Wind Turbine Control and Monitoring (eBook)

Ningsu Luo is Professor of Control Systems Engineering at Department of Electrical Engineering, Electronics and Automatic Control, University of Girona, Spain. He obtained his PhD in Control Engineering from Southeast University in 1990 and PhD in Physics Science from University of the Basque Country in 1994, respectively. His current research activities are focused on modeling, identification and control design for systems with complex dynamics, with application to control and monitoring of offshore floating wind turbines, mobile robotics, sustainable tillage, mechatronic systems, biomedical processes, active and semi-active control techniques for vibration mitigation in civil engineering structures and automotive suspension systems.Yolanda Vidal was born in Baleares, Spain, in 1977. She received the B.E. degree in mathematics in 1999 and the Ph.D. degree in Applied Mathematics in 2005 from the Universitat Politècnica de Catalunya (UPC), Barcelona, Spain. Since 2002 she has been with the Department of Applied Mathematics III of the UPC where she became an associate professor in 2009. Her current research activities are focused on modeling and control design, fault detection and isolation systems with application to control and monitoring of wind turbines.Leonardo Acho was born in the State of Mexico, Mexico, in 1967. He received the B.E. degree in electronics engineering from the Technology Institute of Monterrey (ITESM), Monterrey, Mexico, in 1989; and the M.Sc. and Ph.D. degrees in electronics and automatic control, from the Technology Institute of Monterrey (ITESM), Monterrey, Mexico, and from the Research Center of Ensenada (CICESE), México, in 1992 and 2002, respectively. Since February 2008, he has been with the Department of Applied Mathematics III of the Polytechnic University of Catalonia (UPC), Spain, where he was a Visiting Professor, and became an associate professor in 2009. His current research interests include control theory, nonlinear systems, and chaos engineering.    

Preface 6
Contents 9
Part IPower Converter Systems 11
1 Modeling and Control of PMSG-Based Variable-Speed Wind Turbine 12
Abstract 12
1.1…Introduction 13
1.2…Dynamic Model of PMSG-WT-Based Power Systems 14
1.2.1 Permanent-Magnetic Synchronous-Generator 16
1.2.2 Transmission Line 17
1.2.3 Transformer 17
1.2.4 Cable 17
1.2.5 RL Load 17
1.2.6 RL-Filter on the Grid-Side Converter 18
1.2.7 Voltage Source Converter Controller 18
1.3…The Supervisory Reactive Power Control 21
1.4…Case Studies 23
1.4.1 Wind-Speed Variation 23
1.4.2 Local-Load Variation 25
1.4.3 Voltage Sag in the Infinite Bus 25
1.4.4 Fault-Ride Through Study 26
1.5…Conclusion 28
Acknowledgment 28
A.0. Appendix 29
A.0. Future Work 29
References 30
2 High-Order Sliding Mode Control of DFIG-Based Wind Turbines 31
Abstract 31
2.1…Introduction 32
2.2…The Wind Turbine Modeling 33
2.2.1 Turbine Model 33
2.2.2 Generator Model 34
2.3…Control of the DFIG-Based Wind Turbine 36
2.3.1 Problem Formulation 36
2.3.2 High-Order Sliding Modes Control Design 37
2.3.3 High-Gain Observer 40
2.3.4 High-Order Sliding Mode Speed Observer 43
2.4…Simulation Using the FAST Code 47
2.4.1 Test Conditions 49
2.4.2 HOSM Control Performances 49
2.4.3 HOSM Control Performances with High-Gain Observer 50
2.4.4 Sensorless HOSM Control Performances 51
2.4.5 HOSM Control FRT Performances 52
2.5…Conclusions 54
2.6…Future Work 54
A.0. Appendix 54
References 55
3 Maximum Power Point Tracking Control of Wind Energy Conversion Systems 57
Abstract 57
3.1…Introduction 58
3.2…Model of Wind Turbine 59
3.3…Maximum Power Point Tracking 61
3.4…Model of Wind Energy Conversion System 62
3.5…Control Strategy for Wind Energy Integration into Power Network 66
3.5.1 DC-Link Voltage Controller Design 66
3.5.2 d-Axis Current Controller Design 68
3.5.3 q-Axis Current Controller Design 69
3.6…Simulations 70
3.6.1 Step Changes in the Load Current 71
3.6.2 Step Changes in the Source Voltage 74
3.7…Conclusions 74
Acknowledgments 74
References 74
Part IIControl 76
4 Gain Scheduled H/boldinfty& !infin
Abstract 77
4.1…Introduction 79
4.2…Wind Turbine Modeling 80
4.3…Objectives and Control Scheme 82
4.4…H/boldinfty& !infin
4.5…Wind Turbine Control Design 89
4.5.1 H/boldinfty& !infin
4.5.2 Anti-windup Compensation 92
4.6…Results 94
4.7…Conclusion 99
4.8…Future Research 100
Acknowledgments 100
References 100
5 Design of Robust Controllers for Load Reduction in Wind Turbines 102
Abstract 102
5.1…Introduction 103
5.2…General Control Concepts for Wind Turbines 105
5.2.1 Wind Turbine Non-Linear Model 107
5.2.2 Baseline Control Strategy 108
5.3…Design of Robust Controllers 111
5.3.1 Design of Hinfin Robust Controllers 112
5.3.1.1 Multivariable Generator Torque Hinfin Control 114
5.3.1.2 Multivariable Collective Pitch Hinfin Control 115
Gain Scheduled Collective Pitch Hinfin Control 119
5.3.1.3 Multivariable Individual Pitch Hinfin Control 119
5.3.2 Closed Loop Analysis of the Designed Robust Controllers 124
5.4…Simulation Results in GH Bladed 125
5.5…Conclusions 134
5.6…Future Work 135
Acknowledgments 136
References 136
6 Further Results on Modeling, Analysis, and Control Synthesis for Offshore Wind Turbine Systems 139
Abstract 139
6.1…Introduction 140
6.2…Model Description 145
6.3…Controller Design 148
6.4…Simulation Results 149
6.5…Conclusions 157
6.6…Future Work 157
A.1. 6.7…Appendix 157
References 158
7 A Fault Tolerant Control Approach to Sustainable Offshore Wind Turbines 160
Abstract 160
7.1…Introduction 162
7.2…Structure and Approaches to FTC Systems 163
7.3…Wind Turbine Modelling 165
7.4…Wind Turbine Aerodynamic and Control 171
7.5…Investigation of the Effects of Some Faults Scenarios 175
7.6…T-S Fuzzy PMIO-Based Sensor FTC 177
7.6.1 Simulation Results 183
7.7…Conclusions 188
7.8…Future Research 190
References 190
Part IIIMonitoring and Fault Diagnosis 194
8 Monitoring Ice Accumulation and Active De-icing Control of Wind Turbine Blades 195
Abstract 195
8.1…Introduction 197
8.2…Atmospheric Icing 199
8.3…Sensing and Actuation Background: Existing Methods 199
8.3.1 Ice Sensing 199
8.3.2 Thermal Actuation 200
8.4…Blade Thermodynamics 205
8.5…Direct Optical Ice Sensing 207
8.6…Distributed Localized Heating 210
8.7…Experimental Setup 211
8.8…Computational Model Validation with Experiments 215
8.9…Optimizing the Layout of Distributed Heaters 217
8.9.1 De-icing Performance Metric 219
8.9.2 De-icing Performance Comparison for Different Heater Layouts 220
8.10…Preliminary De-icing Experimental Results 224
8.10.1 Distributed Closed-Loop Control Experiments 225
8.10.2 High Intensity Pulse Amplitude Modulation 227
8.11…Conclusion 228
8.12…Future Work 230
Acknowledgments 230
References 231
9 Structural Health Monitoring of Wind Turbine Blades 233
Abstract 233
9.1…Introduction 235
9.2…Vibration-Based Damage Detection of Rotational Wind Turbine Blades 238
9.2.1 Structural Dynamic Model of Rotating Blades 238
9.2.2 Damage Detection Methodology: Principal Component Analysis 240
9.2.3 Numerical Example 242
9.2.3.1 The Wind Turbine Blade Model and Structural Dynamic Response Simulation 242
9.2.3.2 Results of Modal Analysis 243
9.2.3.3 Results of Damage Detection Based on PCA 244
9.2.4 Experimental Example 246
9.2.4.1 Composite Blade and Experimental Setup 246
9.2.4.2 Damage Detection Results Based on Experimental Data 247
9.3…Fatigue Damage Detection Based on High Spatial Resolution DPP-BOTDA 247
9.3.1 Principles of DPP-BOTDA 247
9.3.2 Fatigue Damage Detection Test 250
9.3.2.1 Experimental Setup 250
9.3.2.2 Summary of Test Procedure 252
9.3.3 Test Results and Discussions 253
9.3.3.1 Blade Failure Scenario and Mechanism 253
9.3.3.2 Damage Detection Results of the DPP-BOTDA System 255
9.4…Damage Detection under Static Loading Using PZT Sensors 257
9.4.1 Test Description 257
9.4.2 Experimental Results and Discussion 259
9.4.2.1 Results of Optical Fiber Sensors 259
9.4.2.2 Results of PZT Transformer 260
9.4.3 Fractal Theory-Based Damage Detection Method and Results 261
9.5…Conclusions and Future Work 263
References 264
10 Sensor Fault Diagnosis in Wind Turbines 268
Abstract 268
10.1…Introduction 270
10.2…Statistical Change Detection/Isolation Algorithms 271
10.2.1 Fault Detection 272
10.2.1.1 Example 273
10.2.2 Detection/Isolation Algorithm 274
10.2.3 Practical Issues 276
10.3…Individual Signal Monitoring 277
10.3.1 Excessive Noise 277
10.3.2 Application to Incremental Encoder Fault 279
10.3.2.1 Note 280
10.4…Fault Detection and Isolation Based on Hardware Redundancy 280
10.4.1 Residual Generation 280
10.5…Fault Detection and Isolation Based on Analytical Redundancy 283
10.5.1 Model of a Balanced Three-Phase System 284
10.5.2 Residual Generation 285
10.5.3 Fault Detection and Isolation in the Stator Voltage and Current Sensors of a Wind Driven DFIG 288
10.5.3.1 Problem Statement 288
10.5.3.2 Residual Generator and Decision System Design 290
10.5.3.3 Simulation Scenario 291
10.5.3.4 Results and Discussion 293
10.6…Conclusion 297
10.7…Future Work 298
References 298
11 Structural Load Analysis of Floating Wind Turbines Under Blade Pitch System Faults 301
Abstract 301
11.1…Introduction 303
11.2…Wind Turbine 308
11.2.1 Reference Wind Turbine 308
11.2.2 Regions of Operation 308
11.2.3 Wind Turbine Control 310
11.2.3.1 Blade Pitch Control 311
11.2.3.2 Generator Torque Control 312
11.2.4 Pitch System 313
11.3…Faults 314
11.3.1 Sensor Faults 315
11.3.1.1 Bias 315
11.3.1.2 Gain 316
11.3.1.3 Complete Failure 316
11.3.2 Pitch System Faults 316
11.3.2.1 Performance Degradation 316
11.3.2.2 Actuator Stuck 316
11.3.2.3 Pitch Runaway 317
11.3.2.4 Bias Error 317
11.4…Simulation Setup 317
11.4.1 Environmental Conditions 318
11.4.2 Fault Scenarios 319
11.5…Results Discussion and Analysis 322
11.5.1 Performance Indices 322
11.5.2 Blade Pitch Bias Fault 323
11.5.3 Blade Pitch Gain Fault 325
11.5.4 Actuator Performance Degradation 325
11.5.5 Actuator Stuck 327
11.5.6 Actuator Runaway 328
11.6…Conclusion 332
References 333
Part IVVibration Mitigation 335
12 Vibration Mitigation of Wind Turbine Towers with Tuned Mass Dampers 336
Abstract 336
12.1…Introduction 337
12.2…Tower Vibrations 338
12.2.1 Wind Loading 338
12.2.2 Seismic Loading 340
12.2.3 Soil-Structure Interaction 342
12.3…Vibration Mitigation Methods 346
12.3.1 Blade Pitch Control and Brake Systems 347
12.3.2 Dampers 347
12.3.3 Tuned Mass Dampers 348
12.3.3.1 Calculation of Optimal Parameters of Tuned Mass Damper 348
12.3.4 Tuned Liquid Dampers 349
12.3.4.1 Tuned Sloshing Dampers 349
12.3.4.2 Tuned Liquid Column Dampers 350
Mathematical Description 350
Calculation of Optimal Parameters of Tuned Liquid Column Damper 352
Semiactive Tuned Liquid Column Dampers 352
12.4…Reference Wind Turbine with Tuned Mass Damper 353
12.4.1 System Properties of the Reference Wind Turbine 354
12.4.2 General Simulation Parameters 354
12.4.3 Simulation Results 355
12.4.3.1 Onshore Reference Wind Turbine with a Tuned Mass Damper 355
12.4.3.2 Onshore Reference Wind Turbine with a Tuned Liquid Column Damper 358
12.4.3.3 Seismically Excited Onshore Reference Wind Turbine with Tuned Mass Damper 361
12.4.3.4 Onshore Reference Wind Turbine with Tuned Mass Damper Considering Soil-Structure Interaction 365
12.5…Conclusion 369
12.6…Future Work 370
Acknowledgments 370
References 370
13 A Semi-active Control System for Wind Turbines 373
Abstract 373
13.1…Introduction 374
13.2…Basic Idea of the Semi-active Control Strategy 375
13.3…Experimental Setup 376
13.3.1 Electronic Equipment and Transducers 378
13.4…Magnetorheological Dampers 381
13.5…Control Algorithms 385
13.5.1 Closed-Loop Eigenstructure Selection (CLES) Algorithm 390
13.5.2 Two Variables (2VAR) Algorithm 394
13.6…Experimental Activity and Results 395
13.6.1 SA Control for the Extreme Operating Gust Load Case 398
13.6.1.1 CLES Controller: Response Reduction Under the EOG Load Case 398
13.6.1.2 2VAR Controller: Response Reduction Under the EOG Load Case 398
13.6.2 SA Control for the Parking Load Case 400
13.6.2.1 CLES Controller: Response Reduction Under the PRK Load Case 401
13.6.2.2 2VAR Controller: Response Reduction Under the PRK Load Case 402
13.7…Conclusions 403
References 404
Part VTest-Bench for Research/Education 406
14 Wind Farm Lab Test-Bench for Research/Education on Optimum Design and Cooperative Control of Wind Turbines 407
Abstract 407
14.1…Introduction 408
14.2…System Description 408
14.2.1 Wind Turbine Description 408
14.2.1.1 Aerodynamics: Rotor Blades 410
14.2.1.2 Mechanics: Main Structures, Power Train, Tower, Nacelle, Gearboxes 411
14.2.1.3 Electrical Components: Generator, Grid Connection 412
14.2.1.4 Sensors: Rotor Speed, Pitch and Yaw Angles, Voltage, Currents, Torque, Power, Wind 413
14.2.1.5 Actuators: Pitch and Yaw Motors, Torque 415
14.2.1.6 WT Microprocessors: Real-Time Control for Rotor Speed, Pitch, Yaw, Torque, Power 415
14.2.2 Wind Farm Description 416
14.2.3 Supervisory Control and Data Acquisition (SCADA) System 416
14.2.4 Smart Micro Grid 417
14.2.5 Wind Source Equipment 417
14.3…Modeling of Wind Turbines 418
14.3.1 Power Curve of a Wind Turbine 418
14.3.2 Power Generation According to the Number of Blades 419
14.3.3 Dynamics of Rotor Speed Versus Torque, Pitch Angle and Wind Velocity Variation 420
14.4…System Identification 425
14.4.1 Rotor-Speed Versus Pitch-Angle Transfer Function F2(S) 425
14.4.2 Rotor-Speed Versus Electrical-Torque Transfer Function F3(S) 427
14.4.3 Rotor Speed Versus Wind Speed Transfer Function F1(S) 429
14.5…Control System Design 429
14.5.1 Rotor Speed Control System 429
14.5.1.1 Control Objectives and Configuration 429
14.5.1.2 Modeling 430
14.5.1.3 Control Specifications 430
14.5.1.4 Controller Design 432
14.5.2 Power/Torque Control System 432
14.6…Research and Education Experiments 434
14.6.1 Effect of Number of Blades, Aerodynamic and Generator Efficiency 434
14.6.2 Rotor Speed Control with Pitch System 436
14.6.3 Maximum Power Point Tracking for Individual Wind Turbine 436
14.6.4 Estimation of the Cp/ lambda Characteristic of the 6-Blade Rotor Wind Turbine 439
14.6.5 Power Curve for the 6-Blade Rotor Wind Turbine 439
14.6.6 Wind Farm Topology Configurations and Effect on Power Efficiency 440
14.7…Conclusions 443
14.8…Future Work 443
Acknowledgments 443
References 443
15 Hardware in the Loop Wind Turbine Simulator for Control System Testing 445
Abstract 445
15.1…Introduction 446
15.2…HIL Test Setup 447
15.2.1 FAST (Wind Turbine Simulator) 448
15.2.2 Arduino Microcontroller Board 449
15.2.3 Setup 450
15.3…Onshore Reference Wind Turbine 451
15.4…Wind Modeling 451
15.5…Control Strategy 452
15.5.1 Baseline Torque Controller 452
15.5.2 Chattering Torque Control 453
15.5.3 Pitch Control 454
15.6…HIL Results 455
15.6.1 Healthy 455
15.6.2 Faulty 455
15.7…Conclusions 458
Appendix 458
Acknowledgments 461
References 461