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Note: This page contains sample records for the topic "variable speed permanent" 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

Controlled operation of variable speed driven permanent magnet synchronous generator for wind energy conversion systems  

Science Conference Proceedings (OSTI)

The introduction of distributed generation through renewable sources of energy has opened a challenging area for power engineers. As these sources are intermittent in nature, variable speed electric generators are employed for harnessing electrical energy ... Keywords: permanent magnet synchronous generator, power conditioners, power quality, variable speed generators, wind energy

Rajveer Mittal; K. S. Sandhu; D. K. Jain

2009-02-01T23:59:59.000Z

2

SUPER HIGH-SPEED MINIATURIZED PERMANENT MAGNET SYNCHRONOUS MOTOR  

E-Print Network (OSTI)

SUPER HIGH-SPEED MINIATURIZED PERMANENT MAGNET SYNCHRONOUS MOTOR by LIPING ZHENG B.S. Shanghai with the design of permanent magnet synchronous motors (PMSM) to operate at super-high speed with high efficiency the motor to have an efficiency reaching above 92%. This achieved efficiency indicated a significant

Wu, Shin-Tson

3

Sensorless Speed Control of Permanent Magnet-Assisted Synchronous Reluctance Motor (PMa-SynRM)  

E-Print Network (OSTI)

An interesting alternative for today's high efficiency variable speed drives is the Permanent Magnet-Assisted Synchronous Reluctance Motor drive, which belongs to the family of brushless synchronous AC motor drives. Generally, the reluctance torque of this motor is significant compared to the Permanent Magnet electrical torque. The advantage of increased reluctance torque is the decreased need of expensive permanent magnet (PM) material, which makes this solution thus cheaper than the respective permanent magnet motor. Also due to its synchronous operation, sensorless rotational control is possible along with higher power factor and better efficiency compared to the induction motor (IM). Therefore, this thesis first deals with the implementation of a vector control strategy for speed control of the PMa-synRM motor that can be applied to a washing machine application. The machine is supplied by a current controlled voltage source PWM inverter to control the instantaneous stator currents which are decided by the reference speed. Secondly, the thesis focuses on the sensorless speed operation of the PMa-SynRM to take advantage of the lower costs as well as increased system reliability which otherwise is not possible using the delicate speed or position sensors. The concept involves estimation of the rotor speed and/or position. There are several speed estimation techniques proposed by researchers and among them the observer based technique is proven and commonly used in the industry. The only requirements of the observer system are a very fast signal processor, specialized and optimized to perform complex mathematical calculations. The feasibility and effectiveness of the control techniques are verified using the experimental results, implemented using the Texas Instruments TMS320F2812 eZDSP controller board and the overall motor drive system in the laboratory.

Chakali, Anil K.

2009-12-01T23:59:59.000Z

4

Energy Savings of Variable Speed Motors  

E-Print Network (OSTI)

This paper investigates the energy savings available by utilizing variable speed motors on pump and fan applications. Conventional control of flow or pressure in process plants is normally accomplished by throttling the various streams with control valves. Depending on the system and the actual operating conditions, this throttling may consume a considerable amount of energy. The hydraulics of different systems are investigated to generalize high energy saving applications. Typical pump characteristics at varying speeds are investigated since most performance curves are only available at a constant speed. The various types of variable speed electric motors are discussed. However, the primary variable speed system recommended is a variable frequency speed system which utilizes standard induction motors. Specific cases of centrifugal pump applications and cooling tower fan service are presented. Turndown frequencies, stream factors, and electric rates are included in the evaluation. The energy savings of a variable speed system becomes significant when flow rates vary widely and the electrical rates are high.

Fishel, F. D.

1979-01-01T23:59:59.000Z

5

Modelling and simulation of an autonomous variable speed micro hydropower station  

Science Conference Proceedings (OSTI)

In this paper, the modelling of an autonomous variable speed micro hydropower station is presented. It is composed of a doubly fed induction generator linked mechanically and electrically to a permanent magnet synchronous machine which may recover or ... Keywords: Distributed generation, Doubly fed induction machine, Micro hydroelectricity, Variable speed autonomous hydrogenerator

A. Ansel; B. Robyns

2006-06-01T23:59:59.000Z

6

Modelling and simulation of an autonomous variable speed micro hydropower station  

Science Conference Proceedings (OSTI)

In this paper, the modelling of an autonomous variable speed micro hydropower station is presented. It is composed of a doubly fed induction generator linked mechanically and electrically to a permanent magnet synchronous machine which may recover or ... Keywords: distributed generation, doubly fed induction machine, micro hydroelectricity, variable speed autonomous hydrogenerator

A. Ansel; B. Robyns

2006-06-01T23:59:59.000Z

7

Design of optimal digital controller for stable super-high-speed permanent-magnet synchronous  

E-Print Network (OSTI)

Design of optimal digital controller for stable super-high-speed permanent-magnet synchronous motor collaborative design scheme of a super-high-speed permanent-magnet synchronous motor (PMSM) and its digital controller is presented, which provides a low-cost but highly efficient motor system with guaranteed

Wu, Shin-Tson

8

296 IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS, VOL. 57, NO. 1, JANUARY 2010 Very-High-Speed Slotless Permanent-Magnet  

E-Print Network (OSTI)

-High-Speed Slotless Permanent-Magnet Motors: Analytical Modeling, Optimization, Design, and Torque Measurement Methods-high-speed (VHS) slotless permanent-magnet motor design procedure using an analytical model. The model is used TO THEIR high power density, very-high-speed (VHS) permanent-magnet (PM) motors are increasingly requested

Psaltis, Demetri

9

IEEE TRANSACTIONS ON MAGNETICS, VOL. 41, NO. 10, OCTOBER 2005 3823 Design of a Superhigh-Speed Cryogenic Permanent  

E-Print Network (OSTI)

-Speed Cryogenic Permanent Magnet Synchronous Motor Liping Zheng1, Thomas X. Wu1, Dipjyoti Acharya2, Kalpathy B and simulation of a superhigh-speed permanent magnet synchronous motor (PMSM) that operates in the cryogenic Terms--Cryogenics, permanent magnet synchronous motor (PMSM), superhigh speed, V/f control. I

Wu, Shin-Tson

10

Thermodynamics in variable speed of light theories  

SciTech Connect

The perfect fluid in the context of a covariant variable speed of light theory proposed by J. Magueijo is studied. On the one hand the modified first law of thermodynamics together with a recipe to obtain equations of state are obtained. On the other hand the Newtonian limit is performed to obtain the nonrelativistic hydrostatic equilibrium equation for the theory. The results obtained are used to determine the time variation of the radius of Mercury induced by the variability of the speed of light (c), and the scalar contribution to the luminosity of white dwarfs. Using a bound for the change of that radius and combining it with an upper limit for the variation of the fine structure constant, a bound on the time variation of c is set. An independent bound is obtained from luminosity estimates for Stein 2015B.

Racker, Juan [CONICET, Centro Atomico Bariloche, Avenida Bustillo 9500 (8400), San Carlos De Bariloche (Argentina); Facultad de Ciencias Astronomicas y Geofisicas, Universidad Nacional de La Plata, Paseo del Bosque S/N (1900), La Plata (Argentina); Sisterna, Pablo [Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, Funes 3350 (7600), Mar del Plata (Argentina); Vucetich, Hector [Facultad de Ciencias Astronomicas y Geofisicas, Universidad Nacional de La Plata, Paseo del Bosque S/N (1900), La Plata (Argentina)

2009-10-15T23:59:59.000Z

11

Thermodynamics in variable speed of light theories  

E-Print Network (OSTI)

The perfect fluid in the context of a covariant variable speed of light theory proposed by J. Magueijo is studied. On the one hand the modified first law of thermodynamics together with a recipe to obtain equations of state are obtained. On the other hand the Newtonian limit is performed to obtain the nonrelativistic hydrostatic equilibrium equation for the theory. The results obtained are used to determine the time variation of the radius of Mercury induced by the variability of the speed of light ($c$), and the scalar contribution to the luminosity of white dwarfs. Using a bound for the change of that radius and combining it with an upper limit for the variation of the fine structure constant, a bound on the time variation of $c$ is set. An independent bound is obtained from luminosity estimates for Stein 2015B.

Juan Racker; Pablo Sisterna; Hector Vucetich

2007-11-06T23:59:59.000Z

12

Flight Control Design for Rotorcraft with Variable Rotor Speed.  

E-Print Network (OSTI)

??Flight control design issues for rotorcraft with variable rotor speed are investigated, and new design methodologies are developed to deal with the challenges of variable… (more)

Guo, Wei

2009-01-01T23:59:59.000Z

13

Variable-speed blower motors gaining ground in residential HVAC market  

SciTech Connect

Variable-speed blowers with electronically commutated permanent-magnet motors are gaining ground in the residential forced-air HVAC market. Variable-speed blower motors offer better comfort, better air mixing, lower noise, and tighter temperature and humidity control, as well as higher efficiency and lower peak demand than the constant-speed blower motors installed in most standard systems. Although these benefits cost considerably more up front, some homeowners think the extra cost is justified. Sales are increasing dramatically, and although variable-speed units made up less than three percent of the market in 1993, industry representatives predict that variable-speed blower motors may become the standard within ten to twenty years. The benefits of variable-speed gas furnaces also open up the potential for collaboration between gas and electric utilities. The best way for an electric utility to encourage customers to consider variable-speed gas furnaces may be through the gas utility, since homeowners look to the gas utility when it`s time to make a decision about a gas furnace purchase. Gas utilities can also benefit from variable speed by providing their customers better comfort, and possibly by reducing the customer`s gas bill (due to zoning or better control).

Gregerson, J.

1994-12-31T23:59:59.000Z

14

Sliding mode control law for a variable speed wind turbine  

Science Conference Proceedings (OSTI)

Modern wind turbines are designed in order to work in variable speed operations. To perform this task, wind turbines are provided with adjustable speed generators, like the double feed induction generator. One of the main advantage of adjustable speed ... Keywords: modeling and simulation, variable structure control, wind turbine control

Oscar Barambones; Jose Maria Gonzalez De Durana; Patxi Alkorta; Jose Antonio Ramos; Manuel De La Sen

2011-02-01T23:59:59.000Z

15

Building Technologies Office: Advanced, Variable Speed Air-Source  

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

Advanced, Variable Advanced, Variable Speed Air-Source Integrated Heat Pumps Research Project to someone by E-mail Share Building Technologies Office: Advanced, Variable Speed Air-Source Integrated Heat Pumps Research Project on Facebook Tweet about Building Technologies Office: Advanced, Variable Speed Air-Source Integrated Heat Pumps Research Project on Twitter Bookmark Building Technologies Office: Advanced, Variable Speed Air-Source Integrated Heat Pumps Research Project on Google Bookmark Building Technologies Office: Advanced, Variable Speed Air-Source Integrated Heat Pumps Research Project on Delicious Rank Building Technologies Office: Advanced, Variable Speed Air-Source Integrated Heat Pumps Research Project on Digg Find More places to share Building Technologies Office: Advanced,

16

Some preliminary results from the NWTC direct-drive, variable-speed test bed  

SciTech Connect

With the remarkable rise in interest in variable-speed operation of larger wind turbines, it has become important for the National Wind Technology Center (NWTC) to have access to a variable-speed test bed that can be specially instrumented for research. Accordingly, a three-bladed, 10-meter, downwind, Grumman Windstream machine has been equipped with a set of composite blades and a direct-coupled, permanent-magnet, 20 kilowatt generator. This machine and its associated control system and data collection system are discussed. Several variations of a maximum power control algorithm have been installed on the control computer. To provide a baseline for comparison, several constant speed algorithms have also been installed. The present major effort is devoted to daytime, semi-autonomous data collection.

Carlin, P.W.; Fingersh, L.J.

1996-10-01T23:59:59.000Z

17

Variable-Speed Wind System Design : Final Report.  

SciTech Connect

Almost from the onset of the development of wind energy conversion systems (WECS), it was known that variable-speed operation of the turbine would maximize energy capture. This study was commissioned to assess the cost, efficiency gain, reduction of the cost of energy (COE), and other operating implications of converting the existing hardware of a modern fixed-speed wind energy conversion system to variable-speed operation. The purpose of this study was to develop a preliminary design for the hardware required to allow variable-speed operation using a doubly-fed generator with an existing fixed-speed wind turbine design. The turbine selected for this study is the AWT-26 designed and built by Advanced Wind Turbines Inc. of Redmond, Washington. The lowest projected COE using this variable-speed generation system is projected to be $0.0499/kWh, compared to the lowest possible COE with fixed-speed generation which is projected to be $0.0546/kWh. This translates into a 8.6% reduction of the COE using this variable-speed generation option. The preliminary system design has advanced to where the printed circuit boards can be physically laid out based on the schematics and the system software can be written based on the control flow-charts. The core of hardware and software has been proven to be successful in earlier versions of VSG systems. The body of this report presents the results of the VSWG system development. Operation under normal and fault conditions is described in detail, the system performance for variable-speed operation is estimated and compared to the original fixed-speed system performance, and specifications for all system components (generator, power electronic converter, and system controller) are given. Costs for all components are estimated, and incremental system cost is compared to incremental energy production. Finally, operational features of the VSWG which are not available in the existing FSWG system are outlined.

Lauw, Hinan K.; Weigand, Claus H.; Marckx, Dallas A.; Electronic Power Conditioning, Inc.

1993-10-01T23:59:59.000Z

18

Trends and Interannual Variability of Wind Speed Distributions in Minnesota  

Science Conference Proceedings (OSTI)

Near-surface wind speed variability is investigated at seven stations in and surrounding Minnesota for recent climate records of 22–35 yr in length. Analyses focus on mean annual wind speeds and on the 10th, 25th, 50th, 75th, and 90th percentiles ...

Katherine Klink

2002-11-01T23:59:59.000Z

19

LQG Controller for a Variable Speed Pitch Regulated Wind Turbine  

Science Conference Proceedings (OSTI)

This paper deals with the design of LQG controllers for pitch regulated, variable speed wind turbines where the controller is used primarily for controlling the pitch angle through a collective pitch angle in the high wind speed in order to guarantee ... Keywords: LQG controller, Pitch control, Wind Trubine

Xingjia Yao; Shu Liu; Guangkun Shan; Zuoxia Xing; Changchun Guo; Chuanbao Yi

2009-08-01T23:59:59.000Z

20

Sliding mode control strategy for variable speed wind turbine  

Science Conference Proceedings (OSTI)

The efficiency of the wind power conversions systems can be greatly improved using an appropriate control algorithm. In this work, a robust control for variable speed wind power generation that incorporates a doubly feed induction generator is described. ...

Oscar Barambones; Jose Maria Gonzalez De Durana

2009-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "variable speed permanent" 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

Variable Speed Fan Retrofits for Computer Room Air Conditioners  

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

Variable-Speed Fan Retrofits for Computer-Room Air Conditioners Prepared for the U.S. Department of Energy Federal Energy Management Program Technology Case Study Bulletin By...

22

Advanced Variable Speed Air-Source Integrated Heat Pump  

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

variable speed air-source variable speed air-source integrated heat pump (AS-IHP) - CRADA Van D. Baxter Oak Ridge National Laboratory vdb@ornl.gov; 865-574-2104 April 3, 2013 Development of advanced HVAC/WH system options for efficient residential or small commercial buildings, new const. or retrofit * ET R&D project in support of DOE/BTO Goal of 50% Reduction in Building Energy Use by 2030 IHP concept - all HVAC & WH services integrated into

23

Advanced Variable Speed Air-Source Integrated Heat Pump  

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

variable speed air-source variable speed air-source integrated heat pump (AS-IHP) - CRADA Van D. Baxter Oak Ridge National Laboratory vdb@ornl.gov; 865-574-2104 April 3, 2013 Development of advanced HVAC/WH system options for efficient residential or small commercial buildings, new const. or retrofit * ET R&D project in support of DOE/BTO Goal of 50% Reduction in Building Energy Use by 2030 IHP concept - all HVAC & WH services integrated into

24

Measure Guideline: Replacing Single-Speed Pool Pumps with Variable Speed Pumps for Energy Savings  

Science Conference Proceedings (OSTI)

The report evaluates potential energy savings by replacing traditional single-speed pool pumps with variable speed pool pumps, and provide a basic cost comparison between continued uses of traditional pumps verses new pumps. A simple step-by-step process for inspecting the pool area and installing a new pool pump follows.

Hunt, A.; Easley, S.

2012-05-01T23:59:59.000Z

25

Results from the NREL Variable-Speed Test bed  

DOE Green Energy (OSTI)

The NREL Variable-Speed Test bed turbine has been used to examine the performance and controllability of a variable-speed, variable-pitch turbine. Control strategies that eliminate drive-train torque fluctuations in high winds have been published before and example data are given here. The energy capture of a variable-speed wind turbine depends in part on its ability to successfully operate at the peak of the C{sub p}-{lambda} curve. The losses associated with the inability of the rotor to stay exactly on top of the curve at all have been found and quantified. New control strategies for improving energy capture in moderate winds are also proposed. The potential exists to improve overall energy capture by 5% or more.

Fingersh, L.J.; Carlin, P.W. [National Renewable Energy Lab., Golden, CO (United States). National Wind Technology Center

1997-11-01T23:59:59.000Z

26

Variable current speed controller for eddy current motors  

DOE Patents (OSTI)

A speed control system for eddy current motors is provided in which the current to the motor from a constant frequency power source is varied by comparing the actual motor speed signal with a setpoint speed signal to control the motor speed according to the selected setpoint speed. A three-phase variable voltage autotransformer is provided for controlling the voltage from a three-phase power supply. A corresponding plurality of current control resistors is provided in series with each phase of the autotransformer output connected to inputs of a three-phase motor. Each resistor is connected in parallel with a set of normally closed contacts of plurality of relays which are operated by control logic. A logic circuit compares the selected speed with the actual motor speed obtained from a digital tachometer monitoring the motor spindle speed and operated the relays to add or substract resistance equally in each phase of the motor input to vary the motor current to control the motor at the selected speed.

Gerth, H.L.; Bailey, J.M.; Casstevens, J.M.; Dixon, J.H.; Griffith, B.O.; Igou, R.E.

1982-03-12T23:59:59.000Z

27

Variable speed operation of generators with rotor-speed feedback in wind power applications  

SciTech Connect

The use of induction generators in wind power applications has been common since the early development of the wind industry. Most of these generators operate at fixed frequency and are connected directly to the utility grid. Unfortunately, this mode of operation limits the rotor speed to a specific rpm. Variable-speed operation is preferred in order to facilitate maximum energy capture over a wide range of wind speeds. This paper explores variable-speed operating strategies for wind turbine applications. The objectives are to maximize energy production, provide controlled start-up and reduce torque loading. This paper focuses on optimizing the energy captured by operating at maximum aerodynamic efficiency at any wind speed. The control strategy we analyze uses rotor speed and generator power as the feedback signals. In the normal operating region, rotor speed is used to compute a target power that corresponds to optimum operation. With power as the control objective, the power converter and generator are controlled to track the target power at any rpm. Thus, the torque-speed characteristic of the generator is shaped to optimize the energy capture. The target power is continuously updated at any rpm. in extreme areas of the operating envelope, during start-up, shutdown, generator overload, or overspeed, different strategies driven by other system considerations must be used.

Muljadi, E.; Butterfield, C.P.; Migliore, P.

1995-11-01T23:59:59.000Z

28

Analysis of a teetered, variable-speed rotor: final report  

DOE Green Energy (OSTI)

A computer model of a horizontal axis wind turbine (HOOT) with four structural degrees of freedom has been derived and verified. The four degrees of freedom include flapwise motion of the blades, teeter motion, and variable rotor speed. Options for the variable rotor speed include synchronous, induction, and constant-tip speed generator models with either start, stop, or normal operations. Verification is made by comparison with analytical solutions and mean and cyclic ESI-80 data. The Veers full-field turbulence model is used as a wind input for a synchronous and induction generator test case during normal operation. As a result of the comparison, it is concluded that the computer model can be used to predict accurately mean and cyclic loads with a turbulent wind input. 47 refs., 19 figs.

Weber, T.L.; Wilson, R.E.; Walker, S.N. (Oregon State Univ., Corvallis, OR (USA). Dept. of Mechanical Engineering) [Oregon State Univ., Corvallis, OR (USA). Dept. of Mechanical Engineering

1991-06-01T23:59:59.000Z

29

Design Procedure for a Very High Speed Slotless Permanent Magnet Motor Pierre-Daniel Pfister, Student Member, IEEE and Yves Perriard, Senior Member, IEEE  

E-Print Network (OSTI)

Design Procedure for a Very High Speed Slotless Permanent Magnet Motor Pierre-Daniel Pfister speed slotless permanent magnet motor design procedure using an analyti- cal model. The multiphysics magnet (PM) motors are increasingly demanded on the market [1]. In a VHS motor, the different parts

Psaltis, Demetri

30

Systematic Controller Design Methodology for Variable-Speed Wind Turbines  

DOE Green Energy (OSTI)

Variable-speed, horizontal axis wind turbines use blade-pitch control to meet specified objectives for three operational regions. This paper provides a guide for controller design for the constant power production regime. A simple, rigid, non-linear turbine model was used to systematically perform trade-off studies between two performance metrics. Minimization of both the deviation of the rotor speed from the desired speed and the motion of the actuator is desired. The robust nature of the proportional-integral-derivative controller is illustrated, and optimal operating conditions are determined. Because numerous simulation runs may be completed in a short time, the relationship between the two opposing metrics is easily visualized.

Hand, M. M.; Balas, M. J.

2002-02-01T23:59:59.000Z

31

Variable Speed Fan Retrofits for Computer Room Air Conditioners  

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

Variable-Speed Fan Variable-Speed Fan Retrofits for Computer-Room Air Conditioners Prepared for the U.S. Department of Energy Federal Energy Management Program Technology Case Study Bulletin By Lawrence Berkeley National Laboratory Steve Greenberg September 2013 2 Contacts Steve Greenberg Lawrence Berkeley National Laboratory One Cyclotron Road, 90R3111 Berkeley, California 94720 (510) 486-6971 segreenberg@lbl.gov For more information on FEMP, please contact: Will Lintner, P.E., CEM Federal Energy Management Program U.S. Department of Energy 1000 Independence Ave. S.W. Washington, D. C. 20585-0121 (202) 586-3120 william.lintner@ee.doe.gov 3 Acknowledgements EPRI: Dennis Symanski, Brian Fortenbery Synapsense: Garret Smith, Patricia Nealon Vigilent: Corinne Vita

32

Pitch-Controlled Variable-Speed Wind Turbine Generation  

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

Pitch-Controlled Variable-Speed Pitch-Controlled Variable-Speed Wind Turbine Generation February 2000 * NREL/CP-500-27143 E. Muljadi and C.P. Butterfield Presented at the 1999 IEEE Industry Applications Society Annual Meeting Phoenix, Arizona October 3-7, 1999 National Renewable Energy Laboratory 1617 Cole Boulevard Golden, Colorado 80401-3393 NREL is a U.S. Department of Energy Laboratory Operated by Midwest Research Institute * * * * Battelle * * * * Bechtel Contract No. DE-AC36-99-GO10337 NOTICE The submitted manuscript has been offered by an employee of the Midwest Research Institute (MRI), a contractor of the US Government under Contract No. DE-AC36-99GO10337. Accordingly, the US Government and MRI retain a nonexclusive royalty-free license to publish or reproduce the published form of this contribution, or allow others to do so, for US Government purposes.

33

Adaptive variable structure control law for a variable speed wind turbine  

Science Conference Proceedings (OSTI)

The efficiency of the wind power conversions systems can be greatly improved using an appropriate control algorithm. In this work, an adaptive robust control for a doubly feed induction generator drive for variable speed wind power generation is described. ... Keywords: modeling and simulation, variable structure control, wind turbine control

Oscar Barambones; Jose Maria Gonzalez De Durana; Patxi Alkorta; Jose Antonio Ramos; Manuel De La Sen

2011-05-01T23:59:59.000Z

34

Performance of twist-coupled blades on variable speed rotors  

DOE Green Energy (OSTI)

The load mitigation and energy capture characteristics of twist-coupled HAWT blades that are mounted on a variable speed rotor are investigated in this paper. These blades are designed to twist toward feather as they bend with pretwist set to achieve a desirable twist distribution at rated power. For this investigation, the ADAMS-WT software has been modified to include blade models with bending-twist coupling. Using twist-coupled and uncoupled models, the ADAMS software is exercised for steady wind environments to generate C{sub p} curves at a number of operating speeds to compare the efficiencies of the two models. The ADAMS software is also used to generate the response of a twist-coupled variable speed rotor to a spectrum of stochastic wind time series. This spectrum contains time series with two mean wind speeds at two turbulence levels. Power control is achieved by imposing a reactive torque on the low speed shaft proportional to the RPM squared with the coefficient specified so that the rotor operates at peak efficiency in the linear aerodynamic range, and by limiting the maximum RPM to take advantage of the stall controlled nature of the rotor. Fatigue calculations are done for the generated load histories using a range of material exponents that represent materials from welded steel to aluminum to composites, and results are compared with the damage computed for the rotor without twist-coupling. Results indicate that significant reductions in damage are achieved across the spectrum of applied wind loading without any degradation in power production.

Lobitz, D.W.; Veers, P.S.; Laino, D.J.

1999-12-07T23:59:59.000Z

35

Best Practices for Energy Efficient Cleanrooms Efficient HVAC Systems: Variable-Speed-Drive Chillers  

E-Print Network (OSTI)

resource/24/ ASHRAE handbook – HVAC systems and equipments.Efficient Cleanrooms Efficient HVAC Systems: Variable-Speed-Efficient Cleanrooms Efficient HVAC Water Systems: Variable-

Xu, Tengfang

2005-01-01T23:59:59.000Z

36

Maximizing Energy Capture of Fixed-Pitch Variable-Speed Wind Turbines  

DOE Green Energy (OSTI)

Field tests of a variable-speed, stall-regulated wind turbine were conducted at a US Department of Energy Laboratory. A variable-speed generating system, comprising a doubly-fed generator and series-resonant power converter, was installed on a 275-kW, downwind, two-blade wind turbine. Gearbox, generator, and converter efficiency were measured in the laboratory so that rotor aerodynamic efficiency could be determined from field measurement of generator power. The turbine was operated at several discrete rotational speeds to develop power curves for use in formulating variable-speed control strategies. Test results for fixed-speed and variable-speed operation are presented along with discussion and comparison of the variable-speed control methodologies. Where possible, comparisons between fixed-speed and variable-speed operation are shown.

Pierce, K.; Migliore, P.

2000-08-01T23:59:59.000Z

37

A neural network control strategy for improved energy capture on a variable-speed wind turbine  

Science Conference Proceedings (OSTI)

Pitch control has so far been the dominating method for power control in modern variable speed wind turbines. This paper proposes an improved control technique for pitching the blades of a variable speed wind turbine, using Artificial Neural Networks ... Keywords: artificial neural networks, control trajectories, pitch control, variable-speed wind turbines

António F. Silva; Fernando A. Castro; José N. Fidalgo

2005-06-01T23:59:59.000Z

38

Design of low speed axial flux permanent magnet generators for marine current application.  

E-Print Network (OSTI)

??Thesis (M.Eng. – Memorial University of Newfoundland, 2010. Engineering and Applied Science The aim of this research work is to design, built and test low speed… (more)

Moury, Sanjida, 1983-

2010-01-01T23:59:59.000Z

39

Variable speed constant frequency constant voltage alternator. Annual report  

DOE Green Energy (OSTI)

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

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

1980-07-01T23:59:59.000Z

40

High speed internal permanent magnet machine and method of manufacturing the same  

Science Conference Proceedings (OSTI)

An internal permanent magnet (IPM) machine is provided. The IPM machine includes a stator assembly and a stator core. The stator core also includes multiple stator teeth. The stator assembly is further configured with stator windings to generate a magnetic field when excited with alternating currents and extends along a longitudinal axis with an inner surface defining a cavity. The IPM machine also includes a rotor assembly and a rotor core. The rotor core is disposed inside the cavity and configured to rotate about the longitudinal axis. The rotor assembly further includes a shaft. The shaft further includes multiple protrusions alternately arranged relative to multiple bottom structures provided on the shaft. The rotor assembly also includes multiple stacks of laminations disposed on the protrusions and dovetailed circumferentially around the shaft. The rotor assembly further includes multiple permanent magnets for generating a magnetic field, which interacts with the stator magnetic field to produce torque. The permanent magnets are disposed between the stacks. The rotor assembly also includes multiple bottom wedges disposed on the bottom structures of the shaft and configured to hold the multiple stacks and the multiple permanent magnets.

Alexander, James Pellegrino (Ballston Lake, NY); EL-Refaie, Ayman Mohamed Fawzi (Niskayuna, NY); Lokhandwalla, Murtuza (Clifton Park, NY); Shah, Manoj Ramprasad (Latham, NY); VanDam, Jeremy Daniel (West Coxsackie, NY)

2011-09-13T23:59:59.000Z

Note: This page contains sample records for the topic "variable speed permanent" 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

Variable Speed Drive Volumetric Tracking (VSDVT) for Airflow Control in Variable Air Volume (VAV) Systems  

E-Print Network (OSTI)

An airflow control method has been developed for variable air volume (VAV) systems. This airflow control method is named VSD volumetric tracking (VSDVT) since both the supply and return airflows are determined using signals of the variable speed drives (VSD) instead of the flow stations. Its performance is studied and compared with the fan tracking (FT) method using model simulations. The VSDVT maintains a constant building pressure and the required outside airflow under all load conditions, reduces the annual return air fan energy by up to 50%, and the annual supply air fan energy by up to 30%. This paper presents the VSDVT method, the system models, and the simulation results.

Liu, M.

2002-01-01T23:59:59.000Z

42

Optimal design of a high-speed slotless permanent magnet synchronous generator with soft magnetic composite stator yoke and rectifier load  

Science Conference Proceedings (OSTI)

This paper presents a specific design methodology of a DC generation system using a high-speed slotless generator with surface-mounted magnets and soft magnetic composite (SMC) stator yoke connected to a rectifier. The method is based on an analytical ... Keywords: Eddy currents, High-speed generation system, Optimal design, Permanent magnet machine, Soft magnetic composite material

Ahmed Chebak; Philippe Viarouge; Jérôme Cros

2010-10-01T23:59:59.000Z

43

Variable speed wind turbine generator with zero-sequence filter  

DOE Patents (OSTI)

A variable speed wind turbine generator system to convert mechanical power into electrical power or energy and to recover the electrical power or energy in the form of three phase alternating current and return the power or energy to a utility or other load with single phase sinusoidal waveform at sixty (60) hertz and unity power factor includes an excitation controller for generating three phase commanded current, a generator, and a zero sequence filter. Each commanded current signal includes two components: a positive sequence variable frequency current signal to provide the balanced three phase excitation currents required in the stator windings of the generator to generate the rotating magnetic field needed to recover an optimum level of real power from the generator; and a zero frequency sixty (60) hertz current signal to allow the real power generated by the generator to be supplied to the utility. The positive sequence current signals are balanced three phase signals and are prevented from entering the utility by the zero sequence filter. The zero sequence current signals have zero phase displacement from each other and are prevented from entering the generator by the star connected stator windings. The zero sequence filter allows the zero sequence current signals to pass through to deliver power to the utility. 14 figs.

Muljadi, E.

1998-08-25T23:59:59.000Z

44

Variable Speed Wind Turbine Generator with Zero-sequence Filter  

DOE Patents (OSTI)

A variable speed wind turbine generator system to convert mechanical power into electrical power or energy and to recover the electrical power or energy in the form of three phase alternating current and return the power or energy to a utility or other load with single phase sinusoidal waveform at sixty (60) hertz and unity power factor includes an excitation controller for generating three phase commanded current, a generator, and a zero sequence filter. Each commanded current signal includes two components: a positive sequence variable frequency current signal to provide the balanced three phase excitation currents required in the stator windings of the generator to generate the rotating magnetic field needed to recover an optimum level of real power from the generator; and a zero frequency sixty (60) hertz current signal to allow the real power generated by the generator to be supplied to the utility. The positive sequence current signals are balanced three phase signals and are prevented from entering the utility by the zero sequence filter. The zero sequence current signals have zero phase displacement from each other and are prevented from entering the generator by the star connected stator windings. The zero sequence filter allows the zero sequence current signals to pass through to deliver power to the utility.

Muljadi, Eduard (Golden, CO)

1998-08-25T23:59:59.000Z

45

Variable speed wind turbine generator with zero-sequence filter  

DOE Patents (OSTI)

A variable speed wind turbine generator system to convert mechanical power into electrical power or energy and to recover the electrical power or energy in the form of three phase alternating current and return the power or energy to a utility or other load with single phase sinusoidal waveform at sixty (60) hertz and unity power factor includes an excitation controller for generating three phase commanded current, a generator, and a zero sequence filter. Each commanded current signal includes two components: a positive sequence variable frequency current signal to provide the balanced three phase excitation currents required in the stator windings of the generator to generate the rotating magnetic field needed to recover an optimum level of real power from the generator; and a zero frequency sixty (60) hertz current signal to allow the real power generated by the generator to be supplied to the utility. The positive sequence current signals are balanced three phase signals and are prevented from entering the utility by the zero sequence filter. The zero sequence current signals have zero phase displacement from each other and are prevented from entering the generator by the star connected stator windings. The zero sequence filter allows the zero sequence current signals to pass through to deliver power to the utility.

Muljadi, Eduard (Golden, CO)

1998-01-01T23:59:59.000Z

46

Advanced Variable Speed Air-Source Integrated Heat Pumps Research Project |  

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

Advanced Variable Speed Air-Source Advanced Variable Speed Air-Source Integrated Heat Pumps Research Project Advanced Variable Speed Air-Source Integrated Heat Pumps Research Project The U.S. Department of Energy is currently conducting research into advanced variable speed air-source integrated heat pumps (AS-IHPs). Project Description This project seeks to develop AS-IHP products for the larger air-source system market. Development focuses on a fully variable capacity or variable speed AS-IHP option. Project Partners Research is being undertaken through a cooperative research and development agreement (CRADA) between the Department of Energy, Oak Ridge National Laboratory, and a CRADA partner. Project Goals The goal of this project is the development of a fully variable-speed version of an AS-IHP product that can provide heating, ventilation, and air

47

Best Practices for Energy Efficient Cleanrooms Efficient HVAC Systems: Variable-Speed-Drive Chillers  

E-Print Network (OSTI)

LBNL-58636 Best Practices for Energy Efficient Cleanrooms Efficient HVAC Systems: Variable Efficient Cleanrooms Efficient HVAC Water Systems: Variable-Speed-Drive Chillers Tengfang Xu Contents HVAC.................................................................................................................................... 6 #12;HVAC Water Systems Variable-Speed-Drive Chillers Summary Cleanroom energy benchmarking data

48

How to Avoid Overestimating Variable Speed Drive Savings  

E-Print Network (OSTI)

This paper addresses eight factors that can cause incorrect and often excessive savings estimates for pump and fan variable speed drive applications. To avoid overestimating savings: 1. Identify system elements that affect head pressure independently of flow rate. 2. Identify system elements that change head pressure in proportion to less than the square of flow rate. 3. Account for dynamic system elements, especially when in systems with minimum static pressure controls. 4. Consider changes in fan efficiency. 5. Account for decreases in motor efficiency at part load, particularly for smaller motors below about 35 percent load. 6. Recognize that existing part load controls may be more efficient than expected. 7. Account for drive losses. 8. Measure full flow power, rather than assuming it is the same as motor nameplate or design power. For many pump and fan systems, none of the eight factors will apply, or their effects will be negligible. However, analysts should consider their applicability when estimating savings for a particular system. This paper provides tools for accounting for the factors.

Maxwell, J. B.

2005-01-01T23:59:59.000Z

49

An examination of loads and responses of a wind turbine undergoing variable-speed operation  

DOE Green Energy (OSTI)

The National Renewable Energy Laboratory has recently developed the ability to predict turbine loads and responses for machines undergoing variable-speed operation. The wind industry has debated the potential benefits of operating wind turbine sat variable speeds for some time. Turbine system dynamic responses (structural response, resonance, and component interactions) are an important consideration for variable-speed operation of wind turbines. The authors have implemented simple, variable-speed control algorithms for both the FAST and ADAMS dynamics codes. The control algorithm is a simple one, allowing the turbine to track the optimum power coefficient (C{sub p}). The objective of this paper is to show turbine loads and responses for a particular two-bladed, teetering-hub, downwind turbine undergoing variable-speed operation. The authors examined the response of the machine to various turbulent wind inflow conditions. In addition, they compare the structural responses under fixed-speed and variable-speed operation. For this paper, they restrict their comparisons to those wind-speed ranges for which limiting power by some additional control strategy (blade pitch or aileron control, for example) is not necessary. The objective here is to develop a basic understanding of the differences in loads and responses between the fixed-speed and variable-speed operation of this wind turbine configuration.

Wright, A.D.; Buhl, M.L. Jr.; Bir, G.S.

1996-11-01T23:59:59.000Z

50

Doubly Salient Permanent Magnet Motor Development Review  

Science Conference Proceedings (OSTI)

The research of doubly salient permanent magnet motor (DSPM), arises as the emergence of a novel type mechatronic control of AC drive system. Currently, on the international realm, the studies regarding on this kind of motor mainly focus on calculation ... Keywords: Doubly Salient, Permanent Magnet Motor, AC Variable Speed, Magnetic Materials, Switched Reluctance Motor

Lina Yi, Meng Zhao

2013-09-01T23:59:59.000Z

51

Effects of turbulence on power generation for variable-speed wind turbines  

DOE Green Energy (OSTI)

One of the primary advantages of variable-speed wind turbines over fixed-speed turbines should be improved aerodynamic efficiency. With variable-speed generation, in order to maintain a constant ratio of wind speed to tip speed, the wind turbine changes rotor speed as the wind speed changes. In this paper we compare a stall-controlled, variable-speed wind turbine to a fixed-speed turbine. The focus of this paper is to investigate the effects of variable speed on energy capture and its ability to control peak power. We also show the impact of turbulence on energy capture in moderate winds. In this report, we use a dynamic simulator to apply different winds to a wind turbine model. This model incorporates typical inertial and aerodynamic performance characteristics. From this study we found a control strategy that makes it possible to operate a stall-controlled turbine using variable speed to optimize energy capture and to control peak power. We also found that turbulence does not have a significant impact on energy capture.

Muljadi, E.; Butterfield, C.P.; Buhl, M.L. Jr.

1996-11-01T23:59:59.000Z

52

Atmospheric Circulation Effects on Wind Speed Variability at Turbine Height  

Science Conference Proceedings (OSTI)

Mean monthly wind speed at 70 m above ground level is investigated for 11 sites in Minnesota for the period 1995–2003. Wind speeds at these sites show significant spatial and temporal coherence, with prolonged periods of above- and below-normal ...

Katherine Klink

2007-04-01T23:59:59.000Z

53

Research of Speed Ratio Matching Strategies of Hydro-Mechanical Continuously Variable Transmission System for Tractor  

Science Conference Proceedings (OSTI)

To realize the optimal power and best fuel economy performance of engine, the speed ratio matching strategies of tractor with hydro-mechanical continuously variable transmission (HMCVT) system are studied. The engine output torque model and fuel consumption ... Keywords: Tractor, Hydro-mechanical continuously variable transmission, Speed ratio, Matching strategies

Liyou Xu; Zhili Zhou; Fuyi Cao; Mingzhu Zhang

2009-10-01T23:59:59.000Z

54

Sliding Mode Power Control of Variable Speed Wind Energy Conversion Systems  

E-Print Network (OSTI)

Sliding Mode Power Control of Variable Speed Wind Energy Conversion Systems B. Beltran, T. Ahmed power generation in variable speed wind energy conversion systems (VS-WECS). These systems have two (National Renewable Energy Laboratory) wind turbine simulator FAST (Fatigue, Aerodynamics, Structures

Brest, Université de

55

Modeling and design of control system for variable speed wind turbine in all operating region  

Science Conference Proceedings (OSTI)

In order to get the maximum power from the wind, the variable-speed wind turbine should run at different speed when wind speed changes. In this paper a control system is introduced to get this purpose base on establishing the three-mass model of the ... Keywords: doubly-fed induction generator (DFIG), feed-forward compensator, loop-shaping, pitch controller, speed controller, three-mass model, wind turbine

Wu Dingguo; Wang Zhixin

2008-05-01T23:59:59.000Z

56

Ultra-high speed permanent magnet axial gap alternator with multiple stators  

DOE Patents (OSTI)

An ultra-high speed, axial gap alternator that can provide an output to a plurality of loads, the alternator providing magnetic isolation such that operating conditions in one load will not affect operating conditions of another load. This improved alternator uses a rotor member disposed between a pair of stator members, with magnets disposed in each of the rotor member surfaces facing the stator members. The magnets in one surface of the rotor member, which alternate in polarity, are isolated from the magnets in the other surface of the rotor member by a disk of magnetic material disposed between the two sets of magents. In the preferred embodiment, this disk of magnetic material is laminated between two layers of non-magnetic material that support the magnets, and the magnetic material has a peripheral rim that extends to both surfaces of the rotor member to enhance the structural integrity. The stator members are substantially conventional in construction in that equally-spaced and radially-oriented slots are provided, and winding members are laid in these slots. A unit with multiple rotor members and stator members is also described.

Hawsey, Robert A. (Oak Ridge, TN); Bailey, J. Milton (Knoxville, TN)

1991-01-01T23:59:59.000Z

57

Damage measurements on the NWTC direct-drive, variable-speed test bed  

SciTech Connect

The NWTC (National Wind Technology Center) Variable-Speed Test Bed turbine is a three-bladed, 10-meter, downwind machine that can be run in either fixed-speed or variable-speed mode. In the variable-speed mode, the generator torque is regulated, using a discrete-stepped load bank to maximize the turbine`s power coefficient. At rated power, a second control loop that uses blade pitch to maintain rotor speed essentially as before, i.e., using the load bank to maintain either generator power or (optionally) generator torque. In this paper, the authors will use this turbine to study the effect of variable-speed operation on blade damage. Using time-series data obtained from blade flap and edge strain gauges, the load spectrum for the turbine is developed using rainflow counting techniques. Miner`s rule is then used to determine the damage rates for variable-speed and fixed-speed operation. The results illustrate that the controller algorithm used with this turbine introduces relatively large load cycles into the blade that significantly reduce its service lifetime, while power production is only marginally increased.

Sutherland, H.J. [Sandia National Lab., Albuquerque, NM (United States); Carlin, P.W. [National Renewable Energy Lab., Golden, CO (United States)

1998-12-31T23:59:59.000Z

58

Stability analysis of a variable-speed wind turbine  

DOE Green Energy (OSTI)

This paper examines the elastomechanical stability of a four-bladed wind turbine over a specific rotor speed range. Stability modes, frequencies, and dampings are extracted using a specialized modal processor developed at NREL that post-processes the response data generated by the ADAMS simulation code. The processor can analyze a turbine with an arbitrary number of rotor blades and offers a novel capability of isolating stability modes that become locked at a single frequency. Results indicate that over a certain rotor speed range, the tower lateral mode and the rotor regressive in-plane mode coalesce, resulting in a self-excited instability. Additional results show the effect of tower and nacelle parameters on the stability boundaries.

Bir, G.S.; Wright, A.D.; Butterfield, C.P.

1996-10-01T23:59:59.000Z

59

Energy Implications of Retrofitting Retail Sector Rooftop Units with Stepped-Speed and Variable-Speed Functionality  

Science Conference Proceedings (OSTI)

Commercial retailers understand that retrofitting constant-speed RTU fan motors with stepped- or variable-speed alternatives could save significant energy in most U.S. climate zones. However, they lack supporting data, both real-world and simulation based, on the cost effectiveness and climate zone-specific energy savings associated with this measure. Thus, building managers and engineers have been unable to present a compelling business case for fan motor upgrades to upper management. This study uses whole-building energy simulation to estimate the energy impact of this type of measure so retailers can determine its economic feasibility.

Studer, D.; Romero, R.; Herrmann, L.; Benne, K.

2012-04-01T23:59:59.000Z

60

EFFECT OF PITCH CONTROL AND POWER CONDITIONING ON POWER QUALITY OF VARIABLE SPEED WIND TURBINE GENERATORS  

E-Print Network (OSTI)

Wind energy is considered as the most viable renewable energy options. In a renewable energy system more energy from the wind. One of the options is to use the variable speed wind turbine-speed wind turbine system for transient studies are discussed in this paper. The performance of wind energy

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


61

HEAT PUMP AND AIR CONDITIONING SYSTEM ANALYSIS BASED ON VARIABLE SPEED COMPRESSOR.  

E-Print Network (OSTI)

??Mechanical Engineering M.S.E. Experiments were carried out to investigate the effect of ambient air temperatures on the heat pump performance using a variable speed compressor.… (more)

Zhang, Hao

2010-01-01T23:59:59.000Z

62

A fuzzy logic controller to increase fault ride-through capability of variable speed wind turbines  

Science Conference Proceedings (OSTI)

A fuzzy controller for improving Fault Ride-Through (FRT) capability of Variable Speed Wind Turbines (WTs) equipped with Doubly Fed Induction Generator (DFIG) is presented. The controller is designed in order to compensate the voltage at the Point of ...

Geev Mokryani, Pierluigi Siano, Antonio Piccolo, Vito Calderaro

2012-01-01T23:59:59.000Z

63

The effects of variable speed and drive train component efficiencies on wind turbine energy capture  

SciTech Connect

A wind turbine rotor achieves optimal aerodynamic efficiency at a single tip-speed ratio (TSR). To maintain that optimal TSR and maximize energy capture in the stochastic wind environment, it is necessary to employ variable-speed operation. Conventional constant-speed wind turbines have, in the past, been converted into variable-speed turbines by attaching power electronics to the conventional induction generator and gearbox drive train. Such turbines have shown marginal, if any, improvement in energy capture over their constant-speed counterparts. These discrepancies have been shown to be the result of drive train components that are not optimized for variable-speed operation. Traditional drive trains and power electronic converters are designed to achieve maximum efficiency at full load and speed. However, the main energy producing winds operate the turbine at light load for long periods of time. Because of this, significant losses to efficiency occur. This investigation employs a quasi-static model to demonstrate the dramatic effect that component efficiency curves can have on overall annual energy capture.

Fingersh, L.J.; Robinson, M.C.

1998-05-01T23:59:59.000Z

64

Low Wind Speed Technology Phase II: Investigation of the Application of Medium-Voltage Variable-Speed Drive Technology to Improve the Cost of Energy from Low Wind Speed Turbines; Behnke, Erdman and Whitaker Engineering, Inc.  

SciTech Connect

This fact sheet describes a subcontract with Behnke, Erdman & Whitaker Engineering, Inc. to test the feasibility of applying medium-voltage variable-speed drive technology to low wind speed turbines.

2006-03-01T23:59:59.000Z

65

On Structure and History of Space-time with Variable Speed of Light  

E-Print Network (OSTI)

We apply the variable speed of light into general relativity in order to solve the problems we met in the standard cosmology. We're surprised to find that, the results from the general relativity in cosmology are exactly the same as those we got from Newtonian dynamics. The relation between the Newtonian dynamics and the relativistic dynamics can be demonstrated with the variable speed of light. With this approach, some problems in the standard cosmology such as the flatness problem and the horizon problem doesn't arise any more. All the cosmological results and the physical results are reasonable and natural. There are no any difficulties in the standard cosmology.

Guoyou Huang

2004-10-15T23:59:59.000Z

66

Performance simulation of R410A air conditioning system with variable speeds  

Science Conference Proceedings (OSTI)

With the implementation of "Montreal protocol on substances that deplete the ozone layer", HCFCs especially R22 will be phased out. R410A (R32/R125,50/50wt%), as one alternative of R22, is a promising refrigerant for air conditioning ... Keywords: R410A, air conditioning, electronic expansion valve, performance, refrigerants, system simulation, variable speeds

Zaoxiao Zhang; Yongzhang Yu; Leping Zhang

2004-12-01T23:59:59.000Z

67

Modelling and Analysis of Variable Speed Wind Turbines with Induction Generator during Grid  

E-Print Network (OSTI)

Modelling and Analysis of Variable Speed Wind Turbines with Induction Generator during Grid Fault Wind Turbines with Induction Generator during Grid Fault by Sigrid M. Bolik Institute of Energy turbine technology has undergone rapid developments. Growth in size and the optimization of wind turbines

Hansen, René Rydhof

68

A variable speed wind generator maximum power tracking based on adaptative neuro-fuzzy inference system  

Science Conference Proceedings (OSTI)

The power from wind varies depending on the environmental factors. Many methods have been proposed to locate and track the maximum power point (MPPT) of the wind, such as the fuzzy logic (FL), artificial neural network (ANN) and neuro-fuzzy. In this ... Keywords: ANFIS, MPPT, Power generation, Variable speed wind generator, Wind energy

A. Meharrar; M. Tioursi; M. Hatti; A. Boudghène Stambouli

2011-06-01T23:59:59.000Z

69

0-7803-9280-9/05/$20.00 2005 IEEE. 603 Design of a High-Speed Permanent Magnet Motor  

E-Print Network (OSTI)

of a 500 W permanent magnet (PM) machine used to drive the air- compressor of a 5 kW fuel cell (FC machine presented in this paper have theoretically more than 25 % of its working area with an efficiency (oxygen) supply, which often consists of compressor, possibly coupled to a turbine; - the humidifier

Paris-Sud XI, Université de

70

Model of variable speed constant frequency double fed wind power generation system and analysis of its operating performance  

Science Conference Proceedings (OSTI)

Structure of variable speed constant frequency double fed wind power generation system (WPGS) was analyzed, and its model was established. Maximum power point tracking (MPPT) control, constant power control and vector control for WPGS were discussed. ... Keywords: operating performance, variable speed constant frequency, vector control, wind power generation system

Pan Tinglong; Ji Zhicheng

2009-06-01T23:59:59.000Z

71

Methods for Increasing Region 2 Power Capture on a Variable Speed HAWT: Preprint  

DOE Green Energy (OSTI)

The standard region 2 control scheme for a variable speed wind turbine, tc= kw2, has several shortcomings that can result in significant power loss. The first of these is that there is no accurate way to determine the gain k; modeling programs are not accurate enough to represent all of the complex aerodynamics, and these aerodynamics change over time. Furthermore, it is not certain whether the value of k used in the standard control even provides for the maximum energy capture under real-world turbulent conditions. New control ideas are introduced to address these issues. First, it is shown in simulation that using smaller values of k than the standard can result in increased power capture. Second, an optimally tracking rotor control scheme improves upon the standard scheme by assisting the rotor speed in tracking wind speed fluctuations more rapidly. Finally, an adaptive control scheme is proposed that allows for maximum power capture despite parameter uncertainty.

Johnson, K. E.; Fingersh, L. J.; Balas, M. J.; Pao, L. Y.

2003-11-01T23:59:59.000Z

72

Systematic approach for PID controller design for pitch-regulated, variable-speed wind turbines  

DOE Green Energy (OSTI)

Variable-speed, horizontal axis wind turbines use blade-pitch control to meet specified objectives for three regions of operation. This paper focuses on controller design for the constant power production regime. A simple, rigid, non-linear turbine model was used to systematically perform trade-off studies between two performance metrics. Minimization of both the deviation of the rotor speed from the desired speed and the motion of the actuator is desired. The robust nature of the proportional-integral-derivative (PID) controller is illustrated, and optimal operating conditions are determined. Because numerous simulation runs may be completed in a short time, the relationship of the two opposing metrics is easily visualized. 2 refs., 9 figs.

Hand, M.M. [National Renewable Energy Lab., Golden, CO (United States); Balas, M.J. [Univ. of Colorado, Boulder, CO (United States). Dept. of Aerospace Engineering Sciences

1997-11-01T23:59:59.000Z

73

Performance Analysis of Air-Source Variable Speed Heat Pumps and Various Electric Water Heating Options  

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

Analysis of Air- Analysis of Air- Source Variable Speed Heat Pumps and Various Electric Water Heating Options Jeffrey Munk Oak Ridge National Laboratory 2 Managed by UT-Battelle for the U.S. Department of Energy Presentation_name Acknowledgements * Tennessee Valley Authority - David Dinse * U.S. Department of Energy * Roderick Jackson * Tony Gehl * Philip Boudreaux * ZEBRAlliance 3 Managed by UT-Battelle for the U.S. Department of Energy Presentation_name Overview * Electric Water Heating Options - Conventional Electric Water Heaters - Heat Pump Water Heaters * Air-Source * Ground-Source - Solar Thermal Water Heater * Variable Speed Heat Pumps - Energy Use Analysis - Measured Performance - Operational Characteristics 4 Managed by UT-Battelle for the U.S. Department of Energy Presentation_name Water Heating Options

74

Power-Electronic, Variable-Speed Wind Turbine Development: 1988-1993  

Science Conference Proceedings (OSTI)

A five-year development program culminated in the 33M-VS power-electronic, variable-speed turbine, used in a number of wind power plants to offer competitively priced electricity. This report describes turbine development activities from conception through field testing, highlights design decisions that led to the new technology, and provides an overview of the turbine's electrical and mechanical design. An appendix describes technical issues relevant to building a wind power plant using 33M-VS turbines.

1995-11-16T23:59:59.000Z

75

Power applications of high-temperature superconductivity: Variable speed motors, current switches, and energy storage for end use  

DOE Green Energy (OSTI)

The objective of this project is to conduct joint research and development activities related to certain electric power applications of high-temperature superconductivity (HTS). The new superconductors may allow development of an energy-efficient switch to control current to variable speed motors, superconducting magnetic energy storage (SMES) systems, and other power conversion equipment. Motor types that were considered include induction, permanent magnet, and superconducting ac motors. Because it is impractical to experimentally alter certain key design elements in radial-gap motors, experiments were conducted on an axial field superconducting motor prototype using 4 NbTi magnets. Superconducting magnetic energy storage technology with 0.25--5 kWh stored energy was studied as a viable solution to short duration voltage sag problems on the customer side of the electric meter. The technical performance characteristics of the device wee assembled, along with competing technologies such as active power line conditioners with storage, battery-based uninterruptible power supplies, and supercapacitors, and the market potential for SMES was defined. Four reports were prepared summarizing the results of the project.

Hawsey, R.A. [Oak Ridge National Lab., TN (United States); Banerjee, B.B.; Grant, P.M. [Electric Power Research Inst., Palo Alto, CA (United States)

1996-08-01T23:59:59.000Z

76

Nonlinear Dual-Mode Control of Variable-Speed Wind Turbines with Doubly Fed Induction Generators  

E-Print Network (OSTI)

This paper presents a feedback/feedforward nonlinear controller for variable-speed wind turbines with doubly fed induction generators. By appropriately adjusting the rotor voltages and the blade pitch angle, the controller simultaneously enables: (a) control of the active power in both the maximum power tracking and power regulation modes, (b) seamless switching between the two modes, and (c) control of the reactive power so that a desirable power factor is maintained. Unlike many existing designs, the controller is developed based on original, nonlinear, electromechanically-coupled models of wind turbines, without attempting approximate linearization. Its development consists of three steps: (i) employ feedback linearization to exactly cancel some of the nonlinearities and perform arbitrary pole placement, (ii) design a speed controller that makes the rotor angular velocity track a desired reference whenever possible, and (iii) introduce a Lyapunov-like function and present a gradient-based approach for mini...

Tang, Choon Yik; Jiang, John N

2010-01-01T23:59:59.000Z

77

Strategy for the Operation of Cooling Towers with variable Speed Fans  

E-Print Network (OSTI)

Within the SPS Cooling Water Project at CERN aimed at the reduction of water consumption, this primary open cooling loop will be closed and all the primary cooling circuit components will be upgraded to the new required duty and brought to the necessary safety and operability standards. In particular the tower fans will be fitted with variable frequency drives to replace the existing two speed motors. This paper presents a study to optimize the operation of SPS cooling towers taking into account outdoor conditions (wet and dry bulb temperatures) and the entirety of the primary circuit in which they will operate.

Iñigo-Golfín, J

2001-01-01T23:59:59.000Z

78

Increasing the energetic efficiency in producing of electric and thermal power in thermal power plants by using of variable speed  

Science Conference Proceedings (OSTI)

In this work is presenting a theoretical analysis and an experimental application of the energetic efficiency increase by using of variable-speed AC electric drive systems in a thermal power plant that produces electric and thermal power. Are presented ... Keywords: asynchronous motor, district heating system, energetic efficiency, harmonic distorsion generated by adjustable speed drives, pumping station, static frequency converter, testing

Sorin Ioan Deaconu; Gabriel Nicolae Popa; Iosif Popa

2008-09-01T23:59:59.000Z

79

Fixed-Speed and Variable-Slip Wind Turbines Providing Spinning Reserves to the Grid: Preprint  

DOE Green Energy (OSTI)

As the level of wind penetration increases, wind turbine technology must move from merely generating power from wind to taking a role in supporting the bulk power system. Wind turbines should have the capability to provide inertial response and primary frequency (governor) response so they can support the frequency stability of the grid. To provide governor response, wind turbines should be able to generate less power than the available wind power and hold the rest in reserve, ready to be accessed as needed. This paper explores several ways to control wind turbine output to enable reserve-holding capability. This paper focuses on fixed-speed (also known as Type 1) and variable-slip (also known as Type 2) turbines.

Muljadi, E.; Singh, M.; Gevorgian, V.

2012-11-01T23:59:59.000Z

80

Distrubance Tracking and Blade Load Control of Wind Turbines in Variable-Speed Operation: Preprint  

DOE Green Energy (OSTI)

A composite state-space controller was developed for a multi-objective problem in the variable-speed operation of wind turbines. Disturbance Tracking Control theory was applied to the design of a torque controller to optimize energy capture under the influence of persistent wind disturbances. A limitation in the theory for common multi-state models is described, which led to the design of a complementary pitch controller. The goal of the independent blade pitch design was to minimize blade root fatigue loads. Simulation results indicate an 11% reduction in fatigue damage using the proposed controllers, compared to a conventional torque-only design. Meanwhile, energy capture is almost identical, partly because of nonlinear effects.

Stol, K. A.

2003-01-01T23:59:59.000Z

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


81

Novel sensorless generator control and grid fault ride-through strategies for variable-speed wind turbines and implementation on a new real-time simulation platform.  

E-Print Network (OSTI)

??The usage of MW-size variable-speed wind turbines as sources of energy has increased significantly during the last decade. Advantages over fixed-speed wind turbines include more… (more)

Yang, Sheng

2010-01-01T23:59:59.000Z

82

IEEE TRANSACTIONS ON ENERGY CONVERSION, VOL. 20, NO. 1, MARCH 2005 121 Minimization of Iron Losses of Permanent  

E-Print Network (OSTI)

magnet machines, synchronous machines. I. INTRODUCTION ELECTRIC motor-driven equipment utilizes them is to use variable speed permanent magnet (PM) synchronous motors. With proper design, a PM of Permanent Magnet Synchronous Machines Chunting Chris Mi, Senior Member, IEEE, Gordon R. Slemon, Life Fellow

Mi, Chunting "Chris"

83

Efficient Low-Lift cooling with Radiant Distribution, Thermal Storage and Variable-Speed Chiller Controls  

DOE Green Energy (OSTI)

The U.S. Department of Energy’s Building Technologies Program goal is to develop cost-effective technologies and building practices that will enable the design and construction of net-zero energy buildings by 2025. To support this goal, Pacific Northwest National Laboratory evaluated an integrated technology that through utilization of synergies between emerging heating, ventilation and air conditioning systems can significantly reduce energy consumption in buildings. This set consists of thermal storage, dedicated outdoor air system, radiant heating/cooling with a variable speed low-lift-optimized vapor compression system. The results show that the low-lift cooling system provides significant energy savings in many building types and climates locations. This market represents well over half of the entire U.S. commercial building sector. This analysis shows that significant cooling system efficiency gains can be achieved by integrating low-lift cooling technologies. The cooling energy savings for a standard-performance building range from 37% to 84% and, for a high-performance building, from -9% to 70%.

Katipamula, Srinivas; Armstrong, Peter; Wang, Weimin; Fernandez, Nicholas

2010-05-31T23:59:59.000Z

84

Testing requirements for variable-speed generating technology for wind turbine applications. Final report  

Science Conference Proceedings (OSTI)

Guidelines for evaluating the impacts of integrating variable-speed, constant-frequency (VSCF) wind turbines into electric utility systems have been proposed based upon prior test experiences with the NASA VSCF system and the expected performance of the Westinghouse and OMNION VSCF systems. The NASA and Westinghouse VSCF generating systems use a wound rotor induction generator and a cycloconverter, while the OMNION system uses a wound rotor induction generator and a dc-current link converter. The design of VSCF/utility system interface requirements and test plans is based on utility system electrical issues such as utility system control and operation, protection, voltage/reactive power management, power quality, and reliability. A framework for testing VSCF concepts is proposed which includes a three stage process: modeling of the system to analyze design alternatives and simulate disturbances that could be harmful to the actual system; laboratory testing which involves the use of the system under controlled conditions; and field testing to collect data under actual conditions to validate models and analyze the wind turbine behavior.

Herrera, J.I.

1986-05-01T23:59:59.000Z

85

Efficient Low-Lift cooling with Radiant Distribution, Thermal Storage and Variable-Speed Chiller Controls Part II: Annual Energy Use and Savings  

DOE Green Energy (OSTI)

This paper evaluates the potential cooling efficiency improvements to be gained by integrating radiant cooling, cool storage, and variable-speed compressor and transport motor controls.

Armstrong, Peter; Jiang, Wei; Winiarski, David W.; Katipamula, Srinivas; Norford, L. K.

2009-03-31T23:59:59.000Z

86

Resonant Vibrations Resulting from the Re-Engineering of a Constant-Speed 2-Bladed Turbine to a Variable-Speed 3-Bladed Turbine  

SciTech Connect

The CART3 (Controls Advanced Research Turbine, 3-bladed) at the National Wind Technology Center has recently been converted from a 2-bladed constant speed machine to a 3-bladed variable speed machine designed specically for controls research. The purpose of this conversion was to develop an advanced controls field-testing platform which has the more typical 3-bladed configuration. A result of this conversion was the emergence of several resonant vibrations, some of which initially prevented operation of the turbine until they could be explained and resolved. In this paper, the investigations into these vibrations are presented as 'lessons-learned'. Additionally, a frequency-domain technique called waterfall plotting is discussed and its usefulness in this research is illustrated.

Fleming, P.; Wright, A. D.; Finersh, L. J.

2010-12-01T23:59:59.000Z

87

Resonant Vibrations Resulting from the Re-Engineering of a Constant-Speed 2-Bladed Turbine to a Variable-Speed 3-Bladed Turbine  

DOE Green Energy (OSTI)

The CART3 (Controls Advanced Research Turbine, 3-bladed) at the National Wind Technology Center has recently been converted from a 2-bladed constant speed machine to a 3-bladed variable speed machine designed specically for controls research. The purpose of this conversion was to develop an advanced controls field-testing platform which has the more typical 3-bladed configuration. A result of this conversion was the emergence of several resonant vibrations, some of which initially prevented operation of the turbine until they could be explained and resolved. In this paper, the investigations into these vibrations are presented as 'lessons-learned'. Additionally, a frequency-domain technique called waterfall plotting is discussed and its usefulness in this research is illustrated.

Fleming, P.; Wright, A. D.; Finersh, L. J.

2010-12-01T23:59:59.000Z

88

Pitch Angle Control of Variable Low Rated Speed Wind Turbine Using Fuzzy Logic Control  

E-Print Network (OSTI)

Abstract — Pitch angle control of wind turbine has been used widely to reduce torque and output power variation in high rated wind speed areas. It is a challenge to maximize available energy in the low rated wind speed areas. In this paper, a wind turbine prototype with a pitch angle control based on fuzzy logic to maximize the output power is built and demonstrated. In the varying low rated wind speed of 4-6 m/s, the use of fuzzy logic controller can maximize the average output power of 14.5 watt compared to 14.0 watt at a fixed pitch angle of the blade. Implementation of pitch angle fuzzy logic-based control to the wind turbine is suitable for the low rated wind speed areas. Index Terms — low rated wind speed areas, pitch angle control, fuzzy logic, wind turbine. T I.

A. Musyafa; A. Harika; I. M. Y. Negara; I. Rob

2010-01-01T23:59:59.000Z

89

Efficient Low-Lift Cooling with Radiant Distribution, Thermal Storage and Variable-Speed Chiller Controls Part I: Component and Subsystem Models  

DOE Green Energy (OSTI)

this paper develops component and subsystem models used to evaluat4e the performance of a low-lift cooling system with an air-colled chiller optimized for variable-speed and low-pressure-ratio operation, a hydronic radient distribution system, variable-speed transport miotor controls, and peak-shifting controls.

Armstrong, Peter; Jiang, Wei; Winiarski, David W.; Katipamula, Srinivas; Norford, L. K.; Willingham, ryan

2009-03-31T23:59:59.000Z

90

Control algorithms for effective operation of variable-speed wind turbines  

DOE Green Energy (OSTI)

This report describes a computer code, called ASYM and provides results from its application in simulating the control of the 34-m Test Bed vertical-axis wind turbine (VAWT) in Bushland, Texas. The code synthesizes dynamic wind speeds on a second-by-second basis in the time domain. The wind speeds conform to a predetermined spectral content governed by the hourly average wind speed that prevails at each hour of the simulation. The hourly average values are selected in a probabilistic sense through the application of Markov chains, but their cumulative frequency of occurrence conforms to a Rayleigh distribution that is governed by the mean annual wind speed of the site selected. The simulated wind speeds then drive a series of control algorithms that enable the code to predict key operational parameters such as number of annual starts and stops, annual energy production, and annual fatigue damage at a critically stressed joint on the wind turbine. This report also presents results from the application of ASYM that pertain to low wind speed cut-in and cut-out conditions and controlled operation near critical speed ranges that excite structural vibrations that can lead to accelerated fatigue damage.

Not Available

1993-10-01T23:59:59.000Z

91

The study of multimode power control system for MW variable-speed wind turbine  

Science Conference Proceedings (OSTI)

Wind energy is a viable option to complement other types of pollution-free generation. In the past constant-speed wind turbine is used for the limitation of the control technology and manufacturing technology. But this kind wind turbine has low efficiency ... Keywords: feed-forward compensator, loop-shaping, multimode power control system, pitch controller, speed controller, the shaft system model, wind turbine

Dingguo Wu; Zhixin Wang

2008-10-01T23:59:59.000Z

92

The VSL Discussion: What Does Variable Speed of Light Mean and Should we be Allowed to Think About ?  

E-Print Network (OSTI)

In the past years, variable speed of light (VSL) theories have been of growing interest but also a subject of controversial discussion. They have been accused both for tautologies and for violating special relativity, and concerns have been expressed about the validity of such approaches in general (e.g. Ellis, astro-ph/0703751). Without trying completeness on the issue, the example of Einstein's VSL attempts (1911) and Dicke's `electromagnetic' theory (1957) are urges to give some comments on the above criticism.

Alexander Unzicker

2007-08-21T23:59:59.000Z

93

Analysis of the electrical harmonic characteristics of a slip recovery variable speed generating system for wind turbine applications  

SciTech Connect

Variable speed electric generating technology can enhance the general use of wind energy in electric utility applications. This enhancement results from two characteristic properties of variable speed wind turbine generators: an improvement in drive train damping characteristics, which results in reduced structural loading on the entire wind turbine system, and an improvement in the overall efficiency by using a more sophisticated electrical generator. Electronic converter systems are the focus of this investigation -- in particular, the properties of a wound-rotor induction generator with the slip recovery system and direct-current link converter. Experience with solid-state converter systems in large wind turbines is extremely limited. This report presents measurements of electrical performances of the slip recovery system and is limited to the terminal characteristics of the system. Variable speed generating systems working effectively in utility applications will require a satisfactory interface between the turbine/generator pair and the utility network. The electrical testing described herein focuses largely on the interface characteristics of the generating system. A MOD-O wind turbine was connected to a very strong system; thus, the voltage distortion was low and the total harmonic distortion in the utility voltage was less than 3% (within the 5% limit required by most utilities). The largest voltage component of a frequency below 60 Hz was 40 dB down from the 60-Hz< component. 8 refs., 14 figs., 8 tabs.

Herrera, J.I.; Reddoch, T.W.

1988-02-01T23:59:59.000Z

94

Unifluxor: a permanent memory element  

Science Conference Proceedings (OSTI)

The Unifluxor is a new binary permanent memory element which appears to have the advantages of high-speed operation, easy fabrication, and low cost. Unlike cores, twistors, capacitors, and other commonly used memory devices, the Unifluxor does not depend ...

A. M. Renard; W. J. Neumann

1960-05-01T23:59:59.000Z

95

Analytical approach to sensitivity analysis of flutter speed in bridges considering variable deck mass  

Science Conference Proceedings (OSTI)

Design techniques based upon sensitivity analysis are not usual in the current design of suspension bridges. However, sensitivity analysis has been proved to be a useful tool in the car and aircraft industries. Evaluation of sensitivity analysis is a ... Keywords: Bridge design, Flutter speed, Great Belt Bridge, Parallel processing, Sensitivity analysis, Wind engineering

Félix Nieto; Santiago Hernández; José Á. Jurado; Alejandro Mosquera

2011-04-01T23:59:59.000Z

96

Neuroadaptive speed assistance control of wind turbine with variable ratio gearbox (VRG)  

Science Conference Proceedings (OSTI)

Wind power as a renewable energy source is irregular in occurrence. It is interesting yet challenging to maximize the energy capture from wind. Most existing control methods for wind power generation are traditionally based on wind turbine with fixed ... Keywords: PMSM, neuroadaptive control, speed regulation, wind turbine

Xue-fei Wang; Yong-duan Song; Dan-yong Li; Kai Zhang; Shan Xue; Ming Qin

2012-07-01T23:59:59.000Z

97

Phase Speed Spectra and the Latitude of Surface Westerlies: Interannual Variability and Global Warming Trend  

Science Conference Proceedings (OSTI)

The extratropical annular-mode-like atmospheric responses to ENSO and global warming and the internal variability of annular modes are associated with similar, yet distinct, dynamical characteristics. In particular, La Niña, global warming, and ...

Gang Chen; Jian Lu; Dargan M. W. Frierson

2008-11-01T23:59:59.000Z

98

Utility of Variable Speed Drives for Fish Protection at Cooling Water Intakes  

Science Conference Proceedings (OSTI)

This report reviews the utility of a variable frequency drive (VFD) for reducing cooling water flow and potentially the extent of impingement and entrainment of fish and shellfish at power plant cooling water intakes. Reduction of impingement and entrainment at cooling water intakes is the objective of Clean Water Act 316(b) requirements that are being developed by the U.S. Environmental Protection Agency (EPA).

2010-06-03T23:59:59.000Z

99

Guide to the Industrial Application of Motors and Variable-Speed Drives  

Science Conference Proceedings (OSTI)

This application guide is intended to aid in screening, selecting, and procuring specification processes for variable frequency drive (VFD) installations. It also is intended to provide a comprehensive up-to-date assessment of opportunities to save energy and improve power quality performance with state-of-the-art VFD technologies. The document supplies background information on electric motors and applications, describes VFD topologies, and details procurement specifications and application consideratio...

2001-09-27T23:59:59.000Z

100

Auto-Calibration and Control Strategy Determination for a Variable-Speed Heat Pump Water Heater Using Optimization  

SciTech Connect

This paper introduces applications of the GenOpt optimizer coupled with a vapor compression system model for auto-calibration and control strategy determination towards the development of a variable-speed ground-source heat pump water heating unit. The GenOpt optimizer can be linked with any simulation program using input and output text files. It effectively facilitates optimization runs. Using our GenOpt wrapper program, we can flexibly define objectives for optimizations, targets, and constraints. Those functionalities enable running extensive optimization cases for model calibration, configuration design and control strategy determination. In addition, we describe a methodology to improve prediction accuracy using functional calibration curves. Using the calibrated model, we investigated control strategies of the ground-source heat pump water heater, considering multiple control objectives, covering the entire operation range.

Shen, Bo [ORNL; Abdelaziz, Omar [ORNL; Rice, C Keith [ORNL

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "variable speed permanent" 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

Comparing Two Types of Magnetically- Coupled Adjustable Speed Drives with Variable Frequency Drives in Pump and Fan Applications  

E-Print Network (OSTI)

This paper presents the results from laboratory tests on MagnaDrive Corporations fixed-magnet magnetically-coupled adjustable speed drive (MC-ASD) and Coyote Electronics electromagnetic MC-ASD as compared to a typical variable frequency drive (VFD) for typical fan and pump loads. It also discusses advantages and disadvantages of using mechanical MC-ASD versus VFDs and it provides field experience with VFDs in refrigerated warehouses as well as the fixed magnet MC-ASD in wastewater and other field applications. Laboratory tests for a 50 hp fan retrofit showed electronic VFD savings at 62%, the MagnaDrive Coupling at 39% and PAYBACK Drive at 46%. At $0.06/kWh and list prices, the simple payback for the VFD is 2.4 years, the MagnaDrive is 4.6 years and the PAYBACK is 1.9 years. MagnaDrive has models from 25 to 500 hp while PAYBACK has models from 3 to 200 hp. Contractors to the Northwest Energy Efficiency Alliance have helped to install VFDs for about 300 evaporator fans in over two dozen refrigerated warehouses and to install fixed-magnet MC-ASDs in about 50 applications with about half of these controlling wastewater pumps. The Alliance has no particular field experience with the electcromagnetic coupling. The primary advantages of magnetically coupled adjustable speed drives (MC-ASD) over VFDs come from reduced maintenance, resistance to dirty environments, separation of load vibration from the motor, and less stringent requirements for precise shaft alignment. Field experience indicates reductions in noise and repairs from vibration loads, tolerance of poor electrical power quality, and ease of installation are often more important than energy savings. The MC-ASDs are being used where VFDs have not survived or are considered too complicated.

Anderson, K. J.; Chvala, W. D.

2003-05-01T23:59:59.000Z

102

Low Wind Speed Turbine Project Phase II: The Application of Medium-Voltage Electrical Apparatus to the Class of Variable Speed Multi-Megawatt Low Wind Speed Turbines; 15 June 2004--30 April 2005  

DOE Green Energy (OSTI)

Kilowatt ratings of modern wind turbines have progressed rapidly from 50 kW to 1,800 kW over the past 25 years, with 3.0- to 7.5-MW turbines expected in the next 5 years. The premise of this study is simple: The rapid growth of wind turbine power ratings and the corresponding growth in turbine electrical generation systems and associated controls are quickly making low-voltage (LV) electrical design approaches cost-ineffective. This report provides design detail and compares the cost of energy (COE) between commercial LV-class wind power machines and emerging medium-voltage (MV)-class multi-megawatt wind technology. The key finding is that a 2.5% reduction in the COE can be achieved by moving from LV to MV systems. This is a conservative estimate, with a 3% to 3.5% reduction believed to be attainable once purchase orders to support a 250-turbine/year production level are placed. This evaluation considers capital costs as well as installation, maintenance, and training requirements for wind turbine maintenance personnel. Subsystems investigated include the generator, pendant cables, variable-speed converter, and padmount transformer with switchgear. Both current-source and voltage-source converter/inverter MV topologies are compared against their low-voltage, voltage-source counterparts at the 3.0-, 5.0-, and 7.5-MW levels.

Erdman, W.; Behnke, M.

2005-11-01T23:59:59.000Z

103

Comparison on control strategies of the grid-side converter of variable speed constant frequency doubly-fed wind power generation system  

Science Conference Proceedings (OSTI)

Direct power control, vector control based on d-q synchronous rotating reference frame and ?-? static reference frame for the grid-side converter of variable speed constant frequency doubly-fed wind turbines are analyzed. System simulation ... Keywords: ?-? static reference frame, d-q rotating reference frame, direct power control, doubly-fed wind power generation system, grid-side converter

Xian-Ming Zhou; Ting-Long Pan; Zhi-Cheng Ji

2009-06-01T23:59:59.000Z

104

The Probability Distribution of Sea Surface Wind Speeds: Effects of Variable Surface Stratification and Boundary Layer Thickness  

Science Conference Proceedings (OSTI)

Air–sea exchanges of momentum, energy, and material substances of fundamental importance to the variability of the climate system are mediated by the character of the turbulence in the atmospheric and oceanic boundary layers. Sea surface winds ...

Adam Hugh Monahan

2010-10-01T23:59:59.000Z

105

Axial flux, modular, permanent-magnet generator with a toroidal winding for wind turbine applications  

SciTech Connect

Permanent-magnet generators have been used for wind turbines for many years. Many small wind turbine manufacturers use direct-drive permanent-magnet generators. For wind turbine generators, the design philosophy must cover the following characteristics: low cost, light weight, low speed, high torque, and variable speed generation. The generator is easy to manufacture and the design can be scaled up for a larger size without major retooling. A modular permanent-magnet generator with axial flux direction was chosen. The permanent magnet used is NdFeB or ferrite magnet with flux guide to focus flux density in the air gap. Each unit module of the generator may consist of one, two, or more phases. Each generator can be expanded to two or more unit modules. Each unit module is built from simple modular poles. The stator winding is formed like a torus. Thus, the assembly process is simplified and the winding insertion in the slot is less tedious. The authors built a prototype of one unit module and performed preliminary tests in the laboratory. Follow up tests will be conducted in the lab to improve the design.

Muljadi, E.; Butterfield, C.P.; Wan, Y.H.

1998-07-01T23:59:59.000Z

106

The InterHourly-Variability (IHV) Index of Geomagnetic Activity and its Use in Deriving the Long-term Variation of Solar Wind Speed  

E-Print Network (OSTI)

We describe the derivation of the InterHourly Variability (IHV) index of geomagnetic activity. The IHV-index for a geomagnetic element is mechanically derived from hourly values as the sum of the unsigned differences between adjacent hours over a seven-hour interval centered on local midnight. The index is derived separately for stations in both hemispheres within six longitude sectors using only local night hours. It is intended as a long-term index. Available data allows derivation of the index back well into the 19th century. On a time scale of a 27-day Bartels rotation, IHV averages for stations with corrected geomagnetic latitude less than 55 degrees are strongly correlated with midlatitude range indices. Assuming a constant calibration of the aa-index we find that observed yearly values of aa before the year 1957 are 2.9 nT too small compared to values calculated from IHV using the regression constants based on 1980-2004. We interpret this discrepancy as an indication that the calibration of the aa index is in error before 1957. There is no such problem with the ap index. Rotation averages of IHV are also strongly correlated with solar wind parameters (BV^2). On a time scale of a year combining the IHV-index and the recently-developed Inter-Diurnal Variability (IDV) index (giving B) allows determination of solar wind speed, V, from 1890-present. Over the ~120-year series, the yearly mean solar wind speed varied from a low of 303 km/s in 1902 to a high value of 545 km/s in 2003. The calculated yearly values of the product BV using B and V separately derived from IDV and IHV agree quantitatively with (completely independent) BV derived from the amplitude of the diurnal variation of the H component in the polar caps since 1926 and sporadically beyond.

Leif Svalgaard; Edward W. Cliver

2007-06-07T23:59:59.000Z

107

Model Predictive Control of a Permanent Magnet Synchronous Motor with Experimental Validation  

E-Print Network (OSTI)

Model Predictive Control of a Permanent Magnet Synchronous Motor with Experimental Validation Shan to regulate the speed of a permanent magnet synchronous motor where the design is based on a linearized state rejection, constraints, quadratic programming. 1. Introduction Permanent Magnet Synchronous Motors (PMSMs

108

2528 IEEE TRANSACTIONS ON MAGNETICS, VOL. 43, NO. 6, JUNE 2007 A Highly Efficient 200 000 RPM Permanent Magnet Motor System  

E-Print Network (OSTI)

Permanent Magnet Motor System Limei Zhao1, Chan Ham2, Liping Zheng3, Thomas Wu4, Kalpathy Sundaram4, Jay presents the development of an ultra-high-speed permanent magnet synchronous motor (PMSM) that produces effectiveness. Index Terms--Permanent magnet, motor, stability, ultra-high-speed. I. INTRODUCTION DUE

Wu, Shin-Tson

109

A 200 000 rpm, 2 kW Slotless Permanent Magnet Pierre-Daniel Pfister, Student Member IEEE and Yves Perriard, Senior Member IEEE  

E-Print Network (OSTI)

A 200 000 rpm, 2 kW Slotless Permanent Magnet Motor Pierre-Daniel Pfister, Student Member IEEE high speed (200 krpm, 2 kW) slotless permanent magnet motor, using an analytical model that reached 200 krpm. Index Terms--Very high speed, Slotless permanent magnet motor, Multiphysics analytical

Psaltis, Demetri

110

Permanent Markers Implementation Plan  

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

WIPP 04-3302 WIPP 04-3302 Permanent Markers Implementation Plan August 19, 2004 United States Department of Energy Waste Isolation Pilot Plant Carlsbad Field Office Carlsbad, New Mexico DOE/WIPP 04-3302 ii Permanent Markers Implementation Plan Waste Isolation Pilot Plant Carlsbad, New Mexico August 19, 2004 Prepared for: Washington Regulatory and Environmental Services an affiliate of Washington TRU Solutions, LLC P.O. Box 2078 Carlsbad, New Mexico 88221 Prepared by: John Hart and Associates, P.A. 2815 Candelaria Road, N.W. Albuquerque, New Mexico 87107 (505) 344-7868 DOE/WIPP 04-3302 iii Table of Contents Table of Contents.................................................................................................

111

Permanent Magnet Materials  

Science Conference Proceedings (OSTI)

Table 4   Applications of permanent magnet materials...material Primary reason for selection Alternative material Condition or reason favoring selection of alternative material Aircraft magnetos, military or civilian SmCo Maximum energy per unit volume Cast Alnico 5 Availability or cost restraint Alternators SmCo Compactness and reliability Ferrite...

112

Permanent Magnet Materials  

Science Conference Proceedings (OSTI)

Table 4 Applications of permanent magnet materials...material Primary reason for selection Alternative material Condition or reason favoring selection of alternative material Aircraft magnetos, military or civilian SmCo Maximum energy per unit volume Cast Alnico 5 Availability or cost restraint Alternators SmCo Compactness and reliability Ferrite...

113

220,000-r/min, 2-kW Permanent Magnet Motor Drive for Turbocharger Toshihiko Noguchi, Yosuke Takata *  

E-Print Network (OSTI)

220,000-r/min, 2-kW Permanent Magnet Motor Drive for Turbocharger Toshihiko Noguchi, Yosuke Takata-speed permanent-magnet synchronous motor drive, which is embedded in a turbocharger of an internal permanent magnet. Also, it is indispensable to reduce the motor inductance less than 10 (µH) because dc bus

Fujimoto, Hiroshi

114

Abstract--This paper presents an analysis by which the dynamic performances of a permanent magnet synchronous  

E-Print Network (OSTI)

; Permanent magnet synchronous motor; Speed control; Fuzzy; Sliding Mode. I. INTRODUCTION As a resultAbstract-- This paper presents an analysis by which the dynamic performances of a permanent magnet synchronous motor (PMSM) motor is controlled through a hysteresis current loop and an outer speed loop

Paris-Sud XI, Université de

115

Permanent split capacitor single phase electric motor system  

DOE Patents (OSTI)

A permanent split capacitor single phase electric motor achieves balanced operation at more than one operating point by adjusting the voltage supplied to the main and auxiliary windings and adjusting the capacitance in the auxiliary winding circuit. An intermediate voltage tap on an autotransformer supplies voltage to the main winding for low speed operation while a capacitive voltage divider is used to adjust the voltage supplied to the auxiliary winding for low speed operation. 4 figs.

Kirschbaum, H.S.

1984-08-14T23:59:59.000Z

116

Performance improvement of permanent magnet ac motors  

E-Print Network (OSTI)

Multi-phase motors have several advantages over the traditional three-phase motors. In this study, the additional degrees of freedom available in five-phase permanent magnet motors have been used for three purposes: 1) enhancing the torque producing capability of the motor, 2) improving the reliability of the system, and 3) better adjusting of the torque and flux linkages of the five-phase direct torque controlled system. 1) Due to the fact that space and time harmonics of the same orders will contribute positively to output torque, a five-phase permanent magnet motor with quasi-rectangular back-EMF waveform is supplied with combined fundamental and third harmonic of currents. For modeling and analysis of the motor a 0 3 3 1 1 q d q d frame of reference is defined where 1 1q d rotates at the synchronous speed and 3 3q d rotates at the three times synchronous speed. Based on the mathematical model in the 0 3 3 1 1 q d q d frame of reference, it is shown that this system while having a higher torque density with respect to a conventional permanent magnet synchronous machine, is also compatible with vector control algorithm. 2) A resilient current control of the five-phase permanent motor with both sinusoidal and trapezoidal back-EMF waveforms under asymmetrical fault condition is proposed. In this scheme, the stator MMF is kept unchanged during healthy and faulty condition. Therefore, the five-phase permanent magnet motor operates continuously and steadily without additional hardware and just by modifying the control algorithm in case of loss of up to two phases. The feature is of major importance in some specific applications where high reliability is required. 3) High torque and flux ripple are the major drawbacks of a three-phase direct torque controlled system. The number of space voltage vectors directly influences the performance of DTC system. A five-phase drive, while benefiting from other advantages of high order phase drives, has inherently 32 space voltage vectors which permits better flexibility in selecting the switching states and finer adjustment of flux and torque. A sensorless direct torque control of five-phase permanent magnet motor is implemented. Speed information is obtained based on the position of stator flux linkages and load angle. Experiments have been conducted on a 5kW five-phase surface mount permanent magnet motor and a 3kW five-phase interior permanent magnet motor by using TMS320C32 DSP. The results obtained are consistent with theoretical studies and simulation analysis, which further demonstrate the feasibility and practical significance of the five-phase permanent magnet motor drives.

Parsa, Leila

2005-05-01T23:59:59.000Z

117

Textured Polycrystalline Permanent Magnet Nanoflakes  

Science Conference Proceedings (OSTI)

... high electrical resistivity, which will reduce eddy current losses and improve motor efficiency. ... Combinatorial Search of Rare-Earth-Free Permanent Magnets

118

Permanent Magnets for Energy Applications  

Science Conference Proceedings (OSTI)

Mar 13, 2012 ... Magnetic Materials for Energy Applications II: Permanent Magnets for ... to 500% in the last 12 months, the most unstable being the price of Dy.

119

Table 1. Design specifications of ultra-high speed PM motor. Supply voltage (V) 12  

E-Print Network (OSTI)

Analysis of Ultra-High Speed Permanent-Magnet Motor Masaru Kano, and Toshihiko Noguchi Department@vos.nagaokaut.ac.jp Abstract This paper describes a design of an ultra-high speed (UHS) permanent-magnet (PM) synchronous motor, a surface permanent-magnet (SPM) motor (150,000 r/min, 1.5 kW) fed by a low voltage battery (12 V

Fujimoto, Hiroshi

120

Axial-flux modular permanent-magnet generator with a toroidal winding for wind-turbine applications  

SciTech Connect

Permanent-magnet (PM) generators have been used for wind turbines for many years. Many small wind-turbine manufacturers use direct-drive PM generators. For wind-turbine generators, the design philosophy must cover the following characteristics: low cost, light weight, low speed, high torque, and variable-speed generation. The generator is easy to manufacture and the design can be scaled up for a larger size without major retooling. A modular PM generator with axial flux direction was chosen. The permanent magnet used is NdFeB or ferrite magnet with flux guide to focus flux density in the air gap. Each unit module of the generator may consist of one, two, or more phases. Each generator can be expanded to two or more unit modules. Each unit module is built from simple modular poles. The stator winding is formed like a torus. Thus, the assembly process is simplified and the winding insertion in the slot is less tedious. The authors built a prototype of one unit module and performed preliminary tests in the laboratory. Follow-up tests will be conducted in the laboratory to improve the design.

Muljadi, E.; Butterfield, C.P.; Wan, Y.H.

1999-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "variable speed permanent" 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

Permanent Load Shift Control Strategies  

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

of Permanent Load Shifting for HVAC and other storage assets as it relates to summer on-peak demand, how it can be dynamically and autonomously controlled, and its relationship...

122

Operational behavior of a double-fed permanent magnet generator for wind turbines  

E-Print Network (OSTI)

Greater efficiency in wind turbine systems is achieved by allowing the rotor to change its rate of rotation as the wind speed changes. The wind turbine system is decoupled from the utility grid and a variable speed operation ...

Reddy, Sivananda Kumjula

2005-01-01T23:59:59.000Z

123

Magnetically Coupled Adjustable Speed Drive Systems  

DOE Green Energy (OSTI)

Adjustable speed drive (ASD) technologies have the ability to precisely control motor sytems output and produce a numbr of benefits including energy and demand savings. This report examines the performance and cost effectiveness of a specific class of ASDs called magnetically-coupled adjustable speed drives (MC-ASD) which use the strength of a magnetic field to control the amount of torque transferred between motor and drive shaft. The MagnaDrive Adjustable Speed Coupling System uses fixed rare-earth magnets and varies the distance between rotating plates in the assembly. the PAYBACK Variable Speed Drive uses an electromagnet to control the speed of the drive

Chvala, William D.; Winiarski, David W.

2002-08-18T23:59:59.000Z

124

Dual-speed wind turbine generation  

SciTech Connect

Induction generator has been used since the early development of utility-scale wind turbine generation. An induction generator is the generator of choice because of its ruggedness and low cost. With an induction generator, the operating speed of the wind turbine is limited to a narrow range (almost constant speed). Dual- speed operation can be accomplished by using an induction generator with two different sets of winding configurations or by using a dual output drive train to drive two induction generators with two different rated speeds. With single-speed operation, the wind turbine operates at different power coefficients (Cp) as the wind speed varies. Operation at maximum Cp can occur only at a single wind speed. However, if the wind speed.varies across a wider range, the operating Cp will vary significantly. Dual-speed operation has the advantage of enabling the wind turbine to operate at near maximum Cp over a wider range of wind speeds. Thus, annual energy production can be increased. The dual-speed mode may generate less energy than a variable-speed mode; nevertheless, it offers an alternative which captures more energy than single-speed operation. In this paper, dual-speed operation of a wind turbine is investigated. Annual energy production is compared between single-speed and dual-speed operation. One type of control algorithm for dual-speed operation is proposed. Some results from a dynamic simulation will be presented to show how the control algorithm works as the wind turbine is exposed to varying wind speeds.

Muljadi, E.; Butterfield, C.P. [National Renewable Energy Lab., Golden, CO (United States); Handman, D. [Flowind Corp., San Rafael, CA (United States)

1996-10-01T23:59:59.000Z

125

ARE660 Wind Generator: Low Wind Speed Technology for Small Turbine Development  

DOE Green Energy (OSTI)

This project is for the design of a wind turbine that can generate most or all of the net energy required for homes and small businesses in moderately windy areas. The purpose is to expand the current market for residential wind generators by providing cost effective power in a lower wind regime than current technology has made available, as well as reduce noise and improve reliability and safety. Robert W. Preus’ experience designing and/or maintaining residential wind generators of many configurations helped identify the need for an improved experience of safety for the consumer. Current small wind products have unreliable or no method of stopping the wind generator in fault or high wind conditions. Consumers and their neighbors do not want to hear their wind generators. In addition, with current technology, only sites with unusually high wind speeds provide payback times that are acceptable for the on-grid user. Abundant Renewable Energy’s (ARE) basic original concept for the ARE660 was a combination of a stall controlled variable speed small wind generator and automatic fail safe furling for shutdown. The stall control for a small wind generator is not novel, but has not been developed for a variable speed application with a permanent magnet alternator (PMA). The fail safe furling approach for shutdown has not been used to our knowledge.

Robert W. Preus; DOE Project Officer - Keith Bennett

2008-04-23T23:59:59.000Z

126

Multi-winding Homopolar Electric Machine Offers Variable ...  

The device can be used as either a motor or a generator. Advantages • Variable voltage and speed design • Internal mechanism allowing for low speed, high

127

Adjustable Speed Drive Industrial Applications  

E-Print Network (OSTI)

Electric motors are significant users of electricity in the United States. Approximately 66 percent of the total electricity in the U.S. is used by electric motors. Electronic adjustable speed drives (ASDs) can save energy, lower maintenance cost and improve product quality. By providing a variable frequency output to ac motors the speed of the motors can be controlled and matched to the process requirements. The benefits that may be derived from using ASDs are described and the type of ASDs, applications and specific case studies of ASD installations are also discussed.

Poole, J. N.

1989-09-01T23:59:59.000Z

128

Synchronous Motor Observability Study and an Improved Zero-speed Position Estimation Design  

E-Print Network (OSTI)

with the Permanent Magnet Synchronous Motor (PMSM) observability analysis for sensor- less control design here for the surface Permanent Magnet Synchronous Motor (PMSM) to overcome position observabilitySynchronous Motor Observability Study and an Improved Zero-speed Position Estimation Design Dalila

Paris-Sud XI, Université de

129

Extreme learning machine based wind speed estimation and sensorless control for wind turbine power generation system  

Science Conference Proceedings (OSTI)

This paper proposes a precise real-time wind speed estimation method and sensorless control for variable-speed variable-pitch wind turbine power generation system (WTPGS). The wind speed estimation is realized by a nonlinear input-output mapping extreme ... Keywords: Extreme learning machine, Sensorless control, Wind speed estimation, Wind turbine power generation system

Si Wu; Youyi Wang; Shijie Cheng

2013-02-01T23:59:59.000Z

130

DSP-Based Sensor-less Permanent Magnet Synchronous Motor Driver With Quasi-Sine PWM for Air-Conditioner Rotary Compressor.  

E-Print Network (OSTI)

??This thesis presented a sensor-less permanent magnet synchronous motor (PMSM) driver for controlling air-conditioner rotary compressor speed. In this thesis, a quasi-sine pulse-width modulation (PWM)… (more)

Liu, Li-hsiang

2012-01-01T23:59:59.000Z

131

Performance Variability  

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

Variability Variability of Highly Parallel Architectures William T.C. Kramer 1 and Clint Ryan 2 1 Department of Computing Sciences, University of California at Berkeley and the National Energy Research Scientific Computing Center, Lawrence Berkeley National Laboratory 2 Department of Computing Sciences, University of California at Berkeley Abstract. The design and evaluation of high performance computers has concentrated on increasing computational speed for applications. This performance is often measured on a well configured dedicated sys- tem to show the best case. In the real environment, resources are not always dedicated to a single task, and systems run tasks that may influ- ence each other, so run times vary, sometimes to an unreasonably large extent. This paper explores the amount of variation seen across four large distributed memory systems in a systematic manner. It then

132

Can Satellite Sampling of Offshore Wind Speeds Realistically Represent Wind Speed Distributions?  

Science Conference Proceedings (OSTI)

Wind speeds over the oceans are required for a range of applications but are difficult to obtain through in situ methods. Hence, remote sensing tools, which also offer the possibility of describing spatial variability, represent an attractive ...

R. J. Barthelmie; S. C. Pryor

2003-01-01T23:59:59.000Z

133

High Temperature, Buried Permanent Magnet, Brushless DC Motor  

E-Print Network (OSTI)

A high temperature magnetic bearing system using high temperature permanent magnets from Electron Energy Corporation (EEC) is under development. The system consists of two radial bearings, one thrust bearing, two radial catcher bearings and one motor. The purpose of this research is to develop one of the critical components of the system, namely, the High Temperature Permanent Magnet motor. A novel High Temperature Permanent Magnet (HTPM) Brushless DC(BLDC) motor capable of operating at 1000 degrees F (538 degrees C) is designed. HTPMs developed at Electron Energy Corporation are buried into the rotor. The high temperature motor is designed to produce 5.1kw of power at a top running speed of 20000 rpm. The numerical values of the motor voltage, power and torque output are predicted from calculations of the nonlinear finite element model of the motor. The motor stator is wound, potted, cured and high potential tested at 1000 degrees F. A servo amplifier from Advanced Motion Control is used to drive the high temperature motor. High temperature displacement sensors are set up for sensing the rotor position to form a closed loop motion control. However, the noise problem of the high temperature sensors causes a failure of this approach. An open loop approach is then developed and this approach succeeds in spinning the rotor with the capability of self-starting. The status of the full system assembling is introduced. Some other components of the system are briefly presented.

Zhang, Zhengxin

2010-08-01T23:59:59.000Z

134

Control system for an interior permanent magnet synchronous machine  

DOE Patents (OSTI)

A high performance, fully operational, four-quadrant control scheme is used in an interior permanent magnet synchronous machine. The machine operates smoothly with full performance in the constant-torque region as well as in the flux-weakening, constant-power region in both directions of motion. The transition between the constant-torque and constant-power regions is very smooth under all conditions of operation. Control in the constant-torque region is based on a vector or field-oriented technique, with the direct-axis aligned with the total stator flux, whereas constant-power region control is accomplished by orientation of the torque angle of the impressed square-wave voltage through the feedforward vector rotator. In a preferred embodiment, the control system employs a digital distributed microcomputer controller arrangement which relies upon various precisely estimated feedback signals, such as torque, flux, etc. The control scheme includes an outer torque control loop primarily for traction type applications, but also contemplates speed and position control loops for various industrial drives. A 70 hp drive system using a Neodymium-Iron-Boron permanent magnet machine and transistor pulse width modulating inverter has been designed and successfully tested. This control scheme also has application in controlling surface permanent magnet machines. 16 figs.

Bose, B.K.

1988-10-12T23:59:59.000Z

135

Dynamic simulation of dual-speed wind turbine generation  

SciTech Connect

Induction generators have been used since the early development of utility-scale wind turbine generation. An induction generator is the generator of choice because of its ruggedness, and low cost. With an induction generator, the operating speed of the wind turbine is limited to a narrow range (almost constant speed). Dual- speed operation can be accomplished by using an induction generator with two different sets of winding configurations or by using two induction generators with two different rated speeds. With single- speed operation, the wind turbine operates at different power coefficients (Cp) as the wind speed varies. The operation at maximum Cp can occur only at a single wind speed. However, if the wind speed varies across a wider range, the operating Cp will vary significantly. Dual-speed operation has the advantage of enabling the wind turbine to operate at near maximum Cp over a wider range of wind-speeds. Thus, annual energy production can be increased. The dual-speed mode may generate less energy than a variable-speed mode; nevertheless, it offers an alternative to capture more energy than single-speed operation. In this paper, dual-speed operation of a wind turbine will be investigated. One type of control algorithm for dual- speed operation is proposed. Results from a dynamic simulation will be presented to show how the control algorithm works and how power, current and torque of the system vary as the wind turbine is exposed to varying wind speeds.

Muljadi, E.; Butterfield, C.P.

1996-10-01T23:59:59.000Z

136

Magnetic Microstructures of Novel High Performance Permanent ...  

Science Conference Proceedings (OSTI)

... Nd-Fe-B Permanent Magnets · Unique Exchange Bias Induced by Antiferromagnetic Cr-oxide · ZnO-graphene Hybrid Quantum Dots Light Emitting Diode ...

137

High Speed Electronics  

Science Conference Proceedings (OSTI)

High Speed Electronics. ... optic sampling system provides traceability for our electrical waveform measurements ... Metrology for Electronic Packaging. ...

2013-03-25T23:59:59.000Z

138

Extreme Wind Speeds: Publications  

Science Conference Proceedings (OSTI)

... "Algorithms for Generating Large Sets of Synthetic Directional Wind Speed Data for Hurricane, Thunderstorm, and Synoptic Winds," NIST Technical ...

2013-08-19T23:59:59.000Z

139

Speed control system for an access gate  

DOE Patents (OSTI)

An access control apparatus for an access gate. The access gate typically has a rotator that is configured to rotate around a rotator axis at a first variable speed in a forward direction. The access control apparatus may include a transmission that typically has an input element that is operatively connected to the rotator. The input element is generally configured to rotate at an input speed that is proportional to the first variable speed. The transmission typically also has an output element that has an output speed that is higher than the input speed. The input element and the output element may rotate around a common transmission axis. A retardation mechanism may be employed. The retardation mechanism is typically configured to rotate around a retardation mechanism axis. Generally the retardation mechanism is operatively connected to the output element of the transmission and is configured to retard motion of the access gate in the forward direction when the first variable speed is above a control-limit speed. In many embodiments the transmission axis and the retardation mechanism axis are substantially co-axial. Some embodiments include a freewheel/catch mechanism that has an input connection that is operatively connected to the rotator. The input connection may be configured to engage an output connection when the rotator is rotated at the first variable speed in a forward direction and configured for substantially unrestricted rotation when the rotator is rotated in a reverse direction opposite the forward direction. The input element of the transmission is typically operatively connected to the output connection of the freewheel/catch mechanism.

Bzorgi, Fariborz M. (Knoxville, TN)

2012-03-20T23:59:59.000Z

140

A Novel Current Angle Control Scheme in a Current Source Inverter Fed Permanent Magnet Synchronous Motor Drive for Automotive Applications  

DOE Green Energy (OSTI)

This paper describes a novel speed control scheme to operate a current source inverter (CSI) driven surface-mounted permanent magnet synchronous machine (SPMSM) for hybrid electric vehicles (HEVs) applications. The idea is to use the angle of the current vector to regulate the rotor speed while keeping the two dc-dc converter power switches on all the time to boost system efficiency. The effectiveness of the proposed scheme was verified with a 3 kW CSI-SPMSM drive prototype.

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

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "variable speed permanent" 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

Development of Wind Speed Forecasting Model Based on the Weibull Probability Distribution  

Science Conference Proceedings (OSTI)

Wind is a variable energy source. The power output of a wind turbine generator (WTG) unit, therefore, fluctuates with wind speed variations. Accurate models reflecting the variability of wind speed is hence required in both reliability evaluation of ... Keywords: Wind Energy, Wind Speed Forecasting Model, Weibull Distribution, Maximum Likelihood Method, Time Series Model

Ruigang Wang; Wenyi Li; B. Bagen

2011-02-01T23:59:59.000Z

142

Drill Press Speed Chart  

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

operating speeds (RPM) Accessory Softwood (Pine) Hardwood (Hard Maple) Acrylic Brass Aluminum Steel Shop Notes Twist drill bits 116" - 316" 14" - 38" 716"- 58" 11...

143

Transient Peak Currents in Permanent Magnet Synchronous Motors  

E-Print Network (OSTI)

Transient Peak Currents in Permanent Magnet Synchronous Motors for Symmetrical Short Circuits Terms-- Permanent magnet synchronous motor, short circuit, protection measure, transient behavior I 33095 Paderborn, Germany Abstract--To enable constant-power areas with permanent magnet synchronous

Noé, Reinhold

144

Hybrid Electric Vehicle with Permanent Magnet Traction Motor: A Simulation Model  

E-Print Network (OSTI)

A simulation model for a hybrid electric vehicle is developed. Permanent magnet synchronous motor is considered for the drive part of the hybrid electric vehicle which comprises three energy sources: (i) a fuel cell, (ii) a battery bank, and (iii) a super capacitor. Rotor-oriented speed controller is designed, and also verified by simulation results, to achieve trajectory tracking requirements of the hybrid electric vehicle within the inverter voltage and current limits.

Levent U. Gökdere; Khalid Benlyazid; Enrico; Enrico Santi; Charles W. Brice; Roger A. Dougal

1999-01-01T23:59:59.000Z

145

Permanent magnet hydrogen oxygen generating cells  

SciTech Connect

A generating cell for hydrogen and oxygen utilizes permanent magnets and electromagnets. Means are provided for removing gases from the electrodes. Mixing chambers are provided for water and the electrolyte used in the cell.

Harris, M.

1976-07-13T23:59:59.000Z

146

Modeling and optimization of permanent magnetic motors  

E-Print Network (OSTI)

This thesis develops analytic models for the prediction and optimization of radial-flux permanent magnet motor torque and efficiency. It also facilitates the design optimization of electromagnetically-powered rotorcraft ...

Pinkham, Andrew P

2008-01-01T23:59:59.000Z

147

The rope memory: a permanent storage device  

Science Conference Proceedings (OSTI)

A powerful way of increasing the capability and flexibility of digital computing systems is through the use of permanent storage memories. Such memories are also known as readonly memories or NDRO electrically unalterable memories. As an example of the ...

P. Kuttner

1963-11-01T23:59:59.000Z

148

Hybrid-secondary uncluttered permanent magnet machine and ...  

An electric machine (40) has a stator (43), a permanent magnet rotor (38) with permanent magnets (39) and a magnetic coupling uncluttered rotor (46) for inducing a ...

149

Permanent magnet edge-field quadrupole  

DOE Patents (OSTI)

Planar permanent magnet edge-field quadrupoles for use in particle accelerating machines and in insertion devices designed to generate spontaneous or coherent radiation from moving charged particles are disclosed. The invention comprises four magnetized rectangular pieces of permanent magnet material with substantially similar dimensions arranged into two planar arrays situated to generate a field with a substantially dominant quadrupole component in regions close to the device axis.

Tatchyn, Roman O. (Mountain View, CA)

1997-01-01T23:59:59.000Z

150

California high speed rail proposal: “High speed rail and wildlife”  

E-Print Network (OSTI)

Wildlife and High Speed Rail C ALIFORNIA H IGH S PEED R AILLeavitt, California High Speed Rail Authority) Abstract TheCalifornia High Speed Rail (HSR) Proposal is in the initial

Wilkerson, Cynthia

2005-01-01T23:59:59.000Z

151

Full Hybrid: Low Speed  

Alternative Fuels and Advanced Vehicles Data Center (EERE)

highlighted Cruising button Passing button Braking button Stopped button highlighted Cruising button Passing button Braking button Stopped button LOW SPEED For initial acceleration and slow-speed driving, as well as reverse, the electric motor uses electricity from the battery to power the vehicle. If the battery needs to be recharged, the generator starts the engine and converts energy from the engine into electricity, which is stored in the battery. stage graphic: vertical blue rule Main stage: See through car with battery, engine, generator, power split device, and electric motor visible. The car is moving at a low speed. There are arrows flowing from the battery to the electric motor to the power split device to the front wheels. Main stage: See through car with battery, engine, generator, power split device, and electric motor visible. The car is moving at a low speed. There are arrows flowing from the battery to the electric motor to the power split device to the front wheels.

152

High-Speed Biomass Recalcitrance Pipeline Speeds Up Bio ...  

High-Speed Biomass Recalcitrance Pipeline Speeds Up Bio-Mass Analysis Robotic pipeline allows for rapid analysis of optimal substrate/enzyme ...

153

economic means to permanently store CO  

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

economic means to permanently store CO economic means to permanently store CO 2 in unmineable coal seams. Prior to the injection, horizontal coalbed methane (CBM) wells were drilled approximately 1,200 to 1,800 feet underground in a five-spot pattern over a 200-acre area in the unmineable Upper Freeport coal seam. As part of this $13 million field trial, which is being conducted under the collaboration of the National Energy Technology Laboratory (NETL), West Virginia University, and CONSOL Energy, Inc., CO 2 will be injected at a pressure of up to 700 pounds per square inch (psi)

154

FE Magnetic Field Analysis Simulation Models based Design, Development, Control and Testing of An Axial Flux Permanent Magnet Linear Oscillating Motor  

E-Print Network (OSTI)

Abstract- Development, finite element(FE) analysis of magnetic field distribution, performance, control and testing of a new axial flux permanent magnet linear oscillating motor (PMLOM) along with a suitable speed and thrust control technique is described in this paper. The PMLOM can perform precision oscillation task without exceeding the given limit on allowable average power dissipation. The use of new powerful permanent magnet materials such as Neodymium-Iron-Boron alloys can greatly improve the performance of electrical machines. Also its performance parameters, such as the force, current etc. are experimentally assessed. The objective of this paper is to determine the forces for aluminium mover embedded with rare earth permanent magnet experimentally and analytically through FEMM software and develop a microcontroller based IGBT Inverter for its control. Index Terms- Axial flux machine, finite element analysis, microcontroller based IGBT inverter, permanent magnet linear oscillating motor, rare earth permanent magnet. I.

Govindaraj T; Prof Dr; Ashoke K. Ganguli

2009-01-01T23:59:59.000Z

155

High speed flywheel  

DOE Patents (OSTI)

This invention relates generally to flywheels and relates more particularly to the construction of a high speed, low-mass flywheel. Flywheels with which this invention is to be compared include those constructed of circumferentially wound filaments or fibers held together by a matrix or bonding material. Flywheels of such construction are known to possess a relatively high hoop strength but a relatively low radial strength. Hoop-wound flywheels are, therefore, particularly susceptible to circumferential cracks, and the radial stress limitations of such a flywheel substantially limit its speed capabilities. It is an object of the present invention to provide a new and improved flywheel which experiences reduced radial stress at high operating speeds. Another object of the present invention is to provide flywheel whose construction allows for radial growth as flywheel speed increases while providing the necessary stiffness for transferring and maintaining kinetic energy within the flywheel. Still another object of the present invention is to provide a flywheel having concentrically-disposed component parts wherein rotation induced radial stresses at the interfaces of such component parts approach zero. Yet another object of the present invention is to provide a flywheel which is particularly well-suited for high speed applications. 5 figs.

McGrath, S.V.

1990-01-01T23:59:59.000Z

156

Dovetail spoke internal permanent magnet machine  

Science Conference Proceedings (OSTI)

An internal permanent magnet (IPM) machine is provided. The IPM machine includes a stator assembly and a stator core. The stator core also includes multiple stator teeth. The stator assembly is further configured with stator windings to generate a stator magnetic field when excited with alternating currents and extends along a longitudinal axis with an inner surface defining a cavity. The IPM machine also includes a rotor assembly and a rotor core. The rotor core is disposed inside the cavity and configured to rotate about the longitudinal axis. The rotor assembly further includes a shaft. The shaft further includes multiple protrusions alternately arranged relative to multiple bottom structures provided on the shaft. The rotor assembly also includes multiple stacks of laminations disposed on the protrusions and dovetailed circumferentially around the shaft. The rotor assembly further includes multiple pair of permanent magnets for generating a magnetic field, which magnetic field interacts with the stator magnetic field to produce a torque. The multiple pair of permanent magnets are disposed between the stacks. The rotor assembly also includes multiple middle wedges mounted between each pair of the multiple permanent magnets.

Alexander, James Pellegrino (Ballston Lake, NY); EL-Refaie, Ayman Mohamed Fawzi (Niskayuna, NY); Lokhandwalla, Murtuza (Clifton Park, NY); Shah, Manoj Ramprasad (Latham, NY); VanDam, Jeremy Daniel (West Coxsackie, NY)

2011-08-23T23:59:59.000Z

157

When Do Commercial Reactors Permanently Shut Down?  

Reports and Publications (EIA)

For those wishing to obtain current data, the following resources are available: U.S. reactors, go to EIA's nuclear reactor shutdown list. (Note: As of April 30, 2010, the last U.S. reactor to permanently shut down was Big Rock Point in 1997.) Foreign Reactors, go to the Power Reactor Information System (PRIS) on the International Atomic Energy Agency's website.

Information Center

2011-05-10T23:59:59.000Z

158

High-Speed Permanent-Magnet Motors for the Oil&Gas ...  

Science Conference Proceedings (OSTI)

... Enable tight integration of drive motor with compressor ... raw / wet gas design ... Tighter integration of compressor, motor and drive components and ...

2012-10-14T23:59:59.000Z

159

NEW OPTIMAL HIGH EFFICIENCY DSP-BASED DIGITAL CONTROLLER DESIGN FOR SUPER HIGH-SPEED PERMANENT  

E-Print Network (OSTI)

MAGNET SYNCHRONOUS MOTOR by LIMEI ZHAO A dissertation submitted in partial fulfillment magnet synchronous motors (PMSM). The PMSMs are a key component for the miniaturic cryocooler and the Florida Solar Energy Center. Advanced motor design methods, control strategies, and rapid progress

Wu, Shin-Tson

160

Permanent isolation surface barrier development plan  

Science Conference Proceedings (OSTI)

The exhumation and treatment of wastes may not always be the preferred alternative in the remediation of a waste site. In-place disposal alternatives, under certain circumstances, may be the most desirable alternatives to use in the protection of human health and the environment. The implementation of an in-place disposal alternative will likely require some type of protective covering that will provide long-term isolation of the wastes from the accessible environment. Even if the wastes are exhumed and treated, a long-term barrier may still be needed to adequately dispose of the treated wastes or any remaining waste residuals. Currently, no {open_quotes}proven{close_quotes} long-term barrier is available. The Hanford Site Permanent Isolation Surface Barrier Development Program (BDP) was organized to develop the technology needed to provide a long-term surface barrier capability for the Hanford Site. The permanent isolation barrier technology also could be used at other sites. Permanent isolation barriers use engineered layers of natural materials to create an integrated structure with redundant protective features. Drawings of conceptual permanent isolation surface barriers are shown. The natural construction materials (e.g., fine soil, sand, gravel, riprap, asphalt) have been selected to optimize barrier performance and longevity. The objective of current designs is to use natural materials to develop a maintenance-free permanent isolation surface barrier that isolates wastes for a minimum of 1,000 years by limiting water drainage to near-zero amounts; reducing the likelihood of plant, animal, and human intrusion; controlling the exhalation of noxious gases; and minimizing erosion-related problems.

Wing, N.R.

1994-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "variable speed permanent" 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

Variable percentage sampler  

DOE Patents (OSTI)

A remotely operable sampler is provided for obtaining variable percentage samples of nuclear fuel particles and the like for analyses. The sampler has a rotating cup for a sample collection chamber designed so that the effective size of the sample inlet opening to the cup varies with rotational speed. Samples of a desired size are withdrawn from a flowing stream of particles without a deterrent to the flow of remaining particles.

Miller, Jr., William H. (Knoxville, TN)

1976-01-01T23:59:59.000Z

162

DOE Guidance - Permanent and Nonpermanent Positions, Appointments, &  

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

Guidance - Permanent and Nonpermanent Positions, Guidance - Permanent and Nonpermanent Positions, Appointments, & CHRIS Codes DOE Guidance - Permanent and Nonpermanent Positions, Appointments, & CHRIS Codes Guidance Memorandum #23 DOE Guidance - Permanent and Nonpermanent Positions, Appointments, & CHRIS Codes This document provides assistance in determining whether a new position should be designated as permanent or nonpermanent (temporary), to provide examples of the various types of appointments and personnel actions that can be used with position determinations, and to define the associated Corporate Human Resource Information System (CHRIS) position codes. Permanent and Nonpermanent Positions, Appointments, & CHRIS Codes Responsible Contacts Bruce Murray HR Policy Advisor E-mail bruce.murray@hq.doe.gov

163

DOE Guidance - Permanent and Nonpermanent Positions, Appointments, &  

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

Guidance - Permanent and Nonpermanent Positions, Guidance - Permanent and Nonpermanent Positions, Appointments, & CHRIS Codes DOE Guidance - Permanent and Nonpermanent Positions, Appointments, & CHRIS Codes Guidance Memorandum #23 DOE Guidance - Permanent and Nonpermanent Positions, Appointments, & CHRIS Codes This document provides assistance in determining whether a new position should be designated as permanent or nonpermanent (temporary), to provide examples of the various types of appointments and personnel actions that can be used with position determinations, and to define the associated Corporate Human Resource Information System (CHRIS) position codes. Permanent and Nonpermanent Positions, Appointments, & CHRIS Codes Responsible Contacts Bruce Murray HR Policy Advisor E-mail bruce.murray@hq.doe.gov

164

Medium-Speed Drivetrain Test Report: September 1, 2002 -- December 30, 2007  

DOE Green Energy (OSTI)

This report describes the tests conducted by researchers at the National Wind Technology Center at NREL on a 1.5-MW integrated drivetrain consisting of a single-stage, epicyclic gearbox and close-coupled medium-speed permanent-magnet generator.

Walford, C.; Lybarger, K.; Lettenmaier, T.; Roberts, D.

2012-09-01T23:59:59.000Z

165

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

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

166

Electro-mechanical energy conversion system having a permanent ...  

Electro-mechanical energy conversion system having a permanent magnet machine with stator, resonant transfer link and energy converter controls

167

Forecasting Solar Wind Speeds  

E-Print Network (OSTI)

By explicitly taking into account effects of Alfven waves, I derive from a simple energetics argument a fundamental relation which predicts solar wind (SW) speeds in the vicinity of the earth from physical properties on the sun. Kojima et al. recently found from their observations that a ratio of surface magnetic field strength to an expansion factor of open magnetic flux tubes is a good indicator of the SW speed. I show by using the derived relation that this nice correlation is an evidence of the Alfven wave which accelerates SW in expanding flux tubes. The observations further require that fluctuation amplitudes of magnetic field lines at the surface should be almost universal in different coronal holes, which needs to be tested by future observations.

Takeru K. Suzuki

2006-02-03T23:59:59.000Z

168

High speed door assembly  

DOE Patents (OSTI)

This invention is comprised of a high speed door assembly, comprising an actuator cylinder and piston rods, a pressure supply cylinder and fittings, an electrically detonated explosive bolt, a honeycomb structured door, a honeycomb structured decelerator, and a structural steel frame encasing the assembly to close over a 3 foot diameter opening within 50 milliseconds of actuation, to contain hazardous materials and vapors within a test fixture.

Shapiro, C.

1991-12-31T23:59:59.000Z

169

Two-speed transaxle  

DOE Patents (OSTI)

Disclosed is a drive assembly (10) for an electrically powered vehicle (12). The assembly includes a transaxle (16) having a two-speed transmission (40) and a drive axle differential (46) disposed in a unitary housing assembly (38), an oil-cooled prime mover or electric motor (14) for driving the transmission input shaft (42), an adapter assembly (24) for supporting the prime mover on the transaxle housing assembly, and a hydraulic system (172) providing pressurized oil flow for cooling and lubricating the electric motor and transaxle and for operating a clutch (84) and a brake (86) in the transmission to shift between the two-speed ratios of the transmission. The adapter assembly allows the prime mover to be supported in several positions on the transaxle housing. The brake is spring-applied and locks the transmission in its low-speed ratio should the hydraulic system fail. The hydraulic system pump is driven by an electric motor (212) independent of the prime mover and transaxle.

Kalns, Ilmars (Northville, MI)

1981-01-01T23:59:59.000Z

170

Evaluation of performance and magnetic characteristics of a radial-radial flux compound-structure permanent-magnet synchronous machine used for hybrid electric vehicle  

Science Conference Proceedings (OSTI)

A breed of compound-structure permanent-magnet synchronous machine (CS-PMSM) is used for power-split hybrid electric vehicles(HEVs). It can help to fulfill both the speed and torque control of the internal combustion engine and

Ping Zheng; Ranran Liu; Lin Shen; Lina Li; Weiguang Fan; Qian Wu; Jing Zhao

2008-01-01T23:59:59.000Z

171

Jiangxi Jinli Permanent Magnet Technology Co Ltd | Open Energy Information  

Open Energy Info (EERE)

Jinli Permanent Magnet Technology Co Ltd Jinli Permanent Magnet Technology Co Ltd Jump to: navigation, search Name Jiangxi Jinli Permanent Magnet Technology Co Ltd Place Ganzhou, Jiangxi Province, China Sector Wind energy Product A China-based mining company for rare earth metals used in wind power generators. References Jiangxi Jinli Permanent Magnet Technology Co Ltd[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. Jiangxi Jinli Permanent Magnet Technology Co Ltd is a company located in Ganzhou, Jiangxi Province, China . References ↑ "Jiangxi Jinli Permanent Magnet Technology Co Ltd" Retrieved from "http://en.openei.org/w/index.php?title=Jiangxi_Jinli_Permanent_Magnet_Technology_Co_Ltd&oldid=347439

172

Effect of Side Permanent Magnets for Reluctance Interior Permanent Magnet Reluctance Machines  

Science Conference Proceedings (OSTI)

A traditional electric machine uses two dimensional magnetic flux paths in its rotor. This paper presents the development work on the utilization of the third dimension of a rotor. As an example, the air gap flux of a radial gap interior permanent magnet motor can be significantly enhanced by additional permanent magnets (PM) mounted at the sides of the rotor. A prototype motor built with this concept provided higher efficiency and required a shorter stator core length for the same power output as the Toyota/Prius traction drive motor.

Hsu, John S [ORNL; Lee, Seong T [ORNL; Wiles, Randy H [ORNL; Coomer, Chester [ORNL; Lowe, Kirk T [ORNL

2007-01-01T23:59:59.000Z

173

Variable-Period Undulators for Synchrotron Radiation  

DOE Patents (OSTI)

A new and improved undulator design is provided that enables a variable period length for the production of synchrotron radiation from both medium-energy and high energy storage rings. The variable period length is achieved using a staggered array of pole pieces made up of high permeability material, permanent magnet material, or an electromagnetic structure. The pole pieces are separated by a variable width space. The sum of the variable width space and the pole width would therefore define the period of the undulator. Features and advantages of the invention include broad photon energy tunability, constant power operation and constant brilliance operation.

Shenoy, Gopal; Lewellen, John; Shu, Deming; Vinokurov, Nikolai

2005-02-22T23:59:59.000Z

174

Batch fabrication of precision miniature permanent magnets  

DOE Patents (OSTI)

A new class of processes for fabrication of precision miniature rare earth permanent magnets is disclosed. Such magnets typically have sizes in the range 0.1 to 10 millimeters, and dimensional tolerances as small as one micron. Very large magnetic fields can be produced by such magnets, lending to their potential application in MEMS and related electromechanical applications, and in miniature millimeter-wave vacuum tubes. This abstract contains simplifications, and is supplied only for purposes of searching, not to limit or alter the scope or meaning of any claims herein.

Christenson, Todd R. (Albuquerque, NM); Garino, Terry J. (Albuquerque, NM); Venturini, Eugene L. (Albuquerque, NM)

2002-01-01T23:59:59.000Z

175

Permanent-magnet-less synchronous reluctance system  

DOE Patents (OSTI)

A permanent magnet-less synchronous system includes a stator that generates a magnetic revolving field when sourced by an alternating current. An uncluttered rotor is disposed within the magnetic revolving field and spaced apart from the stator to form an air gap relative to an axis of rotation. The rotor includes a plurality of rotor pole stacks having an inner periphery biased by single polarity of a north-pole field and a south-pole field, respectively. The outer periphery of each of the rotor pole stacks are biased by an alternating polarity.

Hsu, John S

2012-09-11T23:59:59.000Z

176

High speed flywheel  

DOE Patents (OSTI)

A flywheel for operation at high speeds utilizes two or more ringlike coments arranged in a spaced concentric relationship for rotation about an axis and an expansion device interposed between the components for accommodating radial growth of the components resulting from flywheel operation. The expansion device engages both of the ringlike components, and the structure of the expansion device ensures that it maintains its engagement with the components. In addition to its expansion-accommodating capacity, the expansion device also maintains flywheel stiffness during flywheel operation.

McGrath, Stephen V. (Knoxville, TN)

1991-01-01T23:59:59.000Z

177

Evaluation of a Variable-Speed Centrifugal Compressor with Magnetic...  

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

interna- tional chiller companies. Introduction Investigating ways to reduce energy consumption and costs, the Navy Techval program sponsored a series of demonstra- tions of a new...

178

Best Practices for Energy Efficient Cleanrooms: Variable Speed Pumping  

E-Print Network (OSTI)

efficiency of chilled water and condenser pumps, along with chiller efficiency and cooling tower efficiency for cleanrooms and their adjacent spaces. Chillers 39% Cooling Towers 7% Pumps 17% MUAH + RCU Fans 9% Hot Water facility #12;Chiller Power (kW) 62% Chilled Water Pumps Power (kW) 13% Cooling Tower Power (kW) 20

179

Variable Speed Fan Retrofits for Computer Room Air Conditioners  

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

Case study describes various concepts for more cost-effective cooling solutions in data centers, while keeping in mind that the reliability of computing systems and their respective cooling systems is always a key criterion.

180

Adaptive pitch control for variable speed wind turbines  

DOE Patents (OSTI)

An adaptive method for adjusting blade pitch angle, and controllers implementing such a method, for achieving higher power coefficients. Average power coefficients are determined for first and second periods of operation for the wind turbine. When the average power coefficient for the second time period is larger than for the first, a pitch increment, which may be generated based on the power coefficients, is added (or the sign is retained) to the nominal pitch angle value for the wind turbine. When the average power coefficient for the second time period is less than for the first, the pitch increment is subtracted (or the sign is changed). A control signal is generated based on the adapted pitch angle value and sent to blade pitch actuators that act to change the pitch angle of the wind turbine to the new or modified pitch angle setting, and this process is iteratively performed.

Johnson, Kathryn E. (Boulder, CO); Fingersh, Lee Jay (Westminster, CO)

2012-05-08T23:59:59.000Z

Note: This page contains sample records for the topic "variable speed permanent" 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

Best Practice for Energy Efficient Cleanrooms: Variable Speed Pumping  

E-Print Network (OSTI)

e.g. , chilled water pumps, or condenser water pumps, systemCooling tower and condenser water systems ? Free cooling ?of chilled water and condenser pumps, along with chiller

Xu, Tengfang

2005-01-01T23:59:59.000Z

182

Best Practice for Energy Efficient Cleanrooms: Variable Speed Pumping  

E-Print Network (OSTI)

chiller efficiency ? Cooling tower and condenser waterchiller efficiency and cooling tower efficiency, is a majorMUAH + RCU Fans Pumps Cooling Towers Figure 1. Benchmarked

Xu, Tengfang

2005-01-01T23:59:59.000Z

183

High speed transient sampler  

DOE Patents (OSTI)

A high speed sampler comprises a meandered sample transmission line for transmitting an input signal, a straight strobe transmission line for transmitting a strobe signal, and a plurality of sampling gates along the transmission lines. The sampling gates comprise a four terminal diode bridge having a first strobe resistor connected from a first terminal of the bridge to the positive strobe line, a second strobe resistor coupled from the third terminal of the bridge to the negative strobe line, a tap connected to the second terminal of the bridge and to the sample transmission line, and a sample holding capacitor connected to the fourth terminal of the bridge. The resistance of the first and second strobe resistors is much higher than the signal transmission line impedance in the preferred system. This results in a sampling gate which applies a very small load on the sample transmission line and on the strobe generator. The sample holding capacitor is implemented using a smaller capacitor and a larger capacitor isolated from the smaller capacitor by resistance. The high speed sampler of the present invention is also characterized by other optimizations, including transmission line tap compensation, stepped impedance strobe line, a multi-layer physical layout, and unique strobe generator design. A plurality of banks of such samplers are controlled for concatenated or interleaved sample intervals to achieve long sample lengths or short sample spacing. 17 figs.

McEwan, T.E.

1995-11-28T23:59:59.000Z

184

High speed transient sampler  

DOE Patents (OSTI)

A high speed sampler comprises a meandered sample transmission line for transmitting an input signal, a straight strobe transmission line for transmitting a strobe signal, and a plurality of sampling gates along the transmission lines. The sampling gates comprise a four terminal diode bridge having a first strobe resistor connected from a first terminal of the bridge to the positive strobe line, a second strobe resistor coupled from the third terminal of the bridge to the negative strobe line, a tap connected to the second terminal of the bridge and to the sample transmission line, and a sample holding capacitor connected to the fourth terminal of the bridge. The resistance of the first and second strobe resistors is much higher than the signal transmission line impedance in the preferred system. This results in a sampling gate which applies a very small load on the sample transmission line and on the strobe generator. The sample holding capacitor is implemented using a smaller capacitor and a larger capacitor isolated from the smaller capacitor by resistance. The high speed sampler of the present invention is also characterized by other optimizations, including transmission line tap compensation, stepped impedance strobe line, a multi-layer physical layout, and unique strobe generator design. A plurality of banks of such samplers are controlled for concatenated or interleaved sample intervals to achieve long sample lengths or short sample spacing.

McEwan, Thomas E. (Livermore, CA)

1995-01-01T23:59:59.000Z

185

Counterrotating brushless dc permanent magnet motor  

DOE Patents (OSTI)

An brushless DC permanent magnet motor is provided for driving an autonomous underwater vehicle. In one embodiment, the motor comprises four substantially flat stators disposed in stacked relationship, with pairs of the stators being axially spaced and each of the stators comprising a tape-wound stator coil; and a first and second substantially flat rotors disposed between the spaced pairs of stators. Each of the rotors includes an annular array of permanent magnets embedded therein. A first shaft is connected to the first rotor and a second, concentric shaft is connected to the second rotor, and drive unit causes rotation of the two shafts in opposite directions. The second shaft comprises a hollow tube having a central bore therein in which the first shaft is disposed. Two different sets of bearings support the first and second shAfts. In another embodiment, the motor comprises two ironless stators and pairs and rotors mounted no opposite sides of the stators and driven by counterrotating shafts.

Hawsey, R.A.; Bailey, J.M.

1990-12-31T23:59:59.000Z

186

Counterrotating brushless dc permanent magnet motor  

DOE Patents (OSTI)

An brushless DC permanent magnet motor is provided for driving an autonomous underwater vehicle. In one embodiment, the motor comprises four substantially flat stators disposed in stacked relationship, with pairs of the stators being axially spaced and each of the stators comprising a tape-wound stator coil; and a first and second substantially flat rotors disposed between the spaced pairs of stators. Each of the rotors includes an annular array of permanent magnets embedded therein. A first shaft is connected to the first rotor and a second, concentric shaft is connected to the second rotor, and drive unit causes rotation of the two shafts in opposite directions. The second shaft comprises a hollow tube having a central bore therein in which the first shaft is disposed. Two different sets of bearings support the first and second shAfts. In another embodiment, the motor comprises two ironless stators and pairs and rotors mounted no opposite sides of the stators and driven by counterrotating shafts.

Hawsey, R.A.; Bailey, J.M.

1990-01-01T23:59:59.000Z

187

High Speed Particle Image Velocimetry Overview  

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

Speed Particle Image Velocimetry Speed Particle Image Velocimetry Overview The Department of Energy's National Energy Technology Laboratory is seeking licensing partners interested in implementing U.S. Non- provisional Patent Application 12/765,317 entitled "Method of Particle Trajectory Recognition in Particle Flows of High Particle Concentration Using a Candidate Trajectory Tree Process with Variable Search Areas." This patent application discloses a novel method to simultaneously track the motion of high numbers of object images under extreme, high concen- tration conditions. Although the software is designed to simultaneously track large numbers of particle images in flow fields, it can track any type of object whose locations are available at consecutive time increments (e.g.,

188

TWO-SPEED DEVICE  

DOE Patents (OSTI)

A two-speed device is described comprising a two-part stop engageable with a follower. The two-pant stop comprises first and second members in threaded engagement with each other. The first member is restrained against rotation but is free to move longitudinally, and the second member is free to move arially and rotatively. Means are provided to impart rotation to the second member. The follower is engageable first with an end of one member and then with the corresponding end of the other member after some relative longitudinal movement of the members with respect to one another due to the rotation of the second member and the holding of the first member against rotation.

Brunson, G.S. Jr.

1961-04-01T23:59:59.000Z

189

16,000-rpm Interior Permanent Magnet Reluctance Machine with Brushless Field Excitation  

SciTech Connect

The reluctance interior permanent magnet (RIPM) motor is currently used by many leading auto manufacturers for hybrid vehicles. The power density for this type of motor is high compared with that of induction motors and switched reluctance motors. The primary drawback of the RIPM motor is the permanent magnet (PM) because during high-speed operation, the fixed PM produces a huge back electromotive force (emf) that must be reduced before the current will pass through the stator windings. This reduction in back-emf is accomplished with a significant direct-axis (d-axis) demagnetization current, which opposes the PM's flux to reduce the flux seen by the stator wires. This may lower the power factor and efficiency of the motor and raise the requirement on the alternate current (ac) power supply; consequently, bigger inverter switching components, thicker motor winding conductors, and heavier cables are required. The direct current (dc) link capacitor is also affected when it must accommodate heavier harmonic currents. It is commonly agreed that, for synchronous machines, the power factor can be optimized by varying the field excitation to minimize the current. The field produced by the PM is fixed and cannot be adjusted. What can be adjusted is reactive current to the d-axis of the stator winding, which consumes reactive power but does not always help to improve the power factor. The objective of this project is to avoid the primary drawbacks of the RIPM motor by introducing brushless field excitation (BFE). This offers both high torque per ampere (A) per core length at low speed by using flux, which is enhanced by increasing current to a fixed excitation coil, and flux, which is weakened at high speed by reducing current to the excitation coil. If field weakening is used, the dc/dc boost converter used in a conventional RIPM motor may be eliminated to reduce system costs. However, BFE supports a drive system with a dc/dc boost converter, because it can further extend the constant power speed range of the drive system and adjust the field for power factor and efficiency gains. Lower core losses at low torque regions, especially at high speeds, are attained by reducing the field excitation. Safety and reliability are increased by weakening the field when a winding short-circuit fault occurs, preventing damage to the motor. For a high-speed motor operating at 16,000-revolutions per minute (rpm), mechanical stress is a challenge. Bridges that link the rotor punching segments together must be thickened for mechanical integrity; consequently, increased rotor flux leakage significantly lowers motor performance. This barrier can be overcome by BFE to ensure sufficient rotor flux when needed.

Hsu, J.S.; Burress, T.A.; Lee, S.T.; Wiles, R.H.; Coomer, C.L.; McKeever, J.W.; Adams, D.J.

2007-10-31T23:59:59.000Z

190

Electromagnetic Analysis of Rotating Permanent Magnet Exciters for Hydroelectric Generators.  

E-Print Network (OSTI)

??The purpose of this project is to analyse different design possibilities for a rotating permanent magnet exciter for a hydroelectric generator. This is done through… (more)

Nöland, Jonas

2013-01-01T23:59:59.000Z

191

Can Satellite Sampling of Offshore Wind Speeds Realistically Represent Wind Speed Distributions? Part II: Quantifying Uncertainties Associated with Distribution Fitting Methods  

Science Conference Proceedings (OSTI)

Remote sensing tools represent an attractive proposition for measuring wind speeds over the oceans because, in principle, they also offer a mechanism for determining the spatial variability of flow. Presented here is the continuation of research ...

S. C. Pryor; M. Nielsen; R. J. Barthelmie; J. Mann

2004-05-01T23:59:59.000Z

192

Power-Factor 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 with consideration of the cross saturation between the direct-axis (d-axis) and the 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.

Lee, Seong T [ORNL; Burress, Timothy A [ORNL; Hsu, John S [ORNL

2009-01-01T23:59:59.000Z

193

Engine idle speed control system  

SciTech Connect

An idle speed control system is described for an internal combustion engine having a fuel delivery means for supplying fuel to the engine, the idle speed control system comprising in combination: means for controlling the fuel delivery means to supply a scheduled idle fuel quantity during a idle operating state of the engine; means for sensing the engine idle speed; integrator means responsive to the engine idle speed and a desired engine idle speed for adjusting the scheduled idle fuel quantity in direction and amount to cause correspondence between the engine idle speed and the desired engine idle speed, the integrator means adjustment being a measure of engine load conditions; and means for establishing the scheduled idle fuel quantity, the means including (A) means for establishing a family of curves as a function of the amount of integrator adjustment of the scheduled idle fuel quantity, each curve of the family of curves representing idle fuel quantity as a function of engine idle speed for a respective engine load condition, and (B) means for selecting the curve corresponding to the integrator adjustment of the scheduled idle fuel quantity and providing the scheduled fuel quantity from the selected curve in accord with the sensed engine idle speed.

Ament, F.

1986-07-01T23:59:59.000Z

194

Energy harvesting Wheel Speed Sensor.  

E-Print Network (OSTI)

??This thesis presents a prototype energy harvesting autonomous sensor, called the Autonomous Wheel Speed Sensor (AWSS), that is targeted for operation in the Electronic Braking… (more)

Parthasarathy, Dhasarathy

2012-01-01T23:59:59.000Z

195

A comparative study of various intelligent based controllers for speed control of IPMSM drives in the field-weakening region  

Science Conference Proceedings (OSTI)

Precise speed control of an Interior Permanent Magnet Synchronous Motor (IPMSM) drive becomes a complex issue due to the nonlinear nature of its developed torque. The system nonlinearity becomes severe when the IPMSM drive operates in the field weakening ... Keywords: BELBIC, Flux weakening control, Fuzzy logic controller, Genetic algorithm, IPMSM, Maximum Torque Per Ampere

Behzad Mirzaeian Dehkordi; Arash Kiyoumarsi; Pegah Hamedani; Caro Lucas

2011-09-01T23:59:59.000Z

196

Virable speed gas-turbine drivers gain in compressor use  

SciTech Connect

Variable-speed drivers, such as gas turbines, for reciprocating compressors enhance overall energy savings and a compressor's operational flexibility. This paper presents the main design aspects of gas-turbine systems and some examples from a recent installation in Germany.

Giacomelli, E.; Bernardini, F. (Nuovo Pignone, Florence (Italy)); Andree, H. (Pipeline Engineering GmbH, Essen (DE))

1990-11-19T23:59:59.000Z

197

Permanent magnet energy conversion machine with magnet mounting arrangement  

DOE Patents (OSTI)

A hybrid permanent magnet dc motor includes three sets of permanent magnets supported by the rotor and three sets of corresponding stators fastened to the surrounding frame. One set of magnets operates across a radial gap with a surrounding radial gap stator, and the other two sets of magnets operate off the respective ends of the rotor across respective axial gaps.

Hsu, John S. (Oak Ridge, TN); Adams, Donald J. (Knoxville, TN)

1999-01-01T23:59:59.000Z

198

FOR NUCLEAR POWER PLANTS DURING DECOMMISSIONING AND PERMANENT SHUTDOWN  

E-Print Network (OSTI)

This guide has been developed to describe methods acceptable to the NRC staff for complying with the NRC’s regulations regarding fire protection programs for licensees who have certified that their plants have permanently ceased operations and that the fuel has been permanently removed from the reactor vessels.

A. Introduction

2001-01-01T23:59:59.000Z

199

Ironless Permanent Magnet Motors: Three-Dimensional Analytical Calculation  

E-Print Network (OSTI)

1 Ironless Permanent Magnet Motors: Three-Dimensional Analytical Calculation Romain Ravaud, Guy and the rotor of an ironless permanent magnet motor. The calculations are carried out without using any, torque, magnetic field, PM Synchronous motors ! 1 INTRODUCTION IRONLESS electrical machines are generally

Paris-Sud XI, Université de

200

IDENTIFYING ABBERANT SEGMENTS IN PERMANENT DOWNHOLE GAUGE DATA  

E-Print Network (OSTI)

for interpretation of subsurface conditions in a well. The data from permanent downhole gauges are voluminous the world supplying continuous real time data about subsurface reservoir conditions. Permanent downhole gauges are used in reservoir monitoring and management by interpreting the pressure, flow rate

Note: This page contains sample records for the topic "variable speed permanent" 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

wind speed | OpenEI  

Open Energy Info (EERE)

speed speed Dataset Summary Description GIS data for offshore wind speed (meters/second). Specified to Exclusive Economic Zones (EEZ).Wind resource based on NOAA blended sea winds and monthly wind speed at 30km resolution, using a 0.11 wind sheer to extrapolate 10m - 90m. Annual average >= 10 months of data, no nulls. Source National Renewable Energy Laboratory (NREL) Date Released Unknown Date Updated Unknown Keywords GIS global NOAA NREL offshore wind wind speed Data application/zip icon Download Shapefile (zip, 18.5 MiB) Quality Metrics Level of Review Some Review Comment Temporal and Spatial Coverage Frequency Time Period License License Other or unspecified, see optional comment below Comment Please cite NREL and NOAA Rate this dataset Usefulness of the metadata

202

The search for permanent electric dipole moments  

SciTech Connect

Permanent electric dipole moments (EDMs) of fundamental systems with spin - particles, nuclei, atoms or molecules violate parity and time reversal invariance. Invoking the CPT theorem, time reversal violation implies CP violation. Although CP-violation is implemented in the standard electro-weak theory, EDM generated this way remain undetectably small. However, this CP-violation also appears to fail explaining the observed baryon asymmetry of our universe. Extensions of the standard theory usually include new sources of CP violation and often predict sizeable EDMs. EDM searches in different systems are complementary and various efforts worldwide are underway and no finite value has been established yet. The prototype of an EDM search is the pursuit of the EDM of the neutron. It has the longest history and at the same time is at the forefront of present research. The talk aims at giving an overview of the field with emphasis on our efforts within an international collaboration at PSI, nedm.web.psi.ch.

Kirch, Klaus [PSI-Villigen - ETH Zürich

2013-02-13T23:59:59.000Z

203

Heading off the permanent oil crisis  

SciTech Connect

The 1996 spike in gasoline prices was not a signal of any fundamental worldwide shortage of crude oil. But based on a review of many studies of recoverable crude oil that have been published since the 1950s, it looks as though such a shortfall is now within sight. With world demand for oil growing at 2 percent per year, global production is likely to peak between the years 2007 and 2014. As this time approaches, we can expect prices to rise markedly and, most likely, permanently. Policy changes are needed now to ease the transition to high-priced oil. Oil production will continue, though at a declining rate, for many decades after its peak, and there are enormous amounts of coal, oil sands, heavy oil, and oil shales worldwide that could be used to produce liquid or gaseous substitutes for crude oil, albeit at higher prices. But the facilities for making such synthetic fuels are costly to build and environmentally damaging to operate, and their use would substantially increase carbon dioxide emissions (compared to emissions from products made from conventional crude oil). This paper examines ways of heading of the impending oil crisis. 8 refs., 3 figs.

MacKenzie, J.J. [World Resources Inst., Washington, DC (United States)

1996-11-01T23:59:59.000Z

204

Numerical wind speed simulation model  

DOE Green Energy (OSTI)

A relatively simple stochastic model for simulating wind speed time series that can be used as an alternative to time series from representative locations is described in this report. The model incorporates systematic seasonal variation of the mean wind, its standard deviation, and the correlation speeds. It also incorporates systematic diurnal variation of the mean speed and standard deviation. To demonstrate the model capabilities, simulations were made using model parameters derived from data collected at the Hanford Meteorology Station, and results of analysis of simulated and actual data were compared.

Ramsdell, J.V.; Athey, G.F.; Ballinger, M.Y.

1981-09-01T23:59:59.000Z

205

Variable Screw Compressor, Variable Screw Compressor Suppliers ...  

U.S. Energy Information Administration (EIA)

Variable Screw Compressor Suppliers & air compressor Manufacturers Directory. Source Top Quality Variable Screw Compressor Suppliers, air ...

206

Spatial Predictions of Extreme Wind Speeds over Switzerland Using Generalized Additive Models  

Science Conference Proceedings (OSTI)

The purpose of this work is to present a methodology aimed at predicting extreme wind speeds over Switzerland. Generalized additive models are used to regionalize wind statistics for Swiss weather stations using a number of variables that ...

Christophe Etienne; Anthony Lehmann; Stéphane Goyette; Juan-Ignacio Lopez-Moreno; Martin Beniston

2010-09-01T23:59:59.000Z

207

Adjustable speed drives: Applications and R&D needs  

SciTech Connect

The largest opportunity for the growth of adjustable speed drives (ASDs) during the next 5-6 years is in pump, fan and compressor (PFC) applications where a constant, fixed speed operation is converted to adjustable speed in order to realize energy savings. Inverter supplied induction motors are and will continue to be predominately used in these applications. Over the long term (10-15 years), the greatest ASD growth is expected in large volume consumer applications: first in hybrid electric vehicles (EVs) and in residential heating, ventilation and air-conditioning (HVAC). Both induction and a variety of AC Permanent Magnet motors are expected to be the dominant technology in this new field. The traditional ASD applications in industries which require adjustable speed (such as machine tools, robotics, steel rolling, extruders, paper mill finishing lines, etc.) offer a relatively limited potential for above average ASD growth since most of these applications have already converted to electronic speed control. As a result, ASD growth in this sector will essentially track the growth of the corresponding industries. If realized, both short and long term ASD growth opportunities will result in significant advancements of ASD technology, which will then substantially affect all other, more fragmented, ASD applications. In fact, any single large volume ASD application will serve as a catalyst for improving ASD characteristics in all other ASD applications with the same voltage rating. ASD cost and reliability (defined in the context of application compatibility) are the two most important factors which will determine whether the ASD growth opportunities are realized. Conversely, any technological improvement which carries a cost increase will be restricted to niche applications, at best. Consequently, future R & D efforts should be directed to secure reduction in ASD cost and improvement in ASD reliability. A specific action plan is outlined in this report.

Stefanovic, V.R.

1995-09-01T23:59:59.000Z

208

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.

209

Wind Speed Forecasting for Power System Operation  

E-Print Network (OSTI)

In order to support large-scale integration of wind power into current electric energy system, accurate wind speed forecasting is essential, because the high variation and limited predictability of wind pose profound challenges to the power system operation in terms of the efficiency of the system. The goal of this dissertation is to develop advanced statistical wind speed predictive models to reduce the uncertainties in wind, especially the short-term future wind speed. Moreover, a criterion is proposed to evaluate the performance of models. Cost reduction in power system operation, as proposed, is more realistic than prevalent criteria, such as, root mean square error (RMSE) and absolute mean error (MAE). Two advanced space-time statistical models are introduced for short-term wind speed forecasting. One is a modified regime-switching, space-time wind speed fore- casting model, which allows the forecast regimes to vary according to the dominant wind direction and seasons. Thus, it avoids a subjective choice of regimes. The other one is a novel model that incorporates a new variable, geostrophic wind, which has strong influence on the surface wind, into one of the advanced space-time statistical forecasting models. This model is motivated by the lack of improvement in forecast accuracy when using air pressure and temperature directly. Using geostrophic wind in the model is not only critical, it also has a meaningful geophysical interpretation. The importance of model evaluation is emphasized in the dissertation as well. Rather than using RMSE or MAE, the performance of both wind forecasting models mentioned above are assessed by economic benefits with real wind farm data from Pacific Northwest of the U.S and West Texas. Wind forecasts are incorporated into power system economic dispatch models, and the power system operation cost is used as a loss measure for the performance of the forecasting models. From another perspective, the new criterion leads to cost-effective scheduling of system-wide wind generation with potential economic benefits arising from the system-wide generation of cost savings and ancillary services cost savings. As an illustration, the integrated forecasts and economic dispatch framework are applied to the Electric Reliability Council of Texas (ERCOT) equivalent 24- bus system. Compared with persistence and autoregressive models, the first model suggests that cost savings from integration of wind power could be on the scale of tens of millions of dollars. For the second model, numerical simulations suggest that the overall generation cost can be reduced by up to 6.6% using look-ahead dispatch coupled with spatio-temporal wind forecast as compared with dispatch with persistent wind forecast model.

Zhu, Xinxin

2013-08-01T23:59:59.000Z

210

A doubly-fed permanent magnet generator for wind turbines  

E-Print Network (OSTI)

Optimum extraction of energy from a wind turbine requires that turbine speed vary with wind speed. Existing solutions to produce constant-frequency electrical output under windspeed variations are undesirable due to ...

Thomas, Andrew J. (Andrew Joseph), 1981-

2004-01-01T23:59:59.000Z

211

Method and apparatus for assembling permanent magnet rotors  

DOE Patents (OSTI)

A permanent magnet assembly for assembly in large permanent magnet motors and generators includes a two-piece carrier that can be slid into a slot in the rotor and then secured in place using a set screw. The invention also provides an auxiliary carrier device with guide rails that line up with the teeth of the rotor, so that a permanent magnet assembly can be pushed first into a slot, and then down the slot to its proper location. An auxiliary tool is provided to move the permanent magnet assembly into position in the slot before it is secured in place. Methods of assembling and disassembling the magnet assemblies in the rotor are also disclosed. 2 figs.

Hsu, J.S.; Adams, D.J.

1999-06-22T23:59:59.000Z

212

Current Status of Permanent Magnet Research and Market in China  

Science Conference Proceedings (OSTI)

In 2008, China supplied 77.6% of Nd-Fe-B, 55.2% of ferrite and 55.3% of AlNiCo for global permanent magnets market. Financial crisis since 2008 has spurred ...

213

In situ local shock speed and transit shock speed and T. Detman2  

E-Print Network (OSTI)

In situ local shock speed and transit shock speed S. Watari1 and T. Detman2 1 Communications shock observa- tions. This index is the ratio of the in situ local shock speed and the transit speed; it is 0.6±0.9 for most observed shocks. The local shock speed and the transit speed calculated

Paris-Sud XI, Université de

214

Speeding Up Zeolite Evaluation for Carbon Capture  

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

Speeding Up Zeolite Evaluation for Carbon Capture Speeding Up Zeolite Evaluation for Carbon Capture Zeolite.png Schematic of an important class of porous materials known as...

215

Time evolution of fields in strontium ferrite permanent magnets  

SciTech Connect

Field strengths for strontium ferrite permanent magnets built for the Fermilab Recycler and 8 GeV transfer line have been measured for the past 4 years. The ferrite magnetization exhibits a time dependence parameterized by M1/M{sub 2} = -9 x 10{sup -4} x log (t{sub 1}/t{sub 2}) as determined from measurements of a gradient magnet. This parameterization has been checked against several other styles of permanent dipoles, and quadrupole magnets with good agreement.

James T. Volk et al.

2001-06-11T23:59:59.000Z

216

Permanent magnet quadrupoles for the CLIC Drive Beam decelerator  

E-Print Network (OSTI)

STFC in collaboration with CERN has developed a new type of adjustable permanent magnet based quadrupole for the CLIC Drive Beam Decelerator. It uses vertical movement of the permanent magnets to achieve an integrated gradient range of 3.6-14.6T, which will allow it to be used for the first 60% of the decelerator line. Construction of a prototype of this magnet has begun; following this, it will be measured magnetically at CERN and Daresbury Laboratory.

Shepherd, Ben; Collomb, Norbert

2012-01-01T23:59:59.000Z

217

Study of the Advantages of Internal Permanent Magnet Drive Motor with Selectable Windings for Hybrid-Electric Vehicles  

SciTech Connect

This report describes research performed on the viability of changing the effectively active number of turns in the stator windings of an internal permanent magnet (IPM) electric motor to strengthen or weaken the magnetic fields in order to optimize the motor's performance at specific operating speeds and loads. Analytical and simulation studies have been complemented with research on switching mechanisms to accomplish the task. The simulation studies conducted examine the power and energy demands on a vehicle following a series of standard driving cycles and the impact on the efficiency and battery size of an electrically propelled vehicle when it uses an IPM motor with turn-switching capabilities. Both full driving cycle electric propulsion and propulsion limited starting from zero to a set speed have been investigated.

Otaduy, P.J.; Hsu, J.S.; Adams, D.J.

2007-11-30T23:59:59.000Z

218

Orthobaric Density: A Thermodynamic Variable for Ocean Circulation Studies  

Science Conference Proceedings (OSTI)

A new density variable, empirically corrected for pressure, is constructed. This is done by first fitting compressibility (or sound speed) computed from global ocean datasets to an empirical function of pressure and in situ density (or specific ...

Roland A. de Szoeke; Scott R. Springer; David M. Oxilia

2000-11-01T23:59:59.000Z

219

Device for adapting continuously variable transmissions to infinitely variable transmissions with forward-neutral-reverse capabilities  

DOE Patents (OSTI)

An infinitely variable transmission is capable of operating between a maximum speed in one direction and a minimum speed in an opposite direction, including a zero output angular velocity, while being supplied with energy at a constant angular velocity. Input energy is divided between a first power path carrying an orbital set of elements and a second path that includes a variable speed adjustment mechanism. The second power path also connects with the orbital set of elements in such a way as to vary the rate of angular rotation thereof. The combined effects of power from the first and second power paths are combined and delivered to an output element by the orbital element set. The transmission can be designed to operate over a preselected ratio of forward to reverse output speeds.

Wilkes, Donald F. (Albuquerque, NM); Purvis, James W. (Albuquerque, NM); Miller, A. Keith (Albuquerque, NM)

1997-01-01T23:59:59.000Z

220

Alternative Fuels Data Center: Low-Speed Vehicle and Medium-Speed Electric  

Alternative Fuels and Advanced Vehicles Data Center (EERE)

Low-Speed Vehicle and Low-Speed Vehicle and Medium-Speed Electric Vehicle (EV) Access to Roadways to someone by E-mail Share Alternative Fuels Data Center: Low-Speed Vehicle and Medium-Speed Electric Vehicle (EV) Access to Roadways on Facebook Tweet about Alternative Fuels Data Center: Low-Speed Vehicle and Medium-Speed Electric Vehicle (EV) Access to Roadways on Twitter Bookmark Alternative Fuels Data Center: Low-Speed Vehicle and Medium-Speed Electric Vehicle (EV) Access to Roadways on Google Bookmark Alternative Fuels Data Center: Low-Speed Vehicle and Medium-Speed Electric Vehicle (EV) Access to Roadways on Delicious Rank Alternative Fuels Data Center: Low-Speed Vehicle and Medium-Speed Electric Vehicle (EV) Access to Roadways on Digg Find More places to share Alternative Fuels Data Center: Low-Speed

Note: This page contains sample records for the topic "variable speed permanent" 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

OpenEI - wind speed  

Open Energy Info (EERE)

NREL GIS Data: Global NREL GIS Data: Global Offshore Wind http://en.openei.org/datasets/node/869 GIS data for offshore wind speed (meters/second).  Specified to Exclusive Economic Zones (EEZ).Wind resource based on NOAA blended sea winds and monthly wind speed at 30km resolution, using a 0.11 wind sheer to extrapolate 10m - 90m.  Annual average  >= 10 months of data, no nulls. License

Type of License:  Other (please specify below)

222

High-Speed Optical and Electrical Measurements  

Science Conference Proceedings (OSTI)

High-Speed Optical and Electrical Measurements. The Optoelectronics Division provides three different services related ...

2011-12-15T23:59:59.000Z

223

1980–2010 Variability in U.K. Surface Wind Climate  

Science Conference Proceedings (OSTI)

The climate of the northeast Atlantic region comprises substantial decadal variability in storminess. It also exhibits strong inter- and intra-annual variability in extreme high and low wind speed episodes. Here the authors quantify and discuss ...

Nick Earl; Steve Dorling; Richard Hewston; Roland von Glasow

2013-02-01T23:59:59.000Z

224

Effects of Weather Variables on Pedestrian Volumes in Alameda County, California  

E-Print Network (OSTI)

within 1/4?mile  Weather  Average hourly solar radiation 2 weather stations. Air temperature, precipitation, solarWeather Variables Binary dummy variables were used to capture possible non-linear effects of temperature, wind speed, solar

Attaset, Vanvisa; Schneider, Robert J.; Arnold, Lindsay S.; Ragland, David R

2010-01-01T23:59:59.000Z

225

Control of Two Permanent Magnet Machines Using a Five-Leg Inverter for Automotive Applications  

SciTech Connect

This paper presents digital control schemes for control of two permanent magnet (PM) machines in an integrated traction and air-conditioning compressor drive system for automotive applications. The integrated drive system employs a five-leg inverter to power a three-phase traction PM motor and a two-phase compressor PM motor by tying the common terminal of the two-phase motor to the neutral point of the three-phase motor. Compared to a three-phase or a standalone two-phase inverter, it eliminates one phase leg and shares the control electronics between the two drives, thus significantly reducing the component count of the compressor drive. To demonstrate that the speed and torque of the two PM motors can be controlled independently, a control strategy was implemented in a digital signal processor, which includes a rotor flux field orientation based control (RFOC) for the three-phase motor, a similar RFOC and a position sensorless control in the brushless dc (BLDC) mode for the two-phase motor. Control implementation issues unique to a two-phase PM motor are also discussed. Test results with the three-phase motor running in the ac synchronous (ACS) mode while the two-phase motor either in the ACS or the BLDC mode are included to verify the independent speed and torque control capability of the integrated drive.

Su, Gui-Jia [ORNL; Tang, Lixin [ORNL; Huang, Xianghui [GE Global Research

2006-01-01T23:59:59.000Z

226

High Speed ADC Design Methodology  

E-Print Network (OSTI)

545. [11] Siqiang Fan, “High Speed ADC Design Techniques”,Fan, Xin Wang, Lin Lin, Qiang Fang, Jian Liu and Albert Wang, “DesignFan, Xin Wang, Lin Lin, Qiang Fang, Jian Liu, Bin Zhao and Albert Wang, “Capacitive Interpolated Flash ADC Design

Tang, He

2010-01-01T23:59:59.000Z

227

Predictors of Social Mobilization Speed  

E-Print Network (OSTI)

social mobilization, mobilization speed, demographics Acknowledgement: The authors would like to thank Anton Phillips for operational and financial support as the general manager at Langley Castle, Sunny Cheung for designing and implementing the web site software, and Wei Pan for insights and suggestions based on his experience with the Red Balloon experiment. The authors would also like to thank Roy Welsch and Frank Harrell for their help in statistical interpretation. Contact Stuart Madnick for access to the contest data. Mobilization across social networks is becoming increasingly influential, but little is known about what traits of individuals and their relationships affect their speed of mobilization between them. We ran a global social mobilization contest and recorded personal traits of the participants and those they mobilized. We examined how those traits influenced the speed of mobilization. Individuals mobilized faster when they heard about the contest directly from the contest organization, and decreased in speed when hearing from less personal source types (e.g. family vs. media). Mobilization was faster when the mobilizer and

Jeff Alstott; Stuart Madnick; Chander Velu; Jeff Alstott Stuart Madnick

2013-01-01T23:59:59.000Z

228

Experience with the procurement of ferrite and temperature compensator for permanent magnets for accelerators  

E-Print Network (OSTI)

Experience with the procurement of ferrite and temperature compensator for permanent magnets for accelerators

Fowler, W B; Volk, J T

1998-01-01T23:59:59.000Z

229

Using Electronic Adjustable Speed Drives for Efficiency Improvement and Cost Reduction  

E-Print Network (OSTI)

U.S. industry and utilities have been using ac adjustable speed drives (ASDs) for more than 50 years. ASDs utilize power electronics technology to control the flow of power to an ac motor, thereby controlling the motor’s speed and rate of energy consumption while modulating process flow through the fan or pump driven by the motor. Industrial ASD applications have typically been those requiring extremely precise speed control, such as in fiber spinning operations with multiple motors. However, controlling process flow by varying the speed in many systems does not require the fast-responding, precise wide speed range regenerative drives frequently needed for “traditional” variable speed applications. Often the required speed range is small and there is limited or no requirement for speed of response and speed control precision. Electronic ASDs have come a long way since their introduction some ten years ago. These drives, which match motor speed to the job with the help of semiconductor devices and switching circuits, have become progressively more efficient and versatile. The cost of electronic ASDs has declined rapidly over the last three years. Pending technology advances promise to make the drives even more attractive in the future, both from a performance as well as a cost standpoint.

Friedman, N. R.

1989-09-01T23:59:59.000Z

230

Design of an ambient aerosol sampling system for high and medium speed applications  

E-Print Network (OSTI)

Two ambient sampling systems were designed and tested for high speed sampling application for a wind speed range of 4.47 m/s to 26.82 m/s. These systems will be used as inlets for sampling of bioaerosol from air. These systems consist of shrouded probes for sampling at higher speeds and omni-directional inlets for low speed ambient sampling. The two systems operate at 780 L/min and 90 L/min. Another system was designed and tested for medium speed ambient sampling. This unit will be used as a reference sampler for speed ranges from zero to 20.12 m/s. This system consists of a Sierra-Andersen SA-246 inlet for sampling at speeds up-to 6.71 m/s (15 mph) and a shrouded probe operating at variable flow rate for sampling in speed range of 6.71 m/s and 20.12 m/s. An aircraft-borne shrouded probe was also tested at wind speeds as high as 50 m/s in an upgraded high speed wind tunnel.

Irshad, Hammad

2002-01-01T23:59:59.000Z

231

Optimizing Energy Savings from Direct-DC in U.S. Residential Buildings  

E-Print Network (OSTI)

brushless DC permanent magnet motor EV electric vehicle BtuBrushless DC permanent magnet motors can save 5-15% of theBrushless DC permanent magnet motor; VSD: Variable-speed

Garbesi, Karina

2012-01-01T23:59:59.000Z

232

Catalog of DC Appliances and Power Systems  

E-Print Network (OSTI)

Brushless DC permanent magnet motor EV electric vehicle Btubrushless DC permanent magnet motors [11]. We note that themotor 2 Same VSD = variable speed drive BDCPM = brushless DC permanent magnet

Garbesi, Karina

2012-01-01T23:59:59.000Z

233

Permanent-magnet-less machine having an enclosed air gap  

DOE Patents (OSTI)

A permanent magnet-less, brushless synchronous system includes a stator that generates a magnetic rotating field when sourced by an alternating current. An uncluttered rotor disposed within the magnetic rotating field is spaced apart from the stator to form an air gap relative to an axis of rotation. A stationary excitation core spaced apart from the uncluttered rotor by an axial air gap and a radial air gap substantially encloses the stationary excitation core. Some permanent magnet-less, brushless synchronous systems include stator core gaps to reduce axial flux flow. Some permanent magnet-less, brushless synchronous systems include an uncluttered rotor coupled to outer laminations. The quadrature-axis inductance may be increased in some synchronous systems. Some synchronous systems convert energy such as mechanical energy into electrical energy (e.g., a generator); other synchronous systems may convert any form of energy into mechanical energy (e.g., a motor).

Hsu, John S. (Oak Ridge, TN)

2012-02-07T23:59:59.000Z

234

Permanent-magnet-less machine having an enclosed air gap  

SciTech Connect

A permanent magnet-less, brushless synchronous system includes a stator that generates a magnetic rotating field when sourced by an alternating current. An uncluttered rotor disposed within the magnetic rotating field is spaced apart from the stator to form an air gap relative to an axis of rotation. A stationary excitation core spaced apart from the uncluttered rotor by an axial air gap and a radial air gap substantially encloses the stationary excitation core. Some permanent magnet-less, brushless synchronous systems include stator core gaps to reduce axial flux flow. Some permanent magnet-less, brushless synchronous systems include an uncluttered rotor coupled to outer laminations. The quadrature-axis inductance may be increased in some synchronous systems. Some synchronous systems convert energy such as mechanical energy into electrical energy (e.g., a generator); other synchronous systems may convert any form of energy into mechanical energy (e.g., a motor).

Hsu, John S.

2013-03-05T23:59:59.000Z

235

Radial-Gap Permanent Magnet Motor and Drive Research FY 2004  

SciTech Connect

The objective of this task was to study permanent magnet (PM) radial-gap traction drive systems that could meet the U.S. Department of Energy FreedomCAR Program's 2010 goals to expose weaknesses or identify strengths. Initially, the approach was to compare attributes such as physical deformations during operation, performance (torque, power, efficiency versus speed), material requirements (strength), material costs, manufacturability, weight, power density, specific power, reliability, and drivability for specific motors. Three motors selected were the commercially available 60-kW radial-gap surface-mounted PM motor manufactured by UQM Technologies, Inc.; a hypothetical PM motor with rotor-supported magnets similar to the Honda MCF-21; and Delphi's automotive electric machine drive motor, whose rotor is a ferromagnetic cylinder, held at one end by a shaft that supports the magnets on its inner surface. Potential problems have appeared related to PM motors, such as (1) high no-load spin losses and high operational power losses, probably from eddy current losses in the rotor; (2) the undemonstrated dual mode inverter control (DMIC) for driving a brushless dc motor (BDCM) (UQM and Delphi motors); (3) uncertainty about the potential for reducing current with DMIC; and (4) uncertainty about the relation between material requirements and maximum rotor speed. Therefore, the approach was changed to study in detail three of the comparison attributes: drivability, performance, and material requirements. Drivability and related problems were examined by demonstrating that DMIC may be used to drive an 18-pole 30-kW PM motor to 6000 rpm, where the maximum electrical frequency is 900 Hz. An available axial-gap test motor with 18 poles was used because its control is identical to that of a radial gap PM motor. Performance was analytically examined, which led to a derivation showing that DMIC controls a PM motor so that the motor uses minimum current to produce any power regardless of speed for relative speeds, n = {omega}/{omega}{sub base} {ge} 2. Performance was also examined with efficiency measurements during the 30-kW PM motor test. Material requirements were examined with finite-element analyses (FEA) to determine the speed and location where yield starts and the corresponding deformations and stresses.

McKeever, J.W.

2005-02-11T23:59:59.000Z

236

Performance evaluation of a permanent magnet brushless DC linear drive for high-speed machining using finite element analysis  

Science Conference Proceedings (OSTI)

Keywords: FEA, coupled magneto-thermal, electric field, electromagnetic, linear motor drives, magnetic field, static

George Abdou; William Tereshkovich

2000-05-01T23:59:59.000Z

237

From permanence to total availability: a quantum conceptual upgrade  

E-Print Network (OSTI)

We consider the classical concept of time of permanence and observe that its quantum equivalent is described by a bona fide self-adjoint operator. Its interpretation, by means of the spectral theorem, reveals that we have to abandon not only the idea that quantum entities would be characterizable in terms of spatial trajectories but, more generally, that they would possess the very attribute of spatiality. Consequently, a permanence time shouldn't be interpreted as a "time" in quantum mechanics, but as a measure of the total availability of a quantum entity in participating to a creative process of spatial localization.

de Bianchi, Massimiliano Sassoli

2010-01-01T23:59:59.000Z

238

An Improved Sensorless Control System of Permanent Magnet Synchronous Motor  

Science Conference Proceedings (OSTI)

To improve the performance of permanent magnet synchronous motor sensor less control system, the phase offset caused by the low pass filter must be considering. In this paper, to apply the linear control theory to PMSM system. The introduced control ... Keywords: PMSM, Reduced-order Observer, Group Time Delay, Adaptive, Sensorless

Long Tang, Hong-Lin Ou Yang, Chao Meng, Xin-Yuan Li, Xu-Jie Mo

2013-01-01T23:59:59.000Z

239

Permanent Closure of the TAN-664 Underground Storage Tank  

SciTech Connect

This closure package documents the site assessment and permanent closure of the TAN-664 gasoline underground storage tank in accordance with the regulatory requirements established in 40 CFR 280.71, 'Technical Standards and Corrective Action Requirements for Owners and Operators of Underground Storage Tanks: Out-of-Service UST Systems and Closure.'

Bradley K. Griffith

2011-12-01T23:59:59.000Z

240

Adaptive friction compensation for permanent magnet linear synchronous motor  

Science Conference Proceedings (OSTI)

The paper discussed an adaptive friction compensation scheme based on Coulomb friction and a parameter identifier. The model reference adaptive system based on Coulomb friction was designed to compensate the friction on-line. The designed model reference ... Keywords: friction compensation, model reference adaptive control, parameter identification, permanent magnet linear synchronous motor (PMLSM)

Wang Li-Mei; Wu Lin

2009-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "variable speed permanent" 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

Nominal Position Controller for Permanent Magnet Synchronous Motor System  

Science Conference Proceedings (OSTI)

A nonlinear position controller for permanent magnet synchronous motor (PMSM) was designed to achieve position tracing control and robust control. The controller included two parts: the model controller and the robust controller. The former was designed ... Keywords: PMSM, nominal control, sliding mode control

Yuzeng Zhang; Fan Wang; Mingyin Yan

2010-05-01T23:59:59.000Z

242

PERMANENT MAGNET DESIGNS WITH LARGE VARIATIONS IN FIELD STRENGTH.  

Science Conference Proceedings (OSTI)

The use of permanent magnets has been investigated as an option for electron cooling ring for the proposed luminosity upgrade of RHIC. Several methods have been developed that allow a large variation in field strength. These design concepts were verified with computer simulations using finite element codes. It will be shown that the field uniformity is maintained while the field strength is mechanically adjusted.

GUPTA,R.

2004-01-21T23:59:59.000Z

243

Speed control with end cushion for high speed air cylinder  

DOE Patents (OSTI)

A high speed air cylinder in which the longitudinal movement of the piston within the air cylinder tube is controlled by pressurizing the air cylinder tube on the accelerating side of the piston and releasing pressure at a controlled rate on the decelerating side of the piston. The invention also includes a method for determining the pressure required on both the accelerating and decelerating sides of the piston to move the piston with a given load through a predetermined distance at the desired velocity, bringing the piston to rest safely without piston bounce at the end of its complete stroke. 4 figs.

Stevens, W.W.; Solbrig, C.W.

1989-06-20T23:59:59.000Z

244

Extending the Constant Power Speed Range of the Brushless DC Motor through Dual Mode Inverter Control -- Part I: Theory and Simulation  

SciTech Connect

An inverter topology and control scheme has been developed that can drive low-inductance, surface-mounted permanent magnet motors over the wide constant power speed range required in electric vehicle applications. This new controller is called the dual-mode inverter control (DMIC) [1]. The DMIC can drive either the Permanent Magnet Synchronous Machine (PMSM) with sinusoidal back emf, or the brushless dc machine (BDCM) with trapezoidal emf in the motoring and regenerative braking modes. In this paper we concentrate on the BDCM under high-speed motoring conditions. Simulation results show that if all motor and inverter loss mechanisms are neglected, the constant power speed range of the DMIC is infinite. The simulation results are supported by closed form expressions for peak and rms motor current and average power derived from analytical solution to the differential equations governing the DMIC/BDCM drive for the lossless case. The analytical solution shows that the range of motor inductance that can be accommodated by the DMIC is more than an order of magnitude such that the DMIC is compatible with both low- and high-inductance BDCMs. Finally, method is given for integrating the classical hysteresis band current control, used for motor control below base speed, with the phase advance of DMIC that is applied above base speed. The power versus speed performance of the DMIC is then simulated across the entire speed range.

Lawler, J.S.

2001-10-29T23:59:59.000Z

245

High-Speed Trains For California  

E-Print Network (OSTI)

ESTIMATION RESEARCH 3 SCAG: High Speed Rail Fe_aLs~ilityRail Authority, Austin, January. Transportation Research

Hall, Peter; Leavitt, Daniel; Vaca, Erin

1992-01-01T23:59:59.000Z

246

Displacement speeds in turbulent premixed flame simulations  

SciTech Connect

The theory of turbulent premixed flames is based on acharacterization of the flame as a discontinuous surface propagatingthrough the fluid. The displacement speed, defined as the local speed ofthe flame front normal to itself, relative to the unburned fluid,provides one characterization of the burning velocity. In this paper, weintroduce a geometric approach to computing displacement speed anddiscuss the efficacy of the displacement speed for characterizing aturbulent flame.

Day, Marcus S.; Shepherd, Ian G.; Bell, J.; Grcar, Joseph F.; Lijewski, Michael J.

2007-07-01T23:59:59.000Z

247

Speed Control in Industrial Refrigeration: Theory, Application & Case Studies  

E-Print Network (OSTI)

It is often standard practice in the field of industrial refrigeration to design and operate systems with little regard toward part-load performance. This approach is understandable, whether viewed from the standpoint of the design engineer, plant manager or chief operator. As long a space temperature and production rates are maintained during peak periods, the refrigeration system is viewed as operating "correctly". The truth is, most refrigeration systems spend some, if not most operating hours at reduced capacity. Screw compressors back off slide valves, evaporator coils utilize back-pressure regulators (BPRs) or liquid solenoids, and condensers cycle fans. Unfortunately, these control methods do not provide the maximum attainable reduction in brake horsepower (BHP) as refrigeration capacity is reduced. This paper will discuss the application of variable speed drive (VSD, also called "variable frequency drive", "adjustable speed drive", "inverter", or simply "freq. drive") technology to capacity control of screw compressors, evaporator fans, and condenser fans. As shown through theory and case study, speed control of these components provides maximum flexibility, control and energy efficiency.

Wilcox, M. H.

1995-04-01T23:59:59.000Z

248

Advanced Ultra-High Speed Motor for Drilling  

Science Conference Proceedings (OSTI)

Three (3) designs have been made for two sizes, 6.91 cm (2.72 inch) and 4.29 cm (1.69 inch) outer diameters, of a patented inverted configured Permanent Magnet Synchronous Machines (PMSM) electric motor specifically for drilling at ultra-high rotational speeds (10,000 rpm) and that can utilize advanced drilling methods. Benefits of these motors are stackable power sections, full control (speed and direction) of downhole motors, flow hydraulics independent of motor operation, application of advanced drilling methods (water jetting and abrasive slurry jetting), and the ability of signal/power electric wires through motor(s). Key features of the final designed motors are: fixed non-rotating shaft with stator coils attached; rotating housing with permanent magnet (PM) rotor attached; bit attached to rotating housing; internal channel(s) in a nonrotating shaft; electric components that are hydrostatically isolated from high internal pressure circulating fluids ('muds') by static metal to metal seals; liquid filled motor with smoothed features for minimized turbulence in the motor during operation; and new inverted coated metal-metal hydrodynamic bearings and seals. PMSM, Induction and Switched Reluctance Machines (SRM), all pulse modulated, were considered, but PMSM were determined to provide the highest power density for the shortest motors. Both radial and axial electric PMSM driven motors were designed with axial designs deemed more rugged for ultra-high speed, drilling applications. The 6.91 cm (2.72 inch) OD axial inverted motor can generate 4.18KW (5.61 Hp) power at 10,000 rpm with a 4 Nm (2.95 ft-lbs) of torque for every 30.48 cm (12 inches) of power section. The 6.91 cm (2.72 inch) OD radial inverted motor can generate 5.03 KW (6.74 Hp) with 4.8 Nm (3.54 ft-lb) torque at 10,000 rpm for every 30.48 cm (12 inches) of power section. The 4.29 cm (1.69 inch) OD radial inverted motor can generate 2.56 KW (3.43 Hp) power with 2.44 Nm (1.8 ft-lb) torque at full speed 10,000 rpm for every 30.48 cm (12 inches) of power section. Operating conditions are 300 voltage AC at the motor leads. Power voltage losses in the cables/wirelines to the motor(s) are expected to be about 10% for 5000 feet carrying 2 amperes. Higher voltages and better insulators can lower these losses and carry more amperes. Cutting elements for such high tip velocities are currently not available, consequently these motors will not be built at this time. However, 7.62 cm (3 inch) OD, low speed, PMSM radial electric motors based on this project design are being built under a 2006 Oklahoma Center for the Advancement of Science and Technology 'proof of concept' grant.

Impact Technologies LLC; University of Texas at Arlington

2007-03-31T23:59:59.000Z

249

Potential ecological impacts analysis of California high speed rail  

E-Print Network (OSTI)

proposed California High Speed Rail project as detailed inof choosing the high speed rail modal alternative versus theand was based on high speed rail alignment data, including

Cameron, Dick; White, Mike; Stallcup, Jerre Ann; Penrod, Kristeen

2005-01-01T23:59:59.000Z

250

Southeast high speed rail (SEHSR): a case study  

E-Print Network (OSTI)

transportation system. High speed rail service will provide100 – 500 miles. High speed rail in the Southeast will meanto develop a high speed rail network connecting their states

Gallagher, William

2005-01-01T23:59:59.000Z

251

Parameter estimation of permanent magnet stepper motors without position or velocity sensors  

E-Print Network (OSTI)

Parameter estimation of permanent magnet stepper motors without position or velocity sensors Romain identification method for permanent magnet stepper motors. Current sensors are assumed available, but position magnet stepper motors, syn- chronous motors, sensorless systems, parameter identification, elimination

Paris-Sud XI, Université de

252

An issue of permanence: assessing the effectiveness of temporary carbon storage  

E-Print Network (OSTI)

In this paper, we present a method to quantify the effectiveness of carbon mitigation options taking into account the "permanence" of the emissions reduction. While the issue of permanence is most commonly associated with ...

Herzog, Howard J.

253

Disc rotors with permanent magnets for brushless DC motor  

DOE Patents (OSTI)

A brushless dc permanent magnet motor drives an autonomous underwater vehe. In one embodiment, the motor comprises four substantially flat stators in stacked relationship, with pairs of the stators axially spaced, each of the stators comprising a tape-wound stator coil, and first and second substantially flat rotors disposed between the spaced pairs of stators. Each of the rotors includes an annular array of permanent magnets embedded therein. A first shaft is connected to the first rotor and a second, concentric shaft is connected to the second rotor, and a drive unit causes rotation of the two shafts in opposite directions. The second shaft comprises a hollow tube having a central bore in which the first shaft is disposed. Two different sets of bearings support the first and second shafts. In another embodiment, the motor comprises two ironless stators and pairs of rotors mounted on opposite sides of the stators and driven by counterrotating shafts.

Hawsey, Robert A. (Oak Ridge, TN); Bailey, J. Milton (Knoxville, TN)

1992-01-01T23:59:59.000Z

254

depleted underground oil shale for the permanent storage of carbon  

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

depleted underground oil shale for the permanent storage of carbon depleted underground oil shale for the permanent storage of carbon dioxide (CO 2 ) generated during the oil shale extraction process. AMSO, which holds a research, development, and demonstration (RD&D) lease from the U.S. Bureau of Land Management for a 160-acre parcel of Federal land in northwest Colorado's oil-shale rich Piceance Basin, will provide technical assistance and oil shale core samples. If AMSO can demonstrate an economically viable and environmentally acceptable extraction process, it retains the right to acquire a 5,120-acre commercial lease. When subject to high temperatures and high pressures, oil shale (a sedimentary rock that is rich in hydrocarbons) can be converted into oil. Through mineralization, the CO 2 could be stored in the shale

255

Hanford Permanent Isolation Barrier Program: Asphalt technology test plan  

SciTech Connect

The Hanford Permanent Isolation Barriers use engineered layers of natural materials to create an integrated structure with backup protective features. The objective of current designs is to develop a maintenance-free permanent barrier that isolates wastes for a minimum of 1000 years by limiting water drainage to near-zero amounts. Asphalt is being used as an impermeable water diversion layer to provide a redundant layer within the overall barrier design. Data on asphalt barrier properties in a buried environment are not available for the required 100-year time frame. The purpose of this test plan is to outline the activities planned to obtain data with which to estimate performance of the asphalt layers.

Freeman, H.D.; Romine, R.A.

1994-05-01T23:59:59.000Z

256

Experiences with permanent magnets at the Fermilab recycler ring  

E-Print Network (OSTI)

In order to achieve higher luminosities in Run II a separate antiproton storage ring was built in the Main Injector tunnel. To reduce both construction and operations costs permanent magnets were used. This paper discusses the design criterion and specifications, including temperature dependence, longitudinal uniformity, and adjusting of the higher harmonics of the magnets. The design tolerances for a storage ring are more stringent than for a single pass beam line. The difference between the measured and ideal central field for each magnet was held to better than 0.1%. The temperature stability for all magnets was set to better than 0.01% per degree Celsius. Higher order harmonics relative to the central field were set to less than 0.01%. This was done for all 484 permanent magnet that were built.

Volk, James T

2012-01-01T23:59:59.000Z

257

System Cost Analysis for an Interior Permanent Magnet Motor  

DOE Green Energy (OSTI)

The objective of this program is to provide an assessment of the cost structure for an interior permanent magnet ('IPM') motor which is designed to meet the 2010 FreedomCAR specification. The program is to evaluate the range of viable permanent magnet materials for an IPM motor, including sintered and bonded grades of rare earth magnets. The study considers the benefits of key processing steps, alternative magnet shapes and their assembly methods into the rotor (including magnetization), and any mechanical stress or temperature limits. The motor's costs are estimated for an annual production quantity of 200,000 units, and are broken out into such major components as magnetic raw materials, processing and manufacturing. But this is essentially a feasibility study of the motor's electromagnetic design, and is not intended to include mechanical or thermal studies as would be done to work up a selected design for production.

Peter Campbell

2008-08-01T23:59:59.000Z

258

Permanent magnet machine with windings having strand transposition  

DOE Patents (OSTI)

This document discusses, among other things, a stator with transposition between the windings or coils. The coils are free from transposition to increase the fill factor of the stator slots. The transposition at the end connections between an inner coil and an outer coil provide transposition to reduce circulating current loss. The increased fill factor reduces further current losses. Such a stator is used in a dual rotor, permanent magnet machine, for example, in a compressor pump, wind turbine gearbox, wind turbine rotor.

Qu, Ronghai (Clifton Park, NY); Jansen, Patrick Lee (Scotia, NY)

2009-04-21T23:59:59.000Z

259

Summary of radiation damage studies on rare earth permanent magnets  

SciTech Connect

With the proposed use of permanent magnets for both the NLC and the VLHC the issue flux loss due to radiation damage needs to be fully understood. There exist many papers on the subject. There are many difficulties in drawing conclusions from all of these data. First there is the difference methods of dosimetry, second different types of magnets and magnetic arrangements, and third different manufacturers of magnet material. This paper provides a summary of the existing literature on the subject.

J. T. Volk

2002-11-19T23:59:59.000Z

260

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

Note: This page contains sample records for the topic "variable speed permanent" 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

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

262

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

263

High speed drilling research advances  

Science Conference Proceedings (OSTI)

This article reports that the Amoco Production Company's Tulsa Research Center is developing a High Speed Drilling System (HSDS) to improve drilling economics for both exploration and development wells. The system is targeted for areas where historically the drilling rate is less than 25 ft/hr over a large section of hole. Designed as a five-year development program, work began on the system in late 1984. A major service company is participating in the project. The objective of the HSDS project is to improve drilling efficiency by developing improvements in the basic mechanical drilling system. The HSDS approach to improved drilling economics is via the traditional routes of increasing penetration rate (ROP) and bit life, increasing hole stability and reducing trouble time.

Warren, T.M.; Canson, B.E.

1987-03-01T23:59:59.000Z

264

High speed sampler and demultiplexer  

DOE Patents (OSTI)

A high speed sampling demultiplexer based on a plurality of sampler banks, each bank comprising a sample transmission line for transmitting an input signal, a strobe transmission line for transmitting a strobe signal, and a plurality of sampling gates at respective positions along the sample transmission line for sampling the input signal in response to the strobe signal. Strobe control circuitry is coupled to the plurality of banks, and supplies a sequence of bank strobe signals to the strobe transmission lines in each of the plurality of banks, and includes circuits for controlling the timing of the bank strobe signals among the banks of samplers. Input circuitry is included for supplying the input signal to be sampled to the plurality of sample transmission lines in the respective banks. The strobe control circuitry can repetitively strobe the plurality of banks of samplers such that the banks of samplers are cycled to create a long sample length. Second tier demultiplexing circuitry is coupled to each of the samplers in the plurality of banks. The second tier demultiplexing circuitry senses the sample taken by the corresponding sampler each time the bank in which the sampler is found is strobed. A plurality of such samples can be stored by the second tier demultiplexing circuitry for later processing. Repetitive sampling with the high speed transient sampler induces an effect known as ``strobe kickout``. The sample transmission lines include structures which reduce strobe kickout to acceptable levels, generally 60 dB below the signal, by absorbing the kickout pulses before the next sampling repetition. 16 figs.

McEwan, T.E.

1995-12-26T23:59:59.000Z

265

High speed sampler and demultiplexer  

DOE Patents (OSTI)

A high speed sampling demultiplexer based on a plurality of sampler banks, each bank comprising a sample transmission line for transmitting an input signal, a strobe transmission line for transmitting a strobe signal, and a plurality of sampling gates at respective positions along the sample transmission line for sampling the input signal in response to the strobe signal. Strobe control circuitry is coupled to the plurality of banks, and supplies a sequence of bank strobe signals to the strobe transmission lines in each of the plurality of banks, and includes circuits for controlling the timing of the bank strobe signals among the banks of samplers. Input circuitry is included for supplying the input signal to be sampled to the plurality of sample transmission lines in the respective banks. The strobe control circuitry can repetitively strobe the plurality of banks of samplers such that the banks of samplers are cycled to create a long sample length. Second tier demultiplexing circuitry is coupled to each of the samplers in the plurality of banks. The second tier demultiplexing circuitry senses the sample taken by the corresponding sampler each time the bank in which the sampler is found is strobed. A plurality of such samples can be stored by the second tier demultiplexing circuitry for later processing. Repetitive sampling with the high speed transient sampler induces an effect known as "strobe kickout". The sample transmission lines include structures which reduce strobe kickout to acceptable levels, generally 60 dB below the signal, by absorbing the kickout pulses before the next sampling repetition.

McEwan, Thomas E. (Livermore, CA)

1995-01-01T23:59:59.000Z

266

High-Energy Composite Permanent Magnets: High-Energy Permanent Magnets for Hybrid Vehicles and Alternative Energy  

SciTech Connect

Broad Funding Opportunity Announcement Project: The University of Delaware is developing permanent magnets that contain less rare earth material and produce twice the energy of the strongest rare earth magnets currently available. The University of Delaware is creating these magnets by mixing existing permanent magnet materials with those that are more abundant, like iron. Both materials are first prepared in the form of nanoparticles via techniques ranging from wet chemistry to ball milling. After that, the nanoparticles must be assembled in a 3-D array and consolidated at low temperatures to form a magnet. With small size particles and good contact between these two materials, the best qualities of each allow for the development of exceptionally strong composite magnets.

None

2010-02-15T23:59:59.000Z

267

Active control system for high speed windmills  

DOE Patents (OSTI)

A pump stroke is matched to the operating speed of a high speed windmill. The windmill drives a hydraulic pump for a control. Changes in speed of a wind driven shaft open supply and exhaust valves to opposite ends of a hydraulic actuator to lengthen and shorten an oscillating arm thereby lengthening and shortening the stroke of an output pump. Diminishing wind to a stall speed causes the valves to operate the hydraulic cylinder to shorten the oscillating arm to zero. A pressure accumulator in the hydraulic system provides the force necessary to supply the hydraulic fluid under pressure to drive the actuator into and out of the zero position in response to the windmill shaft speed approaching and exceeding windmill stall speed. 4 figs.

Avery, D.E.

1988-01-12T23:59:59.000Z

268

Active control system for high speed windmills  

DOE Patents (OSTI)

A pump stroke is matched to the operating speed of a high speed windmill. The windmill drives a hydraulic pump for a control. Changes in speed of a wind driven shaft open supply and exhaust valves to opposite ends of a hydraulic actuator to lengthen and shorten an oscillating arm thereby lengthening and shortening the stroke of an output pump. Diminishing wind to a stall speed causes the valves to operate the hydraulic cylinder to shorten the oscillating arm to zero. A pressure accumulator in the hydraulic system provides the force necessary to supply the hydraulic fluid under pressure to drive the actuator into and out of the zero position in response to the windmill shaft speed approaching and exceeding windmill stall speed.

Avery, Don E. (45-437 Akimala St., Honolulu, HI 96744)

1988-01-01T23:59:59.000Z

269

New Quantum Key System Combines Speed, Distance  

Science Conference Proceedings (OSTI)

... a prototype high-speed quantum key distribution (QKD) system ... a theoretically unbreakable “one-time pad” encryption, transmission and decryption ...

2013-07-08T23:59:59.000Z

270

'Dead Time' Limits Quantum Cryptography Speeds  

Science Conference Proceedings (OSTI)

... Not only does dead time limit the transmission rate of a message ... effects and paralyzability in high-speed quantum key distribution, New Journal of ...

2012-06-08T23:59:59.000Z

271

Microorganisms to Speed Production of Biofuels  

ORNL 2011-G00203/jcn UT-B ID 201002408 08.2011 Microorganisms to Speed Production of Biofuels Technology Summary Researchers at ORNL developed microorganisms that can ...

272

Optimization Online - Processor Speed Control with Thermal ...  

E-Print Network (OSTI)

Sep 29, 2007 ... Processor Speed Control with Thermal Constraints. Almir Mutapcic(almirm ***at** * stanford.edu) Stephen Boyd(boyd ***at*** stanford.edu)

273

Fluid Metrology Calibration Services - Air Speed  

Science Conference Proceedings (OSTI)

... National Institute of Standards and Technology provides calibration services for air speed instrumentation such as Pitot tubes, hot-wire or thermal ...

2013-02-11T23:59:59.000Z

274

Midwest High-Speed Rail Supply Chain  

Science Conference Proceedings (OSTI)

... Amtrak is also in the midst of a multi-year purchase. American manufacturing gets a boost from high-speed rail investment. ...

2013-03-08T23:59:59.000Z

275

Light Speed Invariance is a Remarkable Illusion  

E-Print Network (OSTI)

Though many experiments appear to have confirmed the light speed invariance postulate of special relativity theory, this postulate is actually unverified. This paper resolves this issue by first showing the manner in which an illusion of light speed invariance occurs in two-way light speed measurement in the framework of a semi-classical absolute space theory. It then demonstrates a measurable variation of the one-way speed of light, which directly invalidates the invariance postulate and confirms the existence of the preferred reference frame of the absolute space theory.

Stephan J. G. Gift

2007-08-20T23:59:59.000Z

276

Building Technologies Office: Speed and Scale  

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

Presentations from Track B, Speed and Scale, were presented in the following sessions: Audit Procedures Business Models (Session 1) Communication and Outreach Community Evaluation...

277

PHYSICS 359 THE SPEED OF LIGHT  

E-Print Network (OSTI)

in this experiment using a high speed light emitting diode (LED) modulated at 40 MHz as the source, and a PIN

Landstreet, John D.

278

High speed imager test station  

DOE Patents (OSTI)

A test station enables the performance of a solid state imager (herein called a focal plane array or FPA) to be determined at high image frame rates. A programmable waveform generator is adapted to generate clock pulses at determinable rates for clock light-induced charges from a FPA. The FPA is mounted on an imager header board for placing the imager in operable proximity to level shifters for receiving the clock pulses and outputting pulses effective to clock charge from the pixels forming the FPA. Each of the clock level shifters is driven by leading and trailing edge portions of the clock pulses to reduce power dissipation in the FPA. Analog circuits receive output charge pulses clocked from the FPA pixels. The analog circuits condition the charge pulses to cancel noise in the pulses and to determine and hold a peak value of the charge for digitizing. A high speed digitizer receives the peak signal value and outputs a digital representation of each one of the charge pulses. A video system then displays an image associated with the digital representation of the output charge pulses clocked from the FPA. In one embodiment, the FPA image is formatted to a standard video format for display on conventional video equipment. 12 figs.

Yates, G.J.; Albright, K.L.; Turko, B.T.

1995-11-14T23:59:59.000Z

279

High speed imager test station  

DOE Patents (OSTI)

A test station enables the performance of a solid state imager (herein called a focal plane array or FPA) to be determined at high image frame rates. A programmable waveform generator is adapted to generate clock pulses at determinable rates for clock light-induced charges from a FPA. The FPA is mounted on an imager header board for placing the imager in operable proximity to level shifters for receiving the clock pulses and outputting pulses effective to clock charge from the pixels forming the FPA. Each of the clock level shifters is driven by leading and trailing edge portions of the clock pulses to reduce power dissipation in the FPA. Analog circuits receive output charge pulses clocked from the FPA pixels. The analog circuits condition the charge pulses to cancel noise in the pulses and to determine and hold a peak value of the charge for digitizing. A high speed digitizer receives the peak signal value and outputs a digital representation of each one of the charge pulses. A video system then displays an image associated with the digital representation of the output charge pulses clocked from the FPA. In one embodiment, the FPA image is formatted to a standard video format for display on conventional video equipment.

Yates, George J. (Santa Fe, NM); Albright, Kevin L. (Los Alamos, NM); Turko, Bojan T. (Moraga, CA)

1995-01-01T23:59:59.000Z

280

Permanent magnet assisted synchronous reluctance motor, design and performance improvement  

E-Print Network (OSTI)

Recently, permanent magnet assisted (PMa)-synchronous reluctance motors (SynRM) have been considered as a possible alternative motor drive for high performance applications. In order to have an efficient motor drive, performing of three steps in design of the overall drive is not avoidable. These steps are design optimization of the motor, identification of the motor parameter and implementation of an advanced control system to ensure optimum operation. Therefore, this dissertation first deals with the design optimization of the Permanent Magnet Assisted Synchronous Reluctance Motor (PMa-SynRM). Various key points in the rotor design of a low cost PMa-SynRM are introduced and their effects are studied. Finite element approach has been utilized to show the effects of these parameters on the developed average electromagnetic torque and the total d-q inductances. As it can be inferred from the name of the motor, there are some permanent magnets mounted in the rotor core. One of the features considered in the design of this motor is the magnetization of the permanent magnets mounted in the rotor core using the stator windings to reduce the manufacturing cost. At the next step, identification of the motor parameters is discussed. Variation of motor parameters due to temperature and airgap flux has been reported in the literatures. Use of off-line models for estimating the motor parameters is known as a computationally intensive method, especially when the models include the effect of cross saturation. Therefore in practical applications, on-line parameter estimation is favored to achieve a high performance control system. In this dissertation, a simple practical method for parameter estimation of the PMa-SynRM is introduced. Last part of the dissertation presents one advanced control strategy which utilized the introduced parameter estimator. A practical Maximum Torque Per Ampere (MTPA) control scheme along with a simple parameter estimator for PMa-SynRM is introduced. This method is capable of maintaining the MTPA condition and stays robust against the variations of motor parameters. Effectiveness of the motor design procedure and the control strategy is validated by presenting simulation and experimental results of a 1.5 kW prototype PMa-SynRM, designed and manufactured through the introduced design method.

Niazi, Peyman

2005-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "variable speed permanent" 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

Superfast Search Engine Speeds Past the Competition | U.S. DOE Office of Science (SC)  

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

Superfast Search Engine Speeds Past the Competition Superfast Search Engine Speeds Past the Competition Stories of Discovery & Innovation Superfast Search Engine Speeds Past the Competition Enlarge Photo Getty Images Bitmap indices translate variable values into strings of bits, or 1's and 0's. These indices tend to be very efficient because computer processors are optimized to perform so-called logical operations on bits. Enlarge Photo Illustration: A. Tovey Source: Wu, Otto, and 05.31.11 Superfast Search Engine Speeds Past the Competition Software developed for analyzing physics data finds powerful commercial applications. Our world is increasingly data-driven, whether we are searching for information on our home computer, accessing databases for everything from medical records to financial data, or scanning the depths of outer

282

High-speed buffer management for 40 Gb/s-based photonic packet switches  

Science Conference Proceedings (OSTI)

We develop a method of high-speed buffer management for output-buffered photonic packet switches. The use of optical fiber delay lines is a promising solution to constructing optical buffers. The buffer manager determines packet delays in the fiber delay ... Keywords: buffer management, parallel processing, photonic packet switching, pipeline processing, variable-length optical packet

Hiroaki Harai; Masayuki Murata

2006-02-01T23:59:59.000Z

283

Copyright 2007 by ASME1 Laminar Flame Speeds and Strain Sensitivities of Mixtures of H2  

E-Print Network (OSTI)

to rich. [Keywords: Syngas, laminar flame speed, reactant preheat, CO2 dilution, N2 dilution] INTRODUCTION emissions. Synthetic gas (syngas) fuels derived from coal are particularly promising in this regard. Syngas, provides a significant barrier to syngas usage. Understanding the impact of this variability on combustor

Seitzman, Jerry M.

284

Variable ratio regenerative braking device  

DOE Patents (OSTI)

Disclosed is a regenerative braking device (10) for an automotive vehicle. The device includes an energy storage assembly (12) having a plurality of rubber rollers (26, 28) mounted for rotation between an input shaft (36) and an output shaft (42), clutches (38, 46) and brakes (40, 48) associated with each shaft, and a continuously variable transmission (22) connectable to a vehicle drivetrain and to the input and output shafts by the respective clutches. The rubber rollers are torsionally stressed to accumulate energy from the vehicle when the input shaft is clutched to the transmission while the brake on the output shaft is applied, and are torsionally relaxed to deliver energy to the vehicle when the output shaft is clutched to the transmission while the brake on the input shaft is applied. The transmission ratio is varied to control the rate of energy accumulation and delivery for a given rotational speed of the vehicle drivetrain.

Hoppie, Lyle O. (Birmingham, MI)

1981-12-15T23:59:59.000Z

285

Brushed permanent magnet DC MLC motor operation in an external magnetic field  

SciTech Connect

Purpose: Linac-MR systems for real-time image-guided radiotherapy will utilize the multileaf collimators (MLCs) to perform conformal radiotherapy and tumor tracking. The MLCs would be exposed to the external fringe magnetic fields of the linac-MR hybrid systems. Therefore, an experimental investigation of the effect of an external magnetic field on the brushed permanent magnet DC motors used in some MLC systems was performed. Methods: The changes in motor speed and current were measured for varying external magnetic field strengths up to 2000 G generated by an EEV electromagnet. These changes in motor characteristics were measured for three orientations of the motor in the external magnetic field, mimicking changes in motor orientations due to installation and/or collimator rotations. In addition, the functionality of the associated magnetic motor encoder was tested. The tested motors are used with the Varian 120 leaf Millennium MLC (Maxon Motor half leaf and full leaf motors) and the Varian 52 leaf MKII MLC (MicroMo Electronics leaf motor) including a carriage motor (MicroMo Electronics). Results: In most cases, the magnetic encoder of the motors failed prior to any damage to the gearbox or the permanent magnet motor itself. This sets an upper limit of the external magnetic field strength on the motor function. The measured limits of the external magnetic fields were found to vary by the motor type. The leaf motor used with a Varian 52 leaf MKII MLC system tolerated up to 450{+-}10 G. The carriage motor tolerated up to 2000{+-}10 G field. The motors used with the Varian 120 leaf Millennium MLC system were found to tolerate a maximum of 600{+-}10 G. Conclusions: The current Varian MLC system motors can be used for real-time image-guided radiotherapy coupled to a linac-MR system, provided the fringe magnetic fields at their locations are below the determined tolerance levels. With the fringe magnetic fields of linac-MR systems expected to be larger than the tolerance levels determined, some form of magnetic shielding would be required.

Yun, J.; St Aubin, J.; Rathee, S.; Fallone, B. G. [Department of Physics, University of Alberta, 11322-89 Avenue, Edmonton, Alberta T6G 2G7 (Canada) and Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada) and Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Department of Physics, University of Alberta, 11322-89 Avenue, Edmonton, Alberta T6G 2G7 (Canada); Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada) and Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada)

2010-05-15T23:59:59.000Z

286

Hanford Permanent Isolation Barrier Program: Asphalt technology development  

SciTech Connect

An important component of the Hanford Permanent Isolation Barrier is the use of a two-layer composite asphalt system, which provides backup water diversion capabilities if the primary capillary barrier fails to meet infiltration goals. Because of asphalt`s potential to perform to specification over the 1000-year design life criterion, a composite asphalt barrier (HMAC/fluid-applied polymer-modified asphalt) is being considered as an alternative to the bentonite clay/high density poly(ethylene) barriers for the low-permeability component of the Hanford Permanent Isolation Barrier. The feasibility of using asphalt as a long-term barrier is currently being studied. Information that must be known is the ability of asphalt to retain desirable physical properties over a period of 1000 years. This paper presents the approach for performing accelerated aging tests and evaluating the performance of samples under accelerated conditions. The results of these tests will be compared with asphalt artifact analogs and the results of modeling the degradation of the selected asphalt composite to make life-cycle predictions.

Freeman, H.D.; Romine, R.A.

1994-11-01T23:59:59.000Z

287

Adjustable permanent quadrupoles for the next linear collider  

Science Conference Proceedings (OSTI)

The proposed Next Linear Collider (NLC) will require over 1400 adjustable quadrupoles between the main linacs' accelerator structures. These 12.7 mm bore quadrupoles will have a range of integrated strength from 0.6 to 138 Tesla, with a maximum gradient of 141 Tesla per meter, an adjustment range of +0 to {minus}20% and effective lengths from 324 mm to 972 mm. The magnetic center must remain stable to within 1 micron during the 20% adjustment. In an effort to reduce costs and increase reliability, several designs using hybrid permanent magnets have been developed. Four different prototypes have been built. All magnets have iron poles and use Samarium Cobalt to provide the magnetic fields. Two use rotating permanent magnetic material to vary the gradient, one uses a sliding shunt to vary the gradient and the fourth uses counter rotating magnets. Preliminary data on gradient strength, temperature stability, and magnetic center position stability are presented. These data are compared to an equivalent electromagnetic prototype.

James T. Volk et al.

2001-06-22T23:59:59.000Z

288

Interior Permanent Magnet Reluctance Machine with Brushless Field Excitation  

SciTech Connect

In a conventional permanent magnet (PM) machine, the air-gap flux produced by the PM is fixed. It is difficult to enhance the air-gap flux density due to limitations of the PM in a series-magnetic circuit. However, the air-gap flux density can be weakened by using power electronic field weakening to the limit of demagnetization of the PMs. This paper presents the test results of controlling the PM air-gap flux density through the use of a stationary brushless excitation coil in a reluctance interior permanent magnet with brushless field excitation (RIPM-BFE) motor. Through the use of this technology the air-gap flux density can be either enhanced or weakened. There is no concern with demagnetizing the PMs during field weakening. The leakage flux of the excitation coil through the PMs is blocked. The prototype motor built on this principle confirms the concept of flux enhancement and weakening through the use of excitation coils.

Wiles, R.H.

2005-10-07T23:59:59.000Z

289

Study of Various Slanted Air-Gap Structures of Interior Permanent Magnet Synchronous Motor with Brushless Field Excitation  

SciTech Connect

This paper shows how to maximize the effect of the slanted air-gap structure of an interior permanent magnet synchronous motor with brushless field excitation (BFE) for application in a hybrid electric vehicle. The BFE structure offers high torque density at low speed and weakened flux at high speed. The unique slanted air-gap is intended to increase the output torque of the machine as well as to maximize the ratio of the back-emf of a machine that is controllable by BFE. This irregularly shaped air-gap makes a flux barrier along the d-axis flux path and decreases the d-axis inductance; as a result, the reluctance torque of the machine is much higher than a uniform air-gap machine, and so is the output torque. Also, the machine achieves a higher ratio of the magnitude of controllable back-emf. The determination of the slanted shape was performed by using magnetic equivalent circuit analysis and finite element analysis (FEA).

Tolbert, Leon M [ORNL; Lee, Seong T [ORNL

2010-01-01T23:59:59.000Z

290

Analysis of Slanted Air-gap Structure of Interior Permanent Magnet Synchronous Motor with Brushless Field Excitation  

E-Print Network (OSTI)

Analysis of Slanted Air-gap Structure of Interior Permanent Magnet Synchronous Motor with Brushless permanent magnet synchronous motor (IPMSM) for application in a hybrid electric vehicle. This unique slanted permanent magnet synchronous motor FEA finite element analysis PM permanent magnet II. INTRODUCTION

Tolbert, Leon M.

291

Study on Matching Strategies and Simulation of Hydro-mechanical Continuously Variable Transmission System of Tractor  

Science Conference Proceedings (OSTI)

In this paper, the engine output torque model and fuel consumption model are established based on engine test results. The engine rotary speed feature denotes the relationship between the engine rotary speed and the throttle opening when engine works ... Keywords: Tractor, Hydro-mechanical continuously variable transmission, Matching strategies, Simulation

Xu Liyou; Zhou Zhili; Cao Qingmei; Zhang Mingzhu

2010-05-01T23:59:59.000Z

292

Pitch angle control in wind turbines above the rated wind speed by multi-layer perceptron and radial basis function neural networks  

Science Conference Proceedings (OSTI)

In wind energy conversion systems, one of the operational problems is the changeability and discontinuity of wind. In most cases, wind speed can fluctuate rapidly. Hence, quality of produced energy becomes an important problem in wind energy conversion ... Keywords: Neural network-based controller, Pitch control, Variable-speed wind turbine, Wind energy conversion systems

Ahmet Serdar Yilmaz; Zafer Özer

2009-08-01T23:59:59.000Z

293

Performance of An Adjustable Strength Permanent Magnet Quadrupole  

SciTech Connect

An adjustable strength permanent magnet quadrupole suitable for use in Next Linear Collider has been built and tested. The pole length is 42cm, aperture diameter 13mm, peak pole tip strength 1.03Tesla and peak integrated gradient * length (GL) is 68.7 Tesla. This paper describes measurements of strength, magnetic CL and field quality made using an air bearing rotating coil system. The magnetic CL stability during -20% strength adjustment proposed for beam based alignment was < 0.2 microns. Strength hysteresis was negligible. Thermal expansion of quadrupole and measurement parts caused a repeatable and easily compensated change in the vertical magnetic CL. Calibration procedures as well as CL measurements made over a wider tuning range of 100% to 20% in strength useful for a wide range of applications will be described. The impact of eddy currents in the steel poles on the magnetic field during strength adjustments will be reported.

Gottschalk, S.C.; DeHart, T.E.; Kangas, K.W.; /STI Optronics, Bellevue; Spencer, C.M.; /SLAC; Volk, J.T.; /Fermilab

2006-03-01T23:59:59.000Z

294

Electron current extraction from a permanent magnet waveguide plasma cathode  

SciTech Connect

An electron cyclotron resonance plasma produced in a cylindrical waveguide with external permanent magnets was investigated as a possible plasma cathode electron source. The configuration is desirable in that it eliminates the need for a physical antenna inserted into the plasma, the erosion of which limits operating lifetime. Plasma bulk density was found to be overdense in the source. Extraction currents over 4 A were achieved with the device. Measurements of extracted electron currents were similar to calculated currents, which were estimated using Langmuir probe measurements at the plasma cathode orifice and along the length of the external plume. The influence of facility effects and trace ionization in the anode-cathode gap are also discussed.

Weatherford, B. R.; Foster, J. E. [University of Michigan, Ann Arbor, Michigan 48109 (United States); Kamhawi, H. [NASA Glenn Research Center, Cleveland, Ohio 44135 (United States)

2011-09-15T23:59:59.000Z

295

Modeling And Analysis of Radial Flux Toroidally Wound Twin Rotor Permanent Magnet Motor.  

E-Print Network (OSTI)

??The main objective of current thesis is the study of Radial Flux Twin Rotor Permanent Magnet (RFTWTRPM) motor. The tasks were to review the literature… (more)

Pratapa, Ravi Kishore

2010-01-01T23:59:59.000Z

296

Initial rotor position estimation for low saliency interior permanent-magnet synchronous motor drives.  

E-Print Network (OSTI)

??This work presents an initial rotor position estimation method for low saliency interior permanent-magnet synchronous motor (IPMSM) drives. The method injects signals into the stationary… (more)

Yang, Yan.

2010-01-01T23:59:59.000Z

297

Design of a Ferrite Permanent Magnet Rotor for a Wind Power Generator.  

E-Print Network (OSTI)

?? Due to the insecurity of the supply of raw materials needed for neodymium-iron-boron magnets, typically used in permanent magnet generators, the use of ferrite… (more)

Eklund, Petter

2013-01-01T23:59:59.000Z

298

Study on Performance Characteristics of Interior Permanent Magnet Synchronous Motor Due to Rotor Configuration.  

E-Print Network (OSTI)

??This research study was conducted in an effort to understand what effects the rotor configuration has on the performance of a permanent magnet synchronous machine,… (more)

Kettlewell, James

2013-01-01T23:59:59.000Z

299

Dynamic high pressure process for fabricating superconducting and permanent magnetic materials  

DOE Patents (OSTI)

Shock waves directed on thin layers of materials is used to form superconducting and permanent magnetic materials with improved microstructures. 9 figs.

Nellis, W.J.; Maple, M.B.; Geballe, T.H.

1986-12-04T23:59:59.000Z

300

A dual-channel flux-switching permanent magnet motor for hybrid electric vehicles  

Science Conference Proceedings (OSTI)

The flux-switching permanent magnet (FSPM) motor is a relatively novel brushless machine having both magnets and concentrated windings in the stator

Wei Hua; Zhongze Wu; Ming Cheng; Baoan Wang; Jianzhong Zhang; Shigui Zhou

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "variable speed permanent" 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

Speeding Up Zeolite Evaluation for Carbon Capture  

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

Speeding Up Speeding Up Zeolite Evaluation for Carbon Capture Speeding Up Zeolite Evaluation for Carbon Capture Zeolite.png Schematic of an important class of porous materials known as zeolites. The large red structure in the center of this periodic structure is a cavity that might be a good candidate for adsorption of a gas such as carbon dioxide. The seven small red areas at the corners (plus the one hidden by the yellow ball) are not suitable and need to be eliminated from studies that attempt to predict guest-related properties using molecular simulation techniques. A new method developed at NERSC uses software to differentiate between suitable and unsuitable pockets, thereby speeding up discovery of new materials. Why it Matters: Capturing and sequestering waste carbon dioxide (CO2) is a

302

High-Speed Rail Comes to London  

E-Print Network (OSTI)

airlines have invested in rail? ? A C C E S S NUMBER 19,struction of the Channel Tunnel Rail Link, Stage Two—the UK’of a debate about high-speed rail transportation, spurred by

Hall, Sir Peter

2001-01-01T23:59:59.000Z

303

The invariance of the speed of light  

E-Print Network (OSTI)

We show that the conclusion of a recent experiment [arXiv:0912.3934] that claims to have discovered that "the speed of light seems to depend on the motion of the observer" is wrong.

Jerrold Franklin

2010-02-21T23:59:59.000Z

304

Quantifying hurricane wind speed with undersea sound  

E-Print Network (OSTI)

Hurricanes, powerful storms with wind speeds that can exceed 80 m/s, are one of the most destructive natural disasters known to man. While current satellite technology has made it possible to effectively detect and track ...

Wilson, Joshua David

2006-01-01T23:59:59.000Z

305

Capacity-Speed Relationships in Prefrontal Cortex  

E-Print Network (OSTI)

Working memory (WM) capacity and WM processing speed are simple cognitive measures that underlie human performance in complex processes such as reasoning and language comprehension. These cognitive measures have shown to ...

Prabhakaran, Vivek

306

The Autocorrelation of Hourly Wind Speed Observations  

Science Conference Proceedings (OSTI)

The autocorrelation of hourly wind speed observations is estimated for seven stations on the west coast of Canada at selected lags ranging from one hour to two months. The estimated autocorrelation function is fitted by a model that includes a ...

Arthur C. Brett; Stanton E. Tuller

1991-06-01T23:59:59.000Z

307

Makeup and uses of a basic magnet laboratory for characterizing high-temperature permanent magnets  

DOE Green Energy (OSTI)

A set of instrumentation for making basic magnetic measurements was assembled in order to characterize high-intrinsic-coercivity, rare-earth permanent magnets with respect to short-term demagnetization resistance and long-term aging at temperatures up to 300{degrees}C. The major specialized components of this set consist of a 13-T-peak-field, capacitor-discharge pulse magnetizer; a 10-in.-pole-size, variable-gap electromagnet; a temperature-controlled oven equipped with iron-cobalt pole piece extensions and a removable paddle that carries the magnetization and field sensing coils; associated electronic integrators; and standards for field intensity H and magnetic moment M calibration. A 1-cm cubic magnet sample, carried by the paddle, fits snugly between the pole piece extensions within the electrically heated aluminum oven, where fields up to 3.2 T can be applied by the electromagnet at temperatures up to 300{degrees}C. A sample set of demagnetization data for the high-energy Sm{sub 2}Co{sub 17} type of magnet is given for temperatures up to 300{degrees}C. These data are reduced to the temperature dependence of the M-H knee field and of the field for a given magnetic induction swing, and they are then interpreted to show the limits of safe magnet operation.

Niedra, J.M. [Sverdrup Technology, Inc., Brook Park, OH (United States). Lewis Research Center Group; Schwarze, G.E. [National Aeronautics and Space Administration, Cleveland, OH (United States). Lewis Research Center

1994-09-01T23:59:59.000Z

308

Combination of Speed Stroke Grinding and High Speed Grinding with Regard to Sustainability  

E-Print Network (OSTI)

Speed Grinding with Regard to Sustainability B. Linke 1 , M.for Manufacturing and Sustainability (LMAS) at UC Berkeley,leads to high process sustainability. Furthermore, lower

Linke, Barbara; M. Duscha; F. Klocke; Dornfeld, David

2011-01-01T23:59:59.000Z

309

Speeding Up Science Data Transfers Between Department of Energy...  

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

Speeding Up Science Data Transfers Between Department of Energy Facilities Speeding Up Science Data Transfers Between Department of Energy Facilities May 16, 2009 As scientists...

310

Carderock 2-ft Variable Pressure Cavitation Water Tunnel | Open Energy  

Open Energy Info (EERE)

2-ft Variable Pressure Cavitation Water Tunnel 2-ft Variable Pressure Cavitation Water Tunnel Jump to: navigation, search Basic Specifications Facility Name Carderock 2-ft Variable Pressure Cavitation Water Tunnel Overseeing Organization United States Naval Surface Warfare Center Hydrodynamic Testing Facility Type Tunnel Beam(m) 0.6 Depth(m) 0.6 Water Type Freshwater Cost(per day) Contact POC Special Physical Features The 2-Foot Variable Pressure Cavitation Water Tunnel is a vertical plane, closed recirculating, variable-speed, variable-pressure, open jet test section, closed jet test section, and semi-rectangular test section. Towing Capabilities Towing Capabilities None Wavemaking Capabilities Wavemaking Capabilities None Channel/Tunnel/Flume Channel/Tunnel/Flume Yes Velocity(m/s) 17 Recirculating Yes

311

Carderock 3-ft Variable Pressure Cavitation Water Tunnel | Open Energy  

Open Energy Info (EERE)

Variable Pressure Cavitation Water Tunnel Variable Pressure Cavitation Water Tunnel Jump to: navigation, search Basic Specifications Facility Name Carderock 3-ft Variable Pressure Cavitation Water Tunnel Overseeing Organization United States Naval Surface Warfare Center Hydrodynamic Testing Facility Type Tunnel Beam(m) 0.7 Depth(m) 0.7 Water Type Freshwater Cost(per day) Contact POC Special Physical Features The 3-ft Variable Pressure Cavitation Water Tunnel is a vertical plane, closed recirculating with resorber, variable-speed, variable-pressure, two interchangeable circular test sections. Towing Capabilities Towing Capabilities None Wavemaking Capabilities Wavemaking Capabilities None Channel/Tunnel/Flume Channel/Tunnel/Flume Yes Velocity(m/s) 25.8 Recirculating Yes Wind Capabilities Wind Capabilities None

312

Impact of Permanent Magnet Field on Inductance Variation of a PMLSM Julien Gomand1  

E-Print Network (OSTI)

of Surface Mounted Permanent Magnet Linear Synchronous Motors are generally presented with constantImpact of Permanent Magnet Field on Inductance Variation of a PMLSM Julien Gomand1 , Ghislain Remy1 Linear drive, Modelling, Estimation technique, Synchronous motor, Harmonics. Abstract Analytical models

Paris-Sud XI, Université de

313

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

314

COMPARAISON DES PERFORMANCES DE DEUX MOTEURS LECTRIQUES AUTOPILOTS : LE MOTEUR SYNCHRONE AIMANTS PERMANENTS  

E-Print Network (OSTI)

SELF COMMUTATED ELECTRIC MOTORS : THE PERMANENT MAGNET BRUSHLESS DC MOTOR THE SWITCHED RELUCTANCE MOTOR synchronous brushless motors. These motors are, on one hand, the permanent-magnet brushless DC motor supplied by quasi-square currents, with magnets mounted at rotor surface and trapezoidal e.m.f. waveform, and

Paris-Sud XI, Université de

315

Current Controller with Defined Dynamic Behavior for an Interior Permanent Magnet  

E-Print Network (OSTI)

Current Controller with Defined Dynamic Behavior for an Interior Permanent Magnet Synchronous Motor saturation and changing motor parameters. In this paper a current control scheme is presented that ensures combustion vehicles already provide. Today's modern HEV and EV mostly include interior permanent magnet

Noé, Reinhold

316

Optimum Control for Interior Permanent Magnet Synchronous Motors (IPMSM) in Constant  

E-Print Network (OSTI)

Optimum Control for Interior Permanent Magnet Synchronous Motors (IPMSM) in Constant Torque and Electrical Drives, Paderborn, Germany Abstract--Interior Permanent Magnet Synchronous Motors (IPMSM) gain weakening range. Operation during flux weakening, however, causes stress to the magnets of the motor

Noé, Reinhold

317

Modular Permanent Magnet Machine Based on Soft Magnetic *** Burgess-Norton Mfg.Co.  

E-Print Network (OSTI)

of surface permanent magnet motor, and [8] small induction motors. In this paper, novel single phase2005-30 Modular Permanent Magnet Machine Based on Soft Magnetic Composite *** Burgess-Norton Mfg magnetic composite (SMC) material, electric machine design is no longer limited to the traditional iron

Lipo, Thomas

318

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

319

Design and Analysis of a Nested Halbach Permanent Magnet Magnetic Refrigerator  

E-Print Network (OSTI)

Design and Analysis of a Nested Halbach Permanent Magnet Magnetic Refrigerator by Armando Tura BEng Committee Design and Analysis of a Nested Halbach Permanent Magnet Magnetic Refrigerator by Armando Tura with the potential to create efficient and compact refrigeration devices is an active magnetic regenerative

Victoria, University of

320

Optimal control in energy conversion of small wind power systems with permanent-magnet-synchronous-generators  

Science Conference Proceedings (OSTI)

This paper presents the results of experimental investigation of a low-power wind energy conversion system (WECS), based on a permanent-magnet synchronous generator (PMSG) connected directly to the turbine. A development system was built in order to ... Keywords: hardware-in-the-loop simulation, maximum power point tracking, optimal control, permanent-magnet synchronous generator, wind system

C. Vlad; I. Munteanu; A. I. Bratcu; E. Ceanga

2008-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "variable speed permanent" 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

Alternative Fuels Data Center: Low-Speed Vehicle Definition  

Alternative Fuels and Advanced Vehicles Data Center (EERE)

Low-Speed Vehicle Low-Speed Vehicle Definition to someone by E-mail Share Alternative Fuels Data Center: Low-Speed Vehicle Definition on Facebook Tweet about Alternative Fuels Data Center: Low-Speed Vehicle Definition on Twitter Bookmark Alternative Fuels Data Center: Low-Speed Vehicle Definition on Google Bookmark Alternative Fuels Data Center: Low-Speed Vehicle Definition on Delicious Rank Alternative Fuels Data Center: Low-Speed Vehicle Definition on Digg Find More places to share Alternative Fuels Data Center: Low-Speed Vehicle Definition on AddThis.com... More in this section... Federal State Advanced Search All Laws & Incentives Sorted by Type Low-Speed Vehicle Definition A low-speed vehicle is defined as a limited use automobile or truck that has a maximum speed greater than 20 miles per hour (mph) but not more than

322

Questions and Answers - Why is a non-permanent, but long lasting, magnet  

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

Which jobs use electromagnets? Which jobs use electromagnets? Previous Question (Which jobs use electromagnets?) Questions and Answers Main Index Next Question (Can you turn something into a magnet by banging on it in a specific way?) Can you turn something into a magnetby banging on it in a specific way? Why is a non-permanent, but long lasting, magnet called a permanent magnet? Permanent magnets are magnets that you don't have to use energy to make them magnetic. Some types of permanent magnets, relative to the length of lives of humans, are pretty close to permanent. They decay slowly, but they do decay. When most of the magnetic domains in a material align in one direction you can call that a magnet. It helps if you can imagine a magnet as being made up of a bunch of little magnets. Each one has tiny North and

323

Hybrid permanent magnet quadrupoles for the Recycler Ring at Fermilab  

Science Conference Proceedings (OSTI)

Hybrid Permanent Magnet Quadrupoles are used in several applications for the Fermilab Recycler Ring and associated beam transfer lines. Most of these magnets use a 0.6096 m long iron shell and provide integrated gradients up to 1.4 T-m/m with an iron pole tip radius of 41.6 mm. A 58.4 mm pole radius design is also required. Bricks of 25. 4 mm thick strontium ferrite supply the flux to the back of the pole to produce the desired gradients (0.6 to 2.75 T/m). For temperature compensation, Ni-Fe alloy strips are interspersed between ferrite bricks to subtract flux in a temperature dependent fashion. Adjustments of the permeance of each pole using iron between the pole and the flux return shell permits the matching of pole potentials. Magnetic potentials of the poles are adjusted to the desired value to achieve the prescribed strength and field uniformity based on rotating coil harmonic measurements. Procurement, fabrication, pole potential adjustment, and measured fields will be reported.

Brown, B.C.; Pruss, S.M.; Foster, G.W.; Glass, H.D.; Harding, D.J.; Jackson, G.R.; May, M.R.; Nicol, T.H.; Ostiguy, J.-F.; Schlabach, R.; Volk, J.T.

1997-10-01T23:59:59.000Z

324

MHL High Speed Cavitation | Open Energy Information  

Open Energy Info (EERE)

High Speed Cavitation High Speed Cavitation Jump to: navigation, search Basic Specifications Facility Name MHL High Speed Cavitation Overseeing Organization University of Michigan Hydrodynamics Hydrodynamic Testing Facility Type Channel Length(m) 0.8 Beam(m) 0.2 Depth(m) 0.2 Cost(per day) $2000(+ Labor/Materials) Towing Capabilities Towing Capabilities Yes Maximum Velocity(m/s) 25.9 Wavemaking Capabilities Wavemaking Capabilities None Channel/Tunnel/Flume Channel/Tunnel/Flume Yes Velocity(m/s) 25.9 Recirculating No Wind Capabilities Wind Capabilities None Control and Data Acquisition Description Custom Data Acquisition System using National Instruments hardware; system compatible with Planing Hull and Floating Beam Dynamometers Number of channels 16 Bandwidth(kHz) 20 Cameras Yes

325

Laminar flame speeds of moist syngas mixtures  

SciTech Connect

This work experimentally investigates the effect of the presence of water vapor on the laminar flame speeds of moist syngas/air mixtures using the counterflow twin-flame configuration. The experimental results presented here are for fuel lean syngas mixtures with molar percentage of hydrogen in the hydrogen and carbon monoxide mixture varying from 5% to 100%, for an unburned mixture temperature of 323 K, and under atmospheric pressure. At a given equivalence ratio, the effect of varying amount of water vapor addition on the measured laminar flame speed is demonstrated. The experimental laminar flame speeds are also compared with computed values using chemical kinetic mechanisms reported in the literature. It is found that laminar flame speed varies non-monotonically with addition of water for the carbon monoxide rich mixtures. It first increases with increasing amount of water addition, reaches a maximum value, and then decreases. An integrated reaction path analysis is further conducted to understand the controlling mechanism responsible for the non-monotonic variation in laminar flame speed due to water addition. On the other hand, for higher values of H{sub 2}/CO ratio the laminar flame speed monotonically decreases with increasing water addition. It is shown that the competition between the chemical and thermal effects of water addition leads to the observed response. Furthermore, reaction rate sensitivity analysis as well as binary diffusion coefficient sensitivity analysis are conducted to identify the possible sources of discrepancy between the experimental and predicted values. The sensitivity results indicate that the reaction rate constant of H{sub 2}+OH = H{sub 2}O+H is worth revisiting and refinement of binary diffusion coefficient data of N{sub 2}-H{sub 2}O, N{sub 2}-H{sub 2}, and H{sub 2}-H{sub 2}O pairs can be considered. (author)

Das, Apurba K. [Department of Mechanical and Aerospace Engineering, Case Western Reserve University, Cleveland, OH 44106 (United States); Kumar, Kamal; Sung, Chih-Jen [Department of Mechanical Engineering, University of Connecticut, Storrs, CT 06269 (United States)

2011-02-15T23:59:59.000Z

326

Centrifugal compressor surge and speed control  

E-Print Network (OSTI)

Abstract—Previous work on stabilization of compressor surge is extended to include control of the angular velocity of the compressor. First a low-order centrifugal compressor model is presented where the states are mass flow, pressure rise, and rotational speed of the spool. Energy transfer considerations are used to develop a compressor characteristic. In order to stabilize equilibria to the left of the surge line, a close coupled valve is used in series with the compressor. Controllers for the valve pressure drop and spool speed are derived. Semiglobal exponential stability is proved using a Lyapunov argument. Index Terms — Compressors, Lyapunov methods, modeling, surge control.

Jan Tommy Gravdahl; Olav Egel

1999-01-01T23:59:59.000Z

327

U.S. Building-Sector Energy Efficiency Potential  

E-Print Network (OSTI)

commutated permanent magnet motor, single-speed operationcommutated permanent magnet furnace-fan motor, single- speed

Brown, Rich

2008-01-01T23:59:59.000Z

328

Call Forwarding: New NIST Procedure Could Speed Cell ...  

Science Conference Proceedings (OSTI)

Call Forwarding: New NIST Procedure Could Speed Cell Phone Testing. For Immediate Release: March 2, 2010. ...

2010-10-05T23:59:59.000Z

329

NIST Measurement Advance Could Speed Innovation in Solar ...  

Science Conference Proceedings (OSTI)

NIST Measurement Advance Could Speed Innovation in Solar Devices. From NIST Tech Beat: July 25, 2012. ...

2012-07-25T23:59:59.000Z

330

Modelling and forecasting wind speed intensity for weather risk management  

Science Conference Proceedings (OSTI)

The main interest of the wind speed modelling is on the short-term forecast of wind speed intensity and direction. Recently, its relationship with electricity production by wind farms has been studied. In fact, electricity producers are interested in ... Keywords: ARFIMA-FIGARCH, Auto Regressive Gamma, Gamma Auto Regressive, Weather risk management, Wind speed modelling, Wind speed simulation

Massimiliano Caporin; Juliusz Pre

2012-11-01T23:59:59.000Z

331

VARIABLE TIME DELAY MEANS  

DOE Patents (OSTI)

An electrically variable time delay line is described which may be readily controlled simuitaneously with variable impedance matching means coupied thereto such that reflections are prevented. Broadly, the delay line includes a signal winding about a magnetic core whose permeability is electrically variable. Inasmuch as the inductance of the line varies directly with the permeability, the time delay and characteristic impedance of the line both vary as the square root of the permeability. Consequently, impedance matching means may be varied similariy and simultaneously w:th the electrically variable permeability to match the line impedance over the entire range of time delay whereby reflections are prevented.

Clemensen, R.E.

1959-11-01T23:59:59.000Z

332

Alternative Fuels Data Center: Limited Speed Vehicle Access to Roadways  

Alternative Fuels and Advanced Vehicles Data Center (EERE)

Limited Speed Vehicle Limited Speed Vehicle Access to Roadways to someone by E-mail Share Alternative Fuels Data Center: Limited Speed Vehicle Access to Roadways on Facebook Tweet about Alternative Fuels Data Center: Limited Speed Vehicle Access to Roadways on Twitter Bookmark Alternative Fuels Data Center: Limited Speed Vehicle Access to Roadways on Google Bookmark Alternative Fuels Data Center: Limited Speed Vehicle Access to Roadways on Delicious Rank Alternative Fuels Data Center: Limited Speed Vehicle Access to Roadways on Digg Find More places to share Alternative Fuels Data Center: Limited Speed Vehicle Access to Roadways on AddThis.com... More in this section... Federal State Advanced Search All Laws & Incentives Sorted by Type Limited Speed Vehicle Access to Roadways A limited speed vehicle is defined as a vehicle that is capable of

333

Alternative Fuels Data Center: Low-Speed Vehicle Inspection Exemption  

Alternative Fuels and Advanced Vehicles Data Center (EERE)

Low-Speed Vehicle Low-Speed Vehicle Inspection Exemption to someone by E-mail Share Alternative Fuels Data Center: Low-Speed Vehicle Inspection Exemption on Facebook Tweet about Alternative Fuels Data Center: Low-Speed Vehicle Inspection Exemption on Twitter Bookmark Alternative Fuels Data Center: Low-Speed Vehicle Inspection Exemption on Google Bookmark Alternative Fuels Data Center: Low-Speed Vehicle Inspection Exemption on Delicious Rank Alternative Fuels Data Center: Low-Speed Vehicle Inspection Exemption on Digg Find More places to share Alternative Fuels Data Center: Low-Speed Vehicle Inspection Exemption on AddThis.com... More in this section... Federal State Advanced Search All Laws & Incentives Sorted by Type Low-Speed Vehicle Inspection Exemption Low-speed vehicles are exempt from annual state vehicle inspections.

334

Detour : Los Angeles River Speed Cinema  

E-Print Network (OSTI)

We live in the culture of speed; everything is on its way to become a faster version of itself tomorrow if it is not already there today. Automobile and cinema are two inventions at the turn of the 20th Century that brought ...

Lee, Weifeng Victoria

2010-01-01T23:59:59.000Z

335

Airfoil shape for flight at subsonic speeds  

DOE Patents (OSTI)

An airfoil having an upper surface shaped to control flow accelerations and pressure distribution over the upper surface and to prevent separation of the boundary layer due to shock wave formulation at high subsonic speeds well above the critical Mach number. A highly cambered trailing edge section improves overall airfoil lifting efficiency.

Whitcomb, Richard T. (Hampton, VA)

1976-01-01T23:59:59.000Z

336

Control of Surface Mounted Permanent Magnet Motors with Special Application to Fractional-Slot Motors with Concentrated Windings  

SciTech Connect

A 30 pole, 6 kW, and 6000 maximum revolutions per minute (rpm) prototype of the permanent magnet synchronous motor (PMSM) with fractional-slot concentrated windings (FSCW) has been designed, built, and tested at the University of Wisconsin at Madison (UWM). This machine has significantly more inductance than that of regular PMSMs. The prototype was delivered in April 2006 to the Oak Ridge National Laboratory (ORNL) for testing and development of a controller that will achieve maximum efficiency. In advance of the test/control development effort, ORNL has used the PMSM models developed over a number of previous studies to study how steady state performance of high inductance PMSM machines relates to control issues. This report documents the results of this research. The amount of inductance that enables the motor to achieve infinite constant power speed ratio (CPSR) is given by L{sub {infinity}} = E{sub b}/{Omega}{sub b}I{sub R}, where E{sub b} is the root-mean square (rms) magnitude of the line-to-neutral back-electromotive force (emf) at base speed, {Omega}{sub b} is the base speed in electrical radians per second, and I{sub R} is the rms current rating of the motor windings. The prototype machine that was delivered to ORNL has about 1.5 times as much inductance as a typical PMSM with distributed integral slot windings. The inventors of the FSCW method, who designed the prototype machine, remarked that they were 'too successful' in incorporating inductance into their machine and that steps would be taken to modify the design methodology to reduce the inductance to the optimum value. This study shows a significant advantage of having the higher inductance rather than the optimal value because it enables the motor to develop the required power at lower current thereby reducing motor and inverter losses and improving efficiency. The main problem found with high inductance machines driven by a conventional phase advance (CPA) method is that the motor current at high speed depends solely on machine parameters and is virtually independent of the load level and the direct current (dc) supply voltage. Thus, the motor current is virtually the same at no load as at full load resulting in poor efficiency at less than full load conditions. While an inductance higher than the value cited above is warranted, it still does not ensure that the motor current is proportional to load; consequently, the problem of low efficiency at high speed and partial load is not resolved but is only mitigated. A common definition of 'base speed' is the speed at which the voltage applied to the motor armature is equal to the magnitude of the back-emf. The results in this study indicate that the dc supply voltage should be adequate to drive rated current into the motor winding at the specified base speed. At a minimum this requires sufficient voltage to overcome not only the back-emf but also the voltage drop across the internal impedance of the machine. For a high inductance PMSM, the internal impedance at base speed can be considerable and substantial additional voltage is required to overcome the internal voltage drop. It is further shown that even more voltage than the minimum required for injecting rated current at base speed can be beneficial by allowing the required power to be developed at lower current, which reduces losses in the motor and inverter components. Further, it is shown that the current is minimized at a unique speed; consequently, there may be room for optimization if the drive spends a substantial amount of its operating life at a certain speed (for example 60 mph). In this study, fundamental frequency phasor models are developed for a synchronous PMSM and the control systems that drive them is CPA. The models were compared with detailed simulations to show their validity. The result was used to design a traction drive control system with optimized efficiency to drive the fractional-slot motor with concentrated windings. The goal is to meet or exceed the FreedomCAR inverter cost and performance targets.

McKeever, John W [ORNL; Patil, Niranjan [University of Tennessee, Knoxville (UTK); Lawler, Jack [ORNL

2007-07-01T23:59:59.000Z

337

Control of Surface Mounted Permanent Magnet Motors with Special Application to Fractional-Slot Motors with Concentrated Windings  

SciTech Connect

A 30 pole, 6 kW, and 6000 maximum revolutions per minute (rpm) prototype of the permanent magnet synchronous motor (PMSM) with fractional-slot concentrated windings (FSCW) has been designed, built, and tested at the University of Wisconsin at Madison (UWM). This machine has significantly more inductance than that of regular PMSMs. The prototype was delivered in April 2006 to the Oak Ridge National Laboratory (ORNL) for testing and development of a controller that will achieve maximum efficiency. In advance of the test/control development effort, ORNL has used the PMSM models developed over a number of previous studies to study how steady state performance of high inductance PMSM machines relates to control issues. This report documents the results of this research. The amount of inductance that enables the motor to achieve infinite constant power speed ratio (CPSR) is given by L{sub {infinity}} = E{sub b}/{Omega}{sub b}I{sub R}, where E{sub b} is the root-mean square (rms) magnitude of the line-to-neutral back-electromotive force (emf) at base speed, {Omega}{sub b} is the base speed in electrical radians per second, and I{sub R} is the rms current rating of the motor windings. The prototype machine that was delivered to ORNL has about 1.5 times as much inductance as a typical PMSM with distributed integral slot windings. The inventors of the FSCW method, who designed the prototype machine, remarked that they were 'too successful' in incorporating inductance into their machine and that steps would be taken to modify the design methodology to reduce the inductance to the optimum value. This study shows a significant advantage of having the higher inductance rather than the optimal value because it enables the motor to develop the required power at lower current thereby reducing motor and inverter losses and improving efficiency. The main problem found with high inductance machines driven by a conventional phase advance (CPA) method is that the motor current at high speed depends solely on machine parameters and is virtually independent of the load level and the direct current (dc) supply voltage. Thus, the motor current is virtually the same at no load as at full load resulting in poor efficiency at less than full load conditions. While an inductance higher than the value cited above is warranted, it still does not ensure that the motor current is proportional to load; consequently, the problem of low efficiency at high speed and partial load is not resolved but is only mitigated. A common definition of 'base speed' is the speed at which the voltage applied to the motor armature is equal to the magnitude of the back-emf. The results in this study indicate that the dc supply voltage should be adequate to drive rated current into the motor winding at the specified base speed. At a minimum this requires sufficient voltage to overcome not only the back-emf but also the voltage drop across the internal impedance of the machine. For a high inductance PMSM, the internal impedance at base speed can be considerable and substantial additional voltage is required to overcome the internal voltage drop. It is further shown that even more voltage than the minimum required for injecting rated current at base speed can be beneficial by allowing the required power to be developed at lower current, which reduces losses in the motor and inverter components. Further, it is shown that the current is minimized at a unique speed; consequently, there may be room for optimization if the drive spends a substantial amount of its operating life at a certain speed (for example 60 mph). In this study, fundamental frequency phasor models are developed for a synchronous PMSM and the control systems that drive them is CPA. The models were compared with detailed simulations to show their validity. The result was used to design a traction drive control system with optimized efficiency to drive the fractional-slot motor with concentrated windings. The goal is to meet or exceed the FreedomCAR inverter cost and performance targets.

McKeever, John W [ORNL; Patil, Niranjan [University of Tennessee, Knoxville (UTK); Lawler, Jack [ORNL

2007-07-01T23:59:59.000Z

338

Best Practices for Energy Efficient Cleanrooms Efficient HVAC Systems: Variable-Speed-Drive Chillers  

E-Print Network (OSTI)

the portion of chiller energy usage was significant. It is,Figure 1. Benchmarked HVAC energy usages in a semiconductor2. Benchmarked cleanroom energy usages in a semiconductor

Xu, Tengfang

2005-01-01T23:59:59.000Z

339

Individual Pitch Control for Mitigation of Power Fluctuation of Variable Speed Wind Turbines  

E-Print Network (OSTI)

, China mcheng@seu.edu.cn Abstract-- Grid connected wind turbines are the sources of power fluctuations and the individual pitch controller is designed. The simulations are performed on the NREL (National Renewable Energy shortage, great efforts have been taken around the world to implement renewable energy projects

Chen, Zhe

340

AN INVESTIGATION OF PERFORMANCE BENEFITS AND TRIM REQUIREMENTS OF A VARIABLE SPEED HELICOPTER ROTOR.  

E-Print Network (OSTI)

??This study primarily examines the main rotor power reductions possible through variation in rotor RPM. Simulations were based on the UH-60 Blackhawk helicopter, and emphasis… (more)

Steiner, Jason

2008-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "variable speed permanent" 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

Optimizing the operation of an urban district heating system by means of variable speed drives  

Science Conference Proceedings (OSTI)

In this work is presenting an urban district heating system which is subjected to a modernization process. The urban district heating system is composed by the pumping station of the primary heat carrier and the district heating stations. The modernization ... Keywords: district heating system, energetic efficiency, pumping station, static frequency converter, testing

Sorin Ioan Deaconu; Gabriel Nicolae Popa; Iosif Popa

2008-07-01T23:59:59.000Z

342

A Generalized Inverter Control Method for a Variable Speed Wind Power System Under Unbalanced Operting Conditions.  

E-Print Network (OSTI)

??This thesis presents a generalized control method for complete harmonic elimination and adjustable power factor of a grid side inverter under unbalanced operating conditions used… (more)

Wu, Shuang

2010-01-01T23:59:59.000Z

343

Development and Validation of WECC Variable Speed Wind Turbine Dynamic Models for Grid Integration Studies  

DOE Green Energy (OSTI)

This paper describes reduced-order, simplified wind turbine models for analyzing the stability impact of large arrays of wind turbines with a single point of network interconnection.

Behnke, M.; Ellis, A.; Kazachkov, Y.; McCoy, T.; Muljadi, E.; Price, W.; Sanchez-Gasca, J.

2007-09-01T23:59:59.000Z

344

Fixed and variable speed induction generators for real power loss minimization  

Science Conference Proceedings (OSTI)

The application of induction generators in the wind power industry is standard practice. An induction generator draws reactive power from the network depending on its real power output, such that the greater the real power exported to the network, the ... Keywords: doubly- fed induction generator, induction generator, line loss, reactive power

S. Durairaj; D. Flynn; B. Fox

2008-02-01T23:59:59.000Z

345

Best Practices for Energy Efficient Cleanrooms Efficient HVAC Systems: Variable-Speed-Drive Chillers  

E-Print Network (OSTI)

sizing ? Cooling tower and condenser optimization ? Controland cooling tower or condenser fans. Figure 1 and Figure 2those with evaporative condensers are more efficient than

Xu, Tengfang

2005-01-01T23:59:59.000Z

346

Best Practices for Energy Efficient Cleanrooms Efficient HVAC Systems: Variable-Speed-Drive Chillers  

E-Print Network (OSTI)

Right sizing ? Cooling tower and condenser optimization ?chillers, water pumps, and cooling tower or condenser fans.MUAH + RCU Fans Pumps Cooling Towers Figure 1. Benchmarked

Xu, Tengfang

2005-01-01T23:59:59.000Z

347

Analysis of a variable speed vapor compression system using artificial neural networks  

Science Conference Proceedings (OSTI)

An artificial neural network (ANN) is a mathematical model that is inspired by the operation of biological neural networks. However, this is typically considered a computational model. An ANN can easily adapt to multiple situations and extract information ... Keywords: Artificial neural network, Energetic performance, Hidden neurons, Mapping configuration, Simulated annealing, Vapor compression system

J. M. Belman-Flores; S. E. Ledesma; M. G. Garcia; J. Ruiz; J. L. RodríGuez-MuñOz

2013-09-01T23:59:59.000Z

348

Plenary lecture 9: generation of electrical energy with variable speed in microhydro and eolian power plant  

Science Conference Proceedings (OSTI)

The mini hydroelectric power plant are built to use the flow of the small rivers. The main disadvantage of these systems is the reduced capacity to store a high quantity of water which should ensure the long term running of the hydroelectric plants during ...

Sorin Deaconu

2009-07-01T23:59:59.000Z

349

Analysis and Design of a High Power Density Axial Flux Permanent Magnet Linear Synchronous Machine Used for Stirling System  

Science Conference Proceedings (OSTI)

a high power density axial flux permanent magnet linear synchronous machine and the stirling system will be introduced. This machine is a tubular axial flux permanent magnet machine. It comprises two parts: stator and mover. With the 2D finite-element ... Keywords: permanent magnet, stirling engine, linear motor

Ping Zheng; Xuhui Gan; Lin Li

2010-09-01T23:59:59.000Z

350

This paper describes the integrated modeling of a permanent magnet (PM) motor used in an electromechanical actuator  

E-Print Network (OSTI)

ABSTRACT This paper describes the integrated modeling of a permanent magnet (PM) motor used and Field Oriented Control of Permanent Magnet (PM) Motor for High Performance EMA 2010-01-1742 Published 11 of a permanent magnet motor and describes both the control and thermal performance of the motor in following

Wu, Shin-Tson

351

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

E-Print Network (OSTI)

Permanent Magnet Synchronous Motor with Brushless Field Excitation Seong Taek Lee1,2 , Timothy A. Burress1 permanent magnet synchronous motor (IPMSM). The conventional two-axis IPMSM model is modified to include motor of a hybrid electric vehicle. I. INTRODUCTION The interior permanent magnet synchronous motor

Tolbert, Leon M.

352

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

353

Control of Surface Mounted Permanent Magnet Motors with Special Application to Fractional-Slot Concentrated Windings  

SciTech Connect

It is well known that the ability of the permanent magnet synchronous machine (PMSM) to operate over a wide constant power speed range (CPSR) is dependent upon the machine inductance [1,2,3,4,5]. Early approaches for extending CPSR operation included adding supplementary inductance in series with the motor [1] and the use of anti-parallel thyristor pairs in series with the motor-phase windings [5]. The increased inductance method is compatible with a voltage-source inverter (VSI) controlled by pulse-width modulation (PWM) which is called the conventional phase advance (CPA) method. The thyristor method has been called the dual mode inverter control (DMIC). Neither of these techniques has met with wide acceptance since they both add cost to the drive system and have not been shown to have an attractive cost/benefit ratio. Recently a method has been developed to use fractional-slot concentrated windings to significantly increase the machine inductance [6]. This latest approach has the potential to make the PMSM compatible with CPA without supplemental external inductance. If the performance of such drive is acceptable, then the method may make the PMSM an attractive option for traction applications requiring a wide CPSR. A 30 pole, 6 kW, 6000 maximum revolutions per minute (rpm) prototype of the fractional-slot PMSM design has been developed [7]. This machine has significantly more inductance than is typical of regular PMSMs. The prototype is to be delivered in late 2005 to the Oak Ridge National Laboratory (ORNL) for testing and development of a suitable controller. In advance of the test/control development effort, ORNL has used the PMSM models developed over a number of previous studies to study the steady-state performance of high-inductance PMSM machines with a view towards control issues. The detailed steady-state model developed includes all motor and inverter-loss mechanisms and will be useful in assessing the performance of the dynamic controller to be developed in future work. This report documents the results of this preliminary investigation.

Lawler, J.S.

2005-12-21T23:59:59.000Z

354

Contol of Surface Mounted Permanent Magnet Motors with Special Application to Motors with Fractional-Slot Concentrated Windings  

SciTech Connect

A 30-pole, 6-kW prototype of a fractional-slot permanent magnet synchronous motor (PMSM) design has been developed to operate at a maximum speed of 6000 rpm [1,2]. This machine has significantly more inductance than regular PMSMs with distributed windings. The prototype was delivered in April 2006 to the Oak Ridge National Laboratory (ORNL) for testing and development of a suitable controller. To prepare for this test/control development effort, ORNL used PMSM models developed over a number of previous studies to preview the control issues that arise when a dynamic controller drives a high inductance PMSM machine during steady state performance evaluations. The detailed steady state model developed includes all motor and inverter loss mechanisms and was useful for assessing the performance of the dynamic controller before it was put into operation. This report documents the results of tests demonstrating the effectiveness of ORNL's simple low-cost control scheme during characterization of the fractional-slot concentrated windings (FSCW) PMSM motor. The control scheme is simple because only the supply voltage magnitude and the phase angle between the back-electromotive force (emf) and the supply voltage is controlled. It is low-cost because it requires no current or phase voltage sensors.

Patil, N.; Lawler, J.S.; McKeever, J.

2007-07-31T23:59:59.000Z

355

Contol of Surface Mounted Permanent Magnet Motors with Special Application to Motors with Fractional-Slot Concentrated Windings  

SciTech Connect

A 30-pole, 6-kW prototype of a fractional-slot permanent magnet synchronous motor (PMSM) design has been developed to operate at a maximum speed of 6000 rpm [1,2]. This machine has significantly more inductance than regular PMSMs with distributed windings. The prototype was delivered in April 2006 to the Oak Ridge National Laboratory (ORNL) for testing and development of a suitable controller. To prepare for this test/control development effort, ORNL used PMSM models developed over a number of previous studies to preview the control issues that arise when a dynamic controller drives a high inductance PMSM machine during steady state performance evaluations. The detailed steady state model developed includes all motor and inverter loss mechanisms and was useful for assessing the performance of the dynamic controller before it was put into operation. This report documents the results of tests demonstrating the effectiveness of ORNL's simple low-cost control scheme during characterization of the fractional-slot concentrated windings (FSCW) PMSM motor. The control scheme is simple because only the supply voltage magnitude and the phase angle between the back-electromotive force (emf) and the supply voltage is controlled. It is low-cost because it requires no current or phase voltage sensors.

Patil, N.; Lawler, J.S.; McKeever, J.

2007-07-31T23:59:59.000Z

356

Effects of mineral aerosols on the summertime climate of southwest Asia: Incorporating subgrid variability in a dust emission scheme  

E-Print Network (OSTI)

[1] Improvements in modeling mineral aerosols over southwest Asia are made to the dust scheme in a regional climate model by representing subgrid variability of both wind speed and surface roughness length. The new module ...

Marcella, Marc Pace

357

Would you keep speeding through a speed trap if you got a ticket there before?  

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

you keep speeding through a speed trap if you got a ticket there before? you keep speeding through a speed trap if you got a ticket there before? Probably (hopefully) not. Likewise, taking advantage of lessons learned on our capital asset and clean-up projects is not only fiscally prudent, but also just makes good common sense. DOE Order 413.3B "Program and Project Management for the Acquisition of Capital Assets" re- quires formal lessons learned to be documented for a project, as follows:  Within 90 days of CD-3 approval, to cover up-front planning and design lessons learned  Within 90 days of CD-4 approval, to cover project execution and facility start-up les- sons learned These should be formal documents and should be submitted to OECM for sharing throughout the

358

Speed of the Earth : illusion and experience of speed and scale  

E-Print Network (OSTI)

The Speed of the Earth is a proposed sculpture dealing with light as pure experience within the context of short-lived rapid movement and large scale horizontal orientation within the environment. This will be accomplished ...

Benoff, Mitchell

1993-01-01T23:59:59.000Z

359

Design and analysis of a permanent magnet generator for naval applications  

E-Print Network (OSTI)

This paper discusses the electrical and magnetic design and analysis of a permanent magnet generation module for naval applications. Numerous design issues are addressed and several issues are raised about the potential ...

Rucker, Jonathan E. (Jonathan Estill)

2005-01-01T23:59:59.000Z

360

EA-1895: Lolo Creek Permanent Weir Construction near town of Weippe,  

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

5: Lolo Creek Permanent Weir Construction near town of 5: Lolo Creek Permanent Weir Construction near town of Weippe, Clearwater County, Idaho EA-1895: Lolo Creek Permanent Weir Construction near town of Weippe, Clearwater County, Idaho Summary DOE's Bonneville Power Administration is preparing this EA to evaluate the potential environmental impacts of replacing an existing seasonal fish weir with a permanent weir, which would be used to monitor federally-listed Snake River steelhead and collect spring Chinook salmon adults to support ongoing supplementation programs in the watershed. The Bureau of Land Management, a cooperating agency, preliminarily determined Lolo Creek to be suitable for Congressional designation into the Wild and Scenic River System. The EA includes a Wild and Scenic River Section 7 analysis.

Note: This page contains sample records for the topic "variable speed permanent" 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

Statement of Secretaries Salazar and Chu on the Permanent Plugging of  

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

Secretaries Salazar and Chu on the Permanent Plugging Secretaries Salazar and Chu on the Permanent Plugging of Macondo well Statement of Secretaries Salazar and Chu on the Permanent Plugging of Macondo well September 19, 2010 - 12:00am Addthis WASHINGTON, DC - Secretary of the Interior Ken Salazar and Energy Secretary Steven Chu today issued the following statement regarding the permanent plugging of BP's Macondo well. "With the successful first intercept by the relief well and our confirmation through pressure tests that the cement plugs are secure, we can now declare BP's Macondo well effectively dead. At the direction of President Obama and under the leadership of National Incident Commander Thad Allen, we have worked tirelessly and relentlessly as a US Team to reach this point and to provide oversight and direction to the source

362

DOE-Sponsored Field Test Finds Potential for Permanent Storage of CO2 in  

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

Field Test Finds Potential for Permanent Storage of Field Test Finds Potential for Permanent Storage of CO2 in Lignite Seams DOE-Sponsored Field Test Finds Potential for Permanent Storage of CO2 in Lignite Seams November 4, 2010 - 1:00pm Addthis Washington, DC - A field test sponsored by the U.S. Department of Energy (DOE) has demonstrated that opportunities to permanently store carbon in unmineable seams of lignite may be more widespread than previously documented. This finding supports national efforts to address climate change through long-term storage of CO2 in underground geologic reservoirs. Lowering the core barrel at the PCOR Partnership lignite site.The PCOR Partnership, one of seven partnerships in DOE's Regional Carbon Sequestration Partnership Program, collaborated with Eagle Operating Inc. (Kenmare, N.D.) to complete the field test in Burke County, N.D. In March

363

Fabrication and Performance of Silicon-Embedded Permanent-Magnet Microgenerators  

E-Print Network (OSTI)

This paper focuses on the design, fabrication, and characterization of silicon-packaged permanent-magnet (PM) microgenerators. The use of silicon packaging favors fine control on shape and dimensions in batch fabrication ...

Herrault, Florian

364

Prospects for Non-Rare Earth Permanent Magnets for Traction Motors and Generators  

Science Conference Proceedings (OSTI)

With the advent of high-flux density permanent magnets based on rare earth elements such as neodymium (Nd) in the 1980s, permanent magnet-based electric machines had a clear performance and cost advantage over induction machines when weight and size were factors such as in hybrid electric vehicles and wind turbines. However, the advantages of the permanent magnet-based electric machines may be overshadowed by supply constraints and high prices of their key constituents, rare earth elements, which have seen nearly a 10-fold increase in price in the last 5 years and the imposition of export limits by the major producing country, China, since 2010. We outline the challenges, prospects, and pitfalls for several potential alloys that could replace Nd-based permanent magnets with more abundant and less strategically important elements.

Kramer, Matthew; McCallum, Kendall; Anderson, Iver; Constantinides, Steven

2012-06-29T23:59:59.000Z

365

Experimental verification for the design of a doubly-fed permanent magnetic generator  

E-Print Network (OSTI)

This is a continuous work on the project of a doubly-fed permanent magnet (DFPM) generator for wind turbines. The construction of a prototype machine was finally finished and experiments were conducted to verify the design ...

Lu, Bin, Ph. D. Massachusetts Institute of Technology

2007-01-01T23:59:59.000Z

366

Performance Assessment of a Variable Refrigerant Flow Heat Pump Air Conditioning System  

Science Conference Proceedings (OSTI)

Variable refrigerant flow (VRF) technology uses smart integrated controls, variable speed drives, and refrigerant piping to provide energy efficiency, flexible operation, ease of installation, low noise, zone control, and comfort through all-electric technology. This report describes and documents the construction, performance, and application of a heat pump air conditioning system that uses VRF technology8212the Daikin VRV system. This variable refrigerant volume (VRV) system is manufactured by Daikin I...

2008-12-17T23:59:59.000Z

367

A design for improved performance of interior permanent magnet synchronous motor for hybrid electric vehicle  

Science Conference Proceedings (OSTI)

This paper investigates the layout of a magnet shape on the performance of an interior permanent magnet (IPM) synchronous motor. The motor is used in a hybrid electric vehicle. The IPM motor is a pancake shaped motor that has permanent magnets inside the rotor. The motor acts as a rotational electrodynamic machine between the engine and transmission. The main purpose of redesigning the shape of the magnet is to improve the motor performance

Seong Yeop Lim

2006-01-01T23:59:59.000Z

368

LIRR High-Speed Flywheel Demonstration  

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

LIRR High-Speed Flywheel LIRR High-Speed Flywheel Demonstration Guy Sliker Program Manager Research & Technology Development New York Power Authority This project is part of the Joint Energy Storage Initiative between the New York State Energy Research and Development Authority (NYSERDA) and the Energy Storage Systems Program of the U.S. Department of Energy (DOE/ESS), and managed by Sandia National Laboratories (SNL). Presentation Layout Introduction Flywheel Description Project Reasoning Project Objective Project Participants Expected Benefits New York Power Authority Highlights A public benefit energy corporation founded 1931 Largest non-federal public electric utility in United States Wholesale power supplier throughout New York State and neighboring states as required by law

369

High-speed CARIBU and Other Behemoths  

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

Question: Why did the caribou cross the road, at 76 million miles per hour? Answer: To catch up with the chicken. Visitors to the Department of Energy’s Argonne National Laboratory won’t actually encounter any hyper-speed fowl, but they will see a high-speed CARIBU, which recently started to chase other exotic beasts in the particle zoo. Argonne’s CARIBU – which stands for Californium Rare Isotope Breeder Upgrade – is designed to study the inner part of an atom known as its nucleus. A nucleus consists of a collection of two types of particles, the proton, with a positive charge, and the neutron, with no charge, just mass. Those particles themselves are made of even smaller particles called quarks. CARIBU creates extra-heavy (neutron-rich) nuclei, and then spits them out of a nozzle for acceleration.

370

High-speed massively parallel scanning  

DOE Patents (OSTI)

A new technique for recording a series of images of a high-speed event (such as, but not limited to: ballistics, explosives, laser induced changes in materials, etc.) is presented. Such technique(s) makes use of a lenslet array to take image picture elements (pixels) and concentrate light from each pixel into a spot that is much smaller than the pixel. This array of spots illuminates a detector region (e.g., film, as one embodiment) which is scanned transverse to the light, creating tracks of exposed regions. Each track is a time history of the light intensity for a single pixel. By appropriately configuring the array of concentrated spots with respect to the scanning direction of the detection material, different tracks fit between pixels and sufficient lengths are possible which can be of interest in several high-speed imaging applications.

Decker, Derek E. (Byron, CA)

2010-07-06T23:59:59.000Z

371

Energy curable compositions having improved cure speeds  

DOE Patents (OSTI)

A composition and method provide improved physical properties and cure speed of polyurethane precursors, with or without free radical polymerizable monomers or oligomers present, by use of a two component catalyst system. The resin blend can be activated with a latent organometallic catalyst combined with an organic peroxide which can be a hydroperoxide or an acyl peroxide to decrease the cure time while increasing the break energy and tangent modulus of the system.

Halm, Leo W. (Blaine, MN)

1993-01-01T23:59:59.000Z

372

All aboard for high-speed rail  

SciTech Connect

A sleek, bullet-nosed train whizzing across the countryside is a fairly common sight in many nations. Since the Train a Grande Vitesse (TGV)--the record-setting ``train with great speed``--was introduced in France in 1981, Germany, Japan, and other countries have joined the high-speed club. In addition, the Eurostar passenger train, which travels between Great Britain and France through the Channel Tunnel, can move at 186 miles per hour once it reaches French tracks. Despite the technology`s growth elsewhere, rapid rail travel has not been seen on US shores beyond a few test runs by various manufacturers. Before the end of the century, however, American train spotters will finally be able to see some very fast trains here too. In March, Washington, DC-based Amtrak announced the purchase of 18 American Flyer high-speed train sets for the Northeast Corridor, which stretches from Boston through new York to the nation`s capital. Furthermore, Florida will get its own system by 2004, and other states are now taking a look at the technology. The American Flyer--designed by Montreal-based Bombardier and TGV manufacturer GEC Alsthom Transport in Paris--should venture onto US rails by 1999. Traveling at up to 150 miles per hour, the American Flyer will cut the New York-Boston run from 4 1/2 hours to 3 hours and reduce New York-Washington trip time from 3 hours to less than 2 3/4. Amtrak hopes the new trains and better times will earn it a greater share of travelers from air shuttles and perhaps from Interstate 95. This article describes how technologies that tilt railcars and propel the world`s fastest trains will be merged into one train set for the American Flyer, Amtrak`s first trip along high-speed rails.

Herman, D.

1996-09-01T23:59:59.000Z

373

Modernizing Newton, to work at any speed  

E-Print Network (OSTI)

Modification of three ideas underlying Newton's original world view, with only minor changes in context, might offer two advantages to introductory physics students. First, the students will experience less cognitive dissonance when they encounter relativistic effects. Secondly, the map-based Newtonian tools that they spend so much time learning about can be extended to high speeds, non-inertial frames, and even (locally, of course) to curved-spacetime.

P. Fraundorf

2001-10-07T23:59:59.000Z

374

Energy curable compositions having improved cure speeds  

DOE Patents (OSTI)

The composition and method provide improved physical properties and cure speed of polyurethane precursors, with or without free radical polymerizable monomers or oligomers present, by use of a two component catalyst system. The resin blend can be activated with a latent organometallic catalyst combined with an organic peroxide which can be a hydroperoxide or an acyl peroxide to decrease the cure time while increasing the break energy and tangent modulus of the system.

Halm, L.W.

1993-05-18T23:59:59.000Z

375

Estimated Global Hydrographic Variability  

Science Conference Proceedings (OSTI)

An estimate is made of the three-dimensional global oceanic temperature and salinity variability, omitting the seasonal cycle, both as a major descriptive element of the ocean circulation and for use in the error estimates of state estimation. ...

Gaël Forget; Carl Wunsch

2007-08-01T23:59:59.000Z

376

Understanding Biomass Feedstock Variability  

SciTech Connect

If the singular goal of biomass logistics and the design of biomass feedstock supply systems is to reduce the per ton supply cost of biomass, these systems may very well develop with ultimate unintended consequences of highly variable and reduced quality biomass feedstocks. This paper demonstrates that due to inherent species variabilities, production conditions, and differing harvest, collection, and storage practices, this is a very real scenario that biomass producers and suppliers as well as conversion developers should be aware of. Biomass feedstock attributes of ash, carbohydrates, moisture, and particle morphology will be discussed. We will also discuss specifications for these attributes, inherent variability of these attributes in biomass feedstocks, and approaches and solutions for reducing variability for improving feedstock quality.

Kevin L. Kenney; William A. Smith; Garold L. Gresham; Tyler L. Westover

2013-01-01T23:59:59.000Z

377

Dual power, constant speed electric motor system  

DOE Patents (OSTI)

A dual capacity permanent split capacitor electric motor system is provided with a stator having main and auxiliary windings. The main stator winding includes two winding sections which are connected in parallel with each other and across a pair of line terminals while the auxiliary winding is connected in series with a capacitor to form a circuit branch which is connected between the line terminals for operation at a first output power level. Switching means are provided to reconnect the main stator winding sections in series with each other and in series with a second capacitor to form a circuit branch which is connected between the line terminals while the stator auxiliary winding is connected directly between the line terminals for operation at a second output power level. Automatic rotation reversal occurs when the motor switches from the first to the second output power level.

Kirschbaum, Herbert S. (Asheville, NC)

1984-01-01T23:59:59.000Z

378

Dual power, constant speed electric motor system  

DOE Patents (OSTI)

A dual capacity permanent split capacitor electric motor system is provided with a stator having main and auxiliary windings. The main stator winding includes two winding sections which are connected in parallel with each other and across a pair of line terminals while the auxiliary winding is connected in series with a capacitor to form a circuit branch which is connected between the line terminals for operation at a first output power level. Switching means are provided to reconnect the main stator winding sections in series with each other and in series with a second capacitor to form a circuit branch which is connected between the line terminals while the stator auxiliary winding is connected directly between the line terminals for operation at a second output power level. Automatic rotation reversal occurs when the motor switches from the first to the second output power level. 6 figs.

Kirschbaum, H.S.

1984-07-31T23:59:59.000Z

379

CRADA Final Report: Application of Dual-Mode Invertor Control to Commercially Available Radial-Gap Permanent Magnet Motors - Vol. 1  

SciTech Connect

John Deere and Company (Deere), their partner, UQM Technologies, Inc. (UQM), and the Oak Ridge National Laboratory's (ORNL's) Power Electronics and Electric Machinery Research Center (PEEMRC) recently completed work on the cooperative research and development agreement (CRADA) Number ORNL 04-0691 outlined in this report. CRADA 04-0691 addresses two topical issues of interest to Deere: (1) Improved characterization of hydrogen storage and heat-transfer management; and (2) Potential benefits from advanced electric motor traction-drive technologies. This report presents the findings of the collaborative examination of potential operational and cost benefits from using ORNL/PEEMRC dual-mode inverter control (DMIC) to drive permanent magnet (PM) motors in applications of interest to Deere. DMIC was initially developed and patented by ORNL to enable PM motors to be driven to speeds far above base speed where the back-electromotive force (emf) equals the source voltage where it is increasingly difficult to inject current into the motor. DMIC is a modification of conventional phase advance (CPA). DMIC's dual-speed modes are below base speed, where traditional pulse-width modulation (PWM) achieves maximum torque per ampere (amp), and above base speed, where six-step operation achieves maximum power per amp. The modification that enables DMIC adds two anti-parallel thyristors in each of the three motor phases, which consequently adds the cost of six thyristors. Two features evaluated in this collaboration with potential to justify the additional thyristor cost were a possible reduction in motor cost and savings during operation because of higher efficiency, both permitted because of lower current. The collaborative analysis showed that the reduction of motor cost and base cost of the inverter was small, while the cost of adding six thyristors was greater than anticipated. Modeling the DMIC control displayed inverter efficiency gains due to reduced current, especially under light load and higher speed. This current reduction, which is the salient feature of DMIC, may be significant when operating duty cycles have low loads at high frequencies. Reduced copper losses make operation more efficient thereby reducing operating costs. In the Deere applications selected for this study, the operating benefit was overshadowed by the motor's rotational losses. Rotational losses of Deere 1 and Deere 2 dominate the overall drive efficiency so that their reduction has the greatest potential to improve performance. A good follow-up project would be to explore cost erective ways to reduce the rotational losses buy 66%.

Lawler, J.S. (U. Tennessee-Knoxville); McKeever, J.W.; Downing, M.E.; Stahlhut, R.D (John Deere); Bremmer, R. (John Deere); Shoemaker, J.M. (John Deere); Seksarian, A.K. (john Deere); Poore, B. (John Deere); Lutz, J. (UQM)

2006-05-01T23:59:59.000Z

380

CRADA Final Report: Application of Dual-Mode Invertor Control to Commercially Available Radial-Gap Permanent Magnet Motors - Vol. 1  

DOE Green Energy (OSTI)

John Deere and Company (Deere), their partner, UQM Technologies, Inc. (UQM), and the Oak Ridge National Laboratory's (ORNL's) Power Electronics and Electric Machinery Research Center (PEEMRC) recently completed work on the cooperative research and development agreement (CRADA) Number ORNL 04-0691 outlined in this report. CRADA 04-0691 addresses two topical issues of interest to Deere: (1) Improved characterization of hydrogen storage and heat-transfer management; and (2) Potential benefits from advanced electric motor traction-drive technologies. This report presents the findings of the collaborative examination of potential operational and cost benefits from using ORNL/PEEMRC dual-mode inverter control (DMIC) to drive permanent magnet (PM) motors in applications of interest to Deere. DMIC was initially developed and patented by ORNL to enable PM motors to be driven to speeds far above base speed where the back-electromotive force (emf) equals the source voltage where it is increasingly difficult to inject current into the motor. DMIC is a modification of conventional phase advance (CPA). DMIC's dual-speed modes are below base speed, where traditional pulse-width modulation (PWM) achieves maximum torque per ampere (amp), and above base speed, where six-step operation achieves maximum power per amp. The modification that enables DMIC adds two anti-parallel thyristors in each of the three motor phases, which consequently adds the cost of six thyristors. Two features evaluated in this collaboration with potential to justify the additional thyristor cost were a possible reduction in motor cost and savings during operation because of higher efficiency, both permitted because of lower current. The collaborative analysis showed that the reduction of motor cost and base cost of the inverter was small, while the cost of adding six thyristors was greater than anticipated. Modeling the DMIC control displayed inverter efficiency gains due to reduced current, especially under light load and higher speed. This current reduction, which is the salient feature of DMIC, may be significant when operating duty cycles have low loads at high frequencies. Reduced copper losses make operation more efficient thereby reducing operating costs. In the Deere applications selected for this study, the operating benefit was overshadowed by the motor's rotational losses. Rotational losses of Deere 1 and Deere 2 dominate the overall drive efficiency so that their reduction has the greatest potential to improve performance. A good follow-up project would be to explore cost erective ways to reduce the rotational losses buy 66%.

Lawler, J.S. (U. Tennessee-Knoxville); McKeever, J.W.; Downing, M.E.; Stahlhut, R.D (John Deere); Bremmer, R. (John Deere); Shoemaker, J.M. (John Deere); Seksarian, A.K. (john Deere); Poore, B. (John Deere); Lutz, J. (UQM)

2006-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "variable speed permanent" 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

Factors affecting the permanence of livestock projects undertaken by Heifer International-Mexico  

E-Print Network (OSTI)

Heifer International-Mexico (HI-M), a hunger-relieving non-profit organization, collaborates with the Direccin? General de Educacin? Tecnolg?ica Agropecuaria-Durango (DGETA) to establish livestock projects involving resource-poor families in the state of Durango, Mexico. This study identified and analyzed the factors affecting the permanence of hog and dairy cow projects in four communities in the state of Durango, Mexico. The researcher interviewed seven project managers and 35 beneficiaries to identify the factors affecting the permanence of livestock projects. From their responses, the researcher developed a list of 22 factors that promoted the permanence of the livestock projects. Key points included personal interaction between beneficiaries in the group(s) and project manager(s), knowledge and skills obtained from workshops, and household economics. The researcher developed a separate list of 20 factors that inhibited the permanence of the livestock projects. Key points included difficulties in livestock production and poor personal interaction and communication between beneficiaries and project managers. Two diagrams illustrate the commonalities and differences advocated by the two groups for both lists. Beneficiaries and project managers shared eight of the 14 factors advocated to promote the permanence of livestock projects. Beneficiaries had four factors unique to their group and the project managers had two factors unique to their group. Beneficiaries and project managers shared seven of the 13 factors advocated to inhibit the permanence of livestock projects. Four factors were unique to beneficiaries while two factors were unique to project managers. The researcher used a force field analysis based concept labeled the "line of permanence," to illustrate the factors affecting the permanence of HI-M's livestock projects in the communities. Community A was the only location where the interviewees identified more factors inhibiting the permanence of a livestock project. Community A was also the only community that no longer had animals HI-M donated to the community. In contrast to Community A, project managers and beneficiaries in Communities A, B, and C each identified more factors that promoted the permanence of the livestock projects. The author made recommendations based on the findings of the study for HI-M and DGETA to improve the manner by which they undertake livestock projects.

Arispe, Sergio Adrian

2003-01-01T23:59:59.000Z

382

Vehicle Technologies Office: Fact #222: June 24, 2002 Speed versus...  

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

4, 2002 Speed versus Fuel Economy: Slow down to get more miles to the gallon to someone by E-mail Share Vehicle Technologies Office: Fact 222: June 24, 2002 Speed versus Fuel...

383

Excitation and control of a high-speed induction generator  

E-Print Network (OSTI)

This project investigates the use of a high speed, squirrel cage induction generator and power converter for producing DC electrical power onboard ships and submarines. Potential advantages of high speed induction generators ...

Englebretson, Steven Carl

2005-01-01T23:59:59.000Z

384

The Probability Distribution of Land Surface Wind Speeds  

Science Conference Proceedings (OSTI)

The probability density function (pdf) of land surface wind speeds is characterized using a global network of observations. Daytime surface wind speeds are shown to be broadly consistent with the Weibull distribution, while nighttime surface wind ...

Adam H. Monahan; Yanping He; Norman McFarlane; Aiguo Dai

2011-08-01T23:59:59.000Z

385

NETL: News Release - IntelliPipe Technology: Wired for Speed...  

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

Speed Achieved in Major Field Test in Wyoming CASPER, WY - Methods for gathering downhole oil and gas well data have grown more sophisticated in recent years, but the speed with...

386

Development of Improved Traveler Survey Methods for High-Speed Intercity Passenger Rail Planning  

E-Print Network (OSTI)

High-speed passenger rail is seen by many in the U.S. transportation policy and planning communities as an ideal solution for fast, safe, and resource-efficient mobility in high-demand intercity corridors. To expand the body of knowledge for high-speed intercity passenger rail in the U.S., the overall goal of this dissertation was to better understand the demand for high-speed intercity passenger rail services in small- or medium-sized intermediate communities and improve planners' ability to estimate such demand through traveler surveys; specifically, the use of different experimental designs for stated preference questions and the use of images to describe hypothetical travel alternatives in traveler surveys. In pursuit of this goal, an Internet-based survey was distributed to residents of Waco and Temple, two communities located along the federally-designated South Central High-Speed Rail Corridor in Central Texas. A total of 1,160 surveys were obtained from residents of the two communities. Mixed logit travel mode choice models developed from the survey data revealed valuable findings that can inform demand estimates and the design of traveler surveys for high-speed intercity passenger rail planning activities. Based on the analysis presented in this dissertation, ridership estimates for new high-speed intercity passenger rail lines that are planned to serve intermediate communities should not assume that residents of these communities have similar characteristics and values. The d-efficient stated preference experimental design was found to provide a mode choice model with a better fit and greater significance on key policy variables than the adaptive design and therefore is recommended for use in future surveys. Finally, it is recommended that surveys should consider the use of images of proposed train services to aid respondent decision-making for stated preference questions, but only if the images used in the survey depict equipment that could be realistically deployed in the corridor.

Sperry, Benjamin

2012-05-01T23:59:59.000Z

387

NIST Calls for Suggestions to Speed Computer Incident ...  

Science Conference Proceedings (OSTI)

NIST Calls for Suggestions to Speed Computer Incident Teams Responses. From NIST Tech Beat: June 28, 2013. ...

2013-07-10T23:59:59.000Z

388

Design of a variable-conductance vacuum insulation  

DOE Green Energy (OSTI)

This paper describes one approach to the design of a variable-conductance vacuum insulation. In this design, the vacuum insulation consists of a permanently sealed, thin sheet steel, evacuated envelope of whatever geometry is required for the application. The steel envelope is supported internally against the atmospheric pressure loads by an array of discrete, low-conductance, ceramic supports, and radiative heat transfer is blocked by layers of thin metal radiation shields. Thermal conductance through this insulation is controlled electronically by changing the temperature of a small metal hydride connected to the vacuum envelope. The hydride reversibly absorbs/desorbs hydrogen to produce a hydrogen pressure typically within the range from less than 10{sup {minus}6} to as much as 1 torr. Design calculations are compared with results from laboratory tests of bench scale samples, and some possible automotive applications for this variable-conductance vacuum insulation are suggested.

Benson, D K; Potter, T F; Tracy, C E

1994-01-01T23:59:59.000Z

389

Virtual Wind Speed Sensor for Wind Turbines Andrew Kusiak1  

E-Print Network (OSTI)

Virtual Wind Speed Sensor for Wind Turbines Andrew Kusiak1 ; Haiyang Zheng2 ; and Zijun Zhang3 Abstract: A data-driven approach for development of a virtual wind-speed sensor for wind turbines is presented. The virtual wind-speed sensor is built from historical wind-farm data by data-mining algorithms

Kusiak, Andrew

390

Wind speed PDF classification using Dirichlet mixtures Rudy CALIF1  

E-Print Network (OSTI)

Wind speed PDF classification using Dirichlet mixtures Rudy CALIF1 , Richard EMILION2 , Ted'Orléans), UMR CNRS 6628 Université d'Orléans, France. Abstract: Wind energy production is very sensitive to instantaneous wind speed fluctuations. Thus rapid variation of wind speed due to changes in the local

Paris-Sud XI, Université de

391

The Access Almanac: Planning for High Speed Rail  

E-Print Network (OSTI)

Planning for High Speed Rail M A R T I N WA C H S C A L I FN O T T O build a high speed rail system and, if so, how toplanning for high speed rail in California been so troubled?

Wachs, Martin

2012-01-01T23:59:59.000Z

392

Lorentz transformation directly from the invariance of the speed of light via the addition law of parallel speeds  

E-Print Network (OSTI)

We show that starting with the addition law of parallel speeds derived as a consequence of the invariance of the speed of light, the Lorentz transformations for the space-time coordinates can be derived.

Bernhard Rothenstein

2007-09-14T23:59:59.000Z

393

Georeactor Variability and Integrity  

E-Print Network (OSTI)

As a deep-Earth energy source, the planetocentric nuclear-fission georeactor concept is on a more secure scientific footing than the previous idea related to the assumed growth of the inner core. Unlike previously considered deep-Earth energy sources, which are essentially constant on a human time-scale, variability in nuclear fission reactors can arise from changes in composition and/or position of fuel, moderators, and neutron absorbers. Tantalizing circumstantial evidence invites inquiry into the possibility of short-term planetocentric nuclear fission reactor variability. This brief communication emphasizes the importance of scientific integrity and highlights the possibility of variable georeactor power output so that these might be borne in mind in future investigations, especially those related to the Earth's heat flux.

J. Marvin Herndon

2005-10-04T23:59:59.000Z

394

Georeactor Variability and Integrity  

E-Print Network (OSTI)

As a deep-Earth energy source, the planetocentric nuclear-fission georeactor concept is on a more secure scientific footing than the previous idea related to the assumed growth of the inner core. Unlike previously considered deep-Earth energy sources, which are essentially constant on a human time-scale, variability in nuclear fission reactors can arise from changes in composition and/or position of fuel, moderators, and neutron absorbers. Tantalizing circumstantial evidence invites inquiry into the possibility of short-term planetocentric nuclear fission reactor variability. This brief communication emphasizes the importance of scientific integrity and highlights the possibility of variable georeactor power output so that these might be borne in mind in future investigations, especially those related to the Earth's heat flux.

Herndon, J M

2005-01-01T23:59:59.000Z

395

Comparison of Geophysical Model Functions for SAR Wind Speed Retrieval in Japanese Coastal Waters  

E-Print Network (OSTI)

Abstract: This work discusses the accuracies of geophysical model functions (GMFs) for retrieval of sea surface wind speed from satellite-borne Synthetic Aperture Radar (SAR) images in Japanese coastal waters characterized by short fetches and variable atmospheric stability conditions. In situ observations from two validation sites, Hiratsuka and Shirahama, are used for comparison of the retrieved sea surface wind speeds using CMOD (C-band model)4, CMOD_IFR2, CMOD5 and CMOD5.N. Of all the geophysical model functions (GMFs), the latest C-band GMF, CMOD5.N, has the smallest bias and root mean square error at both sites. All of the GMFs exhibit a negative bias in the retrieved wind speed. In order to understand the reason for this bias, all SAR-retrieved wind speeds are separated into two categories: onshore wind (blowing from sea to land) and offshore wind (blowing from land to sea). Only offshore winds were found to exhibit the large negative bias, and short fetches from the coastline may be a possible reason for this. Moreover, it is clarified that in both the unstable and stable conditions, CMOD5.N has atmospheric stability effectiveness, and can keep the same accuracy with CMOD5 in the neutral condition. In short, at the moment, CMOD5.N is thought to be the most promising GMF

Yuko Takeyama; Teruo Ohsawa; Katsutoshi Kozai; Charlotte Bay Hasager; Merete Badger

2013-01-01T23:59:59.000Z

396

Sustainably Priced Energy Enterprise Development (SPEED) Goals | Department  

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

Sustainably Priced Energy Enterprise Development (SPEED) Goals Sustainably Priced Energy Enterprise Development (SPEED) Goals Sustainably Priced Energy Enterprise Development (SPEED) Goals < Back Eligibility Investor-Owned Utility Municipal Utility Rural Electric Cooperative Savings Category Bioenergy Alternative Fuel Vehicles Hydrogen & Fuel Cells Buying & Making Electricity Water Solar Heating & Cooling Water Heating Wind Program Info State Vermont Program Type Renewables Portfolio Standard Provider Vermont Public Service Board Vermont's Sustainably Priced Energy Enterprise Development (SPEED) Program was created by legislation in 2005 to promote renewable energy development. The SPEED program itself is not a renewable portfolio goal or standard. However, if the Vermont Public Service Board (PSB) determines that the

397

Lensless Magneto-optic speed sensor  

DOE Patents (OSTI)

Lensless magneto-optic speed sensor. The construction of a viable Faraday sensor has been achieved. Multimode fiber bundles are used to collect the light. If coupled directly into a 100 or 200 .mu.m core fiber, light from a light emitting diode (LED) is sufficient to operate the sensor. In addition, LEDs ensure that no birefringence effects in the input fiber are possible, as the output from such light sources have random polarization. No lens is required since the large diameter optical fibers and thin crystals of materials having high Verdet constants (such as iron garnets) employed permit the collection of a substantial quantity of light. No coupler is required. The maximum amount of light which could reach a detector using a coupler is 25%, while the measured throughput of the fiber-optic bundle without a coupler is about 42%. All of the elements employed in the present sensor are planar, and no particular orientation of these elements is required. The present sensor operates over a wide range of distances from magnetic field sources, and observed signals are large. When a tone wheel is utilized, the signals are independent of wheel speed, and the modulation is observed to be about 75%. No sensitivity to bends in the input or output optical fiber leads was observed. Reliable operation was achieved down to zero frequency, or no wheel rotation.

Veeser, Lynn R. (Los Alamos, NM); Forman, Peter R. (Los Alamos, NM); Rodriguez, Patrick J. (Santa Fe, NM)

1998-01-01T23:59:59.000Z

398

Lensless magneto-optic speed sensor  

DOE Patents (OSTI)

Lensless magneto-optic speed sensor is disclosed. The construction of a viable Faraday sensor has been achieved. Multimode fiber bundles are used to collect the light. If coupled directly into a 100 or 200 {micro}m core fiber, light from a light emitting diode (LED) is sufficient to operate the sensor. In addition, LEDs ensure that no birefringence effects in the input fiber are possible, as the output from such light sources have random polarization. No lens is required since the large diameter optical fibers and thin crystals of materials having high Verdet constants (such as iron garnets) employed permit the collection of a substantial quantity of light. No coupler is required. The maximum amount of light which could reach a detector using a coupler is 25%, while the measured throughput of the fiber-optic bundle without a coupler is about 42%. All of the elements employed in the present sensor are planar, and no particular orientation of these elements is required. The present sensor operates over a wide range of distances from magnetic field sources, and observed signals are large. When a tone wheel is utilized, the signals are independent of wheel speed, and the modulation is observed to be about 75%. No sensitivity to bends in the input or output optical fiber leads was observed. Reliable operation was achieved down to zero frequency, or no wheel rotation. 5 figs.

Veeser, L.R.; Forman, P.R.; Rodriguez, P.J.

1998-02-17T23:59:59.000Z

399

Modeling 18° Water Variability  

Science Conference Proceedings (OSTI)

Variability of 18° Water formation is investigated with an isopycnic-coordinate model of the North Atlantic. A 30-year spinup integration is used as a “control” experiment in which the upper water column in the Sargasso Sea is shown to be in ...

Robert Marsh; Adrian L. New

1996-06-01T23:59:59.000Z

400

Alternative Fuels Data Center: Medium-Speed and Neighborhood Electric  

Alternative Fuels and Advanced Vehicles Data Center (EERE)

Medium-Speed and Medium-Speed and Neighborhood Electric Vehicle (NEV) Definition and Access to Roadways to someone by E-mail Share Alternative Fuels Data Center: Medium-Speed and Neighborhood Electric Vehicle (NEV) Definition and Access to Roadways on Facebook Tweet about Alternative Fuels Data Center: Medium-Speed and Neighborhood Electric Vehicle (NEV) Definition and Access to Roadways on Twitter Bookmark Alternative Fuels Data Center: Medium-Speed and Neighborhood Electric Vehicle (NEV) Definition and Access to Roadways on Google Bookmark Alternative Fuels Data Center: Medium-Speed and Neighborhood Electric Vehicle (NEV) Definition and Access to Roadways on Delicious Rank Alternative Fuels Data Center: Medium-Speed and Neighborhood Electric Vehicle (NEV) Definition and Access to Roadways on Digg

Note: This page contains sample records for the topic "variable speed permanent" 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

Vehicle Technologies Office: Fact #410: February 6, 2006 Maximum Speed  

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

0: February 6, 0: February 6, 2006 Maximum Speed Limits by State, 2005 to someone by E-mail Share Vehicle Technologies Office: Fact #410: February 6, 2006 Maximum Speed Limits by State, 2005 on Facebook Tweet about Vehicle Technologies Office: Fact #410: February 6, 2006 Maximum Speed Limits by State, 2005 on Twitter Bookmark Vehicle Technologies Office: Fact #410: February 6, 2006 Maximum Speed Limits by State, 2005 on Google Bookmark Vehicle Technologies Office: Fact #410: February 6, 2006 Maximum Speed Limits by State, 2005 on Delicious Rank Vehicle Technologies Office: Fact #410: February 6, 2006 Maximum Speed Limits by State, 2005 on Digg Find More places to share Vehicle Technologies Office: Fact #410: February 6, 2006 Maximum Speed Limits by State, 2005 on AddThis.com...

402

GRR/Section 3-TX-d - Lease of Permanent School Fund Land | Open Energy  

Open Energy Info (EERE)

3-TX-d - Lease of Permanent School Fund Land 3-TX-d - Lease of Permanent School Fund Land < GRR Jump to: navigation, search GRR-logo.png GEOTHERMAL REGULATORY ROADMAP Roadmap Home Roadmap Help List of Sections Section 3-TX-d - Lease of Permanent School Fund Land 03-TX-d - Lease of Public School Fund Land (1).pdf Click to View Fullscreen Triggers None specified Click "Edit With Form" above to add content 03-TX-d - Lease of Public School Fund Land (1).pdf Error creating thumbnail: Page number not in range. Error creating thumbnail: Page number not in range. Error creating thumbnail: Page number not in range. Flowchart Narrative This flowchart illustrates the process of leasing Public School Fund (PSF) lands in Texas. The Texas General Land Office (GLO) oversees the leasing process for PSF lands through Title 31 of the Texas Administrative Code

403

Advanced high-speed flywheel energy storage systems for pulsed power application  

E-Print Network (OSTI)

Power systems on modern commercial transportation systems are moving to more electric based equipment, thus improving the reliability of the overall system. Electrical equipment on such systems will include some loads that require very high power for short periods of time, on the order of a few seconds, especially during acceleration and deceleration. The current approach to solving this problem is sizing the electrical grid for peak power, rather than the average. A method to efficiently store and discharge the pulsed power is necessary to eliminate the cost and weight of oversized generation equipment to support the pulsed power needs of these applications. Highspeed Flywheel Energy Storage Systems (FESS) are effectively capable of filling the niche of short duration, high cycle life applications where batteries and ultra capacitors are not usable. In order to have an efficient high-speed FESS, performing three important steps towards the design of the overall system are extremely vital. These steps are modeling, analysis and control of the FESS that are thoroughly investigated in this dissertation. This dissertation establishes a comprehensive analysis of a high-speed FESS in steady state and transient operations. To do so, an accurate model for the complete FESS is derived. State space averaging approach is used to develop DC and small-signal AC models of the system. These models effectively simplify analysis of the FESS and give a strong physical intuition to the complete system. In addition, they result in saving time and money by avoiding time consuming simulations performed by expensive packages, such as Simulink, PSIM, etc. In the next step, two important factors affecting operation of the Permanent Magnet Synchronous Machine (PMSM) implemented in the high-speed FESS are investigated in detail and outline a proper control strategy to achieve the required performance by the system. Next, a novel design algorithm developed by S.P. Bhattacharyya is used to design the control system. The algorithm has been implemented to a motor drive system, for the first time, in this work. Development of the complete set of the current- and speed-loop proportional-integral controller gains stabilizing the system is the result of this implementation. In the last part of the dissertation, based on the information and data achieved from the analysis and simulations, two parts of the FESS, inverter/rectifier and external inductor, are designed and the former one is manufactured. To verify the validity and feasibility of the proposed controller, several simulations and experimental results on a laboratory prototype are presented.

Talebi Rafsanjan, Salman

2008-12-01T23:59:59.000Z

404

Solar wind suprathermal electron Stahl widths across high-speed stream structures  

SciTech Connect

Suprathermal electrons (100-1500 eV) observed in the solar wind typically show a strahl distribution, that is, a beam directed away from the Sun along the magnetic field direction. The strahl width observed at 1 AU is highly variable, ranging from 10-70 degrees. The obsenred finite width of the strahl results from the competition between beam focusing as the interplanetary magnetic field strength drops with distance from the Sun, and pitch-angle scattering as the beam interacts with the solar wind plasma in transit from the sun. Here we examine strahl width, observed with ACE SWEPAM across high-speed stream structures to investigate variations in electron scattering as a function of local plasma characteristics. We find that narrow strahls (less than 20 degrees wide), indicating reduced scattering, are observed within high-speed streams. Narrow strahls are also observed in both very low temperature solar wind, in association with ICMEs. Case studies of high-speed streams typically show the strahl narrowing at the leading edge of the stream. In some cases, the strahl narrows at the reverse shock or pressure wave, in other cases at the stream interface. The narrowing can either occur discontinuously or gradually over a period of hours. Within the high-speed wind, the strahl remains narrow for a period of hours to days, and then gradually broadens. The strahl width is roughly constant at all energies across these structures. For some fraction of high-speed streams, counterstreaming is associated with passage of the corotating interaction region. In these cases, we find the widths of the two counterstreaming beams frequently differ by more than 40 degrees. This dramatic difference in strahl width contrasts with observations in the solar wind as a whole, in which counterstreaming strahls typically differ in width by less than 20 degrees.

Skoug, Ruth M [Los Alamos National Laboratory; Steinberg, John T [Los Alamos National Laboratory; Goodrich, Katherine A [Los Alamos National Laboratory; Anderson, Brett R [DARTMUTH UNIV.

2011-01-03T23:59:59.000Z

405

Jefferson Lab Science Series - The Ultimate Speed  

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

Higgs Boson and Our Life Higgs Boson and Our Life Previous Video (The Higgs Boson and Our Life) Science Series Video Archive Next Video (What Is CEBAF All About?) What Is CEBAF All About? The Ultimate Speed Dr. William Bertozzi - Massachusetts Institute of Technology Sometime in 1962 In his youth, Dr. William Bertozzi, an MIT professor who has long been a leader in experimental nuclear physics using beams of electrons, carried out an experiment in which he explored the relationship between the velocity of electrons and their kinetic energy by measurements over a range of accelerating voltages between 0.5 MeV and 15 MeV. The kinetic energy is measured using calorimetry and the velocity is measured by time-of-flight. This educational film, made in 1962, documents the experiment and shows

406

High Speed AB-Solar Sail  

E-Print Network (OSTI)

The Solar sail is a large thin film used to collect solar light pressure for moving of space apparatus. Unfortunately, the solar radiation pressure is very small about 9 mkN/sq.m at Earth's orbit. However, the light force significantly increases up to 0.2 - 0.35 N/sq.m near the Sun. The author offers his research on a new revolutionary highly reflective solar sail which flyby (after special maneuver) near Sun and attains velocity up to 400 km/sec and reaching far planets of the Solar system in short time or enable flights out of Solar system. New, highly reflective sail-mirror allows avoiding the strong heating of the solar sail. It may be useful for probes close to the Sun and Mercury and Venus. Key words: AB-solar sail, highly reflective solar sail, high speed propulsion.

A. Bolonkin

2007-01-08T23:59:59.000Z

407

Variable laser attenuator  

DOE Patents (OSTI)

The disclosure relates to low loss, high power variable attenuators comprising one or more transmissive and/or reflective multilayer dielectric filters. The attenuator is particularly suitable to use with unpolarized lasers such as excimer lasers. Beam attenuation is a function of beam polarization and the angle of incidence between the beam and the filter and is controlled by adjusting the angle of incidence the beam makes to the filter or filters. Filters are selected in accordance with beam wavelength. 9 figs.

Foltyn, S.R.

1987-05-29T23:59:59.000Z

408

Variable laser attenuator  

SciTech Connect

The disclosure relates to low loss, high power variable attenuators comprng one or more transmissive and/or reflective multilayer dielectric filters. The attenuator is particularly suitable to use with unpolarized lasers such as excimer lasers. Beam attenuation is a function of beam polarization and the angle of incidence between the beam and the filter and is controlled by adjusting the angle of incidence the beam makes to the filter or filters. Filters are selected in accordance with beam wavelength.

Foltyn, Stephen R. (Los Alamos, NM)

1988-01-01T23:59:59.000Z

409

Solar-type Variables  

E-Print Network (OSTI)

The rich acoustic oscillation spectrum in solar-type variables make these stars particularly interesting for studying fluid-dynamical aspects of the stellar interior. I present a summary of the properties of solar-like oscillations, how they are excited and damped and discuss some of the recent progress in using asteroseismic diagnostic techniques for analysing low-degree acoustic modes. Also the effects of stellar-cycle variations in low-mass main-sequence stars are addressed.

Houdek, Gunter

2009-01-01T23:59:59.000Z

410

Errors in all variables  

SciTech Connect

We present a thorough derivation of the posterior for the straight line fit employing the hyper-plane prior. For the example of the parabola we enlarge the scope to nonlinear problems, however simplify it to be solved resembling the straight line solution. Finally we come to the problem of determining the exponents of a scaling law, where in logarithmic form the scaling exponents are linear coefficients of logarithmic variables.

Preuss, R.; Dose, V. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, D-85748 Garching (Germany)

2005-11-23T23:59:59.000Z

411

High Speed/ Low Effluent Process for Ethanol  

Science Conference Proceedings (OSTI)

n this project, BPI demonstrated a new ethanol fermentation technology, termed the High Speed/ Low Effluent (HS/LE) process on both lab and large pilot scale as it would apply to wet mill and/or dry mill corn ethanol production. The HS/LE process allows very rapid fermentations, with 18 to 22% sugar syrups converted to 9 to 11% ethanol ‘beers’ in 6 to 12 hours using either a ‘consecutive batch’ or ‘continuous cascade’ implementation. This represents a 5 to 8X increase in fermentation speeds over conventional 72 hour batch fermentations which are the norm in the fuel ethanol industry today. The ‘consecutive batch’ technology was demonstrated on a large pilot scale (4,800 L) in a dry mill corn ethanol plant near Cedar Rapids, IA (Xethanol Biofuels). The pilot demonstrated that 12 hour fermentations can be accomplished on an industrial scale in a non-sterile industrial environment. Other objectives met in this project included development of a Low Energy (LE) Distillation process which reduces the energy requirements for distillation from about 14,000 BTU/gal steam ($0.126/gal with natural gas @ $9.00 MCF) to as low as 0.40 KW/gal electrical requirements ($0.022/gal with electricity @ $0.055/KWH). BPI also worked on the development of processes that would allow application of the HS/LE fermentation process to dry mill ethanol plants. A High-Value Corn ethanol plant concept was developed to produce 1) corn germ/oil, 2) corn bran, 3) ethanol, 4) zein protein, and 5) nutritional protein, giving multiple higher value products from the incoming corn stream.

M. Clark Dale

2006-10-30T23:59:59.000Z

412

Design and control of multimodal single-legged vehicles with variable geometry reaction wheel arrays  

E-Print Network (OSTI)

of the motor armature with respect to the permanent magnets,motor performance, however, increasing k t (increasing permanent magnet

Schmidt-Wetekam, Christopher

2011-01-01T23:59:59.000Z

413

High Speed Rail in Japan: A Review and Evaluation of the Shinkansen Train  

E-Print Network (OSTI)

~High Speed R~l $~r~s High Speed Rail in Japan: A Review andorregulation. High Speed Rail in Japan: A Review andCALIFORNIA HIGH SPEED RAIL SERIES Working Paper April 1992

Taniguchi, Mamoru

1992-01-01T23:59:59.000Z

414

The Development Effects of High-Speed Rail Stations and Implications for California  

E-Print Network (OSTI)

CALIFORNIA Rail System The CalSpeed research group at theresearch and development, and Figure California High- Speed Rail

Sands, Brian D.

1993-01-01T23:59:59.000Z

415

The WIPP is the nation's first geologic facility designed for permanent disposal of transuranic  

E-Print Network (OSTI)

The WIPP is the nation's first geologic facility designed for permanent disposal of transuranic, New Mexico to dispose of this waste. The TRU waste being disposed at the WIPP is packaged into drums-level waste and spent nuclear fuel. The WIPP has a total capacity of 6.2 million cubic feet of TRU waste

416

A Quick Efficiency-Optimized Scheme for Vector Controlled Permanent Magnet Synchronous Motor Drive  

Science Conference Proceedings (OSTI)

In view of the operation characters of permanent magnet synchronous motor (PMSM) for hybrid electric vehicle (HEV) application, efficiency optimization control strategy is needed to meet the demand of rapidity. A quick efficiency optimized vector control ... Keywords: PMSM, efficiency optimization, HEV, gradient search technique, golden section technique

Xianqing Cao; Liping Fan

2009-07-01T23:59:59.000Z

417

Original article: Overview of analytical models of permanent magnet electrical machines for analysis and design purposes  

Science Conference Proceedings (OSTI)

Generally, accurate modelling of electrical machines requires the use of finite-element method. However, FE analysis is too time consuming, especially at firsts design stages, from the point of view of engineers working in R&D departments in the electrical ... Keywords: Analytical modelling, Electromagnetic analysis, Permanent magnet machines

Huguette Tiegna, Yacine Amara, Georges Barakat

2013-04-01T23:59:59.000Z

418

The integrated design of a permanent-magnet generator for small wind energy conversion system  

Science Conference Proceedings (OSTI)

This paper presents the integrated design, analysis and performance test of a 1.4 kW, radial-flux, permanent-magnet generator applied to small wind energy conversion system (WECS). In a small WECS, the three major components, i.e., turbine, generator ...

Min-Fu Hsieh; Yu-Han Yeh

2012-12-01T23:59:59.000Z

419

ccsd00004205, Calculation of accurate permanent dipole moments of the lowest  

E-Print Network (OSTI)

inhomogeneous external electric #12;elds [18]. Besides, the "`historical"' approach based on photoassociation of molecules with a permanent electric dipole moment (usually labelled as dipolar molecules) using computed the rates for the photoassociation of mixed alkali pairs, and for the susbsequent formation

420

A permanent-magnet rotor for a high-temperature superconducting bearing  

DOE Green Energy (OSTI)

Design, fabrication, and performance, of a 1/3-m dia., 10-kg flywheel rotor with only one bearing is discussed. To achieve low-loss energy storage, the rotor`s segmented-ring permanent-magnet (PM) is optimized for levitation and circumferential homogeneity. The magnet`s carbon composite bands enable practical energy storage.

Mulcahy, T.M.; Hull, J.R.; Uherka, K.L. [Argonne National Lab., IL (United States); Abboud, R.G. [Commonwealth Research Corp., Chicago, IL (United States); Wise, J.H.; Carnegie, D.W. [Pennsylvania State Univ., University Park, PA (United States). Engineering Science

1995-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "variable speed permanent" 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

Ice-Tethered Profiler Measurements of Dissolved Oxygen under Permanent Ice Cover in the Arctic Ocean  

Science Conference Proceedings (OSTI)

Four ice-tethered profilers (ITPs), deployed between 2006 and 2009, have provided year-round dissolved oxygen (DO) measurements from the surface mixed layer to 760-m depth under the permanent sea ice cover in the Arctic Ocean. These ITPs drifted ...

M.-L. Timmermans; R. Krishfield; S. Laney; J. Toole

2010-11-01T23:59:59.000Z

422

Permanent Closure of MFC Biodiesel Underground Storage Tank 99ANL00013  

SciTech Connect

This closure package documents the site assessment and permanent closure of the Materials and Fuels Complex biodiesel underground storage tank 99ANL00013 in accordance with the regulatory requirements established in 40 CFR 280.71, “Technical Standards and Corrective Action Requirements for Owners and Operators of Underground Storage Tanks: Out-of-Service UST Systems and Closure.”

Kerry L. Nisson

2012-10-01T23:59:59.000Z

423

Design and optimization strategies for muscle-like direct-drive linear permanent-magnet motors  

Science Conference Proceedings (OSTI)

We report a new approach to the design of direct-drive linear permanent-magnet motors for use in general-purpose robotic actuation, with particular attention to applications in bird-scale flapping-wing robots. We show a simple, quantitative analytical ... Keywords: Actuator design, electric motors, muscle

Bryan P Ruddy; Ian W Hunter

2011-06-01T23:59:59.000Z

424

Method and apparatus for sensorless operation of brushless permanent magnet motors  

DOE Patents (OSTI)

A sensorless method and apparatus for providing commutation timing signals for a brushless permanent magnet motor extracts the third harmonic back-emf of a three-phase stator winding and independently cyclically integrates the positive and negative half-cycles thereof and compares the results to a reference level associated with a desired commutation angle.

Sriram, Tillasthanam V. (Carmel, IN)

1998-01-01T23:59:59.000Z

425

An Observer-Based Design for Cogging Forces Cancellation in Permanent Magnet Linear Motors  

E-Print Network (OSTI)

An Observer-Based Design for Cogging Forces Cancellation in Permanent Magnet Linear Motors Jérémy magnet (PM) linear motors, in presence of spatially periodic forces, also known as cogging. Using cleanliness of operation and better resistance to wear and tear. Ironless motors feature two magnetic tracks

Paris-Sud XI, Université de

426

A robust forced dynamic sliding mode minimum energy position controller for permanent magnet synchronous motor drives  

Science Conference Proceedings (OSTI)

As a contribution towards improving the environment, a new position controller for vector controlled electric drives employing permanent magnet synchronous motors (PMSM) is presented that achieves approximately 27% less frictional energy loss than a ... Keywords: forced dynamic control, minimum energy manoeuvres, sliding mode control, synchronous motor drives

Stephen J. Dodds; Gunaratnam. Sooriyakumar; Roy Perryman

2008-04-01T23:59:59.000Z

427

Intelligent control for permanent magnet synchronous motor with improved particle swarm optimization  

Science Conference Proceedings (OSTI)

This paper presents a new intelligent controller for a permanent-magnet synchronous machine in a HEV (hybrid-electric vehicle) application. IPSO (Improved Particle Swarm Optimization) will be used to optimize three proportional parameters ka, ... Keywords: FLC, HEV, IPSO, PMSM, optimization, robustness

Song Zhengqiang; Hou Zhijian; Jiang Chuanwen

2005-09-01T23:59:59.000Z

428

Method and apparatus for sensorless operation of brushless permanent magnet motors  

DOE Patents (OSTI)

A sensorless method and apparatus for providing commutation timing signals for a brushless permanent magnet motor extracts the third harmonic back-emf of a three-phase stator winding and independently cyclically integrates the positive and negative half-cycles thereof and compares the results to a reference level associated with a desired commutation angle. 23 figs.

Sriram, T.V.

1998-04-14T23:59:59.000Z

429

Generation and Stability of a Quasi-Permanent Vortex in the Lofoten Basin  

Science Conference Proceedings (OSTI)

In the Nordic seas the Lofoten Basin is a region of high mesoscale activity. The generation mechanism and the conditions for the stability of a quasi-permanent vortex in the center of the Lofoten Basin are studied with a high-resolution ocean ...

Armin Köhl

2007-11-01T23:59:59.000Z

430

Design of Vertical Transportation System Driven by Permanent Magnet Linear Synchronous Motor Signal Acquisition  

Science Conference Proceedings (OSTI)

Permanent Magnet Linear Synchronous Motor(PMLSM) Vertical Transportation system is a new kind of ropeless hoisting system. In addition to the complications of dynamic state characteristic, the examination of some signals is also very difficult. In this ... Keywords: PMLSM, Signal Acquisition, Hardware Designs, Software

Wang Chang Li; Zhang You Dong; Zhao Liang

2012-08-01T23:59:59.000Z

431

Effect of Casting Speed on Temperature Difference between Copper ...  

Science Conference Proceedings (OSTI)

DRI Carburization in the Reduction and Transition Zones of a Shaft Furnace MIDREX Type · Effect of Casting Speed on Temperature Difference between ...

432

Speeds and Arrival Times of Solar Transients Approximated by Self ...  

Science Conference Proceedings (OSTI)

Abstract The NASA Solar TErrestrial RElations Observatory (STEREO) mission offered the possibility to forecast the arrival times, speeds, and directions of solar  ...

433

United States Wind Resource Map: Annual Average Wind Speed at...  

Wind Powering America (EERE)

and atmospheric effects may cause the wind speed to depart from the map estimates. Expert advice should be sought in placing wind turbines and estimating their energy production....

434

Early Science High Speed Combustion and Detonation Project  

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

Science High Speed Combustion and Detonation Project (HSCD) Alexei Khokhlov, University of Chicago Joanna Austin, University of Illinois Andrew Knisely, University of Illinois...

435

Research moves at the speed of availability | Argonne National...  

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

Centers Science Highlights Postdoctoral Researchers Research moves at the speed of availability October 31, 2012 Tweet EmailPrint Researchers sequence hundreds of genomes across...

436

HIGH-SPEED IMAGER FOR FAST, TRANSIENT EVENTS AT NIF  

Facility. HIGH-SPEED IMAGER . FOR FAST, TRANSIENT ... GATOR can convert x rays and other types of radiation to coherent optical radiation, which can be transported and

437

Extreme Wind Speed Data Sets: Texas Tech/CSU  

Science Conference Proceedings (OSTI)

... B-indicates a beacon tower exposure. ... 93839 Memphis TN 4 3 1968 123 107 WIND SPEEDS GREATER ... [ SED Home | Extreme Winds Home | Data ...

2013-09-27T23:59:59.000Z

438

New process speeds conversion of biomass to fuels  

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

Conversion of Biomass to Fuels New process speeds conversion of biomass to fuels Scientists made a major step forward recently towards transforming biomass-derived molecules into...

439

Special Report: Graphics Processing Units Speed Results in Extreme...  

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

Special Report: Graphics Processing Units Speed Results in Extreme-Scale Supercomputers American Fusion News Category: U.S. Universities Link: Special Report: Graphics Processing...

440

'Slow light' advance could speed optical computing, telecommunications  

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

"Slow light" and specialized metamaterials 'Slow light' advance could speed optical computing, telecommunications Researchers have made the first demonstration of rapidly switching...

Note: This page contains sample records for the topic "variable speed permanent" 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

Discussion of “Ultimate Wind Load Design Gust Wind Speeds ...  

Science Conference Proceedings (OSTI)

... Ind. Aerodyn., 97(3–4), 120–131. Peterka, JA (2001). “Database of peak gust wind speeds, Texas Tech/ CSU.” Extreme winds and wind effects on ...

2013-08-19T23:59:59.000Z

442

High-Speed Fracture Phenomena of Glass Bottle by Underwater ...  

Science Conference Proceedings (OSTI)

Presentation Title, High-Speed Fracture Phenomena of Glass Bottle by Underwater Shock Wave. Author(s), Hidetoshi Sakamoto, Shinjirou Kawabe, Yoshifumi ...

443

Surface wind speed distributions| Implications for climate and wind power.  

E-Print Network (OSTI)

?? Surface constituent and energy fluxes, and wind power depend non-linearly on wind speed and are sensitive to the tails of the wind distribution. Until… (more)

Capps, Scott Blair

2010-01-01T23:59:59.000Z

444

High Speed Rail in Greece : methods for evaluating economic impacts.  

E-Print Network (OSTI)

??High Speed Rail is a mode that gains popularity every day. Many countries have such a network and others are on the way to adopting… (more)

Radopoulou, Stefania Christina

2010-01-01T23:59:59.000Z

445

Jets with Variable R  

E-Print Network (OSTI)

We introduce a new class of jet algorithms designed to return conical jets with a variable Delta R radius. A specific example, in which Delta R scales as 1/pT, proves particularly useful in capturing the kinematic features of a wide variety of hard scattering processes. We implement this Delta R scaling in a sequential recombination algorithm and test it by reconstructing resonance masses and kinematic endpoints. These test cases show 10-20% improvements in signal efficiency compared to fixed Delta R algorithms. We also comment on cuts useful in reducing continuum jet backgrounds.

David Krohn; Jesse Thaler; Lian-Tao Wang

2009-03-02T23:59:59.000Z

446

IEEE TRANSACTIONS ON MAGNETICS, VOL. 42, NO. 7, JULY 2006 1861 Analytical Design of Permanent-Magnet  

E-Print Network (OSTI)

(PM) traction-drive motors with emphasis on calculation of the magnet's volume and size. The method, optimization, permanent magnets (PMs), PM motors, sizing, traction drives, volume. I. INTRODUCTION PERMANENT-MAGNET the designer to choose the sizes of magnets. The performance of the PM motor can be made satisfactory

Mi, Chunting "Chris"

447

Study on Control of Bearingless Permanent Magnet-Type Motor Synchronous Based on Fuzzy Adaptive Sliding Mode  

Science Conference Proceedings (OSTI)

The bearingless permanent magnet-types synchronous motor is nonlinear and coupling complex system. On the basis of the full formula which express the coupling between suspension and rotor torque, parameters of the motor are discussed to the operation ... Keywords: bearingless permanent magnet-type synchronous motor, fuzzy adaptivity, sliding mode, chattering

Pengfei Li; Xinping Yan; Bo Yang; Huabin Wang

2010-05-01T23:59:59.000Z

448

Maximization of No-Load Flux Density in Surface Mounted Permanent Magnet Motors Frdric DUBAS, Christophe ESPANET & Abdellatif MIRAOUI.  

E-Print Network (OSTI)

Maximization of No-Load Flux Density in Surface Mounted Permanent Magnet Motors Frédéric DUBAS mounted permanent magnet motors having a direction of parallel or radial magnetization [1]. I expression of the optimal thickness of the magnet which make it possible to maximize the no-load flux density

Paris-Sud XI, Université de

449

Thermal-Electromagnetic Analysis of a Fault-Tolerant Dual Star Flux-Switching Permanent Magnet Motor for Critical  

E-Print Network (OSTI)

of a fault-tolerant dual star Flux-Switching Permanent Magnet (FSPM) motor. The analytical results in terms permanent magnet motors have attracted increasing attentions in safety critical applications such as Hybrid, the phases of the motors are magnetically and physically separated. Thus, the phase failures (short

Paris-Sud XI, Université de

450

Study of Various Slanted Air-gap Structures of Interior Permanent Magnet Synchronous Motor with Brushless Field Excitation  

E-Print Network (OSTI)

Study of Various Slanted Air-gap Structures of Interior Permanent Magnet Synchronous Motor of the slanted air-gap structure of an interior permanent magnet synchronous motor with brushless field magnet machine, synchronous motors, torque. I. NOMENCLATURE BFE brushless field excitation IPMSM interior

Tolbert, Leon M.

451

A peak power tracker for low-power permanent-magnet-synchronous-generator-based wind energy conversion systems  

Science Conference Proceedings (OSTI)

This paper presents the results of experimental investigation of a low-power wind energy conversion system (WECS), based on a permanent-magnet synchronous generator (PMSG) connected directly to the turbine. A test rig was built in order to carry out ... Keywords: hardware-in-the-loop simulation, maximum power point tracking, optimal control, permanent-magnet synchronous generator, wind system

C. Vlad; I. Munteanu; A. I. Bratcu; E. Ceanga

2008-07-01T23:59:59.000Z

452

Solar Irradiance Variability  

E-Print Network (OSTI)

The Sun has long been considered a constant star, to the extent that its total irradiance was termed the solar constant. It required radiometers in space to detect the small variations in solar irradiance on timescales of the solar rotation and the solar cycle. A part of the difficulty is that there are no other constant natural daytime sources to which the Sun's brightness can be compared. The discovery of solar irradiance variability rekindled a long-running discussion on how strongly the Sun affects our climate. A non-negligible influence is suggested by correlation studies between solar variability and climate indicators. The mechanism for solar irradiance variations that fits the observations best is that magnetic features at the solar surface, i.e. sunspots, faculae and the magnetic network, are responsible for almost all variations (although on short timescales convection and p-mode oscillations also contribute). In spite of significant progress important questions are still open. Thus there is a debat...

Solanki, Sami K

2012-01-01T23:59:59.000Z

453

Low Wind Speed Technology Phase I: Prototype Multi-Megawatt Low Wind Speed Turbine; General Electric Wind Energy, LLC  

SciTech Connect

This fact sheet describes a subcontract with GE Wind Energy to develop an advanced prototype turbine to significantly reduce energy costs (COE) in low wind speed environments.

2006-03-01T23:59:59.000Z

454

High speed point derivative microseismic detector  

DOE Patents (OSTI)

A high speed microseismic event detector constructed in accordance with the present invention uses a point derivative comb to quickly and accurately detect microseismic events. Compressional and shear waves impinging upon microseismic receiver stations disposed to collect waves are converted into digital data and analyzed using a point derivative comb including assurance of quiet periods prior to declaration of microseismic events. If a sufficient number of quiet periods have passed, the square of a two point derivative of the incoming digital signal is compared to a trip level threshold exceeding the determined noise level to declare a valid trial event. The squaring of the derivative emphasizes the differences between noise and signal, and the valid event is preferably declared when the trip threshold has been exceeded over a temporal comb width to realize a comb over a given time period. Once a trial event has been declared, the event is verified through a spatial comb, which applies the temporal event comb to additional stations. The detector according to the present invention quickly and accurately detects initial compressional waves indicative of a microseismic event which typically exceed the ambient cultural noise level by a small amount, and distinguishes the waves from subsequent larger amplitude shear waves. 9 figs.

Uhl, J.E.; Warpinski, N.R.; Whetten, E.B.

1998-06-30T23:59:59.000Z

455

High speed point derivative microseismic detector  

DOE Patents (OSTI)

A high speed microseismic event detector constructed in accordance with the present invention uses a point derivative comb to quickly and accurately detect microseismic events. Compressional and shear waves impinging upon microseismic receiver stations disposed to collect waves are converted into digital data and analyzed using a point derivative comb including assurance of quiet periods prior to declaration of microseismic events. If a sufficient number of quiet periods have passed, the square of a two point derivative of the incoming digital signal is compared to a trip level threshold exceeding the determined noise level to declare a valid trial event. The squaring of the derivative emphasizes the differences between noise and signal, and the valid event is preferably declared when the trip threshold has been exceeded over a temporal comb width to realize a comb over a given time period. Once a trial event has been declared, the event is verified through a spatial comb, which applies the temporal event comb to additional stations. The detector according to the present invention quickly and accurately detects initial compressional waves indicative of a microseismic event which typically exceed the ambient cultural noise level by a small amount, and distinguishes the waves from subsequent larger amplitude shear waves.

Uhl, James Eugene (Albuquerque, NM); Warpinski, Norman Raymond (Albuquerque, NM); Whetten, Ernest Blayne (Albuquerque, NM)

1998-01-01T23:59:59.000Z

456

High speed curved position sensitive detector  

DOE Patents (OSTI)

A high speed curved position sensitive porportional counter detector for use in x-ray diffraction, the detection of 5-20 keV photons and the like. The detector employs a planar anode assembly of a plurality of parallel metallic wires. This anode assembly is supported between two cathode planes, with at least one of these cathode planes having a serpentine resistive path in the form of a meander having legs generally perpendicular to the anode wires. This meander is produced by special microelectronic fabrication techniques whereby the meander "wire" fans outwardly at the cathode ends to produce the curved aspect of the detector, and the legs of the meander are small in cross-section and very closely spaced whereby a spatial resolution of about 50 .mu.m can be achieved. All of the other performance characteristics are about as good or better than conventional position sensitive proportional counter type detectors. Count rates of up to 40,000 counts per second with 0.5 .mu.s shaping time constants are achieved.

Hendricks, Robert W. (Montgomery County, VA); Wilson, Jack W. (Knox County, TN)

1989-01-01T23:59:59.000Z

457

Climate Variability, Fish, and Fisheries  

Science Conference Proceedings (OSTI)

Fish population variability and fisheries activities are closely linked to weather and climate dynamics. While weather at sea directly affects fishing, environmental variability determines the distribution, migration, and abundance of fish. ...

P. Lehodey; J. Alheit; M. Barange; T. Baumgartner; G. Beaugrand; K. Drinkwater; J.-M. Fromentin; S. R. Hare; G. Ottersen; R. I. Perry; C. Roy; C. D. van der Lingen; F. Werner

2006-10-01T23:59:59.000Z

458

Colorado River Basin Hydroclimatic Variability  

Science Conference Proceedings (OSTI)

An analysis of annual hydroclimatic variability in the Upper Colorado River basin (UCRB) for the period of 1906–2006 was performed to understand the dominant modes of multidecadal variability. First, wavelet-based spectral analysis was employed ...

Kenneth Nowak; Martin Hoerling; Balaji Rajagopalan; Edith Zagona

2012-06-01T23:59:59.000Z

459

Scalable analysis of variable software  

Science Conference Proceedings (OSTI)

The advent of variability management and generator technology enables users to derive individual variants from a variable code base based on a selection of desired configuration options. This approach gives rise to the generation of possibly billions ... Keywords: C Preprocessor, Liveness Analysis, Software Product Lines, Type Checking, Variability-aware Analysis

Jörg Liebig; Alexander von Rhein; Christian Kästner; Sven Apel; Jens Dörre; Christian Lengauer

2013-08-01T23:59:59.000Z

460

Variability within Modeling Language Definitions  

Science Conference Proceedings (OSTI)

We present a taxonomy of the variability mechanisms offered by modeling languages. The definition of a formal language encompasses a syntax and a semantic domain as well as the mapping that relates them, thus language variabilities are classified according ... Keywords: Modeling languages, UML, formal semantics, variability

María Victoria Cengarle; Hans Grönniger; Bernhard Rumpe

2009-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "variable speed permanent" 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

Symmetrization Of Binary Random Variables  

E-Print Network (OSTI)

A random variable Y is called an independent symmetrizer of a given random variable X if (a) it is independent of X and (b) the distribution of X Y is symmetric about 0. In cases where the distribution of X is symmetric about its mean, it is easy to see that the constant random variable Y is a minimum-variance independent symmetrizer. Taking

Abram Kagan; Colin Mallows; Larry Shepp; Robert J. Vanderbei; Yehuda Vardi

1999-01-01T23:59:59.000Z

462

Proposed high speed packet switch for broadband integrated networks  

Science Conference Proceedings (OSTI)

The design of a high speed, broadband packet switch with two priority levels for application in integrated voice/data networks is presented. The packet switch can efficiently cope with 128 byte packets converging on it from eight 140 Mbit/s dynamic time ... Keywords: backbone network, broadband integrated services digital networks, high speed packet switch, voice/data integration

Krishna Thilakam; Ashok Jhunjhunwala

1989-12-01T23:59:59.000Z

463

Ocean Wind Speed Climatology from Spaceborne SAR Imagery  

Science Conference Proceedings (OSTI)

Spaceborne synthetic aperture radar (SAR) imagery can make high-resolution (? 500 m) ocean wind speed measurements. We anticipate re-processing the full decade and a half of Radarsat-1 SAR imagery and generating a SAR wind speed archive. These data will ...

Frank M. Monaldo; Xiaofeng Li; William G. Pichel; Christopher R. Jackson

464

Turbine speed control for an ocean wave energy conversion system  

Science Conference Proceedings (OSTI)

In this work, a hydraulic turbine speed governor is proposed in view of its application in an isolated electric generation system based on an ocean wave energy converter (WEC). The proposed strategy is based on cascade closed-loop control combined with ... Keywords: Pelton turbine, cascade control, feedforward control, ocean wave energy, speed governor

Paula B. Garcia-Rosa; José Paulo V. S. Cunha; Fernando Lizarralde

2009-06-01T23:59:59.000Z

465

Estimation of Extreme Wind Speeds with Very Long Return Periods  

Science Conference Proceedings (OSTI)

Long series of hourly mean wind speeds and the maximum hourly 3-s gust are simulated for four sites in the British Isles in order to investigate methods for the determination of extreme wind speed events. The simulation is performed using a one-...

M. D. G. Dukes; J. P. Palutikof

1995-09-01T23:59:59.000Z

466

High speed flow cytometric separation of viable cells  

SciTech Connect

Hematopoietic cell populations are separated to provide cell sets and subsets as viable cells with high purity and high yields, based on the number of original cells present in the mixture. High-speed flow cytometry is employed using light characteristics of the cells to separate the cells, where high flow speeds are used to reduce the sorting time.

Sasaki, Dennis T. (Mountain View, CA); Van den Engh, Gerrit J. (Seattle, WA); Buckie, Anne-Marie (Margate, GB)

1995-01-01T23:59:59.000Z

467

High Speed Rail in America Thomas Ducharme, Matt Schena,  

E-Print Network (OSTI)

://m.wikitravel.org/en/Frankfurt #12;Possible effects on Freight Rail · High speed rail usually hauls passengers, though new Resulting in improvement to those lines o Reducing operating costs due to sharing rail · Increase in freightHigh Speed Rail in America Thomas Ducharme, Matt Schena, and Dan Bellis #12;The US Current

Nagurney, Anna

468

High speed flow cytometric separation of viable cells  

DOE Patents (OSTI)

Hematopoietic cell populations are separated to provide cell sets and subsets as viable cells with high purity and high yields, based on the number of original cells present in the mixture. High-speed flow cytometry is employed using light characteristics of the cells to separate the cells, where high flow speeds are used to reduce the sorting time.

Sasaki, D.T.; Van den Engh, G.J.; Buckie, A.M.

1995-11-14T23:59:59.000Z

469

Intelligent acoustic rotor speed estimation for an autonomous helicopter  

Science Conference Proceedings (OSTI)

Acoustic sensing to gather information about a machine can be highly beneficial, but processing the data can be difficult. In this work, a variety of methodologies have been studied to extract rotor speed information from the sound signature of an autonomous ... Keywords: Acoustic sensing, Adaptive network-based fuzzy inference system, Artificial neural network, Feature selection, Genetic algorithm, Helicopter, Rotor speeds

Benjamin N. Passow; Mario A. Gongora; Adrian A. Hopgood; Sophy Smith

2012-11-01T23:59:59.000Z

470

Routing for power minimization in the speed scaling model  

Science Conference Proceedings (OSTI)

We study network optimization that considers power minimization as an objective. Studies have shown that mechanisms such as speed scaling can significantly reduce the power consumption of telecommunication networks by matching the consumption of each ... Keywords: power saving, routing, speed scaling, wireline networks

Matthew Andrews; Antonio Fernández Anta; Lisa Zhang; Wenbo Zhao

2012-02-01T23:59:59.000Z

471

Information transmittal and time uncertainty, measuring the speed of light and time of reflection, representations of Newton's second law and related problems  

Science Conference Proceedings (OSTI)

Some physical and computational aspects related to the intuitive notion of time in its connection with natural and technological processes are considered. The phenomenon of finite speed of information transmittal relative to measurement and computation ... Keywords: Forces with left higher order derivatives, Information transmittal, Measurements and computations, Mirror reflection, Time uncertainty, Variable mass

E. A. Galperin

2008-09-01T23:59:59.000Z

472

New simulation speed record set on Sequoia | National Nuclear Security  

National Nuclear Security Administration (NNSA)

New simulation speed record set on Sequoia | National Nuclear Security New simulation speed record set on Sequoia | 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 > NNSA Blog > New simulation speed record set on Sequoia New simulation speed record set on Sequoia Posted By Office of Public Affairs New simulation speed record set on Sequoia Computer scientists at Lawrence Livermore National Laboratory and

473

Preservation of and permanent access to electronic information resources: A system perspective  

Science Conference Proceedings (OSTI)

The rapid growth in the creation and dissemination of electronic information has emphasized the digital environment's speed and ease of dissemination often with little regard for its long-term preservation and access. But, electronic information is fragile ...

Gail Hodge

2005-01-01T23:59:59.000Z

474

Radiation-Induced Demagnetization of Nd-Fe-B Permanent Magnets  

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

LS-290 LS-290 Radiation-Induced Demagnetization of Nd-Fe-B Permanent Magnets J. Alderman and P.K. Job APS Operations Division Advanced Photon Source Argonne National Laboratory R.C. Martin, C.M. Simmons, and G.D. Owen Californium User Facility for Neutron Science Chemical Technology Division Oak Ridge National Laboratory J. Puhl Ionizing Radiation Division National Institute of Standards and Technology November 2000 work sponsored by U.S. DEPARTMENT OF ENERGY Office of Energy Research 1 Radiation-Induced Demagnetization of Nd-Fe-B Permanent Magnets J. Alderman and P.K. Job APS Operations Division Advanced Photon Source Argonne National Laboratory R.C. Martin, C.M. Simmons, and G. D. Owen Californium User Facility for Neutron Science

475

Adjustable Permanent Quadrupoles Using Rotating Magnet Material Rods for the Next Linear Collider  

Science Conference Proceedings (OSTI)

The proposed Next Linear Collider (NLC) will require over 1400 adjustable quadrupoles between the main linacs' accelerator structures. These 12.7 mm bore quadrupoles will have a range of integrated strength from 0.6 to 132 Tesla, with a maximum gradient of 135 Tesla per meter, an adjustment range of +0-20% and effective lengths from 324 mm to 972 mm. The magnetic center must remain stable to within 1 micrometer during the 20% adjustment. In an effort to reduce estimated costs and increase reliability, several designs using hybrid permanent magnets have been developed. All magnets have iron poles and use either Samarium Cobalt or Neodymium Iron to provide the magnetic fields. Two prototypes use rotating rods containing permanent magnetic material to vary the gradient. Gradient changes of 20% and center shifts of less than 20 microns have been measured. These data are compared to an equivalent electromagnet prototype.

James T Volk et al.

2001-09-24T23:59:59.000Z

476

An Airbreathing Launch Vehicle Design with Turbine-Based Low-Speed Propulsion and Dual Mode Scramjet High-Speed Propulsion  

E-Print Network (OSTI)

Airbreathing launch vehicles continue to be a subject of great interest in the space access community. In particular, horizontal takeoff and horizontal landing vehicles are attractive with their airplane-like benefits and flexibility for future space launch requirements. The most promising of these concepts involve airframe integrated propulsion systems, in which the external undersurface of the vehicle forms part of the propulsion flowpath. Combining of airframe and engine functions in this manner involves all of the design disciplines interacting at once. Design and optimization of these configurations is a most difficult activity, requiring a multi-discipline process to analytically resolve the numerous interactions among the design variables. This paper describes the design and optimization of one configuration in this vehicle class, a lifting body with turbine-based low-speed propulsion. The integration of propulsion and airframe, both from an aero-propulsive and mechanical perspe...

Moses Bouchard Vause; L. W. Taylor Lll; P. L. Moses; P. L. Moses; K. A. Bouchard; K. A. Bouchard; R. F. Vause; R. F. Vause; S. Z. Pinckney; S. Z. Pinckney; L. W. Taylor Iii; S. M. Ferlemann; S. M. Ferlemann; C. P. Leonard; C. P. Leonard; J. S. Robinson; J. S. Robinson; J. G. Martin; J. G. Martin; D. H. Petley; D. H. Petley; J. L. Hunt; J. L. Hunt

1999-01-01T23:59:59.000Z

477

Axial Flux, Modular, Permanent-Magnet Generator with a Toroidal Winding for Wind Turbine Applications  

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

CP-500-24996 Ÿ UC Category: 1213 CP-500-24996 Ÿ UC Category: 1213 Axial Flux, Modular, Permanent- Magnet Generator with a Toroidal Winding for Wind Turbine Applications E. Muljadi C.P. Butterfield Yih-Huei Wan National Wind Technology Center National Renewable Energy Laboratory Presented at IEEE Industry Applications Conference St. Louis, MO November 5-8, 1998 National Renewable Energy Laboratory 1617 Cole Boulevard

478

Environmental radiation real-time monitoring system permanently installed near Qinshan Nuclear Power Plant  

SciTech Connect

An environmental radiation real-time monitoring system with high pressure ionization chamber was developed. It has been installed permanently in the vicinity of Qinshan Nuclear Power Plant, the first built in mainland China. The system consists of four basic components: environmental radiation monitors; data communication network; a data processing center; and a remote terminal computer situated in Hangzhou. It has provided five million readings of environmental radiation levels as of January 1993. 8 refs., 1 fig., 3 tabs.

Minde Ding; Peiru Sheng; Zhangji Zhi [Suzhou Nuclear Research Institute, Jiangsu (China)

1996-03-01T23:59:59.000Z

479

A safety and regulatory assessment of generic BWR and PWR permanently shutdown nuclear power plants  

SciTech Connect

The long-term availability of less expensive power and the increasing plant modification and maintenance costs have caused some utilities to re-examine the economics of nuclear power. As a result, several utilities have opted to permanently shutdown their plants. Each licensee of these permanently shutdown (PSD) plants has submitted plant-specific exemption requests for those regulations that they believe are no longer applicable to their facility. This report presents a regulatory assessment for generic BWR and PWR plants that have permanently ceased operation in support of NRC rulemaking activities in this area. After the reactor vessel is defueled, the traditional accident sequences that dominate the operating plant risk are no longer applicable. The remaining source of public risk is associated with the accidents that involve the spent fuel. Previous studies have indicated that complete spent fuel pool drainage is an accident of potential concern. Certain combinations of spent fuel storage configurations and decay times, could cause freshly discharged fuel assemblies to self heat to a temperature where the self sustained oxidation of the zircaloy fuel cladding may cause cladding failure. This study has defined four spent fuel configurations which encompass all of the anticipated spent fuel characteristics and storage modes following permanent shutdown. A representative accident sequence was chosen for each configuration. Consequence analyses were performed using these sequences to estimate onsite and boundary doses, population doses and economic costs. A list of candidate regulations was identified from a screening of 10 CFR Parts 0 to 199. The continued applicability of each regulation was assessed within the context of each spent fuel storage configuration and the results of the consequence analyses.

Travis, R.J.; Davis, R.E.; Grove, E.J.; Azarm, M.A. [Brookhaven National Lab., Upton, NY (United States)

1997-08-01T23:59:59.000Z

480

Dynamic high pressure process for fabricating superconducting and permanent magnetic materials  

DOE Patents (OSTI)

Shock wave formation of thin layers of materials with improved superconducting and permanent magnetic properties and improved microstructures is disclosed. The material fabrication system includes a sandwiched structure including a powder material placed between two solid members to enable explosive shock consolidation. The two solid members are precooled to about 80--100 K to reduce the residual temperatures attained as a result of the shock wave treatment, and thereby increase the quench rate of the consolidated powder. 9 figs.

Nellis, W.J.; Geballe, T.H.; Maple, M.B.

1990-03-13T23:59:59.000Z

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


481

Dynamic high pressure process for fabricating superconducting and permanent magnetic materials  

DOE Patents (OSTI)

Shock wave formation of thin layers of materials with improved superconducting and permanent magnetic properties and improved microstructures. The material fabrication system includes a sandwiched structure including a powder material placed between two solid members to enable explosive shock consolidation. The two solid members are precooled to about 80.degree.-100.degree. K. to reduce the residual temperatures attained as a result of the shock wave treatment, and thereby increase the quench rate of the consolidated powder.

Nellis, William J. (Berkeley, CA); Geballe, Theodore H. (Woodside, CA); Maple, M. Brian (Del Mar, CA)

1990-01-01T23:59:59.000Z

482

Evaluation of an Advanced Radiation Shielding Material for Permanent Installation at an Operating Commercial Nuclear Reactor  

Science Conference Proceedings (OSTI)

The industry continues to investigate, validate, and implement new radiation field reduction measures in response to increased emphasis on reducing dose to workers. Many nuclear plants are interested in permanent shielding applications to further reduce personnel exposure and to reduce the recurring effort associated with temporary installations. In 2008, a flexible, impregnated, layered matrix material was identified as a possible material for incorporating a shielding substance. This report provides an...

2010-09-30T23:59:59.000Z

483

The use of a permanent magnet for water content measurements ofwood chips  

Science Conference Proceedings (OSTI)

The Lawrence Berkeley National Laboratory has developed a device that measures the water content of wood chips, pulp and brown stock for the paper industry. This device employs a permanent magnet as the central part of a NMR measurement system. This report describes the magnet and the NMR measurement system. The results of water content measurements in wood chips in a magnetic field of 0.47 T are presented.

Barale, P.J.; Fong, C.G.; Green, M.A.; Luft, P.A.; McInturff,A.D.; Reimer, J.A.; Yahnke, M.

2001-09-20T23:59:59.000Z

484

Permanent alterations in muscarinic receptors and pupil size produced by chronic atropinization in kittens  

SciTech Connect

Chronic mydriasis was induced in six kittens (four monocular, two binocular) and two adult cats (both monocular) by the daily topical application of atropine. Both the kittens and the adult cats were atropinized for a 13-week period with the treatment regimen beginning at the time of eye opening for the kittens. Pupil size measurements, obtained 1 year after the atropinization were discontinued, revealed that, although the pupils of the adult cats were normal, the pupils of the kittens' treated eyes were consistently smaller than pupils in control eyes. The status of the muscarinic receptors in the kittens' irides was investigated using /sup 3/H-QNB binding assays. In comparison with iris muscle homogenates from the control eyes, those from the treated eyes demonstrated an eightfold increase in the number of receptor binding sites. The results indicate that pupil size can be altered permanently by chronic mydriasis initiated early in the life of a kitten and that the permanent change in pupil size may result, in part, from a type of permanent supersensitivity response in the muscle following chronic blockade of muscarinic transmission by atropine.

Smith, E.L.; Redburn, D.A.; Harwerth, R.S.; Maguire, G.W.

1984-02-01T23:59:59.000Z

485

Development of Piagetian object permanence in a Grey parrot (Psittacus erithacus  

E-Print Network (OSTI)

The authors evaluated the ontogenetic performance of a grey parrot (Psittacus erithacus) on object permanence tasks designed for human infants. Testing began when the bird was 8 weeks old, prior to fledging and weaning. Because adult grey parrots understand complex invisible displacements (I. M. Pepperberg & F. A. Kozak, 1986), the authors continued weekly testing until the current subject completed all of I. C. Uzgiris and J. Hunt's (1975) Scale 1 tasks. Stage 6 object permanence with respect to these tasks emerged at 22 weeks, after the bird had fledged but before it was completely weaned. Although the parrot progressed more rapidly overall than other species that have been tested ontogenetically, the subject similarly exhibited a behavioral plateau part way through the study. Additional tests, administered at 8 and 12 months as well as to an adult grey parrot, demonstrated, respectively, that these birds have some representation of a hidden object and understand advanced invisible displacements. In children, object permanence—the notion that objects are separate entities that continue to exist when out of sight of the observer—is neither innate nor unitary, but develops

Mark R. Willner; Lauren B. Gravitz; Mark R. Willner; Department Of Ecology

1997-01-01T23:59:59.000Z

486

Spatial and Temporal Patterns of Global Onshore Wind Speed Distribution  

SciTech Connect

Wind power, a renewable energy source, can play an important role in electrical energy generation. Information regarding wind energy potential is important both for energy related modeling and for decision-making in the policy community. While wind speed datasets with high spatial and temporal resolution are often ultimately used for detailed planning, simpler assumptions are often used in analysis work. An accurate representation of the wind speed frequency distribution is needed in order to properly characterize wind energy potential. Using a power density method, this study estimated global variation in wind parameters as fitted to a Weibull density function using NCEP/CFSR reanalysis data. The estimated Weibull distribution performs well in fitting the time series wind speed data at the global level according to R2, root mean square error, and power density error. The spatial, decadal, and seasonal patterns of wind speed distribution were then evaluated. We also analyzed the potential error in wind power estimation when a commonly assumed Rayleigh distribution (Weibull k = 2) is used. We find that the assumption of the same Weibull parameter across large regions can result in substantial errors. While large-scale wind speed data is often presented in the form of average wind speeds, these results highlight the need to also provide information on the wind speed distribution.

Zhou, Yuyu; Smith, Steven J.

2013-09-09T23:59:59.000Z

487

arXiv:1103.2923v1[math.OC]15Mar2011 Estimation of Saturation of Permanent-Magnet  

E-Print Network (OSTI)

arXiv:1103.2923v1[math.OC]15Mar2011 Estimation of Saturation of Permanent-Magnet Synchronous Motors a parametric model of the saturated Permanent-Magnet Synchronous Motor (PMSM) together with an estimation: Permanent magnet synchronous motor, mag- netic circuit modeling, magnetic saturation, energy-based mod

Paris-Sud XI, Université de

488

Abstract --This paper deals a double layer and a single layer Flux-Switching Permanent Magnet (FSPM) motors for a fault  

E-Print Network (OSTI)

-Switching Permanent Magnet (FSPM) motors attract more and more attentions in the critical application as the Hybrid motor. DOUBLE AND SINGLE LAYERS FLUX-SWITCHING PERMANENT MAGNET MOTORS: FAULT TOLERANT MODELAbstract --This paper deals a double layer and a single layer Flux-Switching Permanent Magnet (FSPM

Paris-Sud XI, Université de

489

Vermont Standard Offer for Qualifying SPEED Resources | Department of  

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

Vermont Standard Offer for Qualifying SPEED Resources Vermont Standard Offer for Qualifying SPEED Resources Vermont Standard Offer for Qualifying SPEED Resources < Back Eligibility Agricultural Commercial Industrial Savings Category Bioenergy Water Buying & Making Electricity Solar Home Weatherization Wind Maximum Rebate Varies by technology Program Info Start Date 09/30/2009 State Vermont Program Type Performance-Based Incentive Rebate Amount Varies by technology Provider VEPP, Inc. '''''Note: The first RFP for the new competitive award process has passed; applications were accepted through May 1, 2013. See the program web site for information regarding future solicitations. ''''' In May 2009, Vermont enacted legislation requiring all Vermont retail electricity providers to purchase electricity generated by eligible

490

Coal-fueled high-speed diesel engine development  

DOE Green Energy (OSTI)

The objectives of this program are to study combustion feasibility by running Series 149 engine tests at high speeds with a fuel injection and combustion system designed for coal-water-slurry (CWS). The following criteria will be used to judge feasibility: (1) engine operation for sustained periods over the load range at speeds from 600 to 1900 rpm. The 149 engine for mine-haul trucks has a rated speed of 1900 rpm; (2) reasonable fuel economy and coal burnout rate; (3) reasonable cost of the engine design concept and CWS fuel compared to future oil prices.

Not Available

1991-11-01T23:59:59.000Z

491

Short-Term Wind Speed Forecasting for Power System Operations  

E-Print Network (OSTI)

Global large scale penetration of wind energy is accompanied by significant challenges due to the intermittent and unstable nature of wind. High quality short-term wind speed forecasting is critical to reliable and secure power system operations. This paper gives an overview of the current status of worldwide wind power developments and future trends, and reviews some statistical short-term wind speed forecasting models, including traditional time series models and advanced space-time statistical models. It also discusses the evaluation of forecast accuracy, in particular the need for realistic loss functions. New challenges in wind speed forecasting regarding ramp events and offshore wind farms are also presented.

Xinxin Zhu; Marc G. Genton

2011-01-01T23:59:59.000Z

492

Influence of field potential on the speed of light  

E-Print Network (OSTI)

The paper discusses the affection of the scalar potential on the speed of light in the electromagnetic field, by means of the characteristics of octonion. In the octonion space, the radius vector is combined with the integral of field potentials to become one new radius vector. When the field potentials can not be neglected, the new radius vector will cause the prediction to departure slightly from the theoretical value of the speed of light. The results explain why the speed of light varies in diversiform optical waveguide. And there exist negative refractive indexes due to different scalar potentials in the gravitational field and electromagnetic field.

Zi-Hua Weng

2009-06-07T23:59:59.000Z

493

The constancy, or otherwise, of the speed of light  

E-Print Network (OSTI)

New varying speed of light (VSL) theories as alternatives to the inflationary model of the universe are discussed and evidence for a varying speed of light reviewed. Work linked with VSL but primarily concerned with deriving Planck's black body energy distribution for a gas-like aether using Maxwell statistics is considered also. Doubly Special Relativity, a modification of special relativity to account for observer dependent quantum effects at the Planck scale, is introduced and it is found that a varying speed of light above a threshold frequency is a necessity for this theory.

Daniel J. Farrell; J. Dunning-Davies

2004-06-23T23:59:59.000Z

494

VARIABLE TIME-INTERVAL GENERATOR  

DOE Patents (OSTI)

This patent relates to a pulse generator and more particularly to a time interval generator wherein the time interval between pulses is precisely determined. The variable time generator comprises two oscillators with one having a variable frequency output and the other a fixed frequency output. A frequency divider is connected to the variable oscillator for dividing its frequency by a selected factor and a counter is used for counting the periods of the fixed oscillator occurring during a cycle of the divided frequency of the variable oscillator. This defines the period of the variable oscillator in terms of that of the fixed oscillator. A circuit is provided for selecting as a time interval a predetermined number of periods of the variable oscillator. The output of the generator consists of a first pulse produced by a trigger circuit at the start of the time interval and a second pulse marking the end of the time interval produced by the same trigger circuit.

Gross, J.E.

1959-10-31T23:59:59.000Z

495

CDIAC Climate Data: Available Variables  

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

Climate Variables Available in CDIAC Data Products Temperature Precipitation Cloudiness Sunshine Duration Snowfall and Snow Depth Atmospheric Pressure Atmospheric Moisture Surface...