Computational methods for large sparse power systems analysis : an object oriented approach

473 Pages·2002·36.71 MB·English

by  S A Soman, S A Khaparde, Shubha Pandit

POWER QUALITY ENHANCEMENT
USING CUSTOM POWER DEVICES
THE KLUWER INTERNATIONAL SERIES
IN ENGINEERING AND COMPUTER SCIENCE
Power Electronics and Power Systems
Series Editor
M. A. Pai
Other books in the series:
COMPUTATIONAL METHODS FOR LARGE SPARSE POWER SYSTEMS ANALYSIS:
An Object Oriented Approach, S. A. Soman, S. A. Khaparde and Shubha Pandit,
ISBN 0-7923-7591-2
VALUATION, HEDGING AND SPECULATION IN COMPETITIVE ELECTRICITY
MARKETS: A Fundamental Approach, Petter L. Skantze and Marija D. IIic,
ISBN 0-7923-7528-9
OPERATION OF RESTRUCTURED POWER SYSTEMS, Kankar Bhattacharya, Math H. 1.
Bollen and Jaap E. Daalder, ISBN 0-7923-7397-9
TRANSIENT STABILITY OF POWER SYSTEMS: A Unified Approach to Assessment and
Control, Mania Pavella, Damien Ernst and Daniel Ruiz-Vega, ISBN 0-7923-7963-2
MAINTENANCE SCHEDULING IN RESTRUCTURED POWER SYSTEMS,
M. Shahidehpour and M. Marwali, ISBN 0·7923-7872-5
POWER SYSTEM OSCILLATIONS, Graham Rogers, ISBN 0-7923-7712-5
STATE ESTIMATION IN ELECTRIC POWER SYSTEMS: A Generalized Approach,
A. Monticelli, ISBN 0-7923-8519-5
COMPUTATIONAL AUCTION MECHANISMS FOR RESTRUCTURED POWER
INDUSTRY OPERATIONS, Gerald B. Sheble, ISBN 0-7923-8475-X
ANALYSIS OF SUBSYNCHRONOUS RESONANCE IN POWER SYSTEMS, K. R.
Padiyar, ISBN 0-7923-8319-2
POWER SYSTEMS RESTRUCTURING: Engineering and Economics, Marija Hic,
Francisco Galiana and Lester Fink, ISBN 0-7923-8163-7
CRYOGENIC OPERATION OF SILICON POWER DEVICES, Ranbir Singh and B. Jayant
Baliga, ISBN 0-7923-8157-2
VOLTAGE STABILITY OF ELECTRIC POWER SYSTEMS, Thierry Van Cutsem and
Costas Vournas, ISBN 0-7923-8139-4
AUTOMATIC LEARNING TECHNIQUES IN POWER SYSTEMS, Louis A. Wehenkel,
ISBN 0-7923-8068-1
ENERGY FUNCTION ANALYSIS FOR POWER SYSTEM STABILITY, M. A. Pai,
ISBN 0-7923-9035-0
ELECTROMAGNETIC MODELLING OF POWER ELECTRONIC CONVERTERS,
1. A. Ferreira, ISBN 0-7923-9034-2
MODERN POWER SYSTEMS CONTROL AND OPERATION, A. S. Debs,
ISBN 0-89838-265-3
RELIABILITY ASSESSMENT OF LARGE ELECTRIC POWER SYSTEMS, R. Billington,
R. N. Allan, ISBN 0-89838-266-1
SPOT PRICING OF ELECTRICITY, F. C. Schweppe, M. C. Caramanis, R. D. Tabors,
R. E. Bohn, ISBN 0-89838-260-2
INDUSTRIAL ENERGY MANAGEMENT: Principles and Applications, Giovanni Petrecca,
ISBN 0-7923-9305-8
THE FIELD ORIENTATION PRINCIPLE IN CONTROL OF INDUCTION MOTORS,
Andrzej M. Trzynadlowski, ISBN 0-7923-9420-8
FINITE ELEMENT ANALYSIS OF ELECTRICAL MACHINES, S. 1. Salon,
ISBN 0-7923 9594-8
POWER QUALITY ENHANCEMENT
USING CUSTOM POWER DEVICES
by
Arindam Ghosh
Indian Institute of Technology
Gerard Ledwich
Queensland University of Technology
KLUWER ACADEMIC PUBLISHERS
Boston / Dordrecht / London
Distributors for North, Central and South America:
Kluwer Academic Publishers
101 Philip Drive
Assinippi Park
Norwell, Massachusetts 02061 USA
Telephone [phone]
Fax [phone]
E-Mail:
Dedicated to my father Bholanath and the memory of my loving
mother Arati.
Arindam Ghosh
I dedicate this book in memory of my father Harry and give thanks
to God for His continued blessings.
Gerard Ledwich
Contents
Acknowledgements XIX
1 Introduction 1
I. I ELECTRIC POWER QUALITY 3
1. 1.1 Impacts of Power Quality Problems on End Users 4
1.1.2 Power Quality Standards 6
1.1.3 Power Quality Monitoring 7
1.2 POWER ELECTRONIC ApPLICATIONS IN POWER
TRANSMISSION SYSTEMS 8
1.2.1 HYDC Transmission 8
1.2.2 HYDC Light 9
1.2.3 Static Var Compensator (SVC) 10
1.2.4 Thyristor Controlled Series Compensator (TCSC) 12
1.2.5 Static Compensator (ST AT COM) 14
1.2.6 Static Synchronous Series Compensator (SSSC) 16
1.2.7 Unified Power Flow Controller (UPFC) 16
1.2.8 Other FACTS Devices 17
1.3 POWER ELECTRONIC ApPLICATIONS IN POWER
DISTRIBUTION SYSTEMS 18
1.4 DISTRIBUTED GENERATION 22
1.5 REFERENCES 23
VIII Contents
2 Characterization of Electric Power Quality 27
2.1 POWER QUALITY TERMS AND DEFINITIONS 29
2.1.1 Transients 29
2.1.2 Short Duration Voltage Variations 33
2.1.3 Long Duration Voltage variations 35
2.1.4 Voltage Imbalance 36
2.1.5 Waveform Distortion 36
2.1.6 Voltage Fluctuations 39
2.1.7 Power Frequency Variations 39
2.1.8 Power Acceptability Curves 39
2.2 POWER QUALITY PROBLEMS 40
2.2.1 Poor Load Power Factor 41
2.2.2 Loads Containing Harmonics 42
2.2.3 Notching in Load Voltage 45
2.2.4 DC Offset in Loads 45
2.2.5 Unbalanced Loads 46
2.2.6 Disturbance in Supply Voltage 52
2.3 CONCLUSIONS 53
2.4 REFERENCES 54
3 Analysis and Conventional Mitigation Methods 55
3 .1 ANALYSIS OF POWER OUTAGES 55
3.2 ANALYSIS OF UNBALANCE 60
3.2.1 Symmetrical Components of Phasor Quantities 60
3.2.2 Instantaneous Symmetrical Components 64
3.2.3 Instantaneous Real and Reactive Powers 67
3.3 ANALYSIS OF DISTORTION 72
3.3.1 On-line Extraction of Fundamental Sequence
Components from Measured Samples 76
3.3.2 Harmonic Indices 84
3 .4 ANALYSIS OF VOLTAGE SAG 86
3.4.1 Detroit Edison Sag Score 88
3.4.2 Voltage Sag Energy 88
3.4.3 Voltage Sag Lost Energy Index (VSLEI) 88
3.5 ANALYSIS OF VOLTAGE FLICKER 90
3.6 REDUCED DURATION AND CUSTOMER IMPACT OF OUTAGES 92
3.7 CLASSICAL LOAD BALANCING PROBLEM 93
3.7.1 Open-Loop Balancing 94
3.7.2 Closed-Loop balancing 98
3.7.3 Current Balancing 102
3.8 HARMONIC REDUCTION 104
3.9 VOLTAGE SAG OR DIP REDUCTION 108
Contents IX
3.10 CONCLUSIONS 110
3.11 REFERENCES 111
4 Custom Power Devices: An Introduction 113
4.1 UTILITy-CUSTOMER INTERFACE 114
4.2 INTRODUCTION TO CUSTOM POWER DEVICES 116
4.2.1 Network Reconfiguring Devices 117
4.2.2 Load Compensation using DST A TCOM 121
4.2.3 Voltage Regulation using DST A TCOM 126
4.2.4 Protecting Sensitive Loads using DVR 127
4.2.5 Unified Power Quality Conditioner (UPQC) 130
4.3 CUSTOM POWER PARK 131
4.4 STATUS OF ApPLICATION OF CP DEVICES 134
4.5 CONCLUSIONS 136
4.6 REFERENCES 136
5 Structure and Control of Power Converters 137
5.1 INVERTER TOPOLOGY 138
5.1.1 Single-Phase H-Bridge Inverter 138
5 .1.2 Three-Phase Inverter 143
5.2 HARD-SWITCHED VERSUS SOFT-SWITCHED 146
5.3 HIGH VOLTAGE INVERTERS 153
5.4 COMBINING INVERTERS FOR INCREASED POWER
AND VOLTAGE 154
5.4.1 Multi-Step Inverter 155
5.4.2 Multilevel Inverter 162
5.4.3 Chain Converter 167
5.5 OPEN-Loop VOLTAGE CONTROL 169
5.5.1 Sinusoidal PWM for H-Bridge Inverter 169
5.5.2 Sinusoidal PWM for three-phase Inverter 174
5.5.3 SPWM in Multilevel Inverter 175
5.5.4 Space Vector Modulation 178
5.5.5 Other Modulation Techniques 180
5.6 CLOSED-Loop SWITCHING CONTROL 182
5.6.1 Closed-Loop Modulation 182
5.6.2 Stability of Switching Control 183
5.6.3 Sampled Error Control 185
5.6.4 Hysteresis Control 187
5.7 SECOND AND HIGHER ORDER SYSTEMS 188
5.7.1 Sliding Mode Controller 192
5.7.2 Linear Quadratic Regulator (LQR) 193
5.7.3 Tracking Controller Convergence 195
x Contents
5.7.4 Condition for Tracking Reference Convergence 198
5.7.5 Deadbeat Controller 200
5.7.6 Pole Shift Controller 202
5.7.7 Sequential Linear Quadratic Regulator (SLQR) 203
5.8 CONCLUSIONS 210
5.9 REFERENCES 212
6 Solid State Limiting, Breaking and Transferring Devices 215
6.1 SOLID STATE CURRENT LIMITER 216
6.1.1 Current Limiter Topology 216
6.1.2 Current Limiter Operating Principle 217
6.2 SOLID STATE BREAKER (SSB) 220
6.3 ISSUES IN LIMITING AND SWITCHING OPERATIONS 223
6.4 SOLID STATE TRANSFER SWITCH (SSTS) 225
6.5 SAG/SWELL DETECTION ALGORITHMS 232
6.5.1 Algorithm Based on Symmetrical Components 232
6.5.2 Algorithm Based on Two-Axis Transformation 233
6.5.3 Algorithm Based on Instantaneous Symmetrical
Components 234
6.6 CONCLUSIONS 238
6.7 REFERENCES 239
7 Load Compensation using DSTATCOM 241
7.1 COMPENSATING SINGLE-PHASE LOADS 242
7.2 IDEAL THREE-PHASE SHUNT COMPENSATOR STRUCTURE 245
7.3 GENERATING REFERENCE CURRENTS USING
INSTANTANEOUS PQ THEORY 249
7 .4 GENERATING REFERENCE CURRENTS USING
INSTANTANEOUS SYMMETRICAL COMPONENTS 259
7.4.1 Compensating Star Connected Loads 260
7.4.2 Compensating Delta Connected Loads 265
7.5 GENERAL ALGORITHM FOR GENERATING REFERENCE
CURRENTS 268
7.5.1 Variolls Compensation Schemes and Their
Characteristics Based on the General Algorithm 269
7.5.2 Discussion of Results 270
7.6 GENERATING REFERENCE CURRENTS WHEN THE
SOURCE IS UNBALANCED 276
7.6.1 Compensating to Equal Resistance 278
7.6.2 Compensating to Equal Source Currents 280
7.6.3 Compensating to Equal Average Power 282
7.7 CONCLUSIONS 285
Contents XI
7.8 REFERENCES 285
8 Realization and Control of DSTA TCOM 287
8.1 DSTA TCOM STRUCTURE 288
8.2 CONTROL OF DST A TCOM CONNECTED TO A STIFF SOURCE 291
8.3 DSTA TCOM CONNECTED TO WEAK SUPPLY POINT 296
8.3.1 DSTATCOM Structure for Weak Supply Point
Connection 299
8.3.2 Switching Control of DSTA TCOM 302
8.3.3 DC Capacitor Control 308
8.4 DSTATCOM CURRENT CONTROL THROUGH PHASORS 310
8.4.1 Case-I: When Both Load and Source are Unbalanced 311
8.4.2 Case-2: When Both Load and Source are Unbalanced
and Load Contains Harmonics 313
8.4.3 Case-3: Both Load and Source are Unbalanced and
Di~orted 314
8.4.4 DC Capacitor Control 319
8.5 DSTATCOM IN VOLTAGE CONTROL MODE 321
8.5.1 State Feedback Control of DSTATCOM in
Voltage Control Mode 322
8.5.2 Output Feedback Control of DSTATCOM in
Voltage Control Mode 327
8.6 CONCLUSIONS 330
8.7 REFERENCES 330
9 Series Compensation of Power Distribution System 333
9.1 RECTIFIER SUPPORTED DVR 335
9.2 DC CAPACITOR SUPPORTED DVR 340
9.2.1 Fundamental Frequency Series Compensator
Characteristics 341
9.2.2 Transient Operation of Series Compensator when
the Supply is Balanced 346
9.2.3 Transient Operation when the Supply is Unbalanced
or Distorted 348
9.2.4 Series Compensator Rating 350
9.2.5 An Alternate Strategy Based on Instantaneous
Symmetrical Components 355
9.3 DVR STRUCTURE 359
9.3.1 Output Feedback Control of DVR 360
9.3.2 State Feedback Control ofDVR 365
9.4 VOLTAGE RESTORATION 370
9.5 SERIES ACTIVE FILTER 372