Smart Hybrid AC/DC Microgrids – Power Management, Energy Management, and Power Quality Control: IEEE Press

Author Biographies xiii Preface xv Part I Smart Hybrid AC/DC Microgrids 1 1 Smart Hybrid AC/DC Microgrids 3 1.1 Introduction to Microgrids 3 1.1.1 Concept of Microgrids 3 1.1.2 Development of Microgrids 4 1.1.3 Features of Modern Microgrids 6 1.2 Smart Hybrid Microgrid Configurations 8 1.2.1 AC-coupled Hybrid Microgrid 8 1.2.2 DC-coupled Hybrid Microgrid 9 1.2.3 AC/DC-Coupled Hybrid Microgrid 10 1.2.4 Examples of Hybrid Microgrids 11 1.3 Smart Hybrid Microgrid Operations 14 1.3.1 Distributed Generation and Energy Storage Systems 14 1.3.2 Smart Interfacing Converters 16 1.3.3 Cyber Systems 16 1.3.4 Power Management and Energy Management Systems 17 1.3.5 Power Quality 17 1.4 Outline of the Book 18 References 20 2 Renewable Energy, Energy Storage, and Smart Interfacing Power Converters 21 2.1 Renewable-based Generation 21 2.1.1 Photovoltaic (PV) Power Systems 21 2.1.2 Wind Power Systems 29 2.2 Energy Storage Systems 37 2.2.1 Battery Energy Storage System 38 2.2.2 Flywheel Energy Storage System 43 2.2.3 Superconducting Magnet Energy Storage System 44 2.2.4 Hydrogen and Fuel Cell Energy Storage 45 2.3 Integration of Renewable Energy and Energy Storage 49 2.3.1 Structure of Smart Interfacing Converters (IFCs) 49 2.3.2 Operation and Coordination 52 2.4 Summary 54 References 54 3 Smart Microgrid Communications 55 3.1 Introduction 55 3.2 Communication Technique for Smart Microgrids 57 3.2.1 Basic Concepts of Communication Systems 57 3.2.2 Structures of Communication Networks in Smart Microgrids 59 3.2.3 Requirements of Communication in Smart Microgrids 61 3.2.4 Wired Communication Technologies in a Microgrid 62 3.2.5 Wireless Communication Technologies 65 3.3 Standards and Protocols in Smart Microgrids 67 3.3.1 Standards and Protocols for General Communication 67 3.3.2 Standards and Protocols for Substation Automation 70 3.3.3 Standards and Protocols for Control Center and Wide Area Monitoring 71 3.3.4 Standards and Protocols for Distributed Generation and Demand Response 72 3.3.5 Standards and Protocols for Metering 73 3.3.6 Standards and Protocols for Electric Vehicle Charging 74 3.4 Network Cyber-security 75 3.5 Summary 78 References 78 Part II Power Management Systems (PMSs) and Energy Management Systems (EMSs) 81 4 Smart Interfacing Power Electronics Converter Control 83 4.1 Primary Control of Power Electronics Converters 83 4.1.1 Basic Control Techniques in Power Converters 84 4.1.2 Current Control Method 90 4.1.3 Voltage Control Method 92 4.2 Virtual Impedance Control of Power Electronic Converters 93 4.2.1 Internal Virtual Impedance 94 4.2.2 External Virtual Impedance 96 4.2.3 Integration of both Internal and External Virtual Impedance 97 4.3 Droop Control of Power Electronics Converters 99 4.3.1 Frequency and Voltage Droop Control in an AC Subgrid 99 4.3.2 Voltage Droop Control in DC Subgrids 102 4.3.3 Unified Droop for Interlinking AC and DC Subgrids 102 4.3.4 Challenges of Droop Control and Solutions 105 4.4 Virtual Synchronous Generator (VSG) Control of Interfacing Power Electronics Converters 110 4.4.1 Principles of VSG Control 111 4.4.2 Implementation of VSG Control 112 4.4.3 Relationship Between Droop Control and VSG Control 115 4.5 Unified Control of Power Electronics Converters 116 4.6 Summary 118 References 118 5 Power Management System (PMS) in Smart Hybrid AC/DC Microgrids 121 5.1 Introduction 121 5.2 Hierarchical Control of Hybrid Microgrids 122 5.3 Power Management Systems (PMSs) in Different Structures of Hybrid Microgrids 125 5.3.1 PMS of an AC-coupled Hybrid Microgrid 125 5.3.2 PMS of a DC-coupled Hybrid Microgrid 128 5.3.3 PMS of an AC-DC-coupled Hybrid Microgrid 130 5.4 Power Management Strategies During Transitions and Different Loading Conditions 133 5.4.1 PMS During Transition Between Grid-Connected and Islanding Operation Modes 133 5.4.2 Power Management Strategies Under Different Loading Conditions 137 5.5 Implemented Examples of Power Management Systems in Hybrid Microgrids 137 5.5.1 PMS Example of an AC-coupled Hybrid Microgrid 137 5.5.2 PMS Example of a DC-coupled Hybrid Microgrid 140 5.5.3 PMS Example of an AC-DC-coupled Hybrid Microgrid 143 5.6 Black Start in Hybrid Microgrids 146 5.6.1 General Requirements of Black Start in Microgrids 147 5.6.2 Microgrid Black Start Scheme 147 5.6.3 Main Issues and Related Measures of Black Starts in Microgrids 152 5.7 Summary 153 References 153 6 Energy Management System (EMS) in Smart Hybrid Microgrids 155 6.1 Energy Management in Hierarchical Control of Microgrids 155 6.1.1 Hierarchical Control 155 6.1.2 Energy Management System 157 6.1.3 Communications in an Energy Management System 162 6.2 Multi-agent Control Strategy of Microgrids 162 6.3 Advance Distribution Management Systems (ADMSs) in Smart Hybrid Microgrids 165 6.3.1 Supervisory Control and Data Acquisition (SCADA) 165 6.3.2 Geographic Information Systems (GISs) 167 6.3.3 Distribution Management System (DMS) 167 6.3.4 Automated Meter Reading/Automatic Metering Infrastructure (amr/ami) 168 6.3.5 Outage Management Systems (OMSs) 168 6.3.6 Distributed Energy Resource Management System (DERMS) 169 6.4 Cyber-security in Smart Hybrid Microgrids 170 6.4.1 Different Types of Cyber-security Violations 170 6.4.2 Impacts of Cyber-security Violations on Smart Microgrids 172 6.4.3 Construction of Cyber-security Violations in Smart Microgrids 173 6.4.4 Defensive Strategies Against Cyber-attacks 174 6.4.5 Case Study Example: Cyber-security Violations in Power Electronics-intensive DC Microgrids 176 6.4.6 Future Trends of Microgrid Cyber-security 181 6.5 Summary 182 References 182 Part III Power Quality Issues and Control in Smart Hybrid Microgrids 185 7 Overview of Power Quality in Microgrids 187 7.1 Introduction 187 7.2 Classification of Power Quality Disturbances 188 7.2.1 Transients 188 7.2.2 Short Duration Variations 189 7.2.3 Long Duration Variations 191 7.2.4 Voltage Fluctuations 191 7.2.5 Voltage Imbalance 191 7.2.6 Power Frequency Variations 192 7.2.7 Waveform Distortion 192 7.3 Overview of Power Quality Standards 193 7.4 Mitigation Techniques of Power Quality Problems 198 7.4.1 Passive Mitigation Solutions 198 7.4.2 Active Mitigation Solutions 202 7.5 Power Quality Issues and Compensation in Microgrids 210 7.5.1 Power Quality Issues in an AC Microgrid 210 7.5.2 Power Quality in a Hybrid AC/DC Microgrid 213 7.6 Summary 216 References 216 8 Smart Microgrid Control During Grid Disturbances 219 8.1 Introduction 219 8.2 Islanding Detection 220 8.2.1 Local Islanding Detection Methods 221 8.2.2 Remote Islanding Detection Methods 225 8.2.3 Signal Processing Techniques Used in Islanding Detection 226 8.2.4 Intelligent Techniques Used in Islanding Detection 227 8.3 Fault Ride-through Capability 228 8.3.1 Fault Ride-through Requirement 229 8.3.2 Ride-through Enhancement 232 8.4 Fault Current Contribution and Protection Coordination 240 8.4.1 Impact of DG on Fuse-recloser Coordination 241 8.4.2 Impact of Reactive Power Injection on Fuse-recloser Coordination 244 8.4.3 Example of Inverter Current Control Strategy under RT 245 8.5 Summary 250 References 250 9 Unbalanced Voltage Compensation in Smart Hybrid Microgrids 253 9.1 Introduction 253 9.2 Control of Individual Three-phase IFCs for Unbalanced Voltage Compensation 254 9.2.1 Three-phase IFC Model under Unbalanced Voltage 255 9.2.2 Control of Unbalanced Voltage Adverse Effects on IFC Operation 259 9.2.3 Adjustable Unbalanced Voltage Compensation with IFC Active Power Oscillation Minimization 260 9.3 Control of Parallel Three-phase IFCs for Unbalance Voltage Compensation 262 9.3.1 Parallel Three-phase IFCs Model under Unbalanced Voltage 263 9.3.2 Parallel Three-phase IFCs Control under Unbalanced Voltage: Redundant IFC for DeltaP Cancelation 267 9.3.3 Parallel Three-phase IFCs Control under Unbalanced Voltage: All Parallel IFCs Participate in DeltaP Cancelation 271 9.4 Control of Single-phase IFCs for Three-phase System Unbalanced Voltage Compensation 276 9.4.1 System Model with Embedded Single-phase IFCs under Three-phase Unbalanced Voltage 276 9.4.2 Reactive Power Control of Single-phase IFCs for Three-phase AC Subgrid Unbalanced Voltage Compensation 280 9.5 Summary 288 References 289 10 Harmonic Compensation Control in Smart Hybrid Microgrids 291 10.1 Introduction 291 10.2 Control of Interfacing Power Converters for Harmonic Compensation in AC Subgrids 292 10.2.1 Harmonics Compensation with the Current Control Method (CCM) 296 10.2.2 Harmonics Compensation with the Voltage Control Method (VCM) 298 10.2.3 Harmonics Compensation with the Hybrid Control Method (HCM) 301 10.2.4 Comparison of Harmonics Compensation with the CCM, the VCM, and the HCM 305 10.3 Control of Low-switching Interfacing Power Converters for Harmonics Compensation in an AC Subgrid 308 10.3.1 Low-switching Interfacing Converters Sampling Methods 309 10.3.2 Control of Low-switching IFCs for Harmonics Compensation with Feed-forward Strategy 311 10.4 Control of Interfacing Power Converters for Harmonics Compensation in a DC Subgrid 317 10.4.1 Harmonics Compensation in a DC Subgrid Using DC/AC Interlinking Power Converters 319 10.4.2 Harmonics Compensation in a DC Subgrid Using DC/DC Interfacing Power Converters 320 10.5 Coordinated Control of Multiple Interfacing Power Converters for Harmonics Compensation 321 10.5.1 Autonomous Harmonic Control 322 10.5.2 Supervisory Harmonic Control 322 10.6 Summary 329 References 329 A Instantaneous Power Theory from Three-phase and Single-phase System Perspectives 331 A. 1 Introduction 331 A. 2 Principles of Instantaneous Power Theory 331 A. 3 Power Control Using Instantaneous Power Theory from a Three-phase System Perspective 333 A.3. 1 Reference Current Focusing on Unbalanced Condition Compensation 333 A.3. 2 Reference Current Focusing on Active and Reactive Power Oscillation Cancelation 335 A. 4 Power Control Using Instantaneous Power Theory from a Single-phase System Perspective 336 A. 5 Discussion 338 A.5. 1 Example 1: Only Positive Sequence Active Current Injection 338 A.5. 2 Example 2: Only Negative Sequence Active Current Injection 340 A. 6 Summary 340 References 341 B Peak Current of Interfacing Power Converters Under Unbalanced Voltage 343 B.1 Introduction 343 B.2 Peak Currents of Interfacing Converters 343 B.2.1 Individual Interfacing Converters 343 B.2.2 Parallel Interfacing Converters 346 B.3 Maximizing Power/Current Transfer Capability of Interfacing Converters 348 B.3.1 Individual IFCs Peak Currents in the Same Phase as the Collective Peak Current of Parallel IFCs 350 B.3.2 Individual IFCs Peak Currents In-phase with the Collective Peak Current of Parallel IFCs 357 B. 4 Summary 358 References 358 C case Study System Parameters 359 Index 367

Yunwei Li, Ph.D., is a Professor at the University of Alberta, Canada. His research interests include distributed generation, microgrids, renewable energy, smart grids, high power converters, and electric motor drives. Dr. Li is a Fellow of IEEE and is recognized as a Highly Cited Researcher by the Web of Science Group. He serves as the Editor-in-Chief for IEEE Transactions on Power Electronics (TPEL) Letters. Farzam Nejabatkhah, Ph.D., is a Senior Research and Development (R&D) Engineer at CYME International T&D, Eaton. His research interests include smart grids, hybrid AC/DC microgrids, power converters, and cyber-physical systems. Hao Tian, Ph.D., is a Postdoctoral Research Fellow at the University of Alberta, Canada. His research interests include microgrids and high-power converters.