Power Electronics Design: A Practitioner’s Guide Power Electronics Design: A Practitioner’s Guide Keith H. Sueker AMSTERDAM • BOSTON • HEIDELBERG • LONDON NEW YORK • OXFORD • PARIS • SAN DIEGO SAN FRANCISCO • SINGAPORE • SYDNEY • TOKYO Newnes is an imprint of Elsevier Newnes is an imprint of Elsevier 30 Corporate Drive, Suite 400, Burlington, MA 01803, USA Linacre House, Jordan Hill, Oxford OX2 8DP, U K Copyright © 2005, SciTech Publishing Inc. 911 Paverstone Dr., Ste. B Raleigh, NC 27615 www.scitechpub.com All rights reserved. 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, or otherwise, without the prior written permission of the publisher. Permissions may be sought directly from Elsevier’s Science & Technology Rights Department in Oxford, UK: phone: (+44) 1865 843830, fax: (+44) 1865 853333, e-mail: permissions@elsevier.com.uk. You may also complete your request online via the Elsevier homepage (http://www.elsevier.com), by selecting “Customer Support” and then “Obtaining Permissions.” Tables 14.4 and 14.5 reprinted with permission from IEEE Std. 519-1992– Recommended Practices and Requirements for Harmonic Control in Electrical Power Systems, Copyright 1996 © , by IEEE. The IEEE disclaims any responsibility or liability resulting from the placement and use in the described manner. Recognizing the importance of preserving what has been written, Elsevier prints its books on acid-free paper whenever possible. Library of Congress Cataloging-in-Publication Data Sueker, Keith H. Power electronics design : a practitioner's guide / by Keith H. Sueker.—1st ed. p. cm. Includes bibliographical references and index. ISBN 0-7506-7927-1 (hardcover : alk. paper) 1. Power electronics—Design and construction. I. Title. TK7881.15.S84 2005 621.31'7 dc22 2005013673 British Library Cataloguing-in-Publication Data A catalogue record for this book is available from the British Library. ISBN: 0-7506-7946-8 For information on all Newnes publications visit our website at www.books.elsevier.com 050607080910 10987654321 Printed in the United States of America v Contents List of Figures. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xi List of Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xvii Preface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xix Chapter 1 Electric Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1 1.1 AC versus DC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1 1.2 Pivotal Inventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3 1.3 Generation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4 1.4 Electric Traction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5 1.5 Electric Utilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6 1.6 In-Plant Distribution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11 1.7 Emergency Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12 Chapter 2 Power Apparatus . . . . . . . . . . . . . . . . . . . . . . . . . . . .15 2.1 Switchgear. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15 2.2 Surge Suppression. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19 2.3 Conductors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21 2.4 Capacitors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25 2.5 Resistors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 2.6 Fuses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31 2.7 Supply Voltages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32 vi Contents 2.8 Enclosures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32 2.9 Hipot, Corona, and BIL. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33 2.10 Spacings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34 2.11 Metal Oxide Varistors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35 2.12 Protective Relays. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37 Chapter 3 Analytical Tools. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39 3.1 Symmetrical Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39 3.2 Per Unit Constants. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41 3.3 Circuit Simulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43 3.4 Circuit Simulation Notes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45 3.5 Simulation Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47 Chapter 4 Feedback Control Systems . . . . . . . . . . . . . . . . . . . . .49 4.1 Basics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49 4.2 Amplitude Responses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50 4.3 Phase Responses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53 4.4 PID Regulators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54 4.5 Nested Control Loops . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56 Chapter 5 Transients . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57 5.1 Line Disturbances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57 5.2 Circuit Transients . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .58 5.3 Electromagnetic Interference . . . . . . . . . . . . . . . . . . . . . . . . . . .61 Chapter 6 Traveling Waves . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65 6.1 Basics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65 6.2 Transient Effects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68 6.3 Mitigating Measures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .71 Chapter 7 Transformers and Reactors . . . . . . . . . . . . . . . . . . . .73 7.1 Transformer Basics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .74 7.2 Construction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .78 7.3 Insulation Systems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .82 7.4 Basic Insulation Level. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .84 7.5 Eddy Current Effects. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .85 7.6 Interphase Transformers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .89 7.7 Transformer Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .90 7.8 Reactors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .93 Contents vii 7.9 Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97 7.10 Cooling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .97 7.11 Instrument Transformers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .98 Chapter 8 Rotating Machines . . . . . . . . . . . . . . . . . . . . . . . . . .101 8.1 Direct Current Machines. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .101 8.2 Synchronous Machines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .103 8.3 Induction (Asynchronous) Machines . . . . . . . . . . . . . . . . . . . . 107 8.4 NEMA Designs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110 8.5 Frame Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .111 8.6 Linear Motors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .112 Chapter 9 Rectifiers and Converters. . . . . . . . . . . . . . . . . . . . .115 9.1 Early Rectifiers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .115 9.2 Mercury Vapor Rectifiers . . . . . . . . . . . . . . . . . . . . . . . . . . . . .116 9.3 Silicon Diodes—The Semiconductor Age . . . . . . . . . . . . . . . .117 9.4 Rectifier Circuits—Single-Phase . . . . . . . . . . . . . . . . . . . . . . .118 9.5 Rectifier Circuits—Multiphase. . . . . . . . . . . . . . . . . . . . . . . . . 120 9.6 Commutation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .123 Chapter 10 Phase Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125 10.1 The SCR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .126 10.2 Forward Drop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .131 10.3 SCR Circuits—AC Switches . . . . . . . . . . . . . . . . . . . . . . . . . .131 10.4 SCR Motor Starters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .135 10.5 SCR Converters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .137 10.6 Inversion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .139 10.7 Gate Drive Circuits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .142 10.8 Power to the Gates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .145 10.9 SCR Autotapchangers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145 10.10 SCR DC Motor Drives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .148 10.11 SCR AC Motor Drives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .148 10.12 Cycloconverters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .150 Chapter 11 Series and Parallel Operation . . . . . . . . . . . . . . . .153 11.1 Voltage Sharing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .153 11.2 Current Sharing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158 11.3 Forced Sharing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .160 viii Contents Chapter 12 Pulsed Converters . . . . . . . . . . . . . . . . . . . . . . . . . .163 12.1 Protective Devices. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .163 12.2 Transformers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .164 12.3 SCRs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .166 Chapter 13 Switchmode Systems . . . . . . . . . . . . . . . . . . . . . . . .169 13.1 Pulse Width Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .169 13.2 Choppers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .173 13.3 Boost Converters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .174 13.4 The “H” Bridge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .175 13.5 High-Frequency Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . .178 13.6 Harmonic Injection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .179 13.7 Series Bridges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .180 Chapter 14 Power Factor and Harmonics . . . . . . . . . . . . . . . .181 14.1 Power Factor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .181 14.2 Harmonics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .184 14.3 Fourier Transforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .189 14.4 Interactions with the Utility. . . . . . . . . . . . . . . . . . . . . . . . . . . .194 14.5 Telephone Influence Factor. . . . . . . . . . . . . . . . . . . . . . . . . . . .199 14.6 Distortion Limits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .201 14.7 Zero-Switching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .202 Chapter 15 Thermal Considerations . . . . . . . . . . . . . . . . . . . . .203 15.1 Heat and Heat Transfer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .203 15.2 Air Cooling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .205 15.3 Water Cooling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .206 15.4 Device Cooling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .208 15.5 Semiconductor Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . .213 Chapter 16 Power Electronics Applications . . . . . . . . . . . . . . .215 16.1 Motor Drives and SCR Starters. . . . . . . . . . . . . . . . . . . . . . . . .215 16.2 Glass Industry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .217 16.3 Foundry Operations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .218 16.4 Plasma Arcs and Arc Furnaces . . . . . . . . . . . . . . . . . . . . . . . . .219 16.5 Electrochemical Supplies . . . . . . . . . . . . . . . . . . . . . . . . . . . . .219 16.6 Cycloconverters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .220 16.7 Extremely Low-Frequency Communications . . . . . . . . . . . . . .221 Contents ix 16.8 Superconducting Magnet Energy Storage . . . . . . . . . . . . . . . .222 16.9 600-kW Opamp. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .223 16.10 Ozone Generators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .223 16.11 Semiconductor Silicon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .224 16.12 VAR Compensators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .224 16.13 Induction Furnace Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . .225 16.14 Tokamaks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 226 16.15 Multi-tap Switching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .227 Appendix A Converter Equations . . . . . . . . . . . . . . . . . . . . . . .229 Appendix B Lifting Forces . . . . . . . . . . . . . . . . . . . . . . . . . . . . .231 Appendix C Commutation Notches and THDv . . . . . . . . . . . .233 Appendix D Capacitor Ratings . . . . . . . . . . . . . . . . . . . . . . . . .235 Appendix E Rogowski Coils . . . . . . . . . . . . . . . . . . . . . . . . . . . .237 Appendix F Foreign Technical Words . . . . . . . . . . . . . . . . . . .239 Appendix G Aqueous Glycol Solutions . . . . . . . . . . . . . . . . . . .241 Appendix H Harmonic Cancellation with Phase Shifting . . . .243 Appendix I Neutral Currents with Nonsinusoidal Loads . . . .245 Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 247 [...]... PE Consulting Engineer Pittsburgh, PA Chapter 1 Electric Power Relative to the digital age, the electric utility industry may seem old hat But power electronics and the power industry have a growing symbiotic relationship Nearly all power electronics systems draw power from the grid, and utility companies benefit from the application of power electronics to motor drives and to converters used for high-voltage... In this book, I have defined power electronics as the application of high -power semiconductor technology to large motor drives, power supplies, power conversion equipment, electric utility auxiliaries, and a host of other applications It provides an overview of material no longer taught in most college electrical engineering curricula, and it contains a wealth of practical design information It is also... system My intended audience is design engineers, design drafters, and technicians now working in the power electronics industry Students studying in two- and four-year electrical engineering and engineering technology programs, advanced students seeking a ready reference, and engineers working in other industries but with a need to know some essential aspects of power electronics will all find the book... transients, and semiconductors, to name but a few The attendees were design engineers, sales engineers, technicians, and drafters The tutorials were designed to present an overview of the power electronics field as well as design information for the engineers They were very well received and appreciated The material was useful to design engineers, but the technicians, drafters, and sales engineers appreciated... Tesla, employed by Westinghouse The first designs were for two-phase power, although three-phase designs soon followed Three-phase transmission was preferred, because it minimized the amount of copper required to transmit a given amount of power The simple, rugged induction motor was quickly put into production and was the key to utilizing AC 4 1 ◊ Electric Power power by industry The induction motor required... month per power factor adjusted peak kilowatt demand This charge supports the transformers, transmission lines, and distribution system necessary to deliver the power The power factor adjustment recognizes the fact that it is amperes that really matter to the delivery system Demand charges often provide a powerful incentive for industrial 10 1 ◊ Electric Power customers to improve their power factor,... for the maximum voltage 1.7 Emergency Power There are three levels of reliability to consider for emergency power First, there is the power required for mandatory emergency exit signs and interior lighting in the event of a power outage This is often supplied from an engine generator set powered by natural gas with automatic starting in the event of an external power failure Battery backup may be used... turbines, coal or nuclear powered, and hydraulic turbines supply the vast majority of the motive power for generators, but natural gas fired combustion turbines are growing rapidly as environmental concerns limit additional coal and nuclear power Much lower levels of power are produced by wind farms, although this area is expanding as the art progresses Still lesser amounts of power are produced by reciprocating... the power electronics engineer 1.1 AC versus DC Take warning! Alternating currents are dangerous They are fit only for powering the electric chair The only similarity between an a-c and a d-c lighting system is that they both start from the same coal pile And thus did Thomas Edison try to discourage the growing use of alternating-current electric power that was competing with his DC 1 2 1 ◊ Electric Power. .. book covering design considerations that are not obvi- xix xx Preface ous but are better not learned the hard way It presents an overview of the ancillary apparatus associated with power electronics as well as examples of potential pitfalls in the design process The book approaches these matters in a simple, directed fashion with a minimum reliance on calculus I have tried to put the overall design process . Power Electronics Design: A Practitioner’s Guide Power Electronics Design: A Practitioner’s Guide Keith H. Sueker AMSTERDAM. book, I have defined power electronics as the application of high -power semiconductor technology to large motor drives, power supplies, power conversion equipment,