Grid Converters for Photovoltaic and Wind Power Systems

by Teodorescu, Remus; Liserre, Marco; Rodriguez , Pedro

• ISBN13: 9780470057513
• ISBN10: 0470057513
• Edition: 1st
• Format: Hardcover
• Copyright: 2011-02-21
• Publisher: Wiley-IEEE Press

Summary

This book provides a detailed coverage of power converters for renewable energy systems, so that power produced from these systems can be efficiently integrated into the national grid. The authors cover some general concepts in control theory, explaining different types of controller. Following this, the text goes on to analyse firstly the control of grid converters for photovoltaic, and then wind power systems, looking at system fundamentals, and more specific system control such as maximum point power tracking (MPPT), grid synchronization and monitoring methods, and grid requirement issues. Next, is a more general discussion of grid filters required by grid-connected distributed power generation systems (DPGS), and the interaction between grid converters and the grid. The final chapter examines some new auxiliary functions that may be implemented in DPGS in the future, in order to ensure stability as more power generated by these systems is integrated. Throughout the text, the authors include practical examples, exercises, and simulation models, and an accompanying website sets out further modelling the techniques using Matlab and Simulink environments, and PSIM software.

Author Biography

Remus Teodorecsu is currently an Associate Professor at the Institute of Technology, Aalborg University, teaching courses in power electronics and electrical energy system control for masters and PhD students. He has authored over 80 journal and conference papers, and one book Power Electronics: Computer Simulations (Technical Press Budapest, 1997), and also holds 3 patents. He is the founder and coordinator of the Green Power Laboratory at Aalborg University, focusing on the development and testing of grid converters for renewable energy systems, and is also co-recipient of the Technical Committee Prize Paper Awards at IEEE IAS Annual Meeting 1998, and IEEE Optim 2002. His research interests are in the design and control of power converters used in renewable energy systems, distributed generation, computer simulations and digital control implementation.

Marco Liserre is currently Assistant Professor at the Bari Polytechnic, Italy, teaching courses in basic and advanced power electronics, and industrial electronics. His research interests are in the control of power converters and drives, power quality, and distributed generation, and he has authored 70 papers on these subjects, 13 of them having been published in international journals. He has worked towards several projects funded by the Italian government and has also lectured at Aalborg University, Delft University, and at the Warsaw University of Technology. He is Editor of the Newsletter of the Industrial Electronic Society, and Associate Editor of the IEEE Transactions on Industrial Electronics.

Frede Blaabjerg is a Professor in the Power Electronics and Drives department at the Institute of Technology, Aalborg University, and also a part-time Research Leader at the Research Centre, Risoe, Denmark. His research areas are in power electronics, static power converters, adjustable speed drives, power semiconductor devices and simulation, wind turbines and green power inverters. He is the author and co-author of over 300 journal and conference papers, and is involved in more than 15 research projects within industry. Since 2001, he has been a member of the Danish Academy of Technical Science, and in 1998 he received the Outstanding Young Power Electronics Engineer Award from the IEEE Power Electronics Society. He has received 5 IEEE prize paper awards during the last seven years, the Statoil prize in 2003 and the Grundfos prize in 2004.

Table of Contents

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.