WIND ENERGY GENERATION

Transcription

1 WIND ENERGY GENERATION Modelling and Control Olimpo Anaya-Lara, University of Strathclyde, Glasgow, UK Nick Jenkins, Cardiff University, UK Janaka Ekanayake, Cardiff University, UK Phill Cartwright, Rolls-Royce plc, UK Mike Hughes, Consultant and Imperial College London, UK WWILEY A John Wiley and Sons, Ltd., Publicat on

2 Contents About the Authors Preface Acronyms and Symbols 1 Electricity Generation from Wind Energy 1.1 Wind Farms 1.2 Wind Energy-generating Systems Wind Turbines Wind Turbine Architectures 1.3 Wind Generators Compared with Conventional Power Plant Local Impacts System-wide Impacts 1.4 Grid Code Regulations for the Integration of Wind Generation References 2 Power Electronics for Wind Turbines 2.1 Soft-starter for FSIG Wind Turbines 2.2 Voltage Source Converters (VSCs) The Two-level VSC Square-wave Operation Carrier-based PWM (CB-PWM) Switching Frequency Optimal PWM (SFO-PWM) Regular and Non-regular Sampled PWM (RS-PWM and NRS-PWM) Selective Harmonic Elimination PWM (SHEM) Voltage Space Vector Switching (SV-PWM) Hysteresis Switching 2.3 Application of VSCs for Variable-speed Systems VSC with a Diode Bridge xi xv

3 vi Contents Back-to-Back VSCs 34 References 36 3 Modelling of Synchronous Generators Synchronous Generator Construction The Air-gap Magnetic Field of the Synchronous Generator Coil Representation of the Synchronous Generator Generator Equations in the dq Frame Generator Electromagnetic Torque Steady-state Operation Synchronous Generator with Damper Windings Non-reduced Order Model Reduced-order Model Control of Large Synchronous Generators Excitation Control Prime Mover Control 55 References 56 4 Fixed-speed Induction Generator (FSIG)-based Wind Turbines Induction Machine Construction Squirrel-cage Rotor Wound Rotor Steady-state Characteristics Variations in Generator Terminal Voltage FSIG Configurations for Wind Generation Two-speed Operation Variable-slip Operation Reactive Power Compensation Equipment Induction Machine Modelling FSIG Model as a Voltage Behind a Transient Reactance Dynamic Performance of FSIG Wind Turbines Small Disturbances Performance During Network Faults 73 References 76 5 Doubly Fed Induction Generator (DFIG)-based Wind Turbines Typical DFIG Configuration 77

4 Contents vii 5.2 Steady-state Characteristics Active Power Relationships in the Steady State Vector Diagram of Operating Conditions Control for Optimum Wind Power Extraction Control Strategies for a DFIG Current-mode Control (PVdq) Rotor Flux Magnitude and Angle Control Dynamic Performance Assessment Small Disturbances Performance During Network Faults 94 References 96 6 Fully Rated Converter-based (FRC) Wind Turbines FRC Synchronous Generator-based (FRC-SG) Wind Turbine Direct-driven Wind Turbine Generators Permanent Magnets Versus Electrically Excited Synchronous Generators Permanent Magnet Synchronous Generator Wind Turbine Control and Dynamic Performance Assessment FRC Induction Generator-based (FRC-IG) Wind Turbine Steady-state Performance Control of the FRC-IG Wind Turbine Performance Characteristics of the FRC-IG Wind Turbine 119 References Influence of Rotor Dynamics on Wind Turbine Operation Blade Bending Dynamics Derivation of Three-mass Model Example: 300 kw FSIG Wind Turbine Effective Two-mass Model Assessment of FSIG and DFIG Wind Turbine Performance 128 Acknowledgement 132 References Influence of Wind Farms on Network Dynamic Performance Dynamic Stability and its Assessment Dynamic Characteristics of Synchronous Generation 136

5 viii Contents 8.3 A Synchronizing Power and Damping Power Model of a Synchronous Generator Influence of Automatic Voltage Regulator on Damping Influence on Damping of Generator Operating Conditions Influence of Turbine Governor on Generator Operation Transient Stability Voltage Stability Generic Test Network Influence of Generation Type on Network Dynamic Stability Generator 2 Synchronous Generator Generator 2 FSIG-based Wind Farm Generator 2 DFIG-based Wind Farm (PVdq Control) Generator 2 DFIG-based Wind Farm (FMAC Control) Generator 2 FRC-based Wind Farm Dynamic Interaction of Wind Farms with the Network FSIG Influence on Network Damping DFIG Influence on Network Damping Influence of Wind Generation on Network Transient Performance Generator 2 Synchronous Generator Generator 2 FSIG Wind Farm Generator 2 DFIG Wind Farm Generator 2 FRC Wind Farm 165 References Power Systems Stabilizers and Network Damping Capability of Wind Farms A Power System Stabilizer for a Synchronous Generator Requirements and Function Synchronous Generator PSS and its Performance Contributions A Power System Stabilizer for a DFIG Requirements and Function DFIG-PSS and its Performance Contributions A Power System Stabilizer for an FRC Wind Farm Requirements and Functions 182

6 Contents ix FRC PSS and its Performance Contributions 186 References The Integration of Wind Farms into the Power System Reactive Power Compensation Static Var Compensator (SVC) Static Synchronous Compensator (STATCOM) STATCOM and FSIG Stability HVAC Connections HVDC Connections LCC HVDC USC HVDC Multi-terminal HVDC HVDC Transmission Opportunities and Challenges Example of the Design of a Submarine Network Beatrice Offshore Wind Farm Onshore Grid Connection Points Technical Analysis Cost Analysis Recommended Point of Connection 213 Acknowledgement 214 References Wind Turbine Control for System Contingencies Contribution of Wind Generation to Frequency Regulation Frequency Control Wind Turbine Inertia Fast Primary Response Slow Primary Response Fault Ride-through (FRT) FSIGs DFIGs FRCs VSC HVDC with FSIG Wind Farm FRC Wind Turbines Connected Via a VSC HVDC 234 References 237 Appendix A: State-Space Concepts and Models 241

7 x C ontents Appendix B: Introduction to Eigenvalues and Eigenvectors 249 Appendix C: Linearization of State Equations 255 Appendix D: Generic Network Model Parameters 259 Index 265