Table Of ContentSecond Edition
Electrical
Energy
Systems
The ELECTRIC POWER ENGINEERING Series
Series Editor Leo L. Grigsby
Published Titles
Electric Drives
Ion Boldea and Syed Nasar
I/near Synchronous Motors: Transportation and Automation Systems
Jacek Gieras and Jerry Piech
Electromechanical Systems, Electric Machinesand Applied Mechatronics
t
Sergey E, Lyshevski
Electrical Energy Systems, Second Edition
Mohamad E. EI-Hawary
The Induction Machine Handbook
Ion Boldea and Syed Nasar
Power Quality
C. Sankaran
Power System Operations and Electricity Markets
Fred I. Denny and David E. Dismukes
Computational Methods for Electric Power Systems
Mariesa Crow
Electric Power Substations Engineering
John D. McDonald
Electric Power Transformer Engineering
James H, Harlow
Electric Power Distribution Handbook
Tom Short
Synchronous Generators
Ion Boldea
Variable Speed Generators
Ion Boldea
Harmonics and Power Systems
Francisco C, De La Rosa
Electric Machines
Charles A, Gross
Distribution System Modeling and Analysis, Second Edition
William H. Kersting
Second Edition
Electrical
Energy
Systems
Mohamed E. El-Ha wary
CRC Press
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Library of Congress Cataloging-in-Publication Data
El-Hawary, M. E.
Electrical energy systems / Mohamed E. El-Hawary. -- 2nd ed.
p. cm. -- (Electric power engineering series ; 16)
Includes bibliographical references and index.
ISBN 978-0-8493-9531-4 (alk. paper)
1. Electric power production. I. Title. II. Series.
TK1001.E36 2008
621.31--dc22 2007017630
A Library of Congress record exists under LC control number: 2007017630
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ISBN 13: 978-1-315-89253-5 (hbk)
ISBN 13: 978-1-351-07163-5 (ebk)
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Electrical Energy Systems v
PREFACE
The second edition of this book capitalizes on the many suggestions for
enhancements that I received from colleagues around the world. It is written
primarily as an introduction to electrical energy systems. It is intended for
students in Electrical and other engineering disciplines, as well as being useful
as a reference and self-study guide for the professional dealing with this
important area. The coverage of the book is designed to allow its use in a
number of ways including service courses taught to non-electrical majors. The
organization and details of the material in this book enables maximum flexibility
for the instructor to select topics to include in courses within the modern
engineering curriculum.
The book does not assume a level of mathematical awareness beyond
that given in undergraduate courses in basic physics and introductory electric
circuits. Emphasis is given to an improved appreciation of the operational
characteristics of the electrical apparatus discussed, on the basis of linear
mathematical models. Almost every key concept is illustrated through the use
of in-text examples that are worked out in detail to enforce the reader's
understanding. The text coverage includes some usage of MATLAB™ to solve
fundamental problems of basic performance characteristics to obtain analysis of
power system devices.
The first chapter in this book provides a historical perspective on the
development of electric power systems. While this topic is not an integral part
of the conventional coverage in texts and courses in this area, this chapter should
provide interesting insights into the influence of these developments on present
day civilization. It is through an appreciation of the past developments and
achievements that we can understand our present and forge ahead with future
advances.
Chapters 2 to 8 deal with fundamental topics to be covered in courses
in electric energy systems. Emphasis is given to practical aspects such as the
main performance characteristics of the devices discussed and system
applications. The importance of computer control in power system operations is
highlighted in Chapter 8 where we discuss the structure and functions involved
in a modern energy control center.
Chapter 9 is new to this book, and offers a brief discussion of the
Present and Future of Electric Energy Systems. Of specific interest is a
discussion of the challenges facing the system designer and operator in last of
the events of the first decade of the 21st century.
I have attempted to make this book as self-containing as possible. As a
result, the reader will find that many background topics such as the per unit
system and three-phase circuits are included in the text's main body as opposed
to the recent trend toward including many appendices dealing with these topics.
In studying and teaching electrical energy systems it has been my experience
Preface vi
that a problem solving approach is most effective in exploring this rich area.
A textbook such as this could not have been written without the
continuing input of the many students who have gone through many versions of
its material as it was developed. My sincere thanks to the members of the many
classes to whom I was privileged to teach this fascinating subject. I wish to
acknowledge the able work of Elizabeth Sanford of Dalhousie University in
putting this manuscript in a better form than I was able to produce. My
association with the CRC Press staff has been valuable throughout the many
stages of preparing this text. I wish to express my appreciation to Nora
Konopka for her continuous encouragement and support.
I owe a debt of gratitude to Dr. Leo Grigsby of Auburn University for
suggesting that I write the first edition of this book. As has always been the
case, the patience and understanding of my wife, Dr. Ferial El-Hawary, made
this project another joy to look forward to completing. It goes without saying
that our sons and daughter deserve a greater share of my appreciation for their
continuous understanding.
M.E. El-Hawary
Halifax, Nova Scotia
December 19, 2006
Electrical Energy Systems vii
Table of Contents
Preface
Chapter 1 - INTRODUCTION
1.1 A Brief History of Electric Power Systems 1
1.2 The Structure of the Power System 3
1.3 Outline of the Text 7
Chapter 2 - BASICS OF ELECTRIC ENERGY SYSTEM THEORY
2.1 Introduction 9
2.2 Concepts of Power in Alternating Current Systems 9
2.3 Three-Phase Systems 15
2.4 The Per Unit System 25
2.5 Electromagnetism and Electromechanical Energy
Conversion 28
2.6 Permeability and Magnetic Field Intensity 31
2.7 Flux Linkages, Induced Voltages, Inductance, and
Energy 34
2.8 Hysteresis Loop 36
2.9 Eddy Current and Core Losses 38
2.10 Energy Flow Approach 40
2.11 Multiply Excited Systems 44
2.12 Doubly Excited Systems 46
2.13 Salient-Pole Machines 47
2.14 Round or Smooth Air-Gap Machines 50
2.15 Machine-Type Classification 52
2.16 P-Pole Machines 55
2.17 Power System Representation 59
Problems 59
Chapter 3 - POWER GENERATION AND THE SYNCHRONOUS
MACHINE
3.1 Introduction 69
3.2 The Synchronous Machine: Preliminaries 69
3.3 Synchronous Machine Fields 72
3.4 A Simple Equivalent Circuit 74
3.5 Principal Steady-State Characteristics 77
3.6 Power-Angle Characteristics and the Infinite Bus
Concept 79
3.7 Accounting for Saliency 86
3.8 Salient-Pole Machine Power Angle Characteristics 91
Problems 93
Chapter 4 - THE TRANSFORMER
4.1 Introduction 99
4.2 General Theory of Transformer Operation 99
viii Table of Contents
4.3 Transformer Connections 113
Problems 123
Chapter 5 - ELECTRIC POWER TRANSMISSION
5.1 Introduction 129
5.2 Electric Transmission Line Parameters 129
5.3 Line Inductance 131
5.4 Line Capacitance 149
5.5 Two-Port Networks 165
5.6 Transmission Line Models 167
Problems 183
Chapter 6 - INDUCTION AND FRACTIONAL HORSEPOWER
MOTORS
6.1 Introduction 191
6.2 Three-Phase Induction Motors 191
6.3 Torque Relations 199
6.4 Classification of Induction Motors 204
6.5 Rotating Magnetic Fields in Single-Phase Induction
Motors 205
6.6 Equivalent Circuits for Single-Phase Induction
Motors 210
6.7 Power and Torque Relations 216
6.8 Starting Single-Phase Induction Motors 222
6.9 Single-Phase Induction Motor Types 224
Problems 231
Chapter 7 - FAULTS AND PROTECTION OF ELECTRIC ENERGY
SYSTEMS
7.1 Introduction 237
7.2 Transients during a Balanced Fault 238
7.3 The Method of Symmetrical Components 240
7.4 Sequence Networks 245
7.5 Line-to-Ground Fault 261
7.6 Double Line-to-Ground Fault 264
7.7 Line-to-Line Fault 268
7.8 The Balanced Three-Phase Fault 271
7.9 System Protection, An Introduction 272
7.10 Protective Relays 273
7.11 Transformer Protection 276
7.12 Transmission Line Protection 282
7.13 Impedance-Based Protection Principles 289
7.14 Computer Relaying 297
Problems 299
Chapter 8 - THE ENERGY CONTROL CENTER
8.1 Introduction 305
8.2 Overview of EMS Functions 307
Electrical Energy Systems
8.3 Power Flow Control 315
8.4 Power Flow 319
8.5 Stability Considerations 332
8.6 Power System State Estimation 340
8.7 Power System Security 344
8.8 Contingency Analysis 349
8.9 Optimal Preventive and Corrective Actions 354
8.10 Dynamic Security Analysis 361
Chapter 9 - THE PRESENT AND FUTURE OF ELECTRIC ENERGY
SYSTEMS
9.1 Introduction 367
9.2 Challenges Facing the System 367
9.3 Blackouts and their Impact 371
9.4 Mitigating and Coping 379
REFERENCES 385
INDEX 391
