About the Authors xvii
Preface xix
Acknowledgments xxiii
Acronyms xxv
Symbols xxix
Part I Preliminaries
1 Basics of Wind Energy Conversion Systems (WECS) 3
1.1 Introduction 3
1.2 Wind Energy Preliminaries 5
1.3 Major Components of WECS 16
1.4 Grid Code Requirements for High-Power WECS 23
1.5 WECS Commercial Configurations 26
1.6 Power Electronics in Wind Energy Systems 33
1.7 Control of Wind Energy Systems 35
1.8 Finite Control-Set Model Predictive Control 50
1.9 Classical and Model Predictive Control of WECS 53
1.10 Concluding Remarks 58
References 58
2 Review of Generator-Converter Configurations for WECS 61
2.1 Introduction 61
2.2 Requirements for Power Converters in MW-WECS 63
2.3 Overview of Power Converters for WECS 64
2.4 Back-to-Back Connected Power Converters 68
2.5 Passive Generator-side Power Converters 76
2.6 Power Converters for Multiphase Generators 80
2.7 Power Converters without an Intermediate DC Link 85
2.8 Concluding Remarks 87
References 89
3 Overview of Digital Control Techniques 91
3.1 Introduction 91
3.2 The Past, Present, and Future of Control Platforms 93
3.3 Reference Frame Theory 95
3.4 Digital Control of Power Conversion Systems 99
3.5 Classical Control Techniques 102
3.6 Advanced Control Techniques 110
3.7 Predictive Control Techniques 112
3.8 Comparison of Digital Control Techniques 114
3.9 Concluding Remarks 115
References 116
4 Fundamentals of Model Predictive Control 117
4.1 Introduction 117
4.2 Sampled-Data Model 119
4.3 Basics of Model Predictive Control 120
4.4 Cost Function Flexibility 128
4.5 Weighting Factor Selection 134
4.6 Delay Compensation Methods 137
4.7 Extrapolation Techniques 141
4.8 Selection of Sampling Time 145
4.9 Concluding Remarks 146
References 146
Part II Modeling of Power Converters and Wind Generators
5 Modeling of Power Converters for Model Predictive Control 151
5.1 Introduction 151
5.2 Objectives for the Modeling of Power Converters 153
5.3 Notation Employed for the Modeling 154
5.4 Two-Level Voltage Source Converter 156
5.4.1 Power Circuit 156
5.4.2 Operating Modes 157
5.4.3 Model of Output AC Voltages 159
5.4.4 Model of Input DC Branch Currents 160
5.5 Extensions to 2L-VSC Modeling 161
5.5.1 Modeling of Multiphase 2L-VSC 161
5.5.2 Modeling of BTB 2L-VSC 161
5.6 Neutral-Point Clamped Converter 162
5.6.1 Power Circuit 162
5.6.2 Operating Modes 163
5.6.3 Model of Output AC Voltages 165
5.6.4 Model of Input DC Branch Currents 165
5.7 Extensions to NPC Converter Modeling 166
5.7.1 Modeling of Multilevel and Multiphase dcc 166
5.7.2 Modeling of BTB NPC Converter 167
5.8 Modeling of Other Power Converters 169
5.8.1 Three-Level Flying Capacitor Converter 169
5.8.2 Current Source Converter 170
5.8.3 Direct Matrix Converter 172
5.8.4 Indirect Matrix Converter 173
5.9 Concluding Remarks 174
References 175
6 Modeling of Wind Generators for Model Predictive Control 177
6.1 Introduction 177
6.2 Overview of Wind Generators for Variable-Speed WECS 179
6.3 Objectives for the Dynamic Modeling of Wind Generators 181
6.4 Notation Employed for the Dynamic Modeling 182
6.5 Modeling of Permanent Magnet Synchronous Generator 184
6.6 Simulation of Permanent Magnet Synchronous Generator 191
6.7 Modeling of Induction Generator 193
6.8 Simulation of Induction Generator 201
6.9 Generator Dynamic Models for Predictive Control 204
6.10 Concluding Remarks 205
References 205
7 Mapping of Continuous-Time Models to Discrete-Time Models 207
7.1 Introduction 207
7.2 Model Predictive Control of WECS 209
7.3 Correlation Between CT and DT Models 210
7.4 Overview of Discretization Methods 213
7.5 Exact Discretization by ZOH Method 215
7.6 Approximate Discretization Methods 216
7.7 Quasi-Exact Discretization Methods 222
7.8 Comparison of Discretization Methods 229
7.9 Offline Calculation of DT Parameters Using MATLAB 231
7.10 Concluding Remarks 233
References 234
Part III Control of Variable-speed WECS
8 Control of Grid-side Converters in WECS 237
8.1 Introduction 237
8.2 Configuration of GSCs in Type 3 and 4 WECS 239
8.3 Design and Control of GSC 242
8.4 Modeling of Three-Phase GSC 247
8.5 Calculation of Reference Grid-side Variables 259
8.6 Predictive Current Control of 2L-VSI in dq-Frame 262
8.7 Predictive Current Control of NPC Inverter in ??-Frame 270
8.8 Predictive Power Control of NPC Inverter with Grid-side MPPT 277
8.9 Real-Time Implementation of MPC Schemes 282
8.10 Concluding Remarks 282
References 283
9 Control of PMSG WECS with Back-to-Back Connected Converters 285
9.1 Introduction 285
9.2 Configuration of PMSG WECS with BTB Converters 287
9.3 Modeling of Permanent Magnet Synchronous Generator 289
9.4 Control of Permanent Magnet Synchronous Generator 292
9.5 Digital Control of BTB Converter-Based PMSG WECS 294
9.6 Predictive Current Control of BTB 2L-VSC-Based PMSG WECS 299
9.7 Predictive Current Control of BTB-NPC-Converter-Based PMSG Wecs 308
9.8 Predictive Torque Control of BTB 2L-VSC-Based PMSG WECS 318
9.9 Other MPC Schemes for PMSG WECS 323
9.10 Real-Time Implementation of MPC Schemes 324
9.11 Concluding Remarks 326
References 327
10 Control of PMSG WECS with Passive Generator-side Converters 329
10.1 Introduction 329
10.2 Configuration of PMSG WECS with PGS Converters 331
10.3 Modeling of the Two-Level Boost Converter 334
10.4 Modeling of the Three-Level Boost Converter 338
10.5 Digital Control of PGS Converter-Based PMSG WECS 343
10.6 Predictive Current Control of 2L-PGS-Converter-Based PMSG WECS 346
10.7 Predictive Current Control of 3L-PGS-Converter-Based PMSG WECS 349
10.8 Analysis of PMSG WECS Performance with PGS Converters 352
10.9 Other MPC Schemes for PMSG WECS 362
10.10 Real-Time Implementation of MPC Schemes 363
10.11 Concluding Remarks 365
References 366
11 Control of SCIG WECS with Voltage Source Converters 367
11.1 Introduction 367
11.2 Configuration of SCIG WECS with BTB Converters 369
11.3 Modeling of Squirrel-Cage Induction Generator 370
11.4 Control of Squirrel-Cage Induction Generator 374
11.5 Digital Control of BTB Converter-Based SCIG WECS 378
11.6 Predictive Current Control of BTB 2L-VSC-Based SCIG WECS 382
11.7 Predictive Torque Control of BTB NPC Converter-Based SCIG WECS 391
11.8 Real-Time Implementation of MPC Schemes 398
11.9 Concluding Remarks 400
References 400
12 Control of DFIG WECS with Voltage Source Converters 403
12.1 Introduction 403
12.2 Configuration of DFIG WECS and Power Flow 405
12.3 Control of Doubly Fed Induction Generator 407
12.4 Modeling of Doubly Fed Induction Generator 411
12.5 Digital Control of BTB Converter-Based DFIG WECS 417
12.6 Indirect Predictive Current Control of DFIG WECS 419
12.7 Direct Predictive Current Control of DFIG WECS 430
12.8 Concluding Remarks 435
References 436
Appendix A Turbine and Generator Parameters 437
A.1 Notation of Generator Variables 438
A.2 Base Values 439
A.3 Per-Unit Values 440
A.4 Wind Turbine Parameters 444
A.5 Three-Phase Grid Parameters 445
A.6 Permanent Magnet Synchronous Generator Parameters 446
A.7 Squirrel-Cage Induction Generator Parameters 450
A.8 Doubly Fed Induction Generator Parameters 451
Appendix B Chapter Appendices 453
B.1 Appendix for Chapter 4 453
References 454
B.2 Appendix for Chapter 5 455
Appendix C MATLAB Demo Projects 461
Index 463
