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We encourage you to perform a real-time search of NLEBeta
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1

Modelling and Control of an Inverted Pendulum Turbine  

E-Print Network [OSTI]

Modelling and Control of an Inverted Pendulum Turbine Sergi Rotger Griful Kongens Lyngby 2012 IMM. In this project the feasibility of a new kind of wind turbine is studied. This thesis deals with the achievement of getting a proper mathematical model of a new kind of wind turbine, called the inverted pendulum turbine

2

Droop-Controlled Inverters are Kuramoto Oscillators  

E-Print Network [OSTI]

Droop-Controlled Inverters are Kuramoto Oscillators John W. Simpson-Porco Florian D¨orfler Barbara, Santa Barbara, CA 93106, USA, (e-mail: {johnwsimpsonporco,dorfler

Bullo, Francesco

3

Design of a Robust Digital Current Controller for a Grid Connected Interleaved Inverter  

E-Print Network [OSTI]

Design of a Robust Digital Current Controller for a Grid Connected Interleaved Inverter M. A for a three- phase voltage source grid-connected interleaved inverter. Each phase consists of 6 half of electrical sources include fuel cells, solar cells, wind turbines, flywheel, and batteries. Most

4

Model Predictive Control Wind Turbines  

E-Print Network [OSTI]

Model Predictive Control of Wind Turbines Martin Klauco Kongens Lyngby 2012 IMM-MSc-2012-65 #12;Summary Wind turbines are the biggest part of the green energy industry. Increasing interest control strategies. Control strategy has a significant impact on the wind turbine operation on many levels

5

Anticipatory control of turbine generators  

E-Print Network [OSTI]

of Turbine Generators. (Nay 1971) Freddie Laurel Nessec, B. S. E. E, , Texas Tech University; Directed by: Professor J. S . Denison An investigation is made of the use of predicted loads in controlling turbine generators. A perturbation model of a turbine... generator is presented along with typical parameter values. A study is made of the effects of applying control action before a load change occurs. Two predictive control schemes are investi- gated using a load cycle which incorporates both ramp and step...

Messec, Freddie Laurel

1971-01-01T23:59:59.000Z

6

Hybrid Cascaded Multilevel Inverter with PWM Control Method  

E-Print Network [OSTI]

162 Hybrid Cascaded Multilevel Inverter with PWM Control Method Haiwen Liu1 , Leon M. Tolbert1, 2 inverter with PWM method is presented in this paper. It consists of a standard 3-leg inverter (one leg for each phase) and H-bridge in series with each inverter leg. It can use only a single DC power source

Tolbert, Leon M.

7

Maximum Constant Boost Control of the Z-Source Inverter  

E-Print Network [OSTI]

Maximum Constant Boost Control of the Z-Source Inverter Miaosen Shen1 , Jin Wang1 , Alan Joseph1 Laboratory Abstract: This paper proposes two maximum constant boost control methods for the Z-source inverter to modulation index is analyzed in detail and verified by simulation and experiment. Keywords- Z-source inverter

Tolbert, Leon M.

8

Automatic Control of Freeboard and Turbine Operation  

E-Print Network [OSTI]

Automatic Control of Freeboard and Turbine Operation ­ Wave Dragon, Nissum Bredning Project: Sea of Freeboard and Turbine Operation Wave Dragon, Nissum Bredning by Jens Peter Kofoed & Peter Frigaard, Aalborg.........................................................................................................................10 TURBINE PERFORMANCE DATA

9

A Fatigue Approach to Wind Turbine Control  

E-Print Network [OSTI]

A Fatigue Approach to Wind Turbine Control Keld Hammerum Kongens Lyngby 2006 #12;Technical to the turbulent nature of wind, the structural components of a wind turbine are exposed to highly varying loads. Therefore, fatigue damage is a major consideration when designing wind turbines. The control scheme applied

10

Mono inverter Multi parallel PMSM -Structure and Control strategy  

E-Print Network [OSTI]

Mono inverter Multi parallel PMSM - Structure and Control strategy Damien Bidarta , Maria Pietrzak a new and original Mono inverter Multi parallel Permanent Magnet Synchronous Motor (PMSM) system. Experimental results are given for a system with 2 PMSM plugged in parallel. The proposed solution can however

Boyer, Edmond

11

ADAPTIVE HYSTERESIS CURRENT CONTROL OF INVERTER FOR SOLAR PHOTOVOLTAIC APPLICATIONS  

E-Print Network [OSTI]

Abstract Power inverters are used to convert the D.C power produced by the solar photovoltaic cell into AC. This paper presents a novel Adaptive Hysteresis Current Controller to control the inverter, used in the solar photovoltaic cell. The proposed controller is capable of reducing the total harmonic distortion and to provide constant switching frequency. The mathematical model of Photovoltaic array is developed using the Newtons method using the parameter obtained from a commercial photovoltaic data sheet under variable weather conditions, in which the effect of irradiance and temperature are considered. The modeled Photovoltaic array is interfaced with DC-DC boost converter, AC-DC inverter and load. A DC-DC boost converter is used to step up the input DC voltage of the Photovoltaic array while the DC-AC single-phase inverter converts the input DC comes from boost converter into AC. The performance of the proposed controller of inverter is evaluated through MATLAB-Simulation. The results obtained with the proposed algorithm are compared with those obtained when using conventional fixed hysteresis current controller for single-phase photovoltaic inverter in terms of THD and switching frequency.

unknown authors

2011-01-01T23:59:59.000Z

12

Capacitor Voltage Control in a Cascaded Multilevel Inverter as a Static Var Generator  

E-Print Network [OSTI]

1 Capacitor Voltage Control in a Cascaded Multilevel Inverter as a Static Var Generator M. Li, J. N for a cascaded multilevel inverter to be used for static var compensation. Index Terms-- Multilevel Inverter, Static Var Generator (SVG), Cascade inverter. I. INTRODUCTION Multilevel inverters have gained much

Tolbert, Leon M.

13

Advanced Control Design and Testing for Wind Turbines at the...  

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

Control Design and Testing for Wind Turbines at the National Renewable Energy Laboratory: Preprint Advanced Control Design and Testing for Wind Turbines at the National Renewable...

14

Design and Control of an Inverter for Photovoltaic Applications  

E-Print Network [OSTI]

Design and Control of an Inverter for Photovoltaic Applications by Søren Bækhøj Kjær Dissertation Assistant. He also taught photovoltaic systems for terrestrial- and space-applications (Power system quality, control and optimized design, for fuel cell and photovoltaic applications. He is currently

Hansen, René Rydhof

15

Design considerations for inverters in fluid flow control  

E-Print Network [OSTI]

. 12 PWM spectrum generation 3. 13 Line and phase voltages of PWM inverter 3. 14 PWM output current with Induction Motor 3. 15 Harmonics elimination technique 3. 16 Adaptive PWM with bang-bang control 3. 17 Adaptive PWM control block diagram . 3... output with induction motor load. ~ Sine-triangulation PWM (Sinusoidal PWM) ~ Harmonic Elimination Principle ~ Adaptive Current Control PWM (Hysterisis or Bang-Bang Control) Sine-triangulation PWM The sine-triangulation PWM technique is most widely...

Guggari, Mallappa Ishwarappa

1989-01-01T23:59:59.000Z

16

Active load control techniques for wind turbines.  

SciTech Connect (OSTI)

This report provides an overview on the current state of wind turbine control and introduces a number of active techniques that could be potentially used for control of wind turbine blades. The focus is on research regarding active flow control (AFC) as it applies to wind turbine performance and loads. The techniques and concepts described here are often described as 'smart structures' or 'smart rotor control'. This field is rapidly growing and there are numerous concepts currently being investigated around the world; some concepts already are focused on the wind energy industry and others are intended for use in other fields, but have the potential for wind turbine control. An AFC system can be broken into three categories: controls and sensors, actuators and devices, and the flow phenomena. This report focuses on the research involved with the actuators and devices and the generated flow phenomena caused by each device.

van Dam, C.P. (University of California, Davis, CA); Berg, Dale E.; Johnson, Scott J. (University of California, Davis, CA)

2008-07-01T23:59:59.000Z

17

Vertical axis wind turbine control strategy  

SciTech Connect (OSTI)

Early expensive in automatic operation of the Sandia 17-m vertical axis research wind turbine (VAWT) has demonstrated the need for a systematic study of control algorithms. To this end, a computer model has been developed that uses actual wind time series and turbine performance data to calculate the power produced by the Sandia 17-m VAWT operating in automatic control. The model has been used to investigate the influence of starting algorithms on annual energy production. The results indicate that, depending on turbine and local wind characteristics, a bad choice of a control algorithm can significantly reduce overall energy production. The model can be used to select control algorithms and threshold parameters that maximize long-term energy production. An attempt has been made to generalize these results from local site and turbine characteristics to obtain general guidelines for control algorithm design.

McNerney, G.M.

1981-08-01T23:59:59.000Z

18

High Dynamic Performance Programmed PWM Control of a Multilevel Inverter with Capacitor DC Sources  

E-Print Network [OSTI]

High Dynamic Performance Programmed PWM Control of a Multilevel Inverter with Capacitor DC Sources inverter consisting of a stan- dard 3-leg inverter supplied by a DC source and three full H-bridges each reactive voltage to the motor while the standard three leg inverter can supply both reactive and active

Tolbert, Leon M.

19

Advanced Wind Turbine Controls Reduce Loads (Fact Sheet)  

SciTech Connect (OSTI)

NREL's National Wind Technology Center provides the world's only dedicated turbine controls testing platforms.

Not Available

2012-03-01T23:59:59.000Z

20

PWM Inverter control and the application thereof within electric vehicles  

DOE Patents [OSTI]

An inverter (34) which provides power to an A.C. machine (28) is controlled by a circuit (36) employing PWM control strategy whereby A.C. power is supplied to the machine at a preselectable frequency and preselectable voltage. This is accomplished by the technique of waveform notching in which the shapes of the notches are varied to determine the average energy content of the overall waveform. Through this arrangement, the operational efficiency of the A.C. machine is optimized. The control circuit includes a micro-computer and memory element which receive various parametric inputs and calculate optimized machine control data signals therefrom. The control data is asynchronously loaded into the inverter through an intermediate buffer (38). In its preferred embodiment, the present invention is incorporated within an electric vehicle (10) employing a 144 VDC battery pack (32) and a three-phase induction motor (18).

Geppert, Steven (Bloomfield Hills, MI)

1982-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "turbine controllers inverters" 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

Gas turbine bucket wall thickness control  

DOE Patents [OSTI]

A core for use in casting a turbine bucket including serpentine cooling passages is divided into two pieces including a leading edge core section and a trailing edge core section. Wall thicknesses at the leading edge and the trailing edge of the turbine bucket can be controlled independent of each other by separately positioning the leading edge core section and the trailing edge core section in the casting die. The controlled leading and trailing edge thicknesses can thus be optimized for efficient cooling, resulting in more efficient turbine operation.

Stathopoulos, Dimitrios (Glenmont, NY); Xu, Liming (Greenville, SC); Lewis, Doyle C. (Greer, SC)

2002-01-01T23:59:59.000Z

22

Aalborg Universitet Frequency Adaptive Selective Harmonic Control for Grid-Connected Inverters  

E-Print Network [OSTI]

Aalborg Universitet Frequency Adaptive Selective Harmonic Control for Grid-Connected Inverters Yang Harmonic Control for Grid-Connected Inverters. IEEE Transactions on Power Electronics, 1-13. 10.1109/TPEL Selective Harmonic Control for Grid-Connected Inverters Yongheng Yang, Student Member, IEEE, Keliang Zhou

Berning, Torsten

23

The time-delayed inverted pendulum: Implications for human balance control  

E-Print Network [OSTI]

The time-delayed inverted pendulum: Implications for human balance control John Milton,1 Juan Luis May 2009; published online 29 June 2009 The inverted pendulum is frequently used as a starting point experimental paradigms of time-delayed balance control: 1 mechanical inverted time-delayed pendulum, 2 stick

Milton, John G.

24

Control of Wind Turbines for Power Regulation and  

E-Print Network [OSTI]

Control of Wind Turbines for Power Regulation and Load Reduction Juan Jose Garcia Quirante Kongens regulation and load reduction and their ensemble in a variable-speed wind turbine. The power regulation aspects of mathematical modelling of wind turbines, and especially the control methods suited for power

25

Optimizing wind turbine control system parameters  

SciTech Connect (OSTI)

The impending expiration of the levelized period in the Interim Standard Offer Number 4 (ISO4) utility contracts for purchasing wind-generated power in California mandates, more than ever, that windplants be operated in a cost-effective manner. Operating plans and approaches are needed that maximize the net revenue from wind parks--after accounting for operation and maintenance costs. This paper describes a design tool that makes it possible to tailor a control system of a wind turbine (WT) to maximize energy production while minimizing the financial consequences of fatigue damage to key structural components. Plans for code enhancements to include expert systems and fuzzy logic are discussed, and typical results are presented in which the code is applied to study the controls of a generic Danish 15-m horizontal axis wind turbine (HAWT).

Schluter, L.L. [Sandia National Labs., Albuquerque, NM (United States); Vachon, W.A. [Vachon (W.A.) and Associates, Inc., Manchester, MA (United States)

1993-08-01T23:59:59.000Z

26

Dynamic performance and control of a static var generator using cascade multilevel inverters  

SciTech Connect (OSTI)

A cascade multilevel inverter is proposed for static VAR shifting, compensation/generation applications. The new cascade M-level inverter consists of (M-1)/2 single-phase full bridges in which each bridge has its own separate dc source. This inverter can generate almost sinusoidal waveform voltage with only one time switching per cycle. It can eliminate the need for transformers in multipulse inverters. A prototype static VAR generator (SVG) system using 11- level cascade inverter (21-level line-to-line voltage waveform) has been built. The output voltage waveform is equivalent to that of a 60- pulse inverter. This paper focuses on dynamic performance of the cascade inverter based SVG system. Control schemes are proposed to achieve a fast response which is impossible for a conventional static VAR compensator (SVC). Analytical, simulated and experimental results show the superiority of the proposed SVG system.

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

1996-10-01T23:59:59.000Z

27

Pitch-controlled variable-speed wind turbine generation  

SciTech Connect (OSTI)

Wind energy is a viable option to complement other types of pollution-free generation. In the early development of wind energy, the majority of wind turbines were operated at constant speed. Recently, the number of variable-speed wind turbines installed in wind farms has increased and more wind turbine manufacturers are making variable-speed wind turbines. This paper covers the operation of variable-speed wind turbines with pitch control. The system the authors considered is controlled to generate maximum energy while minimizing loads. The maximization of energy was only carried out on a static basis and only drive train loads were considered as a constraint. In medium wind speeds, the generator and power converter control the wind turbine to capture maximum energy from the wind. In the high wind speed region, the wind turbine is controlled to maintain the aerodynamic power produced by the wind turbine. Two methods to adjust the aerodynamic power were investigated: pitch control and generator load control, both of which are employed to control the operation of the wind turbine. The analysis and simulation shows that the wind turbine can be operated at its optimum energy capture while minimizing the load on the wind turbine for a wide range of wind speeds.

Muljadi, E.; Butterfield, C.P.

2000-03-01T23:59:59.000Z

28

IMPLEMENTATION OF WIND TURBINE CONTROLLERS W.E.Leithead  

E-Print Network [OSTI]

IMPLEMENTATION OF WIND TURBINE CONTROLLERS D.J.Leith W.E.Leithead Department of Electronic-speed wind turbines are considered, namely, (1) accommodation of the strongly nonlinear rotor aerodynamics derived and extended to cater for all wind turbine configurations. A rigorous stability analysis

Duffy, Ken

29

Disturbance Control of the Hydraulic Brake in a Wind Turbine  

E-Print Network [OSTI]

Disturbance Control of the Hydraulic Brake in a Wind Turbine Frank Jepsen, Anders Søborg brake in a wind turbine. Brake torque is determined by friction coefficient and clamp force; the latter brake is one1 of the two independent brake systems in a wind turbine. As a consequence of the gearing

Yang, Zhenyu

30

PWM Inverter-Fed Induction Motor-Based Electrical Vehicles Fault-Tolerant Control  

E-Print Network [OSTI]

PWM Inverter-Fed Induction Motor-Based Electrical Vehicles Fault-Tolerant Control Bekhera Tabbache proposes a fault-tolerant control scheme for PWM inverter-fed induction motor-based electric vehicles and simulations on an electric vehicle are carried-out using a European urban driving cycle to assess the FTC

Paris-Sud XI, Universit de

31

A Preliminary Cost Study of the Dual Mode Inverter Controller  

SciTech Connect (OSTI)

In 1998, the Power Electronics and Electric Machinery Research Center (PEEMRC) at the Oak Ridge National Laboratory (ORNL) started a program to investigate alternate field weakening schemes for permanent magnet (PM) motors. The adjective ''alternate'' was used because at that time, outside research emphasis was on motors with interior-mounted PMs (IPMs). The PEEMRC emphasis was placed on motors with surface-mounted PMs (SPMs) because of the relative ease of manufacturing SPM motors compared with the IPM motors. Today the PEEMRC is continuing research on SPMs while examining the IPMs that have been developed by industry. Out of this task--the goal of which was to find ways to drive PM motors that inherently have low inductance at high speeds where their back-emf exceeds the supply voltage--ORNL developed and demonstrated the dual mode inverter control (DMIC) [1,2] method of field weakening for SPM motors. The predecessor of DMIC is conventional phase advance (CPA), which was developed by UQM Technologies, Inc. [3]. Fig. 1 shows the three sets of anti-parallel thyristors in the dashed box that comprise the DMIC. If one removes the dashed box by shorting each set of anti-parallel thyristors, the configuration becomes a conventional full bridge inverter on the left driving a three phase motor on the right. CPA may be used to drive this configuration ORNL's initial analyses of CPA and DMIC were based on driving motors with trapezoidal back-emfs [4-6], obtained using double layer lapped stator windings with one slot per pole per phase. A PM motor with a sinusoidal back-emf obtained with two poles per slot per phase has been analyzed under DMIC operation as a University of Tennessee-Knoxville (UTK) doctoral dissertation [7]. In the process of this research, ORNL has completed an analysis that explains and quantifies the role of inductance in these methods of control. The Appendix includes information on the equations for the three components of phase inductance, L{sub gap}, L{sub slot}, and L{sub endturns}. PM motors inherently have a lower inductance because of the increase in effective air gap caused by the magnet, which is in the denominator of the equation for L{sub gap}. L{sub gap} accounts for about half of the phase inductance. Because of the low inductance, there is a propensity for currents to exceed the motor's rated value. DMIC solves this problem for low-inductance PM motors and, in addition, provides a number of safety features that protect against uncontrolled generator mode operation [8,9]; however, the DMIC topology adds a pair of anti-parallel thyristors in each of the three phases, thereby introducing additional silicon costs as well as additional voltage drops during operation. It poses the tradeoff question; under what conditions can the beneficial features of DMIC offset its additional silicon cost and voltage drop losses? The purpose of this report is to address the tradeoff question. Sections of the report will: (1) review the role of self-inductance in performance and control of PM motors, (2) discuss the bounding inductances for motors with trapezoidal back-emfs under CPA control, (3) discuss the bounding inductances for trapezoidal back-emfs under DMIC, (4) discuss the bounding inductances for the PM synchronous motor (PMSM), (5) present the analysis showing how DMIC minimizes current in PMSMs, (6) present the results of a cost study conducted for two motors driven using a CPA inverter and for two motors driven using DMIC, (7) discuss estimating life cycle cost benefits, and (8) present conclusions.

McKeever, J.W.

2005-01-28T23:59:59.000Z

32

NREL: News - NREL Study: Active Power Control of Wind Turbines...  

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

414 NREL Study: Active Power Control of Wind Turbines Can Improve Power Grid Reliability January 20, 2014 The Energy Department's National Renewable Energy Laboratory (NREL), along...

33

Controller Field Tests on the NREL CART2 Turbine  

SciTech Connect (OSTI)

This document presents the results of the field tests carried out on the CART2 turbine at NREL to validate individual pitch control and active tower damping.

Bossanyi, E.; Wright, A.; Fleming, P.

2010-12-01T23:59:59.000Z

34

Optimal Inverter VAR Control in Distribution Systems with High PV Penetration  

E-Print Network [OSTI]

and the net benefits, taking into account the additional cost of inverter losses when operating at non systems. Solar energy is highly intermittent and this introduces several challenges to existing utility is to demonstrate the benefits of inverter var control on a fast timescale to mitigate rapid and large voltage

Low, Steven H.

35

IEEE TRANSACTIONS ON POWER ELECTRONICS 1 A Hybrid Power Control Concept for PV Inverters with Reduced  

E-Print Network [OSTI]

- cept for grid-connected Photovoltaic (PV) inverters. The control strategy is based on either a Maximum concept. Index Terms--Photovoltaic inverters, constant power genera- tion, maximum power point tracking, efficiency, thermal loading, reliability. I. INTRODUCTION MAXIMUM Power Point Tracking (MPPT) is effective

Kerekes, Tamas

36

Wind Turbine Pitch Angle Controllers for Grid Frequency Stabilisation  

E-Print Network [OSTI]

Wind Turbine Pitch Angle Controllers for Grid Frequency Stabilisation Clemens Jauch Risø National Laboratory Wind Energy Department P.O. Box 49 DK-4000 Roskilde, Denmark clemens.jauch@risoe.dk Abstract: In this paper it is investigated how active-stall wind turbines can contribute to the stabilisation of the power

37

Advanced Control Design for Wind Turbines; Part I: Control Design, Implementation, and Initial Tests  

SciTech Connect (OSTI)

The purpose of this report is to give wind turbine engineers information and examples of the design, testing through simulation, field implementation, and field testing of advanced wind turbine controls.

Wright, A. D.; Fingersh, L. J.

2008-03-01T23:59:59.000Z

38

Direct power control of grid connected PV systems with three level NPC inverter  

SciTech Connect (OSTI)

This paper presents the control of a three-level Neutral Point Clamped (NPC) voltage source inverter for grid connected photovoltaic (PV) systems. The control method used is the Extended Direct Power Control (EDPC), which is a generic approach for Direct Power Control (DPC) of multilevel inverters based on geometrical considerations. Maximum Power Point Tracking (MPPT) algorithms, that allow maximal power conversion into the grid, have been included. These methods are capable of extracting maximum power from each of the independent PV arrays connected to each DC link voltage level. The first one is a conventional MPPT which outputs DC link voltage references to EDPC. The second one is based on DPC concept. This new MPPT outputs power increment references to EDPC, thus avoiding the use of a DC link voltage regulator. The whole control system has been tested on a three-level NPC voltage source inverter connected to the grid and results confirm the validity of the method. (author)

Alonso-Martinez, Jaime; Eloy-Garcia, Joaquin; Arnaltes, Santiago [Dept. of Electrical Engineering, University Carlos III of Madrid, Avda. Universidad 30, 28911 Leganes, Madrid (Spain)

2010-07-15T23:59:59.000Z

39

Wind Turbine Blade Flow Fields and Prospects for Active Aerodynamic Control: Preprint  

SciTech Connect (OSTI)

This paper describes wind turbine flow fields that can cause adverse aerodynamic loading and can impact active aerodynamic control methodologies currently contemplated for wind turbine applications.

Schreck, S.; Robinson, M.

2007-08-01T23:59:59.000Z

40

Inverted-UShaped Dopamine Actions on Human Working Memory and Cognitive Control  

E-Print Network [OSTI]

Cools and Mark D'Esposito Brain dopamine (DA) has long been implicated in cognitive control processesREVIEW Inverted-U­Shaped Dopamine Actions on Human Working Memory and Cognitive Control Roshan, cognitive control is a multifactorial phenomenon, requiring a dynamic balance between cognitive stability

Note: This page contains sample records for the topic "turbine controllers inverters" 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

Turbines  

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

CO2 Power Cycles Advanced Combustion Turbines Advanced Research University Turbine Systems Research SBIR Program Plan Project Portfolio Project Information Publications...

42

Turbine airfoil with controlled area cooling arrangement  

DOE Patents [OSTI]

A gas turbine airfoil (10) includes a serpentine cooling path (32) with a plurality of channels (34,42,44) fluidly interconnected by a plurality of turns (38,40) for cooling the airfoil wall material. A splitter component (50) is positioned within at least one of the channels to bifurcate the channel into a pressure-side channel (46) passing in between the outer wall (28) and the inner wall (30) of the pressure side (24) and a suction-side channel (48) passing in between the outer wall (28) and the inner wall (30) of the suction side (26) longitudinally downstream of an intermediate height (52). The cross-sectional area of the pressure-side channel (46) and suction-side channel (48) are thereby controlled in spite of an increasing cross-sectional area of the airfoil along its longitudinal length, ensuring a sufficiently high mach number to provide a desired degree of cooling throughout the entire length of the airfoil.

Liang, George

2010-04-27T23:59:59.000Z

43

Advanced controls for floating wind turbines  

E-Print Network [OSTI]

Floating Offshore Wind Turbines (FOWT) is a technology that stands to spearhead the rapid growth of the offshore wind energy sector and allow the exploration of vast high quality wind resources over coastal and offshore ...

Casanovas, Carlos (Casanovas Bermejo)

2014-01-01T23:59:59.000Z

44

A High-Order Sliding Mode Observer for Sensorless Control ofDFIG-Based Wind Turbines  

E-Print Network [OSTI]

A High-Order Sliding Mode Observer for Sensorless Control ofDFIG-Based Wind Turbines Mohamed control of a doubly-fed induction generator (DFIG) based wind turbine. The sensorless control scheme (generator and turbine). Simulations using the wind turbine simulator FAST on a 1.5- MW three-blade wind

Boyer, Edmond

45

MODELING AND CONTROL OF A O2/CO2 GAS TURBINE CYCLE FOR CO2 CAPTURE  

E-Print Network [OSTI]

MODELING AND CONTROL OF A O2/CO2 GAS TURBINE CYCLE FOR CO2 CAPTURE Lars Imsland Dagfinn Snarheim and control of a semi-closed O2/CO2 gas turbine cycle for CO2 capture. In the first part the process predictive control, Gas turbines, CO2 capture 1. INTRODUCTION Gas turbines are widely used for power

Foss, Bjarne A.

46

770 IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS, VOL. 42, NO. 3, MAY/JUNE 2006 Constant Boost Control of the Z-Source Inverter to  

E-Print Network [OSTI]

Control of the Z-Source Inverter to Minimize Current Ripple and Voltage Stress Miaosen Shen, Student-control methods for the Z-source inverter, which can obtain maximum voltage gain at any given modulation index--Pulsewidth modulation (PWM), voltage boost, Z-source inverter. I. INTRODUCTION IN A traditional voltage-source inverter

Tolbert, Leon M.

47

Control of Inverter-Connected Sources in Autonomous Microgrids Ian A. Hiskens Eric M. Fleming  

E-Print Network [OSTI]

Control of Inverter-Connected Sources in Autonomous Microgrids Ian A. Hiskens Eric M. Fleming interconnection strate- gies. The resulting microgrid concept allows sub-networks of sources and loads to maintain to a microgrid, explores controller behaviour. The investigation considers disconnection from the main grid

Hiskens, Ian A.

48

Independent Control of Two Induction Motors Fed by a Five Legs PWM Inverter for Electric Vehicles  

E-Print Network [OSTI]

Independent Control of Two Induction Motors Fed by a Five Legs PWM Inverter for Electric Vehicles B. NOMENCLATURE EV = Electric vehicle; IM = Induction motor; IFOC = Indirect field oriented control; PWM= Pulse force; Fcr = Climbing and downgrade resistance force; Pv = Vehicle driving power; J = Total inertia

Boyer, Edmond

49

Design, Analysis, and Learning Control of a Fully Actuated Micro Wind Turbine  

E-Print Network [OSTI]

Design, Analysis, and Learning Control of a Fully Actuated Micro Wind Turbine J. Zico Kolter of renewable energy, and improvements to wind turbine design and control can have a significant impact a actuated micro wind turbine intended for research purposes. While most academic work on wind turbine

Tedrake, Russ

50

Designing and Testing Controls to Mitigate Tower Dynamic Loads in the Controls Advanced Research Turbine: Preprint  

SciTech Connect (OSTI)

This report describes NREL's efforts to design, implement, and test advanced controls for maximizing energy extraction and reducing structural dynamic loads in wind turbines.

Wright, A. D.; Fingersh, L. J.; Stol, K. A.

2007-01-01T23:59:59.000Z

51

Testing State-Space Controls for the Controls Advanced Research Turbine: Preprint  

SciTech Connect (OSTI)

Control can improve wind turbine performance by enhancing energy capture and reducing dynamic loads. At the National Renewable Energy Laboratory, we are implementing and testing state-space controls on the Controls Advanced Research Turbine (CART), a turbine specifically configured to test advanced controls. We show the design of control systems to regulate turbine speed in Region 3 using rotor collective pitch and reduce dynamic loads in Regions 2 and 3 using generator torque. These controls enhance damping in the first drive train torsion mode. We base these designs on sensors typically used in commercial turbines. We evaluate the performance of these controls by showing field test results. We also compare results from these modern controllers to results from a baseline proportional integral controller for the CART. Finally, we report conclusions to this work and outline future studies.

Wright, A. D.; Fingersh, L. J.; Balas, M. J.

2006-01-01T23:59:59.000Z

52

IEEE POWER ELECTRONICS LETTERS, VOL. 2, NO. 2, JUNE 2004 51 Digital Phase Control for Resonant Inverters  

E-Print Network [OSTI]

. In this letter, we present and verify a new concept for direct digital phase control of resonant invertersIEEE POWER ELECTRONICS LETTERS, VOL. 2, NO. 2, JUNE 2004 51 Digital Phase Control for Resonant Inverters Yan Yin, Student Member, IEEE, and Regan Zane, Member, IEEE Abstract--This letter presents

53

Power control of a wind farm with active stall wind turbines and AC grid connection  

E-Print Network [OSTI]

Power control of a wind farm with active stall wind turbines and AC grid connection Anca D. Hansen1 controller for a wind farm made-up exclusively of active stall wind turbines with AC grid connection wind farm control involves both the control on wind turbine level as well as the central control

54

Cost analysis of NOx control alternatives for stationary gas turbines  

SciTech Connect (OSTI)

The use of stationary gas turbines for power generation has been growing rapidly with continuing trends predicted well into the future. Factors that are contributing to this growth include advances in turbine technology, operating and siting flexibility and low capital cost. Restructuring of the electric utility industry will provide new opportunities for on-site generation. In a competitive market, it maybe more cost effective to install small distributed generation units (like gas turbines) within the grid rather than constructing large power plants in remote locations with extensive transmission and distribution systems. For the customer, on-site generation will provide added reliability and leverage over the cost of purchased power One of the key issues that is addressed in virtually every gas turbine application is emissions, particularly NO{sub x} emissions. Decades of research and development have significantly reduced the NO{sub x} levels emitted from gas turbines from uncontrolled levels. Emission control technologies are continuing to evolve with older technologies being gradually phased-out while new technologies are being developed and commercialized. The objective of this study is to determine and compare the cost of NO{sub x} control technologies for three size ranges of stationary gas turbines: 5 MW, 25 MW and 150 MW. The purpose of the comparison is to evaluate the cost effectiveness and impact of each control technology as a function of turbine size. The NO{sub x} control technologies evaluated in this study include: Lean premix combustion, also known as dry low NO{sub x} (DLN) combustion; Catalytic combustion; Water/steam injection; Selective catalytic reduction (SCR)--low temperature, conventional, high temperature; and SCONO{sub x}{trademark}.

Bill Major

1999-11-05T23:59:59.000Z

55

A 7-Level Single DC Source Cascaded H-Bridge Multilevel Inverters Control  

E-Print Network [OSTI]

vehicles or hybrid electric vehicles where each phase of the inverter can be implemented using only HE electric vehicles (EV) and Hybrid Electric Vehicles (HEV) currently seem to constitute, the motor drive, comprising the electric motor, the power converter, and the electronic controller

Paris-Sud XI, Université de

56

Extended Constant Power Speed Range of the Brushless DC Motor Through Dual Mode Inverter Control  

SciTech Connect (OSTI)

The trapezoidal back electromotive force (emf) brushless direct current (dc) motor (BDCM) with surface-mounted magnets has high-power density and efficiency especially when rare-earth magnet materials are used. Traction applications, such as electric vehicles, could benefit significantly from the use of such motors. Unfortunately, a practical means for driving the motor over a constant power speed ratio (CPSR) of 5:1 or more has not yet been developed. A key feature of these motors is that they have low internal inductance. The phase advance method is effective in controlling the motor power over such a speed range, but the current at high speed may be several times greater than that required at the base speed. The increase in current during high-speed operation is due to the low motor inductance and the action of the bypass diodes of the inverter. The use of such a control would require increased current rating of the inverter semiconductors and additional cooling for the inverter, where the conduction losses increase proportionally with current, and especially for the motor, where the losses increase with the square of the current. The high current problems of phase advance can be mitigated by adding series inductance; however, this reduces power density, requires significant increase in supply voltage, and leaves the CPSR performance of the system highly sensitive to variations in the available voltage. A new inverter topology and control scheme has been developed that can drive low-inductance BDCMs over the CPSR that would be required in electric vehicle applications. This new controller is called the dual-mode inverter control (DMIC). It is shown that the BDCM has an infinite CPSR when it is driven by the DMIC.

Lawler, J.S.

2000-06-23T23:59:59.000Z

57

Dynamic control of wind turbines Andrew Kusiak*, Wenyan Li, Zhe Song  

E-Print Network [OSTI]

Dynamic control of wind turbines Andrew Kusiak*, Wenyan Li, Zhe Song Department of Mechanical Keywords: Wind turbine Wind energy Data mining Model predictive control Evolutionary computation algorithm Control strategy optimization a b s t r a c t The paper presents an intelligent wind turbine control

Kusiak, Andrew

58

LQG control of horizontal wind turbines for blades and tower loads alleviation  

E-Print Network [OSTI]

LQG control of horizontal wind turbines for blades and tower loads alleviation A. Pintea*, N of power produced by two bladed horizontal variable speed wind turbines. The proposed controller ensures oscillations and with the tower bending tendency. Keywords: LQG control, Wind turbines, Multi-objective control

Paris-Sud XI, Université de

59

Active NOX Control of Cogen Gas Turbine Exhaust using a Nonlinear Feed Forward with Cascade Architecture  

E-Print Network [OSTI]

Active NOX Control of Cogen Gas Turbine Exhaust using a Nonlinear Feed Forward with Cascade control, cogeneration, gas turbine, model based control, feed forward, cascade ABSTRACT Presented is a model based strategy for controlling the NOX concentration of natural gas turbine emissions

Cooper, Doug

60

Tutorial of Wind Turbine Control for Supporting Grid Frequency through Active Power Control: Preprint  

SciTech Connect (OSTI)

As wind energy becomes a larger portion of the world's energy portfolio and wind turbines become larger and more expensive, wind turbine control systems play an ever more prominent role in the design and deployment of wind turbines. The goals of traditional wind turbine control systems are maximizing energy production while protecting the wind turbine components. As more wind generation is installed there is an increasing interest in wind turbines actively controlling their power output in order to meet power setpoints and to participate in frequency regulation for the utility grid. This capability will be beneficial for grid operators, as it seems possible that wind turbines can be more effective at providing some of these services than traditional power plants. Furthermore, establishing an ancillary market for such regulation can be beneficial for wind plant owner/operators and manufacturers that provide such services. In this tutorial paper we provide an overview of basic wind turbine control systems and highlight recent industry trends and research in wind turbine control systems for grid integration and frequency stability.

Aho, J.; Buckspan, A.; Laks, J.; Fleming, P.; Jeong, Y.; Dunne, F.; Churchfield, M.; Pao, L.; Johnson, K.

2012-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "turbine controllers inverters" 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

Real-Time Wind Turbine Emulator Suitable for Power Quality and Dynamic Control Studies  

E-Print Network [OSTI]

1 Real-Time Wind Turbine Emulator Suitable for Power Quality and Dynamic Control Studies Dale S. L. Dolan, Student Member, IEEE, P. W. Lehn, Member IEEE Abstract-- Wind turbines are increasingly becoming-time Wind Turbine Emulator, which emulates the dynamic torque produced by an actual turbine has been

Lehn, Peter W.

62

Energy Based Methods in Wind Turbine Control CeSOS Highlights and AMOS Visions  

E-Print Network [OSTI]

Energy Based Methods in Wind Turbine Control CeSOS Highlights and AMOS Visions Morten D. Pedersen 1 / 26 #12;This talk 1 Background 2 Understanding the Wind Turbine 3 Nonlinear Turbine Modeling 4;Background The Problem Previously stable wind turbine systems began exhibiting resonant behavior when put

Nørvåg, Kjetil

63

Analysis, control and applications of neutral point clamped PWM inverters  

E-Print Network [OSTI]

) and MOSFET transistor devices. Also the advancements in high voltage integrated circuit (HVIC) technology have demonstrated the integration of power devices and their control logic thereby promising simplified implementation of future power processing... power supplies, the pulse width nrodulation (PWM) method of power control has emerged as a viable means of' power control, providing the facility to adjust the output voltage and frequency with sinmltaneous attenuation of several lower order...

Jakkli, Ranjit V

1991-01-01T23:59:59.000Z

64

Developing inverted pendulum as a teaching tool for controller designs  

E-Print Network [OSTI]

) Controller design Robustness Analysis Designed Contmllers Simulation (Simulink) Fine tune User Interface (Monitor) Satisfactory Contml Loop (PC) Implementation Special Hardware Real-Time Opemtion Real Plant Fig. 4. Components and basic... FOR CONVENIENT IMPLEMENTATION . 5. 1. Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . 5. 2. User Interface Design 5. 3. Control Loop Design 5. 3, 1. Real-Time Implementation. 5. 3. 2. Data Acquisition 5. 3. 3. Examples of Control...

Lin, Han-Ming

1994-01-01T23:59:59.000Z

65

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

66

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

E-Print Network [OSTI]

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

Silva, Filipe Faria Da

67

WindTurbineGenerator Introduction of the Renewable Micro-Grid Test-Bed  

E-Print Network [OSTI]

Simulator Wind Turbine: PMSM, 3kW, 8.3A Wind Generator: PMSM, 3kW, 8.3A 3 AC/DC Converter & DC/AC Inverter Wind Turbine: Torque or Speed Control Wind Generator: PQ Control Cubicle #4: Energy Storage Generator #1 3kW, 8.3A Wind Turbine #1 3kW, 8.3A Wind Turbine #2 3kW Wind Generator #2 3kW RS232

Johnson, Eric E.

68

High-Order Sliding Mode Control for DFIG-Based Wind Turbine Fault Ride-Through  

E-Print Network [OSTI]

High-Order Sliding Mode Control for DFIG-Based Wind Turbine Fault Ride-Through Mohamed Benbouzid Turbine (WT) using High-Order Sliding Mode (HOSM) control. Indeed, it has been recently suggested wind turbine are carried-out to evaluate ride-through performance of the proposed HOSM control strategy

Paris-Sud XI, Université de

69

Fault-tolerant model predictive control of a wind turbine benchmark  

E-Print Network [OSTI]

Fault-tolerant model predictive control of a wind turbine benchmark X. Yang J.M. Maciejowski tolerant control problem of a wind turbine benchmark. A hierarchical controller with model predictive pre component of the wind turbine. The global MPC is used to schedule the operation of the components

Cambridge, University of

70

Aeroderivative Gas Turbines Can Meet Stringent NOx Control Requirements  

E-Print Network [OSTI]

for controlling NOx emissions will be discussed. Steam injection has a very favorable effect on engine performance raising both the power output and efficiency. As an example, full steam injection in the GE LM5000 gas turbine :tncreases the power output from... methods for reducing the NOx levels of the LM2500 and LM5000 engines. These engines are aircraft-derivative turbine engines, which are used in a variety of industrial applications. Efforts have been concentrated on the use of water or steam injection...

Keller, S. C.; Studniarz, J. J.

71

Phase Locked Loop Control of Inverters in a Microgrid  

E-Print Network [OSTI]

cells, wind power, microturbines, and batteries. Synchronous sources, such as diesel gensets-scale electricity supply net- works that have local power generation. This paper considers a control strategy that goal, the proposed con- troller uses droop characteristics for active-power/frequency and reactive-power

Hiskens, Ian A.

72

Removable inner turbine shell with bucket tip clearance control  

DOE Patents [OSTI]

A turbine includes a plurality of inner shell sections mounting first and second stage nozzle and shroud portions. The inner shell sections are pinned to an outer containment shell formed of sections to preclude circumferential movement of the inner shell relative to the outer shell and enable thermal expansion and contraction of the inner shell relative to the outer shell. Positive bucket tip clearance control is afforded by passing a thermal medium about the inner shell in heat transfer relation with the shrouds about the first and second stage bucket tips, the thermal medium being provided from a source of heating/cooling fluid independent of the turbine. Access is provided to the rotor and turbine buckets by removing the outer and inner shell sections.

Sexton, Brendan F. (Clifton Park, NY); Knuijt, Hans M. (Niskayuna, NY); Eldrid, Sacheverel Q. (Saratoga Springs, NY); Myers, Albert (Amsterdam, NY); Coneybeer, Kyle E. (Schenectady, NY); Johnson, David Martin (Ballston Lake, NY); Kellock, Iain R. (Clifton Park, NY)

2000-01-01T23:59:59.000Z

73

Modular Inverter for Advanced Control Applications In the fall of 2003, a team of graduate students was assembled to design and construct a  

E-Print Network [OSTI]

a set of well-documented inverters of various ratings capable of quickly implementing a new control-powernts2\\ece power design archives\\documents\\specification documents\\sd00004-001 modular inverter systemModular Inverter for Advanced Control Applications May 2006 In the fall of 2003, a team of graduate

Kimball, Jonathan W.

74

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

SciTech Connect (OSTI)

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

75

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

E-Print Network [OSTI]

Individual Pitch Control for Mitigation of Power Fluctuation of Variable Speed Wind Turbines, China mcheng@seu.edu.cn Abstract-- Grid connected wind turbines are the sources of power fluctuations presents an individual pitch control (IPC) strategy to mitigate the wind turbine power fluctuation at both

Hu, Weihao

76

Second-Order Sliding Mode Control for DFIG-Based Wind Turbines  

E-Print Network [OSTI]

Second-Order Sliding Mode Control for DFIG-Based Wind Turbines Fault Ride-Through Capability-based wind turbine using a high-order sliding mode control. Indeed, it has been recently suggested extra mechanical stress on the wind turbine drive train). Simulations using the NREL FAST code on a 1

Brest, Université de

77

CONTROL ISSUES IN THE DESIGN OF A GAS TURBINE CYCLE FOR CO2 CAPTURE  

E-Print Network [OSTI]

CONTROL ISSUES IN THE DESIGN OF A GAS TURBINE CYCLE FOR CO2 CAPTURE Query Sheet Q1: AU: short title OF A GAS TURBINE CYCLE FOR CO2 CAPTURE Lars Imsland, Dagfinn Snarheim, and Bjarne A. Foss Department-closed / gas turbine cycle for capture. Some control strategies and their interaction with the process design

Foss, Bjarne A.

78

High-Order Sliding Mode Control of DFIG-Based Marine Current Turbine  

E-Print Network [OSTI]

High-Order Sliding Mode Control of DFIG-Based Marine Current Turbine S.E. Ben Elghali1 , M-based marine current turbine. Indeed, to increase the generated power and therefore the efficiency of a marine current turbine, a nonlinear controller has been proposed. DFIG has been already considered for similar

Brest, Université de

79

Gain-scheduled `1 -optimal control for boiler-turbine dynamics  

E-Print Network [OSTI]

, into the mechanical energy acting on the turbine and generator. The steam generated in the boiler system servesGain-scheduled `1 -optimal control for boiler-turbine dynamics with actuator saturation Pang; accepted 2 June 2003 Abstract This paper presents a gain-scheduled approach for boiler-turbine controller

Shamma, Jeff S.

80

Nonlinear Model Predictive Control of an Aircraft Gas Turbine Engine Brent. J. Brunell  

E-Print Network [OSTI]

Nonlinear Model Predictive Control of an Aircraft Gas Turbine Engine Brent. J. Brunell , Robert R the potential to achieve better performance than the production controller. 1 Introduction Gas turbines can turbine model considered is a low bypass, two rotor, turbojet with a variable exhaust area typical

Bitmead, Bob

Note: This page contains sample records for the topic "turbine controllers inverters" 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

Systematic Controller Design Methodology for Variable-Speed Wind Turbines  

SciTech Connect (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

82

Field Testing LIDAR Based Feed-Forward Controls on the NREL Controls Advanced Research Turbine: Preprint  

SciTech Connect (OSTI)

Wind turbines are complex, nonlinear, dynamic systems driven by aerodynamic, gravitational, centrifugal, and gyroscopic forces. The aerodynamics of wind turbines are nonlinear, unsteady, and complex. Turbine rotors are subjected to a chaotic three-dimensional (3-D) turbulent wind inflow field with imbedded coherent vortices that drive fatigue loads and reduce lifetime. In order to reduce cost of energy, future large multimegawatt turbines must be designed with lighter weight structures, using active controls to mitigate fatigue loads, maximize energy capture, and add active damping to maintain stability for these dynamically active structures operating in a complex environment. Researchers at the National Renewable Energy Laboratory (NREL) and University of Stuttgart are designing, implementing, and testing advanced feed-back and feed-forward controls in order to reduce the cost of energy for wind turbines.

Scholbrock, A. K.; Fleming, P. A.; Fingersh, L. J.; Wright, A. D.; Schlipf, D.; Haizmann, F.; Belen, F.

2013-01-01T23:59:59.000Z

83

Influence of Control on the Pitch Damping of a Floating Wind Turbine  

SciTech Connect (OSTI)

This paper presents the influence of conventional wind turbine blade-pitch control actions on the pitch damping of a wind turbine supported by an offshore floating barge with catenary moorings.

Jonkman, J. M.

2008-03-01T23:59:59.000Z

84

Plasma Aerodynamic Control Effectors for Improved Wind Turbine Performance  

SciTech Connect (OSTI)

Orbital Research Inc is developing an innovative Plasma Aerodynamic Control Effectors (PACE) technology for improved performance of wind turbines. The PACE system is aimed towards the design of "smart" rotor blades to enhance energy capture and reduce aerodynamic loading and noise using flow-control. The PACE system will provide ability to change aerodynamic loads and pitch distribution across the wind turbine blade without any moving surfaces. Additional benefits of the PACE system include reduced blade structure weight and complexity that should translate into a substantially reduced initial cost. During the Phase I program, the ORI-UND Team demonstrated (proof-of-concept) performance improvements on select rotor blade designs using PACE concepts. Control of both 2-D and 3-D flows were demonstrated. An analytical study was conducted to estimate control requirements for the PACE system to maintain control during wind gusts. Finally, independent laboratory experiments were conducted to identify promising dielectric materials for the plasma actuator, and to examine environmental effects (water and dust) on the plasma actuator operation. The proposed PACE system will be capable of capturing additional energy, and reducing aerodynamic loading and noise on wind turbines. Supplementary benefits from the PACE system include reduced blade structure weight and complexity that translates into reduced initial capital costs.

Mehul P. Patel; Srikanth Vasudevan; Robert C. Nelson; Thomas C. Corke

2008-08-01T23:59:59.000Z

85

Development of a Control and Monitoring Platform Based on Fuzzy Logic for Wind Turbine Gearboxes .  

E-Print Network [OSTI]

??It is preferable that control and bearing condition monitoring are integrated, as the condition of the system should influence control actions. As wind turbines mainly (more)

Chen, Wei

2012-01-01T23:59:59.000Z

86

Analysis and control of a nonlinear boiler-turbine unit Wen Tan a,*,1  

E-Print Network [OSTI]

Analysis and control of a nonlinear boiler-turbine unit Wen Tan a,*,1 , Horacio J. Marquez b, and the concept is applied to a boiler-turbine unit to analyze its dynamics. It is shown that the unit shows. Keywords: Boiler-turbine unit; Nonlinearity measure; Gap metric; Anti-windup bumpless transfer techniques

Marquez, Horacio J.

87

Mitigation of Fatigue Loads Using Individual Pitch Control of Wind Turbines Based on FAST  

E-Print Network [OSTI]

Mitigation of Fatigue Loads Using Individual Pitch Control of Wind Turbines Based on FAST Yunqian University, China jiz@seu.edu.cn Abstract-With the increase of wind turbine dimension and capacity, the wind turbine structures are subjected to prominent loads and fatigue which would reduce the lifetime of wind

Chen, Zhe

88

A Robust STATCOM Control to Augment LVRT capability of Fixed Speed Wind Turbines  

E-Print Network [OSTI]

A Robust STATCOM Control to Augment LVRT capability of Fixed Speed Wind Turbines M. J. Hossain, H Compensator (STATCOM) to enhance the Low-Voltage Ride- Through (LVRT) capability of fixed-speed wind turbines cost and maintenance due to rugged brushless construction. Constant speed wind turbines equipped

Pota, Himanshu Roy

89

Modelling and control of wind turbines A. Pintea 1,2  

E-Print Network [OSTI]

Modelling and control of wind turbines A. Pintea 1,2 , D. Popescu 1 , P. Borne 2 1 University an important challenge. From all types of renewable energy sources, wind turbines proved to be one starts with a state of the art of wind turbines and their problematic and continues with the presentation

Boyer, Edmond

90

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

E-Print Network [OSTI]

EFFECT OF PITCH CONTROL AND POWER CONDITIONING ON POWER QUALITY OF VARIABLE SPEED WIND TURBINE), Curtin University of Technology, WA Abstract: Variable speed wind turbine generators provide the opportunity to capture more power than fixed speed turbines. However the variable speed machine output can

91

High-Order Sliding Mode Control of a Marine Current Turbine  

E-Print Network [OSTI]

High-Order Sliding Mode Control of a Marine Current Turbine Driven Permanent Magnet Synchronous of a Permanent Magnet Synchronous Generator (PMSG)-based Marine Current Turbine (MCT). Indeed, to increase been already considered for similar applications particularly wind turbine systems using mainly PI

Paris-Sud XI, Université de

92

DFIG Driven Wind Turbine Grid Fault-Tolerance Using High-Order Sliding Mode Control  

E-Print Network [OSTI]

DFIG Driven Wind Turbine Grid Fault-Tolerance Using High-Order Sliding Mode Control Mohamed fault-tolerance of a doubly-fed induction generator- based wind turbine using high-order sliding mode mechanical stress on the drive train). Simulations using the NREL FAST code on a 1.5-MW wind turbine

Boyer, Edmond

93

High-Order Sliding Mode Control of a DFIG-Based Wind Turbine  

E-Print Network [OSTI]

High-Order Sliding Mode Control of a DFIG-Based Wind Turbine for Power Maximization and Grid Fault tolerance of a Doubly-Fed Induction Generator (DFIG)-based Wind Turbine (WT). These variable speed systems have several advantages over the traditional wind turbine operating methods, such as the reduction

Paris-Sud XI, Université de

94

ACTIVE CONTROL OF FLOW SEPARATION AND STRUCTURAL VIBRATIONS OF WIND TURBINE BLADES  

E-Print Network [OSTI]

ACTIVE CONTROL OF FLOW SEPARATION AND STRUCTURAL VIBRATIONS OF WIND TURBINE BLADES Sponsor: Ney actuators embedded inside the wind turbine blade to provide an efficient, rapid and compact means to alter the ability to shed excess wind loads off the blade. 3. Reduce vibration in the turbine blades by selectively

Salama, Khaled

95

CONTROL DESIGN FOR A GAS TURBINE CYCLE WITH CO2 CAPTURE CAPABILITIES  

E-Print Network [OSTI]

. The exhaust gas from a gas turbine with CO2 as working fluid, is used as heating medium for a steam cycleCONTROL DESIGN FOR A GAS TURBINE CYCLE WITH CO2 CAPTURE CAPABILITIES Dagfinn Snarheim Lars Imsland. of Science and Technology, 7491 Trondheim Abstract: The semi-closed oxy-fuel gas turbine cycle has been

Foss, Bjarne A.

96

Controlled pilot oxidizer for a gas turbine combustor  

DOE Patents [OSTI]

A combustor (22) for a gas turbine (10) includes a main burner oxidizer flow path (34) delivering a first portion (32) of an oxidizer flow (e.g., 16) to a main burner (28) of the combustor and a pilot oxidizer flow path (38) delivering a second portion (36) of the oxidizer flow to a pilot (30) of the combustor. The combustor also includes a flow controller (42) disposed in the pilot oxidizer flow path for controlling an amount of the second portion delivered to the pilot.

Laster, Walter R. (Oviedo, FL); Bandaru, Ramarao V. (Greer, SC)

2010-07-13T23:59:59.000Z

97

Combining Droop Curve Concepts with Control Systems for Wind Turbine Active Power Control: Preprint  

SciTech Connect (OSTI)

Wind energy is becoming a larger portion of the global energy portfolio and wind penetration has increased dramatically in certain regions of the world. This increasing wind penetration has driven the need for wind turbines to provide active power control (APC) services to the local utility grid, as wind turbines do not intrinsically provide frequency regulation services that are common with traditional generators. It is common for large scale wind turbines to be decoupled from the utility grid via power electronics, which allows the turbine to synthesize APC commands via control of the generator torque and blade pitch commands. Consequently, the APC services provided by a wind turbine can be more flexible than those provided by conventional generators. This paper focuses on the development and implementation of both static and dynamic droop curves to measure grid frequency and output delta power reference signals to a novel power set point tracking control system. The combined droop curve and power tracking controller is simulated and comparisons are made between simulations using various droop curve parameters and stochastic wind conditions. The tradeoffs involved with aggressive response to frequency events are analyzed. At the turbine level, simulations are performed to analyze induced structural loads. At the grid level, simulations test a wind plant's response to a dip in grid frequency.

Buckspan, A.; Aho, J.; Pao, L.; Fleming, P.; Jeong, Y.

2012-06-01T23:59:59.000Z

98

Soft-stall control versus furling control for small wind turbine power regulation  

SciTech Connect (OSTI)

Many small wind turbines are designed to furl (turn) in high winds to regulate power and provide overspeed protection. Furling control results in poor energy capture at high wind speeds. This paper proposes an alternative control strategy for small wind turbines -- the soft-stall control method. The furling and soft-stall control strategies are compared using steady state analysis and dynamic simulation analysis. The soft-stall method is found to offer several advantages: increased energy production at high wind speeds, energy production which tracks the maximum power coefficient at low to medium wind speeds, reducing furling noise, and reduced thrust.

Muljadi, E.; Forsyth, T.; Butterfield, C.P.

1998-07-01T23:59:59.000Z

99

Design and Quasi-Equilibrium Analysis of a Distributed Frequency-Restoration Controller for Inverter-Based Microgrids  

SciTech Connect (OSTI)

This paper discusses a proposed frequency restoration controller which operates as an outer loop to frequency droop for voltage-source inverters. By quasi-equilibrium analysis, we show that the proposed controller is able to provide arbitrarily small steady-state frequency error while maintaing power sharing between inverters without need for communication or centralized control. We derive rate of convergence, discuss design considerations (including a fundamental trade-off that must be made in design), present a design procedure to meet a maximum frequency error requirement, and show simulation results verifying our analysis and design method. The proposed controller will allow flexible plug-and-play inverter-based networks to meet a specified maximum frequency error requirement.

Ainsworth, Nathan G [ORNL] [ORNL; Grijalva, Prof. Santiago [Georgia Institute of Technology, Atlanta] [Georgia Institute of Technology, Atlanta

2013-01-01T23:59:59.000Z

100

Soft-Stall Control versus Furling Control for Small Wind Turbine Power Regulation  

SciTech Connect (OSTI)

Many small wind turbines are designed to furl (turn) in high winds to regulate power and provide overspeed protection. Furling control results in poor energy capture at high wind speeds. This paper proposes an alternative control strategy for small wind turbines -- the soft-stall method. The furling and soft-stall control strategies are compared using steady state analysis and dynamic simulation analysis. The soft-stall method is found to offer several advantages: increased energy production at high wind speeds, energy production which tracks the maximum power coefficient at low to medium wind speeds, reduced furling noise, and reduced thrust.

Muljadi, E.; Forsyth, T.; Butterfield, C. P.

1998-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "turbine controllers inverters" 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

Robust and fault-tolerant linear parameter-varying control of wind turbines Christoffer Sloth a,,1  

E-Print Network [OSTI]

Robust and fault-tolerant linear parameter-varying control of wind turbines Christoffer Sloth a,,1 Keywords: Wind turbine control Linear parameter-varying (LPV) control Fault-tolerant control Robust control a b s t r a c t High performance and reliability are required for wind turbines to be competitive

Hansen, René Rydhof

102

Flow Characteristics Analysis of Widows' Creek Type Control Valve for Steam Turbine Control  

SciTech Connect (OSTI)

The steam turbine converts the kinetic energy of steam to mechanical energy of rotor blades in the power conversion system of fossil and nuclear power plants. The electric output from the generator of which the rotor is coupled with that of the steam turbine depends on the rotation velocity of the steam turbine bucket. The rotation velocity is proportional to the mass flow rate of steam entering the steam turbine through valves and nozzles. Thus, it is very important to control the steam mass flow rate for the load following operation of power plants. Among various valves that control the steam turbine, the control valve is most significant. The steam flow rate is determined by the area formed by the stem disk and the seat of the control valve. While the ideal control valve linearly controls the steam mass flow rate with its stem lift, the real control valve has various flow characteristic curves pursuant to the stem lift type. Thus, flow characteristic curves are needed to precisely design the control valves manufactured for the operating conditions of nuclear power plants. OMEGA (Optimized Multidimensional Experiment Geometric Apparatus) was built to experimentally study the flow characteristics of steam flowing inside the control valve. The Widows' Creek type control valve was selected for reference. Air was selected as the working fluid in the OMEGA loop to exclude the condensation effect in this simplified approach. Flow characteristic curves were plotted by calculating the ratio of the measured mass flow rate versus the theoretical mass flow rate of the air. The flow characteristic curves are expected to be utilized to accurately design and operate the control valve for fossil as well as nuclear plants. (authors)

Yoo, Yong H.; Sohn, Myoung S.; Suh, Kune Y. [PHILOSOPHIA, Inc., Seoul National University, San 56-1 Sillim-dong, Gwanak-gu, Seoul, 151-742 (Korea, Republic of)

2006-07-01T23:59:59.000Z

103

Turbines  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLas ConchasPassiveSubmittedStatusButlerTransportation6/14/11 Page 1 of 17Turbines Hydrogen

104

DFIG-Based Wind Turbine Robust Control Using High-Order Sliding Modes and a High Gain Observer  

E-Print Network [OSTI]

DFIG-Based Wind Turbine Robust Control Using High-Order Sliding Modes and a High Gain Observer with the power generation control in variable speed wind turbines. In this context, a control strategy is proposed to ensure power extraction optimization of a DFIG- based wind turbine. The proposed control

Brest, Université de

105

Methods and apparatus for rotor load control in wind turbines  

DOE Patents [OSTI]

A wind turbine having a rotor, at least one rotor blade, and a plurality of generators, of which a first generator is configured to provide power to an electric grid and a second generator is configured to provide power to the wind turbine during times of grid loss. The wind turbine is configured to utilize power provided by the second generator to reduce loads on the wind turbine during times of grid loss.

Moroz, Emilian Mieczyslaw

2006-08-22T23:59:59.000Z

106

Wind turbine control systems: Dynamic model development using system identification and the fast structural dynamics code  

SciTech Connect (OSTI)

Mitigating the effects of damaging wind turbine loads and responses extends the lifetime of the turbine and, consequently, reduces the associated Cost of Energy (COE). Active control of aerodynamic devices is one option for achieving wind turbine load mitigation. Generally speaking, control system design and analysis requires a reasonable dynamic model of {open_quotes}plant,{close_quotes} (i.e., the system being controlled). This paper extends the wind turbine aileron control research, previously conducted at the National Wind Technology Center (NWTC), by presenting a more detailed development of the wind turbine dynamic model. In prior research, active aileron control designs were implemented in an existing wind turbine structural dynamics code, FAST (Fatigue, Aerodynamics, Structures, and Turbulence). In this paper, the FAST code is used, in conjunction with system identification, to generate a wind turbine dynamic model for use in active aileron control system design. The FAST code is described and an overview of the system identification technique is presented. An aileron control case study is used to demonstrate this modeling technique. The results of the case study are then used to propose ideas for generalizing this technique for creating dynamic models for other wind turbine control applications.

Stuart, J.G.; Wright, A.D.; Butterfield, C.P.

1996-10-01T23:59:59.000Z

107

Fuel control for gas turbine with continuous pilot flame  

DOE Patents [OSTI]

An improved fuel control for a gas turbine engine having a continuous pilot flame and a fuel distribution system including a pump drawing fuel from a source and supplying a line to the main fuel nozzle of the engine, the improvement being a control loop between the pump outlet and the pump inlet to bypass fuel, an electronically controlled throttle valve to restrict flow in the control loop when main nozzle demand exists and to permit substantially unrestricted flow without main nozzle demand, a minimum flow valve in the control loop downstream of the throttle valve to maintain a minimum pressure in the loop ahead of the flow valve, a branch tube from the pilot flame nozzle to the control loop between the throttle valve and the minimum flow valve, an orifice in the branch tube, and a feedback tube from the branch tube downstream of the orifice to the minimum flow valve, the minimum flow valve being operative to maintain a substantially constant pressure differential across the orifice to maintain constant fuel flow to the pilot flame nozzle.

Swick, Robert M. (Indianapolis, IN)

1983-01-01T23:59:59.000Z

108

Developement of a digitally controlled low power single phase inverter for grid connected solar panel.  

E-Print Network [OSTI]

?? The work consists in developing a power conversion unit for solar panel connected to the grid. This unit will be a single phase inverter (more)

Marguet, Raphael

2010-01-01T23:59:59.000Z

109

Power Smoothing and Limitation Control of a PMSG-Based Marine Current Turbine under Swell Waves  

E-Print Network [OSTI]

Power Smoothing and Limitation Control of a PMSG-Based Marine Current Turbine under Swell Waves la puissance maximale (MPPT) nécessiterait d'accélérer ou de décélérer fréquemment la turbine à par une turbine marine associée à un générateur synchrone à aimants permanents (GSAP). Un algorithme

Boyer, Edmond

110

Inverter VAR Control for Distribution Systems with Masoud Farivar, Christopher R. Clarke, Steven H. Low , K. Mani Chandy  

E-Print Network [OSTI]

in [8], [9]. In Section IV, we present a simulation study of a real-world distribution circ solvable. Simulations of a real-world distribution circuit illustrates that the proposed inverter control by Southern California Edison's (SCE) plan to install 500MW of large commercial rooftop PV plants (each

Low, Steven H.

111

A Dual Model-Free Control of Underactuated Mechanical Systems, Application to The Inertia Wheel Inverted Pendulum  

E-Print Network [OSTI]

A Dual Model-Free Control of Underactuated Mechanical Systems, Application to The Inertia Wheel underac- tuated mechanical system: the inertia wheel inverted pendulum. Numerical simulations as well: the ball and beam [9] (where the dynamics of the beam has not been taken into account) and the Planar

Paris-Sud XI, Université de

112

Control strategy of a variable speed wind turbine with multipole permanent magnet synchronous generator  

E-Print Network [OSTI]

values. Keywords: permanent magnet synchronous generator, variable speed wind turbine, direct driven wind). A multipole synchronous generator connected to a power converter can operate at low speeds, so that a gear canControl strategy of a variable speed wind turbine with multipole permanent magnet synchronous

113

Design, modelling and control of a gas turbine air compressor .  

E-Print Network [OSTI]

??The production of compressed air constitutes a considerable portion of industrial electrical consumption. An alternative to electrically driven air compression systems is a gas turbine (more)

WIESE, ASHLEY PETER

2014-01-01T23:59:59.000Z

114

Design and Test of a Vertical-Axis Wind Turbine with Pitch Control J. J. Miau1,a  

E-Print Network [OSTI]

Design and Test of a Vertical-Axis Wind Turbine with Pitch Control J. J. Miau1,a , S. Y. Liang2 , R, USA a jjmiau@mail.ncku.edu.tw Keywords: vertical-axis wind turbine, pitch control, wind of a small vertical-axis wind turbine. Benefits gained can be shown by the experimental and numerical results

Leu, Tzong-Shyng "Jeremy"

115

Load Reduction of Wind Turbines Using Receding Horizon Control Mohsen Soltani, Rafael Wisniewski, Per Brath, and Stephen Boyd  

E-Print Network [OSTI]

Load Reduction of Wind Turbines Using Receding Horizon Control Mohsen Soltani, Rafael Wisniewski, Per Brath, and Stephen Boyd Abstract-- Large scale wind turbines are lightly damped mechanical% respectively, when compared to a conventional controller. I. INTRODUCTION The size of wind turbine structures

116

Abstract--Modelling and control of gas turbines (GTs) have always been a controversial issue because of the complex  

E-Print Network [OSTI]

Abstract--Modelling and control of gas turbines (GTs) have always been a controversial issue that there is no end to the efforts for performance optimization of gas turbines. A variety of analytical and experimental models as well as control systems has been built so far for gas turbines. However, the need

Sainudiin, Raazesh

117

An approach to the development and analysis of wind turbine control algorithms  

SciTech Connect (OSTI)

The objective of this project is to develop the capability of symbolically generating an analytical model of a wind turbine for studies of control systems. This report focuses on a theoretical formulation of the symbolic equations of motion (EOMs) modeler for horizontal axis wind turbines. In addition to the power train dynamics, a generic 7-axis rotor assembly is used as the base model from which the EOMs of various turbine configurations can be derived. A systematic approach to generate the EOMs is presented using d`Alembert`s principle and Lagrangian dynamics. A Matlab M file was implemented to generate the EOMs of a two-bladed, free yaw wind turbine. The EOMs will be compared in the future to those of a similar wind turbine modeled with the YawDyn code for verification. This project was sponsored by Sandia National Laboratories as part of the Adaptive Structures and Control Task. This is the final report of Sandia Contract AS-0985.

Wu, K.C.

1998-03-01T23:59:59.000Z

118

Assessment and Optimization of Lidar Measurement Availability for Wind Turbine Control: Preprint  

SciTech Connect (OSTI)

Turbine-mounted lidars provide preview measurements of the incoming wind field. By reducing loads on critical components and increasing the potential power extracted from the wind, the performance of wind turbine controllers can be improved [2]. As a result, integrating a light detection and ranging (lidar) system has the potential to lower the cost of wind energy. This paper presents an evaluation of turbine-mounted lidar availability. Availability is a metric which measures the proportion of time the lidar is producing controller-usable data, and is essential when a wind turbine controller relies on a lidar. To accomplish this, researchers from Avent Lidar Technology and the National Renewable Energy Laboratory first assessed and modeled the effect of extreme atmospheric events. This shows how a multirange lidar delivers measurements for a wide variety of conditions. Second, by using a theoretical approach and conducting an analysis of field feedback, we investigated the effects of the lidar setup on the wind turbine. This helps determine the optimal lidar mounting position at the back of the nacelle, and establishes a relationship between availability, turbine rpm, and lidar sampling time. Lastly, we considered the role of the wind field reconstruction strategies and the turbine controller on the definition and performance of a lidar's measurement availability.

Davoust, S.; Jehu, A.; Bouillet, M.; Bardon, M.; Vercherin, B.; Scholbrock, A.; Fleming, P.; Wright, A.

2014-05-01T23:59:59.000Z

119

Damage Modeling and Life Extending Control of a Boiler-Turbine System1  

E-Print Network [OSTI]

Damage Modeling and Life Extending Control of a Boiler-Turbine System1 Donglin Li Tongwen Chen2 hierarchical LEC structure and apply it to a typ- ical boiler system. There are two damage models

Marquez, Horacio J.

120

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

SciTech Connect (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] [ORNL; Su, Gui-Jia [ORNL] [ORNL

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "turbine controllers inverters" 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

Advanced turbine systems sensors and controls needs assessment study. Final report  

SciTech Connect (OSTI)

The Instrumentation and Controls Division of the Oak Ridge National Laboratory performed an assessment of the sensors and controls needs for land-based advanced gas turbines being designed as a part of the Department of Energy`s (DOE`s) Advanced Turbine Systems (ATS) Program for both utility and industrial applications. The assessment included visits to five turbine manufacturers. During these visits, in-depth discussions were held with design and manufacturing staff to obtain their views regarding the need for new sensors and controls for their advanced turbine designs. The Unsteady Combustion Facilities at the Morgantown Energy Technology Center was visited to assess the need for new sensors for gas turbine combustion research. Finally, a workshop was conducted at the South Carolina Energy Research and Development Center which provided a forum for industry, laboratory, and university engineers to discuss and prioritize sensor and control needs. The assessment identified more than 50 different measurement, control, and monitoring needs for advanced turbines that cannot currently be met from commercial sources. While all the identified needs are important, some are absolutely critical to the success of the ATS Program.

Anderson, R.L.; Fry, D.N.; McEvers, J.A.

1997-02-01T23:59:59.000Z

122

On Zero Steady-State Error Voltage Control of Single-Phase PWM Inverters With Different Load Types  

SciTech Connect (OSTI)

This paper comprehensively investigates and compares different multiloop linear control schemes for single-phase pulsewidth modulation inverters, both in stationary and synchronous (d-q) frames, by focusing on their steady-state error under different loading conditions. Specifically, it is shown how proportional plus resonant (P + R) control and load current feedback (LCF) control can, respectively, improve the steady-state and transient performance of the inverter, leading to the proposal of a PID + R + LCF control scheme. Furthermore, the LCF control and capacitive current feedback control schemes are shown to be subject to stability issues under second and higher order filter loads. Additionally, the equivalence between the stationary frame and d-q frame controllers is discussed depending on the orthogonal term generation method, and a d-q frame voltage control strategy is proposed eliminating the need for the generation of this orthogonal component. This is achieved while retaining all the advantages of operating in the synchronous d-q frame, i.e., zero steady-state error and ease of implementation. All theoretical findings are validated experimentally using a 1.5 kW laboratory prototype.

Dong, Dong [Virginia Polytechnic Institute and State University (Virginia Tech); Timothy, Thacker [Virginia Polytechnic Institute and State University (Virginia Tech); Burgos, Rolando [ABB; Wang, Fei [ORNL; Boroyevich, Dushan [Virginia Polytechnic Institute and State University (Virginia Tech)

2011-01-01T23:59:59.000Z

123

Refinements and Tests of an Advanced Controller to Mitigate Fatigue Loads in the Controls Advanced Research Turbine: Preprint  

SciTech Connect (OSTI)

Wind turbines are complex, nonlinear, dynamic systems forced by aerodynamic, gravitational, centrifugal, and gyroscopic loads. The aerodynamics of wind turbines are nonlinear, unsteady, and complex. Turbine rotors are subjected to a complicated 3-D turbulent wind inflow field, with imbedded coherent vortices that drive fatigue loads and reduce lifetime. Design of control algorithms for wind turbines must account for multiple control objectives. Future large multi-megawatt turbines must be designed with lighter weight structures, using active controls to mitigate fatigue loads, while maximizing energy capture. Active damping should be added to these dynamic structures to maintain stability for operation in a complex environment. At the National Renewable Energy Laboratory (NREL), we have designed, implemented, and tested advanced controls to maximize energy extraction and reduce structural dynamic loads. These control designs are based on linear models of the turbine that are generated by specialized modeling software. In this paper, we present field test results of an advanced control algorithm to mitigate blade, tower, and drivetrain loads in Region 3.

Wright, A.; Fleming, P.

2010-12-01T23:59:59.000Z

124

Low Order Decentralized Stabilizing Controller Design for a Mobile Inverted Pendulum Robot  

E-Print Network [OSTI]

model is based on a form of an inverted pendulum and the robot was constructed into a mechanical system a schematic using Newton's laws of motion (e.g., [3]). The system has six states describing its motion-axis characterized by the yaw angle and yaw velocity . Any motion about the x-axis is considered negligible

Gundes, A. N.

125

Assessment and Optimization of Lidar Measurement Availability for Wind Turbine Control (Poster)  

SciTech Connect (OSTI)

Integrating Lidar to improve wind turbine controls is a potential breakthrough for reducing the cost of wind energy. By providing undisturbed wind measurements up to 400m in front of the rotor, Lidar may provide an accurate update of the turbine inflow with a preview time of several seconds. Focusing on loads, several studies have evaluated potential reductions using integrated Lidar, either by simulation or full scale field testing.

Scholbrock, F. A.; Fleming, P.; Wright, A.; Davoust, S.; Jehu, A.; Bouillet, M.; Bardon M.; Vercherin, B.

2014-02-01T23:59:59.000Z

126

Method and apparatus for wind turbine air gap control  

DOE Patents [OSTI]

Methods and apparatus for assembling a wind turbine generator are provided. The wind turbine generator includes a core and a plurality of stator windings circumferentially spaced about a generator longitudinal axis, a rotor rotatable about the generator longitudinal axis wherein the rotor includes a plurality of magnetic elements coupled to a radially outer periphery of the rotor such that an airgap is defined between the stator windings and the magnetic elements and the plurality of magnetic elements including a radially inner periphery having a first diameter. The wind turbine generator also includes a bearing including a first member in rotatable engagement with a radially inner second member, the first member including a radially outer periphery, a diameter of the radially outer periphery of the first member being substantially equal to the first diameter, the rotor coupled to the stator through the bearing such that a substantially uniform airgap is maintained.

Grant, James Jonathan; Bagepalli, Bharat Sampathkumaran; Jansen, Patrick Lee; DiMascio, Paul Stephen; Gadre, Aniruddha Dattatraya; Qu, Ronghai

2007-02-20T23:59:59.000Z

127

Self Adaptive Air Turbine for Wave Energy Conversion Using Shutter Valve and OWC Heoght Control System  

SciTech Connect (OSTI)

An oscillating water column (OWC) is one of the most technically viable options for converting wave energy into useful electric power. The OWC system uses the wave energy to push or pull air through a high-speed turbine, as illustrated in Figure 1. The turbine is typically a bi-directional turbine, such as a Wells turbine or an advanced Dennis-Auld turbine, as developed by Oceanlinx Ltd. (Oceanlinx), a major developer of OWC systems and a major collaborator with Concepts NREC (CN) in Phase II of this STTR effort. Prior to awarding the STTR to CN, work was underway by CN and Oceanlinx to produce a mechanical linkage mechanism that can be cost-effectively manufactured, and can articulate turbine blades to improve wave energy capture. The articulation is controlled by monitoring the chamber pressure. Funding has been made available from the U.S. Department of Energy (DOE) to CN (DOE DE-FG-08GO18171) to co-share the development of a blade articulation mechanism for the purpose of increasing energy recovery. However, articulating the blades is only one of the many effective design improvements that can be made to the composite subsystems that constitute the turbine generator system.

Di Bella, Francis A

2014-09-29T23:59:59.000Z

128

Wind Turbine Control Design to Reduce Capital Costs: 7 January 2009 - 31 August 2009  

SciTech Connect (OSTI)

This report first discusses and identifies which wind turbine components can benefit from advanced control algorithms and also presents results from a preliminary loads case analysis using a baseline controller. Next, it describes the design, implementation, and simulation-based testing of an advanced controller to reduce loads on those components. The case-by-case loads analysis and advanced controller design will help guide future control research.

Darrow, P. J.

2010-01-01T23:59:59.000Z

129

Invert Recommendations The Invert project  

E-Print Network [OSTI]

­ Polish Foundation for Energy Efficiency, Poland - FhG-ISI ­ Fraunhofer Institute for Systems and Innovation Research, Germany Contact/Information: Lukas.Kranzl@tuwien.ac.at www.invert.at Imprint: Energy

130

Vindicator Lidar Assessment for Wind Turbine Feed-Forward Control Applications: Cooperative Research and Development Final Report, CRADA Number CRD-09-352  

SciTech Connect (OSTI)

Collaborative development and testing of feed-forward and other advanced wind turbine controls using a laser wind sensor.

Wright, A.

2014-01-01T23:59:59.000Z

131

Abstract--This paper addresses the problem of controlling wind energy conversion systems (WECS) which involve  

E-Print Network [OSTI]

Abstract-- This paper addresses the problem of controlling wind energy conversion systems (WECS-inverter. The goal of control is to maximize wind energy extraction and this needs letting the wind turbine rotor wind energy extraction) only for one wind speed value depending on the considered value of turbine

Paris-Sud XI, Université de

132

Ris-R-1117(EN) Power Control for Wind Turbines in  

E-Print Network [OSTI]

Risø-R-1117(EN) Power Control for Wind Turbines in Weak Grids: Project summary Henrik Bindner (Ed in Europe large areas exist where the wind resources are good or very good and the grid is relatively weak for the exploitation of the wind resource. There are two main problems concerned with wind power and weak grids

133

Modeling and Control of a Marine Current Turbine Driven Doubly-Fed Induction Generator  

E-Print Network [OSTI]

--Marine current turbine, Doubly-Fed Induction Generator, modeling, control, Maximum Power Point Tracking current speed; = Tip speed ratio; s, (r) = Stator (rotor) index (superscripts); d, q = Synchronous leakage coefficient, = 1 ­ M2 /LsLr; r = Rotor position; (s) = Rotor electrical speed (electrical

Boyer, Edmond

134

Field Test Results from Lidar Measured Yaw Control for Improved Yaw Alignment with the NREL Controls Advanced Research Turbine: Preprint  

SciTech Connect (OSTI)

This paper describes field tests of a light detection and ranging (lidar) device placed forward looking on the nacelle of a wind turbine and used as a wind direction measurement to directly control the yaw position of a wind turbine. Conventionally, a wind turbine controls its yaw direction using a nacelle-mounted wind vane. If there is a bias in the measurement from the nacelle-mounted wind vane, a reduction in power production will be observed. This bias could be caused by a number of issues such as: poor calibration, electromagnetic interference, rotor wake, or other effects. With a lidar mounted on the nacelle, a measurement of the wind could be made upstream of the wind turbine where the wind is not being influenced by the rotor's wake or induction zone. Field tests were conducted with the lidar measured yaw system and the nacelle wind vane measured yaw system. Results show that a lidar can be used to effectively measure the yaw error of the wind turbine, and for this experiment, they also showed an improvement in power capture because of reduced yaw misalignment when compared to the nacelle wind vane measured yaw system.

Scholbrock, A.; Fleming, P.; Wright, A.; Slinger, C.; Medley, J.; Harris, M.

2014-12-01T23:59:59.000Z

135

Performance of a Dynamically Controlled Inverter in a Photovoltaic System Interconnected with a Secondary Network Distribution System  

SciTech Connect (OSTI)

In 2008, a 300 kW{sub peak} photovoltaic (PV) system was installed on the rooftop of the Colorado Convention Center (CCC). The installation was unique for the electric utility, Xcel Energy, as it had not previously permitted a PV system to be interconnected on a building served by the local secondary network distribution system (network). The PV system was installed with several provisions; one to prevent reverse power flow, another called a dynamically controlled inverter (DCI), that curtails the output of the PV inverters to maintain an amount of load supplied by Xcel Energy at the CCC. The DCI system utilizes current transformers (CTs) to sense power flow to insure that a minimum threshold is maintained from Xcel Energy through the network transformers. The inverters are set to track the load on each of the three phases and curtail power from the PV system when the generated PV system current reaches 95% of the current on any phase. This is achieved by the DCI, which gathers inputs from current transformers measuring the current from the PV array, Xcel, and the spot network load. Preventing reverse power flow is a critical technical requirement for the spot network which serve this part of the CCC. The PV system was designed with the expectation that the DCI system would not curtail the PV system, as the expected minimum load consumption was historically higher than the designed PV system size. However, the DCI system has operated many days during the course of a year, and the performance has been excellent. The DCI system at the CCC was installed as a secondary measure to insure that a minimum level of power flows to the CCC from the Xcel Energy network. While this DCI system was intended for localized control, the system could also reduce output percent if an external smart grid control signal was employed. This paper specifically focuses on the performance of the innovative design at this installation; however, the DCI system could also be used for new s- art grid-enabled distribution systems where renewables power contributions at certain conditions or times may need to be curtailed.

Coddington, M. H.; Kroposki, B. D.; Basso, T.; Berger, D.; Crowell, K.; Hayes, J.

2011-01-01T23:59:59.000Z

136

Electrical system for pulse-width modulated control of a power inverter using phase-shifted carrier signals and related operating methods  

DOE Patents [OSTI]

Systems and methods are provided for pulse-width modulated control of power inverter using phase-shifted carrier signals. An electrical system comprises an energy source and a motor. The motor has a first set of windings and a second set of windings, which are electrically isolated from each other. An inverter module is coupled between the energy source and the motor and comprises a first set of phase legs coupled to the first set of windings and a second set of phase legs coupled to the second set of windings. A controller is coupled to the inverter module and is configured to achieve a desired power flow between the energy source and the motor by modulating the first set of phase legs using a first carrier signal and modulating the second set of phase legs using a second carrier signal. The second carrier signal is phase-shifted relative to the first carrier signal.

Welchko, Brian A. (Torrance, CA)

2012-02-14T23:59:59.000Z

137

Cost effective designs for integrating new electronic turbine control systems into existing steam power plants  

SciTech Connect (OSTI)

Different cost-effective approaches have been developed for integrating new digital turbine control systems into existing power plants. The devices under consideration range from self contained actuators which replace the existing hydraulic and mechanical servomotor components, linear proportional actuators, which mechanically drive the original servomotor pilot relays, to electro-hydraulic converters which provide a control pressure to the existing hydraulic servomotor pilot relays. These devices significantly reduce the implementation cost, while still providing most of the benefits that can be gained through greater utilization of the new electronic control capabilities. These three design approaches are analyzed for control performance, failure modes, long-term maintenance issues, and applicability to specific turbine configurations.

Nguyen, T.V. [Westinghouse Electric Corp., Orlando, FL (United States)

1996-10-01T23:59:59.000Z

138

Control strategy for variable-speed, stall-regulated wind turbines  

SciTech Connect (OSTI)

A variable-speed, constant-pitch wind turbine was investigated to evaluate the feasibility of constraining its rotor speed and power output without the benefit of active aerodynamic control devices. A strategy was postulated to control rotational speed by specifying the demanded generator torque. By controlling rotor speed in relation to wind speed, the aerodynamic power extracted by the blades from the wind was manipulated. Specifically, the blades were caused to stall in high winds. In low and moderate winds, the demanded generator torque and the resulting rotor speed were controlled to cause the wind turbine to operate near maximum efficiency. A computational model was developed, and simulations were conducted of operation in high turbulent winds. Results indicated that rotor speed and power output were well regulated. 7 refs., 7 figs.

Muljadi, E.; Pierce, K.; Migliore, P.

1998-04-01T23:59:59.000Z

139

MODELING, IDENTIFICATION AND CONTROL, 2006, VOL. 00, NO. 0, 000000 Control Design for a Gas Turbine Cycle with CO2 Capture  

E-Print Network [OSTI]

MODELING, IDENTIFICATION AND CONTROL, 2006, VOL. 00, NO. 0, 000­000 Control Design for a Gas capture The semi-closed oxy-fuel gas turbine cycle has been suggested in (Ulizar and Pilidis, 1997 in Section 2), is based on concept (c) above. The exhaust gas from a gas turbine with CO2 as working fluid

Foss, Bjarne A.

140

A new coordinated control strategy for boiler-turbine system of coal-fired power plant  

SciTech Connect (OSTI)

This paper presents the new development of the boiler-turbine coordinated control strategy using fuzzy reasoning and autotuning techniques. The boiler-turbine system is a very complex process that is a multivariable, nonlinear, slowly time-varying plant with large settling time and a lot of uncertainties. As there exist strong couplings between the main steam pressure control loop and the power output control loop in the boiler-turbine unit with large time-delay and uncertainties, automatic coordinated control of the two loops is a very challenging problem. This paper presents a new coordinated control strategy (CCS) which is organized into two levels: a basic control level and a high supervision level. Proportional-integral derivative (PID) type controllers are used in the basic level to perform basic control functions while the decoupling between two control loops can be realized in the high level. A special subclass of fuzzy inference systems, called the Gaussian partition with evenly (GPE) spaced midpoints systems, is used to self-tune the main steam pressure PID controller's parameters online based on the error signal and its first difference, aimed at overcoming the uncertainties due to changing fuel calorific value, machine wear, contamination of the boiler heating surfaces and plant modeling errors. For the large variation of operating condition, a supervisory control level has been developed by autotuning technique. The developed CCS has been implemented in a power plant in China, and satisfactory industrial operation results demonstrate that the proposed control strategy has enhanced the adaptability and robustness of the process. Indeed, better control performance and economic benefit have been achieved.

Li, S.Y.; Liu, H.B.; Cai, W.J.; Soh, Y.C.; Xie, L.H. [Shanghai Jiao Tong University, Shanghai (China)

2005-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "turbine controllers inverters" 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

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

SciTech Connect (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

142

A conservative control strategy for variable-speed stall-regulated wind turbines  

SciTech Connect (OSTI)

Simulation models of a variable-speed, fixed-pitch wind turbine were investigated to evaluate the feasibility of constraining rotor speed and power output without the benefit of active aerodynamic control devices. A strategy was postulated to control rotational speed by specifying the demanded generator torque. By controlling rotor speed in relation to wind speed, the aerodynamic power extracted by the blades from the wind was manipulated. Specifically, the blades were caused to stall in high winds. In low and moderate winds, the demanded generator torque and the resulting rotor speed were controlled to cause the wind turbine to operate near maximum efficiency. Using the developed models, simulations were conducted of operation in turbulent winds. Results indicated that rotor speed and power output were well regulated. Preliminary investigations of system dynamics showed that, compared to fixed-speed operation, variable-speed operation caused cyclic loading amplitude to be reduced for the turbine blades and low-speed shaft and slightly increased for the tower loads. This result suggests a favorable impact on fatigue life from implementation of the proposed control strategy.

Muljadi, E.; Pierce, K.; Migliore, P.

2000-02-08T23:59:59.000Z

143

An Improved Fault-Tolerant Control Scheme for PWM Inverter-Fed Induction Motor-Based EVs  

E-Print Network [OSTI]

and simulations on an electric vehicle are carried-out using a European urban driving cycle to show for such systems. In particular, voltage source inverters are a key component of these electric motor drive systems of an electric vehicle on the variable-speed ac drives and particularly on the power inverter is rapidly

Paris-Sud XI, Université de

144

Synchronization and Power Sharing for Droop-Controlled Inverters in Islanded Microgrids  

E-Print Network [OSTI]

. Simpson-Porco, Florian D¨orfler, Francesco Bullo a a Center for Control, Dynamical Systems. Simpson-Porco), dorfler@engineering.ucsb.edu (Florian D¨orfler), bullo@engineering.ucsb.edu (Francesco

Bullo, Francesco

145

Vertical axis wind turbine  

SciTech Connect (OSTI)

Wind turbines are largely divided into vertical axis wind turbines and propeller (Horizontal axis) wind turbines. The present invention discloses a vertical axis high speed wind turbine provided with rotational speed control systems. This vertical axis wind turbine is formed by having blades of a proper airfoil fitted to respective supporting arms provided radially from a vertical rotating shaft by keeping the blade span-wise direction in parallel with the shaft and being provided with aerodynamic control elements operating manually or automatically to control the rotational speed of the turbine.

Kato, Y.; Seki, K.; Shimizu, Y.

1981-01-27T23:59:59.000Z

146

Acoustic noise associated with the MOD-1 wind turbine: its source, impact, and control  

SciTech Connect (OSTI)

This report summarizes extensive research by staff of the Solar Energy Research Institute and its subcontractors conducted to establish the origin and possible amelioration of acoustic disturbances associated with the operation of the DOE/NASA MOD-1 wind turbine installed in 1979 near Boone, North Carolina. Results have shown that the source of this acoustic annoyance was the transient, unsteady aerodynamic lift imparted to the turbine blades as they passed through the lee wakes of the large, cylindrical tower supports. Nearby residents were annoyed by the low-frequency, acoustic impulses propagated into the structures in which the complainants lived. The situation was aggravated further by a complex sound propagation process controlled by terrain and atmospheric focusing. Several techniques for reducing the abrupt, unsteady blade load transients were researched and are discussed in the report.

Kelley, N.D.; McKenna, H.E.; Hemphill, R.R.; Etter, C.L.; Garrelts, R.L.; Linn, N.C.

1985-02-01T23:59:59.000Z

147

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

SciTech Connect (OSTI)

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

148

System and method for regulating resonant inverters  

DOE Patents [OSTI]

A technique is provided for direct digital phase control of resonant inverters based on sensing of one or more parameters of the resonant inverter. The resonant inverter control system includes a switching circuit for applying power signals to the resonant inverter and a sensor for sensing one or more parameters of the resonant inverter. The one or more parameters are representative of a phase angle. The resonant inverter control system also includes a comparator for comparing the one or more parameters to a reference value and a digital controller for determining timing of the one or more parameters and for regulating operation of the switching circuit based upon the timing of the one or more parameters.

Stevanovic, Ljubisa Dragoljub (Clifton Park, NY); Zane, Regan Andrew (Superior, CO)

2007-08-28T23:59:59.000Z

149

Power Smoothing Control in a Grid-Connected Marine Current Turbine System for Compensating  

E-Print Network [OSTI]

similar principles in wind generation systems can be applied in marine current turbine (MCT) systems due

Boyer, Edmond

150

Power inverters  

DOE Patents [OSTI]

Power inverters include a frame and a power module. The frame has a sidewall including an opening and defining a fluid passageway. The power module is coupled to the frame over the opening and includes a substrate, die, and an encasement. The substrate includes a first side, a second side, a center, an outer periphery, and an outer edge, and the first side of the substrate comprises a first outer layer including a metal material. The die are positioned in the substrate center and are coupled to the substrate first side. The encasement is molded over the outer periphery on the substrate first side, the substrate second side, and the substrate outer edge and around the die. The encasement, coupled to the substrate, forms a seal with the metal material. The second side of the substrate is positioned to directly contact a fluid flowing through the fluid passageway.

Miller, David H. (Redondo Beach, CA); Korich, Mark D. (Chino Hills, CA); Smith, Gregory S. (Woodland Hills, CA)

2011-11-15T23:59:59.000Z

151

Multivariable Robust Control of a Simulated Hybrid Solid Oxide Fuel Cell Gas Turbine Plant  

SciTech Connect (OSTI)

This paper presents a systematic approach to the multivariable robust control of a hybrid fuel cell gas turbine plant. The hybrid configuration under investigation comprises a physical simulation of a 300kW fuel cell coupled to a 120kW auxiliary power unit single spool gas turbine. The facility provides for the testing and simulation of different fuel cell models that in turn help identify the key issues encountered in the transient operation of such systems. An empirical model of the facility consisting of a simulated fuel cell cathode volume and balance of plant components is derived via frequency response data. Through the modulation of various airflow bypass valves within the hybrid configuration, Bode plots are used to derive key input/output interactions in Transfer Function format. A multivariate system is then built from individual transfer functions, creating a matrix that serves as the nominal plant in an H-Infinity robust control algorithm. The controllers main objective is to track and maintain hybrid operational constraints in the fuel cells cathode airflow, and the turbo machinery states of temperature and speed, under transient disturbances. This algorithm is then tested on a Simulink/MatLab platform for various perturbations of load and fuel cell heat effluence.

Tsai, Alex; Banta, Larry; Tucker, D.A.; Gemmen, R.S.

2008-06-01T23:59:59.000Z

152

boolean queries Inverted index  

E-Print Network [OSTI]

boolean queries Inverted index query processing Query optimization boolean model September 9, 2014 1 / 39 #12;boolean queries Inverted index query processing Query optimization Outline 1 boolean queries 2 Inverted index 3 query processing 4 Query optimization 2 / 39 #12;boolean queries Inverted index

Lu, Jianguo

153

Modeling and control of an open accumulator Compressed Air Energy Storage (CAES) system for wind turbines q  

E-Print Network [OSTI]

Modeling and control of an open accumulator Compressed Air Energy Storage (CAES) system for wind compressed air energy storage. Maximizes energy production, levels load, downsizes electrical parts, meets presents the modeling and control for a novel Compressed Air Energy Storage (CAES) system for wind turbines

Li, Perry Y.

154

Multivariable Robust Control of a Simulated Hybrid Solid Oxide Fuel Cell Gas Turbine Plant  

SciTech Connect (OSTI)

This work presents a systematic approach to the multivariable robust control of a hybrid fuel cell gas turbine plant. The hybrid configuration under investigation built by the National Energy Technology Laboratory comprises a physical simulation of a 300kW fuel cell coupled to a 120kW auxiliary power unit single spool gas turbine. The public facility provides for the testing and simulation of different fuel cell models that in turn help identify the key difficulties encountered in the transient operation of such systems. An empirical model of the built facility comprising a simulated fuel cell cathode volume and balance of plant components is derived via frequency response data. Through the modulation of various airflow bypass valves within the hybrid configuration, Bode plots are used to derive key input/output interactions in transfer function format. A multivariate system is then built from individual transfer functions, creating a matrix that serves as the nominal plant in an H{sub {infinity}} robust control algorithm. The controllers main objective is to track and maintain hybrid operational constraints in the fuel cells cathode airflow, and the turbo machinery states of temperature and speed, under transient disturbances. This algorithm is then tested on a Simulink/MatLab platform for various perturbations of load and fuel cell heat effluence. As a complementary tool to the aforementioned empirical plant, a nonlinear analytical model faithful to the existing process and instrumentation arrangement is evaluated and designed in the Simulink environment. This parallel task intends to serve as a building block to scalable hybrid configurations that might require a more detailed nonlinear representation for a wide variety of controller schemes and hardware implementations.

Tsai A, Banta L, Tucker D

2010-08-01T23:59:59.000Z

155

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

E-Print Network [OSTI]

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

Rivas, Juan M.

156

Friction and the Inverted Pendulum Stabilization Problem Sue Ann Campbell  

E-Print Network [OSTI]

Friction and the Inverted Pendulum Stabilization Problem Sue Ann Campbell Department of Applied. Keywords: inverted pendulum, friction, feedback control, stability analysis. 1 #12;INTRODUCTION to be the cause of failure of a feedback controller to stabilize a three link inverted pendulum system [2

Campbell, Sue Ann

157

Multilevel Inverters for Electric Vehicle Applications  

SciTech Connect (OSTI)

This paper presents multilevel inverters as an application for all-electric vehicle (EV) and hybrid-electric vehicle (HEV) motor drives. Diode-clamped inverters and cascaded H-bridge inverters, (1) can generate near-sinusoidal voltages with only fundamental frequency switching; (2) have almost no electromagnetic interference (EMI) and common-mode voltage; and (3) make an EV more accessible/safer and open wiring possible for most of an EV'S power system. This paper explores the benefits and discusses control schemes of the cascade inverter for use as an EV motor drive or a parallel HEV drive and the diode-clamped inverter as a series HEV motor drive. Analytical, simulated, and experimental results show the superiority of these multilevel inverters for this new niche.

Habetler, T.G.; Peng, F.Z.; Tolbert, L.M.

1998-10-22T23:59:59.000Z

158

Investigation of Dynamic Aerodynamics and Control of Wind Turbine Sections Under Relevant Inflow/Blade Attitude Conditions  

SciTech Connect (OSTI)

The growth of wind turbines has led to highly variable loading on the blades. Coupled with the relative reduced stiffness of longer blades, the need to control loading on the blades has become important. One method of controlling loads and maximizing energy extraction is local control of the flow on the wind turbine blades. The goal of the present work was to better understand the sources of the unsteady loading and then to control them. This is accomplished through an experimental effort to characterize the unsteadiness and the effect of a Gurney flap on the flow, as well as an analytical effort to develop control approaches. It was planned to combine these two efforts to demonstrate control of a wind tunnel test model, but that final piece still remains to be accomplished.

Naughton, Jonathan W. [University of Wyoming

2014-08-05T23:59:59.000Z

159

Vertical axis wind turbine  

SciTech Connect (OSTI)

Wind turbines are largely divided into vertical axis wind turbines and propeller (Horizontal axis) wind turbines. The present invention discloses a vertical axis high speed wind turbine provided with a starting and braking control system. This vertical axis wind turbine is formed by having blades of a proper airfoil fitted to respective supporting arms provided radially from a vertical rotary axis by keeping the blade span-wise direction in parallel with the axis and being provided with a low speed control windmill in which the radial position of each operating piece varies with a centrifugal force produced by the rotation of the vertical rotary axis.

Kato, Y.; Seki, K.; Shimizu, Y.

1981-01-27T23:59:59.000Z

160

Comparing State-Space Multivariable Controls to Multi-SISO Controls for Load Reduction of Drivetrain-Coupled Modes on Wind Turbines through Field-Testing: Preprint  

SciTech Connect (OSTI)

This paper presents the structure of an ongoing controller comparison experiment at NREL's National Wind Technology Center; the design process for the two controllers compared in this phase of the experiment, and initial comparison results obtained in field-testing. The intention of the study is to demonstrate the advantage of using modern multivariable methods for designing control systems for wind turbines versus conventional approaches. We will demonstrate the advantages through field-test results from experimental turbines located at the NWTC. At least two controllers are being developed side-by-side to meet an incrementally increasing number of turbine load-reduction objectives. The first, a multiple single-input, single-output (m-SISO) approach, uses separately developed decoupled and classicially tuned controllers, which is, to the best of our knowledge, common practice in the wind industry. The remaining controllers are developed using state-space multiple-input and multiple-output (MIMO) techniques to explicity account for coupling between loops and to optimize given known frequency structures of the turbine and disturbance. In this first publication from the study, we present the structure of the ongoing controller comparison experiment, the design process for the two controllers compared in this phase, and initial comparison results obtained in field-testing.

Fleming, P. A.; van Wingerden, J. W.; Wright, A. D.

2011-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "turbine controllers inverters" 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

Method of controlling the side wall thickness of a turbine nozzle segment for improved cooling  

DOE Patents [OSTI]

A gas turbine nozzle segment has outer and inner bands and a vane extending therebetween. Each band has a side wall, a cover and an impingement plate between the cover and nozzle wall defining two cavities on opposite sides of the impingement plate. Cooling steam is supplied to one cavity for flow through apertures of the impingement plate to cool the nozzle wall. The side wall of the band has an inturned flange defining with the nozzle wall an undercut region. The outer surface of the side wall is provided with a step prior to welding the cover to the side wall. A thermal barrier coating is applied in the step and, after the cover is welded to the side wall, the side wall is finally machined to a controlled thickness removing all, some or none of the coating.

Burdgick, Steven Sebastian (Schenectady, NY)

2002-01-01T23:59:59.000Z

162

Green Power Inverter Prvningsrapport  

E-Print Network [OSTI]

Green Power Inverter Prøvningsrapport SolenergiCentret Søren Poulsen Ivan Katic Oktober 2004 #12;Green Power Inverter målerapport.doc SolenergiCentret - 04-03-2005 2 Forord Nærværende rapport indeholder Teknologisk Instituts bidrag til målinger i forbindelse med PSO projektet "Green Power Inverter

163

202 IEEE TRANS.4CTIONS Oh'AUTOMATIC CONTROL, VOL. AC-18,NO. 3, J U K E 1973 Design and Analysis of Boiler-Turbine-Generator  

E-Print Network [OSTI]

of Boiler-Turbine-Generator Controls Using Optimal Linear Regulator Theory JOHN P. McDOKALD AND HARRY G of a nonlinear mathematical model of a drum-type, twin furnace, reheat boiler-turbine-generator (RBTG) system- tiveoperatingandcontrolstrategies for boiler-t.urbine- generator systems to meet different, system operating ob- jectives. Among

Kwatny, Harry G.

164

Advanced Power Electronic Interfaces for Distributed Energy Systems, Part 2: Modeling, Development, and Experimental Evaluation of Advanced Control Functions for Single-Phase Utility-Connected Inverter  

SciTech Connect (OSTI)

Integrating renewable energy and distributed generations into the Smart Grid architecture requires power electronic (PE) for energy conversion. The key to reaching successful Smart Grid implementation is to develop interoperable, intelligent, and advanced PE technology that improves and accelerates the use of distributed energy resource systems. This report describes the simulation, design, and testing of a single-phase DC-to-AC inverter developed to operate in both islanded and utility-connected mode. It provides results on both the simulations and the experiments conducted, demonstrating the ability of the inverter to provide advanced control functions such as power flow and VAR/voltage regulation. This report also analyzes two different techniques used for digital signal processor (DSP) code generation. Initially, the DSP code was written in C programming language using Texas Instrument's Code Composer Studio. In a later stage of the research, the Simulink DSP toolbox was used to self-generate code for the DSP. The successful tests using Simulink self-generated DSP codes show promise for fast prototyping of PE controls.

Chakraborty, S.; Kroposki, B.; Kramer, W.

2008-11-01T23:59:59.000Z

165

Development of Steam Turbine Inlet Control Valve for Supercritical Pressure at Siemens Industrial Turbomachinery AB.  

E-Print Network [OSTI]

?? The development in the steam turbine business is heading for applications with much higher steam parameters since this enables a raised efficiency. Steam parameters (more)

Sors, Felix

2010-01-01T23:59:59.000Z

166

Direct modelling of envelope dynamics in resonant inverters  

E-Print Network [OSTI]

Direct modelling of envelope dynamics in resonant inverters Y. Yin, R. Zane, R. Erickson and J. Glaser A direct dynamic modelling approach is proposed for envelope signals in resonant inverters tank and simplify analysis and controller design. Introduction: High-frequency DC-AC inverters

167

Invertibility of Nonlinear Switched Systems Aneel Tanwani and Daniel Liberzon  

E-Print Network [OSTI]

Invertibility of Nonlinear Switched Systems Aneel Tanwani and Daniel Liberzon Abstract-- This article addresses the invertibility problem for switched nonlinear systems affine in controls. The problem and sufficient condition for a switched system to be invertible, which says that the subsystems should

168

Magnetically and electrically tunable semiconductor quantum waveguide inverter  

E-Print Network [OSTI]

Magnetically and electrically tunable semiconductor quantum waveguide inverter M. J. Gilbert,a) R implementations. We present an electrically tunable semiconductor quantum waveguide implementation of an inverter. On the other hand, if a ``0'' is present in the control bit, then the qubit is inverted. In a recent study

Gilbert, Matthew

169

Integrated Inverter For Driving Multiple Electric Machines  

DOE Patents [OSTI]

An electric machine drive (50) has a plurality of inverters (50a, 50b) for controlling respective electric machines (57, 62), which may include a three-phase main traction machine (57) and two-phase accessory machines (62) in a hybrid or electric vehicle. The drive (50) has a common control section (53, 54) for controlling the plurality of inverters (50a, 50b) with only one microelectronic processor (54) for controlling the plurality of inverters (50a, 50b), only one gate driver circuit (53) for controlling conduction of semiconductor switches (S1-S10) in the plurality of inverters (50a, 50b), and also includes a common dc bus (70), a common dc bus filtering capacitor (C1) and a common dc bus voltage sensor (67). The electric machines (57, 62) may be synchronous machines, induction machines, or PM machines and may be operated in a motoring mode or a generating mode.

Su, Gui-Jia [Knoxville, TN; Hsu, John S [Oak Ridge, TN

2006-04-04T23:59:59.000Z

170

Power Electronics and Controls for Wind Turbine F. Blaabjerg, F. Iov, Z. Chen, K. Ma  

E-Print Network [OSTI]

was in the beginning based on a squirrel-cage induction generator connected directly to the grid. Power pulsations technologies used in wind turbine systems. I. INTRODUCTION In classical power systems, large power generation such as wind turbines, wave generators, photovoltaic (PV) generators, small hydro, fuel cells and gas

Chen, Zhe

171

Advanced Modular Inverter Technology Development  

SciTech Connect (OSTI)

Electric and hybrid-electric vehicle systems require an inverter to convert the direct current (DC) output of the energy generation/storage system (engine, fuel cells, or batteries) to the alternating current (AC) that vehicle propulsion motors use. Vehicle support systems, such as lights and air conditioning, also use the inverter AC output. Distributed energy systems require an inverter to provide the high quality AC output that energy system customers demand. Today's inverters are expensive due to the cost of the power electronics components, and system designers must also tailor the inverter for individual applications. Thus, the benefits of mass production are not available, resulting in high initial procurement costs as well as high inverter maintenance and repair costs. Electricore, Inc. (www.electricore.org) a public good 501 (c) (3) not-for-profit advanced technology development consortium assembled a highly qualified team consisting of AeroVironment Inc. (www.aerovironment.com) and Delphi Automotive Systems LLC (Delphi), (www.delphi.com), as equal tiered technical leads, to develop an advanced, modular construction, inverter packaging technology that will offer a 30% cost reduction over conventional designs adding to the development of energy conversion technologies for crosscutting applications in the building, industry, transportation, and utility sectors. The proposed inverter allows for a reduction of weight and size of power electronics in the above-mentioned sectors and is scalable over the range of 15 to 500kW. The main objective of this program was to optimize existing AeroVironment inverter technology to improve power density, reliability and producibility as well as develop new topology to reduce line filter size. The newly developed inverter design will be used in automotive and distribution generation applications. In the first part of this program the high-density power stages were redesigned, optimized and fabricated. One of the main tasks was to design and validate new gate drive circuits to provide the capability of high temp operation. The new power stages and controls were later validated through extensive performance, durability and environmental tests. To further validate the design, two power stages and controls were integrated into a grid-tied load bank test fixture, a real application for field-testing. This fixture was designed to test motor drives with PWM output up to 50kW. In the second part of this program the new control topology based on sub-phases control and interphase transformer technology was successfully developed and validated. The main advantage of this technology is to reduce magnetic mass, loss and current ripple. This report summarizes the results of the advanced modular inverter technology development and details: (1) Power stage development and fabrication (2) Power stage validation testing (3) Grid-tied test fixture fabrication and initial testing (4) Interphase transformer technology development

Adam Szczepanek

2006-02-04T23:59:59.000Z

172

Control methods and valve arrangement for start-up and shutdown of pressurized combustion and gasification systems integrated with a gas turbine  

DOE Patents [OSTI]

A power plant having a system for converting coal to power in a gas turbine comprises a coal fed pressurized circulating bed for converting coal to pressurized gases, a gas turbine having a compressor for pressurizing air for the pressurized circulating bed and expander for receiving and expanding hot combustion gases for powering a generator, a first fast acting valve for controlling the pressurized air, a second fast acting valve means for controlling pressurized gas from the compressor to the expander.

Provol, Steve J. (Carlsbad, CA); Russell, David B. (San Diego, CA); Isaksson, Matti J. (Karhula, FI)

1994-01-01T23:59:59.000Z

173

Passive control features of a small pebble-bed HTR for a gas turbine cycle  

SciTech Connect (OSTI)

A recent study outlines possible variants of the pebble-bed high-temperature reactor characterized by simplifications in design and operation. Common to them all is the passive response of the reactor to a loss-of-coolant accident (LOCA) in which the decay power is transmitted to the environment by thermal conduction and radiation without the danger of overheating the fuel elements. The simplest way of fueling a pebble-bed reactor is the Peu a Peu modus: Reactor operation starts with the core cavity partially filled with fuel elements, and little by little, new elements are loaded to compensate for burnup. At the end, they are unloaded in one step. This fueling modus avoids the handling of irradiated elements over the whole loading period, and devices for the onload unloading are superflouous. A small 20-MW(thermal) Peu a Peu-fueled reactor operating with a gas turbine cycle is introduced in this paper. Beyond the properties mentioned, it is characterized by additional simplifying features: (1) A single loading period is extended over the whole lifetime, i.e., [approximately]20 yr of full-power operation. (2) Passive response to transients is extended to the control of a regular load follow.

Teuchert, E.; Gerwin, H.; Haas, K.A.; Sun, Y. (Kernforschungsanlage Juelich (Germany))

1992-01-01T23:59:59.000Z

174

Controlling a rabbet load and air/oil seal temperatures in a turbine  

DOE Patents [OSTI]

During a standard fired shutdown of a turbine, a loaded rabbet joint between the fourth stage wheel and the aft shaft of the machine can become unloaded causing a gap to occur due to a thermal mismatch at the rabbet joint with the bearing blower turned on. An open or unloaded rabbet could cause the parts to move relative to each other and therefore cause the rotor to lose balance. If the bearing blower is turned off during a shutdown, the forward air/oil seal temperature may exceed maximum design practice criterion due to "soak-back." An air/oil seal temperature above the established maximum design limits could cause a bearing fire to occur, with catastrophic consequences to the machine. By controlling the bearing blower according to an optimized blower profile, the rabbet load can be maintained, and the air/oil seal temperature can be maintained below the established limits. A blower profile is determined according to a thermodynamic model of the system.

Schmidt, Mark Christopher (Niskayuna, NY)

2002-01-01T23:59:59.000Z

175

Four-wall turbine airfoil with thermal strain control for reduced cycle fatigue  

DOE Patents [OSTI]

A turbine airfoil (20B) with a thermal expansion control mechanism that increases the airfoil camber (60, 61) under operational heating. The airfoil has four-wall geometry, including pressure side outer and inner walls (26, 28B), and suction side outer and inner walls (32, 34B). It has near-wall cooling channels (31F, 31A, 33F, 33A) between the outer and inner walls. A cooling fluid flow pattern (50C, 50W, 50H) in the airfoil causes the pressure side inner wall (28B) to increase in curvature under operational heating. The pressure side inner wall (28B) is thicker than walls (26, 34B) that oppose it in camber deformation, so it dominates them in collaboration with the suction side outer wall (32), and the airfoil camber increases. This reduces and relocates a maximum stress area (47) from the suction side outer wall (32) to the suction side inner wall (34B, 72) and the pressure side outer wall (26).

Cambell, Christian X

2013-09-17T23:59:59.000Z

176

Invertible Darboux Transformations  

E-Print Network [OSTI]

For operators of many different kinds it has been proved that (generalized) Darboux transformations can be built using so called Wronskian formulae. Such Darboux transformations are not invertible in the sense that the corresponding mappings of the operator kernels are not invertible. The only known invertible ones were Laplace transformations (and their compositions), which are special cases of Darboux transformations for hyperbolic bivariate operators of order 2. In the present paper we find a criteria for a bivariate linear partial differential operator of an arbitrary order d to have an invertible Darboux transformation. We show that Wronkian formulae may fail in some cases, and find sufficient conditions for such formulae to work.

Ekaterina Shemyakova

2013-01-04T23:59:59.000Z

177

Full operating range robust hybrid control of a coal-fired boiler/turbine unit - article no. 041011  

SciTech Connect (OSTI)

Multi-input-multi-output robust controllers recently designed for the megawatt output/throttle pressure control in a coal-fired power plant boiler/turbine unit have demonstrated performance robustness noticeably superior to that of the currently employed nonlinear PID-based controller. These controllers, however, have been designed only for the range of 150-185 MW around the 185 MW nominal operating point, exhibiting a significant loss of performance in the lower range of 120-150 MW. Through system identification, the reason for this performance loss is demonstrated in the current work to be a pronounced dependence of the boiler/turbine unit steady state gains on the operating point. This problem is addressed via a hybrid control law consisting of two robust controllers and a robust switch between them activated by the set point change. The controllers are designed to cover the corresponding half-ranges of the full operating range. This permits attainment of the desired overall performance as well as reduction of modeling uncertainty induced by the operating point change to approximately 25% of that associated with the previous designs. Robust switching is accomplished through a novel hybrid mode of behavior-robustly controlled discrete transition.

Zheng, K.; Bentsman, J.; Taft, C.W. [University of Illinois, Urbana, IL (United States). Dept. for Engineering Science & Mechanics

2008-07-15T23:59:59.000Z

178

PERFORMANCE ENHANCEMENT OF WIND TURBINE POWER REGULATION BY SWITCHED LINEAR CONTROL  

E-Print Network [OSTI]

W. It is anticipated that the next generation of wind turbines which are presently being developed will include large at high power levels, with a consequent reduction in drive-train loads. It achieves very similar

Duffy, Ken

179

Reliable, Efficient and Cost-Effective Electric Power Converter for Small Wind Turbines Based on AC-link Technology  

SciTech Connect (OSTI)

Grid-tied inverter power electronics have been an Achilles heel of the small wind industry, providing opportunity for new technologies to provide lower costs, greater efficiency, and improved reliability. The small wind turbine market is also moving towards the 50-100kW size range. The unique AC-link power conversion technology provides efficiency, reliability, and power quality advantages over existing technologies, and Princeton Power will adapt prototype designs used for industrial asynchronous motor control to a 50kW small wind turbine design.

Darren Hammell; Mark Holveck; DOE Project Officer - Keith Bennett

2006-08-01T23:59:59.000Z

180

Outline Inverted File Building Compression for Inverted Files Building and Compression Techniques for Inverted  

E-Print Network [OSTI]

Outline Inverted File Building Compression for Inverted Files Building and Compression Techniques for Inverted Files Roi Blanco Dpt. Computing Science, University of A Coruna December 13, 2005 Roi Blanco Building and Compression Techniques for Inverted Files #12;Outline Inverted File Building Compression

Barreiro, Alvaro

Note: This page contains sample records for the topic "turbine controllers inverters" 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

Abstract-A hybrid cascaded multilevel inverter application for renewable energy resources including a reconfiguration  

E-Print Network [OSTI]

be achieved by using the microgrid concept as discussed in [2]. Data center or telecommunication buildings an alternative topology of hybrid cascaded multilevel inverter applied to a low voltage dc microgrid, micro-turbine, wind turbine and fuel cell put forward many promising applications with high efficiency

Tolbert, Leon M.

182

Effective switching frequency multiplier inverter  

DOE Patents [OSTI]

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

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

2007-08-07T23:59:59.000Z

183

Real-Time Optimization of Dead Time for Motor Control Inverters 0-7803-3840-5/97/$10.000 1997 IEEE 597  

E-Print Network [OSTI]

597 JonathanKimball Motorola, Inc. Semiconductor Products Sector Phoenix. Arizona Abstract current either to each leg or to the inverter bridge as a whole. This in turn minimizes switching loss power semiconductor device in an inverter or synchronous rectifier application, the objective of dead

Kimball, Jonathan W.

184

Inverted gravity, not inverted shape impairs biological motion perception  

E-Print Network [OSTI]

Inverted gravity, not inverted shape impairs biological motion perception Nikolaus Trojetroje. Scrambling should therefore impair perception even more than inversion. Upright and inverted scrambled motion). Is the cause of the inversion effect inverted gravity? If this is the case upright scrambled motion should

Troje, Nikolaus

185

Robust STATCOM control for the stabilisation of fixed-speed wind turbines during low voltages  

E-Print Network [OSTI]

and rotor- speed instability and more so if the wind turbine is connected to a weak grid. To prevent is still being produced by squirrel-cage induction generators (SCIGs) which are directly connected to the grid and operate at an almost fixed-speed [3]. They are advantageous as wind generators for their low

Pota, Himanshu Roy

186

Voltage/Pitch Control for Maximization and Regulation of Active/Reactive Powers in Wind Turbines with Uncertainties  

E-Print Network [OSTI]

This paper addresses the problem of controlling a variable-speed wind turbine with a Doubly Fed Induction Generator (DFIG), modeled as an electromechanically-coupled nonlinear system with rotor voltages and blade pitch angle as its inputs, active and reactive powers as its outputs, and most of the aerodynamic and mechanical parameters as its uncertainties. Using a blend of linear and nonlinear control strategies (including feedback linearization, pole placement, uncertainty estimation, and gradient-based potential function minimization) as well as time-scale separation in the dynamics, we develop a controller that is capable of maximizing the active power in the Maximum Power Tracking (MPT) mode, regulating the active power in the Power Regulation (PR) mode, seamlessly switching between the two modes, and simultaneously adjusting the reactive power to achieve a desired power factor. The controller consists of four cascaded components, uses realistic feedback signals, and operates without knowledge of the C_p-...

Guo, Yi; Jiang, John N; Tang, Choon Yik; Ramakumar, Rama G

2010-01-01T23:59:59.000Z

187

Hardware Development of a Laboratory-Scale Microgrid Phase 2: Operation and Control of a Two-Inverter Microgrid  

SciTech Connect (OSTI)

This report summarizes the activities of the second year of a three-year project to develop control software for microsource distributed generation systems. In this phase, a laboratory-scale microgrid was expanded to include: (1) Two emulated distributed resources; (2) Static switchgear to allow rapid disconnection and reconnection; (3) Electronic synchronizing circuitry to enable transient-free grid interconnection; (4) Control software for dynamically varying the frequency and voltage controller structures; and (5) Power measurement instrumentation for capturing transient waveforms at the interconnect during switching events.

Illindala, M. S.; Piagi, P.; Zhang, H.; Venkataramanan, G.; Lasseter, R. H.

2004-03-01T23:59:59.000Z

188

44th Aerospace Sciences Meeting and Exhibit, January 9-12, 2006, Reno, Nevada Turbine Tip Clearance Flow Control  

E-Print Network [OSTI]

clearance between the rotor blade tips and outer casing. For a turbine, this clearance is on the order in an engine. In a turbine stage, blade rotation is caused by work extraction through turning of the post44th Aerospace Sciences Meeting and Exhibit, January 9-12, 2006, Reno, Nevada Turbine Tip Clearance

Morris, Scott C.

189

Dynamic analysis of a 5 megawatt offshore floating wind turbine  

E-Print Network [OSTI]

wind turbine. Rating Control Rotor Radius Rated Wind Speed Towerwind turbine is used in this design, however there are slight modifications of the tower.of the tower. Figure 2.3: NREL 5 MW Reference Wind Turbine [

Harriger, Evan Michael

2011-01-01T23:59:59.000Z

190

892 IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS, VOL. 57, NO. 3, MARCH 2010 Hybrid Cascaded H-Bridge Multilevel-Inverter  

E-Print Network [OSTI]

-Bridge Multilevel-Inverter Induction-Motor-Drive Direct Torque Control for Automotive Applications Farid Khoucha cascaded H-bridge multilevel inverter, where each phase of the inverter can be implemented using a dc source, which would be available from fuel cells, batteries, or ultracapacitors. This inverter provides

Brest, Université de

191

Abstract --In this study, elimination of harmonics in a five-level diode-clamped multilevel inverter (DCMLI) has been  

E-Print Network [OSTI]

inverter (DCMLI) has been implemented by using fundamental modulation switching. The proposed method, and multilevel inverter. I. INTRODUCTION The problem of eliminating harmonics in switching inverters has been the focus of research for many years. The current trend of modulation control for multilevel inverters

Tolbert, Leon M.

192

Resonant snubber inverter  

DOE Patents [OSTI]

A resonant, snubber-based, soft switching, inverter circuit achieves lossless switching during dc-to-ac power conversion and power conditioning with minimum component count and size. Current is supplied to the resonant snubber branches solely by the main inverter switches. Component count and size are reduced by use of a single semiconductor switch in the resonant snubber branches. Component count is also reduced by maximizing the use of stray capacitances of the main switches as parallel resonant capacitors. Resonance charging and discharging of the parallel capacitances allows lossless, zero voltage switching. In one embodiment, circuit component size and count are minimized while achieving lossless, zero voltage switching within a three-phase inverter. 14 figs.

Lai, J.S.; Young, R.W. Sr.; Chen, D.; Scudiere, M.B.; Ott, G.W. Jr.; White, C.P.; McKeever, J.W.

1997-06-24T23:59:59.000Z

193

Resonant snubber inverter  

DOE Patents [OSTI]

A resonant, snubber-based, soft switching, inverter circuit achieves lossless switching during dc-to-ac power conversion and power conditioning with minimum component count and size. Current is supplied to the resonant snubber branches solely by the main inverter switches. Component count and size are reduced by use of a single semiconductor switch in the resonant snubber branches. Component count is also reduced by maximizing the use of stray capacitances of the main switches as parallel resonant capacitors. Resonance charging and discharging of the parallel capacitances allows lossless, zero voltage switching. In one embodiment, circuit component size and count are minimized while achieving lossless, zero voltage switching within a three-phase inverter.

Lai, Jih-Sheng (Knoxville, TN); Young, Sr., Robert W. (Oak Ridge, TN); Chen, Daoshen (Knoxville, TN); Scudiere, Matthew B. (Oak Ridge, TN); Ott, Jr., George W. (Knoxville, TN); White, Clifford P. (Knoxville, TN); McKeever, John W. (Oak Ridge, TN)

1997-01-01T23:59:59.000Z

194

Passive Acoustic Detection of Wind Turbine In-Flow Conditions for Active Control and Optimization  

SciTech Connect (OSTI)

Wind is a significant source of energy; however, the human capability to produce electrical energy still has many hurdles to overcome. One of these is the unpredictability of the winds in the atmospheric boundary layer (ABL). The ABL is highly turbulent in both stable and unstable conditions (based on the vertical temperature profile) and the resulting fluctuations can have a dramatic impact on wind turbine operation. Any method by which these fluctuations could be observed, estimated, or predicted could provide a benefit to the wind energy industry as a whole. Based on the fundamental coupling of velocity fluctuations to pressure fluctuations in the nearly incompressible flow in the ABL, This work hypothesizes that a ground-based array of infrasonic pressure transducers could be employed to estimate the vertical wind profile over a height relevant for wind turbines. To analyze this hypothesis, experiments and field deployments were conducted. Wind tunnel experiments were performed for a thick turbulent boundary layer over a neutral or heated surface. Surface pressure and velocity probe measurements were acquired simultaneously. Two field deployments yielded surface pressure data from a 49 element array. The second deployment at the Reese Technology Center in Lubbock, TX, also included data from a smaller aperture, 96-element array and a 200-meter tall meteorological tower. Analysis of the data successfully demonstrated the ability to estimate the vertical velocity profile using coherence data from the pressure array. Also, dynamical systems analysis methods were successful in identifying and tracking a gust type event. In addition to the passive acoustic profiling method, this program also investigated a rapid response Doppler SODAR system, the optimization of wind turbine blades for enhanced power with reduced aeroacoustic noise production, and the implementation of a wireless health monitoring system for the wind turbine blades. Each of these other objectives was met successfully. The use of phase unwrapping applied to SODAR data was found to yield reasonable results for per-pulse measurements. A health monitoring system design analysis was able to demonstrate the ability to use a very small number of sensors to monitor blade health based on the blade's overall structural modes. Most notable was the development of a multi-objective optimization methodology that successfully yielded an aerodynamic blade design that produces greater power output with reduced aerodynamic loading noise. This optimization method could be significant for future design work.

Murray, Nathan E.

2012-03-12T23:59:59.000Z

195

Turbine blade vibration dampening  

DOE Patents [OSTI]

The present turbine wheel assembly increases component life and turbine engine longevity. The combination of the strap and the opening combined with the preestablished area of the outer surface of the opening and the preestablished area of the outer circumferential surface of the strap and the friction between the strap and the opening increases the life and longevity of the turbine wheel assembly. Furthermore, the mass "M" or combined mass "CM" of the strap or straps and the centrifugal force assist in controlling vibrations and damping characteristics.

Cornelius, Charles C. (San Diego, CA); Pytanowski, Gregory P. (San Diego, CA); Vendituoli, Jonathan S. (San Diego, CA)

1997-07-08T23:59:59.000Z

196

Turbine blade vibration dampening  

DOE Patents [OSTI]

The present turbine wheel assembly increases component life and turbine engine longevity. The combination of the strap and the opening combined with the preestablished area of the outer surface of the opening and the preestablished area of the outer circumferential surface of the strap and the friction between the strap and the opening increases the life and longevity of the turbine wheel assembly. Furthermore, the mass ``M`` or combined mass ``CM`` of the strap or straps and the centrifugal force assist in controlling vibrations and damping characteristics. 5 figs.

Cornelius, C.C.; Pytanowski, G.P.; Vendituoli, J.S.

1997-07-08T23:59:59.000Z

197

Wind Turbine Safety and Function Test Report for the Mariah Windspire Wind Turbine  

SciTech Connect (OSTI)

This test was conducted as part of the U.S. Department of Energy's (DOE) Independent Testing project. This project was established to help reduce the barriers to wind energy expansion by providing independent testing results for small wind turbines (SWT). In total, five turbines were tested at the National Wind Technology Center (NWTC) as a part of this project. Safety and function testing is one of up to five tests performed on the turbines, including power performance, duration, noise, and power-quality tests. NWTC testing results provide manufacturers with reports that may be used to meet part of small wind turbine certification requirements. The test equipment includes a Mariah Windspire wind turbine mounted on a monopole tower. L&E Machine manufactured the turbine in the United States. The inverter was manufactured separately by Technology Driven Products in the United States. The system was installed by the NWTC site operations group with guidance and assistance from Mariah Power.

Huskey, A.; Bowen, A.; Jager, D.

2010-07-01T23:59:59.000Z

198

Variable-Speed Wind Turbine Controller Systematic Design Methodology: A Comparison of Non-Linear and Linear Model-Based Designs  

SciTech Connect (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. Traditional controller design generally consists of linearizing a model about an operating point. This step was taken for two different operating points, and the systematic design approach was used. A comparison of the optimal regions selected using the n on-linear model and the two linear models shows similarities. The linearization point selection does, however, affect the turbine performance slightly. Exploitation of the simplicity of the model allows surfaces consisting of operation under a wide range of gain values to be created. This methodology provides a means of visually observing turbine performance based upon the two metrics chosen for this study. Design of a PID controller is simplified, and it is possible to ascertain the best possible combination of controller parameters. The wide, flat surfaces indicate that a PID controller is very robust in this variable-speed wind turbine application.

Hand, M. M.

1999-07-30T23:59:59.000Z

199

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  

SciTech Connect (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

200

Turbine exhaust diffuser with a gas jet producing a coanda effect flow control  

DOE Patents [OSTI]

An exhaust diffuser system and method for a turbine engine includes an inner boundary and an outer boundary with a flow path defined therebetween. The inner boundary is defined at least in part by a hub structure that has an upstream end and a downstream end. The outer boundary may include a region in which the outer boundary extends radially inward toward the hub structure and may direct at least a portion of an exhaust flow in the diffuser toward the hub structure. The hub structure includes at least one jet exit located on the hub structure adjacent to the upstream end of the tail cone. The jet exit discharges a flow of gas substantially tangential to an outer surface of the tail cone to produce a Coanda effect and direct a portion of the exhaust flow in the diffuser toward the inner boundary.

Orosa, John; Montgomery, Matthew

2014-02-11T23:59:59.000Z

Note: This page contains sample records for the topic "turbine controllers inverters" 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

Symmetrical and Asymmetrical H-Bridge Multilevel Inverter for DTC Induction Motor Drive  

E-Print Network [OSTI]

Symmetrical and Asymmetrical H-Bridge Multilevel Inverter for DTC Induction Motor Drive Automotive--Several works have been reported in the literature on multilevel inverters topologies, control techniques drives associated to three-phase multilevel inverter. This paper presents then a comparison study

Paris-Sud XI, Université de

202

On Invertibility of Switched Linear Systems L. Vu and D. Liberzon  

E-Print Network [OSTI]

On Invertibility of Switched Linear Systems L. Vu and D. Liberzon Coordinated Science Laboratory.S.A. Email: {linhvu, liberzon}@control.csl.uiuc.edu Abstract-- We address a new problem--the invertibility. In solving the invertibility problem, we introduce the concept of singular pairs for two systems. We give

Liberzon, Daniel

203

Pulse width modulation inverter with battery charger  

DOE Patents [OSTI]

An inverter is connected between a source of DC power and a three-phase AC induction motor, and a microprocessor-based circuit controls the inverter using pulse width modulation techniques. In the disclosed method of pulse width modulation, both edges of each pulse of a carrier pulse train are equally modulated by a time proportional to sin .theta., where .theta. is the angular displacement of the pulse center at the motor stator frequency from a fixed reference point on the carrier waveform. The carrier waveform frequency is a multiple of the motor stator frequency. The modulated pulse train is then applied to each of the motor phase inputs with respective phase shifts of 120.degree. at the stator frequency. Switching control commands for electronic switches in the inverter are stored in a random access memory (RAM) and the locations of the RAM are successively read out in a cyclic manner, each bit of a given RAM location controlling a respective phase input of the motor. The DC power source preferably comprises rechargeable batteries and all but one of the electronic switches in the inverter can be disabled, the remaining electronic switch being part of a "flyback" DC-DC converter circuit for recharging the battery.

Slicker, James M. (Union Lake, MI)

1985-01-01T23:59:59.000Z

204

New Switches for Utility-Scale Inverters: First In-Class Demonstration of a Completely New Type of SiC Bipolar Switch (15kV-20kV) for Utility-Scale Inverters  

SciTech Connect (OSTI)

Solar ADEPT Project: The SiCLAB is developing a new power switch for utility-scale PV inverters that would improve the performance and significantly reduce the size, weight, and energy loss of PV systems. A power switch controls the electrical energy flowing through an inverter, which takes the electrical current from a PV solar panel and converts it into the type and amount of electricity that is compatible with the electric grid. SiCLAB is using silicon carbide (SiC) semiconductors in its new power switches, which are more efficient than the silicon semiconductors used to conduct electricity in most conventional power switches today. Switches with SiC semiconductors can operate at much higher temperatures, as well as higher voltage and power levels than silicon switches. SiC-based power switches are also smaller than those made with silicon alone, so they result in much smaller and lighter electrical devices. In addition to their use in utility-scale PV inverters, SiCLABs new power switches can also be used in wind turbines, railways, and other smart grid applications.

None

2011-12-31T23:59:59.000Z

205

LIDAR Wind Speed Measurement Analysis and Feed-Forward Blade Pitch Control for Load Mitigation in Wind Turbines: January 2010--January 2011  

SciTech Connect (OSTI)

This report examines the accuracy of measurements that rely on Doppler LIDAR systems to determine their applicability to wind turbine feed-forward control systems and discusses feed-forward control system designs that use preview wind measurements. Light Detection and Ranging (LIDAR) systems are able to measure the speed of incoming wind before it interacts with a wind turbine rotor. These preview wind measurements can be used in feed-forward control systems designed to reduce turbine loads. However, the degree to which such preview-based control techniques can reduce loads by reacting to turbulence depends on how accurately the incoming wind field can be measured. The first half of this report examines the accuracy of different measurement scenarios that rely on coherent continuous-wave or pulsed Doppler LIDAR systems to determine their applicability to feed-forward control. In particular, the impacts of measurement range and angular offset from the wind direction are studied for various wind conditions. A realistic case involving a scanning LIDAR unit mounted in the spinner of a wind turbine is studied in depth with emphasis on choices for scan radius and preview distance. The effects of turbulence parameters on measurement accuracy are studied as well. Continuous-wave and pulsed LIDAR models based on typical commercially available units were used in the studies present in this report. The second half of this report discusses feed-forward control system designs that use preview wind measurements. Combined feedback/feed-forward blade pitch control is compared to industry standard feedback control when simulated in realistic turbulent above-rated winds. The feed-forward controllers are designed to reduce fatigue loads, increasing turbine lifetime and therefore reducing the cost of energy. Three feed-forward designs are studied: non-causal series expansion, Preview Control, and optimized FIR filter. The input to the feed-forward controller is a measurement of incoming wind speeds that could be provided by LIDAR. Non-causal series expansion and Preview Control methods reduce blade root loads but increase tower bending in simulation results. The optimized FIR filter reduces loads overall, keeps pitch rates low, and maintains rotor speed regulation and power capture, while using imperfect wind measurements provided by the spinning continuous-wave LIDAR model.

Dunne, F.; Simley, E.; Pao, L.Y.

2011-10-01T23:59:59.000Z

206

Stabilizing the dual inverted pendulum : a practical approach  

E-Print Network [OSTI]

A dual inverted pendulum system, consisting of two individual pendulums of different lengths on a single cart, was fully designed and implemented as a demonstration of classical control theory. This document contains an ...

Barton, Taylor Wallis

2008-01-01T23:59:59.000Z

207

Electrical Cost Reduction Via Steam Turbine Cogeneration  

E-Print Network [OSTI]

ELECTRICAL COST REDUCTION VIA STEAM TURBINE COGENERATION LYNN B. DI TULLIO, P.E. Project Engineer Ewing Power Systems, Inc. South Deerfield, Mass. ABSTRACT Steam turbine cogeneration is a well established technology which is widely used... mature technology. Steam turbines and engines have been used by industry to cogen erate power since before there were electric utilities. While the technology for turbines, generators and controls has continued to develop there is very little about...

Ewing, T. S.; Di Tullio, L. B.

208

Gas cooled traction drive inverter  

SciTech Connect (OSTI)

The present invention provides a modular circuit card configuration for distributing heat among a plurality of circuit cards. Each circuit card includes a housing adapted to dissipate heat in response to gas flow over the housing. In one aspect, a gas-cooled inverter includes a plurality of inverter circuit cards, and a plurality of circuit card housings, each of which encloses one of the plurality of inverter cards.

Chinthavali, Madhu Sudhan

2013-10-08T23:59:59.000Z

209

Advanced wind turbine with lift cancelling aileron for shutdown  

DOE Patents [OSTI]

An advanced aileron configuration for wind turbine rotors featuring an independent, lift generating aileron connected to the rotor blade. The aileron has an airfoil profile which is inverted relative to the airfoil profile of the main section of the rotor blade. The inverted airfoil profile of the aileron allows the aileron to be used for strong positive control of the rotation of the rotor while deflected to angles within a control range of angles. The aileron functions as a separate, lift generating body when deflected to angles within a shutdown range of angles, generating lift with a component acting in the direction opposite the direction of rotation of the rotor. Thus, the aileron can be used to shut down rotation of the rotor. The profile of the aileron further allows the center of rotation to be located within the envelope of the aileron, at or near the centers of pressure and mass of the aileron. The location of the center of rotation optimizes aerodynamically and gyroscopically induced hinge moments and provides a fail safe configuration.

Coleman, Clint (Warren, VT); Juengst, Theresa M. (Warren, VT); Zuteck, Michael D. (Kemah, TX)

1996-06-18T23:59:59.000Z

210

2.3 Characterizations of Invertible Matrices Theorem 8 (The Invertible Matrix Theorem)  

E-Print Network [OSTI]

2.3 Characterizations of Invertible Matrices Theorem 8 (The Invertible Matrix Theorem) Let true or all false). a. A is an invertible matrix. b. A is row equivalent to In. c. A has n pivot. AT is an invertible matrix. EXAMPLE: Use the Invertible Matrix Theorem to determine if A is invertible, where A 1 3 0

Belykh, Igor

211

Invertible Program Restructurings for Continuing Modular Maintenance  

E-Print Network [OSTI]

Invertible Program Restructurings for Continuing Modular Maintenance Julien Cohen ASCOLA team (EMN in main- tenance with invertible program transformations. We illustrate this on the typical Expression problems with our approach. Keywords-modular maintenance; restructuring; invertible pro- gram

Paris-Sud XI, Université de

212

Current Source Inverters for HEVs and FCVs  

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

weight for inverters. Currently, it contributes - Cost and weight, up to 23% of an inverter - Volume, up to 30% of an inverter * Ability of film capacitors to operate at higher...

213

Control method for turbocharged diesel engines having exhaust gas recirculation  

DOE Patents [OSTI]

A method of controlling the airflow into a compression ignition engine having an EGR and a VGT. The control strategy includes the steps of generating desired EGR and VGT turbine mass flow rates as a function of the desired and measured compressor mass airflow values and exhaust manifold pressure values. The desired compressor mass airflow and exhaust manifold pressure values are generated as a function of the operator-requested fueling rate and engine speed. The EGR and VGT turbine mass flow rates are then inverted to corresponding EGR and VGT actuator positions to achieve the desired compressor mass airflow rate and exhaust manifold pressure. The control strategy also includes a method of estimating the intake manifold pressure used in generating the EGR valve and VGT turbine positions.

Kolmanovsky, Ilya V. (Ypsilanti, MI); Jankovic, Mrdjan J (Birmingham, MI); Jankovic, Miroslava (Birmingham, MI)

2000-03-14T23:59:59.000Z

214

Wind turbine spoiler  

DOE Patents [OSTI]

An aerodynamic spoiler system for a vertical axis wind turbine includes spoilers on the blades initially stored near the rotor axis to minimize drag. A solenoid latch adjacent the central support tower releases the spoilers and centrifugal force causes the spoilers to move up the turbine blades away from the rotor axis, thereby producing a braking effect and actual slowing of the associated wind turbine, if desired. The spoiler system can also be used as an infinitely variable power control by regulated movement of the spoilers on the blades over the range between the undeployed and fully deployed positions. This is done by the use of a suitable powered reel and cable located at the rotor tower to move the spoilers.

Sullivan, William N. (Albuquerque, NM)

1985-01-01T23:59:59.000Z

215

Proceedings of the 2008 International Conference on Electrical Machines Paper ID 1433 Hybrid Cascaded H-Bridge Multilevel Inverter Motor  

E-Print Network [OSTI]

Cascaded H-Bridge Multilevel Inverter Motor Drive DTC Control for Electric Vehicles F. Khoucha1,2 , S reference is then generated using a hybrid cascaded H-bridge multilevel inverter, where each phase of the inverter can be implemented using a DC source, which would be available from fuel cells, batteries

Paris-Sud XI, Université de

216

Voltage grid support of DFIG wind turbines during grid faults Anca D. Hansen1  

E-Print Network [OSTI]

Voltage grid support of DFIG wind turbines during grid faults Anca D. Hansen1 , Gabriele Michalke2) wind turbines address primarily the design of DFIG wind turbine control with special focus on power strategy for DFIG wind turbines, which enhances the fault ride-through capability of DFIG wind turbines

217

36 SEPTEMBER | 2012 WiNd TURbiNE CAPACiTY  

E-Print Network [OSTI]

36 SEPTEMBER | 2012 WiNd TURbiNE CAPACiTY FRONTiER FROM SCAdA ThE WORld hAS SEEN A significant contributor to this growth. The wind turbine generated energy depends on the wind potential and the turbine of wind turbines. Supervi- sory control and data acquisition (SCADA) systems record wind turbine

Kusiak, Andrew

218

Triple inverter pierce oscillator circuit suitable for CMOS  

DOE Patents [OSTI]

An oscillator circuit is disclosed which can be formed using discrete field-effect transistors (FETs), or as a complementary metal-oxide-semiconductor (CMOS) integrated circuit. The oscillator circuit utilizes a Pierce oscillator design with three inverter stages connected in series. A feedback resistor provided in a feedback loop about a second inverter stage provides an almost ideal inverting transconductance thereby allowing high-Q operation at the resonator-controlled frequency while suppressing a parasitic oscillation frequency that is inherent in a Pierce configuration using a "standard" triple inverter for the sustaining amplifier. The oscillator circuit, which operates in a range of 10 50 MHz, has applications for use as a clock in a microprocessor and can also be used for sensor applications.

Wessendorf; Kurt O. (Albuquerque, NM)

2007-02-27T23:59:59.000Z

219

Wind turbine  

DOE Patents [OSTI]

A wind turbine of the type having an airfoil blade (15) mounted on a flexible beam (20) and a pitch governor (55) which selectively, torsionally twists the flexible beam in response to wind turbine speed thereby setting blade pitch, is provided with a limiter (85) which restricts unwanted pitch change at operating speeds due to torsional creep of the flexible beam. The limiter allows twisting of the beam by the governor under excessive wind velocity conditions to orient the blades in stall pitch positions, thereby preventing overspeed operation of the turbine. In the preferred embodiment, the pitch governor comprises a pendulum (65,70) which responds to changing rotor speed by pivotal movement, the limiter comprising a resilient member (90) which engages an end of the pendulum to restrict further movement thereof, and in turn restrict beam creep and unwanted blade pitch misadjustment.

Cheney, Jr., Marvin C. (Glastonbury, CT)

1982-01-01T23:59:59.000Z

220

766 IEEE TRANSACTIONS ON ENERGY CONVERSION, VOL. 24, NO. 3, SEPTEMBER 2009 Anticipatory Control of Wind Turbines With  

E-Print Network [OSTI]

to an even more aggressive expansion, aiming at a 20-fold increase in the wind energy production by the year 2030 [3]. A meaningful way to reduce costs is to optimize the capture of energy from the wind constraints. Maxi- mizing the energy captured from the wind as well as reducing hazardous loads on a turbine

Kusiak, Andrew

Note: This page contains sample records for the topic "turbine controllers inverters" 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

ADVANCED TURBINE SYSTEMS PROGRAM  

SciTech Connect (OSTI)

Natural gas combustion turbines are rapidly becoming the primary technology of choice for generating electricity. At least half of the new generating capacity added in the US over the next twenty years will be combustion turbine systems. The Department of Energy has cosponsored with Siemens Westinghouse, a program to maintain the technology lead in gas turbine systems. The very ambitious eight year program was designed to demonstrate a highly efficient and commercially acceptable power plant, with the ability to fire a wide range of fuels. The main goal of the Advanced Turbine Systems (ATS) Program was to develop ultra-high efficiency, environmentally superior and cost effective competitive gas turbine systems for base load application in utility, independent power producer and industrial markets. Performance targets were focused on natural gas as a fuel and included: System efficiency that exceeds 60% (lower heating value basis); Less than 10 ppmv NO{sub x} emissions without the use of post combustion controls; Busbar electricity that are less than 10% of state of the art systems; Reliability-Availability-Maintainability (RAM) equivalent to current systems; Water consumption minimized to levels consistent with cost and efficiency goals; and Commercial systems by the year 2000. In a parallel effort, the program was to focus on adapting the ATS engine to coal-derived or biomass fuels. In Phase 1 of the ATS Program, preliminary investigators on different gas turbine cycles demonstrated that net plant LHV based efficiency greater than 60% was achievable. In Phase 2 the more promising cycles were evaluated in greater detail and the closed-loop steam-cooled combined cycle was selected for development because it offered the best solution with least risk for achieving the ATS Program goals for plant efficiency, emissions, cost of electricity and RAM. Phase 2 also involved conceptual ATS engine and plant design and technology developments in aerodynamics, sealing, combustion, cooling, materials, coatings and casting development. The market potential for the ATS gas turbine in the 2000-2014 timeframe was assessed for combined cycle, simple cycle and integrated gasification combined cycle, for three engine sizes. The total ATS market potential was forecasted to exceed 93 GW. Phase 3 and Phase 3 Extension involved further technology development, component testing and W501ATS engine detail design. The technology development efforts consisted of ultra low NO{sub x} combustion, catalytic combustion, sealing, heat transfer, advanced coating systems, advanced alloys, single crystal casting development and determining the effect of steam on turbine alloys. Included in this phase was full-load testing of the W501G engine at the McIntosh No. 5 site in Lakeland, Florida.

Gregory Gaul

2004-04-21T23:59:59.000Z

222

Load Alleviation on Wind Turbine Blades using Variable Airfoil Geometry  

E-Print Network [OSTI]

Load Alleviation on Wind Turbine Blades using Variable Airfoil Geometry Peter Bjrn Andersen, Mac Loads, Trailing Edge Flaps, PID control, Signal Noise. 1 Introduction Wind turbine blades are subject to 40% when signal noise is added to the control. Keywords: Wind Turbine, Load Alleviation, Fatigue

223

Jet spoiler arrangement for wind turbine  

DOE Patents [OSTI]

An air jet spoiler arrangement is provided for a Darrieus-type vertical axis wind-powered turbine. Air is drawn into hollow turbine blades through air inlets at the ends thereof and is ejected in the form of air jets through small holes or openings provided along the lengths of the blades. The air jets create flow separation at the surfaces of the turbine blades, thereby inducing stall conditions and reducing the output power. A feedback control unit senses the power output of the turbine and controls the amount of air drawn into the air inlets accordingly.

Cyrus, Jack D. (Corrales, NM); Kadlec, Emil G. (Albuquerque, NM); Klimas, Paul C. (Albuquerque, NM)

1985-01-01T23:59:59.000Z

224

Jet spoiler arrangement for wind turbine  

DOE Patents [OSTI]

An air jet spoiler arrangement is provided for a Darrieus-type vertical axis wind-powered turbine. Air is drawn into hollow turbine blades through air inlets at the end thereof and is ejected in the form of air jets through small holes or openings provided along the lengths of the blades. The air jets create flow separation at the surfaces of the turbine blades, thereby including stall conditions and reducing the output power. A feedback control unit senses the power output of the turbine and controls the amount of air drawn into the air inlets accordingly.

Cyrus, J.D.; Kadlec, E.G.; Klimas, P.C.

1983-09-15T23:59:59.000Z

225

VARIABLE SPEED WIND TURBINE  

E-Print Network [OSTI]

Wind energy is currently the fastest-growing renewable source of energy in India; India is a key market for the wind industry, presenting substantial opportunities for both the international and domestic players. In India the research is carried out on wind energy utilization on big ways.There are still many unsolved challenges in expanding wind power, and there are numerous problems of interest to systems and control researchers. In this paper we study the pitch control mechanism of wind turbine. The pitch control system is one of the most widely used control techniques to regulate the output power of a wind turbine generator. The pitch angle is controlled to keep the generator power at rated power by reducing the angle of the blades. By regulating, the angle of stalling, fast torque changes from the wind will be reutilized. It also describes the design of the pitch controller and discusses the response of the pitch-controlled system to wind velocity variations. The pitch control system is found to have a large output power variation and a large settling time.

Chatinderpal Singh

226

Steam Turbine Cogeneration  

E-Print Network [OSTI]

Steam turbines are widely used in most industrial facilities because steam is readily available and steam turbine is easy to operate and maintain. If designed properly, a steam turbine co-generation (producing heat and power simultaneously) system...

Quach, K.; Robb, A. G.

2008-01-01T23:59:59.000Z

227

Single Rotor Turbine  

DOE Patents [OSTI]

A rotor for use in turbine applications has a centrifugal compressor having axially disposed spaced apart fins forming passages and an axial turbine having hollow turbine blades interleaved with the fins and through which fluid from the centrifugal compressor flows.

Platts, David A. (Los Alamos, NM)

2004-10-26T23:59:59.000Z

228

Fault Diagnosis System for a Multilevel Inverter Using a Neural Network Surin Khomfoi Leon M. Tolbert  

E-Print Network [OSTI]

such as photovoltaic, wind, and fuel cells can be easily interfaced to the multilevel inverter system for a high power multilevel inverter systems are utilized in high power applications, the reliability of the power electronics introduced remedial control strategies soon after failure occurrences; therefore, system reliability

Tolbert, Leon M.

229

Energy 101: Wind Turbines  

SciTech Connect (OSTI)

See how wind turbines generate clean electricity from the power of the wind. Highlighted are the various parts and mechanisms of a modern wind turbine.

None

2011-01-01T23:59:59.000Z

230

Energy 101: Wind Turbines  

ScienceCinema (OSTI)

See how wind turbines generate clean electricity from the power of the wind. Highlighted are the various parts and mechanisms of a modern wind turbine.

None

2013-05-29T23:59:59.000Z

231

SMART POWER TURBINE  

SciTech Connect (OSTI)

Gas turbines are the choice technology for high-performance power generation and are employed in both simple and combined cycle configurations around the world. The Smart Power Turbine (SPT) program has developed new technologies that are needed to further extend the performance and economic attractiveness of gas turbines for power generation. Today's power generation gas turbines control firing temperatures indirectly, by measuring the exhaust gas temperature and then mathematically calculating the peak combustor temperatures. But temperatures in the turbine hot gas path vary a great deal, making it difficult to control firing temperatures precisely enough to achieve optimal performance. Similarly, there is no current way to assess deterioration of turbine hot-gas-path components without shutting down the turbine. Consequently, maintenance and component replacements are often scheduled according to conservative design practices based on historical fleet-averaged data. Since fuel heating values vary with the prevalent natural gas fuel, the inability to measure heating value directly, with sufficient accuracy and timeliness, can lead to maintenance and operational decisions that are less than optimal. GE Global Research Center, under this Smart Power Turbine program, has developed a suite of novel sensors that would measure combustor flame temperature, online fuel lower heating value (LHV), and hot-gas-path component life directly. The feasibility of using the ratio of the integrated intensities of portions of the OH emission band to determine the specific average temperature of a premixed methane or natural-gas-fueled combustion flame was demonstrated. The temperature determined is the temperature of the plasma included in the field of view of the sensor. Two sensor types were investigated: the first used a low-resolution fiber optic spectrometer; the second was a SiC dual photodiode chip. Both methods worked. Sensitivity to flame temperature changes was remarkably high, that is a 1-2.5% change in ratio for an 11.1 C (20 F) change in temperature at flame temperatures between 1482.2 C (2700 F) and 1760 C (3200 F). Sensor ratio calibration was performed using flame temperatures determined by calculations using the amount of unburned oxygen in the exhaust and by the fuel/air ratio of the combustible gas mixture. The agreement between the results of these two methods was excellent. The sensor methods characterized are simple and viable. Experiments are underway to validate the GE Flame Temperature Sensor as a practical tool for use with multiburner gas turbine combustors. The lower heating value (LHV) Fuel Quality Sensor consists of a catalytic film deposited on the surface of a microhotplate. This micromachined design has low heat capacity and thermal conductivity, making it ideal for heating catalysts placed on its surface. Several methods of catalyst deposition were investigated, including micropen deposition and other proprietary methods, which permit precise and repeatable placement of the materials. The use of catalysts on the LHV sensor expands the limits of flammability (LoF) of combustion fuels as compared with conventional flames; an unoptimized LoF of 1-32% for natural gas (NG) in air was demonstrated with the microcombustor, whereas conventionally 4 to 16% is observed. The primary goal of this work was to measure the LHV of NG fuels. The secondary goal was to determine the relative quantities of the various components of NG mixes. This determination was made successfully by using an array of different catalysts operating at different temperatures. The combustion parameters for methane were shown to be dependent on whether Pt or Pd catalysts were used. In this project, significant effort was expended on making the LHV platform more robust by the addition of high-temperature stable materials, such as tantalum, and the use of passivation overcoats to protect the resistive heater/sensor materials from degradation in the combustion environment. Modeling and simulation were used to predict improved sensor designs.

Nirm V. Nirmalan

2003-11-01T23:59:59.000Z

232

Epi-Fluorescence Inverted Microscope (Zeiss,  

E-Print Network [OSTI]

Epi-Fluorescence Inverted Microscope (Zeiss, Observer Z1) April 2013 #12;Start Up cont. · Turn) #12;Using the Microscope cont. · On an inverted microscope samples on a glass slide are usually viewed

Subramanian, Venkat

233

Development of standardized air-blown coal gasifier/gas turbine concepts for future electric power systems. Volume 3, Appendix B: NO{sub x} and alkali vapor control strategies: Final report  

SciTech Connect (OSTI)

CRS Sirrine (CRSS) is evaluating a novel IGCC process in which gases exiting the gasifier are burned in a gas turbine combustion system. The turbine exhaust gas is used to generate additional power in a conventional steam generator. This results in a significant increase in efficiency. However, the IGCC process requires development of novel approaches to control SO{sub 2} and NO{sub x} emissions and alkali vapors which can damage downstream turbine components. Ammonia is produced from the reaction of coal-bound nitrogen with steam in the reducing zone of any fixed bed coal gasifier. This ammonia can be partially oxidized to NO{sub x} when the product gas is oxidized in a gas turbine combustor. Alkali metals vaporize in the high-temperature combustion zone of the gasifier and laser condense on the surface of small char or ash particles or on cooled metal surfaces. It these alkali-coated materials reach the gas turbine combustor, the alkali will revaporize condense on turbine blades and cause rapid high temperature corrosion. Efficiency reduction will result. PSI Technology Company (PSIT) was contracted by CRSS to evaluate and recommend solutions for NO{sub x} emissions and for alkali metals deposition. Various methods for NO{sub x} emission control and the potential process and economic impacts were evaluated. This included estimates of process performance, heat and mass balances around the combustion and heat transfer units and a preliminary economic evaluation. The potential for alkali metal vaporization and condensation at various points in the system was also estimated. Several control processes and evaluated, including an order of magnitude cost for the control process.

Not Available

1990-07-01T23:59:59.000Z

234

Method for detecting gas turbine engine flashback  

DOE Patents [OSTI]

A method for monitoring and controlling a gas turbine, comprises predicting frequencies of combustion dynamics in a combustor using operating conditions of a gas turbine, receiving a signal from a sensor that is indicative of combustion dynamics in the combustor, and detecting a flashback if a frequency of the received signal does not correspond to the predicted frequencies.

Singh, Kapil Kumar; Varatharajan, Balachandar; Kraemer, Gilbert Otto; Yilmaz, Ertan; Lacy, Benjamin Paul

2012-09-04T23:59:59.000Z

235

Leica-Inverted-2 -1-Short instructions Short instructions for the Leica-Inverted-2  

E-Print Network [OSTI]

Leica-Inverted-2 -1- Short instructions Short instructions for the Leica-Inverted-2 Version 230307 off the system Page 8 8. Trouble shooting Page 10 #12;Leica-Inverted-2 -2- Short instructions 1. Laser;Leica-Inverted-2 -3- Short instructions 2. General guidelines 1. Lab rules: This room is a S2 laboratory

Manstein, Dietmar J.

236

David J. Hathaway, IBM EDAInverter Minimization 1 Inverter Minimization -OverviewInverter Minimization -Overview  

E-Print Network [OSTI]

David J. Hathaway, IBM EDAInverter Minimization 1 Inverter Minimization - OverviewInverter network a polarity graph 9 Initially consider only equal cost AND, NAND, OR, and NOR gates 9 Inverters for covering fundamental cycles 9 Considering electrically useful inverters #12;David J. Hathaway, IBM

Ellis-Monaghan, Joanna

237

_ PRICE i 25. od. NETMechanical Aspects of Turbine Blade Cooling COMMUNICATED BY THE DEPUTY CONTROLLER AIRCRAFT (RESEARCH AND [V~INISTRY OF AVIATION  

E-Print Network [OSTI]

Part I.--Description of an Experimental High-Temperature Turbine and Associated Test Rig (Cooled Turbine No.!26) Summary. By N. E. WALDREN and J. A. FLINT Part I of this report describes an experimental, cooled turbine, designed and built for research into problems associated with the operation of turbines at very high gas temperatures, in particular, the problem of turbine blade cooling. The turbine structure and the associated test rig have been designed to permit testing of turbine blades over a wide range of turbine entry gas temperature from 900K to 1600K and entry gas pressure from ~ to 5 atmospheres giving a wide range of gas-flow Reynolds numbers to the blades. A further aim of the design has been to achieve rapid access to blades under test and to allow the testing of a moderately wide variety of both blades and cooling systems with relatively minor alteration to the turbine or test rig. Initial proving tests have been made to observe the mechanical behaviour of the turbine and test rig and to establish optimum coolant quantities required to cool the turbine structure.

Part I; N. E. Waldren; J. A. Flint; J. F. Barnes; J. E. Northwood; D. E. Fray

238

On Optimal Inverters Department of Computer Science  

E-Print Network [OSTI]

On Optimal Inverters Yijia Chen Department of Computer Science Shanghai Jiaotong University yijia.flum@math.uni­freiburg.de Abstract Leonid Levin showed that every algorithm computing a function has an optimal inverter. Recently. An inverter I of F is an algorithm that for all y in the range of F computes a preimage I(y) of y, i.e., F

Chen, Yijia

239

AN "AC INDUCTOR" BASED GRID CONNECTED INVERTER  

E-Print Network [OSTI]

AN "AC INDUCTOR" BASED GRID CONNECTED INVERTER Ilya Zeltser, Student Member, IEEE and Sam Ben proposes a soft switched Output Current Sourcing (OCS) grid connected inverter that applies a high sourcing inverters where the small disturbance at the line voltage may lead to current run away

240

Invertibility of random matrices M. Rudelson  

E-Print Network [OSTI]

Invertibility of random matrices M. Rudelson We will discuss several recent developments related to invertibility and spectral properties of large random matrices. Consider an n ? n matrix, whose values are independent identically distributed random variables. The invertibility questions can be roughly divided

Weinberger, Hans

Note: This page contains sample records for the topic "turbine controllers inverters" 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

On Optimal Inverters Department of Computer Science  

E-Print Network [OSTI]

On Optimal Inverters Yijia Chen Department of Computer Science Shanghai Jiaotong University yijia.flum@math.uni-freiburg.de Abstract Leonid Levin showed that every algorithm computing a function has an optimal inverter. Recently. An inverter I of F is an algorithm that for all y in the range of F computes a preimage I(y) of y, i.e., F

Chen, Yijia

242

Joint Inverted Indexing Kaiming He2  

E-Print Network [OSTI]

Joint Inverted Indexing Yan Xia1 Kaiming He2 Fang Wen2 Jian Sun2 1 University of Science and Technology of China 2 Microsoft Research Asia Abstract Inverted indexing is a popular non-exhaustive solution to large scale search. An inverted file is built by a quantizer such as k-means or a tree structure. It has

Bernstein, Phil

243

Wind turbine  

SciTech Connect (OSTI)

The improvement in a wind turbine comprises providing a tower with a freely liftable mount and adapting a nacelle which is fitted with a propeller windwheel consisting of a plurality of rotor blades and provided therein with means for conversion of wind energy to be shifted onto said mount attached to the tower. In case of a violent wind storm, the nacelle can be lowered down to the ground to protect the rotor blades from breakage due to the force of the wind. Required maintenance and inspection of the nacelle and replacement of rotor blades can be safely carried out on the ground.

Abe, M.

1982-01-19T23:59:59.000Z

244

36 AUGUST | 2011 EnhancEd TurbinE  

E-Print Network [OSTI]

36 AUGUST | 2011 EnhancEd TurbinE PErformancE moniToring comPonEnTs of wind TurbinEs are affected by asymmetric loads, variable wind speeds, and se- vere weather conditions which cause wind turbines to change their states. A typical wind turbine under- goes various states during its daily operations. The wind turbine

Kusiak, Andrew

245

PowerJet Wind Turbine Project  

SciTech Connect (OSTI)

PROJECT OBJECTIVE The PowerJet wind turbine overcomes problems characteristic of the small wind turbines that are on the market today by providing reliable output at a wide range of wind speeds, durability, silent operation at all wind speeds, and bird-safe operation. Prime Energyâ??s objective for this project was to design and integrate a generator with an electrical controller and mechanical controls to maximize the generation of electricity by its wind turbine. The scope of this project was to design, construct and test a mechanical back plate to control rotational speed in high winds, and an electronic controller to maximize power output and to assist the base plate in controlling rotational speed in high winds. The test model will continue to operate beyond the time frame of the project, with the ultimate goal of manufacturing and marketing the PowerJet worldwide. Increased Understanding of Electronic & Mechanical Controls Integrated With Electricity Generator The PowerJet back plate begins to open as wind speed exceeds 13.5 mps. The pressure inside the turbine and the turbine rotational speed are held constant. Once the back plate has fully opened at approximately 29 mps, the controller begins pulsing back to the generator to limit the rotational speed of the turbine. At a wind speed in excess of 29 mps, the controller shorts the generator and brings the turbine to a complete stop. As the wind speed subsides, the controller releases the turbine and it resumes producing electricity. Data collection and instrumentation problems prevented identification of the exact speeds at which these events occur. However, the turbine, controller and generator survived winds in excess of 36 mps, confirming that the two over-speed controls accomplished their purpose. Technical Effectiveness & Economic Feasibility Maximum Electrical Output The output of electricity is maximized by the integration of an electronic controller and mechanical over-speed controls designed and tested during the course of this project. The output exceeds that of the PowerJetâ??s 3-bladed counterparts (see Appendix). Durability All components of the PowerJet turbine assemblyâ??including the electronic and mechanical controls designed, manufactured and field tested during the course of this projectâ??proved to be durable through severe weather conditions, with constant operation and no interruption in energy production. Low Cost Materials for the turbine, generator, tower, charge controllers and ancillary parts are available at reasonable prices. Fabrication of these parts is also readily available worldwide. The cost of assembling and installing the turbine is reduced because it has fewer parts and requires less labor to manufacture and assemble, making it competitively priced compared with turbines of similar output manufactured in the U.S. and Europe. The electronic controller is the unique part to be included in the turbine package. The controllers can be manufactured in reasonably-sized production runs to keep the cost below $250 each. The data logger and 24 sensors are for research only and will be unnecessary for the commercial product. Benefit To Public The PowerJet wind-electric system is designed for distributed wind generation in 3 and 4 class winds. This wind turbine meets DOEâ??s requirements for a quiet, durable, bird-safe turbine that eventually can be deployed as a grid-connected generator in urban and suburban settings. Results As described more fully below and illustrated in the Appendices, the goals and objectives outlined in 2060 SOPO were fully met. Electronic and mechanical controls were successfully designed, manufactured and integrated with the generator. The turbine, tower, controllers and generators operated without incident throughout the test period, surviving severe winter and summer weather conditions such as extreme temperatures, ice and sustained high winds. The electronic controls were contained in weather-proof electrical boxes and the elec

Bartlett, Raymond J

2008-11-30T23:59:59.000Z

246

Optimal Dispatch of Photovoltaic Inverters in Residential Distribution Systems  

E-Print Network [OSTI]

, reactive power generation/consumption based on monitoring local electrical quantities has been recog- nized method for determining the active- and reactive-power set points for PV inverters in residential systems as a viable option to effect voltage regulation [4], [8]­[12]. However, such reactive power control (RPC

Giannakis, Georgios

247

Fault Tolerance on Interleaved inverter with Magnetic couplers  

E-Print Network [OSTI]

Fault Tolerance on Interleaved inverter with Magnetic couplers K.Guépratte, D.Frey, P-O.Jeannin, H Electrical Engineering (G2Elab), Thales Systemes Aeroportes Abstract- The paper focuses on a new control strategy for improving the availability of power electronic converters based on interleaved structures

Paris-Sud XI, Université de

248

Thermal Study of Inverter Components: Preprint  

SciTech Connect (OSTI)

Thermal histories of inverter components were collected from operating inverters from several manufacturers and three locations. The data were analyzed to determine thermal profiles, the dependence on local conditions, and to assess the effect on inverter reliability. Inverter temperatures were shown to increase with the power dissipation of the inverters, follow diurnal and annual cycles, and have a dependence on wind speed. An accumulated damage model was applied to the temperature profiles and an example of using these data to predict reliability was explored.

Sorensen, N. R.; Thomas, E. V.; Quintana, M. A.; Barkaszi, S.; Rosenthal, A.; Zhang, Z.; Kurtz, S.

2012-06-01T23:59:59.000Z

249

IEEE IAS 1998 Annual Meeting, St. Louis, Missouri, October 10-15, 1998, pp. 1424-1431. Novel Multilevel Inverter Carrier-Based PWM Methods  

E-Print Network [OSTI]

Multilevel Inverter Carrier-Based PWM Methods Leon M. Tolbert Thomas G. Habetler Oak Ridge National inverter topology has brought forth various pulse width modulation (PWM) schemes as a means to control the switching of the active devices in each of the multiple voltage levels in the inverter. An analysis of how

Tolbert, Leon M.

250

Wind Turbine Pitch Optimization Benjamin Biegel Morten Juelsgaard Matt Kraning Stephen Boyd Jakob Stoustrup  

E-Print Network [OSTI]

Wind Turbine Pitch Optimization Benjamin Biegel Morten Juelsgaard Matt Kraning Stephen Boyd Jakob-controlled wind tur- bine. When placed in a wind field, the turbine experiences several mechanical loads, which measurements, with no knowledge of the wind field or wind turbine model. I. INTRODUCTION Wind turbines

251

Foam Cleaning of Steam Turbines  

E-Print Network [OSTI]

The efficiency and power output of a steam turbine can be dramatically reduced when deposits form on the turbine blades. Disassembly and mechanical cleaning of the turbine is very time consuming and costly. Deposits can be removed from the turbine...

Foster, C.; Curtis, G.; Horvath, J. W.

252

Wind Turbines Benefit Crops  

ScienceCinema (OSTI)

Ames Laboratory associate scientist Gene Takle talks about research into the effect of wind turbines on nearby crops. Preliminary results show the turbines may have a positive effect by cooling and drying the crops and assisting with carbon dioxide uptake.

Takle, Gene

2013-03-01T23:59:59.000Z

253

Hybrid Multilevel Inverter with Single DC Haiwen Liu1  

E-Print Network [OSTI]

Hybrid Multilevel Inverter with Single DC Source Haiwen Liu1 , Leon M. Tolbert1, 2 , Burak Ozpineci Knoxville, TN 37932 3. Parker-Hannifin Corp. Olive Branch, MI 38654 Abstract- A hybrid multilevel inverter inverter (one leg for each phase) and H-bridge in series with each inverter leg. The inverter can be used

Tolbert, Leon M.

254

High voltage power supply with modular series resonant inverters  

DOE Patents [OSTI]

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

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

1995-01-01T23:59:59.000Z

255

High voltage power supply with modular series resonant inverters  

DOE Patents [OSTI]

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

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

1995-07-18T23:59:59.000Z

256

Understanding Trends in Wind Turbine Prices Over the Past Decade  

SciTech Connect (OSTI)

Taking a bottom-up approach, this report examines seven primary drivers of wind turbine prices in the United States, with the goal of estimating the degree to which each contributed to the doubling in turbine prices from 2002 through 2008, as well as the subsequent decline in prices through 2010 (our analysis does not extend into 2011 because several of these drivers are best gauged on a full-year basis due to seasonality issues). The first four of these drivers can be considered, at least to some degree, endogenous influences i.e., those that are largely within the control of the wind industry and include changes in: 1) Labor costs, which have historically risen during times of tight turbine supply; 2) Warranty provisions, which reflect technology performance and reliability, and are most often capitalized in turbine prices; 3) Turbine manufacturer profitability, which can impact turbine prices independently of costs; and 4) Turbine design, which for the purpose of this analysis is principally manifested through increased turbine size. The other three drivers analyzed in this study can be considered exogenous influences, in that they can impact wind turbine costs but fall mostly outside of the direct control of the wind industry. These exogenous drivers include changes in: 5) Raw materials prices, which affect the cost of inputs to the manufacturing process; 6) Energy prices, which impact the cost of manufacturing and transporting turbines; and 7) Foreign exchange rates, which can impact the dollar amount paid for turbines and components imported into the United States.

Bolinger, Mark; Wiser, Ryan

2011-10-26T23:59:59.000Z

257

Sliding vane geometry turbines  

DOE Patents [OSTI]

Various systems and methods are described for a variable geometry turbine. In one example, a turbine nozzle comprises a central axis and a nozzle vane. The nozzle vane includes a stationary vane and a sliding vane. The sliding vane is positioned to slide in a direction substantially tangent to an inner circumference of the turbine nozzle and in contact with the stationary vane.

Sun, Harold Huimin; Zhang, Jizhong; Hu, Liangjun; Hanna, Dave R

2014-12-30T23:59:59.000Z

258

Combined Cycle Combustion Turbines  

E-Print Network [OSTI]

Combined Cycle Combustion Turbines Steven Simmons February 27 2014 1 #12;CCCT Today's Discussion 1 Meeting Pricing of 4 advanced units using information from Gas Turbine World Other cost estimates from E E3 EIA Gas Turbine World California Energy Commission Date 2010 Oct 2012, Dec 2013 Apr 2013 2013 Apr

259

Hardware Development of a Laboratory-Scale Microgrid Phase 1--Single Inverter in Island Mode Operation: Base Year Report, December 2000 -- November 2001  

SciTech Connect (OSTI)

This report summarizes the activities of the first year of a three-year project to develop control software for micro-source distributed generation systems. The focus of this phase was on internal energy storage requirements, the modification of an off-the-shelf motor drive system inverter to supply utility-grade ac power, and a single inverter system operating in island mode. The report provides a methodology for determining battery energy storage requirements, a method for converting a motor drive inverter into a utility-grade inverter, and typical characteristics and test results of using such an inverter in a complex load environment.

Venkataramanan, G.; Illindala, M. S.; Houle, C.; Lasseter, R. H.

2002-11-01T23:59:59.000Z

260

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

DOE Patents [OSTI]

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

Pitel, I.J.

1987-02-03T23:59:59.000Z

Note: This page contains sample records for the topic "turbine controllers inverters" 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

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

DOE Patents [OSTI]

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

Pitel, Ira J. (Whippany, NJ)

1987-02-03T23:59:59.000Z

262

The inverter in a hybrid or fully  

E-Print Network [OSTI]

The inverter in a hybrid or fully electric vehicle, such as the Toyota Prius, supplies power from the batteries to the motor. Inverters used in this application are currently limited by their power new material devices under real operating conditions. A project with TRW and others is investigating

Davies, Christopher

263

Inverted faces are (eventually) processed holistically Jennifer J. Richler  

E-Print Network [OSTI]

Inverted faces are (eventually) processed holistically Jennifer J. Richler , Michael L. Mack whether processing differences between upright and inverted faces are qualitative or quantitative. We present two experiments comparing holistic processing of upright and inverted faces within the composite

Palmeri, Thomas

264

Invertible extensions of continuous maps Real symmetric functions  

E-Print Network [OSTI]

Invertible extensions of continuous maps Real symmetric functions Covering dimension Bass and topological stable rank Real symmetric extensions of invertible tuples of multivariable continuous functions;Invertible extensions of continuous maps Real symmetric functions Covering dimension Bass and topological

Mortini, Raymond

265

A new technique to reject dc-link voltage ripple in PWM inverters  

E-Print Network [OSTI]

to acknowledge the support of my husband and parents. TA. BLE OF CONTENTS CHAPTER I INTRODUCTION Page I. l Inverter Power Supplies 1. 2 Output Voltage Control 1. 2. 1 Control Of Voltage Supplied To The Inverter I. 2. 2 Control Of Voltage Within... and output of Stage 3 78 34 Exact solution of the switching angle trajectories for harmonic elimination with voltage control (M). 85 CHAPTER I INTRODUCTION Finding ways to control the flow of electricity has been a. goal of inventors and scientists...

Shireen, Wajiha

1990-01-01T23:59:59.000Z

266

Integration of Novel Flux Coupling Motor and Current Source Inverter...  

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

Current Source Inverters for HEVs and FCVs Vehicle Technologies Office Merit Review 2014: Wireless Charging Integration of Novel Flux Coupling Motor and Current Source Inverter...

267

High-Temperature, Air-Cooled Traction Drive Inverter Packaging...  

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

High-Temperature, Air-Cooled Traction Drive Inverter Packaging High-Temperature, Air-Cooled Traction Drive Inverter Packaging 2010 DOE Vehicle Technologies and Hydrogen Programs...

268

Optically Isolated HVIGBT Based MW Cascade Inverter Building...  

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

Capacity Power ConverterInverter Competitive Advantages Only One Other >100 KW Heat Pipe Inverter - GE Innovation Series Converter - Non-Optical, Lower Power Capacity...

269

Integration of Novel Flux Coupling Motor and Current Source Inverter  

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

To integrate a non permanent magnet (PM) electric machine and a current source inverter (CSI) * minimizing capacitors in inverters * eliminating rare earth materials used in...

270

Advanced Soft Switching Inverter for Reducing Switching and Power...  

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

lai.pdf More Documents & Publications Advanced Soft Switching Inverter for Reducing Switching and Power Losses Advanced Soft Switching Inverter for Reducing Switching and Power...

271

28 IEEE TRANSACTIONS ON SUSTAINABLE ENERGY, VOL. 2, NO. 1, JANUARY 2011 Adaptive Control of a Wind Turbine With Data  

E-Print Network [OSTI]

28 IEEE TRANSACTIONS ON SUSTAINABLE ENERGY, VOL. 2, NO. 1, JANUARY 2011 Adaptive Control of a Wind of the most viable sources of renewable energy, wind power is undergoing rapid expansion. Although wind energy research has expanded in scope to cover domains such as, for example, wind energy conversion [1], [2

Kusiak, Andrew

272

Inverted catenoids, curvature singularities and tethered membranes  

E-Print Network [OSTI]

If a catenoid is inverted in any interior point, a deflated compact geometry is obtained which touches at two points (its poles). The catenoid is a minimal surface and, as such, is an equilibrium shape of a symmetric fluid membrane. The conformal symmetry of the Hamiltonian implies that inverted minimal surfaces are also equilibrium shapes. However, they exhibit curvature singularities at their poles. These singularities are associated with external forces pulling the poles together. Unlike the catenoid which is free of stress, there will be stress within the inverted shapes. If the surface area is fixed, reducing the external force induces a transition from a discocyte to a cup-shaped stomatocyte.

Pavel Castro-Villarreal; Jemal Guven

2007-02-14T23:59:59.000Z

273

Commercialization of a 2.5kW Utility Interactive Inverter for Distributed Generation  

SciTech Connect (OSTI)

Through this project, Advanced Energy Conversion (AEC) has developed, tested, refined and is preparing to commercialize a 2.5kW utility-interactive inverter system for distributed generation. The inverter technology embodies zero-voltage switching technology that will ultimately yield a system that is smaller, less expensive and more efficient than existing commercial technologies. This program has focused on commercial success through careful synthesis of technology, market-focus and business development. AEC was the primary participant. AEC is utilizing contract manufacturers in the early stages of production, allowing its technical staff to focus on quality control issues and product enhancements. The objective of this project was to bring the AEC inverter technology from its current pre-production state to a commercial product. Federal funds have been used to build and test production-intent inverters, support the implementation of the commercialization plan and bring the product to the point of UL certification.

Torrey, David A.

2006-05-26T23:59:59.000Z

274

Improving steam turbine efficiency  

SciTech Connect (OSTI)

This paper describes the condition of a significant number of fossil steam turbines operating in the United States and the maintenance practices used to improve their performance. Through the use of steam path audits conducted by the authors` company and by several utilities, a large data base of information on turbine heat rate, casing efficiency, and maintenance practices is available to help the power generation industry understand how different maintenance practices and steam path damage impact turbine performance. The data base reveals that turbine cycle heat rate is typically 5.23% poorer than design just prior to major outages. The degraded condition of steam turbines presents an opportunity for utilities to improve heat rate and reduce emissions without increasing fuel costs. The paper describes what losses typically contribute to the 5.23% heat rate degradation and how utilities can recover steam turbine performance through maintenance actions aimed at improving steam path efficiency.

Cioffi, D.H.; Mitchell, D.R.; Whitecar, S.C. [Encotech, Inc., Schenectady, NY (United States)

1995-06-01T23:59:59.000Z

275

Predicting Steam Turbine Performance  

E-Print Network [OSTI]

," PREDICTING STEAM TURBINE PERFORMANCE James T. Harriz, EIT Waterland, Viar & Associates, Inc. Wilmington, Delaware ABSTRACT Tracking the performance of extraction, back pressure and condensing steam turbines is a crucial part... energy) and test data are presented. Techniques for deriving efficiency curves from each source are described. These techniques can be applied directly to any steam turbine reliability study effort. INTRODUCTION As the cost of energy resources...

Harriz, J. T.

276

Direct drive wind turbine  

DOE Patents [OSTI]

A wind turbine is provided that minimizes the size of the drive train and nacelle while maintaining the power electronics and transformer at the top of the tower. The turbine includes a direct drive generator having an integrated disk brake positioned radially inside the stator while minimizing the potential for contamination. The turbine further includes a means for mounting a transformer below the nacelle within the tower.

Bywaters, Garrett; Danforth, William; Bevington, Christopher; Jesse, Stowell; Costin, Daniel

2006-10-10T23:59:59.000Z

277

Direct drive wind turbine  

DOE Patents [OSTI]

A wind turbine is provided that minimizes the size of the drive train and nacelle while maintaining the power electronics and transformer at the top of the tower. The turbine includes a direct drive generator having an integrated disk brake positioned radially inside the stator while minimizing the potential for contamination. The turbine further includes a means for mounting a transformer below the nacelle within the tower.

Bywaters, Garrett; Danforth, William; Bevington, Christopher; Stowell, Jesse; Costin, Daniel

2006-07-11T23:59:59.000Z

278

Direct drive wind turbine  

DOE Patents [OSTI]

A wind turbine is provided that minimizes the size of the drive train and nacelle while maintaining the power electronics and transformer at the top of the tower. The turbine includes a direct drive generator having an integrated disk brake positioned radially inside the stator while minimizing the potential for contamination. The turbine further includes a means for mounting a transformer below the nacelle within the tower.

Bywaters, Garrett Lee; Danforth, William; Bevington, Christopher; Stowell, Jesse; Costin, Daniel

2006-09-19T23:59:59.000Z

279

Direct drive wind turbine  

DOE Patents [OSTI]

A wind turbine is provided that minimizes the size of the drive train and nacelle while maintaining the power electronics and transformer at the top of the tower. The turbine includes a direct drive generator having an integrated disk brake positioned radially inside the stator while minimizing the potential for contamination. The turbine further includes a means for mounting a transformer below the nacelle within the tower.

Bywaters, Garrett; Danforth, William; Bevington, Christopher; Jesse, Stowell; Costin, Daniel

2007-02-27T23:59:59.000Z

280

Hermetic turbine generator  

DOE Patents [OSTI]

A Rankine cycle turbine drives an electric generator and a feed pump, all on a single shaft, and all enclosed within a hermetically sealed case. The shaft is vertically oriented with the turbine exhaust directed downward and the shaft is supported on hydrodynamic fluid film bearings using the process fluid as lubricant and coolant. The selection of process fluid, type of turbine, operating speed, system power rating, and cycle state points are uniquely coordinated to achieve high turbine efficiency at the temperature levels imposed by the recovery of waste heat from the more prevalent industrial processes.

Meacher, John S. (Ballston Lake, NY); Ruscitto, David E. (Ballston Spa, NY)

1982-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "turbine controllers inverters" 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

Economical Condensing Turbines?  

E-Print Network [OSTI]

an engineer decide when to conduct an in depth study of the economics either in the company or outside utilizing professional engineers who are experts in this type of project. Condensing steam turbines may not be economical when the fuel is purchased...Economical Condensing Turbines? by J.E.Dean, P.E. Steam turbines have long been used at utilities and in industry to generate power. There are three basic types of steam turbines: condensing, letdown 1 and extraction/condensing. ? Letdown...

Dean, J. E.

282

Barstow Wind Turbine Project  

Broader source: Energy.gov [DOE]

Presentation covers the Barstow Wind Turbine project for the Federal Utility Partnership Working Group (FUPWG) meeting, held on November 18-19, 2009.

283

Rampressor Turbine Design  

SciTech Connect (OSTI)

The design of a unique gas turbine engine is presented. The first Rampressor Turbine engine rig will be a configuration where the Rampressor rotor is integrated into an existing industrial gas turbine engine. The Rampressor rotor compresses air which is burned in a traditional stationary combustion system in order to increase the enthalpy of the compressed air. The combustion products are then expanded through a conventional gas turbine which provides both compressor and electrical power. This in turn produces shaft torque, which drives a generator to provide electricity. The design and the associated design process of such an engine are discussed in this report.

Ramgen Power Systems

2003-09-30T23:59:59.000Z

284

Single-electron inverter C. P. Heij,a)  

E-Print Network [OSTI]

Single-electron inverter C. P. Heij,a) P. Hadley, and J. E. Mooij Applied Physics and DIMES, Delft for publication 8 December 2000 A single-electron inverter was fabricated that switches from a high output of the inverter, the two single-electron transistors that make up the inverter must exhibit voltage gain. Voltage

285

Analysis and test results for a two-bladed, passive cycle pitch, horizontal-axis wind turbine in free and controlled yaw  

SciTech Connect (OSTI)

This report surveys the analysis and tests performed at Washington University in St. Louis, Missouri, on a horizontal-axis, two-laded wind turbine with teeter hub. The introduction is a brief account of results obtained during the 5-year period ending December 1985. The wind tunnel model and the test turbine (7.6 m [25 ft.] in diameter) at Washington University`s Tyson Research Center had a 67{degree} delta-three angle of the teeter axis. The introduction explains why this configuration was selected and named the passive cycle pitch (PCP) wind turbine. Through the analysis was not limited to the PCP rotor, all tests, including those done from 1986 to 1994, wee conducted with the same teetered wind rotor. The blades are rather stiff and have only a small elastic coning angle and no precone.

Holenemser, K.H. [Washington Univ., St. Louis, MO (United States)

1995-10-01T23:59:59.000Z

286

Laboratory implementation of variable-speed wind turbine generation  

SciTech Connect (OSTI)

To improve the performance of wind turbines, various control schemes such as variable speed operation have been proposed. Testing of these control algorithms on a full scale system is very expensive. To test these systems simulation, we developed programs and small scale laboratory experiments. We used this system to verify a control method that attempts to keep the turbine operating at its peak power coefficient. Both the simulations and the experiments verified the principle of operation of this control scheme.

Zinger, D.S. [Northern Illinois University, DeKalb, IL (United States)] [Northern Illinois University, DeKalb, IL (United States); Miller, A.A. [Univ. of Idaho, Moscow, ID (United States)] [Univ. of Idaho, Moscow, ID (United States); Muljadi, E.; Butterfield, C.P.; Robinson, M.C. [National Renewable Energy Lab., Golden, CO (United States)] [National Renewable Energy Lab., Golden, CO (United States)

1996-07-01T23:59:59.000Z

287

NWTC Controllable Grid Interface (Fact Sheet)  

SciTech Connect (OSTI)

NREL's Controllable Grid Interface tests wind turbines off-line from the grid, verifies compliance with standards, and provides grid operators with the performance information they need for a faction of the time and cost it would take to test the turbine in the field. To understand the behavior of wind turbines during grid disturbances, manufacturers and utility grid operators need to perform a series of tests and accurate transient simulation studies. The latest edition of the IEC 61400-21 standard describes methods for such tests that include low voltage ride-through (LVRT), active power set-point control, ramp rate limitations, and reactive power capability tests. The IEC methods are being widely adopted on both national and international levels by wind turbine manufacturers, certification authorities, and utilities. Utility operators also need to estimate how much power wind turbines might be able provide to help regulate grid frequency during situations when they need additional energy quickly, and after design modifications or changes are made to control software, manufacturers may be required to retest their turbines. But testing wind turbines in the field can be a lengthy and expensive process often requiring manufacturers and utility operators to send equipment and personnel to remote locations for long periods of time. NREL's National Wind Technology Center (NWTC) has developed a new Controllable Grid Interface (CGI) test system that can significantly reduce the time and cost required to conduct these tests. The CGI is first test facility in the United States that has fault simulation capabilities and allows manufacturers and system operators to conduct the tests required for certification in a controlled laboratory environment. It is the only system in the world that is fully integrated with two dynamometers and has the capacity to extend that integration to turbines in the field and to a matrix of electronic and mechanical storage devices, all of which are located within close proximity on the same site. NREL's 7.5 MVA CGI tests wind turbines off-line from the grid, verifies compliance with standards, and provides grid operators with the performance information they need for a fraction of the time and cost it would take to test the turbine in the field. The system combines hardware and real-time control software and is designed to operate with the NWTC's 2.5-MW dynamometer as well as the center's new 5-MW dynamometer test facilities. It is designed to work with four types of wind turbines, photovoltaic systems, and energy storage inverters. Results from the dynamometer tests can also be used to fine tune and validate the dynamic models used in integration studies and help industry improve turbine performance and develop test standards for renewable technologies and energy storage.

Not Available

2012-02-01T23:59:59.000Z

288

Turbine bearings and rotor dynamics workshop: proceedings  

SciTech Connect (OSTI)

An EPRI workshop to address turbine bearing reliability improvement and rotor dynamics was co-hosted by Detroit Edison in Dearborn, Michigan on September 8-10, 1982. The 136 attendees represented a broad spectrum of US utilities, equipment manufacturers, and consultants, as well as representatives from England, Japan, and Switzerland. These proceedings contain the text of the formal presentations as well as summaries of the working group sessions which were devoted to topics of particular interest to the workshop participants. Formal presentations were organized under the following general session titles: utility experience and advancements in turbine bearing and lubrication systems; recent advancements in turbine bearing and lubrication systems; utility experience and advancements in turbine-generator rotor dynamics; and recent advancements in turbine-generator rotor dynamics. In addition to the technical presentations, working group sessions were held on selected topics relevant to turbine bearing reliability improvement and rotor dynamics. These groups provided a forum for engineers to exchange ideas and information in a less formal environment. The discussions provided attendees with an opportunity to discuss key issues in more detail and address subjects not covered in the formal presentations. The subjects of these working groups were: rotor dynamic analysis and problem solving; vibration signature analysis and field balancing; oil contamination monitoring and control; and operation and maintenance practices. Individual papers have been entered individually into EDB and ERA.

Brown, R.G.; Quilliam, J.F. (eds.)

1985-06-01T23:59:59.000Z

289

Annual Report: Turbines (30 September 2012)  

SciTech Connect (OSTI)

The FY12 NETL-RUA Turbine Thermal Management effort supported the Department of Energy (DOE) Hydrogen Turbine Program through conduct of novel, fundamental, basic, and applied research in the areas of aerothermal heat transfer, coatings development, and secondary flow control. This research project utilized the extensive expertise and facilities readily available at NETL and the participating universities. The research approach includes explorative studies based on scaled models and prototype coupon tests conducted under realistic high-temperature, pressurized, turbine operating conditions. This research is expected to render measurable outcomes that will meet DOE advanced turbine development goals of a 3- to 5-point increase in power island efficiency and a 30 percent power increase above the hydrogen-fired combined cycle baseline. In addition, knowledge gained from this project will further advance the aerothermal cooling and TBC technologies in the general turbine community. This project has been structured to address ? Development and design of aerothermal and materials concepts in FY12-13. ? Design and manufacturing of these advanced concepts in FY13. ? Bench-scale/proof-of-concept testing of these concepts in FY13-14 and beyond. The Turbine Thermal Management project consists of four tasks that focus on a critical technology development in the areas of aerothermal and heat transfer, coatings and materials development, design integration and testing, and a secondary flow rotating rig.

Alvin, Mary Anne [NETL] [NETL; Richards, George [NETL] [NETL

2012-09-30T23:59:59.000Z

290

Turbine disc sealing assembly  

DOE Patents [OSTI]

A disc seal assembly for use in a turbine engine. The disc seal assembly includes a plurality of outwardly extending sealing flange members that define a plurality of fluid pockets. The sealing flange members define a labyrinth flow path therebetween to limit leakage between a hot gas path and a disc cavity in the turbine engine.

Diakunchak, Ihor S.

2013-03-05T23:59:59.000Z

291

Gas turbine diagnostic system  

E-Print Network [OSTI]

In the given article the methods of parametric diagnostics of gas turbine based on fuzzy logic is proposed. The diagnostic map of interconnection between some parts of turbine and changes of corresponding parameters has been developed. Also we have created model to define the efficiency of the compressor using fuzzy logic algorithms.

Talgat, Shuvatov

2011-01-01T23:59:59.000Z

292

Single rotor turbine engine  

DOE Patents [OSTI]

There has been invented a turbine engine with a single rotor which cools the engine, functions as a radial compressor, pushes air through the engine to the ignition point, and acts as an axial turbine for powering the compressor. The invention engine is designed to use a simple scheme of conventional passage shapes to provide both a radial and axial flow pattern through the single rotor, thereby allowing the radial intake air flow to cool the turbine blades and turbine exhaust gases in an axial flow to be used for energy transfer. In an alternative embodiment, an electric generator is incorporated in the engine to specifically adapt the invention for power generation. Magnets are embedded in the exhaust face of the single rotor proximate to a ring of stationary magnetic cores with windings to provide for the generation of electricity. In this alternative embodiment, the turbine is a radial inflow turbine rather than an axial turbine as used in the first embodiment. Radial inflow passages of conventional design are interleaved with radial compressor passages to allow the intake air to cool the turbine blades.

Platts, David A. (Los Alamos, NM)

2002-01-01T23:59:59.000Z

293

Effect of turbine-operating regime and adjustment of automated control system on stability and critical area of surge tanks at HPP  

SciTech Connect (OSTI)

Materials of the works of several authors who have investigated the effect of turbine-operating regime on the stability of HPP with surge tanks are presented. Anumber of new results are obtained. Analytical relationships that can be used in stability calculations for a number of coefficients are compared with a large amount of actual data.

Murav'ev, O. A. [Moscow State Civil-Engineering University (Russian Federation)

2011-05-15T23:59:59.000Z

294

Robust 1550-nm single-frequency all-fiber ns-pulsed fiber amplifier for wind-turbine predictive control by wind lidar  

E-Print Network [OSTI]

Oldenburg, Germany ABSTRACT Scaling of the power yield of offshore wind farms relies on the capacity powers [1]. To reach the ambitious and politically motivated aims of Multi-GW offshore wind farms belongs to this category. Clustered in wind farms, today's wind turbines produce Megawatt-level output

Oldenburg, Carl von Ossietzky Universität

295

Ceramic turbine nozzle  

DOE Patents [OSTI]

A turbine nozzle and shroud assembly having a preestablished rate of thermal expansion is positioned in a gas turbine engine and being attached to conventional metallic components. The metallic components having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine nozzle vane assembly. The turbine nozzle vane assembly includes a plurality of segmented vane defining a first vane segment and a second vane segment. Each of the first and second vane segments having a vertical portion. Each of the first vane segments and the second vane segments being positioned in functional relationship one to another within a recess formed within an outer shroud and an inner shroud. The turbine nozzle and shroud assembly provides an economical, reliable and effective ceramic component having a preestablished rate of thermal expansion being less than the preestablished rate of thermal expansion of the other component.

Shaffer, James E. (Maitland, FL); Norton, Paul F. (San Diego, CA)

1996-01-01T23:59:59.000Z

296

Ceramic turbine nozzle  

DOE Patents [OSTI]

A turbine nozzle and shroud assembly having a preestablished rate of thermal expansion is positioned in a gas turbine engine and being attached to conventional metallic components. The metallic components have a preestablished rate of thermal expansion greater than the preestablished rate of thermal expansion of the turbine nozzle vane assembly. The turbine nozzle vane assembly includes a plurality of segmented vane defining a first vane segment and a second vane segment, each of the first and second vane segments having a vertical portion, and each of the first vane segments and the second vane segments being positioned in functional relationship one to another within a recess formed within an outer shroud and an inner shroud. The turbine nozzle and shroud assembly provides an economical, reliable and effective ceramic component having a preestablished rate of thermal expansion being less than the preestablished rate of thermal expansion of the other component. 4 figs.

Shaffer, J.E.; Norton, P.F.

1996-12-17T23:59:59.000Z

297

Ceramic Cerami Turbine Nozzle  

DOE Patents [OSTI]

A turbine nozzle vane assembly having a preestablished rate of thermal expansion is positioned in a gas turbine engine and being attached to conventional metallic components. The metallic components having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine nozzle vane assembly. The turbine nozzle vane assembly includes an outer shroud and an inner shroud having a plurality of horizontally segmented vanes therebetween being positioned by a connecting member positioning segmented vanes in functional relationship one to another. The turbine nozzle vane assembly provides an economical, reliable and effective ceramic component having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the other component.

Boyd, Gary L. (Alpine, CA)

1997-04-01T23:59:59.000Z

298

FRICTION AND THE INVERTED PENDULUM STABILIZATION PROBLEM Sue Ann Campbell Stephanie Crawford Kirsten Morris  

E-Print Network [OSTI]

FRICTION AND THE INVERTED PENDULUM STABILIZATION PROBLEM Sue Ann Campbell Stephanie Crawford of friction on the design and performance of feedback controllers that aim to stabilize the pendulum in the upright position. We show that a controller designed using a simple viscous friction model has poor

Morris, Kirsten

299

Advances in steam turbine technology for the power generation industry. PWR-Volume 26  

SciTech Connect (OSTI)

This is a collection of the papers on advances in steam turbine technology for the power generation industry presented at the 1994 International Joint Power Generation Conference. The topics include advances in steam turbine design, application of computational fluid dynamics to turbine aerodynamic design, life extension of fossil and nuclear powered steam turbine generators, solid particle erosion control technologies, and artificial intelligence, monitoring and diagnostics.

Moore, W.G. [ed.

1994-12-31T23:59:59.000Z

300

Part I:Part I: Degradation in 3.2 nm Gate Oxides:Degradation in 3.2 nm Gate Oxides: Effects on Inverter Performance and MOSFETEffects on Inverter Performance and MOSFET  

E-Print Network [OSTI]

on Inverter Performance and MOSFETEffects on Inverter Performance and MOSFET Characteristics.2 nm Gate Oxides: Effects on Inverter Performance and MOSFETEffects on Inverter Performance and MOSFET

Anlage, Steven

Note: This page contains sample records for the topic "turbine controllers inverters" 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

The Inverted Block Rate:The Inverted Block Rate: An Alternative to Flat Rate BillingAn Alternative to Flat Rate Billing  

E-Print Network [OSTI]

The Inverted Block Rate:The Inverted Block Rate: An Alternative to Flat Rate BillingAn Alternative;Inverted Block RateInverted Block Rate 22 IntroductionIntroduction ·· Modern societies rely on electrical collectionMetering and Rate Models facilitate collection #12;Inverted Block RateInverted Block Rate 33 Rate

Hughes, Larry

302

Wind Turbine Blockset General Overview  

E-Print Network [OSTI]

Wind Turbine Blockset in Saber General Overview and Description of the Models Florin Iov, Adrian Turbine Blockset in Saber Abstract. This report presents a new developed Saber Toolbox for wind turbine, optimize and design wind turbines". The report provides a quick overview of the Saber and then explains

303

Load attenuating passively adaptive wind turbine blade  

DOE Patents [OSTI]

A method and apparatus for improving wind turbine performance by alleviating loads and controlling the rotor. The invention employs the use of a passively adaptive blade that senses the wind velocity or rotational speed, and accordingly modifies its aerodynamic configuration. The invention exploits the load mitigation prospects of a blade that twists toward feather as it bends. The invention includes passively adaptive wind turbine rotors or blades with currently preferred power control features. The apparatus is a composite fiber horizontal axis wind-turbine blade, in which a substantial majority of fibers in the blade skin are inclined at angles of between 15 and 30 degrees to the axis of the blade, to produces passive adaptive aeroelastic tailoring (bend-twist coupling) to alleviate loading without unduly jeopardizing performance.

Veers, Paul S. (Albuquerque, NM); Lobitz, Donald W. (Albuquerque, NM)

2003-01-01T23:59:59.000Z

304

Load attenuating passively adaptive wind turbine blade  

DOE Patents [OSTI]

A method and apparatus for improving wind turbine performance by alleviating loads and controlling the rotor. The invention employs the use of a passively adaptive blade that senses the wind velocity or rotational speed, and accordingly modifies its aerodynamic configuration. The invention exploits the load mitigation prospects of a blade that twists toward feather as it bends. The invention includes passively adaptive wind turbine rotors or blades with currently preferred power control features. The apparatus is a composite fiber horizontal axis wind-turbine blade, in which a substantial majority of fibers in the blade skin are inclined at angles of between 15 and 30 degrees to the axis of the blade, to produces passive adaptive aeroelastic tailoring (bend-twist coupling) to alleviate loading without unduly jeopardizing performance.

Veers, Paul S.; Lobitz, Donald W.

2003-01-07T23:59:59.000Z

305

Cooled snubber structure for turbine blades  

DOE Patents [OSTI]

A turbine blade assembly in a turbine engine. The turbine blade assembly includes a turbine blade and a first snubber structure. The turbine blade includes an internal cooling passage containing cooling air. The first snubber structure extends outwardly from a sidewall of the turbine blade and includes a hollow interior portion that receives cooling air from the internal cooling passage of the turbine blade.

Mayer, Clinton A; Campbell, Christian X; Whalley, Andrew; Marra, John J

2014-04-01T23:59:59.000Z

306

Radar-cross-section reduction of wind turbines. part 1.  

SciTech Connect (OSTI)

In recent years, increasing deployment of large wind-turbine farms has become an issue of growing concern for the radar community. The large radar cross section (RCS) presented by wind turbines interferes with radar operation, and the Doppler shift caused by blade rotation causes problems identifying and tracking moving targets. Each new wind-turbine farm installation must be carefully evaluated for potential disruption of radar operation for air defense, air traffic control, weather sensing, and other applications. Several approaches currently exist to minimize conflict between wind-turbine farms and radar installations, including procedural adjustments, radar upgrades, and proper choice of low-impact wind-farm sites, but each has problems with limited effectiveness or prohibitive cost. An alternative approach, heretofore not technically feasible, is to reduce the RCS of wind turbines to the extent that they can be installed near existing radar installations. This report summarizes efforts to reduce wind-turbine RCS, with a particular emphasis on the blades. The report begins with a survey of the wind-turbine RCS-reduction literature to establish a baseline for comparison. The following topics are then addressed: electromagnetic model development and validation, novel material development, integration into wind-turbine fabrication processes, integrated-absorber design, and wind-turbine RCS modeling. Related topics of interest, including alternative mitigation techniques (procedural, at-the-radar, etc.), an introduction to RCS and electromagnetic scattering, and RCS-reduction modeling techniques, can be found in a previous report.

Brock, Billy C.; Loui, Hung; McDonald, Jacob J.; Paquette, Joshua A.; Calkins, David A.; Miller, William K.; Allen, Steven E.; Clem, Paul Gilbert; Patitz, Ward E.

2012-03-05T23:59:59.000Z

307

EV drivetrain inverter with V/HZ optimization  

DOE Patents [OSTI]

An inverter (34) which provides power to an A.C. machine (28) is controlled by a circuit (36) employing PWM control strategy whereby A.C. power is supplied to the machine at a preselectable frequency and preselectable voltage. This is accomplished by the technique of waveform notching in which the shapes of the notches are varied to determine the average energy content of the overall waveform. Through this arrangement, the operational efficiency of the A.C. machine is optimized. The control circuit includes a micro-computer which calculates optimized machine control data signals from various parametric inputs and during steady state load conditions, seeks a best V/HZ ratio to minimize battery current drawn (system losses) from a D.C. power source (32). In the preferred embodiment, the present invention is incorporated within an electric vehicle (10) employing a 144 VDC battery pack and a three-phase induction motor (18).

Gritter, David J. (Southfield, MI); O'Neil, Walter K. (Birmingham, MI)

1986-01-01T23:59:59.000Z

308

Wind Turbine Acoustic Noise A white paper  

E-Print Network [OSTI]

Wind Turbine Acoustic Noise A white paper Prepared by the Renewable Energy Research Laboratory...................................................................... 8 Sound from Wind Turbines .............................................................................................. 10 Sources of Wind Turbine Sound

Massachusetts at Amherst, University of

309

OVERLAY COATINGS FOR GAS TURBINE AIRFOILS  

E-Print Network [OSTI]

R. Krutenat, Gas Turbine Materials Conference Proceedings,Conference on Gas Turbine Materials in a Marine Environment,in developing new turbine materials, coatings and processes,

Boone, Donald H.

2013-01-01T23:59:59.000Z

310

Composite turbine bucket assembly  

DOE Patents [OSTI]

A composite turbine blade assembly includes a ceramic blade including an airfoil portion, a shank portion and an attachment portion; and a transition assembly adapted to attach the ceramic blade to a turbine disk or rotor, the transition assembly including first and second transition components clamped together, trapping said ceramic airfoil therebetween. Interior surfaces of the first and second transition portions are formed to mate with the shank portion and the attachment portion of the ceramic blade, and exterior surfaces of said first and second transition components are formed to include an attachment feature enabling the transition assembly to be attached to the turbine rotor or disk.

Liotta, Gary Charles; Garcia-Crespo, Andres

2014-05-20T23:59:59.000Z

311

Gas turbine combustor transition  

DOE Patents [OSTI]

A method is described for converting a steam cooled transition to an air cooled transition in a gas turbine having a compressor in fluid communication with a combustor, a turbine section in fluid communication with the combustor, the transition disposed in a combustor shell and having a cooling circuit connecting a steam outlet and a steam inlet and wherein hot gas flows from the combustor through the transition and to the turbine section, includes forming an air outlet in the transition in fluid communication with the cooling circuit and providing for an air inlet in the transition in fluid communication with the cooling circuit. 7 figs.

Coslow, B.J.; Whidden, G.L.

1999-05-25T23:59:59.000Z

312

Gas turbine combustor transition  

DOE Patents [OSTI]

A method of converting a steam cooled transition to an air cooled transition in a gas turbine having a compressor in fluid communication with a combustor, a turbine section in fluid communication with the combustor, the transition disposed in a combustor shell and having a cooling circuit connecting a steam outlet and a steam inlet and wherein hot gas flows from the combustor through the transition and to the turbine section, includes forming an air outlet in the transition in fluid communication with the cooling circuit and providing for an air inlet in the transition in fluid communication with the cooling circuit.

Coslow, Billy Joe (Winter Park, FL); Whidden, Graydon Lane (Great Blue, CT)

1999-01-01T23:59:59.000Z

313

46th Aerospace Sciences Meeting, January 7-10, 2008, Reno, Nevada A Smart Wind Turbine Blade Using Distributed  

E-Print Network [OSTI]

46th Aerospace Sciences Meeting, January 7-10, 2008, Reno, Nevada A Smart Wind Turbine Blade Using of "smart" wind turbine blades with integrated sensor-actuator-controller modules to im- prove

Nelson, Robert C.

314

Industrial Gas Turbines  

Broader source: Energy.gov [DOE]

A gas turbine is a heat engine that uses high-temperature, high-pressure gas as the working fluid. Part of the heat supplied by the gas is converted directly into mechanical work. High-temperature,...

315

Turbine nozzle positioning system  

DOE Patents [OSTI]

A nozzle guide vane assembly having a preestablished rate of thermal expansion is positioned in a gas turbine engine and being attached to conventional metallic components. The nozzle guide vane assembly includes an outer shroud having a mounting leg with an opening defined therein, a tip shoe ring having a mounting member with an opening defined therein, a nozzle support ring having a plurality of holes therein and a pin positioned in the corresponding opening in the outer shroud, opening in the tip shoe ring and the hole in the nozzle support ring. A rolling joint is provided between metallic components of the gas turbine engine and the nozzle guide vane assembly. The nozzle guide vane assembly is positioned radially about a central axis of the gas turbine engine and axially aligned with a combustor of the gas turbine engine.

Norton, Paul F. (San Diego, CA); Shaffer, James E. (Maitland, FL)

1996-01-30T23:59:59.000Z

316

Turbine nozzle positioning system  

DOE Patents [OSTI]

A nozzle guide vane assembly having a preestablished rate of thermal expansion is positioned in a gas turbine engine and being attached to conventional metallic components. The nozzle guide vane assembly includes an outer shroud having a mounting leg with an opening defined therein, a tip shoe ring having a mounting member with an opening defined therein, a nozzle support ring having a plurality of holes therein and a pin positioned in the corresponding opening in the outer shroud, opening in the tip shoe ring and the hole in the nozzle support ring. A rolling joint is provided between metallic components of the gas turbine engine and the nozzle guide vane assembly. The nozzle guide vane assembly is positioned radially about a central axis of the gas turbine engine and axially aligned with a combustor of the gas turbine engine. 9 figs.

Norton, P.F.; Shaffer, J.E.

1996-01-30T23:59:59.000Z

317

Advanced Photovoltaic Inverter Functionality using 500 kW Power Hardware-in-Loop Complete System Laboratory Testing: Preprint  

SciTech Connect (OSTI)

With the increasing penetration of distribution connected photovoltaic (PV) systems, more and more PV developers and utilities are interested in easing future PV interconnection concerns by mitigating some of the impacts of PV integration using advanced PV inverter controls and functions. This paper describes the testing of a 500 kW PV inverter using Power Hardware-in-Loop (PHIL) testing techniques. The test setup is described and the results from testing the inverter in advanced functionality modes, not commonly used in currently interconnected PV systems, are presented. PV inverter operation under PHIL evaluation that emulated both the DC PV array connection and the AC distribution level grid connection are shown for constant power factor (PF) and constant reactive power (VAr) control modes. The evaluation of these modes was completed under varying degrees of modeled PV variability.

Mather, B. A.; Kromer, M. A.; Casey, L.

2013-01-01T23:59:59.000Z

318

Coupled Dynamic Analysis of Multiple Unit Floating Offshore Wind Turbine  

E-Print Network [OSTI]

In the present study, a numerical simulation tool has been developed for the rotor-floater-tether coupled dynamic analysis of Multiple Unit Floating Offshore Wind Turbine (MUFOWT) in the time domain including aero-blade-tower dynamics and control...

Bae, Yoon Hyeok

2013-04-23T23:59:59.000Z

319

Variable diameter wind turbine rotor blades  

DOE Patents [OSTI]

A system and method for changing wind turbine rotor diameters to meet changing wind speeds and control system loads is disclosed. The rotor blades on the wind turbine are able to adjust length by extensions nested within or containing the base blade. The blades can have more than one extension in a variety of configurations. A cable winching system, a hydraulic system, a pneumatic system, inflatable or elastic extensions, and a spring-loaded jack knife deployment are some of the methods of adjustment. The extension is also protected from lightning by a grounding system.

Jamieson, Peter McKeich; Hornzee-Jones, Chris; Moroz, Emilian M.; Blakemore, Ralph W.

2005-12-06T23:59:59.000Z

320

E-Print Network 3.0 - advanced turbine systems-research Sample...  

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

models and advanced control strategies... .139) Track: Technical VARIABLE SPEED WIND TURBINES - FAULT RIDE-THROUGH AND GRID SUPPORT CAPABILITIES... is on the fault ride through...

Note: This page contains sample records for the topic "turbine controllers inverters" 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

E-Print Network 3.0 - advanced non-polluting turbine Sample Search...  

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

models and advanced control strategies... .139) Track: Technical VARIABLE SPEED WIND TURBINES - FAULT RIDE-THROUGH AND GRID SUPPORT CAPABILITIES... is on the fault ride through...

322

E-Print Network 3.0 - advanced multistage turbine Sample Search...  

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

models and advanced control strategies... .139) Track: Technical VARIABLE SPEED WIND TURBINES - FAULT RIDE-THROUGH AND GRID SUPPORT CAPABILITIES... is on the fault ride through...

323

E-Print Network 3.0 - advanced wind turbine Sample Search Results  

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

models and advanced control strategies... .139) Track: Technical VARIABLE SPEED WIND TURBINES - FAULT RIDE-THROUGH AND GRID SUPPORT CAPABILITIES... is on the fault ride through...

324

E-Print Network 3.0 - advanced hydropower turbine Sample Search...  

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

models and advanced control strategies... .139) Track: Technical VARIABLE SPEED WIND TURBINES - FAULT RIDE-THROUGH AND GRID SUPPORT CAPABILITIES... is on the fault ride through...

325

Summary of Inverter Technologies Prepared for the  

E-Print Network [OSTI]

Delivery and Energy Reliability Under Cooperative Agreement No. DE-EE0003507 Hawai`i Energy Sustainability Program Subtask 3.1 Photovoltaic Systems: Report 2 Summary of Inverter Technologies Submitted by Hawai [1]. Gridconnected photovoltaic (PV) installations, one of the most common types of DER, typically

326

Understanding Fault Characteristics of Inverter-Based Distributed Energy Resources  

SciTech Connect (OSTI)

This report discusses issues and provides solutions for dealing with fault current contributions from inverter-based distributed energy resources.

Keller, J.; Kroposki, B.

2010-01-01T23:59:59.000Z

327

Integrating Photovoltaic Inverter Reliability into Energy Yield Estimation with Markov Models  

E-Print Network [OSTI]

Integrating Photovoltaic Inverter Reliability into Energy Yield Estimation with Markov Models@illinois.edu Abstract-- Markov reliability models to estimate Photovoltaic (PV) inverter reliability of the inverters. Keywords-Photovoltaic energy conversion, Markov reliability models, utility-interactive inverters

Liberzon, Daniel

328

Steam turbine restart temperature maintenance system and method  

SciTech Connect (OSTI)

A restart temperature maintenance system is described for a steam turbine system; the steam turbine system comprising a steam turbine, the turbine including a rotation shaft, an outer metal shell means. The restart temperature maintenance system consists of: (a) fastener means affixed to the outer surface of the shell means at predetermined positions; (b) air gap spacer means affixed to the outer surface of the shell means, the air gap spacer means substantially covering the shell means; (c) a plurality of electric heating blanket means of predetermined size and shape positioned in insulative relationship over the air gap spacer means and the heating blanket means maintained in predetermined position by the fastener means; (d) heat sensor means affixed to the outer metal shell means of the steam turbine in predetermined position; (e) power supply means for supplying power to the heating blanket means; (f) heat sensor monitor and controller means connected in circuit between the power supply means and the heat sensor means.

McClelland, T.R.

1986-04-29T23:59:59.000Z

329

WIND TURBINE DRIVETRAIN TEST FACILITY DATA ACQUISITION SYSTEM  

SciTech Connect (OSTI)

The Wind Turbine Drivetrain Test Facility (WTDTF) is a state-of-the-art industrial facility used for testing wind turbine drivetrains and generators. Large power output wind turbines are primarily installed for off-shore wind power generation. The facility includes two test bays: one to accommodate turbine nacelles up to 7.5 MW and one for nacelles up to 15 MW. For each test bay, an independent data acquisition system (DAS) records signals from various sensors required for turbine testing. These signals include resistance temperature devices, current and voltage sensors, bridge/strain gauge transducers, charge amplifiers, and accelerometers. Each WTDTF DAS also interfaces with the drivetrain load applicator control system, electrical grid monitoring system and vibration analysis system.

Mcintosh, J.

2012-01-03T23:59:59.000Z

330

Invertible Symmetric 3 3 Binary Matrices and GQ(2, 4)  

E-Print Network [OSTI]

Invertible Symmetric 3 ? 3 Binary Matrices and GQ(2, 4) Andrea Blunck,1 P´eter L´evay,2 Metod of 27 (disregarding the identity) invertible symmetric 3 ? 3 matrices over GF(2) and the points of invertible symmetric 3 ? 3 matrices over the field GF(2) has 28 elements. The elements different from

Paris-Sud XI, Université de

331

Invertibility preservers on central simple algebras Peter Semrl  

E-Print Network [OSTI]

Invertibility preservers on central simple algebras Peter Semrl Faculty of Mathematics and Physics Kaplansky's problem concerning the structure of linear pre- servers of invertibility in the special case of maps on central simple alge- bras. AMS classification: 15A86, 16K20 Keywords: invertibility preserving

Semrl, Peter

332

What to Do When Your Hessian Is Not Invertible  

E-Print Network [OSTI]

What to Do When Your Hessian Is Not Invertible Alternatives to Model Respecification in Nonlinear is not invertable? The standard textbook advice is to respecify the model, but this is another way of saying for its inventor, German mathematician Ludwig Hesse) must be positive definite and hence invertible

Gill, Jeff

333

Experimental Investigation of Microwave Vulnerabilities in CMOS Inverters  

E-Print Network [OSTI]

Experimental Investigation of Microwave Vulnerabilities in CMOS Inverters Agis A. Iliadis effects on single CMOS inverters, the fundamental building block of logic ICs, consisting of an NMOS and a PMOS transistor. The inverters were designed in our group and fabricated in the AMI-1.5µm MOSIS line

Anlage, Steven

334

A Cascade Multilevel Inverter Using a Single DC Source  

E-Print Network [OSTI]

A Cascade Multilevel Inverter Using a Single DC Source Zhong Du1, Leon M. Tolbert2 3, John N inverter can be implemented using only a single DC power source and capacitors. A standard cascade multilevel inverter requires DC sources for 2 + 1 levels. Without requiring transformers, the scheme proposed

Tolbert, Leon M.

335

Supplement to "Power Algorithms for Inverting Laplace Transforms"  

E-Print Network [OSTI]

propose a new class of algorithms for numerically inverting Laplace transforms, called power algorithmsSupplement to "Power Algorithms for Inverting Laplace Transforms" Efstathios Avdis Department, with the parameter choice being tunable to the trans- form being inverted. The powers can be advantageously chosen

Whitt, Ward

336

Dual-speed wind turbine generation  

SciTech Connect (OSTI)

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)] [National Renewable Energy Lab., Golden, CO (United States); Handman, D. [Flowind Corp., San Rafael, CA (United States)] [Flowind Corp., San Rafael, CA (United States)

1996-10-01T23:59:59.000Z

337

A Novel Inductor-less DC-AC Cascaded H-bridge Multilevel Boost Inverter for Electric/Hybrid Electric Vehicle Applications  

SciTech Connect (OSTI)

This paper presents an inductorless cascaded H- bridge multilevel boost inverter for EV and HEV applications. Currently available power inverter systems for HEVs use a DC- DC boost converter to boost the battery voltage for a traditional 3-phase inverter. The present HEV traction drive inverters have low power density, are expensive, and have low efficiency because they need a bulky inductor. An inductorless cascaded H-bridge multilevel boost inverter for EV and HEV applications is proposed in this paper. Traditionally, each H-bridge needs a DC power supply. The proposed inductorless cascaded H-bridge multilevel boost inverter uses a standard 3-leg inverter (one leg for each phase) and an H-bridge in series with each inverter leg which uses a capacitor as the DC power source. Fundamental switching scheme is used to do modulation control and to produce a 5-level phase voltage. Experiments show that the proposed inductorless DC-AC cascaded H-bridge multilevel boost inverter can output a boosted AC voltage.

Du, Zhong [ORNL; Ozpineci, Burak [ORNL; Tolbert, Leon M [ORNL; Chiasson, John N [ORNL

2007-01-01T23:59:59.000Z

338

Performance Test Protocol for Evaluating Inverters Used in Grid-Connected  

E-Print Network [OSTI]

Performance Test Protocol for Evaluating Inverters Used in Grid-Connected Photovoltaic Systems....................................................................................... 6 4.1 Inverter Size

339

A Soft-Switching Inverter for High-Temperature Advanced Hybrid Electric Vehicle Traction Motor Drives  

SciTech Connect (OSTI)

The state-of-the-art hybrid electric vehicles (HEVs) require the inverter cooling system to have a separate loop to avoid power semiconductor junction over temperatures because the engine coolant temperature of 105?C does not allow for much temperature rise in silicon devices. The proposed work is to develop an advanced soft-switching inverter that will eliminate the device switching loss and cut down the power loss so that the inverter can operate at high-temperature conditions while operating at high switching frequencies with small current ripple in low inductance based permanent magnet motors. The proposed tasks also include high-temperature packaging and thermal modeling and simulation to ensure the packaged module can operate at the desired temperature. The developed module will be integrated with the motor and vehicle controller for dynamometer and in-vehicle testing to prove its superiority. This report will describe the detailed technical design of the soft-switching inverters and their test results. The experiments were conducted both in module level for the module conduction and switching characteristics and in inverter level for its efficiency under inductive and dynamometer load conditions. The performance will be compared with the DOE original specification.

None, None

2012-01-31T23:59:59.000Z

340

Qualification of Class 1E static battery charges and inverters for nuclear power generating stations  

SciTech Connect (OSTI)

This standard describes methods for qualifying static battery chargers and inverters for Class 1E installations in environmentally controlled areas outside containment in nuclear power generating stations. The purpose of this standard is to provide specific procedures to meet the requirements of IEEE Std. 323-1974.

Not Available

1981-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "turbine controllers inverters" 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

Design of Resonant Inverters for Optimal Efficiency over Lamp Life in Electronic Ballast  

E-Print Network [OSTI]

from a typical increase in an HID lamp equivalent resistance RI,, ovet its lifetime of more than 100 controlled resonant inverters to drive HID lamps. Considering the variation of the lamp resistance over its the lamp resistance during its Iifetime and system frequency range limitations. Design constraints have

342

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

E-Print Network [OSTI]

with the introduction of modern power generating units such as wind and solar power plants. As these new energy sourcesSmall-Signal Modeling of a Three-Phase Isolated Inverter with Both Voltage and Frequency Droop Rolla, Missouri 65409 Abstract-- In conventional power system operation, droop control methods are used

Kimball, Jonathan W.

343

Turbine inner shroud and turbine assembly containing such inner shroud  

DOE Patents [OSTI]

A turbine inner shroud and a turbine assembly. The turbine assembly includes a turbine stator having a longitudinal axis and having an outer shroud block with opposing and longitudinally outward facing first and second sides having open slots. A ceramic inner shroud has longitudinally inward facing hook portions which can longitudinally and radially surround a portion of the sides of the outer shroud block. In one attachment, the hook portions are engageable with, and are positioned within, the open slots.

Bagepalli, Bharat Sampathkumaran (Niskayuna, NY); Corman, Gregory Scot (Ballston Lake, NY); Dean, Anthony John (Scotia, NY); DiMascio, Paul Stephen (Clifton Park, NY); Mirdamadi, Massoud (Niskayuna, NY)

2001-01-01T23:59:59.000Z

344

Why Condensing Steam Turbines are More Efficient than Gas Turbines  

E-Print Network [OSTI]

WHY CONDENSING STEAM TURBINES ARE MORE EFFICIENT THAN GAS TURBINES KENNETH E. NELSON Associate Energy Consultant Dow Chemical U.S.A. Plaquemine. Louisiana INTRODUCTION AND ABSTRACT Consider the following questions: 1. Which is bigger... statement. however, is relevant to value. GAS TURBINE CYCLE Figure :> shows the enthalpy analysis for a gas turbine cycle employing a heat recovery unit for steam generation. Air enters the compressor where it's boosted to about 190 psi and mixed...

Nelson, K. E.

345

Investigation of self-excited induction generators for wind turbine applications  

SciTech Connect (OSTI)

The use of squirrel-cage induction machines in wind generation is widely accepted as a generator of choice. The squirrel-cage induction machine is simple, reliable, cheap, lightweight, and requires very little maintenance. Generally, the induction generator is connected to the utility at constant frequency. With a constant frequency operation, the induction generator operates at practically constant speed (small range of slip). The wind turbine operates in optimum efficiency only within a small range of wind speed variation. The variable-speed operation allows an increase in energy captured and reduces both the torque peaks in the drive train and the power fluctuations sent to the utility. In variable-speed operation, an induction generator needs an interface to convert the variable frequency output of the generator to the fixed frequency at the utility. This interface can be simplified by using a self-excited generator because a simple diode bridge is required to perform the ac/dc conversion. The subsequent dc/ac conversion can be performed using different techniques. The use of a thyristor bridge is readily available for large power conversion and has a lower cost and higher reliability. The firing angle of the inverter bridge can be controlled to track the optimum power curve of the wind turbine. With only diodes and thyristors used in power conversion, the system can be scaled up to a very high voltage and high power applications. This paper analyzes the operation of such a system applied to a 1/3-hp self-excited induction generator. It includes the simulations and tests performed for the different excitation configurations.

Muljadi, E.; Butterfield, C.P.; Sallan, J.; Sanz, M.

2000-02-28T23:59:59.000Z

346

Turbine tip clearance loss mechanisms  

E-Print Network [OSTI]

Three-dimensional numerical simulations (RANS and URANS) were used to assess the impact of two specific design features, and of aspects of the actual turbine environment, on turbine blade tip loss. The calculations were ...

Mazur, Steven (Steven Andrew)

2013-01-01T23:59:59.000Z

347

Ceramic stationary gas turbine  

SciTech Connect (OSTI)

The performance of current industrial gas turbines is limited by the temperature and strength capabilities of the metallic structural materials in the engine hot section. Because of their superior high-temperature strength and durability, ceramics can be used as structural materials for hot section components (blades, nozzles, combustor liners) in innovative designs at increased turbine firing temperatures. The benefits include the ability to increase the turbine inlet temperature (TIT) to about 1200{degrees}C ({approx}2200{degrees}F) or more with uncooled ceramics. It has been projected that fully optimized stationary gas turbines would have a {approx}20 percent gain in thermal efficiency and {approx}40 percent gain in output power in simple cycle compared to all metal-engines with air-cooled components. Annual fuel savings in cogeneration in the U.S. would be on the order of 0.2 Quad by 2010. Emissions reductions to under 10 ppmv NO{sub x} are also forecast. This paper describes the progress on a three-phase, 6-year program sponsored by the U.S. Department of Energy, Office of Industrial Technologies, to achieve significant performance improvements and emissions reductions in stationary gas turbines by replacing metallic hot section components with ceramic parts. Progress is being reported for the period September 1, 1994, through September 30, 1995.

Roode, M. van

1995-12-31T23:59:59.000Z

348

Zhiyu Jiang, Department of Marine Technology & Centre for Ships and Ocean Structures Dynamic response of wind turbines in fault and  

E-Print Network [OSTI]

response of wind turbines in fault and shutdown conditions Zhiyu Jiang Deptartment of Marine Technology://www.newscientist.com/blogs/onepercent/2011/12/why-did-a-wind-turbine-self-co.html #12;3 Zhiyu Jiang, Department of Marine Technology & Centre & Centre for Ships and Ocean Structures Control and protection of wind turbines Emergency shutdown Pitch

Nørvåg, Kjetil

349

7,511,624 Wind Energy Overview: Device for monitoring the balance and integrity of wind turbine blades either in  

E-Print Network [OSTI]

turbine blades either in service or as a quality control step in the manufacturing process Researchers oscillations (including imbalances and tracking variations) in wind turbine blades. This technology was tested covering the RPM rate of any wind turbine blade. This invention directly targets the operational monitoring

Maxwell, Bruce D.

350

Optimization of Wind Turbine Operation  

E-Print Network [OSTI]

Optimization of Wind Turbine Operation by Use of Spinner Anemometer TF Pedersen, NN Sørensen, L Title: Optimization of Wind Turbine Operation by Use of Spinner Anemometer Department: Wind Energy prototype wind turbine. Statistics of the yaw error showed an average of about 10°. The average flow

351

Gas turbine sealing apparatus  

DOE Patents [OSTI]

A gas turbine includes forward and aft rows of rotatable blades, a row of stationary vanes between the forward and aft rows of rotatable blades, an annular intermediate disc, and a seal housing apparatus. The forward and aft rows of rotatable blades are coupled to respective first and second portions of a disc/rotor assembly. The annular intermediate disc is coupled to the disc/rotor assembly so as to be rotatable with the disc/rotor assembly during operation of the gas turbine. The annular intermediate disc includes a forward side coupled to the first portion of the disc/rotor assembly and an aft side coupled to the second portion of the disc/rotor assembly. The seal housing apparatus is coupled to the annular intermediate disc so as to be rotatable with the annular intermediate disc and the disc/rotor assembly during operation of the gas turbine.

Wiebe, David J; Wessell, Brian J; Ebert, Todd; Beeck, Alexander; Liang, George; Marussich, Walter H

2013-02-19T23:59:59.000Z

352

Turbine nozzle attachment system  

DOE Patents [OSTI]

A nozzle guide vane assembly having a preestablished rate of thermal expansion is positioned in a gas turbine engine and is attached to conventional metallic components. The nozzle guide vane assembly includes a pair of legs extending radially outwardly from an outer shroud and a pair of mounting legs extending radially inwardly from an inner shroud. Each of the pair of legs and mounting legs have a pair of holes therein. A plurality of members attached to the gas turbine engine have a plurality of bores therein which axially align with corresponding ones of the pair of holes in the legs. A plurality of pins are positioned within the corresponding holes and bores radially positioning the nozzle guide vane assembly about a central axis of the gas turbine engine. 3 figs.

Norton, P.F.; Shaffer, J.E.

1995-10-24T23:59:59.000Z

353

Turbine nozzle attachment system  

DOE Patents [OSTI]

A nozzle guide vane assembly having a preestablished rate of thermal expansion is positioned in a gas turbine engine and being attached to conventional metallic components. The nozzle guide vane assembly includes a pair of legs extending radially outwardly from an outer shroud and a pair of mounting legs extending radially inwardly from an inner shroud. Each of the pair of legs and mounting legs have a pair of holes therein. A plurality of members attached to the gas turbine engine have a plurality of bores therein which axially align with corresponding ones of the pair of holes in the legs. A plurality of pins are positioned within the corresponding holes and bores radially positioning the nozzle guide vane assembly about a central axis of the gas turbine engine.

Norton, Paul F. (San Diego, CA); Shaffer, James E. (Maitland, FL)

1995-01-01T23:59:59.000Z

354

Non-invertible transformations and spatiotemporal randomness  

E-Print Network [OSTI]

We generalize the exact solution to the Bernoulli shift map. Under certain conditions, the generalized functions can produce unpredictable dynamics. We use the properties of the generalized functions to show that certain dynamical systems can generate random dynamics. For instance, the chaotic Chua's circuit coupled to a circuit with a non-invertible I-V characteristic can generate unpredictable dynamics. In general, a nonperiodic time-series with truncated exponential behavior can be converted into unpredictable dynamics using non-invertible transformations. Using a new theoretical framework for chaos and randomness, we investigate some classes of coupled map lattices. We show that, in some cases, these systems can produce completely unpredictable dynamics. In a similar fashion, we explain why some wellknown spatiotemporal systems have been found to produce very complex dynamics in numerical simulations. We discuss real physical systems that can generate random dynamics.

J. A. Gonzalez; A. J. Moreno; L. E. Guerrero

2006-02-12T23:59:59.000Z

355

Electron Cloud with Inverted Beam Screens  

E-Print Network [OSTI]

We report the results of computer simulations studying the effect of wrongly oriented LHC beam screens on the local electron-cloud heat load and density. At 3.5 or 7-TeV energy and for maximum secondary emission-yield values below 1.5, with the inverted sawtooth orientation about ten times higher heat load is expected than for the standard orientation, and the wrongly oriented sawtooth chambers could lead to a local heat-load bottleneck during the process of surface conditioning at 25-ns bunch spacing. The available cooling margin can be significantly increased by correcting the sawtooth orientations at least for two dipole magnets in LHC arc cells 26 and 32 R3, in order that there be no half-cell cooling loop containing more than one inverted screen.

Maury Cuna, H

2011-01-01T23:59:59.000Z

356

Fish-Friendly Hydropower Turbine Development & Deployment: Alden Turbine Preliminary Engineering and Model Testing  

SciTech Connect (OSTI)

The Alden turbine was developed through the U.S. Department of Energy's (DOE's) former Advanced Hydro Turbine Systems Program (1994-2006) and, more recently, through the Electric Power Research Institute (EPRI) and the DOE's Wind & Water Power Program. The primary goal of the engineering study described here was to provide a commercially competitive turbine design that would yield fish passage survival rates comparable to or better than the survival rates of bypassing or spilling flow. Although the turbine design was performed for site conditions corresponding to 92 ft (28 m) net head and a discharge of 1500 cfs (42.5 cms), the design can be modified for additional sites with differing operating conditions. During the turbine development, design modifications were identified for the spiral case, distributor (stay vanes and wicket gates), runner, and draft tube to improve turbine performance while maintaining features for high fish passage survival. Computational results for pressure change rates and shear within the runner passage were similar in the original and final turbine geometries, while predicted minimum pressures were higher for the final turbine. The final turbine geometry and resulting flow environments are expected to further enhance the fish passage characteristics of the turbine. Computational results for the final design were shown to improve turbine efficiencies by over 6% at the selected operating condition when compared to the original concept. Prior to the release of the hydraulic components for model fabrication, finite element analysis calculations were conducted for the stay vanes, wicket gates, and runner to verify that structural design criteria for stress and deflections were met. A physical model of the turbine was manufactured and tested with data collected for power and efficiency, cavitation limits, runaway speed, axial and radial thrust, pressure pulsations, and wicket gate torque. All parameters were observed to fall within ranges expected for conventional radial flow machines. Based on these measurements, the expected efficiency peak for prototype application is 93.64%. These data were used in the final sizing of the supporting mechanical and balance of plant equipment. The preliminary equipment cost for the design specification is $1450/kW with a total supply schedule of 28 months. This equipment supply includes turbine, generator, unit controls, limited balance of plant equipment, field installation, and commissioning. Based on the selected head and flow design conditions, fish passage survival through the final turbine is estimated to be approximately 98% for 7.9-inch (200-mm) fish, and the predicted survival reaches 100% for fish 3.9 inches (100 mm) and less in length. Note that fish up to 7.9- inches (200 mm) in length make up more than 90% of fish entrained at hydro projects in the United States. Completion of these efforts provides a mechanical and electrical design that can be readily adapted to site-specific conditions with additional engineering development comparable to costs associated with conventional turbine designs.

None

2011-10-01T23:59:59.000Z

357

Refurbishing steam turbines  

SciTech Connect (OSTI)

Power-plant operators are reducing maintenance costs of their aging steam turbines by using wire-arc spray coating and shot peening to prolong the service life of components, and by replacing outmoded bearings and seals with newer designs. Steam-turbine operators are pressed with the challenge of keeping their aging machines functioning in the face of wear problems that are exacerbated by the demand for higher efficiencies. These problems include intense thermal cycling during both start-up and shutdown, water particles in steam and solid particles in the air that pit smooth surfaces, and load changes that cause metal fatigue.

Valenti, M.

1997-12-01T23:59:59.000Z

358

Vertical axis wind turbines  

DOE Patents [OSTI]

A vertical axis wind turbine is described. The wind turbine can include a top ring, a middle ring and a lower ring, wherein a plurality of vertical airfoils are disposed between the rings. For example, three vertical airfoils can be attached between the upper ring and the middle ring. In addition, three more vertical airfoils can be attached between the lower ring and the middle ring. When wind contacts the vertically arranged airfoils the rings begin to spin. By connecting the rings to a center pole which spins an alternator, electricity can be generated from wind.

Krivcov, Vladimir (Miass, RU); Krivospitski, Vladimir (Miass, RU); Maksimov, Vasili (Miass, RU); Halstead, Richard (Rohnert Park, CA); Grahov, Jurij (Miass, RU)

2011-03-08T23:59:59.000Z

359

Ceramic gas turbine shroud  

DOE Patents [OSTI]

An example gas turbine engine shroud includes a first annular ceramic wall having an inner side for resisting high temperature turbine engine gasses and an outer side with a plurality of radial slots. A second annular metallic wall is positioned radially outwardly of and enclosing the first annular ceramic wall and has a plurality of tabs in communication with the slot of the first annular ceramic wall. The tabs of the second annular metallic wall and slots of the first annular ceramic wall are in communication such that the first annular ceramic wall and second annular metallic wall are affixed.

Shi, Jun; Green, Kevin E.

2014-07-22T23:59:59.000Z

360

Velocity pump reaction turbine  

DOE Patents [OSTI]

An expanding hydraulic/two-phase velocity pump reaction turbine including a dual concentric rotor configuration with an inter-rotor annular flow channel in which the inner rotor is mechanically driven by the outer rotor. In another embodiment, the inner rotor is immobilized and provided with gas recovery ports on its outer surface by means of which gas in solution may be recovered. This velocity pump reaction turbine configuration is capable of potential energy conversion efficiencies of up to 70%, and is particularly suited for geothermal applications.

House, Palmer A. (Walnut Creek, CA)

1982-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "turbine controllers inverters" 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

Velocity pump reaction turbine  

DOE Patents [OSTI]

An expanding hydraulic/two-phase velocity pump reaction turbine including a dual concentric rotor configuration with an inter-rotor annular flow channel in which the inner rotor is mechanically driven by the outer rotor. In another embodiment, the inner rotor is immobilized and provided with gas recovery ports on its outer surface by means of which gas in solution may be recovered. This velocity pump reaction turbine configuration is capable of potential energy conversion efficiencies of up to 70%, and is particularly suited for geothermal applications.

House, Palmer A. (Walnut Creek, CA)

1984-01-01T23:59:59.000Z

362

Multiple piece turbine airfoil  

DOE Patents [OSTI]

A turbine airfoil, such as a rotor blade or a stator vane, for a gas turbine engine, the airfoil formed as a shell and spar construction with a plurality of dog bone struts each mounted within openings formed within the shell and spar to allow for relative motion between the spar and shell in the airfoil chordwise direction while also forming a seal between adjacent cooling channels. The struts provide the seal as well as prevent bulging of the shell from the spar due to the cooling air pressure.

Kimmel, Keith D (Jupiter, FL); Wilson, Jr., Jack W. (Palm Beach Gardens, FL)

2010-11-02T23:59:59.000Z

363

Accelerating development of advanced inverters : evaluation of anti-islanding schemes with grid support functions and preliminary laboratory demonstration.  

SciTech Connect (OSTI)

The high penetration of utility interconnected photovoltaic (PV) systems is causing heightened concern over the effect that variable renewable generation will have on the electrical power system (EPS). These concerns have initiated the need to amend the utility interconnection standard to allow advanced inverter control functionalities that provide: (1) reactive power control for voltage support, (2) real power control for frequency support and (3) better tolerance of grid disturbances. These capabilities are aimed at minimizing the negative impact distributed PV systems may have on EPS voltage and frequency. Unfortunately, these advanced control functions may interfere with island detection schemes, and further development of advanced inverter functions requires a study of the effect of advanced functions on the efficacy of antiislanding schemes employed in industry. This report summarizes the analytical, simulation and experimental work to study interactions between advanced inverter functions and anti-islanding schemes being employed in distributed PV systems.

Neely, Jason C.; Gonzalez, Sigifredo; Ropp, Michael [Northern Plains Power Technologies, Brookings, SD] [Northern Plains Power Technologies, Brookings, SD; Schutz, Dustin [Northern Plains Power Technologies, Brookings, SD] [Northern Plains Power Technologies, Brookings, SD

2013-11-01T23:59:59.000Z

364

Status and Needs of Power Electronics for Photovoltaic Inverters  

SciTech Connect (OSTI)

Photovoltaics is the utility connected distributed energy resource (DER) that is in widespread use today. It has one element, the inverter, which is common with all DER sources except rotating generators. The inverter is required to transfer dc energy to ac energy. With all the DER technologies, (solar, wind, fuel cells, and microturbines) the inverter is still an immature product that will result in reliability problems in fielded systems. Today, the PV inverter is a costly and complex component of PV systems that produce ac power. Inverter MTFF (mean time to first failure) is currently unacceptable. Low inverter reliability contributes to unreliable fielded systems and a loss of confidence in renewable technology. The low volume of PV inverters produced restricts the manufacturing to small suppliers without sophisticated research and reliability programs or manufacturing methods. Thus, the present approach to PV inverter supply has low probability of meeting DOE reliability goals. DOE investments in power electronics are intended to address the reliability and cost of power electronics. This report details the progress of power electronics, identifies technologies that are in current use, and explores new approaches that can provide significant improvements in inverter reliability while leading to lower cost. A key element to improved inverter design is the systems approach to design. This approach includes a list of requirements for the product being designed and a preliminary requirements document is a part of this report. Finally, the design will be for a universal inverter that can be applied to several technologies. The objective of a universal inverter is to increase the quantity being manufactured so that mass-manufacturing techniques can be applied. The report includes the requirements and recommended design approaches for a new inverter with a ten-year mean time to first failure (MTFF) and with lower cost. This development will constitute a ''leap forward'' in capability that leverages emerging technologies and best manufacturing processes to produce a new, high reliability, inverter. The targeted inverter size is from two to ten kilowatts. The report is organized into four sections. A brief introduction by Sandia is followed by Section Two from Millennium Technologies (a company with UPS experience). Section Three is provided by Xantrex (a PV manufacturing company) and the University of Minnesota provided Section Four. This report is very detailed and provides inverter design information that is irrelevant to the layman. It is intended to be a comprehensive documentation of proven technology and the manufacturing skills required to produce a high reliability inverter. An accompanying report will provide a summary of the recommended approach for inverter development.

QIN, YU CHIN; MOHAN, NED; WEST, RICK; BONN, RUSSELL H.

2002-06-01T23:59:59.000Z

365

Advanced Turbine Systems Program: Conceptual design and product development  

SciTech Connect (OSTI)

Objective is to provide the conceptual design and product development plant for an ultra high efficiency, environmentally superior, and cost competitive industrial gas turbine system to be commercialized by the year 2000 (secondary objective is to begin early development of technologies critical to the success of ATS). This report addresses the remaining 7 of the 9 subtasks in Task 8, Design and Test of Critical Components: catalytic combustion, recuperator, high- temperature turbine disc, advanced control system, and ceramic materials.

NONE

1996-12-31T23:59:59.000Z

366

Turbine vane structure  

DOE Patents [OSTI]

A liquid cooled stator blade assembly for a gas turbine engine includes an outer shroud having a pair of liquid inlets and a pair of liquid outlets supplied through a header and wherein means including tubes support the header radially outwardly of the shroud and also couple the header with the pair of liquid inlets and outlets. A pair of turbine vanes extend radially between the shroud and a vane platform to define a gas turbine motive fluid passage therebetween; and each of the vanes is cooled by an internal body casting of super alloy material with a grooved layer of highly heat conductive material that includes spaced apart flat surface trailing edges in alignment with a flat trailing edge of the casting joined to wall segments of the liner which are juxtaposed with respect to the internal casting to form an array of parallel liquid inlet passages on one side of the vane and a second plurality of parallel liquid return passages on the opposite side of the vane; and a superalloy heat and wear resistant imperforate skin covers the outer surface of the composite blade including the internal casting and the heat conductive layer; a separate trailing edge section includes an internal casting and an outer skin butt connected to the end surfaces of the internal casting and the heat conductive layer to form an easily assembled liquid cooled trailing edge section in the turbine vane.

Irwin, John A. (Greenwood, IN)

1980-08-19T23:59:59.000Z

367

[1] DS/EN 61400-1: 2005. Wind turbines, part 1: Design requirements, 2005. [2] Andrew Delaney. Blowing up a storm. European Power News, 31, 2006.  

E-Print Network [OSTI]

[1] DS/EN 61400-1: 2005. Wind turbines, part 1: Design requirements, 2005. [2] Andrew Delaney loads of wind turbines. In Proceedings of the American Control Conference, Philadelphia, Pennsylvania, Fernando D. Bianchi, Hernán De Battista. Wind Turbine Control Systems. Springer, 2007. [6] H. Ganander

Pedersen, Henrik C.

368

Reducing emissions by addressing steam turbine inefficiencies  

SciTech Connect (OSTI)

This paper reports that inefficient steam turbines increase fossil plant emissions because additional fuel must be burned to meet the power output requirements. During a turbine outage, plant performance and maintenance staff make and prioritize repair decisions within tight time and budget constraints. This paper describes how Georgia Power identifies performance losses of degraded components in the steam path and determines their impact on heat rate. Turbine performance is assessed by a steam path audit program that Encotech has developed and make available to utilities. Georgia Power has conducted several operating tests that give good correlation with audit results. Georgia Power uses the audit information to make the most cost-effective repairs to maintain a low heat rate and to reduce emissions. The Clean Air Act presents electric utilities with the challenge of reducing emissions from fossil plants in the most cost-effective way possible. Meeting the stack emissions limitations often translates to large capital expenditures and increased cycle heat rate. One resource the electric utilities have to reduce the costly impact of compliance with the Clean Air Act is control over the efficiency of their steam turbines.

Harris, J.C. (Georgia Power Co., Atlanta, GA (United States)); Cioffi, D.H. (Encotech, Inc., Schenectady, NY (United States))

1992-01-01T23:59:59.000Z

369

Development of biomass as an alternative fuel for gas turbines  

SciTech Connect (OSTI)

A program to develop biomass as an alternative fuel for gas turbines was started at Aerospace Research Corporation in 1980. The research culminated in construction and installation of a power generation system using an Allison T-56 gas turbine at Red Boiling Springs, Tennessee. The system has been successfully operated with delivery of power to the Tennessee Valley Authority (TVA). Emissions from the system meet or exceed EPA requirements. No erosion of the turbine has been detected in over 760 hours of operation, 106 of which were on line generating power for the TVA. It was necessary to limit the turbine inlet temperature to 1450{degrees}F to control the rate of ash deposition on the turbine blades and stators and facilitate periodic cleaning of these components. Results of tests by researchers at Battelle Memorial Institute -- Columbus Division, give promise that deposits on the turbine blades, which must be periodically removed with milled walnut hulls, can be eliminated with addition of lime to the fuel. Operational problems, which are centered primarily around the feed system and engine configuration, have been adequately identified and can be corrected in an upgraded design. The system is now ready for development of a commercial version. The US Department of Energy (DOE) provided support only for the evaluation of wood as an alternative fuel for gas turbines. However, the system appears to have high potential for integration into a hybrid system for the production of ethanol from sorghum or sugar cane. 7 refs., 23 figs., 18 tabs.

Hamrick, J T [Aerospace Research Corp., Roanoke, VA (USA)

1991-04-01T23:59:59.000Z

370

Test Program for High Efficiency Gas Turbine Exhaust Diffuser  

SciTech Connect (OSTI)

This research relates to improving the efficiency of flow in a turbine exhaust, and thus, that of the turbine and power plant. The Phase I SBIR project demonstrated the technical viability of strutlets to control stalls on a model diffuser strut. Strutlets are a novel flow-improving vane concept intended to improve the efficiency of flow in turbine exhausts. Strutlets can help reduce turbine back pressure, and incrementally improve turbine efficiency, increase power, and reduce greenhouse gas emmission. The long-term goal is a 0.5 percent improvement of each item, averaged over the US gas turbine fleet. The strutlets were tested in a physical scale model of a gas turbine exhaust diffuser. The test flow passage is a straight, annular diffuser with three sets of struts. At the end of Phase 1, the ability of strutlets to keep flow attached to struts was demonstrated, but the strutlet drag was too high for a net efficiency advantage. An independently sponsored followup project did develop a highly-modified low-drag strutlet. In combination with other flow improving vanes, complicance to the stated goals was demonstrated for for simple cycle power plants, and to most of the goals for combined cycle power plants using this particular exhaust geometry. Importantly, low frequency diffuser noise was reduced by 5 dB or more, compared to the baseline. Appolicability to other diffuser geometries is yet to be demonstrated.

Norris, Thomas R.

2009-12-31T23:59:59.000Z

371

Effects of hydroelectric turbine passage on fish early life stages  

SciTech Connect (OSTI)

Turbine-passage mortality has been studied extensively for juveniles and adults of migratory fish species, but few studies have directly quantified mortality of fish eggs and larvae. An analysis of literature relating to component stresses of turbine passage (i.e., pressure changes, blade contact, and shear) indicates that mortality of early life stages of fish would be relatively low at low-head, bulb turbine installations. The shear forces and pressure regimes normally experienced are insufficient to cause high mortality rates. The probability of contact with turbine blades is related to the size of the fish; less than 5% of entrained ichthyoplankton would be killed by the blades in a bulb turbine. Other sources of mortality (e.g., cavitation and entrainment of fish acclimated to deep water) are controlled by operation of the facility and thus are mitigable. Because turbine-passage mortality among fish early life stages can be very difficult to estimate directly, it may be more fruitful to base the need for mitigation at any given site on detailed knowledge of turbine characteristics and the susceptibility of the fish community to entrainment. 7 refs., 1 fig.

Cada, G.F.

1991-01-01T23:59:59.000Z

372

Ris-PhD-24(EN) Stability and Control of Wind Farms in  

E-Print Network [OSTI]

, wind turbines substitute the power production of conventional power plants. Therefore, wind turbines. The project is based on simulations of wind turbines in a power system simulations tool. Some of the models speed turbine and its controls. To simulate realistic grid operation the wind turbine models

373

Turbine blade tip gap reduction system  

DOE Patents [OSTI]

A turbine blade sealing system for reducing a gap between a tip of a turbine blade and a stationary shroud of a turbine engine. The sealing system includes a plurality of flexible seal strips extending from a pressure side of a turbine blade generally orthogonal to the turbine blade. During operation of the turbine engine, the flexible seal strips flex radially outward extending towards the stationary shroud of the turbine engine, thereby reducing the leakage of air past the turbine blades and increasing the efficiency of the turbine engine.

Diakunchak, Ihor S.

2012-09-11T23:59:59.000Z

374

Power and Frequency Control as it Relates to Wind-Powered Generation  

E-Print Network [OSTI]

pressure controller of a steam turbine. For the purpose ofthe response of steam turbines to governing action: R = 0.05cycle plants. The steam turbines of these plants are most

Lacommare, Kristina S H

2011-01-01T23:59:59.000Z

375

Multilevel cascade voltage source inverter with seperate DC sources  

DOE Patents [OSTI]

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

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

1997-01-01T23:59:59.000Z

376

Multilevel cascade voltage source inverter with separate DC sources  

DOE Patents [OSTI]

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

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

1997-06-24T23:59:59.000Z

377

Multilevel cascade voltage source inverter with seperate DC sources  

DOE Patents [OSTI]

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

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

2002-01-01T23:59:59.000Z

378

Catalytic Combustion for Ultra-Low NOx Hydrogen Turbines  

SciTech Connect (OSTI)

Precision Combustion, Inc., (PCI) in close collaboration with Solar Turbines, Incorporated, has developed and demonstrated a combustion system for hydrogen fueled turbines that reduces NOx to low single digit level while maintaining or improving current levels of efficiency and eliminating emissions of carbon dioxide. Full scale Rich Catalytic Hydrogen (RCH1) injector was developed and successfully tested at Solar Turbines, Incorporated high pressure test facility demonstrating low single digit NOx emissions for hydrogen fuel in the range of 2200F-2750F. This development work was based on initial subscale development for faster turnaround and reduced cost. Subscale testing provided promising results for 42% and 52% H2 with NOx emissions of less than 2 ppm with improved flame stability. In addition, catalytic reactor element testing for substrate oxidation, thermal cyclic injector testing to simulate start-stop operation in a gas turbine environment, and steady state 15 atm. operation testing were performed successfully. The testing demonstrated stable and robust catalytic element component life for gas turbine conditions. The benefit of the catalytic hydrogen combustor technology includes capability of delivering near-zero NOx without costly post-combustion controls and without requirement for added sulfur control. In addition, reduced acoustics increase gas turbine component life. These advantages advances Department of Energy (DOEs) objectives for achievement of low single digit NOx emissions, improvement in efficiency vs. postcombustion controls, fuel flexibility, a significant net reduction in Integrated Gasification Combined Cycle (IGCC) system net capital and operating costs, and a route to commercialization across the power generation field from micro turbines to industrial and utility turbines.

Etemad, Shahrokh; Baird, Benjamin; Alavandi, Sandeep

2011-06-30T23:59:59.000Z

379

Vehicles - ORNL inverter licensed ... | ornl.gov  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched Ferromagnetism inS-4500IIVasudha Patri MechanicalofVehicles - ORNL inverter licensed

380

Data compression using inverted block codes  

E-Print Network [OSTI]

Fields 2. Minimum Distance and Error Correction 3. Matrix Notation for Codes 4. Cosets, Coset Leaders, and Maximum Likelihood Decoding C. Syndrome Decoding . D. Inversion of Codes E. Distortion Measure for Inverted Block Codes . F. Perfect Codes...+. The average distortion for block code C is found by averaging the word distortion measure of Equation 3. 3 over all codewords (n-tuples) x, so that p (C) = E[ (xlC)] = Q p(x)p. (?x). all x If the codewords are uniformly identically distributed, N...

McClellan, Stan

1991-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "turbine controllers inverters" 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

Integration of Novel Flux Coupling Motor and Current Source Inverter...  

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

of Novel Flux Coupling Motor and Current Source Inverter Novel Flux Coupling Machine without Permanent Magnets John Hsu, Oak Ridge National Laboratory, Flux Coupling...

382

High-Temperature, Air-Cooled Traction Drive Inverter Packaging  

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

Air-Cooled Traction Drive Inverter Packaging Madhu Chinthavali Oak Ridge National Laboratory June 10, 2010 Project ID: APE025 This presentation does not contain any proprietary,...

383

Vehicle Technologies Office Merit Review 2014: Next Generation Inverter  

Broader source: Energy.gov [DOE]

Presentation given by General Motors at 2014 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about next generation inverter.

384

Integration of Novel Flux Coupling Motor and Current Source Inverter  

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

To integrate a non permanent magnet (PM) electric machine and a current source inverter (CSI) *minimizing capacitors *eliminating rare earth materials used in traditional...

385

Methods and apparatus for twist bend coupled (TCB) wind turbine blades  

DOE Patents [OSTI]

A method for controlling a wind turbine having twist bend coupled rotor blades on a rotor mechanically coupled to a generator includes determining a speed of a rotor blade tip of the wind turbine, measuring a current twist distribution and current blade loading, and adjusting a torque of a generator to change the speed of the rotor blade tip to thereby increase an energy capture power coefficient of the wind turbine.

Moroz, Emilian Mieczyslaw; LeMieux, David Lawrence; Pierce, Kirk Gee

2006-10-10T23:59:59.000Z

386

Lightweight PV Inverters: Dual Bi-Directional IGBTs Modules Enables Breakthrough PV Inverter Using Current Modulation Topology  

SciTech Connect (OSTI)

Solar ADEPT Project: PV inverters convert DC power generated by modules into usable AC power. IPCs initial 30kW 94lb. PV inverter reduces the weight of comparable 30kW PV inverters by 90%reducing the cost of materials, manufacturing, shipping, and installation. With ARPA-E support, new bi-directional silicon power switches will be developed, commercialized, and utilized in IPCs next-generation PV inverter. With these components, IPC will produce 100kW inverters that weight less than 100lb., reducing the weight of conventional 3,000lb. 100kW inverters by more than 95%. The new power switches will cut IPCs $/W manufacturing cost in half, as well as further reduce indirect shipping and installation costs.

None

2012-01-30T23:59:59.000Z

387

10 IAEI NEWS September.October 2009 www.iaei.org connecting the inverter  

E-Print Network [OSTI]

10 IAEI NEWS September.October 2009 www.iaei.org connecting the inverter by John Wiles CONNECTING THE INVERTER CONNECTING THE INVERTER 10 IAEI NEWS September.October 2009 #12;www.iaei.org September.October 2009 IAEI NEWS 11 connecting the inverter C onnecting the utility-interactive inverter prop- erly

Johnson, Eric E.

388

Wind turbine reliability : a database and analysis approach.  

SciTech Connect (OSTI)

The US wind Industry has experienced remarkable growth since the turn of the century. At the same time, the physical size and electrical generation capabilities of wind turbines has also experienced remarkable growth. As the market continues to expand, and as wind generation continues to gain a significant share of the generation portfolio, the reliability of wind turbine technology becomes increasingly important. This report addresses how operations and maintenance costs are related to unreliability - that is the failures experienced by systems and components. Reliability tools are demonstrated, data needed to understand and catalog failure events is described, and practical wind turbine reliability models are illustrated, including preliminary results. This report also presents a continuing process of how to proceed with controlling industry requirements, needs, and expectations related to Reliability, Availability, Maintainability, and Safety. A simply stated goal of this process is to better understand and to improve the operable reliability of wind turbine installations.

Linsday, James (ARES Corporation); Briand, Daniel; Hill, Roger Ray; Stinebaugh, Jennifer A.; Benjamin, Allan S. (ARES Corporation)

2008-02-01T23:59:59.000Z

389

Dynamic simulation of dual-speed wind turbine generation  

SciTech Connect (OSTI)

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

390

Annual Report: Turbine Thermal Management (30 September 2013)  

SciTech Connect (OSTI)

The FY13 NETL-RUA Turbine Thermal Management effort supported the Department of Energys (DOE) Hydrogen Turbine Program through conduct of novel, fundamental, basic, and applied research in the areas of aerothermal heat transfer, coatings development, and secondary flow control. This research project utilized the extensive expertise and facilities readily available at NETL and the participating universities. The research approach included explorative studies based on scaled models and prototype coupon tests conducted under realistic high-temperature, pressurized, turbine operating conditions. This research is expected to render measurable outcomes that will meet DOEs advanced turbine development goals of a 3- to 5-point increase in power island efficiency and a 30 percent power increase above the hydrogen-fired combined cycle baseline. In addition, knowledge gained from this project will further advance the aerothermal cooling and TBC technologies in the general turbine community. This project has been structured to address: Development and design of aerothermal and materials concepts in FY12-13. Design and manufacturing of these advanced concepts in FY13. Bench-scale/proof-of-concept testing of these concepts in FY13-14 and beyond. In addition to a Project Management task, the Turbine Thermal Management project consists of four tasks that focus on a critical technology development in the areas of heat transfer, materials development, and secondary flow control. These include: Aerothermal and Heat Transfer Coatings and Materials Development Design Integration and Testing Secondary Flow Rotating Rig.

Alvin, Mary Anne; Richards, George

2014-04-10T23:59:59.000Z

391

Airborne Wind Turbine  

SciTech Connect (OSTI)

Broad Funding Opportunity Announcement Project: Makani Power is developing an Airborne Wind Turbine (AWT) that eliminates 90% of the mass of a conventional wind turbine and accesses a stronger, more consistent wind at altitudes of near 1,000 feet. At these altitudes, 85% of the country can offer viable wind resources compared to only 15% accessible with current technology. Additionally, the Makani Power wing can be economically deployed in deep offshore waters, opening up a resource which is 4 times greater than the entire U.S. electrical generation capacity. Makani Power has demonstrated the core technology, including autonomous launch, land, and power generation with an 8 meter wingspan, 20 kW prototype. At commercial scale, Makani Power aims to develop a 600 kW, 28 meter wingspan product capable of delivering energy at an unsubsidized cost competitive with coal, the current benchmark for low-cost power.

None

2010-09-01T23:59:59.000Z

392

Advanced Hydrogen Turbine Development  

SciTech Connect (OSTI)

Siemens has developed a roadmap to achieve the DOE goals for efficiency, cost reduction, and emissions through innovative approaches and novel technologies which build upon worldwide IGCC operational experience, platform technology, and extensive experience in G-class operating conditions. In Phase 1, the technologies and concepts necessary to achieve the program goals were identified for the gas turbine components and supporting technology areas and testing plans were developed to mitigate identified risks. Multiple studies were conducted to evaluate the impact in plant performance of different gas turbine and plant technologies. 2015 gas turbine technologies showed a significant improvement in IGCC plant efficiency, however, a severe performance penalty was calculated for high carbon capture cases. Thermodynamic calculations showed that the DOE 2010 and 2015 efficiency targets can be met with a two step approach. A risk management process was instituted in Phase 1 to identify risk and develop mitigation plans. For the risks identified, testing and development programs are in place and the risks will be revisited periodically to determine if changes to the plan are necessary. A compressor performance prediction has shown that the design of the compressor for the engine can be achieved with additional stages added to the rear of the compressor. Tip clearance effects were studied as well as a range of flow and pressure ratios to evaluate the impacts to both performance and stability. Considerable data was obtained on the four candidate combustion systems: diffusion, catalytic, premix, and distributed combustion. Based on the results of Phase 1, the premixed combustion system and the distributed combustion system were chosen as having the most potential and will be the focus of Phase 2 of the program. Significant progress was also made in obtaining combustion kinetics data for high hydrogen fuels. The Phase 1 turbine studies indicate initial feasibility of the advanced hydrogen turbine that meets the aggressive targets set forth for the advanced hydrogen turbine, including increased rotor inlet temperature (RIT), lower total cooling and leakage air (TCLA) flow, higher pressure ratio, and higher mass flow through the turbine compared to the baseline. Maintaining efficiency with high mass flow Syngas combustion is achieved using a large high AN2 blade 4, which has been identified as a significant advancement beyond the current state-of-the-art. Preliminary results showed feasibility of a rotor system capable of increased power output and operating conditions above the baseline. In addition, several concepts were developed for casing components to address higher operating conditions. Rare earth modified bond coat for the purpose of reducing oxidation and TBC spallation demonstrated an increase in TBC spallation life of almost 40%. The results from Phase 1 identified two TBC compositions which satisfy the thermal conductivity requirements and have demonstrated phase stability up to temperatures of 1850 C. The potential to join alloys using a bonding process has been demonstrated and initial HVOF spray deposition trials were promising. The qualitative ranking of alloys and coatings in environmental conditions was also performed using isothermal tests where significant variations in alloy degradation were observed as a function of gas composition. Initial basic system configuration schematics and working system descriptions have been produced to define key boundary data and support estimation of costs. Review of existing materials in use for hydrogen transportation show benefits or tradeoffs for materials that could be used in this type of applications. Hydrogen safety will become a larger risk than when using natural gas fuel as the work done to date in other areas has shown direct implications for this type of use. Studies were conducted which showed reduced CO{sub 2} and NOx emissions with increased plant efficiency. An approach to maximize plant output is needed in order to address the DOE turbine goal for 20-30% reduction o

Joesph Fadok

2008-01-01T23:59:59.000Z

393

Gas turbine cooling system  

DOE Patents [OSTI]

A gas turbine engine (10) having a closed-loop cooling circuit (39) for transferring heat from the hot turbine section (16) to the compressed air (24) produced by the compressor section (12). The closed-loop cooling system (39) includes a heat exchanger (40) disposed in the flow path of the compressed air (24) between the outlet of the compressor section (12) and the inlet of the combustor (14). A cooling fluid (50) may be driven by a pump (52) located outside of the engine casing (53) or a pump (54) mounted on the rotor shaft (17). The cooling circuit (39) may include an orifice (60) for causing the cooling fluid (50) to change from a liquid state to a gaseous state, thereby increasing the heat transfer capacity of the cooling circuit (39).

Bancalari, Eduardo E. (Orlando, FL)

2001-01-01T23:59:59.000Z

394

Multiple piece turbine airfoil  

DOE Patents [OSTI]

A turbine airfoil, such as a rotor blade or a stator vane, for a gas turbine engine, the airfoil formed as a shell and spar construction with a plurality of hook shaped struts each mounted within channels extending in a spanwise direction of the spar and the shell to allow for relative motion between the spar and shell in the airfoil chordwise direction while also fanning a seal between adjacent cooling channels. The struts provide the seal as well as prevent bulging of the shell from the spar due to the cooling air pressure. The hook struts have a hooked shaped end and a rounded shaped end in order to insert the struts into the spar.

Kimmel, Keith D (Jupiter, FL)

2010-11-09T23:59:59.000Z

395

Gas turbine sealing apparatus  

DOE Patents [OSTI]

A sealing apparatus in a gas turbine. The sealing apparatus includes a seal housing apparatus coupled to a disc/rotor assembly so as to be rotatable therewith during operation of the gas turbine. The seal housing apparatus comprises a base member, a first leg portion, a second leg portion, and spanning structure. The base member extends generally axially between forward and aft rows of rotatable blades and is positioned adjacent to a row of stationary vanes. The first leg portion extends radially inwardly from the base member and is coupled to the disc/rotor assembly. The second leg portion is axially spaced from the first leg portion, extends radially inwardly from the base member, and is coupled to the disc/rotor assembly. The spanning structure extends between and is rigidly coupled to each of the base member, the first leg portion, and the second leg portion.

Marra, John Joseph; Wessell, Brian J.; Liang, George

2013-03-05T23:59:59.000Z

396

Turbine seal assembly  

DOE Patents [OSTI]

A seal assembly that limits gas leakage from a hot gas path to one or more disc cavities in a turbine engine. The seal assembly includes a seal apparatus that limits gas leakage from the hot gas path to a respective one of the disc cavities. The seal apparatus comprises a plurality of blade members rotatable with a blade structure. The blade members are associated with the blade structure and extend toward adjacent stationary components. Each blade member includes a leading edge and a trailing edge, the leading edge of each blade member being located circumferentially in front of the blade member's corresponding trailing edge in a direction of rotation of the turbine rotor. The blade members are arranged such that a space having a component in a circumferential direction is defined between adjacent circumferentially spaced blade members.

Little, David A.

2013-04-16T23:59:59.000Z

397

Snubber assembly for turbine blades  

DOE Patents [OSTI]

A snubber associated with a rotatable turbine blade in a turbine engine, the turbine blade including a pressure sidewall and a suction sidewall opposed from the pressure wall. The snubber assembly includes a first snubber structure associated with the pressure sidewall of the turbine blade, a second snubber structure associated with the suction sidewall of the turbine blade, and a support structure. The support structure extends through the blade and is rigidly coupled at a first end portion thereof to the first snubber structure and at a second end portion thereof to the second snubber structure. Centrifugal loads exerted by the first and second snubber structures caused by rotation thereof during operation of the engine are at least partially transferred to the support structure, such that centrifugal loads exerted on the pressure and suctions sidewalls of the turbine blade by the first and second snubber structures are reduced.

Marra, John J

2013-09-03T23:59:59.000Z

398

Airfoils for wind turbine  

DOE Patents [OSTI]

Airfoils are disclosed for the blade of a wind turbine wherein each airfoil is characterized by a thickness in a range from 16%-24% and a maximum lift coefficient designed to be largely insensitive to roughness effects. The airfoils include a family of airfoils for a blade 15 to 25 meters in length, a family of airfoils for a blade 1 to 5 meters in length, and a family of airfoils for a blade 5 to 10 meters in length. 10 figs.

Tangler, J.L.; Somers, D.M.

1996-10-08T23:59:59.000Z

399

Airfoils for wind turbine  

DOE Patents [OSTI]

Airfoils for the blade of a wind turbine wherein each airfoil is characterized by a thickness in a range from 16%-24% and a maximum lift coefficient designed to be largely insensitive to roughness effects. The airfoils include a family of airfoils for a blade 15 to 25 meters in length, a family of airfoils for a blade 1 to 5 meters in length, and a family of airfoils for a blade 5 to 10 meters in length.

Tangler, James L. (Boulder, CO); Somers, Dan M. (State College, PA)

1996-01-01T23:59:59.000Z

400

Gas turbine premixing systems  

DOE Patents [OSTI]

Methods and systems are provided for premixing combustion fuel and air within gas turbines. In one embodiment, a combustor includes an upstream mixing panel configured to direct compressed air and combustion fuel through premixing zone to form a fuel-air mixture. The combustor includes a downstream mixing panel configured to mix additional combustion fuel with the fule-air mixture to form a combustion mixture.

Kraemer, Gilbert Otto; Varatharajan, Balachandar; Evulet, Andrei Tristan; Yilmaz, Ertan; Lacy, Benjamin Paul

2013-12-31T23:59:59.000Z

Note: This page contains sample records for the topic "turbine controllers inverters" 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

Computational Aerodynamics and Aeroacoustics for Wind Turbines  

E-Print Network [OSTI]

Computational Aerodynamics and Aeroacoustics for Wind Turbines #12;#12;Computational Aerodynamics and Aeroacoustics for Wind Turbines Wen Zhong Shen Fluid Mechanics Department of Mechanical Engineering TECHNICAL Shen, Wen Zhong Computational Aerodynamics and Aeroacoustics for Wind Turbines Doctor Thesis Technical

402

OVERLAY COATINGS FOR GAS TURBINE AIRFOILS  

E-Print Network [OSTI]

of Supperalloys for Gas Turbine Engines, 11 J. Metals, Q,OVERLAY COATINGS FOR GAS TURBINE AIRFOILS Donald H. Boone1970, p. 545. R. Krutenat, Gas Turbine Materials Conference

Boone, Donald H.

2013-01-01T23:59:59.000Z

403

Tornado type wind turbines  

DOE Patents [OSTI]

A tornado type wind turbine has a vertically disposed wind collecting tower with spaced apart inner and outer walls and a central bore. The upper end of the tower is open while the lower end of the structure is in communication with a wind intake chamber. An opening in the wind chamber is positioned over a turbine which is in driving communication with an electrical generator. An opening between the inner and outer walls at the lower end of the tower permits radially flowing air to enter the space between the inner and outer walls while a vertically disposed opening in the wind collecting tower permits tangentially flowing air to enter the central bore. A porous portion of the inner wall permits the radially flowing air to interact with the tangentially flowing air so as to create an intensified vortex flow which exits out of the top opening of the tower so as to create a low pressure core and thus draw air through the opening of the wind intake chamber so as to drive the turbine.

Hsu, Cheng-Ting (Ames, IA)

1984-01-01T23:59:59.000Z

404

High efficiency turbine blade coatings.  

SciTech Connect (OSTI)

The development of advanced thermal barrier coatings (TBCs) of yttria stabilized zirconia (YSZ) that exhibit lower thermal conductivity through better control of electron beam - physical vapor deposition (EB-PVD) processing is of prime interest to both the aerospace and power industries. This report summarizes the work performed under a two-year Lab-Directed Research and Development (LDRD) project (38664) to produce lower thermal conductivity, graded-layer thermal barrier coatings for turbine blades in an effort to increase the efficiency of high temperature gas turbines. This project was sponsored by the Nuclear Fuel Cycle Investment Area. Therefore, particular importance was given to the processing of the large blades required for industrial gas turbines proposed for use in the Brayton cycle of nuclear plants powered by high temperature gas-cooled reactors (HTGRs). During this modest (~1 full-time equivalent (FTE)) project, the processing technology was developed to create graded TBCs by coupling ion beam-assisted deposition (IBAD) with substrate pivoting in the alumina-YSZ system. The Electron Beam - 1200 kW (EB-1200) PVD system was used to deposit a variety of TBC coatings with micron layered microstructures and reduced thermal conductivity below 1.5 W/m.K. The use of IBAD produced fully stoichiometric coatings at a reduced substrate temperature of 600 oC and a reduced oxygen background pressure of 0.1 Pa. IBAD was also used to successfully demonstrate the transitioning of amorphous PVD-deposited alumina to the -phase alumina required as an oxygen diffusion barrier and for good adhesion to the substrate Ni2Al3 bondcoat. This process replaces the time consuming thermally grown oxide formation required before the YSZ deposition. In addition to the process technology, Direct Simulation Monte Carlo plume modeling and spectroscopic characterization of the PVD plumes were performed. The project consisted of five tasks. These included the production of layered periodic microstructures in the coating, the Direct Simulation Monte Carlo (DSMC) modeling of particle transport in the PVD plume, functional graded layer development, the deposition of all layers to form a complete coating, and materials characterization including thermal testing. Ion beam-assisted deposition, beam sharing through advanced digital rastering, substrate pivoting, hearth calorimetry, infrared imaging, fiber optic-enabled optical emission spectroscopy and careful thermal management were used to achieve all the milestones outlined in the FY02 LDRD proposal.

Youchison, Dennis L.; Gallis, Michail A.

2014-06-01T23:59:59.000Z

405

How to Build a Turbine  

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

Turbine Sign In About | Careers | Contact | Investors | bpa.gov Search News & Us Expand News & Us Projects & Initiatives Expand Projects & Initiatives Finance & Rates...

406

Integral Input-to-State Stability of the Drive-Train of a Wind Turbine Chen Wang and George Weiss  

E-Print Network [OSTI]

systems are responsible for generator torque control, pitch control and yaw control (the latter on the mechanical level of the turbine system, more precisely on the drive-train with the standard quadratic of the generator torque. We show that the turbine system is integral input-to-state stable. I. INTRODUCTION

Sontag, Eduardo

407

Advanced Manufacturing Initiative Improves Turbine Blade Productivity...  

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

Advanced Manufacturing Initiative Improves Turbine Blade Productivity Advanced Manufacturing Initiative Improves Turbine Blade Productivity May 20, 2011 - 2:56pm Addthis This is an...

408

turbine thermal index | netl.doe.gov  

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

obtained through this project can directly benefit the U.S. power and utility turbine industry by improving product development that specifically meets DOE advanced turbine program...

409

Addressing Wind Turbine Tribological Challenges with Surface...  

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

Addressing Wind Turbine Tribological Challenges with Surface Engineering Presented by Gary Doll of the University of Akron at the Wind Turbine Tribology Seminar 2014. Addressing...

410

A Segmented Drive Inverter Topology with a Small DC Bus Capacitor  

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

weight for inverters. Currently, it contributes - Cost and weight, up to 23% of an inverter - Volume, up to 30% of an inverter * Ability of film capacitors to operate at higher...

411

Left invertibility, flatness and identifiability of switched linear dynamical systems: a framework  

E-Print Network [OSTI]

Left invertibility, flatness and identifiability of switched linear dynamical systems: a framework invertibility and flatness, dynamical systems are structurally equivalent to some specific cryptographic invertibility, flatness and identifiability of discrete- time switched linear systems are investigated

Paris-Sud XI, Université de

412

Introduction Inverted index Processing Boolean queries Query optimization Web Search and Text Mining  

E-Print Network [OSTI]

Introduction Inverted index Processing Boolean queries Query optimization Web Search and Text Institute of Technology, College of Computing 2011 Gray: Boolean Retrieval 1 / 39 #12;Introduction Inverted index Processing Boolean queries Query optimization Overview 1 Introduction 2 Inverted index 3

Gray, Alexander

413

Large steam turbine repair: A survey  

SciTech Connect (OSTI)

This report covers a survey taken to document the current state-of-the-art in repairs to large steam turbines. One objective was to provide information to assist utilities in making repair or replacement decisions. The survey revealed that a large number of repairs have been successfully repaired involving both mechanical and welding repair techniques. Repair techniques have been improving in recent years and are being used more frequently. No guidelines or codes exist for the repair of steam turbine components so each repair is primarily controlled by agreement between the utility, contractor and insurer. Types of repairs are reviewed in this report and in addition, the capabilities of various contractors who are currently active in providing repair service. 40 refs., 10 figs., 4 tabs.

Findlan, S.J.; Lube, B. (EPRI Nondestructive Evaluation Center, Charlotte, NC (United States))

1991-07-01T23:59:59.000Z

414

Development and Simulation of Mathematical Modelling of Hydraulic Turbine  

E-Print Network [OSTI]

Abstract- Power system performance is affected by dynamic characteristics of hydraulic governor-turbines during and following any disturbance, such as occurrence of a fault, loss of a transmission line or a rapid change of load. Accurate modelling of hydraulic System is essential to characterize and diagnose the system response. In this article the mathematical modeling of hydraulic turbine is presented. The model is capable to implement the digital systems for monitoring and control replacing the conventional control systems for power, frequency and voltage. This paper presents the possibilities of modeling and simulation of the hydro power plants and performs an analysis of different control structures and algorithms. Key words: mathematical modeling, simulation, hydraulic turbine. I.

Gagan Singh; D. S. Chauhan

415

New Environmentally Friendly Dispersants for High Temperature Invert-Emulsion Drilling Fluids Weighted by Manganese Tetraoxide  

E-Print Network [OSTI]

filtration. 3. Specific fluid weight is required to hydrostatically balance formation pressures and to control the well column. The desired fluid density is attained by addition of weighting agents like barite and calcium carbonate. OBMs are water...) minimized drilling problems related to water-sensitive shales. Also, Bennett (1984) mentioned that mineral-oil based invert-emulsion fluids have greater tolerance to the contaminants such as carbonates, hydrogen sulfide, anhydrite, salt, or cement...

Rehman, Abdul

2012-02-14T23:59:59.000Z

416

Wind turbine reliability : understanding and minimizing wind turbine operation and maintenance costs.  

SciTech Connect (OSTI)

Wind turbine system reliability is a critical factor in the success of a wind energy project. Poor reliability directly affects both the project's revenue stream through increased operation and maintenance (O&M) costs and reduced availability to generate power due to turbine downtime. Indirectly, the acceptance of wind-generated power by the financial and developer communities as a viable enterprise is influenced by the risk associated with the capital equipment reliability; increased risk, or at least the perception of increased risk, is generally accompanied by increased financing fees or interest rates. Cost of energy (COE) is a key project evaluation metric, both in commercial applications and in the U.S. federal wind energy program. To reflect this commercial reality, the wind energy research community has adopted COE as a decision-making and technology evaluation metric. The COE metric accounts for the effects of reliability through levelized replacement cost and unscheduled maintenance cost parameters. However, unlike the other cost contributors, such as initial capital investment and scheduled maintenance and operating expenses, costs associated with component failures are necessarily speculative. They are based on assumptions about the reliability of components that in many cases have not been operated for a complete life cycle. Due to the logistical and practical difficulty of replacing major components in a wind turbine, unanticipated failures (especially serial failures) can have a large impact on the economics of a project. The uncertainty associated with long-term component reliability has direct bearing on the confidence level associated with COE projections. In addition, wind turbine technology is evolving. New materials and designs are being incorporated in contemporary wind turbines with the ultimate goal of reducing weight, controlling loads, and improving energy capture. While the goal of these innovations is reduction in the COE, there is a potential impact on reliability whenever new technologies are introduced. While some of these innovations may ultimately improve reliability, in the short term, the technology risks and the perception of risk will increase. The COE metric used by researchers to evaluate technologies does not address this issue. This paper outlines the issues relevant to wind turbine reliability for wind turbine power generation projects. The first sections describe the current state of the industry, identify the cost elements associated with wind farm O&M and availability and discuss the causes of uncertainty in estimating wind turbine component reliability. The latter sections discuss the means for reducing O&M costs and propose O&M related research and development efforts that could be pursued by the wind energy research community to reduce COE.

Not Available

2004-11-01T23:59:59.000Z

417

Industrial Applications of Networked Control Karl H. Johansson  

E-Print Network [OSTI]

of turbine + heater Automatic control of ventilation fans Mining consists of drilling, blasting, ore control of turbine + heater Controller Turbine- Ventilation Fan Tubes- Primary system Secondary system network rooms Pressure WSN Mobile WSN Automatic control of ventilation fans Mobility and reconfiguration

Johansson, Karl Henrik

418

Optimization of a Small Passive Wind Turbine Generator with Multiobjective Genetic Algorithms  

E-Print Network [OSTI]

: Multiobjective Optimization, Genetic Algorithms, Wind Energy, Vertical Axis Wind Turbine hal-00763673,version1 achieved by controlling the speed of a Wind Turbine Generator (WTG). In particular, the rotor speed should vary in accordance with the wind speed by maintaining the tip speed ratio to the value that maximizes

Paris-Sud XI, Université de

419

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

SciTech Connect (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

420

Does the world need yet another solar inverter concept? Intermediate size inverters have grown; now there is a  

E-Print Network [OSTI]

of the inverter with respect to the economics of solar generated electricity. Nextronex Energy Systems LLC, formed and specifiers, and concluded that the world would benefit from yet another solar inverter concept, one that we a critical interest in the revenue stream, uptime, and operation and maintenance cost of solar projects

King, Roger

Note: This page contains sample records for the topic "turbine controllers inverters" 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

NEXT GENERATION TURBINE PROGRAM  

SciTech Connect (OSTI)

The Next Generation Turbine (NGT) Program's technological development focused on a study of the feasibility of turbine systems greater than 30 MW that offer improvement over the 1999 state-of-the-art systems. This program targeted goals of 50 percent turndown ratios, 15 percent reduction in generation cost/kW hour, improved service life, reduced emissions, 400 starts/year with 10 minutes to full load, and multiple fuel usage. Improvement in reliability, availability, and maintainability (RAM), while reducing operations, maintenance, and capital costs by 15 percent, was pursued. This program builds on the extensive low emissions stationary gas turbine work being carried out by Pratt & Whitney (P&W) for P&W Power Systems (PWPS), which is a company under the auspices of the United Technologies Corporation (UTC). This study was part of the overall Department of Energy (DOE) NGT Program that extends out to the year 2008. A follow-on plan for further full-scale component hardware testing is conceptualized for years 2002 through 2008 to insure a smooth and efficient transition to the marketplace for advanced turbine design and cycle technology. This program teamed the National Energy Technology Laboratory (NETL), P&W, United Technologies Research Center (UTRC), kraftWork Systems Inc., a subcontractor on-site at UTRC, and Multiphase Power and Processing Technologies (MPPT), an off-site subcontractor. Under the auspices of the NGT Program, a series of analyses were performed to identify the NGT engine system's ability to serve multiple uses. The majority were in conjunction with a coal-fired plant, or used coal as the system fuel. Identified also was the ability of the NGT system to serve as the basis of an advanced performance cycle: the humid air turbine (HAT) cycle. The HAT cycle is also used with coal gasification in an integrated cycle HAT (IGHAT). The NGT systems identified were: (1) Feedwater heating retrofit to an existing coal-fired steam plant, which could supply both heat and peaking power (Block 2 engine); (2) Repowering of an older coal-fired plant (Block 2 engine); (3) Gas-fired HAT cycle (Block 1 and 2 engines); (4) Integrated gasification HAT (Block 1 and 2 engines). Also under Phase I of the NGT Program, a conceptual design of the combustion system has been completed. An integrated approach to cycle optimization for improved combustor turndown capability has been employed. The configuration selected has the potential for achieving single digit NO{sub x}/CO emissions between 40 percent and 100 percent load conditions. A technology maturation plan for the combustion system has been proposed. Also, as a result of Phase I, ceramic vane technology will be incorporated into NGT designs and will require less cooling flow than conventional metallic vanes, thereby improving engine efficiency. A common 50 Hz and 60 Hz power turbine was selected due to the cost savings from eliminating a gearbox. A list of ceramic vane technologies has been identified for which the funding comes from DOE, NASA, the U.S. Air Force, and P&W.

William H. Day

2002-05-03T23:59:59.000Z

422

MODIFYING AN INVERTED LABORATORY MICROSCOPE FOR RAMAN Presented in Partial Fulfillment of the Requirements for  

E-Print Network [OSTI]

MODIFYING AN INVERTED LABORATORY MICROSCOPE FOR RAMAN MICROSCOPY A Thesis Presented in Partial modifications a spectroscopic imaging instrument, a Raman microscope, can be constructed from a common inverted

423

Environmental Effects of Hydrokinetic Turbines on Fish: Desktop and Laboratory Flume Studies  

SciTech Connect (OSTI)

This collection of three reports describes desktop and laboratory flume studies that provide information to support assessment of the potential for injury and mortality of fish that encounter hydrokinetic turbines of various designs installed in tidal and river environments. Behavioral responses to turbine exposure also are investigated to support assessment of the potential for disruptions to upstream and downstream movements of fish. The studies: (1) conducted an assessment of potential injury mechanisms using available data from studies with conventional hydro turbines; (2) developed theoretical models for predicting blade strike probabilities and mortality rates; and (3) performed flume testing with three turbine designs and several fish species and size groups in two laboratory flumes to estimate survival rates and document fish behavior. The project yielded three reports which this document comprises. The three constituent documents are addressed individually below Fish Passage Through Turbines: Application of Conventional Hydropower Data to Hydrokinetic Technologies Fish passing through the blade sweep of a hydrokinetic turbine experience a much less harsh physical environment than do fish entrained through conventional hydro turbines. The design and operation of conventional turbines results in high flow velocities, abrupt changes in flow direction, relatively high runner rotational and blade speeds, rapid and significant changes in pressure, and the need for various structures throughout the turbine passageway that can be impacted by fish. These conditions generally do not occur or are not significant factors for hydrokinetic turbines. Furthermore, compared to conventional hydro turbines, hydrokinetic turbines typically produce relatively minor changes in shear, turbulence, and pressure levels from ambient conditions in the surrounding environment. Injuries and mortality from mechanical injuries will be less as well, mainly due to low rotational speeds and strike velocities, and an absence of structures that can lead to grinding or abrasion injuries. Additional information is needed to rigorously assess the nature and magnitude of effects on individuals and populations, and to refine criteria for design of more fish-friendly hydrokinetic turbines. Evaluation of Fish Injury and Mortality Associated with Hydrokinetic Turbines Flume studies exposed fish to two hydrokinetic turbine designs to determine injury and survival rates and to assess behavioral responses. Also, a theoretical model developed for predicting strike probability and mortality of fish passing through conventional hydro turbines was adapted for use with hydrokinetic turbines and applied to the two designs evaluated during flume studies. The flume tests were conducted with the Lucid spherical turbine (LST), a Darrieus-type (cross flow) turbine, and the Welka UPG, an axial flow propeller turbine. Survival rates for rainbow trout tested with the LST were greater than 98% for both size groups and approach velocities evaluated. Turbine passage survival rates for rainbow trout and largemouth bass tested with the Welka UPG were greater than 99% for both size groups and velocities evaluated. Injury rates of turbine-exposed fish were low with both turbines and generally comparable to control fish. Video observations of the LST demonstrated active avoidance of turbine passage by a large proportion fish despite being released about 25 cm upstream of the turbine blade sweep. Video observations from behavior trials indicated few if any fish pass through the turbines when released farther upstream. The theoretical predictions for the LST indicated that strike mortality would begin to occur at an ambient current velocity of about 1.7 m/s for fish with lengths greater than the thickness of the leading edge of the blades. As current velocities increase above 1.7 m/s, survival was predicted to decrease for fish passing through the LST, but generally remained high (greater than 90%) for fish less than 200 mm in length. Strike mortality was not predicted to occur duri

Jacobson, Paul T. [Electric Power Research Institute; Amaral, Stephen V. [Alden Research Laboratory; Castro-Santos, Theodore [U.S. Geological Survey; Giza, Dan [Alden Research Laboratory; Haro, Alexander J. [U.S. Geological Survey; Hecker, George [Alden Research Laboratory; McMahon, Brian [Alden Research Laboratory; Perkins, Norman [Alden Research Laboratory; Pioppi, Nick [Alden Research Laboratory

2012-12-31T23:59:59.000Z

424

Optimum propeller wind turbines  

SciTech Connect (OSTI)

The Prandtl-Betz-Theodorsen theory of heavily loaded airscrews has been adapted to the design of propeller windmills which are to be optimized for maximum power coefficient. It is shown that the simpler, light-loading, constant-area wake assumption can generate significantly different ''optimum'' performance and geometry, and that it is therefore not appropriate to the design of propeller wind turbines when operating in their normal range of high-tip-speed-to-wind-speed ratio. Design curves for optimum power coefficient are presented and an example of the design of a typical two-blade optimum rotor is given.

Sanderson, R.J.; Archer, R.D.

1983-11-01T23:59:59.000Z

425

IEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 22, NO. 3, MAY 2007 815 Design of Resonant Inverters for Optimal Efficiency  

E-Print Network [OSTI]

IEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 22, NO. 3, MAY 2007 815 Design of Resonant Inverters for Optimal Efficiency Over Lamp Life in Electronic Ballast With Phase Control Francisco J. Azcondo, Senior was presented in part at The 20th Annual IEEE Applied Power Electronics Conference and Exposition (APEC'05

426

Combined Heat and Power Plant Steam Turbine  

E-Print Network [OSTI]

Combined Heat and Power Plant Steam Turbine Steam Turbine Chiller Campus Heat Load Steam (recovered waste heat) Gas Turbine University Substation High Pressure Natural Gas Campus Electric Load Southern Generator Heat Recovery Alternative Uses: 1. Campus heating load 2. Steam turbine chiller to campus cooling

Rose, Michael R.

427

Installing Small Wind Turbines Seminar and Workshop  

E-Print Network [OSTI]

Seminar and Workshop Installing Small Wind Turbines Seminar and Workshop Location: Murdoch January 2011 Details for Registration and Payment: Mr Daniel Jones, National Small Wind Turbine Test: The National Small Wind Turbine Centre at Murdoch University is holding a Small Wind Turbine short training

428

AIAA 20033698 Aircraft Gas Turbine Engine  

E-Print Network [OSTI]

AIAA 2003­3698 Aircraft Gas Turbine Engine Simulations W. C. Reynolds , J. J. Alonso, and M. Fatica, Reston, VA 20191­4344 #12;AIAA 2003­3698 Aircraft Gas Turbine Engine Simulations W. C. Reynolds , J. J of the flowpath through complete aircraft gas turbines including the compressor, combustor, turbine, and secondary

Stanford University

429

Potential of innovative ceramics for turbine  

E-Print Network [OSTI]

Potential of innovative ceramics for turbine applications. A. Jankowiak, R. Valle, M. Parlier ODAS ceramics for turbine applications. Potentiel de céramiques innovantes pour des applications turbines par A. Jankowiak, R. Valle, M. Parlier Résumé traduit : L'amélioration du rendement thermique des turbines à gaz d

430

5th International Meeting Wind Turbine Noise  

E-Print Network [OSTI]

1 5th International Meeting on Wind Turbine Noise Denver 28 ­ 30 August 2013 Wind Turbine Noise Broadband noise generated aerodynamically is the dominant noise source for a modern wind turbine(Brooks et turbines . First, a wall pressure spectral model proposed recently by Rozenberg, Robert and Moreau

Paris-Sud XI, Université de

431

Method for pressure modulation of turbine sidewall cavities  

DOE Patents [OSTI]

A method is provided for controlling cooling air flow for pressure modulation of turbine components, such as the turbine outer sidewall cavities. The pressure at which cooling and purge air is supplied to the turbine outer side wall cavities is modulated, based on compressor discharge pressure (Pcd), thereby to generally maintain the back flow margin (BFM) so as to minimize excessive leakage and the consequent performance deterioration. In an exemplary embodiment, the air pressure within the third stage outer side wall cavity and the air pressure within the fourth stage outer side wall cavity are each controlled to a respective value that is a respective prescribed percentage of the concurrent compressor discharge pressure. The prescribed percentage may be determined from a ratio of the respective outer side wall pressure to compressor discharge pressure at Cold Day Turn Down (CDTD) required to provide a prescribed back flow margin.

Leone, Sal Albert (Scotia, NY); Book, Matthew David (Altamont, NY); Banares, Christopher R. (Schenectady, NY)

2002-01-01T23:59:59.000Z

432

System for pressure modulation of turbine sidewall cavities  

DOE Patents [OSTI]

A system and method are provided for controlling cooling air flow for pressure modulation of turbine components, such as the turbine outer sidewall cavities. The pressure at which cooling and purge air is supplied to the turbine outer side wall cavities is modulated, based on compressor discharge pressure (Pcd), thereby to generally maintain the back flow margin (BFM) so as to minimize excessive leakage and the consequent performance deterioration. In an exemplary embodiment, the air pressure within the third stage outer side wall cavity and the air pressure within the fourth stage outer side wall cavity are each controlled to a respective value that is a respective prescribed percentage of the concurrent compressor discharge pressure. The prescribed percentage may be determined from a ratio of the respective outer side wall pressure to compressor discharge pressure at Cold Day Turn Down (CDTD) required to provide a prescribed back flow margin.

Leone, Sal Albert (Scotia, NY); Book, Matthew David (Altamont, NY); Banares, Christopher R. (Schenectady, NY)

2002-01-01T23:59:59.000Z

433

Radial Inflow Gas Turbine Flow Path Design  

E-Print Network [OSTI]

Abstract:- A new method for radial inflow gas turbine flow paths design based on a unique integrated conceptual design environment AxSTREAM is presented in this paper. This integrated environment is a seamless and swift processing scheme that incorporates stages aerodynamic analysis and preliminary design/sizing based on the one dimensional method. The environment makes possible to find number of different designs with inverse task solver, basing on initially specified boundary conditions, closing conditions and design variables. Design space explorer provides easy and visual comparison for range of obtained design in customizable coordinate axes. Solution filtering on different parameters, such as meridional and axial dimensions, maximal blades weight, saving the time to choose from thousands obtained solutions the only one right design. Flexibility of presented approach allows to built-up complete gas turbine flow path from consequence of individual elements: stationary and rotating elements, ducts, heat exchangers, and analyze it in common environment. Complete control of all aspects of aerodynamic flow path quality, structural reliability, and integral performances on design and offdesign conditions is performing throughout all design process. This gives full interaction between user and system for immediate correction and enhancement of current design data using various optimization capabilities to feel the impact of changes on each design step. Integrated system AxSTREAM significantly shortening the design cycle time from initial machine concept to finalized design with all offdesign performances details. The design process is demonstrated for a 25kW radial inflow gas turbine. Keywords:- Radial Inflow Turbine, Performance Maps, AxSTREAM I.

Samip Shah; Gaurang Chaudhri; Digvijay Kulshreshtha; S. A. Channiwalla

434

Electric machine and current source inverter drive system  

SciTech Connect (OSTI)

A drive system includes an electric machine and a current source inverter (CSI). This integration of an electric machine and an inverter uses the machine's field excitation coil for not only flux generation in the machine but also for the CSI inductor. This integration of the two technologies, namely the U machine motor and the CSI, opens a new chapter for the component function integration instead of the traditional integration by simply placing separate machine and inverter components in the same housing. Elimination of the CSI inductor adds to the CSI volumetric reduction of the capacitors and the elimination of PMs for the motor further improve the drive system cost, weight, and volume.

Hsu, John S

2014-06-24T23:59:59.000Z

435

Turbine set with a generator feeding a network of constant frequency  

SciTech Connect (OSTI)

In a turbine set with an axial flow which is traversed by water and which is coupled to a generator feeding a network of constant frequency, the flow turbine is a propeller turbine with nonadjustable blades. The stator winding of the generator is connected to the network by means of a frequency-controllable converter, in particular a direct converter. The speed of rotation of the turbine set is controllable continuously according to the power to be delivered. In the case of an asynchronous design of the generator, it is advisable to provide the stator with a waterproof jacket on the inside and to flange it into the turbine tube, since the rotor with its cage winding is swept by water.

Spirk, F.

1983-01-11T23:59:59.000Z

436

A hypothetical profile of ordinary steam turbines with reduced cost and enhanced reliability for contemporary conditions  

SciTech Connect (OSTI)

Power steam turbines should be characterized with the reduced cost and enhanced reliability and designed on the basis of experience in steam turbine design and operation accumulated in the world`s practice for the latest years. Currently, such turbines have to be particularly matched with requirements of operation for deregulated power systems; so they should be capable of operating in both base-load and cycling modes. It seems reasonable to have such turbines with the single capacity about 250--400 MW, supercritical main steam pressure, and single steam reheat. This makes it possible to design such turbines with the minimum specific metal amount and length, with the integrated HP-IP and one two-flow LP cylinders. With existing ferritic and martensitic-class steels, the main and reheat steam temperatures can be chosen at the level of 565--580 C (1050--1075 F) without remarkable supplemental expenditures and a sacrifice of reliability. To reduce the capital cost and simplify operation and maintenance, the turbine`s regenerative system can be designed deaeratorless with motor-driven boiler-feed pumps. Such turbines could be used to replace existing old turbines with minimum expenditures. They can also be combined with large high-temperature gas-turbine sets to shape highly efficient combined-cycle units. There exist various design and technological decisions to enhance the turbine reliability and efficiency; they are well worked up and verified in long-term operation practice of different countries. For reliable and efficient operation, the turbine should be furnished with advanced automatic and automated control, diagnostic monitoring, and informative support for the operational personnel.

Leyzerovich, A.S. [Actinium Corp., St. Louis, MO (United States)

1998-12-31T23:59:59.000Z

437

Steam Path Audits on Industrial Steam Turbines  

E-Print Network [OSTI]

steam Path Audits on Industrial steam Turbines DOUGLAS R. MITCHELL. ENGINEER. ENCOTECH, INC., SCHENECTADY, NEW YORK ABSTRACT The electric utility industry has benefitted from steam path audits on steam turbines for several years. Benefits... not extend the turbine outage. To assure that all of the turbine audit data are available, the audit engineer must be at the turbine site the day the steam path is first exposed. A report of the opening audit findings is generated to describe the as...

Mitchell, D. R.

438

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

SciTech Connect (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

439

An experimental and numerical study of wind turbine seismic behavior  

E-Print Network [OSTI]

3.2.1 Description of Test Wind Turbine . . . . . .Figure 1.2: Components of a modern wind turbine . . . . . .D.3: D.4: Wind turbine parameters . . . . . . . . . . . .

Prowell, I.

2011-01-01T23:59:59.000Z

440

An experimental and numerical study of wind turbine seismic behavior  

E-Print Network [OSTI]

and Scope Wind energy is growing and turbines are regularlyfor Design of Wind Turbines. Wind Energy Department of Risloads on wind turbines. European Wind Energy Conference

Prowell, I.

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "turbine controllers inverters" 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

axis wind turbine: Topics by E-print Network  

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

to note that these views Firestone, Jeremy 65 WIND TURBINE SITING IN AN URBAN ENVIRONMENT: THE HULL, MA 660 KW TURBINE Renewable Energy Websites Summary: 1 WIND TURBINE...

442

An experimental and numerical study of wind turbine seismic behavior  

E-Print Network [OSTI]

a steel 1-MW wind turbine tower. Engineering Structures,testing of a steel wind turbine tower. Proceedings of theanalysis of steel wind turbine towers in the canadian

Prowell, I.

2011-01-01T23:59:59.000Z

443

Development of a low swirl injector concept for gas turbines  

E-Print Network [OSTI]

Injector Concept for Gas Turbines Robert K. Cheng * , Scottconcept for ultra- low NO x gas turbines. Low-swirl flamevirtually every industrial gas turbine manufacturer to meet

Cheng, R.K.; Fable, S.A.; Schmidt, D.; Arellano, L.; Smith, K.O.

2000-01-01T23:59:59.000Z

444

Shaken, not stirred: The recipe for a fish-friendly turbine  

SciTech Connect (OSTI)

It is generally agreed that injuries and mortalities among turbine-passed fish can result from several mechanisms, including rapid and extreme water pressure changes, cavitation, shear, turbulence, and mechanical injuries (strike and grinding). Advances in the instrumentation available for monitoring hydraulic conditions and Computational Fluid Dynamics (CFD) techniques now make it possible both to estimate accurately the levels of these potential injury mechanisms in operating turbines and to predict the levels in new turbine designs. This knowledge can be used to {open_quotes}design-out{close_quotes} the most significant injury mechanisms in the next generation of turbines. However, further improvements in turbine design are limited by a poor understanding of the levels of mechanical and hydraulic stresses that can be tolerated by turbine-passed fish. The turbine designers need numbers (biological criteria) that define a safety zone for fish within which pressures, shear forces, cavitation, and chance of mechanical strike are all at acceptable levels for survival. This paper presents the results of a literature review of fish responses to the types of biological stresses associated with turbine passage, as studied separately under controlled conditions in the laboratory rather than in combination at field sites. Some of the controlled laboratory and field studies reviewed here were bioassays carried out for reasons unrelated to hydropower production. Analysis of this literature was used to develop provisional biological criteria for hydroelectric turbine designers. These biological criteria have been utilized in the U.S. Department of Energy`s Advanced Hydropower Turbine System (AHTS) Program to evaluate the results of conceptual engineering designs and the potential value of future turbine models and prototypes.

Cada, G.F.

1997-03-01T23:59:59.000Z

445

Inverted Metamorphic Multijunction (IMM) Cell Processing Instructions  

SciTech Connect (OSTI)

This technical report details the processing schedule used to fabricate Inverted Metamorphic Multijunction (IMM) concentrator solar cells at The National Renewable Energy Laboratory (NREL). These devices are used as experimental test structures to support the research at NREL that is focused on increasing the efficiency of photovoltaic power conversion. They are not intended to be devices suitable for deployment in working concentrator systems primarily because of heat sinking issues. The process schedule was developed to be compatible with small sample sizes and to afford relatively rapid turn-around times, in support of research efforts. The report describes the use of electro deposition of gold for both the back and front contacts. Electro-deposition is used because of its rapid turn around time and because it is a benign metallization technique that is seldom responsible for damage to the semiconductors. The layer transfer technique is detailed including the use of a commercially available adhesive and the etching away of the parent gallium arsenide substrate. Photolithography is used to define front contact grids as well as the mesa area of the cell. Finally, the selective wet chemical etchant system is introduced and its use to reveal the back contact is described.

Duda, A.; Ward, S.; Young, M.

2012-02-01T23:59:59.000Z

446

Turbine blade cooling  

DOE Patents [OSTI]

A turbine rotor blade comprises a shank portion, a tip portion and an airfoil. The airfoil has a pressure side wall and a suction side wall that are interconnected by a plurality of partition sidewalls, defining an internal cooling passageway within the airfoil. The internal cooling passageway includes at least one radial outflow passageway to direct a cooling medium flow from the shank portion towards the tip portion and at least one radial inflow passageway to direct a cooling medium flow from the tip portion towards the shank portion. A number of mixing ribs are disposed on the partition sidewalls within the radial outflow passageways so as to enhance the thermal mixing of the cooling medium flow, thereby producing improved heat transfer over a broad range of the Buoyancy number.

Staub, Fred Wolf (Schenectady, NY); Willett, Fred Thomas (Niskayuna, NY)

2000-01-01T23:59:59.000Z

447

Turbine blade cooling  

DOE Patents [OSTI]

A turbine rotor blade comprises a shank portion, a tip portion and an airfoil. The airfoil has a pressure side wall and a suction side wall that are interconnected by a plurality of partition sidewalls, defining an internal cooling passageway within the airfoil. The internal cooling passageway includes at least one radial outflow passageway to direct a cooling medium flow from the shank portion towards the tip portion and at least one radial inflow passageway to direct a cooling medium flow from the tip portion towards the shank portion. A number of mixing ribs are disposed on the partition sidewalls within the radial outflow passageways so as to enhance the thermal mixing of the cooling medium flow, thereby producing improved heat transfer over a broad range of the Buoyancy number.

Staub, Fred Wolf (Schenectady, NY); Willett, Fred Thomas (Niskayuna, NY)

1999-07-20T23:59:59.000Z

448

Wind turbine rotor aileron  

DOE Patents [OSTI]

A wind turbine has a rotor with at least one blade which has an aileron which is adjusted by an actuator. A hinge has two portions, one for mounting a stationary hinge arm to the blade, the other for coupling to the aileron actuator. Several types of hinges can be used, along with different actuators. The aileron is designed so that it has a constant chord with a number of identical sub-assemblies. The leading edge of the aileron has at least one curved portion so that the aileron does not vent over a certain range of angles, but vents if the position is outside the range. A cyclic actuator can be mounted to the aileron to adjust the position periodically. Generally, the aileron will be adjusted over a range related to the rotational position of the blade. A method for operating the cyclic assembly is also described.

Coleman, Clint (Warren, VT); Kurth, William T. (Warren, VT)

1994-06-14T23:59:59.000Z

449

Turbine blade cooling  

DOE Patents [OSTI]

A turbine rotor blade comprises a shank portion, a tip portion and an airfoil. The airfoil has a pressure side wall and a suction side wall that are interconnected by a plurality of partition sidewalls, defining an internal cooling passageway within the airfoil. The internal cooling passageway includes at least one radial outflow passageway to direct a cooling medium flow from the shank portion towards the tip portion and at least one radial inflow passageway to direct a cooling medium flow from the tip portion towards the shank portion. A number of mixing ribs are disposed on the partition sidewalls within the radial outflow passageways so as to enhance the thermal mixing of the cooling medium flow, thereby producing improved heat transfer over a broad range of the Buoyancy number. 13 figs.

Staub, F.W.; Willett, F.T.

1999-07-20T23:59:59.000Z

450

Sprayed skin turbine component  

DOE Patents [OSTI]

Fabricating a turbine component (50) by casting a core structure (30), forming an array of pits (24) in an outer surface (32) of the core structure, depositing a transient liquid phase (TLP) material (40) on the outer surface of the core structure, the TLP containing a melting-point depressant, depositing a skin (42) on the outer surface of the core structure over the TLP material, and heating the assembly, thus forming both a diffusion bond and a mechanical interlock between the skin and the core structure. The heating diffuses the melting-point depressant away from the interface. Subsurface cooling channels (35) may be formed by forming grooves (34) in the outer surface of the core structure, filling the grooves with a fugitive filler (36), depositing and bonding the skin (42), then removing the fugitive material.

Allen, David B

2013-06-04T23:59:59.000Z

451

Multiple piece turbine blade  

DOE Patents [OSTI]

A turbine rotor blade with a spar and shell construction, the spar including an internal cooling supply channel extending from an inlet end on a root section and ending near the tip end, and a plurality of external cooling channels formed on both side of the spar, where a middle external cooling channel is connected to the internal cooling supply channels through a row of holes located at a middle section of the channels. The spar and the shell are held together by hooks that define serpentine flow passages for the cooling air and include an upper serpentine flow circuit and a lower serpentine flow circuit. the serpentine flow circuits all discharge into a leading edge passage or a trailing edge passage.

Kimmel, Keith D (Jupiter, FL)

2012-05-29T23:59:59.000Z

452

Development of a high-efficiency solar micro-inverter  

E-Print Network [OSTI]

In typical solar power installations, multiple modules are connected to the grid through a single high-power inverter. However, an alternative approach is to connect each solar module directly to the grid through a ...

Hayman, Alexander Khaled

2009-01-01T23:59:59.000Z

453

Series Resonant Inverter with Contactless Transformers for Multiple LED Lamps.  

E-Print Network [OSTI]

??A half-bridge series-resonant inverter adopted to realize the quasi current source and the constant current source with a number of contactless transformers in series for (more)

Cheng, Shuen-Wen

2013-01-01T23:59:59.000Z

454

Project Invert WP6 Case Studies Case studies  

E-Print Network [OSTI]

, Greece · FEWE ­ Polish Foundation for Energy Efficiency, Poland · FhG-ISI ­ Fraunhofer Institute for Systems and Innovation Research, Germany Contact/Information: web-site: www.invert.at or directly

455

A semi-invertible operator Oseledets theorem Cecilia Gonzalez-Tokman  

E-Print Network [OSTI]

A semi-invertible operator Oseledets theorem Cecilia Gonz´alez-Tokman Anthony Quas October 15, 2011 Abstract Semi-invertible multiplicative ergodic theorems establish the existence of an Oseledets splitting for cocycles of non-invertible linear operators (such as transfer operators) over an invertible

Quas, Anthony

456

A Five-Level Three-Phase Hybrid Cascade Multilevel Inverter Using a Single DC Source  

E-Print Network [OSTI]

A Five-Level Three-Phase Hybrid Cascade Multilevel Inverter Using a Single DC Source for a PM to construct a 3-phase 5-level cascade multilevel inverter to be used as a drive for a PM traction motor. The 5-level inverter consists of a standard 3-leg inverter (one leg for each phase) and an H-bridge in series

Tolbert, Leon M.

457

INVERTIBILITY IN INFINITE-DIMENSIONAL SPACES CHIA-CHUAN TSENG AND NGAI-CHING WONG  

E-Print Network [OSTI]

INVERTIBILITY IN INFINITE-DIMENSIONAL SPACES CHIA-CHUAN TSENG AND NGAI-CHING WONG Abstract. An interesting result of Doyle and Hocking states that a topological n-manifold is invertible if and only is invertible. We shall also discuss the invertibility of other infinite-dimensional objects as well

Wong, Ngai-Ching

458

Some Classes of Invertible Matrices in GF(2) James S. Plank  

E-Print Network [OSTI]

Some Classes of Invertible Matrices in GF(2) James S. Plank Adam L. Buchsbaum Technical Report UT Invertible matrices in GF(2) are important for constructing MDS erasure codes. This paper proves that certain classes of matrices in GF(2) are invertible, plus some additional properties about invertible matrices. 1

Plank, Jim

459

INVERTIBLE FILTER BANKS ON THE 2-SPHERE B.T. Thomas Yeo Wanmei Ou Polina Golland  

E-Print Network [OSTI]

INVERTIBLE FILTER BANKS ON THE 2-SPHERE B.T. Thomas Yeo Wanmei Ou Polina Golland Computer Science to the sphere, many key challenges remain. In this paper, we develop conditions for the invertibility be incorpo- rated into the design of self-invertible axis-symmetric wavelets. Self- invertibility

Golland, Polina

460

Performance Analysis of a Hybrid Asymmetric Multilevel Inverter for High Voltage Active Power Filter Applications  

E-Print Network [OSTI]

Performance Analysis of a Hybrid Asymmetric Multilevel Inverter for High Voltage Active Power voltage-source inverters connected in series (known as cascaded hybrid asymmetric multilevel inverter scheme is developed to allow the operation of the inverter modules at different voltages and switching

Catholic University of Chile (Universidad Católica de Chile)

Note: This page contains sample records for the topic "turbine controllers inverters" 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

SERI advanced wind turbine blades  

SciTech Connect (OSTI)

The primary goal of the Solar Energy Research Institute`s (SERI) advanced wind turbine blades is to convert the kinetic energy in the wind into mechanical energy in an inexpensive and efficient manner. To accomplish this goal, advanced wind turbine blades have been developed by SERI that utilize unique airfoil technology. Performance characteristics of the advanced blades were verified through atmospheric testing on fixed-pitch, stall-regulated horizontal-axis wind turbines (HAWTs). Of the various wind turbine configurations, the stall-regulated HAWT dominates the market because of its simplicity and low cost. Results of the atmospheric tests show that the SERI advanced blades produce 10% to 30% more energy than conventional blades. 6 refs.

Tangler, J.; Smith, B.; Jager, D.

1992-02-01T23:59:59.000Z

462

SERI advanced wind turbine blades  

SciTech Connect (OSTI)

The primary goal of the Solar Energy Research Institute's (SERI) advanced wind turbine blades is to convert the kinetic energy in the wind into mechanical energy in an inexpensive and efficient manner. To accomplish this goal, advanced wind turbine blades have been developed by SERI that utilize unique airfoil technology. Performance characteristics of the advanced blades were verified through atmospheric testing on fixed-pitch, stall-regulated horizontal-axis wind turbines (HAWTs). Of the various wind turbine configurations, the stall-regulated HAWT dominates the market because of its simplicity and low cost. Results of the atmospheric tests show that the SERI advanced blades produce 10% to 30% more energy than conventional blades. 6 refs.

Tangler, J.; Smith, B.; Jager, D.

1992-02-01T23:59:59.000Z

463

Reduced Turbine Emissions Using Hydrogen-Enriched Fuels  

E-Print Network [OSTI]

optimal use of fuel lean combustion for NOx control ­ Replaces hydrocarbon fuels for reduced CO2 emissions ­ Enables use of domestically-produced H2 #12;U.S. CO2 EmissionsU.S. CO2 Emissions by Combustion Source 0 81Reduced Turbine Emissions Using Hydrogen-Enriched Fuels Robert W. Schefer Joseph C. Oefelein Jay O

464

InVERT molding for scalable control of tissue microarchitecture  

E-Print Network [OSTI]

Complex tissues contain multiple cell types that are hierarchically organized within morphologically and functionally distinct compartments. Construction of engineered tissues with optimized tissue architecture has been ...

Ungrin, M. D.

465

Integrated Inverter Control for Multiple Electric Machines - Energy  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation ProposedUsingFunInfrared Land Surface EmissivityInstrillmentDOE/CE-0180ResearchInnovation

466

Vertical axis wind turbine acoustics  

E-Print Network [OSTI]

Vertical Axis Wind Turbine Acoustics Charlie Pearson Corpus Christi College Cambridge University Engineering Department A thesis submitted for the degree of Doctor of Philosophy September 2013 Declaration Described in this dissertation is work... quickly to changing wind conditions, small- scale vertical axis wind turbines (VAWTs) have been proposed as an efficient solution for deployment in built up areas, where the wind is more gusty in nature. If VAWTs are erected in built up areas...

Pearson, Charlie

2014-04-08T23:59:59.000Z

467

High temperature turbine engine structure  

DOE Patents [OSTI]

A high temperature ceramic/metallic turbine engine includes a metallic housing which journals a rotor member of the turbine engine. A ceramic disk-like shroud portion of the engine is supported on the metallic housing portion and maintains a close running clearance with the rotor member. A ceramic spacer assembly maintains the close running clearance of the shroud portion and rotor member despite differential thermal movements between the shroud portion and metallic housing portion.

Carruthers, William D. (Mesa, AZ); Boyd, Gary L. (Tempe, AZ)

1993-01-01T23:59:59.000Z

468

High temperature turbine engine structure  

DOE Patents [OSTI]

A high temperature ceramic/metallic turbine engine includes a metallic housing which journals a rotor member of the turbine engine. A ceramic disk-like shroud portion of the engine is supported on the metallic housing portion and maintains a close running clearance with the rotor member. A ceramic spacer assembly maintains the close running clearance of the shroud portion and rotor member despite differential thermal movements between the shroud portion and metallic housing portion.

Carruthers, William D. (Mesa, AZ); Boyd, Gary L. (Tempe, AZ)

1992-01-01T23:59:59.000Z

469

High temperature turbine engine structure  

DOE Patents [OSTI]

A high temperature ceramic/metallic turbine engine includes a metallic housing which journals a rotor member of the turbine engine. A ceramic disk-like shroud portion of the engine is supported on the metallic housing portion and maintains a close running clearance with the rotor member. A ceramic spacer assembly maintains the close running clearance of the shroud portion and rotor member despite differential thermal movements between the shroud portion and metallic housing portion.

Carruthers, William D. (Mesa, AZ); Boyd, Gary L. (Tempe, AZ)

1994-01-01T23:59:59.000Z

470

Rim seal for turbine wheel  

DOE Patents [OSTI]

A turbine wheel assembly includes a disk having a plurality of blades therearound. A ceramic ring is mounted to the housing of the turbine wheel assembly. A labyrinth rim seal mounted on the disk cooperates with the ceramic ring to seal the hot gases acting on the blades from the disk. The ceramic ring permits a tighter clearance between the labyrinth rim seal and the ceramic ring.

Glezer, Boris (Del Mar, CA); Boyd, Gary L. (Alpine, CA); Norton, Paul F. (San Diego, CA)

1996-01-01T23:59:59.000Z

471

2.3-MW Medium-Voltage, Three-Level Wind Energy Inverter Applying a Unique Bus Structure and 4.5-kV Si/SiC Hybrid Isolated Power Modules: Preprint  

SciTech Connect (OSTI)

A high-efficiency, 2.3-MW, medium-voltage, three-level inverter utilizing 4.5-kV Si/SiC (silicon carbide) hybrid modules for wind energy applications is discussed. The inverter addresses recent trends in siting the inverter within the base of multimegawatt turbine towers. A simplified split, three-layer laminated bus structure that maintains low parasitic inductances is introduced along with a low-voltage, high-current test method for determining these inductances. Feed-thru bushings, edge fill methods, and other design features of the laminated bus structure provide voltage isolation that is consistent with the 10.4-kV module isolation levels. Inverter efficiency improvement is a result of the (essential) elimination of the reverse recovery charge present in 4.5-kV Si PIN diodes, which can produce a significant reduction in diode turn-off losses as well as insulated-gate bipolar transistor (IGBT) turn-on losses. The hybrid modules are supplied in industry-standard 140 mm x 130 mm and 190 mm x 130 mm packages to demonstrate direct module substitution into existing inverter designs. A focus on laminated bus/capacitor-bank/module subassembly level switching performance is presented.

Erdman, W.; Keller, J.; Grider, D.; VanBrunt, E.

2014-11-01T23:59:59.000Z

472

Definition of a 5-MW Reference Wind Turbine for Offshore System Development  

SciTech Connect (OSTI)

This report describes a three-bladed, upwind, variable-speed, variable blade-pitch-to-feather-controlled multimegawatt wind turbine model developed by NREL to support concept studies aimed at assessing offshore wind technology.

Jonkman, J.; Butterfield, S.; Musial, W.; Scott, G.

2009-02-01T23:59:59.000Z

473

Torque ripple in a Darrieus, vertical axis wind turbine  

SciTech Connect (OSTI)

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

Reuter, R.C. Jr.

1980-09-01T23:59:59.000Z

474

Sensorless Control of Doubly-Fed Induction Generator-Based Wind urbines using a High-Order Sliding Mode Observer  

E-Print Network [OSTI]

­ This paper deals with the sensorless control of a doubly-fed induction generator based wind turbine of the proposed sensorless control strategy. Keywords: Wind turbine, doubly-fed induction generator, sensorless scheme for a grid-connected wind turbine is given in Fig. 2. The wind turbine modeling is inspired from

Brest, Université de

475

Cooling/heating augmentation during turbine startup/shutdown using a seal positioned by thermal response of turbine parts and consequent relative movement thereof  

DOE Patents [OSTI]

In a turbine rotor, a thermal mismatch between various component parts of the rotor occurs particularly during transient operations such as shutdown and startup. A thermal medium flows past and heats or cools one part of the turbine which may have a deleterious thermal mismatch with another part. By passively controlling the flow of cooling medium past the one part in response to relative movement of thermally responsive parts of the turbine, the flow of thermal medium along the flow path can be regulated to increase or reduce the flow, thereby to regulate the temperature of the one part to maintain the thermal mismatch within predetermined limits.

Schmidt, Mark Christopher (Niskayuna, NY)

2000-01-01T23:59:59.000Z

476

Virtual Models for Prediction of Wind Turbine Parameters  

E-Print Network [OSTI]

AbstractIn this paper, a data-driven methodology for the development of virtual models of a wind turbine is presented. To demonstrate the proposed methodology, two parameters of the wind turbine have been selected for modeling, namely, power output and rotor speed. A virtual model for each of the two parameters is developed and tested with data collected at a wind farm. Both models consider controllable and noncontrollable parameters of the wind turbine, as well as the delay effect of wind speed and other parameters. To mitigate data bias of each virtual model and ensure its robustness, a training set is assembled from ten randomly selected turbines. The performance of a virtual model is largely determined by the input parameters selected and the data mining algorithms used to extract the model. Several data mining algorithms for parameter selection and model extraction are analyzed. The research presented in the paper is illustrated with computational results. Index TermsData mining, parameter selection, power prediction, virtual model, wind turbine. I.

Andrew Kusiak

477

Warming systems prolong steam-turbine life, accelerate startup  

SciTech Connect (OSTI)

Cycling capability is one of the top challenges in the design, operation, and maintenance of today's powerplants. This article describes how permanent warming systems can be a powerful ally in meeting this challenge, particularly for aging steam turbines. The warming system is typically used to hold steam-turbine shell temperatures during short shutdowns (up to about three days), or to pre-warm shells after longer shut-downs. Permanent warming systems elevate metal temperature above 500 F, distinguishing them from heat tracing systems that operate at much lower temperatures for freeze protection or viscosity control. Permanent warming systems can reduced steam-turbine damage during both startup heating and off-line cooling, and can reduce plant startup time.

Swanekamp, R.

1994-08-01T23:59:59.000Z

478

Quiet airfoils for small and large wind turbines  

DOE Patents [OSTI]

Thick airfoil families with desirable aerodynamic performance with minimal airfoil induced noise. The airfoil families are suitable for a variety of wind turbine designs and are particularly well-suited for use with horizontal axis wind turbines (HAWTs) with constant or variable speed using pitch and/or stall control. In exemplary embodiments, a first family of three thick airfoils is provided for use with small wind turbines and second family of three thick airfoils is provided for use with very large machines, e.g., an airfoil defined for each of three blade radial stations or blade portions defined along the length of a blade. Each of the families is designed to provide a high maximum lift coefficient or high lift, to exhibit docile stalls, to be relatively insensitive to roughness, and to achieve a low profile drag.

Tangler, James L. (Boulder, CO); Somers, Dan L. (Port Matilda, PA)

2012-06-12T23:59:59.000Z

479

An experimental and numerical study of wind turbine seismic behavior  

E-Print Network [OSTI]

studied were vertical axis wind turbines, which are nottesting of vertical axis wind turbines (VAWT). For example,vertical axis turbines (VAWTs). Gradually, as the industry matured, most design concepts standardized on horizontal axis wind turbines (

Prowell, I.

2011-01-01T23:59:59.000Z

480

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

SciTech Connect (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

Note: This page contains sample records for the topic "turbine controllers inverters" 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

Advanced Turbine Systems Program -- Conceptual design and product development. Quarterly report, August 1--October 31, 1995  

SciTech Connect (OSTI)

The objective of Phase 2 of the Advanced Turbine Systems (ATS) Program is to provide the conceptual design and product development plan for an ultra high efficiency, environmentally superior and cost competitive industrial gas turbine system to be commercialized by the year 2000. A secondary objective is to begin early development of technologies critical to the success of ATS. This quarterly report, addresses only Task 4, conversion of a gas turbine to a coal-fired gas turbine, which was completed during the quarter and the nine subtasks included in Task 8, design and test of critical components. These nine subtasks address six ATS technologies as follows: catalytic combustion; recuperator; autothermal fuel reformer; high temperature turbine disc; advanced control system (MMI); and ceramic materials.

NONE

1995-12-31T23:59:59.000Z

482

Internal combustion engine system having a power turbine with a broad efficiency range  

DOE Patents [OSTI]

An engine system incorporating an air breathing, reciprocating internal combustion engine having an inlet for air and an exhaust for products of combustion. A centripetal turbine receives products of the combustion and has a housing in which a turbine wheel is rotatable. The housing has first and second passages leading from the inlet to discrete, approximately 180.degree., portions of the circumference of the turbine wheel. The passages have fixed vanes adjacent the periphery of the turbine wheel and the angle of the vanes in one of the passages is different than those in the other so as to accommodate different power levels providing optimum approach angles between the gases passing the vanes and the blades of the turbine wheel. Flow through the passages is controlled by a flapper valve to direct it to one or the other or both passages depending upon the load factor for the engine.

Whiting, Todd Mathew; Vuk, Carl Thomas

2010-04-13T23:59:59.000Z

483

Advanced Turbine Systems program conceptual design and product development. Quarterly report, February--April 1994  

SciTech Connect (OSTI)

Task 8.5 (active clearance control) was replaced with a test of the 2600F prototype turbine (Task 8.1T). Test 8.1B (Build/Teardown of prototype turbine) was added. Tasks 4 (conversion of gas-fired turbine to coal-fired turbine) and 5 (market study) were kicked off in February. Task 6 (conceptual design) was also initiated. Task 8.1 (advanced cooling technology) now has an approved test plan. Task 8.4 (ultra low NOx combustion technology) has completed the code development and background gathering phase. Task 8.6 (two-phase cooling of turbine vanes) is proceeding well; initial estimates indicate that nearly 2/3 of required cooling flow can be eliminated.

NONE

1995-02-01T23:59:59.000Z

484

Subhourly wind forecasting techniques for wind turbine operations  

SciTech Connect (OSTI)

Three models for making automated forecasts of subhourly wind and wind power fluctuations were examined to determine the models' appropriateness, accuracy, and reliability in wind forecasting for wind turbine operation. Such automated forecasts appear to have value not only in wind turbine control and operating strategies, but also in improving individual wind turbine control and operating strategies, but also in improving individual wind turbine operating strategies (such as determining when to attempt startup). A simple persistence model, an autoregressive model, and a generalized equivalent Markhov (GEM) model were developed and tested using spring season data from the WKY television tower located near Oklahoma City, Oklahoma. The three models represent a pure measurement approach, a pure statistical method and a statistical-dynamical model, respectively. Forecasting models of wind speed means and measures of deviations about the mean were developed and tested for all three forecasting techniques for the 45-meter level and for the 10-, 30- and 60-minute time intervals. The results of this exploratory study indicate that a persistence-based approach, using onsite measurements, will probably be superior in the 10-minute time frame. The GEM model appears to have the most potential in 30-minute and longer time frames, particularly when forecasting wind speed fluctuations. However, several improvements to the GEM model are suggested. In comparison to the other models, the autoregressive model performed poorly at all time frames; but, it is recommended that this model be upgraded to an autoregressive moving average (ARMA or ARIMA) model. The primary constraint in adapting the forecasting models to the production of wind turbine cluster power output forecasts is the lack of either actual data, or suitable models, for simulating wind turbine cluster performance.

Wegley, H.L.; Kosorok, M.R.; Formica, W.J.

1984-08-01T23:59:59.000Z

485

Math 28S Invertibility Criteria Fall 2011 Various criteria which are equivalent to a matrix being invertible are at the heart of linear alge-  

E-Print Network [OSTI]

Math 28S Invertibility Criteria Fall 2011 Various criteria which are equivalent to a matrix being invertible are at the heart of linear alge- bra, because they combine all the ideas from the subject. A is invertible; 3. {a} is linearly independent; 4. {a} spans F; 5. {a} is a basis for F. Theorem 2 Let A = a b c

McClendon, David M.

486

IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS, VOL. 57, NO. 8, AUGUST 2010 2761 Cascaded Nine-Level Inverter for Hybrid-Series  

E-Print Network [OSTI]

-Level Inverter for Hybrid-Series Active Power Filter, Using Industrial Controller Alexander Varschavsky, Juan of this new application. Index Terms--Active filters, harmonic distortion, multilevel systems, power quality nine-level active power filter (APF). The controller is now able to make all required tasks

Catholic University of Chile (Universidad Católica de Chile)

487

Three-Phase Modular Cascaded H-Bridge Multilevel Inverter with Individual MPPT for Grid-Connected Photovoltaic Systems  

SciTech Connect (OSTI)

A three-phase modular cascaded H-bridge multilevel inverter for a grid-connected photovoltaic (PV) system is presented in this paper. To maximize the solar energy extraction of each PV string, an individual maximum power point tracking (MPPT) control scheme is applied, which allows the independent control of each dc-link voltage. PV mismatches may introduce unbalanced power supplied to the three-phase system. To solve this issue, a control scheme with modulation compensation is proposed. The three-phase modular cascaded multilevel inverter prototype has been built. Each H-bridge is connected to a 185 W solar panel. Simulation and experimental results are presented to validate the proposed ideas.

Xiao, Bailu [ORNL; Hang, Lijun [ORNL; Riley, Cameron [University of Tennessee, Knoxville (UTK); Tolbert, Leon M [ORNL; Ozpineci, Burak [ORNL

2013-01-01T23:59:59.000Z

488

Airfoils for wind turbine  

DOE Patents [OSTI]

Airfoils for the tip and mid-span regions of a wind turbine blade have upper surface and lower surface shapes and contours between a leading edge and a trailing edge that minimize roughness effects of the airfoil and provide maximum lift coefficients that are largely insensitive to roughness effects. The airfoil in one embodiment is shaped and contoured to have a thickness in a range of about fourteen to seventeen percent, a Reynolds number in a range of about 1,500,000 to 2,000,000, and a maximum lift coefficient in a range of about 1.4 to 1.5. In another embodiment, the airfoil is shaped and contoured to have a thickness in a range of about fourteen percent to sixteen percent, a Reynolds number in a range of about 1,500,000 to 3,000,000, and a maximum lift coefficient in a range of about 0.7 to 1.5. Another embodiment of the airfoil is shaped and contoured to have a Reynolds in a range of about 1,500,000 to 4,000,000, and a maximum lift coefficient in a range of about 1.0 to 1.5.

Tangler, James L. (Boulder, CO); Somers, Dan M. (State College, PA)

2000-01-01T23:59:59.000Z

489

Introduction to the model-free control of microgrids  

E-Print Network [OSTI]

This letter presents the application of the model-free control approach to the microgrid control. We show in simulation that the method allows to control, with a simple controller, voltage, current and power of inverter-based microgrids.

Michel, Loc

2011-01-01T23:59:59.000Z

490

MEASURING IMPACTS TO BIRDS CAUSED BY WIND TURBINES MEASURING IMPACTS TO BIRDS CAUSED BY WIND TURBINES  

E-Print Network [OSTI]

APPENDIX A MEASURING IMPACTS TO BIRDS CAUSED BY WIND TURBINES #12;A-1 APPENDIX A MEASURING IMPACTS TO BIRDS CAUSED BY WIND TURBINES 1.0 INTRODUCTION Differential composition of wind turbines at wind energy used is the number of fatalities per wind turbine per year (Anderson et al. 1999). This metric has

491

WIND TURBINE SITING IN AN URBAN ENVIRONMENT: THE HULL, MA 660 KW TURBINE  

E-Print Network [OSTI]

1 WIND TURBINE SITING IN AN URBAN ENVIRONMENT: THE HULL, MA 660 KW TURBINE J. F. Manwell, J. G. Mc turbine at Windmill Point in Hull, Massachusetts represents a high point in the long history of wind, through the installation of a 40 kW Enertech machine in the 1980's to the installation of the new turbine

Massachusetts at Amherst, University of

492

Sandia National Laboratories: wind-turbine rotor design  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administrationcontroller systems controller systems Scaled Windwhite LEDwind turbines

493

Efficiency consideration of DC link soft-switching inverters for motor drive applications  

SciTech Connect (OSTI)

This paper critically evaluates efficiency of soft switching inverters including an actively clamped resonant dc link inverter and a clamped-mode resonant pole inverter. An analytical approach to evaluating efficiency of the clamped-mode soft switching inverter has been developed. The evaluation results are compared with that of the standard pulse-width-modulation (PWM) inverter. A 50-kW induction motor is used as the variable load, and the inverter efficiency is evaluated under different speed and torque conditions. The clamped-mode soft-switching inverter, although eliminating the switching loss, shows poor efficiency over the entire load range. Under low load conditions, the efficiency profile is even worse. The actively clamped resonant dc link inverter shows highest efficiency over the entire speed and torque range. However, its energy saving over the standard PWM inverter is marginal under full load or high speed conditions.

Lai, J.S.; Young, R.W.; McKeever, J.W.

1994-12-31T23:59:59.000Z

494

Parametric design of floating wind turbines  

E-Print Network [OSTI]

As the price of energy increases and wind turbine technology matures, it is evident that cost effective designs for floating wind turbines are needed. The next frontier for wind power is the ocean, yet development in near ...

Tracy, Christopher (Christopher Henry)

2007-01-01T23:59:59.000Z

495

The Inside of a Wind Turbine  

Broader source: Energy.gov [DOE]

Wind turbines harness the power of the wind and use it to generate electricity. Simply stated, a wind turbine works the opposite of a fan. Instead of using electricity to make wind, like a fan,...

496

Building the Basic PVC Wind Turbine  

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

Energy Smart CD- Building PVC Turbine 8 Some Blade Building Tips KidWind model wind turbines are designed for use in science classes, or as a hobby or science fair project....

497

Diffuser Augmented Wind Turbine Analysis Code  

E-Print Network [OSTI]

, it is necessary to develop innovative wind capturing devices that can produce energy in the locations where large conventional horizontal axis wind turbines (HAWTs) are too impractical to install and operate. A diffuser augmented wind turbine (DAWT) is one...

Carroll, Jonathan

2014-05-31T23:59:59.000Z

498

Theory and Performance of Tesla Turbines  

E-Print Network [OSTI]

gas turbines for combined heat and power. In: Ap- plied10.1115/1.4001356. [3] Combined Heat and Power. Tech. rep.of Tesla Turbines for Combined Heat and Power Applications.

Romanin, Vincent D.

2012-01-01T23:59:59.000Z

499

Rugged ATS turbines for alternate fuels  

SciTech Connect (OSTI)

A major national effort is directed to developing advanced turbine systems designed for major improvements in efficiency and emissions performance using natural gas fuels. These turbine designs are also to be adaptable for future operation with alternate coal and biomass derived fuels. For several potential alternate fuel applications, available hot gas cleanup technologies will not likely be adequate to protect the turbine flowpath from deposition and corrosion. Past tests have indicated that cooling turbine airfoil surfaces could ruggedized a high temperature turbine flowpath to alleviate deposition and corrosion. Using this specification. ATS turbine that was evaluated. The initial analyses also showed that two-phase cooling offers the most attractive method of those explored to protect a coal-fueled ATS turbine from deposition and corrosion. This paper describes ruggedization approaches, particularly to counter the extreme deposition and corrosion effects of the high inlet temperatures of ATS turbines using alternate fuels.

Wenglarz, R.A.; Nirmalan, N.V.; Daehler, T.G.

1995-02-01T23:59:59.000Z

500

Simulating Collisions for Hydrokinetic Turbines  

SciTech Connect (OSTI)

Evaluations of blade-strike on an axial-flow Marine Hydrokinetic turbine were conducted using a conventional methodology as well as an alternative modeling approach proposed in the present document. The proposed methodology integrates the following components into a Computa- tional Fluid Dynamics (CFD) model: (i) advanced eddy-resolving flow simulations, (ii) ambient turbulence based on field data, (iii) moving turbine blades in highly transient flows, and (iv) Lagrangian particles to mimic the potential fish pathways. The sensitivity of blade-strike prob- ability to the following conditions was also evaluated: (i) to the turbulent environment, (ii) to fish size and (iii) to mean stream flow velocity. The proposed methodology provided fraction of collisions and offered the capability of analyzing the causal relationships between the flow envi- ronment and resulting strikes on rotating blades. Overall, the conventional methodology largely overestimates the probability of strike, and lacks the ability to produce potential fish and aquatic biota trajectories as they interact with the rotating turbine. By using a set of experimental corre- lations of exposure-response of living fish colliding on moving blades, the occurrence, frequency and intensity of the particle collisions was next used to calculate the survival rate of fish crossing the MHK turbine. This step indicated survival rates always greater than 98%. Although the proposed CFD framework is computationally more expensive, it provides the advantage of evaluating multiple mechanisms of stress and injury of hydrokinetic turbine devices on fish.

Richmond, Marshall C.; Romero Gomez, Pedro DJ; Rakowski, Cynthia L.

2013-10-01T23:59:59.000Z