Dynamic Vulnerability Assessment and Intelligent Control

Edited by José Luis Rueda-Torres received the Electrical Engineer Diploma from Escuela Politécnica Nacional, Quito, Ecuador, cum laude honors, in August 2004. In November 2009, he received a Ph.D. in electrical engineering from the National University of San Juan, obtaining the highest mark 'Sobresaliente' (Outstanding). He is currently working as an Assistant Professor for Intelligent Electrical Power Grids at the Department of Electrical Sustainable Energy, Technical University Delft, Netherlands. He is vice-chair of the Working Group on Modern Heuristic Optimization (WGMHO) under the IEEE PES Power System Analysis, Computing, and Economics Committee. Dr. Rueda-Torres is a member of CIGRE and a senior member of the IEEE. His current research interests include power system planning, power system stability and control, and probabilistic and artificial intelligence methods. Francisco González-Longatt received an Electrical Engineering degree from Instituto Universitario Politécnico de la Fuerza Armada Nacional (1994), Master of Business Administration from Universidad Bicentenaria de Aragua (1999), a Ph.D. in Electrical Power Engineering from the Universidad Central de Venezuela (2008), and a Postgraduate Certificate in Higher Education Professional Practice from Coventry University (2013). He is a Lecturer in Electrical Power Systems in the School of Electronic, Electrical and Systems Engineering at Loughborough University, UK, and the Vice-President of the Venezuelan Wind Energy Association. Dr González-Longatt is a member of CIGRE and a senior member of the IEEE. His current research interests include innovative (operation/control) schemes to optimize the performance of future energy systems.

List of Contributors xv

Foreword xix

Preface xxi

1 Introduction: The Role of Wide Area Monitoring Systems in Dynamic Vulnerability Assessment 1

Jaime C. Cepeda and José Luis Rueda-Torres

1.1 Introduction 1

1.2 Power System Vulnerability 2

1.2.1 Vulnerability Assessment 2

1.2.2 Timescale of Power System Actions and Operations 4

1.3 Power System Vulnerability Symptoms 5

1.3.1 Rotor Angle Stability 6

1.3.2 Short-Term Voltage Stability 7

1.3.3 Short-Term Frequency Stability 7

1.3.4 Post-Contingency Overloads 7

1.4 Synchronized Phasor Measurement Technology 8

1.4.1 Phasor Representation of Sinusoids 8

1.4.2 Synchronized Phasors 9

1.4.3 Phasor Measurement Units (PMUs) 9

1.4.4 Discrete Fourier Transform and Phasor Calculation 10

1.4.5 Wide Area Monitoring Systems 10

1.4.6 WAMPAC Communication Time Delay 12

1.5 The Fundamental Role of WAMS in Dynamic Vulnerability Assessment 13

1.6 Concluding Remarks 16

2 Steady-state Security 21

Evelyn Heylen, Steven De Boeck, Marten Ovaere, Hakan Ergun, and Dirk Van Hertem

2.1 Power System Reliability Management: A Combination of Reliability Assessment and Reliability Control 22

2.1.1 Reliability Assessment 23

2.1.2 Reliability Control 24

2.2 Reliability Under Various Timeframes 31

2.3 Reliability Criteria 33

2.4 Reliability and Its Cost as a Function of Uncertainty 34

2.4.1 Reliability Costs 34

2.4.2 Interruption Costs 35

2.4.3 Minimizing the Sum of Reliability and Interruption Costs 36

3 Probabilistic Indicators for the Assessment of Reliability and Security of Future Power Systems 41

Bart W. Tuinema, Nikoleta Kandalepa, and José Luis Rueda-Torres

3.1 Introduction 41

3.2 Time Horizons in the Planning and Operation of Power Systems 42

3.2.1 Time Horizons 42

3.2.2 Overlapping and Interaction 42

3.2.3 Remedial Actions 42

3.3 Reliability Indicators 45

3.3.1 Security-of-Supply Related Indicators 45

3.3.2 Additional Indicators 47

3.4 Reliability Analysis 49

3.4.1 Input Information 49

3.4.2 Pre-calculations 50

3.4.3 Reliability Analysis 50

3.4.4 Output: Reliability Indicators 53

3.5 Application Example: EHV Underground Cables 53

3.5.1 Input Parameters 54

3.5.2 Results of Analysis 56

4 An Enhanced WAMS-based Power System Oscillation Analysis Approach 63

Qing Liu, Hassan Bevrani, and Yasunori Mitani

4.1 Introduction 63

4.2 HHT Method 65

4.2.1 EMD 65

4.2.2 Hilbert Transform 65

4.2.3 Hilbert Spectrum and Hilbert Marginal Spectrum 66

4.2.4 HHT Issues 67

4.3 The Enhanced HHT Method 71

4.3.1 Data Pre-treatment Processing 71

4.3.2 Inhibiting the Boundary End Effect 75

4.3.3 Parameter Identification 80

4.4 Enhanced HHT Method Evaluation 81

4.4.1 Case I 81

4.4.2 Case II 84

4.4.3 Case III 85

4.5 Application to RealWide Area Measurements 88

5 Pattern Recognition-Based Approach for Dynamic Vulnerability Status Prediction 95

Jaime C. Cepeda, José Luis Rueda-Torres, Delia G. Colomé, and István Erlich

5.1 Introduction 95

5.2 Post-contingency Dynamic Vulnerability Regions 96

5.3 Recognition of Post-contingency DVRs 97

5.3.1 N-1 Contingency Monte Carlo Simulation 98

5.3.2 Post-contingency Pattern Recognition Method 100

5.3.3 Definition of Data-TimeWindows 103

5.3.4 Identification of Post-contingency DVRs—Case Study 104

5.4 Real-Time Vulnerability Status Prediction 109

5.4.1 Support Vector Classifier (SVC) Training 112

5.4.2 SVC Real-Time Implementation 113

5.5 Concluding Remarks 115

6 Performance Indicator-Based Real-Time Vulnerability Assessment 119

Jaime C. Cepeda, José Luis Rueda-Torres, Delia G. Colomé, and István Erlich

6.1 Introduction 119

6.2 Overview of the Proposed Vulnerability Assessment Methodology 120

6.3 Real-Time Area Coherency Identification 122

6.3.1 Associated PMU Coherent Areas 122

6.4 TVFS Vulnerability Performance Indicators 125

6.4.1 Transient Stability Index (TSI) 125

6.4.2 Voltage Deviation Index (VDI) 128

6.4.3 Frequency Deviation Index (FDI) 131

6.4.4 Assessment of TVFS Security Level for the Illustrative Examples 131

6.4.5 Complete TVFS Real-Time Vulnerability Assessment 133

6.5 Slower Phenomena Vulnerability Performance Indicators 137

6.5.1 Oscillatory Index (OSI) 137

6.5.2 Overload Index (OVI) 141

6.6 Concluding Remarks 145

7 Challenges Ahead Risk-Based AC Optimal Power Flow Under Uncertainty for Smart Sustainable Power Systems 149

Florin Capitanescu

7.1 Chapter Overview 149

7.2 Conventional (Deterministic) AC Optimal Power Flow (OPF) 150

7.2.1 Introduction 150

7.2.2 Abstract Mathematical Formulation of the OPF Problem 150

7.2.3 OPF Solution via Interior-Point Method 151

7.2.4 Illustrative Example 154

7.3 Risk-Based OPF 158

7.3.1 Motivation and Principle 158

7.3.2 Risk-Based OPF Problem Formulation 159

7.3.3 Illustrative Example 160

7.4 OPF Under Uncertainty 162

7.4.1 Motivation and Potential Approaches 162

7.4.2 Robust Optimization Framework 162

7.4.3 Methodology for Solving the R-OPF Problem 163

7.4.4 Illustrative Example 164

7.5 Advanced Issues and Outlook 169

7.5.1 Conventional OPF 169

7.5.2 Beyond the Scope of Conventional OPF: Risk, Uncertainty, Smarter Sustainable Grid 172

8 Modeling Preventive and Corrective Actions Using Linear Formulation 177

Tom Van Acker and Dirk Van Hertem

8.1 Introduction 177

8.2 Security Constrained OPF 178

8.3 Available Control Actions in AC Power Systems 178

8.3.1 Generator Redispatch 179

8.3.2 Load Shedding and Demand Side Management 179

8.3.3 Phase Shifting Transformer 179

8.3.4 Switching Actions 180

8.3.5 Reactive Power Management 180

8.3.6 Special Protection Schemes 180

8.4 Linear Implementation of Control Actions in a SCOPF Environment 180

8.4.1 Generator Redispatch 181

8.4.2 Load Shedding and Demand Side Management 182

8.4.3 Phase Shifting Transformer 183

8.4.4 Switching 184

8.5 Case Study of Preventive and Corrective Actions 185

8.5.1 Case Study 1: Generator Redispatch and Load Shedding (CS1) 186

8.5.2 Case Study 2: Generator Redispatch, Load Shedding and PST (CS2) 187

8.5.3 Case Study 3: Generator Redispatch, Load Shedding and Switching (CS3) 190

9 Model-based Predictive Control for Damping Electromechanical Oscillations in Power Systems 193

DaWang

9.1 Introduction 193

9.2 MPC BasicTheory & Damping Controller Models 194

9.2.1 What is MPC? 194

9.2.2 Damping Controller Models 196

9.3 MPC for Damping Oscillations 198

9.3.1 Outline of Idea 198

9.3.2 Mathematical Formulation 199

9.3.3 Proposed Control Schemes 200

9.4 Test System & Simulation Setting 204

9.5 Performance Analysis of MPC Schemes 204

9.5.1 Centralized MPC 204

9.5.2 Distributed MPC 209

9.5.3 Hierarchical MPC 209

9.6 Conclusions and Discussions 213

10 Voltage Stability Enhancement by Computational Intelligence Methods 217

Worawat Nakawiro

10.1 Introduction 217

10.2 Theoretical Background 218

10.2.1 Voltage Stability Assessment 218

10.2.2 Sensitivity Analysis 219

10.2.3 Optimal Power Flow 220

10.2.4 Artificial Neural Network 220

10.2.5 Ant Colony Optimisation 221

10.3 Test Power System 223

10.4 Example 1: Preventive Measure 224

10.4.1 Problem Statement 224

10.4.2 Simulation Results 225

10.5 Example 2: Corrective Measure 226

10.5.1 Problem Statement 226

10.5.2 Simulation Results 227

11 Knowledge-Based Primary and Optimization-Based Secondary Control of Multi-terminal HVDCGrids 233

Adedotun J. Agbemuko, Mario Ndreko, Marjan Popov, José Luis Rueda-Torres, and Mart A.M.M van der Meijden

11.1 Introduction 234

11.2 Conventional Control Schemes in HV-MTDC Grids 234

11.3 Principles of Fuzzy-Based Control 236

11.4 Implementation of the Knowledge-Based Power-Voltage Droop Control Strategy 236

11.4.1 Control Scheme for Primary and Secondary Power-Voltage Control 237

11.4.2 Input/Output Variables 238

11.4.3 Knowledge Base and Inference Engine 241

11.4.4 Defuzzification and Output 241

11.5 Optimization-Based Secondary Control Strategy 242

11.5.1 Fitness Function 242

11.5.2 Constraints 244

11.6 Simulation Results 245

11.6.1 Set Point Change 245

11.6.2 Constantly Changing Reference Set Points 246

11.6.3 Sudden Disconnection ofWind Farm for Undefined Period 246

11.6.4 Permanent Outage of VSC 3 247

12 Model Based Voltage/Reactive Control in Sustainable Distribution Systems 251

Hoan Van Pham and Sultan Nasiruddin Ahmed

12.1 Introduction 251

12.2 BackgroundTheory 252

12.2.1 Voltage Control 252

12.2.2 Model Predictive Control 253

12.2.3 Model Analysis 255

12.2.4 Implementation 257

12.3 MPC Based Voltage/Reactive Controller – an Example 258

12.3.1 Control Scheme 258

12.3.2 Overall Objective Function of the MPC Based Controller 259

12.3.3 Implementation of the MPC Based Controller 261

12.4 Test Results 262

12.4.1 Test System and Measurement Deployment 262

12.4.2 Parameter Setup and Algorithm Selection for the Controller 263

12.4.3 Results and Discussion 263

12.5 Conclusions 266

13 Multi-Agent based Approach for Intelligent Control of Reactive Power Injection in Transmission Systems 269

Hoan Van Pham and Sultan Nasiruddin Ahmed

13.1 Introduction 269

13.2 System Model and Problem Formulation 270

13.3 Multi-Agent Based Approach 275

13.3.1 Augmented Lagrange Formulation 275

13.3.2 Implementation Algorithm 275

13.4 Case Studies and Simulation Results 277

13.4.1 Case Studies 277

13.4.2 Simulation Results 277

14 Operation of Distribution SystemsWithin Secure Limits Using Real-Time Model Predictive Control 283

Hamid Soleimani Bidgoli, Gustavo Valverde, Petros Aristidou, Mevludin Glavic, and Thierry Van Cutsem

14.1 Introduction 283

14.2 Basic MPC Principles 285

14.3 Control Problem Formulation 285

14.4 Voltage CorrectionWith Minimum Control Effort 288

14.4.1 Inclusion of LTC Actions as Known Disturbances 289

14.4.2 Problem Formulation 290

14.5 Correction of Voltages and Congestion Management with Minimum Deviation from References 291

14.5.4 Problem Formulation 295

14.6 Test System 296

14.7 Simulation Results: Voltage Correction with Minimal Control Effort 298

14.8 Simulation Results: Voltage and/or Congestion Corrections with Minimum Deviation from Reference 302

15 Enhancement of Transmission System Voltage Stability through Local Control of Distribution Networks 311

Gustavo Valverde, Petros Aristidou, and Thierry Van Cutsem

15.1 Introduction 311

15.2 Long-Term Voltage Stability 313

15.2.1 Countermeasures 314

15.3 Impact of Volt-VAR Control on Long-Term Voltage Stability 316

15.3.1 Countermeasures 318

15.4 Test System Description 319

15.4.1 Test System 319

15.4.2 VVC Algorithm 321

15.4.3 Emergency Detection 322

15.5 Case Studies and Simulation Results 323

15.5.1 Results in Stable Scenarios 323

15.5.2 Results in Unstable Scenarios 326

15.5.3 Results with Emergency Support From Distribution 328

16 Electric Power Network Splitting Considering Frequency Dynamics and Transmission Overloading Constraints 337

Nelson Granda and Delia G. Colomé

16.1 Introduction 337

16.1.1 Stage One: Vulnerability Assessment 337

16.1.2 Stage Two: Islanding Process 338

16.2 Network Splitting Mechanism 340

16.2.1 Graph Modeling, Update, and Reduction 341

16.2.2 Graph Partitioning Procedure 342

16.2.3 Load Shedding/Generation Tripping Schemes 343

16.2.4 Tie-Lines Determination 344

16.3 Power Imbalance Constraint Limits 344

16.3.1 Reduced Frequency ResponseModel 345

16.3.2 Power Imbalance Constraint Limits Determination 347

16.4 Overload Assessment and Control 348

16.5 Test Results 349

16.5.1 Power System Collapse 349

16.5.2 Application of Proposed Methodology 351

16.5.3 Performance of Proposed ACIS 354

16.6 Conclusions and Recommendations 356

17 High-Speed Transmission Line Protection Based on Empirical Orthogonal Functions 361

Rommel P. Aguilar and Fabián E. Pérez-Yauli

17.1 Introduction 361

17.2 Empirical Orthogonal Functions 363

17.2.1 Formulation 363

17.3 Applications of EOFs for Transmission Line Protection 365

17.3.1 Fault Direction 366

17.3.2 Fault Classification 367

17.3.3 Fault Location 369

17.4 Study Case 369

17.4.1 Transmission Line Model and Simulation 369

17.4.2 The Power System and Transmission Line 370

17.4.3 Training Data 370

17.4.4 Training Data Matrix 370

17.4.5 Signal Conditioning 373

17.4.6 Energy Patterns 373

17.4.7 EOF Analysis 376

17.4.8 Evaluation of the Protection Scheme 379

17.4.9 Fault Classification 380

17.4.10 Fault Location 382

17.5 Conclusions 383

Study Cases:WECC 9-bus, ATPDrawModels and Parameters 384

18 Implementation of a Real Phasor Based Vulnerability Assessment and Control Scheme: The Ecuadorian WAMPAC System 389

Pablo X. Verdugo, Jaime C. Cepeda, Aharon B. De La Torre, and Diego E. Echeverría

18.1 Introduction 389

18.2 PMU Location in the Ecuadorian SNI 390

18.3 Steady-State Angle Stability 391

18.4 Steady-State Voltage Stability 395

18.5 Oscillatory Stability 398

18.5.1 Power System Stabilizer Tuning 402

18.6 Ecuadorian Special Protection Scheme (SPS) 407

18.6.1 SPS Operation Analysis 409

18.7 Concluding Remarks 410

Index 413