About the Authors -- Preface -- Acknowledgements -- 1 Introduction -- 1.1 Wind Power Development -- 1.2 Photovoltaic Power Development -- 1.3 The Grid Converter - The Key Element in Grid Integration of WT and PV Systems -- 2 Photovoltaic Inverter Structures -- 2.1 Introduction -- 2.2 Inverter Structures Derived from H-Bridge Topology -- 2.3 Inverter Structures Derived from NPC Topology -- 2.4 Typical PV Inverter Structures -- 2.5 Three-Phase PV Inverters -- 2.6 Control Structures -- 2.7 Conclusions and Future Trends -- 3 Grid Requirements for PV -- 3.1 Introduction -- 3.2 International Regulations -- 3.3 Response to Abnormal Grid Conditions -- 3.4 Power Quality -- 3.5 Anti-islanding Requirements -- 3.6 Summary -- 4 Grid Synchronization in Single-Phase Power Converters -- 4.1 Introduction -- 4.2 Grid Synchronization Techniques for Single-Phase Systems -- 4.3 Phase Detection Based on In-Quadrature Signals -- 4.4 Some PLLs Based on In-Quadrature Signal Generation -- 4.5 Some PLLs Based on Adaptive Filtering -- 4.6 The SOGI Frequency-Locked Loop -- 4.7 Summary -- 5 Islanding Detection -- 5.1 Introduction -- 5.2 Nondetection Zone -- 5.3 Overview of Islanding Detection Methods -- 5.4 Passive Islanding Detection Methods -- 5.5 Active Islanding Detection Methods -- 5.6 Summary -- 6 Grid Converter Structures forWind Turbine Systems -- 6.1 Introduction -- 6.2 WTS Power Configurations -- 6.3 Grid Power Converter Topologies -- 6.4 WTS Control -- 6.5 Summary -- 7 Grid Requirements for WT Systems -- 7.1 Introduction -- 7.2 Grid Code Evolution -- 7.3 Frequency and Voltage Deviation under Normal Operation -- 7.4 Active Power Control in Normal Operation -- 7.5 Reactive Power Control in Normal Operation -- 7.6 Behaviour under Grid Disturbances -- 7.7 Discussion of Harmonization of Grid Codes -- 7.8 Future Trends -- 7.9 Summary -- 8 Grid Synchronization in Three-Phase Power Converters -- 8.1 Introduction -- 8.2 The Three-Phase Voltage Vector under Grid Faults -- 8.3 The Synchronous Reference Frame PLL under Unbalanced and Distorted Grid Conditions.

8.4 The Decoupled Double Synchronous Reference Frame PLL (DDSRF-PLL) -- 8.5 The Double Second-Order Generalized Integrator FLL (DSOGI-FLL) -- 8.6 Summary -- 9 Grid Converter Control for WTS -- 9.1 Introduction -- 9.2 Model of the Converter -- 9.3 AC Voltage and DC Voltage Control -- 9.4 Voltage Oriented Control and Direct Power Control -- 9.5 Stand-alone, Micro-grid, Droop Control and Grid Supporting -- 9.6 Summary -- 10 Control of Grid Converters under Grid Faults -- 10.1 Introduction -- 10.2 Overview of Control Techniques for Grid-Connected Converters under Unbalanced Grid Voltage Conditions -- 10.3 Control Structures for Unbalanced Current Injection -- 10.4 Power Control under Unbalanced Grid Conditions -- 10.5 Flexible Power Control with Current Limitation -- 10.6 Summary -- 11 Grid Filter Design -- 11.1 Introduction -- 11.2 Filter Topologies -- 11.3 Design Considerations -- 11.4 Practical Examples of LCL Filters and Grid Interactions -- 11.5 Resonance Problem and Damping Solutions -- 11.6 Nonlinear Behaviour of the Filter -- 11.7 Summary -- 12 Grid Current Control -- 12.1 Introduction -- 12.2 Current Harmonic Requirements -- 12.3 Linear Current Control with Separated Modulation -- 12.4 Modulation Techniques -- 12.5 Operating Limits of the Current-Controlled Converter -- 12.6 Practical Example -- 12.7 Summary -- Appendix A Space Vector Transformations of Three-Phase Systems -- A.1 Introduction -- A.2 Symmetrical Components in the Frequency Domain -- A.3 Symmetrical Components in the Time Domain -- A.4 Components αβ0 on the Stationary Reference Frame -- A.5 Components dq0 on the Synchronous Reference Frame -- Appendix B Instantaneous Power Theories -- B.1 Introduction -- B.2 Origin of Power Definitions at the Time Domain for Single-Phase Systems -- B.3 Origin of Active Currents in Multiphase Systems -- B.4 Instantaneous Calculation of Power Currents in Multiphase Systems -- B.5 The p-q Theory -- B.6 Generalization of the p-q Theory to Arbitrary Multiphase Systems.

B.7 The Modified p-q Theory -- B.8 Generalized Instantaneous Reactive Power Theory for Three-Phase Power Systems -- B.9 Summary -- Appendix C Resonant Controller -- C.1 Introduction -- C.2 Internal Model Principle -- C.3 Equivalence of the PI Controller in the dq Frame and the P+Resonant Controller in the αβ Frame -- Index.