Electrical Machine Drives Control: An Introduction
()
About this ebook
Key features:
* Provides a comprehensive summary of all aspects of controlled-speed electrical drive technology including control and operation.
* Handling of electrical drives is solidly linked to the theory and design of the associated electrical machines. Added insight into problems and functions are illustrated with clearly understandable figures.
* Offers an understanding of the main phenomena associated with electrical machine drives.
* Considers the problem of bearing currents and voltage stresses of an electrical drive.
* Includes up-to-date theory and design guidelines, taking into account the most recent advances.
This book’s rigorous coverage of theoretical principles and techniques makes for an excellent introduction to controlled-speed electrical drive technologies for Electrical Engineering MSc or PhD students studying electrical drives. It also serves as an excellent reference for practicing electrical engineers looking to carry out design, analyses, and development of controlled-speed electrical drives.
Related to Electrical Machine Drives Control
Related ebooks
Variable Speed AC Drives with Inverter Output Filters Rating: 0 out of 5 stars0 ratingsAnalysis of Electric Machinery and Drive Systems Rating: 0 out of 5 stars0 ratingsAC Electric Motors Control: Advanced Design Techniques and Applications Rating: 0 out of 5 stars0 ratingsSubstation Automation Systems: Design and Implementation Rating: 5 out of 5 stars5/5Programmable Logic Controllers: A Practical Approach to IEC 61131-3 using CoDeSys Rating: 0 out of 5 stars0 ratingsPower Quality: Problems and Mitigation Techniques Rating: 5 out of 5 stars5/5Theory on DC Electric Circuits Rating: 0 out of 5 stars0 ratingsDesign of Rotating Electrical Machines Rating: 5 out of 5 stars5/5Simulation of Some Power Electronics Case Studies in Matlab Simpowersystem Blockset Rating: 2 out of 5 stars2/5Foundations of Electromagnetic Compatibility: with Practical Applications Rating: 0 out of 5 stars0 ratingsPower Electronics and Electric Drives for Traction Applications Rating: 0 out of 5 stars0 ratingsHandbook of Power Systems Engineering with Power Electronics Applications Rating: 0 out of 5 stars0 ratingsEnergy-saving Principles and Technologies for Induction Motors Rating: 0 out of 5 stars0 ratingsFluid Power Rating: 2 out of 5 stars2/5IEC 61131-3 Second Edition Rating: 0 out of 5 stars0 ratingsIntroductory Circuits Rating: 3 out of 5 stars3/5Programmable Logic Controllers A Complete Guide - 2020 Edition Rating: 0 out of 5 stars0 ratingsDictionary of Industrial Terms Rating: 0 out of 5 stars0 ratingsMotion control A Complete Guide Rating: 0 out of 5 stars0 ratingsThe PLC Programming Guide for Beginners Rating: 0 out of 5 stars0 ratingsProgrammable Logic Controllers Rating: 4 out of 5 stars4/5SCADA supervisory control and data acquisition Third Edition Rating: 0 out of 5 stars0 ratingsTransients of Modern Power Electronics Rating: 0 out of 5 stars0 ratingsPLC Programming from Novice to Professional: Learn PLC Programming with Training Videos Rating: 5 out of 5 stars5/5Plant Maintenance Engineer: Passbooks Study Guide Rating: 0 out of 5 stars0 ratingsMultisensor Instrumentation 6σ Design: Defined Accuracy Computer-Integrated Measurement Systems Rating: 0 out of 5 stars0 ratingsBasic Electricity and Electronics for Control: Fundamentals and Applications 3rd Edition Rating: 4 out of 5 stars4/5High Performance Control of AC Drives with Matlab / Simulink Models Rating: 0 out of 5 stars0 ratingsHMI A Complete Guide - 2021 Edition Rating: 0 out of 5 stars0 ratingsSCADA A Complete Guide - 2020 Edition Rating: 0 out of 5 stars0 ratings
Science & Mathematics For You
A Letter to Liberals: Censorship and COVID: An Attack on Science and American Ideals Rating: 3 out of 5 stars3/5Feeling Good: The New Mood Therapy Rating: 4 out of 5 stars4/5Outsmart Your Brain: Why Learning is Hard and How You Can Make It Easy Rating: 4 out of 5 stars4/5The Big Book of Hacks: 264 Amazing DIY Tech Projects Rating: 4 out of 5 stars4/5Ultralearning: Master Hard Skills, Outsmart the Competition, and Accelerate Your Career Rating: 4 out of 5 stars4/5Becoming Cliterate: Why Orgasm Equality Matters--And How to Get It Rating: 4 out of 5 stars4/5The Gulag Archipelago [Volume 1]: An Experiment in Literary Investigation Rating: 4 out of 5 stars4/5The Big Fat Surprise: Why Butter, Meat and Cheese Belong in a Healthy Diet Rating: 4 out of 5 stars4/5Other Minds: The Octopus, the Sea, and the Deep Origins of Consciousness Rating: 4 out of 5 stars4/5Homo Deus: A Brief History of Tomorrow Rating: 4 out of 5 stars4/5The Systems Thinker: Essential Thinking Skills For Solving Problems, Managing Chaos, Rating: 4 out of 5 stars4/5The Dorito Effect: The Surprising New Truth About Food and Flavor Rating: 4 out of 5 stars4/5A Crack In Creation: Gene Editing and the Unthinkable Power to Control Evolution Rating: 4 out of 5 stars4/5The Psychology of Totalitarianism Rating: 4 out of 5 stars4/5The Wisdom of Psychopaths: What Saints, Spies, and Serial Killers Can Teach Us About Success Rating: 4 out of 5 stars4/5Memory Craft: Improve Your Memory with the Most Powerful Methods in History Rating: 3 out of 5 stars3/5The Rise of the Fourth Reich: The Secret Societies That Threaten to Take Over America Rating: 4 out of 5 stars4/5How Emotions Are Made: The Secret Life of the Brain Rating: 4 out of 5 stars4/5No-Drama Discipline: the bestselling parenting guide to nurturing your child's developing mind Rating: 4 out of 5 stars4/5Oppenheimer: The Tragic Intellect Rating: 5 out of 5 stars5/5Lies My Gov't Told Me: And the Better Future Coming Rating: 4 out of 5 stars4/5The Gulag Archipelago: The Authorized Abridgement Rating: 4 out of 5 stars4/5Activate Your Brain: How Understanding Your Brain Can Improve Your Work - and Your Life Rating: 4 out of 5 stars4/5Free Will Rating: 4 out of 5 stars4/5On Food and Cooking: The Science and Lore of the Kitchen Rating: 5 out of 5 stars5/5Hunt for the Skinwalker: Science Confronts the Unexplained at a Remote Ranch in Utah Rating: 4 out of 5 stars4/5Born for Love: Why Empathy Is Essential--and Endangered Rating: 4 out of 5 stars4/5The Hungry Brain: Outsmarting the Instincts That Make Us Overeat Rating: 4 out of 5 stars4/5The Trouble With Testosterone: And Other Essays On The Biology Of The Human Predi Rating: 4 out of 5 stars4/5
Reviews for Electrical Machine Drives Control
0 ratings0 reviews
Book preview
Electrical Machine Drives Control - Juha Pyrhonen
CONTENTS
Cover
Title Page
Copyright
Preface
Abbreviations and Symbols
Chapter 1: Introduction to Electrical Machine Drives Control
1.1 What is an Electrical Machine Drive?
1.2 Controlled Variable Speed Drives
1.3 Electrical Machine Drive Implementation
1.4 Controlled Electrical Drives and Energy Efficiency
1.5 The Electrical Drive as an Element of a Controlled Industrial Process
References
Chapter 2: Aspects Common to All Controlled Electrical Machine Drive Types
2.1 Pulse Width Modulation Converter Electrical Motor Drive
2.2 Converter Interface to Power Source
2.3 Fundamental Mechanics
2.4 Basic Mechanical Load Types
2.5 Proportional-Integral-Derivative Controller in Electrical Drives
2.6 The Speed, Torque, or Position Control of an Electrical Drive
2.7 Control Time Rates and Embedded System Principles
2.8 Per-Unit Values
Chapter 3: The Fundamentals of Electric Machines
3.1 Energy Conversion in Electric Machines
3.2 Industrial Machine Windings
3.3 Effective Winding Turns and Spatial Harmonics
3.4 Induction Machine Rotors
3.5 The Damper Winding
3.6 AC Winding Systems
3.7 DC Machine Windings
3.8 The Brushless DC Machine
3.9 The Magnetic Circuit of an Electric Machine
3.10 Motor Voltage, Flux Linkage, Flux, Field Weakening, and Voltage Reserve
3.11 Motors in Power-Electronic Electrical Drives
References
Chapter 4: The Fundamentals of Space-Vector Theory
4.1 Introduction to the Space Vector for Current Linkage
4.2 Space-Vector Equivalent Circuits and the Voltage-Vector Equations
4.3 Space-Vector Model in the General Reference Frame
4.4 The Two-Axis Model
4.5 Application of Space-Vector Theory
References
Chapter 5: Torque and Force Production and Power
5.1 The Lorentz Force
5.2 The General Equation for Torque
5.3 Power
5.4 Reluctance Torque and Co-Energy
5.5 Reluctance Torque and the Cross-Field Principle in a Rotating Field Machine
5.6 Maxwell's Stress Tensor in the Definition of Torque
References
Chapter 6: Basic Control Principles for Electric Machines
6.1 The Control of a DC Machine
6.2 AC Machine Control Basics
6.3 Vector Control of AC Motors
6.4 Direct Flux-Linkage Control and Direct Torque Control
6.5 Improving DFLC to Achieve DTC
6.6 Other Control Principles
References
Chapter 7: DC and AC Power Electronic Topologies – Modulation for the Control of Rotating-Field Motors
7.1 The Thyristor Bridge as a Power-Electronic Drive Component
7.2 The Cycloconverter
7.3 The Load Commutated Inverter Drive
7.4 Voltage Source Inverter Power Stages
7.5 The Matrix Converter
7.6 Multilevel Inverters
7.7 The Structure and Interfaces of a Frequency Converter
References
Chapter 8: Synchronous Electrical Machine Drives
8.1 Synchronous Machine Drives for Power Generation
8.2 Synchronous Motor Drives
8.3 Synchronous Machine Models
8.4 Equivalent Circuits and Machine Parameters for a Synchronous Machine
8.5 Measuring Motor Parameters Using a Frequency Converter
8.6 Finite Element Analysis (FEA) for Determining the Synchronous Machine Inductances
8.7 The Relationship between the Stator and Rotor Excitations for a Synchronous Machine
8.8 The Vector Diagram for a Synchronous Machine
8.9 Torque Production for a Synchronous Machine
8.10 Simulating an Electrically Excited Salient-Pole Machine via Constant Parameters
8.11 The Current Equations for a Synchronous Machine
8.12 Simulating a Synchronous Machine in a Discrete-Time System
8.13 The Implementation of Vector Control for a Synchronous Machine
8.14 Field-Winding Current, Reactive Power, and the Dynamics of a Synchronous Machine Drive
8.15 The DOL Synchronous Machine and Field-Winding Current Supply
References
Chapter 9: Permanent Magnet Synchronous Machine Drives
9.1 PMSM Configurations and Machine Parameters
9.2 The Equivalent Circuit and Space-Vector Diagram for a PMSM
9.3 Equations Based on the Electric Current Angle
9.4 PMSM Current Vector Control
9.5 PMSM Direct Flux Linkage and Torque Control
9.6 Torque Estimation Accuracy in a PMSM DTC Drive
9.7 Speed and Position Sensorless Control Methods for PM Machines
References
Chapter 10: Synchronous Reluctance Machine Drives
10.1 The Operating Principle and Structure of a SynRM
10.2 Model, Space-Vector Diagram, and Basic Characteristics of a SynRM
10.3 The Control of a SynRM
10.4 Further Development of SynRM Drives – PMaSynRM
References
Chapter 11: Asynchronous Electrical Machine Drives
11.1 The Working Principle of the Induction Motor – Direct Online Drives
11.2 Asynchronous Machine Structures and the Main Norms
11.3 Frequency Converter Drives – Losses in a PWM Inverter Drive
11.4 Frequency Converter Control Methods for an Induction Motor
11.5 A summary of Industrial Induction Motor Drives
11.6 Doubly Fed Induction Machine Drives
Appendix IM1
References
Chapter 12: Switched Reluctance Machine Drives
12.1 The Torque or Force of an SR Machine
12.2 Average Torque
12.3 Control Systems for a SR Machine
12.4 The General Controller Structure
12.5 The Position Sensorless Operation of an SR Machine
12.6 A Summary of SR Drives
References
Chapter 13: Other Considerations: The Motor Cable, Voltage Stresses, and Bearing Currents
13.1 Cable Modelling
13.2 Reflected Voltage at a Cable Impedance Point of Discontinuity
13.3 Continuing Voltage at a Cable Impedance Point of Discontinuity
13.4 Motor Overvoltage
13.5 Limiting Overvoltages with Impedance Matching
13.6 Motor Bearing Currents in the Inverter Drive
13.7 Reducing Bearing Currents
References
Index
End User License Agreement
List of Tables
Table 1.1
Table 1.2
Table 3.1
Table 3.2
Table 4.1
Table 6.1
Table 7.1
Table 7.2
Table 7.3
Table 7.4
Table 7.5
Table 8.1
Table 8.2
Table 8.3
Table E8.1
Table E8.2
Table E8.3
Table E8.4
Table E8.5
Table 8.4
Table 8.5
Table 8.6
Table 8.7
Table 9.1
Table 9.2
Table 11.1
Table 11.2
Table 11.3
Table 11.4
Table 11.5
Table 11.6
List of Illustrations
Figure 1.1
Figure 1.2
Figure 1.3
Figure 1.4
Figure 2.1
Figure 2.2
Figure 2.3
Figure 2.4
Figure 2.5
Figure 2.6
Figure 2.7
Figure 2.8
Figure 2.9
Figure 2.10
Figure 2.11
Figure 2.12
Figure 3.1
Figure 3.2
Figure 3.3
Figure 3.4
Figure 3.5
Figure 3.6
Figure 3.7
Figure 3.8
Figure 3.9
Figure 3.10
Figure 3.11
Figure 3.12
Figure 3.13
Figure 3.14
Figure 3.15
Figure 3.16
Figure 3.17
Figure 3.18
Figure 3.19
Figure 3.20
Figure 3.21
Figure 3.22
Figure 3.23
Figure 4.1
Figure 4.2
Figure 4.3
Figure 4.4
Figure 4.5
Figure 4.6
Figure 4.7
Figure 4.8
Figure 4.9
Figure 4.10
Figure 4.11
Figure 4.12
Figure 4.13
Figure 4.14
Figure 4.15
Figure 4.16
Figure 4.17
Figure 5.1
Figure 5.2
Figure 5.3
Figure 5.4
Figure 5.5
Figure 5.6
Figure 5.7
Figure 5.8
Figure 6.1
Figure 6.2
Figure 6.3
Figure 6.4
Figure 6.5
Figure 6.6
Figure 6.7
Figure 6.8
Figure 6.9
Figure 6.10
Figure 6.11
Figure 6.12
Figure 6.13
Figure 6.14
Figure 6.15
Figure 6.16
Figure 6.17
Figure 6.18
Figure 6.19
Figure 6.20
Figure 6.21
Figure 6.22
Figure 6.23
Figure 6.24
Figure 7.1
Figure 7.2
Figure 7.3
Figure 7.4
Figure 7.5
Figure 7.6
Figure 7.7
Figure 7.8
Figure 7.9
Figure 7.10
Figure 7.11
Figure 7.12
Figure 7.13
Figure 7.14
Figure 7.15
Figure 7.16
Figure 7.17
Figure 7.18
Figure 7.19
Figure 7.20
Figure 7.21
Figure 7.22
Figure 7.23
Figure 7.24
Figure 7.25
Figure 7.26
Figure 7.27
Figure 7.28
Figure 7.29
Figure 7.30
Figure 7.31
Figure 7.32
Figure 7.33
Figure 7.34
Figure 7.35
Figure 7.36
Figure 7.37
Figure 7.38
Figure 7.39
Figure 7.40
Figure 7.41
Figure 7.42
Figure 7.43
Figure 7.44
Figure 7.45
Figure 7.46
Figure 7.47
Figure 7.48
Figure 8.1
Figure 8.2
Figure 8.3
Figure 8.4
Figure 8.5
Figure 8.6
Figure 8.7
Figure 8.8
Figure 8.9
Figure 8.10
Figure 8.11
Figure 8.12
Figure 8.13
Figure 8.14
Figure 8.15
Figure 8.16
Figure 8.17
Figure 8.18
Figure 8.19
Figure 8.20
Figure 8.21
Figure 8.22
Figure 8.23
Figure 8.24
Figure 8.25
Figure 8.26
Figure 8.27
Figure 8.28
Figure 8.29
Figure 8.30
Figure 8.31
Figure 8.32
Figure 8.33
Figure 8.34
Figure 8.35
Figure 8.36
Figure 8.37
Figure E8.1
Figure E8.2
Figure E8.3
Figure E8.4
Figure E8.5
Figure E8.6
Figure E8.7
Figure E8.8
Figure E8.9
Figure E8.10
Figure 8.38
Figure 8.39
Figure 8.40
Figure 8.41
Figure 8.42
Figure 8.43
Figure 8.44
Figure 8.45
Figure 8.46
Figure 8.47
Figure 8.48
Figure 8.49
Figure 8.50
Figure 8.51
Figure 8.52
Figure 8.53
Figure 8.54
Figure 8.55
Figure 8.56
Figure 8.57
Figure 8.58
Figure 8.59
Figure 8.60
Figure 8.61
Figure 8.62
Figure 8.63
Figure 8.64
Figure 8.65
Figure 8.66
Figure 8.67
Figure 8.68
Figure 8.69
Figure 8.70
Figure 8.71
Figure 8.72
Figure 8.73
Figure 8.74
Figure 9.1
Figure 9.2
Figure 9.3
Figure 9.4
Figure 9.5
Figure 9.6
Figure 9.7
Figure 9.8
Figure 9.9
Figure 9.10
Figure 9.11
Figure 9.12
Figure 9.13
Figure 9.14
Figure 9.15
Figure 9.16
Figure 9.17
Figure 9.18
Figure 9.19
Figure 9.20
Figure 9.21
Figure 9.22
Figure 9.23
Figure 9.24
Figure 9.25
Figure 9.26
Figure 9.27
Figure 9.28
Figure 9.29
Figure 9.30
Figure 9.31
Figure 10.1
Figure 10.2
Figure 10.3
Figure 10.4
Figure 10.5
Figure 10.6
Figure 10.7
Figure 10.8
Figure 10.9
Figure 10.10
Figure 10.11
Figure 10.12
Figure 10.13
Figure 10.14
Figure 10.15
Figure 10.16
Figure 11.1
Figure 11.2
Figure 11.3
Figure 11.4
Figure 11.5
Figure 11.6
Figure 11.7
Figure 11.8
Figure 11.9
Figure 11.10
Figure 11.11
Figure 11.12
Figure 11.13
Figure 11.14
Figure 11.15
Figure 11.16
Figure 11.17
Figure 11.18
Figure 11.19
Figure 11.20
Figure 11.21
Figure 11.22
Figure 11.23
Figure 11.24
Figure 11.25
Figure 11.26
Figure 11.27
Figure 11.28
Figure 11.29
Figure 11.30
Figure 11.31
Figure 11.32
Figure 11.33
Figure 11.34
Figure 11.35
Figure 11.36
Figure 11.37
Figure 11.38
Figure 11.39
Figure 11.40
Figure 11.41
Figure 11.42
Figure 11.43
Figure 11.44
Figure 11.45
Figure 11.46
Figure 11.47
Figure 11.48
Figure 11.49
Figure 11.50
Figure 11.51
Figure 11.52
Figure 11.53
Figure 11.54
Figure 11.55
Figure 11.56
Figure 11.57
Figure 11.58
Figure 11.59
Figure 11.60
Figure 11.61
Figure 11.62
Figure 11.63
Figure 12.1
Figure 12.2
Figure 12.3
Figure 12.4
Figure 12.5
Figure 12.6
Figure 12.7
Figure 12.8
Figure 12.9
Figure 12.10
Figure 12.11
Figure 12.12
Figure 12.13
Figure 12.14
Figure 12.15
Figure 13.1
Figure 13.2
Figure 13.3
Figure 13.4
Figure 13.5
Figure 13.6
Figure 13.7
Figure 13.8
Figure 13.9
Figure 13.10
Figure 13.11
Figure 13.12
Figure 13.13
Figure 13.14
Figure 13.15
Figure 13.16
Figure 13.17
Figure 13.18
Figure 13.19
Figure 13.20
Figure 13.21
Figure 13.22
Figure 13.23
Figure 13.24
Figure 13.25
Figure 13.26
Figure 13.27
Figure 13.28
Figure 13.29
Figure 13.30
Figure 13.31
Figure 13.32
Electrical Machine Drives Control
An Introduction
Juha Pyrhönen
Department of Electrical Engineering
Lappeenranta University of Technology, Finland
Valéria Hrabovcová
Faculty of Electrical Engineering
University of Žilina, Slovakia
R. Scott Semken
Department of Mechanical Engineering
Lappeenranta University of Technology, Finland
Wiley LogoThis edition first published 2016
© 2016 John Wiley & Sons Ltd
Registered office
John Wiley & Sons Ltd, The Atrium, Southern Gate, Chichester, West Sussex, PO19 8SQ, United Kingdom
For details of our global editorial offices, for customer services and for information about how to apply for permission to reuse the copyright material in this book please see our website at www.wiley.com.
The right of the authors to be identified as the authors of this work has been asserted in accordance with the Copyright, Designs and Patents Act 1988.
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, except as permitted by the UK Copyright, Designs and Patents Act 1988, without the prior permission of the publisher.
Wiley also publishes its books in a variety of electronic formats. Some content that appears in print may not be available in electronic books.
Designations used by companies to distinguish their products are often claimed as trademarks. All brand names and product names used in this book are trade names, service marks, trademarks or registered trademarks of their respective owners. The publisher is not associated with any product or vendor mentioned in this book.
Limit of Liability/Disclaimer of Warranty: While the publisher and authors 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. It is sold on the understanding that the publisher is not engaged in rendering professional services and neither the publisher nor the authors shall be liable for damages arising herefrom. If professional advice or other expert assistance is required, the services of a competent professional should be sought.
Library of Congress Cataloging-in-Publication Data
Names: Pyrhönen, Juha, author. | Hrabovcová, Valéria, author. | Semken, R. Scott, author.
Title: Electrical machine drives control : An introduction / Juha Pyrhönen, Valéria Hrabovcová, R. Scott Semken.
Description: Chichester, West Sussex, United Kingdom : John Wiley & Sons, Inc., [2016] | Includes bibliographical references and index.
Identifiers: LCCN 2016015388 | ISBN 9781119260455 (cloth) | ISBN 9781119260400 (epub) | ISBN 9781119260448 (epdf)
Subjects: LCSH: Electric driving. | Electric motors–Electronic control.
Classification: LCC TK4058 .P89 2016 | DDC 621.46–dc23 LC record available at https://lccn.loc.gov/2016015388
A catalogue record for this book is available from the British Library.
ISBN: 9781119260455
Preface
A basic study of electrical drives is fundamental to an electrical engineering curriculum, and, today, gaining a better academic understanding of the theory and application of controlled-velocity electrical drive technologies is increasingly important. Electrical drives provide superior control properties for a wide variety of processes, and the number of applications for precision-controlled motor drives is increasing. A modern electrical drive accurately controls motor torque and speed with relatively high electromechanical conversion efficiencies, making it possible to considerably reduce energy consumption. Because of the present pervasive use of electric machinery and the associated large energy flows, the introduction of more effective and efficient electrical drives promises significant environmental benefit, and electrical engineers are responding by introducing new and more efficient electrical drives to a myriad of industrial processes.
A controlled-velocity electrical drive combines power electronics, electric machinery, a control system, and drive mechanisms to apply force or torque to execute any number of desired functions. The term electric machinery refers primarily to the electromagnetic mechanical devices that convert electricity to mechanical power or mechanical power to electricity—that is, to electric motors or generators. The term control system refers to the control electronics, instrumentation, and coding that monitor the condition of the electric machinery and adjust operating speed and/or match force or torque to load.
With a rigorous introduction to theoretical principles and techniques, this academic reference and research book offers the master of science or doctoral student in electrical engineering a textbook that provides the background needed to carry out detailed analyses with respect to controlled-velocity electrical drives. At the same time, for engineers in general, the text can serve as a guide to understanding the main phenomena associated with electrical machine drives. The edition includes up-to-date theory and design guidelines, taking into account the most recent advances in the field. The years of scientific research activity and the extensive pedagogical skill of the authors have combined to produce this comprehensive approach to the subject matter. The considered electric machinery consists of not only classic rotating machines, such as direct current, asynchronous, and synchronous motors and generators, but also new electric machine architectures that have resulted as the controller and power electronics have continued to develop and as new materials, such as permanent magnets, have been introduced. Examples covered include permanent magnet synchronous machines, switched reluctance machines, and synchronous reluctance machines.
The text is comprehensive in its analysis of existing and emerging electrical drive technologies, and it thoroughly covers the variety of drive control methods. In comparison to other books in the field, this treatment is unique. The authors are experts in the theory and design of electric machinery. They clearly define the most basic electrical drive concepts and go on to explain the critical details while maintaining a solid connection to theory and design of the associated electric machinery. Addressing a number of industrial applications, the authors take their investigation of electrical drives beyond theory to examine a number of practical aspects of control and application. Scalar, vector, and direct torque control methods are thoroughly covered with the nonidealities of direct torque control being given particular focus.
The expert body of knowledge that makes up this book has been built up over a number of years with contributions from numerous colleagues from both the Lappeenranta University of Technology and the University of Žilina in Slovakia. The authors are grateful for their help.
In particular, the authors would like to thank Professor Tapani Jokinen for his extensive contributions in general, Professor Olli Pyrhönen for his expert guidance on the control of synchronous electrical machine drives, Dr. Pasi Peltoniemi for the detailed and valuable example on tuning the control of an electrically excited synchronous machine, and M.Sc. Juho Montonen for his permanent magnet machine analysis. The authors would also like to specifically thank Dr. Hanna Niemelä, who translated some of the included text from its original Finnish. Finally, we give our warmest thanks to our families, who accommodated our long hours of writing, editing, and manuscript preparation.
This academic reference and research book uniquely provides comprehensive materials concerning all aspects of controlled-velocity electrical drive technology including control and operation. The treatise is based on the authors' extensive expertise in the theory and design of electric machinery, and in contrast to existing publications, its handling of electrical drives is solidly linked to the theory and design of the associated electric machinery.
Abbreviations and Symbols
Subscripts
Superscripts
Boldface symbols are used for space vectors
1
Introduction to Electrical Machine Drives Control
Few technologies are more important to our collective quality of life than electrical drive technology. One could say that electric motors drive and electric generators power the world. Further, power electronics offers an indefatigable tool for accurate power conversion. And it seems the importance of the technology is poised to rise to even greater heights in the course of the next few decades as more reliable, more cost effective, and more flexible electrical drive systems become available.
For more than a century, electrical machine drives have been powering production processes for numerous industries. Applications include pumping, ventilation, compression, milling, crushing, grinding, conveying, and transporting. In modern robot-dependent manufacturing systems, electrical drives are responsible for precise position control of various robot arms and end effectors.
Concerns about air quality in cities and the increasing demand for improvements in energy efficiency favour using even more electric or hybrid vehicles for transportation needs. The current rate of change toward even more electromobility is limited only by today's high price of electric storage technology. The electrical drives themselves, that is, the motors and converters, are more than sufficient to serve as a replacement for the existing internal combustion engines in cars and buses.
Today, more than 50% of the world population lives in urban areas, and that percentage is growing. This growth in population powers increasing demand for more and better methods of moving people, materials, and things. Electrical machine drives are becoming an increasingly essential element of these transportation applications. Globalization, the accelerating process of international integration, puts added demand on sea and air transport, and ships and even aircraft are relying more and more on the most up-to-date electrical drive systems.
In addition, the average age of the world population is advancing at a rate unparalleled in human history. By 2050, the elderly will account for 16% of the global population. Caring for these 1.5 billion senior citizens over the age of 65 will strain the world's existing healthcare infrastructure. Fortunately, intelligent machinery has the potential to address the needs of the ageing population and to ease this demographic challenge. As the sinew of intelligent machinery, the increasing importance of electrical machines drives again seems to be clear.
Climate change is also bringing about ever more troubling environmental challenges. Permafrost in Siberia is melting and releasing methane into the atmosphere, there are stronger and increasingly damaging storms, and many drought areas are experiencing unprecedented levels of dryness. The burning of carbon-based fossil fuels to produce both electrical and motive power has been identified as a major contributor to climate change, and moving toward electrical power production technologies that do not burn fuels is a possible solution. Electrical generator drives are essential components of several of the more climate-friendly power production options currently available such as hydro, wind, and geothermal. Moreover, electric vehicles, a green alternative to fuel-burning cars, buses, and trucks, also rely on electrical motor drives.
At present, electric motors are the world's single biggest consumer of electricity, accounting for about 70% of industrial power consumption and nearly 45% of total global electricity consumption. Most in service are polyphase current (AC) induction motors, which are inexpensive and easy to maintain and can be directly connected to an AC power source. However, the majority of these AC induction motors lack flexible speed control, so they are not being used as efficiently as possible. Modern electrical drive technology is beginning to offer more cost-effective solutions with excellent speed control, making it possible to significantly improve efficiencies and minimize power consumption. These developments will encourage the replacement of AC motor systems in existing applications and the implementation of modern electrical drives for any new ones.
1.1 What is an Electrical Machine Drive?
The word drive comes from the Anglo-Saxon word dríf-an, which was a verb meaning to urge (an animal or person) to move. It is used as a noun here that can be defined as the means for giving motion to a machine or machine part. Therefore, an electrical drive can be defined as an electrical means of imparting motion. When an electrical drive is operated in reverse, it becomes a means of harnessing motion to generate electricity. To be more specific, when an electrical drive is driving, it can be referred to as an electrical motor drive. When it is driven, it can be referred to as an electrical generator drive.
Depending on the application, electric machines often operate in both motoring and generating modes. And, often, there is no technology difference between an electrical motor drive and an electrical generator drive. For example, the electric drive motor that propels an electric train or automobile—referred to as a traction motor—must run forward and backward and brake in both directions.
Electrical machine drives can be categorized as either noncontrolled or controlled motor or generator drives. Most motor drives working in industrial applications are noncontrolled. Almost exclusively, these are three-phase AC induction motors with direct on line (DOL) or across the line starting. Large-scale power generation mostly uses DOL drives based on synchronous generator drives.
To improve performance and efficiency, many applications are making use of controlled electrical drives. Controlled electrical motor drives are starting to become more popular in cases where the drives are tied into an industrial automation system. Distributed generation is driving demand in electrical power industries for speed-controlled electrical generator drives. In wind power, for example, so-called full power converters are becoming more common where both the generator and the network connection are fully controlled via power electronics.
1.2 Controlled Variable Speed Drives
The primary function of any variable speed drive is to control speed, force production, acceleration, deceleration, and direction of movement, whether it be rotary or linear. Unlike constant speed electric machines, variable speed drives can smoothly change speed to anywhere within their design operating range, and this adjustability makes it possible to optimize production processes for improved product quality, production speed, or safety.
Electrical variable speed drives are offered in a number of basic types, but the two most versatile for general purpose applications, and therefore the most common, are direct current (DC) drives and adjustable frequency AC drives. An electrical variable speed drive typically includes the following three principle elements.
The high-level controller enables (a) the operator to start, stop, and change speed via a human-machine interface (HMI) using buttons, switches, and potentiometers or (b) a plant control and set point master computer to send similar commands.
The drive controller converts the fixed voltage and frequency of an AC power source into adjustable power output to control the electric drive motor over its range of speeds.
The drive motor transforms electrical energy into motor movement. Shaft rotation or linear actuator movement speed varies with power applied by the drive controller.
1.2.1 DC Variable Speed Drives
DC drives are motor speed control systems based on DC motors or generators.
In a traditional rotary DC motor, the rotor (armature) spins inside a magnetic field that is initially produced either electromagnetically or via attached permanent magnets (PMs). The most common electromagnetic approach is to supply the field and armature windings separately. The result is referred to as a separately excited DC motor. If, instead, the no-load magnetic field is produced using PMs, the result is referred to as a PMDC motor. Separately excited and PMDC represent two of the more important and commonly used DC motor types.
In a separately excited and compensated DC motor, speed is directly proportional to the voltage applied to the armature and inversely proportional to motor flux, which is a function of field current. As a result, speed can be controlled via either armature voltage or field current. In a PMDC motor, speed is also directly proportional to the applied voltage. However, since the PMDC magnetic field remains constant, PMDC motor speed cannot be increased beyond the rated speed by reducing armature field current.
DC Drive Control
The speed and torque of a DC motor are independent. Speed is proportional to the applied voltage, and torque is proportional to the applied current.
As in all drives, power varies in direct proportion to speed. That is, 100% rated power is developed only at 100% rated motor speed with rated torque. Constant power over a specified speed range is needed for some applications. An armature-controlled DC drive can deliver less-than-maximum nearly constant power over a portion of its operating speed range. Because it is a function of speed, the level of power available depends on where in the speed range it is needed. For example, a particular drive might be capable of delivering 50% of its maximum power from 50% to 100% of its rated speed, so if 4 kW was needed over the upper half of the drives speed range, an armature-voltage–controlled drive rated for 8 kW would be required.
In addition to being armature-voltage controllable, the performance of separately excited DC drives can be influenced by changes in field current. Normally, they operate using a constant field excitation, but they can be pushed over their rated speed by reducing field flux beyond the rated speed point. This is called field weakening.
The Advantages of the DC Drive
Brushed DC motors are more complicated than AC motors and require more maintenance. Their most vulnerable component is the mechanical commutator, which acts as a mechanical inverter in a motor or a mechanical rectifier in a generator. The maximum speed of a DC motor depends on its mechanical endurance, which may be limited because of the commutator and brushes. Some of the disadvantages of the traditional DC motor can be overcome with a brushless DC motor architecture. The brushless DC motor moves the armature to the stator side and uses power-electronic commutation. Its architecture is similar to that of a PM synchronous AC motor.
The primary advantages can be summarized as follows.
DC drives can be less complex and less expensive for most power ratings.
DC drives can provide starting and accelerating torques exceeding 400% of rated (Sowmya, 2014).
DC drives are able to control speed over a wide range (above and below rated speed).
DC drives can be quick starting, stopping, reversing, and accelerating.
DC drives offer accurate speed control and a linear speed-torque curve.
DC drives dominate in sub-kilowatt power applications.
DC drives are easier to understand for maintenance and operations personnel.
1.2.2 AC Variable Speed Drives
AC drives are machine speed control systems based on AC motors or generators. AC motors typically operate using three-phase AC. Single-phase supplied AC induction motors are also widely used for lighter duty applications. The motors can be rotary or linear. In general, the controller characteristics are the same for either. For clarity, the following discussion focuses on rotary AC motor drives.
A rotary AC motor has a stationary stator and a spinning rotor. The stator is wound with a circular array of conductor coils (the windings) that produces static lines of current and a rotating magnetic field. The rotor carries lines of current that also produce a magnetic field. Both rotate as the rotor spins. The interaction between the rotor or stator currents and the common rotating magnetic field is responsible for the force production (torque) of the motor. Depending on motor type, the rotor currents may be produced via electromagnetic induction or via an active set of rotor windings. In a PM machine, the function of the stator is the same. However, the PM rotor lacks the lines of current and only contributes a spinning magnetic field. In analysis, the PM can be replaced by an equivalent current, if needed. The stator currents and the common rotating magnetic field are responsible for force production in a PM machine.
The two most common AC motor types are induction motors and synchronous motors, each with a number of variations.
The Induction Motor
An induction motor (also called an asynchronous motor) relies on a slight difference in speed between the rotating magnetic field of the stator and the rotating speed of the rotor to induce current in the rotor's AC windings or integral conductive squirrel cage. This difference in speed is referred to as slip.
Single-phase supplied AC induction motors are often two-phase capacitor-run motors. They can exhibit good performance properties for a particular working condition. Because induced coil currents produce a virtual second phase during operation, shaded-pole induction motors act like two-phase motors with their virtual second phase working as a short-circuit winding that produces a rotating field component in the air gap to start the motor. The single-phase motor types are not excellent performers. In general, they are not as efficient as multiple-phase induction motors; however, they are ubiquitous in both industrial and household settings, because of their simple construction, low cost, and reliability and because single-phase voltage sources are readily available. Single-phase frequency converters and small three-phase motors are available if speed-controllable single-phase motor drives are required. Naturally, this should be the trend to enhance energy efficiency.
Three-phase induction motors are the workhorses of industry. The two most common types use either active rotor windings or a rotor squirrel-cage architecture. Because in the first type AC current is transmitted to the active rotor windings via slip rings, it is commonly referred to as a slip-ring induction motor. The second type is referred to as a squirrel-cage induction motor.
Slip-ring induction motors equipped with external rotor resistors have high starting torque, smooth acceleration under heavy loads, adjustable speed, and good running characteristics. Traditionally, they have been used in applications such as lifts, cranes, and conveyors. More recently, their general popularity and market share have dropped off significantly. However, the doubly fed induction generator, a slip-ring machine, remains the most popular generator type for wind turbines. Squirrel-cage induction motors are simpler and rugged in construction. They are relatively inexpensive and require little maintenance. They are the preferred choice for lathes, drilling machines, pumps, and compressors, among other applications.
The Synchronous Motor
In contrast to the induction motor, a synchronous motor does not rely on slip induction. The magnetic poles of its rotor remain magnetically locked with the rotating air-gap magnetic field, which is synchronous with the frequency of the AC supply current. In a synchronous motor, the rotor poles are produced via an active set of windings or a circular array of PMs.
Synchronous motors are available with power ratings from less than 1 kW to tens of megawatts. Typically, sub-kilowatt synchronous motors are used in applications where a precise constant speed is needed, such as in clocks, timers, and tape players. Above 10 kW, the main benefits of synchronous motors are their high efficiency and an ability to provide power-factor correction. Larger synchronous motors can be found in higher-powered fans and blowers. Three-phase synchronous motors are also being used as traction motors for electric vehicles. The best-known example of synchronous traction motor use in an electric vehicle is France's high-speed TGV trains (for Train à Grande Vitesse, which is French for high-speed train
). The largest synchronous motor drive is the ABB-supplied 101-MW wind tunnel drive motor owned and operated by the USA National Aeronautics and Space Administration (NASA).
AC Drive Control
There are various methods used to transform incoming AC power into the adjustable form of input needed to control AC motor speed and torque. Two well-known examples are pulse-width modulation (PWM) and six-step or trapezoidal waveform conversion.
PWM varies the average value of voltage (and current) by rapidly switching (on and off) the voltage input to the motor. The relative duration of the on and off periods, referred to as the duty cycle, determines the amount of voltage supplied. Long on periods and short off periods correspond to high voltage, and short on periods and long off periods correspond to low voltage. Duty cycle is expressed in percentage with 100% being maximum voltage. PWM assumes inductive loads. With inductance, energy can be stored within the magnetic circuit to maintain relatively smooth current in response to the PWM supply.
For an AC drive to operate smoothly in response to PWM, the motor must receive on-off switching pulses that are short relative to the time it takes for the load to respond. The PWM resultant waveform must appear smooth to the load. Typically, AC drive switching frequencies can be from a few to tens of kHz.
Power Electronics (Switching Devices)
To implement the appropriate power conversion method (to vary