Control of Electric Machine Drive Systems Seung-Ki Sul
Control of Electric Machine Drive Systems
IEEE Press 445 Hoes Lane Piscataway, NJ 08854 IEEE Press Editorial Board Lajos Hanzo, Editor in Chief R. Abari M. El-Hawary S. Nahavandi J. Anderson B. M. Hammerli W. Reeve F. Canavero M. Lanzerotti T. Samad T. G. Croda O. Malik G. Zobrist Kenneth Moore, Director of IEEE Book and Information Services (BIS)
Control of Electric Machine Drive Systems Seung-Ki Sul
Copyright Ó 2011 by the Institute of Electrical and Electronics Engineers, Inc. Published by John Wiley & Sons, Inc., Hoboken, New Jersey. All rights reserved. Published simultaneously in Canada No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, scanning, or otherwise, except as permitted under Section 107 or 108 of the 1976 United States Copyright Act, without either the prior written permission of the Publisher, or authorization through payment of the appropriate per-copy fee to the Copyright Clearance Center, Inc., 222 Rosewood Drive, Danvers, MA 01923, (978) 750-8400, fax (978) 750-4470, or on the web at www.copyright.com. Requests to the Publisher for permission should be addressed to the Permissions Department, John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030, (201) 748-6011, fax (201) 748-6008, or online at http://www.wiley.com/go/ permission. Limit of Liability/Disclaimer of Warranty: While the publisher and author have used their best efforts in preparing this book, they make no representations or warranties with respect to the accuracy or completeness of the contents of this book and specifically disclaim any implied warranties of merchantability or fitness for a particular purpose. No warranty may be created or extended by sales representatives or written sales materials. The advice and strategies contained herein may not be suitable for your situation. You should consult with a professional where appropriate. Neither the publisher nor author shall be liable for any loss of profit or any other commercial damages, including but not limited to special, incidental, consequential, or other damages. For general information on our other products and services or for technical support, please contact our Customer Care Department within the United States at (800) 762-2974, outside the United States at (317) 572-3993 or fax (317) 572-4002. Wiley also publishes its books in a variety of electronic formats. Some content that appears in print may not be available in electronic formats. For more information about Wiley products, visit our web site at www.wiley.com. Library of Congress Cataloging-in-Publication Data: Sul, Seung-Ki. Control of electric machine drive system / Seung-Ki Sul. p. cm. (IEEE Press series on power engineering ; 55) Includes bibliographical references. Summary: This book is based on the author s industry experience. It contains many exercise problems that engineers would experience in their day-to-day work. The book was published in Korean at 500 pages as a textbook. The book will contain over 300 figures. Provided by publisher. Summary: This book is based on the author s industry experience. It contains many exercise problems that engineers would experience in their day-to-day work Provided by publisher. ISBN 978-0-470-59079-9 (hardback) 1. Electric driving Automatic control. I. Title. TK4058.S8513 2011 621.46 dc22 2010039507 Printed in the United States of America ebook: 978-0-470-87655-8 obook: 978-0-470-87654-1 10 9 8 7 6 5 4 3 2 1
To my father, who lived his whole life as an unknown engineer.
Contents Preface xiii 1 Introduction 1 1.1 Introduction 1 1.1.1 Electric Machine Drive System 4 1.1.2 Trend of Development of Electric Machine Drive System 5 1.1.3 Trend of Development of Power Semiconductor 7 1.1.4 Trend of Development of Control Electronics 8 1.2 Basics of Mechanics 8 1.2.1 Basic Laws 9 1.2.2 Force and Torque 9 1.2.3 Moment of Inertia of a Rotating Body 11 1.2.4 Equations of Motion for a Rigid Body 13 1.2.5 Power and Energy 17 1.2.6 Continuity of Physical Variables 18 1.3 Torque Speed Curve of Typical Mechanical Loads 18 1.3.1 Fan, Pump, and Blower 18 1.3.2 Hoisting Load; Crane, Elevator 20 1.3.3 Traction Load (Electric Vehicle, Electric Train) 21 1.3.4 Tension Control Load 23 Problems 24 References 35 2 Basic Structure and Modeling of Electric Machines and Power Converters 36 2.1 Structure and Modeling of DC Machine 36 2.2 Analysis of Steady-State Operation 41 2.2.1 Separately Excited Shunt Machine 42 2.2.2 Series Excited DC Machine 45 2.3 Analysis of Transient State of DC Machine 46 2.3.1 Separately Excited Shunt Machine 47 2.4 Power Electronic Circuit to Drive DC Machine 50 2.4.1 Static Ward Leonard System 51 2.4.2 Four-Quadrants Chopper System 52 2.5 Rotating Magnetic Motive Force 53 2.6 Steady-State Analysis of a Synchronous Machine 58 vii
viii Contents 2.7 Linear Electric Machine 62 2.8 Capability Curve of Synchronous Machine 63 2.8.1 Round Rotor Synchronous Machine with Field Winding 63 2.8.2 Permanent Magnet Synchronous Machine 64 2.9 Parameter Variation of Synchronous Machine 66 2.9.1 Stator and Field Winding Resistance 66 2.9.2 Synchronous Inductance 66 2.9.3 Back EMF Constant 67 2.10 Steady-State Analysis of Induction Machine 70 2.10.1 Steady-State Equivalent Circuit of an Induction Machine 72 2.10.2 Constant Air Gap Flux Operation 77 2.11 Generator Operation of an Induction Machine 79 2.12 Variation of Parameters of an Induction Machine 81 2.12.1 Variation of Rotor Resistance, R r 81 2.12.2 Variation of Rotor Leakage Inductance, L lr 82 2.12.3 Variation of Stator Resistance, R s 82 2.12.4 Variation of Stator Leakage Inductance, L ls 83 2.12.5 Variation of Excitation Inductance, L m 84 2.12.6 Variation of Resistance Representing Iron Loss, R m 84 2.13 Classification of Induction Machines According to Speed Torque Characteristics 84 2.14 Quasi-Transient State Analysis 87 2.15 Capability Curve of an Induction Machine 88 2.16 Comparison of AC Machine and DC Machine 90 2.16.1 Comparison of a Squirrel Cage Induction Machine and a Separately Excited DC Machine 90 2.16.2 Comparison of a Permanent Magnet AC Machine and a Separately Excited DC Machine 92 2.17 Variable-Speed Control of Induction Machine Based on Steady-State Characteristics 92 2.17.1 Variable Speed Control of Induction Machine by Controlling Terminal Voltage 93 2.17.2 Variable Speed Control of Induction Machine Based on Constant Air-Gap Flux ( V = F) Control 94 2.17.3 Variable Speed Control of Induction Machine Based on Actual Speed Feedback 95 2.17.4 Enhancement of Constant Air-Gap Flux Control with Feedback of Magnitude of Stator Current 96 2.18 Modeling of Power Converters 96 2.18.1 Three-Phase Diode/Thyristor Rectifier 97 2.18.2 PWM Boost Rectifier 98 2.18.3 Two-Quadrants Bidirectional DC/DC Converter 101 2.18.4 Four-Quadrants DC/DC Converter 102 2.18.5 Three-Phase PWM Inverter 103 2.18.6 Matrix Converter 105 2.19 Parameter Conversion Using Per Unit Method 106 Problems 108 References 114
Contents ix 3 Reference Frame Transformation and Transient State Analysis of Three-Phase AC Machines 116 3.1 Complex Vector 117 3.2 d q n Modeling of an Induction Machine Based on Complex Space Vector 119 3.2.1 Equivalent Circuit of an Induction Machine at d q n AXIS 120 3.2.2 Torque of the Induction Machine 125 3.3 d q n Modeling of a Synchronous Machine Based on Complex Space Vector 128 3.3.1 Equivalent Circuit of a Synchronous Machine at d q n AXIS 128 3.3.2 Torque of a Synchronous Machine 138 3.3.3 Equivalent Circuit and Torque of a Permanent Magnet Synchronous Machine 140 3.3.4 Synchronous Reluctance Machine (SynRM) 144 Problems 146 References 153 4 Design of Regulators for Electric Machines and Power Converters 154 4.1 Active Damping 157 4.2 Current Regulator 158 4.2.1 Measurement of Current 158 4.2.2 Current Regulator for Three-Phase-Controlled Rectifier 161 4.2.3 Current Regulator for a DC Machine Driven by a PWM Chopper 166 4.2.4 Anti-Wind-Up 170 4.2.5 AC Current Regulator 173 4.3 Speed Regulator 179 4.3.1 Measurement of Speed/Position of Rotor of an Electric Machine 179 4.3.2 Estimation of Speed with Incremental Encoder 182 4.3.3 Estimation of Speed by a State Observer 189 4.3.4 PI/IP Speed Regulator 198 4.3.5 Enhancement of Speed Control Performance with Acceleration Information 204 4.3.6 Speed Regulator with Anti-Wind-Up Controller 206 4.4 Position Regulator 208 4.4.1 Proportional Proportional and Integral (P PI) Regulator 208 4.4.2 Feed-Forwarding of Speed Reference and Acceleration Reference 209 4.5 Detection of Phase Angle of AC Voltage 210 4.5.1 Detection of Phase Angle on Synchronous Reference Frame 210 4.5.2 Detection of Phase Angle Using Positive Sequence Voltage on Synchronous Reference Frame 213 4.6 Voltage Regulator 215 4.6.1 Voltage Regulator for DC Link of PWM Boost Rectifier 215 Problems 218 References 228
x Contents 5 Vector Control 230 5.1 Instantaneous Torque Control 231 5.1.1 Separately Excited DC Machine 231 5.1.2 Surface-Mounted Permanent Magnet Synchronous Motor (SMPMSM) 233 5.1.3 Interior Permanent Magnet Synchronous Motor (IPMSM) 235 5.2 Vector Control of Induction Machine 236 5.2.1 Direct Vector Control 237 5.2.2 Indirect Vector Control 243 5.3 Rotor Flux Linkage Estimator 245 5.3.1 Voltage Model Based on Stator Voltage Equation of an Induction Machine 245 5.3.2 Current Model Based on Rotor Voltage Equation of an Induction Machine 246 5.3.3 Hybrid Rotor Flux Linkage Estimator 247 5.3.4 Enhanced Hybrid Estimator 248 5.4 Flux Weakening Control 249 5.4.1 Constraints of Voltage and Current to AC Machine 249 5.4.2 Operating Region of Permanent Magnet AC Machine in Current Plane at Rotor Reference Frame 250 5.4.3 Flux Weakening Control of Permanent Magnet Synchronous Machine 257 5.4.4 Flux Weakening Control of Induction Machine 262 5.4.5 Flux Regulator of Induction Machine 267 Problems 269 References 281 6 Position/Speed Sensorless Control of AC Machines 283 6.1 Sensorless Control of Induction Machine 286 6.1.1 Model Reference Adaptive System (MRAS) 286 6.1.2 Adaptive Speed Observer (ASO) 291 6.2 Sensorless Control of Surface-Mounted Permanent Magnet Synchronous Machine (SMPMSM) 297 6.3 Sensorless Control of Interior Permanent Magnet Synchronous Machine (IPMSM) 299 6.4 Sensorless Control Employing High-Frequency Signal Injection 302 6.4.1. Inherently Salient Rotor Machine 304 6.4.2 AC Machine with Nonsalient Rotor 305 Problems 317 References 320 7 Practical Issues 324 7.1 Output Voltage Distortion Due to Dead Time and Its Compensation 324 7.1.1 Compensation of Dead Time Effect 325
Contents xi 7.1.2 Zero Current Clamping (ZCC) 327 7.1.3 Voltage Distortion Due to Stray Capacitance of Semiconductor Switches 327 7.1.4 Prediction of Switching Instant 330 7.2 Measurement of Phase Current 334 7.2.1 Modeling of Time Delay of Current Measurement System 334 7.2.2 Offset and Scale Errors in Current Measurement 337 7.3 Problems Due to Digital Signal Processing of Current Regulation Loop 342 7.3.1 Modeling and Compensation of Current Regulation Error Due to Digital Delay 342 7.3.2 Error in Current Sampling 346 Problems 350 References 353 Appendix A Measurement and Estimation of Parameters of Electric Machinery 354 A.1 Parameter Estimation 354 A.1.1 DC Machine 355 A.1.2 Estimation of Parameters of Induction Machine 357 A.2 Parameter Estimation of Electric Machines Using Regulators of Drive System 361 A.2.1 Feedback Control System 361 A.2.2 Back EMF Constant of DC Machine, K 363 A.2.3 Stator Winding Resistance of Three-Phase AC Machine, R s 363 A.2.4 Induction Machine Parameters 365 A.2.5 Permanent Magnet Synchronous Machine 370 A.3 Estimation of Mechanical Parameters 374 A.3.1 Estimation Based on Mechanical Equation 374 A.3.2 Estimation Using Integral Process 376 References 380 Appendix B d q Modeling Using Matrix Equations 381 B.1 Reference Frame and Transformation Matrix 381 B.2 d q Modeling of Induction Machine Using Transformation Matrix 386 B.3 d q Modeling of Synchronous Machine Using Transformation Matrix 390 Index 391 IEEE Press Series on Power Engineering 401
Preface It has been eight years since my book, Control Theory of Electric Machinery, was published in Korean. In the past six years, more than 2500 copies of the book have been sold in Korea. Some of them are used as a textbook for a graduate course at several universities in Korea. But most of them are used as a reference book in the industry. After publishing the book in Korean, I received a lot of encouragement and inquiry to translate the book into English. But my tight schedule has delayed the translation. However, four years ago, several foreign students and visitors attended my graduate course class and they need some study materials so I was forced to translate the book into English. After two years of hard work, the English-version manuscript is now ready for publication. During the translation, the contents of this book was revised and upgraded. I hope that this book will be a good reference for the students and engineers in the field. Modern technology, which today is called information technology, is based on the stable supply of energy, especially electric energy which is the most widely used. Many people in modern society think that electric energy can be produced for as long as we want. However, because clean water and air are growing scarce, electric energy comes to us as a very limited resource. As modern society develops, more and more electric energy is needed. But mass production, transportation, and use of environmentally friendly electric energy have become a very difficult problem. Electric energy goes through various steps of transformation from production to final use. Mechanical energy acquired from a primary energy source such as oil, gas, nuclear, and hydraulic power can be converted to electric energy through electromechanical energy conversion. More precisely, after mechanical energy from various sources is transformed to electric energy through a generator, voltage and frequency are controlled for proper purpose, and in developed countries, more than 60% of energy is transformed into mechanical energy again for later use. Hence, in the whole process of production and consumption of electric energy, the most critical fields of engineering are efficient control of voltage/current and frequency and appropriate control of electric machines. For 30 years my academic interest has been the control of electric machinery and I have dedicated myself to research and development of this field. This book has been written to share these experiences with my colleagues. Even small research results cannot be achieved alone and I owe this book to the efforts of many others. First of all, I mention my academic advisor for Master s and Ph.D. courses taken at Seoul National University, Professor Minho Park, who opened my path in the field of power electronics and control of electric machines. Second, I recognize my honored professor and at the same time my father-in-law, Jongsoo xiii