles of the circuit are described followed by a theoretical treatment of the dynamics and control of the system. The successful results of the first experimental operation and control of the one-phase ICB are presented and explained. Finally, a discussion of some of the interesting transient and steady state behavior of the circuit, along with some of its unique features, is given.

Ehsani, M.; Kustom, R.L.

1984-03-01T23:59:59.000Z

458

Thermoelectric converter  

DOE Patents (OSTI)

This invention relates in general to thermoelectric units and more particularly to a tubular thermoelectric unit which includes an array of tandemly arranged radially tapered annular thermoelectric pellets having insulation material of a lower density than the thermoelectric pellets positioned between each pellet. (Official Gazette)

Kim, C.K.

1974-02-26T23:59:59.000Z

459

Sirius A: turbulence or mass loss?  

E-Print Network (OSTI)

Context. Abundance anomalies observed in a fraction of A and B stars of both Pop I and II are apparently related to internal particle transport. Aims. Using available constraints from Sirius A, we wish to determine how well evolutionary models including atomic diffusion can explain observed abundance anomalies when either turbulence or mass loss is used as the main competitor to atomic diffusion. Methods. Complete stellar evolution models, including the effects of atomic diffusion and radiative accelerations, have been computed from the zero age main-sequence of 2.1M\\odot stars for metallicities of Z0 = 0.01 \\pm 0.001 and shown to agree with the observed parameters of Sirius A. Surface abundances were predicted for three values of the mass loss rate and for four values of the mixed surface zone. Results. A mixed mass of ~ 10^-6 M\\odot or a mass loss rate of 10^-13 M\\odot/yr were determined through comparison with observations. Of the 17 abundances determined observationally which are included in our calculati...

Michaud, G; Vick, M

2011-01-01T23:59:59.000Z

460

New power converter topologies for minimizing energy consumption of electronic appliances .  

E-Print Network (OSTI)

??The proliferation of electronic equipment that is permanently connected to the grid causes significant parasitic losses. Yet, the design of power supplies for PCs, servers,… (more)

Nilakantan, Ravishankar

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "loss torque converter" 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

High Efficiency Thermionics (HET-IV) and Converter Advancement (CAP) programs. Final reports  

DOE Green Energy (OSTI)

This report contains the final report of the High Efficiency Thermionics (HET-IV) Program, Attachment A, performed at Rasor Associates, Inc. (RAI); and the final report of the Converter Advancement Program (CAP), performed at the Bettis Atomic Power Laboratory, Attachment B. The phenomenology of cesium-oxygen thermionic converters was elucidated in these programs, and the factors that had prevented the achievement of stable, enhanced cesium-oxygen converter performance for the previous thirty years were identified. Based on these discoveries, cesium-oxygen vapor sources were developed that achieved stable performance with factor-of-two improvements in power density and thermal efficiency, relative to conventional, cesium-only ignited mode thermionic converters. Key achievements of the HET-IV/CAP programs are as follows: a new technique for measuring minute traces of oxygen in cesium atmospheres; the determination of the proper range of oxygen partial pressures for optimum converter performance--10{sup {minus}7} to 10{sup {minus}9} torr; the discovery, and analysis of the cesium-oxygen liquid migration and compositional segregation phenomena; the successful use of capillary forces to contain the migration phenomenon; the use of differential heating to control compositional segregation, and induce vapor circulation; the development of mechanically and chemically stable, porous reservoir structures; the development of precise, in situ oxygen charging methods; stable improvements in emitter performance, up to effective emitter bare work functions of 5.4 eV; stable improvements in barrier index, to value below 1.8 Volts; the development of detailed microscopic models for cesium-oxygen reservoir dynamics and collector work function behavior; and the discovery of new relationships between electrode geometry and Schock Instability.

Geller, C.B.; Murray, C.S.; Riley, D.R. [Bettis Atomic Power Lab., West Mifflin, PA (United States)] [Bettis Atomic Power Lab., West Mifflin, PA (United States); Desplat, J.L.; Hansen, L.K.; Hatch, G.L.; McVey, J.B.; Rasor, N.S. [Rasor Associates, Inc., Sunnyvale, CA (United States)] [Rasor Associates, Inc., Sunnyvale, CA (United States)

1996-04-01T23:59:59.000Z

462

Neutronic design of a fission converter-based epithermal neutron beam for neutron capture therapy  

SciTech Connect

To meet the needs for neutron capture theory (NCT) irradiations, a high-intensity, high-quality fusion converter-based epithermal neutron beam has been designed for the MITR-II research reactor. This epithermal neutron beam, capable of delivering treatments in a few minutes with negligible background contamination from fast neutrons and photons, will be installed in the present thermal column and hohlraum of the 5-MW MITR-II research reactor. Spent or fresh MITR-II fuel elements will be used to fuel the converter. With a fission converter power of {approximately}80 kW using spent fuel, epithermal fluxes (1 eV < E < 10 keV) in excess of 10{sup 10} n/cm{sup 2} {center_dot} s are achievable at the target position with negligible photon and fast neutron contamination, i.e., <2 {times} 10{sup {minus}11}cGy-cm{sup 2}/n. With the currently available {sup 10}B delivery compound boronophenylalanine-fructose, average therapeutic ratios of {approximately}5 can be achieved using this beam for brain irradiations with deep effective penetration ({approximately}9.5 cm) and high dose rates of up to 400 to 600 RBE cGy/min. If NCT becomes an accepted therapy, fission converter-based beams constructed at existing reactors could meet a large fraction of the projected requirements for intense, low-background epithermal neutron beams at a relatively low cost. The results of an extensive set of neutronic design studies investigating all components of the beam are presented. These detailed studies can be useful as guidance for others who may wish to use the fission converter approach to develop epithermal beams for NCT.

Kiger, W.S. III; Sakamoto, S.; Harling, O.K. [Massachusetts Inst. of Tech., Cambridge, MA (United States)

1999-01-01T23:59:59.000Z

463

Performance Evaluation of a Multi-Port DC-DC Current Source Converter for High Power Applications  

E-Print Network (OSTI)

With the ever-growing developments of sustainable energy sources such as fuel cells, photovoltaics, and other distributed generation, the need for a reliable power conversion system that interfaces these sources is in great demand. In order to provide the highest degree of flexibility in a truly distributed network, it is desired to not only interface multiple sources, but to also interface multiple loads. Modern multi-port converters use high frequency transformers to deliver the different power levels, which add to the size and complexity of the system. The different topological variations of the proposed multi-port dc-dc converter have the potential to solve these problems. This thesis proposes a unique dc-dc current source converter for multi-port power conversion. The presented work will explain the proposed multi-port dc-dc converter's operating characteristics, control algorithms, design and a proof of application. The converter will be evaluated to determine its functionality and applicability. Also, it will be shown that our converter has advantages over modern multi-port converters in its ease of scalability from kW to MW, low cost, high power density and adaption to countless combinations of multiple sources. Finally we will present modeling and simulation of the proposed converter using the PSIM software. This research will show that this new converter topology is unstable without feedback control. If the operating point is moved, one of the source ports of the multiport converter becomes unstable and dies off supplying very little or no power to the load while the remaining source port supplies all of the power the load demands. In order to prevent this and add stability to the converter a simple yet unique control method was implemented. This control method allowed for the load power demanded to be shared between the two sources as well as regulate the load voltage about its desired value.

Yancey, Billy Ferrall

2010-05-01T23:59:59.000Z

464

Original article: Adaptive sliding mode control of interleaved parallel boost converter for fuel cell energy generation system  

Science Conference Proceedings (OSTI)

This paper deals with the problem of controlling energy generation systems including fuel cells (FCs) and interleaved boost power converters. The proposed nonlinear adaptive controller is designed using sliding mode control (SMC) technique based on the ... Keywords: Adaptive control, Fuel cell, Interleaved boost converter, Sliding mode control

H. El Fadil, F. Giri, Josep M. Guerrero

2013-05-01T23:59:59.000Z

465

Study on Tubular Busbar Corona Design Optimization of ±660kV HVDC Converter Substation in Qingdao  

Science Conference Proceedings (OSTI)

The HVDC busbar corona characteristic is the main factor taken into account for choosing busbar of HVDC converter substation. By establishing the calculation models of electric field strength along the busbar surface, ground total electric field strength ... Keywords: ±660 kV HVDC, converter substation, corona characteristics, electromagnetic, tubular busbar optimization

Xu Mingming; Li Kejun; Tan Zhenyu; Niu Lin

2010-06-01T23:59:59.000Z

466

Operating space of a bidirectional PWM ac-to-dc converter applied in active line-conditioning  

Science Conference Proceedings (OSTI)

The paper presents the operating space of a bidirectional PWM ac-to-dc converter which can act also as a line conditioner. This analysis of the operating space will prove the secondary line conditioning functionality of the PWM dc converters. Starting ...

R. Paku; R. Marschalko

2008-05-01T23:59:59.000Z

467

Phase-Shifted Full Bridge DC-DC Converter with Energy Recovery Clamp and Reduced Circulating Current  

E-Print Network (OSTI)

Phase-Shifted Full Bridge DC-DC Converter with Energy Recovery Clamp and Reduced Circulating an improved PSFB DC-DC converter using only a modified energy recovery clamp circuit attached at the secondary and/or output voltage changes. Section II describes the PSFB DC-DC circuit with the proposed energy

468

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

E-Print Network (OSTI)

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

Schrock, Kenneth C

2008-01-01T23:59:59.000Z

469

HVDC converter stations for voltages above 600 kV: R and D needs and priorities: Final report  

Science Conference Proceedings (OSTI)

A study of the R and D needed to build converter stations for HVDC transmission lines with pole-to-ground voltages between 800 and 1200 kV confirmed that economical designs for more than 800 kV will require long-term R and D. Converter stations for 800 kV appear possible with existing technology.

Krishnayya, P.C.S.; Maruvada, P.S.; Lambeth, P.J.; Desilets, G.; Trinh, N.G.

1986-12-01T23:59:59.000Z

470

Boost Converters for Gas Electric and Fuel Cell Hybrid Electric Vehicles  

DOE Green Energy (OSTI)

Hybrid electric vehicles (HEVs) are driven by at least two prime energy sources, such as an internal combustion engine (ICE) and propulsion battery. For a series HEV configuration, the ICE drives only a generator, which maintains the state-of-charge (SOC) of propulsion and accessory batteries and drives the electric traction motor. For a parallel HEV configuration, the ICE is mechanically connected to directly drive the wheels as well as the generator, which likewise maintains the SOC of propulsion and accessory batteries and drives the electric traction motor. Today the prime energy source is an ICE; tomorrow it will very likely be a fuel cell (FC). Use of the FC eliminates a direct drive capability accentuating the importance of the battery charge and discharge systems. In both systems, the electric traction motor may use the voltage directly from the batteries or from a boost converter that raises the voltage. If low battery voltage is used directly, some special control circuitry, such as dual mode inverter control (DMIC) which adds a small cost, is necessary to drive the electric motor above base speed. If high voltage is chosen for more efficient motor operation or for high speed operation, the propulsion battery voltage must be raised, which would require some type of two-quadrant bidirectional chopper with an additional cost. Two common direct current (dc)-to-dc converters are: (1) the transformer-based boost or buck converter, which inverts a dc voltage, feeds the resulting alternating current (ac) into a transformer to raise or lower the voltage, and rectifies it to complete the conversion; and (2) the inductor-based switch mode boost or buck converter [1]. The switch-mode boost and buck features are discussed in this report as they operate in a bi-directional chopper. A benefit of the transformer-based boost converter is that it isolates the high voltage from the low voltage. Usually the transformer is large, further increasing the cost. A useful feature of the switch mode boost converter is its simplicity. Its inductor must handle the entire current, which is responsible for its main cost. The new Z-source inverter technology [2,3] boosts voltage directly by actively using the zero state time to boost the voltage. In the traditional pulse width modulated (PWM) inverter, this time is used only to control the average voltage by disconnecting the supply voltage from the motor. The purpose of this study is to examine the Z-source's potential for reducing the cost and improving the reliability of HEVs.

McKeever, JW

2005-06-16T23:59:59.000Z

471

Boost Converters for Gas Electric and Fuel Cell Hybrid Electric Vehicles  

SciTech Connect

Hybrid electric vehicles (HEVs) are driven by at least two prime energy sources, such as an internal combustion engine (ICE) and propulsion battery. For a series HEV configuration, the ICE drives only a generator, which maintains the state-of-charge (SOC) of propulsion and accessory batteries and drives the electric traction motor. For a parallel HEV configuration, the ICE is mechanically connected to directly drive the wheels as well as the generator, which likewise maintains the SOC of propulsion and accessory batteries and drives the electric traction motor. Today the prime energy source is an ICE; tomorrow it will very likely be a fuel cell (FC). Use of the FC eliminates a direct drive capability accentuating the importance of the battery charge and discharge systems. In both systems, the electric traction motor may use the voltage directly from the batteries or from a boost converter that raises the voltage. If low battery voltage is used directly, some special control circuitry, such as dual mode inverter control (DMIC) which adds a small cost, is necessary to drive the electric motor above base speed. If high voltage is chosen for more efficient motor operation or for high speed operation, the propulsion battery voltage must be raised, which would require some type of two-quadrant bidirectional chopper with an additional cost. Two common direct current (dc)-to-dc converters are: (1) the transformer-based boost or buck converter, which inverts a dc voltage, feeds the resulting alternating current (ac) into a transformer to raise or lower the voltage, and rectifies it to complete the conversion; and (2) the inductor-based switch mode boost or buck converter [1]. The switch-mode boost and buck features are discussed in this report as they operate in a bi-directional chopper. A benefit of the transformer-based boost converter is that it isolates the high voltage from the low voltage. Usually the transformer is large, further increasing the cost. A useful feature of the switch mode boost converter is its simplicity. Its inductor must handle the entire current, which is responsible for its main cost. The new Z-source inverter technology [2,3] boosts voltage directly by actively using the zero state time to boost the voltage. In the traditional pulse width modulated (PWM) inverter, this time is used only to control the average voltage by disconnecting the supply voltage from the motor. The purpose of this study is to examine the Z-source's potential for reducing the cost and improving the reliability of HEVs.

McKeever, JW

2005-06-16T23:59:59.000Z

472

System Losses and Assessment Trade Study  

SciTech Connect

This Advanced Fuel Cycle Initiative (AFCI) study has developed new analysis methods to examine old and new technology options toward the goal of improving fuel cycle systems. We have integrated participants and information from AFCI Systems Analysis, Transmutation Fuels, Separations, and Waste Form Campaigns in the Systems Losses and Assessment Trade Study. The initial objectives of this study were to 1) increase understanding of system interdependencies and thereby identify system trade-offs that may yield important insights, 2) define impacts of separations product purity on fuel manufacture and transmutation reactivity, 3) define impacts from transuranic (TRU) losses to waste, 4) identify the interrelationships involved in fuels and separations technology performance, and 5) identify system configuration adjustments with the greatest potential for influencing system losses. While bounding and analyzing this initial problem, we also identified significantly higher-level programmatic drivers with broad implications to the current fuel cycle research charter and the general issue of a DOE complex wide need for a comprehensive and integrated nuclear material management as addressed by the new DOE Order 410.2 titled “Management of Nuclear Materials”. The initial modeling effort developed in this study for a much smaller subset of material (i.e., commercial fuel) and a selected transmutation scheme (i.e., fast reactor recycling) is a necessary first step towards examining a broader set of nuclear material management options, dispositioning strategies and integrated waste management options including potential areas of research leverage. The primary outcome from this initial study has been an enhanced integration among Campaigns and associated insights and analysis methods. Opportunities for improved understanding between the groups abound. The above lanthanide-actinide example highlights the importance of evaluating options via integration across the Campaigns. Plans for Fiscal Year 2010 are being made in a coordinated fashion such that the knowledge gained from the research performed by the Campaigns can benefit on-going work of the study, and that improved understanding of the system relationships can be used to guide the specific research and development (R&D) activities within the Campaigns. In FY-10, the System Losses and Assessment Trade Study will carry-over activities from FY-09. We will continue to refine impurity and loss estimates and impurity limits on fuels by incorporating results from ongoing R&D. And we will begin work on an enhanced nuclear material management model to allow us to continue to improve our overall system understanding of the trade-offs between separations, fuel fabrication, waste forms, waste disposition, SNM losses, reactor performance, and proliferation resistance. In the future, we can also better understand how used fuel and other forms of remote-handled SNM can be better integrated into an overall nuclear material management program that will evolve for the DOE complex via Order 410.2 (DOE 2009).

David Shropshire; Steve Piet; Nick Soelberg; Robert Cherry; Roger Henry; David Meikrantz; Greg Teske; Eric Shaber; Candido Pereira

2009-09-01T23:59:59.000Z

473

Optimal detection of losses by thermal probes  

E-Print Network (OSTI)

We consider the discrimination of lossy bosonic channels and focus to the case when one of the values for the loss parameter is zero, i.e., we address the detection of a possible loss against the alternative hypothesis of an ideal lossless channel. This discrimination is performed by inputting one-mode or two-mode squeezed thermal states with fixed total energy. By optimizing over this class of states, we find that the optimal inputs are pure, thus corresponding to single- and two-mode squeezed vacuum states. In particular, we show that for any value of the damping rate smaller than a critical value there is a threshold on the energy that makes the two-mode squeezed vacuum state more convenient than the corresponding single-mode state, whereas for damping larger than this critical value two-mode squeezed vacua are always better. We then consider the discrimination in realistic conditions, where it is unlikely to have pure squeezing. Thus by fixing both input energy and squeezing, we show that two-mode squeezed thermal states are always better than their single- mode counterpart when all the thermal photons are directed into the dissipative channel. Besides, this result also holds approximately for unbalanced distribution of the thermal photons. Finally, we also investigate the role of correlations in the improvement of detection. For fixed input squeezing (single-mode or two-mode), we find that the reduction of the quantum Chernoff bound is a monotone function of the two-mode entanglement as well as the quantum mutual information and the quantum discord. We thus verify that employing squeezing in the form of correlations (quantum or classical) is always a resource for loss detection whenever squeezed thermal states are taken as input.

Carmen Invernizzi; Matteo G. A. Paris; Stefano Pirandola

2010-11-11T23:59:59.000Z

474

Optimization of DC-DC Converters for Improved Electromagnetic Compatibility With High Energy Physics Front-End Electronics  

E-Print Network (OSTI)

The upgrade of the Large Hadron Collider (LHC) experiments at CERN sets new challenges for the powering of the detectors. One of the powering schemes under study is based on DC-DC buck converters mounted on the front-end modules. The hard environmental conditions impose strict restrictions to the converters in terms of low volume, radiation and magnetic field tolerance. Furthermore, the noise emission of the switching converters must not affect the performance of the powered systems. A study of the sources and paths of noise of a synchronous buck converter has been made for identifying the critical parameters to reduce their emissions. As proof of principle, a converter was designed following the PCB layout considerations proposed and then used for powering a silicon strip module prototype for the ATLAS upgrade, in order to evaluate their compatibility.

Fuentes, C; Michelis, S; Blanchot, G; Allongue, B; Faccio, F; Orlandi, S; Kayal, M; Pontt, J

2011-01-01T23:59:59.000Z

475

Electrical performance characteristics of high power converters for space power applications. Final report, 1 January 1988-30 September 1989  

SciTech Connect

The first goal of this project was to investigate various converters that would be suitable for processing electric power derived from a nuclear reactor. The implementation is indicated of a 20 kHz system that includes a source converter, a ballast converter, and a fixed frequency converter for generating the 20 kHz output. This system can be converted to dc simply by removing the fixed frequency converter. This present study emphasized the design and testing of the source and ballast converters. A push-pull current-fed (PPCF) design was selected for the source converter, and a 2.7 kW version of this was implemented using three 900 watt modules in parallel. The characteristic equation for two converters in parallel was derived, but this analysis did not yield any experimental methods for measuring relative stability. The three source modules were first tested individually and then in parallel as a 2.7 kW system. All tests proved to be satisfactory; the system was stable; efficiency and regulation were acceptable; and the system was fault tolerant. The design of a ballast-load converter, which was operated as a shunt regulator, was investigated. The proposed power circuit is suitable for use with BJTs because proportional base drive is easily implemented. A control circuit which minimizes switching frequency ripple and automatically bypasses a faulty shunt section was developed. A nonlinear state-space-averaged model of the shunt regulator was developed and shown to produce an accurate incremental (small-signal) dynamic model, even though the usual state-space-averaging assumptions were not met. The nonlinear model was also shown to be useful for large-signal dynamic simulation using PSpice.

Stuart, T.A.; King, R.J.

1989-09-01T23:59:59.000Z