Electrical distribution engineering PDF
Preview Electrical distribution engineering
Electrical Distribution Engineering 3rd Edition This page intentionally left blank Electrical Distribution Engineering 3rd Edition by Anthony J. Pansini, E.E., P.E. Life Fellow IEEE—Sr. Member ASTM Library of Congress Cataloging-in-Publication Data Pansini, Anthony J. Electrical distribution engineering / by Anthony J. Pansini. -- 3rd ed. p. cm. Includes index. ISBN 0-88173-546-9 (print) -- ISBN 0-88173-547-7 (electronic) 1. Electric power distribution. I. Title. TH3001.P28 2006 621.319--dc22 2006049929 Electrical distribution engineering / by Anthony J. Pansini ©2007 by The Fairmont Press, Inc. All rights reserved. No part of this publica- tion may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopy, recording, or any information storage and retrieval system, without permission in writing from the publisher. Published by The Fairmont Press, Inc. 700 Indian Trail Lilburn, GA 30047 tel: 770-925-9388; fax: 770-381-9865 http://www.fairmontpress.com Distributed by Taylor & Francis Ltd. 6000 Broken Sound Parkway NW, Suite 300 Boca Raton, FL 33487, USA E-mail: [email protected] Distributed by Taylor & Francis Ltd. 23-25 Blades Court Deodar Road London SW15 2NU, UK E-mail: [email protected] Printed in the United States of America 10 9 8 7 6 5 4 3 2 1 0-88173-546-9 (The Fairmont Press, Inc.) 0-8493-8249-1 (Taylor & Francis Ltd.) While every effort is made to provide dependable information, the publisher, authors, and editors cannot be held responsible for any errors or omissions. iv Contents Preface ................................................................................................................xi History and Development ...........................................................................xiii PART ONE THE DISTRIBUTION SYSTEM .........................................1 1 The Distribution System: Description ........................................3 2 Distribution System Considerations ...........................................9 Desired Features ..................................................................................9 Types of Electric Systems ..................................................................10 Types of Delivery Systems ................................................................21 Overhead versus Underground .........................................................32 PART TWO PLANNING AND DESIGN ............................................35 3 Load Characteristics ......................................................................37 Connected Loads ................................................................................37 Consumer Factors ..............................................................................43 Consumer Classification ....................................................................46 Fluctuation in Demand .....................................................................47 Future Requirements .........................................................................48 Voltage Requirements ........................................................................49 Service Reliability ..............................................................................50 4 Electrical Design ............................................................................53 Services ...............................................................................................53 The Secondary System .......................................................................54 The Primary System ..........................................................................63 Voltage Regulators .............................................................................73 Taps ....................................................................................................76 Boosters ..............................................................................................76 Capacitors ...........................................................................................77 Reactors ..............................................................................................80 Transformers ......................................................................................81 Substations .........................................................................................94 Protective Devices ............................................................................100 Fault-Current Calculation ...............................................................119 v Street Lighting .................................................................................129 Practical Basis of Design .................................................................133 5 Mechanical Design: Overhead ..................................................145 Criteria .............................................................................................145 Poles .................................................................................................146 Cross Arms ......................................................................................157 Pins ..................................................................................................163 Secondary Racks ..............................................................................166 Insulators .........................................................................................167 Guys and Anchors ...........................................................................170 Conductors .......................................................................................178 Grades of Construction ...................................................................184 Clearances ........................................................................................185 Joint Construction ...........................................................................188 Practical Design Methods ...............................................................190 Appendix 5 A Practical Method of Calculating Pole and Guy Sizes ............................................203 Introduction ...........................................................203 Pole Class Requirements .......................................204 Guying Requirements ...........................................213 Appendix 5B Examples ..............................................................221 Appendix 5C Concrete and Metal Poles .................................224 Introduction ...........................................................224 Construction ..........................................................225 Installation .............................................................226 Design ....................................................................226 6 Mechanical Design: Underground ...........................................229 High-Density Loads: City and Downtown Areas ..........................229 Practical Manhole Design Procedure .............................................242 Design Loading ................................................................................242 Design Stress Bases .........................................................................245 Wall Design .....................................................................................246 Roof Design ......................................................................................250 Floor Design ....................................................................................252 Reinforcing Specifications ...............................................................253 Gratings ...........................................................................................253 Construction Practices ....................................................................254 vi Reinforced Concrete Design ............................................................255 Sample Design Problem ..................................................................259 Underground Residential Distribution (URD) ..............................268 Design of Direct-buried Electrical Distribution Systems ..............275 Appendix 6A Technical Reference Data ..................................285 Use of Load-Estimating Curves for Residential Loads Including Space Heating .........285 Use of the URD-Loop Primary Conductor Size-Selector Chart .............................288 7 Distribution Substations ............................................................291 Site Selection ....................................................................................291 General Design Features .................................................................292 Substation Construction ..................................................................297 One-Line Diagrams of Connections ...............................................299 8 Metering .........................................................................................301 Scope .................................................................................................301 Operation-Monitoring Meters ........................................................301 Revenue Metering ...........................................................................303 Wiring Diagrams .............................................................................307 Electronic Metering .........................................................................307 Transducers ......................................................................................309 PART THREE MATERIALS AND EQUIPMENT .............................311 9 Conductors .....................................................................................313 Introduction .....................................................................................313 Materials ..........................................................................................313 Cables ...............................................................................................321 Secondary Mains .............................................................................322 Service Conductors ..........................................................................323 Connections ......................................................................................323 Overhead-to-underground Connection ...........................................326 Ties ...................................................................................................326 Electrical Characteristics .................................................................328 10 Poles, Cross Arms, Pins, Racks, and Insulators ....................331 Wood Poles .......................................................................................331 Concrete and Metal Poles ................................................................337 vii Concrete Poles ..................................................................................337 Metal Poles ......................................................................................338 Cross Arms ......................................................................................339 Pins ..................................................................................................340 Racks ................................................................................................342 Insulators .........................................................................................343 Test Voltages ....................................................................................358 Appendix 10A Concrete Distribution Poles: Representative Specifications ......................359 Scope .................................................................359 Shape .................................................................359 Dimensions and Strength ................................360 Colors and Finishes ..........................................360 Materials ...........................................................363 General Requirements ......................................364 Manufacture .....................................................369 11 Transformers, Cutouts, and Surge Arresters ..........................373 Transformers ....................................................................................373 Distribution Transformers ...............................................................375 Fuse Cutouts ....................................................................................382 Surge Arresters ................................................................................386 12 Regulators, Capacitors, Switches, and Reclosers ..................389 Voltage Regulators ...........................................................................389 Capacitors .........................................................................................392 Switches ...........................................................................................395 Circuit Breakers ...............................................................................396 Reclosers ...........................................................................................398 13 Distribution Substation Equipment ........................................399 Equipment ........................................................................................399 Transformers ....................................................................................399 Circuit Breakers and Protective Relaying .......................................403 Fuses .................................................................................................404 Disconnect and Air-Break Switches ...............................................405 Surge or Lightning Arresters ..........................................................406 Voltage Regulators ...........................................................................407 Storage Batteries ..............................................................................408 viii Measuring Instruments ...................................................................408 Capacitors and Street Lighting Equipment ....................................409 Buses and Bus Supports ..................................................................410 All Substation Equipment ...............................................................410 PART FOUR U.S. ENERGY POLICY ACT OF 2005 .........................411 14 U.S. Energy Policy Act of 2005 .................................................413 Preface ..............................................................................................413 Wind Power .....................................................................................413 Solar Power ......................................................................................416 Other “Green” Fuels .......................................................................418 Conservation ....................................................................................419 Storage .............................................................................................419 The Primary Circuit ........................................................................419 PART FIVE OTHER DESIGN CONSIDERATIONS ......................421 15 Nontechnical Considerations ....................................................423 Introduction .....................................................................................423 Safety ................................................................................................423 Quality of Service ............................................................................426 Economy ...........................................................................................427 Conclusion .......................................................................................429 16 Operating Considerations ..........................................................431 Introduction .....................................................................................431 Quality of Service ............................................................................431 Load Shedding ..................................................................................432 Cogeneration and Distributed Generation .....................................435 Metering ...........................................................................................439 Remote Meter Reading and Demand Control ................................441 Transformer Load Monitoring .........................................................441 Power Factor Correction .................................................................442 Demand Control ..............................................................................442 Demand Control (or Peak Suppression) .........................................443 Conclusion .......................................................................................449 APPENDIXES ................................................................................................451 Appendix A Circuit Analysis Methods .................................................453 Introduction ............................................................................................453 ix
The list of books you might like
