IEC_TR_61000-2-14-2006.pdf

TECHNICAL REPORT IECTR 61000-2-14 First edition2006-12 Electromagnetic compatibility(EMC)Part 2-14:Environment Overvoltages on public electricity distribution networks Reference number IEC/TR 61000-2-14:2006(E)LICENSED TO MECON Limited.-RANCHI/BANGALOREFOR INTERNAL USE AT THIS LOCATION ONLY,SUPPLIED BY BOOK SUPPLY BUREAU.Publication numbering As from 1 January 1997 all IEC publications are issued with a designation in the 60000 series.For example,IEC 34-1 is now referred to as IEC 60034-1.Consolidated editions The IEC is now publishing consolidated versions of its publications.For example,edition numbers 1.0,1.1 and 1.2 refer,respectively,to the base publication,the base publication incorporating amendment 1 and the base publication incorporating amendments 1 and 2.Further information on IEC publications The technical content of IEC publications is kept under constant review by the IEC,thus ensuring that the content reflects current technology.Information relating to this publication,including its validity,is available in the IEC Catalogue of publications(see below)in addition to new editions,amendments and corrigenda.Information on the subjects under consideration and work in progress undertaken by the technical committee which has prepared this publication,as well as the list of publications issued,is also available from the following:IEC Web Site(www.iec.ch)Catalogue of IEC publications The on-line catalogue on the IEC web site(www.iec.ch/searchpub)enables you to search by a variety of criteria including text searches,technical committees and date of publication.On-line information is also available on recently issued publications,withdrawn and replaced publications,as well as corrigenda.IEC Just Published This summary of recently issued publications(www.iec.ch/online_news/justpub)is also available by email.Please contact the Customer Service Centre(see below)for further information.Customer Service Centre If you have any questions regarding this publication or need further assistance,please contact the Customer Service Centre:Email:custserviec.ch Tel:+41 22 919 02 11 Fax:+41 22 919 03 00 LICENSED TO MECON Limited.-RANCHI/BANGALOREFOR INTERNAL USE AT THIS LOCATION ONLY,SUPPLIED BY BOOK SUPPLY BUREAU.TECHNICAL REPORT IECTR 61000-2-14 First edition2006-12 Electromagnetic compatibility(EMC)Part 2-14:Environment Overvoltages on public electricity distribution networks PRICE CODE IEC 2006 Copyright-all rights reserved No part of this publication may be reproduced or utilized in any form or by any means,electronic or mechanical,including photocopying and microfilm,without permission in writing from the publisher.International Electrotechnical Commission,3,rue de Varemb,PO Box 131,CH-1211 Geneva 20,SwitzerlandTelephone:+41 22 919 02 11 Telefax:+41 22 919 03 00 E-mail:inmailiec.ch Web:www.iec.ch X For price,see current catalogueCommission Electrotechnique InternationaleInternational Electrotechnical Commission LICENSED TO MECON Limited.-RANCHI/BANGALOREFOR INTERNAL USE AT THIS LOCATION ONLY,SUPPLIED BY BOOK SUPPLY BUREAU.2 TR 61000-2-14 IEC:2006(E)CONTENTS FOREWORD.4 INTRODUCTION.6 1 Scope.7 2 Normative references.7 3 Terms and definitions.7 4 Description of overvoltages.10 4.1 General.10 4.2 External overvoltages.11 4.3 Internal overvoltages.11 4.4 Overvoltage waveshape.11 5 Long duration overvoltages.12 5.1 Sustained earth faults.12 5.2 Broken neutral on LV network.12 5.3 Maloperation of voltage regulating equipment.13 5.4 Overvoltages due to voltage unbalances.13 5.5 Dispersed generation.14 6 Short duration overvoltages.15 6.1 Earth faults.15 6.2 Load rejection(sudden load loss).16 6.3 Self-excitation.16 6.4 Resonance and ferroresonance.16 7 Very short duration overvoltages(transients).18 7.1 General description.18 7.2 Lightning.19 7.3 Switching.20 7.4 Summary of surge duration and cause.26 8 Effects of overvoltages on equipment.27 8.1 General considerations.27 8.2 Reduction in life of filament lamps.28 8.3 Effect of overvoltages on IT equipment.28 9 Case studies.29 9.1 General.29 9.2 Switching of LV power factor correction capacitor.29 9.3 Metal fusion furnace.30 9.4 Switching of MV power factor correction capacitor.31 9.5 DC traction system.32 9.6 Load switching.34 10 Protection against the effects of overvoltages.36 10.1 General considerations.36 10.2 Point on wave switching.36 10.3 Arcing horns and spark gaps.37 10.4 Overvoltage protection relays.38 10.5 Snubbers(high frequency RC filter).38 10.6 Uninterruptible power supply(UPS)systems.39 LICENSED TO MECON Limited.-RANCHI/BANGALOREFOR INTERNAL USE AT THIS LOCATION ONLY,SUPPLIED BY BOOK SUPPLY BUREAU.TR 61000-2-14 IEC:2006(E)3 10.7 Surge protection device(SPD).39 11 Conclusions.41 12 Recommendations.42 Bibliography.43 Figure 1 Lightning impulse test voltage characteristic.11 Figure 2 Broken neutral on LV network.13 Figure 3 The effect of distributed generation on network voltage.14 Figure 4 Line Neutral temporary overvoltage on healthy phase for single p