Wind Power in Power Systems

Contributors xxxi

Abbreviations xlvii

Notation lvii

1 Introduction 1
Thomas Ackermann

2 Preface: Wind Power Myths Debunked 7
Michael Milligan, Kevin Porter, Edgar DeMeo, Paul Denholm, Hannele Holttinen, Brendan Kirby, Nicholas Miller, Andrew Mills, Mark O'Malley, Matthew Schuerger and Lennart Söder

2.1 Can Grid Operators Deal with the Variability of Wind Power? 7

2.2 Does Wind Power Require Back-up Generation? 8

2.3 Aren't More CO₂ Emissions Generated with Wind Power in Power Systems than Without, Due to Back-up Requirements? 9

2.4 Does Wind Power Require Storage? 9

2.5 Isn't the Existing Flexibility Already Fully Utilized? 12

2.6 How Often Does the Wind Stop Blowing Everywhere at the Same Time? 13

2.7 To What Extent can Wind Power Production be Predicted? 14

2.8 Is it Expensive to Integrate Wind? 15

2.9 Doesn't Wind Power Production Require New Transmission, and won't that Make Wind Expensive? 16

2.10 Does Wind Power have Capacity Credit? 16

2.11 Don't Wind Power Plants have Low Capacity Factors? 17

2.12 Is Wind Power Generation Cost-competitive with Coal or Nuclear? 17

2.13 Is there a Limit to How Much Wind Generation Capacity can be Accommodated by the Grid? 18

2.14 Summary 19

Acknowledgment 20

References 20

Part A Theoretical Background

3 Historical Development and Current Status of Wind Power 23
Thomas Ackermann

3.1 Introduction 23

3.2 Historical Background 24

3.3 Current Status of Wind Power Worldwide 27

3.4 Status of Wind Turbine Technology 41

3.5 Conclusions 44

Acknowledgments 44

References 44

4 Wind Power in Power Systems: An Introduction 47
Lennart Söder and Thomas Ackermann

4.1 Introduction 47

4.2 Power System History 47

4.3 Current Status of Wind Power in Power Systems 48

4.4 Network Integration Issues for Wind Power 49

4.5 Basic Electrical Engineering 50

4.6 Characteristics of Wind Power Generation 53

4.7 Basic Integration Issues Related to Wind Power 61

4.8 Conclusions 68

Appendix Mechanical Equivalent to Power System Operation with Wind Power 68

A.1 Introduction 69

A.2 Active Power Balance 69

A.3 Synchronous Machines 69

A.4 Asynchronous Machines 69

A.5 Power Electronic Interfaces 70

A.6 Frequency Control 70

A.7 Wind Power 70

A.8 Reactive Power Balance 70

A.9 Asynchronous Machines 71

A.10 Capacitors 71

A.11 Synchronous Machines 71

A.12 Power Electronic Interfaces 71

References 72

5 Generators and Power Electronics for Wind Turbines 73
Anca D. Hansen

5.1 Introduction 73

5.2 State-of-the-Art Technologies 73

5.3 Generator Concepts 90

5.4 Power Electronic Concepts 96

5.5 Power Electronic Solutions in Wind Farms 100

5.6 Conclusions 102

References 102

6 Power System Impacts of Wind Power 105
Hannele Holttinen and Ritva Hirvonen

6.1 Introduction 105

6.2 Operation of the Power System 106

6.3 Wind Power Production and the Power System 110

6.4 Effects of Wind Energy on the Power System 118

6.5 Conclusions 128

References 129

7 The Value of Wind Power 131
Lennart Söder

7.1 Introduction 131

7.2 The Value of a Power Plant 131

7.3 The Value of Wind Power 132

7.4 The Market Value of Wind Power 141

7.5 Conclusions 154

References 155

Part B Technical Regulations and Grid Code Validation

8 Power Quality Standards for Wind Turbines 159
John Olav Tande

8.1 Introduction 159

8.2 Power Quality Characteristics of Wind Turbines 160

8.3 Impact on Voltage Quality 164

8.4 Discussion 171

8.5 Conclusion 172

References 172

9 Measurement of Electrical Characteristics 175
Fritz Santjer

9.1 Introduction 175

9.2 Power Quality Measurement Procedures 176

9.3 Specification 178

9.4 Conclusions 192

References 193

10 Practical Experience with Power Quality and Wind Power 195
Åke Larsson

10.1 Introduction 195

10.2 Voltage Variations 195

10.3 Flicker 197

10.4 Harmonics 203

10.5 Transients 204

10.6 Frequency 206

10.7 Conclusions 207

References 208

11 Technical Regulations for the Interconnection of Wind Power Plants to the Power System 209
Julija Matevosyan, Sigrid M. Bolik and Thomas Ackermann

11.1 Introduction 209

11.2 Overview of Technical Regulations 209

11.3 Comparison of Technical Interconnection Regulations 218

11.4 New Interconnection Requirements at Wind Plant Level 233

11.5 Interconnection Practice 237

11.6 Conclusions 238

References 238

12 Performance Validation and Certification for Grid Codes 241
Martin Schellschmidt, Stephan Adloff and Markus Fischer

12.1 Introduction 241

12.2 History of the Certification Process 242

12.3 Steps of the Unit Certification Process 244

12.4 Steps in the Plant Certification Process 250

12.5 Experience with the Certification Process in Germany 252

12.6 Performance Validation in Canada and Spain 254

12.7 Conclusions 258

References 258

Part C Wind Power Plant and Transmission Issues

13 Electrical Design of a Wind Power Plant 263
Nicholas Miller, Reigh Walling and Richard Piwko

13.1 Introduction 263

13.2 Wind Plant Collection System Design Objectives 263

13.3 Wind Plant Performance Requirements 265

13.4 Economic Evaluation Factors 266

13.5 Collection System Electrical Design 270

13.6 Plant Control and Communication 281

References 292

14 Transmission Systems for Offshore Wind Power Plants and Operation Planning Strategies for Offshore Power Systems 293
Thomas Ackermann, Antje Orths and Krzysztof Rudion

14.1 Introduction 293

14.2 General Electrical Aspects 297

14.3 Transmission System to Shore 301

14.4 From a Cluster Approach to Offshore Transmission Grid: The Kriegers Flak Project 312

14.5 Offshore Grid Systems 312

14.6 New System Solutions for Offshore Wind Power Plants 320

14.7 Alternative Transmission Solutions 322

14.8 Conclusions 322

References 323

15 New Cable Systems for Offshore Wind Power Plants 329
Heinrich Brakelmann and Jan Brüggmann

15.1 Introduction 329

15.2 Technical Background 329

15.3 Power Transmission with Bipolar HVAC Cable Systems 331

15.4 Voltage Definitions and Transformer Groups 332

15.5 Submarine Cable Connections 334

15.6 Examples 337

15.7 HVAC Bipolar Land Cable Systems 340

15.8 Summary 343

References 343

16 New Control Concept for Offshore Wind Power Plants: Constant-Speed Turbines on a Grid with Variable Frequency 345
Eckehard Tröster

16.1 Introduction 345

16.2 Model 346

16.3 Power Limitation 347

16.4 The Park-Variable Concept 347

16.5 Calculating the Energy Yield 353

16.6 Results 354

16.7 Conclusion 358

References 359

Part D International Studies

17 Overview of Integration Studies - Methodologies and Results 363
Hannele Holttinen

17.1 Introduction 363

17.2 Wind Integration Study Set-up and Penetration Level of Wind Power 364

17.3 Methodologies for Wind Integration Studies 366

17.4 Results from Integration Studies 373

17.5 Recommendations 382

17.6 Conclusions and Future Work 383

References 384

18 Two Reference Studies on European Transmission for Wind Integration: TradeWind and EWIS 387
Frans Van Hulle

18.1 Introduction 387

18.2 TradeWind 390

18.3 The European Wind Integration Study EWIS 399

18.4 Future Transmission Needs in Europe from the Studies 408

18.5 Concluding Remarks 410

Acknowledgments 411

References 411

19 Transmission Planning for Wind Energy in the USA: Status and Prospects 413
J. Charles Smith, Dale Osborn, Richard Piwko, Robert Zavadil, Brian Parsons, Lynn Coles, David Hawkins, Warren Lasher and Bradley Nickell

19.1 Introduction 413

19.2 Transmission Planning for Energy Resources 414

19.3 Regional Planning Efforts: Status and Prospects 417

19.4 National Transmission Policy 431

19.5 Summary and Conclusions 435

Acknowledgments 436

References 436

20 Wind Power in Areas with Limited Transmission Capacity 439
Julija Matevosyan

20.1 Introduction 439

20.2 Transmission Limits 440

20.3 Transmission Capacity: Methods of Determination 445

20.4 Measures to Increase Transmission Capacity 447

20.5 Impact of Wind Generation on Available Transmission Capacity 450

20.6 Alternatives to Grid Reinforcement for the Integration of Wind Power 452

20.7 Conclusions 462

References 462

21 Wind Power and Storage 465
Aidan Tuohy and Mark O'Malley

21.1 Introduction 465

21.2 Storage Technologies 465

21.3 Storage for Wind Integration 468

21.4 Studies on Operation of Storage in Systems with High Wind Penetration 473

21.5 Discussion 483

21.6 Conclusions 485

References 485

22 Economic Aspects of Wind Power in Power Systems 489
Poul Erik Morthorst and Thomas Ackermann

22.1 Introduction 489

22.2 Costs for Network Connection and Network Upgrading 489

22.3 System Operation Costs in a Deregulated Market 496

22.4 Example of Nord Pool 500

22.5 Conclusions 515

References 516

Part E Power System Integration Experience

23 Wind Power in the Danish Power System 519
Antje G. Orths and Peter Børre Eriksen

23.1 Introduction 519

23.2 System Overview 521

23.3 Balancing Wind Power in Daily Operation 525

23.5 Conclusions and Lessons Learned 546

References 547

24 Wind Power in the German Network: Present Status and Future Challenges of Maintaining Quality of Supply 549
Matthias Luther and Wilhelm Winter

24.1 Overview 549

24.2 Wind Power Integration in Germany 550

24.3 Wind Power Flow Patterns and Reliable System Operation 553

24.4 Network Planning and Network Security Issues 555

24.6 Requirements to Ensure System Security 562

24.7 Summary: Wind Power in the German Network 566

Acknowledgments 567

References 567

25 Wind Integration in Portugal 569
Ana Estanqueiro

25.1 Introduction 569

25.2 The Portuguese Power System 570

25.3 Planning the Power System for High Wind Penetration 573

25.4 Power System Studies for a Secure Integration of Wind Generation 581

25.5 Operational Experience of Extreme Penetration of Wind Power in Portugal 585

25.6 Synthesis 593

References 593

26 Wind Power Integration Experience in Spain 595
Juan Ma. Rodríguez García, Olivia Alonso García and Miguel de la Torre Rodríguez

26.1 Introduction 595

26.2 Wind Capacity in Spain 597

26.3 Network Arrangements for Wind Power Development 599

26.4 Technical Requirements for Massive Wind Power Integration 602

26.5 Market Arrangements for Wind Power Integration 606

26.6 Operational Arrangements for Wind Power Integration 608

26.7 Future Challenges Associated with Wind Power Integration 617

26.8 Conclusions and Lessons Learned 620

References 621

27 Maximizing Renewable Generation on the Power System of Ireland and Northern Ireland 623
Jonathan O'Sullivan

27.1 Introduction 623

27.2 The Ireland and Northern Ireland Power System 624

27.3 Deregulation and the First European Energy Package 625

27.4 The Development of Renewable Policy 2020 Targets and Beyond 629

27.5 Operational Studies 632

27.6 Impact on the Operation of the Power System 636

27.7 Programme for a Secure, Sustainable Power System 638

27.8 Conclusion 646

References 646

28 Wind Power in the Power System in Texas 649
Henry Durrwachter and Warren Lasher

28.1 Overview 649

28.2 Wind Development in Texas 653

28.3 Wind Integration Issues 656

28.4 Market Impacts 662

28.5 Lessons Learned 663

28.6 Next Steps 664

References 666

29 Wind Power in the New Zealand Power System 667
Ray Brown

29.1 Introduction 667

29.2 Overview of the New Zealand Power System 668

29.3 Overview of Wind Power Installations in New Zealand 672

29.4 Technology Progression 673

29.5 Case Study: West Wind Wind Farm 674

29.6 Case Study: White Hill Wind Farm 680

29.7 Future Challenges and the Next Steps 685

29.8 Conclusion 687

References 688

30 Large-Scale Wind Power Integration into the Chinese Power System 689
Yongning Chi, Zhen Wang, Yan Li and Weisheng Wang

30.1 Introduction 689

30.2 Grid Integration Impact of High Wind Power Penetration 692

30.3 Solutions for the Grid Integration of Large-scale Wind Power 696

30.4 Grid Compliance Testing Technology 702

30.5 Smart Grid and Wind Power in China 704

30.6 Conclusions 705

References 706

31 Isolated Systems with Wind Power 707
E. Ian Baring-Gould and Per Lundsager

31.1 Introduction 707

31.2 Isolated Power Systems 708

31.3 Detailed Overview of Wind-Diesel Power Systems 713

31.4 Systems and Experience 721

31.5 Wind Power Impact on Power Quality 724

31.6 System Modelling Requirements 728

31.7 Issues During the Application of Wind-Diesel Systems 730

31.8 Conclusions and Recommendations 734

References 735

32 Wind Farms in Weak Power Networks in India 739
Poul Sørensen

32.1 Introduction 739

32.2 Network Characteristics 741

32.3 Wind Turbine Characteristics 745

32.4 Wind Turbine Influence on Grids 745

32.5 Grid Influence on Wind Turbines 748

32.6 Conclusions 751

References 751

33 Wind Power Prediction 753
Bernhard Ernst

33.1 Introduction 753

33.2 Forecast Horizons 754

33.3 Principle of Wind Power Prediction Tools 754

33.4 Day-Ahead Prediction 756

33.5 Ensemble Forecast Models/Combination of Forecast Models 757

33.6 Nowcasting and Ramp Forecasting 760

33.7 Forecast Error Evaluation 761

33.8 Lessons Learned during Recent Years 763

33.9 Future Challenges 765

References 765

Part F Dynamic Modelling of Wind Turbines For Power System Studies

34 Introduction to the Modelling of Wind Turbines 769
Hans Knudsen and Jørgen Nygård Nielsen

34.1 Introduction 769

34.2 Basic Considerations Regarding Modelling and Simulations 769

34.3 Overview of Aerodynamic Modelling 770

34.4 Basic Modelling Block Description of Wind Turbines 777

34.5 Per Unit Systems and Data for the Mechanical System 784

34.6 Different Types of Simulations and Requirements for Accuracy 788

34.7 Conclusions 796

References 796

35 A Generic Wind Power Plant Model 799
Abraham Ellis, Yuriy Kazachkov, Juan Sanchez-Gasca, Pouyan Pourbeik, Eduard Muljadi, Michael Behnke, Jens Fortmann and Slavomir Seman

35.1 Introduction 799

35.2 Power Flow Representation and Equivalencing 800

35.3 WECC Generic Dynamic Models 802

35.4 Generic Model Validation 812

35.5 Known Issues and Areas of Improvement 817

35.6 Outlook 819

References 819

36 Reduced-Order Modelling of Wind Turbines 821
Katherine Elkington, J.G. (Han) Slootweg, Mehrdad Ghandhari and Wil L. Kling

36.1 Introduction 821

36.2 Power System Dynamics Simulation 821

36.3 Current Wind Turbine Types 822

36.4 Modelling Assumptions 823

36.5 Model of a Constant-Speed Wind Turbine 824

36.6 Model of a Wind Turbine with a Doubly Fed Induction Generator 832

36.7 Model of a Wind Turbine with a Synchronous Generator 840

36.8 Model Response 845

36.9 Conclusions 845

References 845

37 High-Order Models of Doubly Fed Induction Generators 849
Eva Centeno López and Jonas Persson

37.1 Introduction 849

37.2 Advantages of Using a Doubly Fed Induction Generator 850

37.3 The Components of a Doubly Fed Induction Generator 850

37.4 Machine Equations 851

37.5 Voltage-Source Converter 859

37.6 Sequencer 861

37.7 Simulation of the Doubly Fed Induction Generator 861

37.8 Reducing the Order of the Doubly Fed Induction Generator 862

37.9 Conclusions 863

References 864

38 Full-Scale Verification of Dynamic Wind Turbine Models 865
Vladislav Akhmatov

38.1 Introduction 865

38.2 General Validation Procedure 866

38.3 Measured Parameters and Conversion 868

38.4 Validation Types 871

38.5 Further Validation Specifications 887

38.6 Conclusions 888

References 889

39 Impacts of Wind Power on Power System Stability 891
Eknath Vittal, Andrew Keane, J.G. Slootweg and Wil Kling

39.1 Power System Stability and Security 891

39.2 Rotor Angle Stability 892

39.3 Voltage Stability 897

39.4 Frequency Stability 906

39.5 Dynamic Behaviour of Wind Power Plants 909

39.6 Conclusions 911

References 911

40 Modelling of Large Wind Power Plants 913
Vladislav Akhmatov and Björn Andresen

40.1 Introduction 913

40.2 Detailed Modelling and Short-Term Stability 915

40.3 Aggregated Modelling and Fault Ride-Through 921

40.4 Wind Power Plant Controllers 926

40.5 Conclusions 931

References 932

Part G Future Issues

41 Benefits of Active Management of Distribution Systems 937
Goran Strbac, Predrag Djapic, Thomas Bopp and Nick Jenkins

41.1 Background 937

41.2 Active Management 938

41.3 Quantifying the Benefits of Active Management 941

41.4 Conclusions 949

References 950

42 Wind Power and the Smart Grid 951
J.G. Slootweg and Thomas Ackermann

42.1 Introduction 951

42.2 (Trying to) Define Smart Grids 952

42.3 Why 'Smarten' the Grid? And Why Now (or Why Not)? 955

42.4 Goals and Concepts 957

42.5 Wind Power and Smart Grids 962

42.6 Practical Application: The Danish Cell Controller Pilot Project 966

42.7 Conclusions 971

Acknowledgments 972

References 972

43 Reactive Power Capability and Voltage Control with Wind Turbines 975
Volker Diedrichs, Alfred Beekmann and Marcel Kruse

43.1 Relevance and Design Paradigm 975

43.2 Reactive Power Capability of a Wind Turbine 979

43.3 Model-Based Design of Voltage Control Systems for Wind Power Plants 982

43.4 Performance Demonstration, Model Validation and Contingency Tests 988

43.5 Voltage Control of Medium-Voltage Network 989

Reference 997

44 Hydrogen as a Means of Transporting and Balancing Wind Power Production 999
Robert Steinberger-Wilckens

44.1 Introduction 999

44.2 A Brief Introduction to Hydrogen 1000

44.3 Technology and Efficiency 1001

44.4 Reconversion to Electricity: Fuel Cells 1004

44.5 The Potential of Hydrogen in Wind Energy Storage 1006

44.6 Hydrogen Applications for Wind Energy Storage 1008

44.7 A Blueprint for a Hydrogen Distribution System 1012

44.8 Conclusions 1016

Acknowledgments 1016

References 1017

Index 1019