Understanding Power Quality Problems - Voltage Sags and Interruptions

Power quality problems have increasingly become a substantial concern over the last decade, but surprisingly few analytical techniques have been developed to overcome these disturbances in system-equipment interactions. Now in this comprehensive book, power engineers and students can find the theoretical background necessary for understanding how to analyze, predict, and mitigate the two most severe power disturbances: voltage sags and interruptions. This is the first book to offer in-depth analysis of voltage sags and interruptions and to show how to apply mathematical techniques for practical solutions to these disturbances. From UNDERSTANDING AND SOLVING POWER QUALITY PROBLEMS you will gain important insights into Various types of power quality phenomena and power quality standards Current methods for power system reliability evaluation Origins of voltage sags and interruptions Essential analysis of voltage sags for characterization and prediction of equipment behavior and stochastic prediction Mitigation methods against voltage sags and interruptions Sponsored by:IEEE Power Electronics Society, IEEE Industry Applications Society, IEEE Power Engineering Society.Table of Content PREFACE xiii FTP SITE INFORMATION xv ACKNOWLEDGMENTS xvii CHAPTER 1 Overview of Power Quality and Power Quality Standards 1 1.1 Interest in Power Quality 2 1.2 Power Quality, Voltage Quality 4 1.3 Overview of Power Quality Phenomena 6 1.4 Power Quality and EMC Standards 22 CHAPTER 2 Long Interruptions and Reliability Evaluation 35 2.1 Introduction 35 2.2 Observation of System Performance 37 2.3 Standards and Regulations 48 2.4 Overview of Reliability Evaluation 50 2.5 Basic Reliability Evaluation Techniques 62 2.6 Costs of Interruptions 101 2.7 Comparison of Observation and Reliability Evaluation 106 2.8 Example Calculations 107 CHAPTER 3 Short Interruptions 115 3.1 Introduction 115 3.2 Terminology 115 3.3 Origin of Short Interruptions 116 3.4 Monitoring of Short Interruptions 121 3.5 Influence on Equipment 125 3.6 Single-Phase Tripping 127 3.7 Stochastic Prediction of Short Interruptions 136 CHAPTER 4 Voltage Sags—Characterization 139 4.1 Introduction 139 4.2 Voltage Sag Magnitude 140 4.3 Voltage Sag Duration 168 4.4 Three-Phase Unbalance 174 4.5 Phase-Angle Jumps 198 4.6 Magnitude and Phase-Angle Jumps for Three-Phase Unbalanced Sags 206 4.7 Other Characteristics of Voltage Sags 231 4.8 Load Influence on Voltage Sags 238 4.9 Sags due to Starting of Induction Motors 248 CHAPTER 5 Voltage Sags—Equipment Behavior 253 5.1 Introduction 253 5.2 Computers and Consumer Electronics 256 5.3 Adjustable-Speed AC Drives 265 5.4 Adjustable-Speed DC Drives 300 5.5 Other Sensitive Load 318 CHAPTER 6 Voltage Sags—Stochastic Assessment 325 6.1 Compatibility between Equipment and Supply 325 6.2 Presentation of Results: Voltage Sag Coordination Chart 328 6.3 Power Quality Monitoring 342 6.4 The Method of Fault Positions 359 6.5 The Method of Critical Distances 373 CHAPTER 7 Mitigation of Interruptions and Voltage Sags 389 7.1 Overview of Mitigation Methods 389 7.2 Power System Design—Redundancy Through Switching 397 7.3 Power System Design—Redundancy through Parallel Operation 405 7.4 The System-Equipment Interface 419 CHAPTER 8 Summary and Conclusions 453 8.1 Power Quality 453 8.2 Standardization 455 8.3 Interruptions 456 8.4 Reliability 457 8.5 Characteristics of Voltage Sags 458 8.6 Equipment Behavior due to Voltage Sags 459 8.7 Stochastic Assessment of Voltage Sags 460 8.8 Mitigation Methods 462 8.9 Final Remarks 462 BIBLIOGRAPHY 465 APPENDIX A Overview of EMC Standards 477 APPENDIX B IEEE Standards on Power Quality 481 APPENDIX C Power Quality Definitions and Terminology 485 APPENDIX D List of Figures 507 APPENDIX E List of Tables 525 INDEX 529 ABOUT THE AUTHOR 543Biographical Note Math H. J. Bollen is associate professor in the Department of Electric Power Engineering at Chalmers University of Technology, Gothenburg, Sweden. Before joining Chalmers, he was employed as a lecturer at the University of Manchester Institute of Technology (UMIST), Manchester, UK and at Eindhoven University of Technology, Eindhoven, The Netherlands. In 1998 Dr. Bollen received the ABB Energy Prize (Gunnar Engström Stipendiet) for his work on power quality and his contributions toward understanding voltage sags. He is cochair of the IEEE Industry Applications Society Power System Reliability Subcommittee and is active in a number of other working groups on power quality and reliability. Electrical Engineering / Power Understanding Power Quality Problems Voltage Sags and Interruptions Power quality problems have become an increasing concern over the last decade, but surprisingly few analytical techniques have been developed to overcome these disturbances in system-equipment interactions. Now in this comprehensive book, power engineers and students can find the theoretical background necessary for understanding how to analyze, predict, and mitigate the two most severe disturbances: voltage sags and interruptions. This is the first book to offer an in-depth analysis of voltage sags and interruptions, and to show how to apply mathematical techniques for practical solutions to these disturbances. From Understanding Power Quality Problems you will gain important insights into: Various types of power quality phenomena and power quality standards Current methods for power system reliability evaluation Origins of voltage sags and interruptions Essential analysis of voltage sags for characterization and prediction of equipment behavior and stochastic prediction Mitigation methods against voltage sags and interruptions