Transmission and Distribution Electrical Engineering

1039 Pages·2007·17.33 MB·English

by  Colin Bayliss

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Transmission and Distribution
Electrical Engineering
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Transmission and
Distribution
Electrical
Engineering
Third edition
Dr C. R. Bayliss CEng FIET and
B. J. Hardy ACGI CEng FIET
AMSTERDAM (cid:127) BOSTON (cid:127) HEIDELBERG (cid:127) LONDON (cid:127) NEW YORK (cid:127) OXFORD
PARIS (cid:127) SAN DIEGO (cid:127) SAN FRANCISCO (cid:127) SINGAPORE (cid:127) SYDNEY (cid:127) TOKYO
Newnes is an imprint of Elsevier
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Newnes is an imprint of Elsevier
Linacre House, Jordan Hill, Oxford OX2 8DP
30 Corporate Drive, Suite 400, Burlington, MA 01803, USA
First edition 1996
Second edition 1999
Third edition 2007
Copyright © 1996, 1999 Colin Bayliss. All rights reserved.
Copyright © 2007, Colin Bayliss and Brian Hardy. Published by Elsevier Ltd.
All rights reserved
The right of Colin Bayliss and Brian Hardy to be identified as the authors of this work
has been asserted in accordance with the Copyright, Designs and Patents Act 1988
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 ((cid:1)44) (0) 1865 843830; fax ((cid:1)44) (0) 1865 853333;
email: [email protected]. Alternatively you can submit your request online by
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No responsibility is assumed by the publisher for any injury and/or damage to persons
or property as a matter of products liability, negligence or otherwise, or from any use
or operation of any methods, products, instructions or ideas contained in the material
herein. Because of rapid advances in the medical sciences, in particular, independent
verification of diagnoses and drug dosages should be made
British Library Cataloguing in Publication Data
Bayliss, C. R. (Colin R.)
Transmission and distribution electrical engineering. – 3rd ed.
1. Electric power transmission 2. Electric power distribution
I. Title II. Hardy, B. J.
621.3(cid:2)19
ISBN-13: 978-0-7506-6673-2
ISBN-10: 0-7506-6673-0
For information on all Newnes publications
visit our web site at http://books.elsevier.com
Typeset by Charon Tec Ltd (A Macmillan Company), Chennai, India
www.charontec.com
Printed and bound in Great Britain
06 07 08 09 10 10 9 8 7 6 5 4 3 2 1
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Contents
About the authors xxi
Contributors xxiii
Preface xxvii
1 System Studies 1
1.1 Introduction 1
1.2 Load flow 1
1.2.1 Purpose 1
1.2.2 Sample study 2
1.3 System stability 8
1.3.1 Introduction 8
1.3.2 Analytical aspects 10
1.3.3 Steady state stability 14
1.3.4 Transient stability 17
1.3.5 Dynamic stability 28
1.3.6 Effect of induction motors 29
1.3.7 Data requirements and interpretation of transient 30
stability studies
1.3.8 Case studies 35
1.4 Short circuit analysis
1.4.1 Purpose 42
1.4.2 Sample study 42
2 Drawings and Diagrams 50
2.1 Introduction 50
2.2 Block diagrams 50
2.3 Schematic diagrams 51
2.3.1 Method of representation 51
2.3.2 Main circuits 55
2.3.3 Control, signalling and monitoring circuits 55
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vi Contents
2.4 Manufacturers’drawings 55
2.4.1 Combined wiring/cabling diagrams 55
2.4.2 British practice 61
2.4.3 European practice 64
2.4.4 Other systems 67
2.5 Computer aided design (CAD) 68
2.6 Case study 69
2.7 Graphical symbols 69
Appendix A: Relay identification – numerical codes 71
Appendix B: Comparison between German, British, 82
US/Canadian and international symbols
B1 General circuit elements 83
B2 Operating mechanisms 86
B3 Switchgear 89
3 Substation Layouts 92
3.1 Introduction 92
3.2 Substation design considerations 92
3.2.1 Security of supply 92
3.2.2 Extendibility 93
3.2.3 Maintainability 93
3.2.4 Operational flexibility 94
3.2.5 Protection arrangements 94
3.2.6 Short circuit limitations 94
3.2.7 Land area 94
3.2.8 Cost 95
3.3 Alternative layouts 95
3.3.1 Single busbar 95
3.3.2 Transformer feeder 97
3.3.3 Mesh 101
3.3.4 Ring 103
3.3.5 Double busbar 104
3.3.6 11⁄ Circuit breaker 105
2
3.4 Space requirements 107
3.4.1 Introduction 107
3.4.2 Safety clearances 108
3.4.3 Phase–phase and phase–earth clearances 109
4 Substation Auxiliary Power Supplies 115
4.1 Introduction 115
4.2 DC supplies 115
4.2.1 Battery and charger configurations 115
4.2.2 Battery charger components 118
4.2.3 Installation requirements 121
4.2.4 Typical enquiry data – DC switchboard 125
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Contents vii
4.3 Batteries 126
4.3.1 Introduction 126
4.3.2 Battery capacity 126
4.3.3 Characteristics of batteries 127
4.3.4 Battery sizing calculations 130
4.3.5 Typical enquiry data 133
4.4 AC supplies 135
4.4.1 Power sources 135
4.4.2 LVAC switchboard fault level 137
4.4.3 Auxiliary transformer LV connections 137
4.4.4 Allowance for future extension 139
4.4.5 Typical enquiry data 139
4.4.6 Earthing transformer selection 140
4.4.7 Uninterruptible power supplies 144
5 Current and Voltage Transformers 149
5.1 Introduction 149
5.2 Current transformers 149
5.2.1 Introduction 149
5.2.2 Protection CT classifications 149
5.2.3 Metering CTs 153
5.2.4 Design and construction considerations 154
5.2.5 Terminal markings 156
5.2.6 Specifications 157
5.3 Voltage transformers 157
5.3.1 Introduction 157
5.3.2 Electromagnetic VTs 157
5.3.3 Capacitor VTs 158
5.3.4 Specifications 159
5.4 Future trends 159
6 Insulators 163
6.1 Introduction 163
6.2 Insulator materials 163
6.2.1 Polymeric and resin materials 163
6.2.2 Glass and porcelain 164
6.3 Insulator types 164
6.3.1 Post insulators 164
6.3.2 Cap and pin insulators 168
6.3.3 Long rod 168
6.4 Pollution control 169
6.4.1 Environment/creepage distances 169
6.4.2 Remedial measures 172
6.4.3 Calculation of specific creepage path 173
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6.5 Insulator specification 174
6.5.1 Standards 174
6.5.2 Design characteristics 174
6.6 Tests 180
6.6.1 Sample and routine tests 180
6.6.2 Technical particulars 180
7 Substation Building Services 181
7.1 Introduction 181
7.2 Lighting 181
7.2.1 Terminology 181
7.2.2 Internal lighting 186
7.2.3 External lighting 187
7.2.4 Control 197
7.3 Distribution characterization 199
7.4 Heating, ventilation and air-conditioning 200
7.4.1 Air circulation 200
7.4.2 Air-conditioning 202
7.4.3 Heating 207
7.5 Fire detection and suppression 207
7.5.1 Introduction 207
7.5.2 Fire extinguishers 208
7.5.3 Access, first aid and safety 208
7.5.4 Fire detection 209
7.5.5 Fire suppression 212
7.5.6 Cables, control panels and power supplies 213
8 Earthing and Bonding 215
8.1 Introduction 215
8.2 Design criteria 215
8.2.1 Touch and step voltages 215
8.2.2 Touch and step voltage limits 216
8.3 Substation earthing calculations 219
8.3.1 Environmental conditions 219
8.3.2 Earthing materials 222
8.3.3 Earth resistance and earth potential rise 225
8.3.4 Hazard voltage tolerable limits 227
8.4 Computer simulation 229
References 232
9 Insulation Co-ordination 233
9.1 Introduction 233
9.2 System voltages 233
9.2.1 Power frequency voltage 233
9.2.2 Overvoltages 234
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Contents ix
9.3 Clearances 245
9.3.1 Air 245
9.3.2 SF 248
6
9.4 Procedures for co-ordination 248
9.4.1 The IEC standard approach 248
9.4.2 Statistical approach 249
9.4.3 Non-statistical approach 251
9.5 Surge protection 251
9.5.1 Rod or spark gaps 251
9.5.2 Surge arresters 253
References 268
10 Relay Protection 269
10.1 Introduction 269
10.2 System configurations 270
10.2.1 Faults 270
10.2.2 Unearthed systems 270
10.2.3 Impedance earthed systems 270
10.2.4 Solidly earthed systems 271
10.2.5 Network arrangements 271
10.3 Power system protection principles 274
10.3.1 Discrimination by time 274
10.3.2 Discrimination by current magnitude 275
10.3.3 Discrimination by time and fault direction 275
10.3.4 Unit protection 275
10.3.5 Signalling channel assistance 276
10.4 Current relays 277
10.4.1 Introduction 277
10.4.2 Inverse definite minimum time lag
(IDMTL) relays 277
10.4.3 Alternative characteristic curves 280
10.4.4 Plotting relay curves on log/log graph paper 280
10.4.5 Current relay application examples 281
10.5 Differential protection schemes 292
10.5.1 Biased differential protection 292
10.5.2 High impedance protection 295
10.5.3 Transformer protection application examples 296
10.5.4 Pilot wire unit protection 300
10.5.5 Busbar protection 303
10.6 Distance relays 306
10.6.1 Introduction 306
10.6.2 Basic principles 307
10.6.3 Relay characteristics 307
10.6.4 Zones of protection 313
10.6.5 Switched relays 314