1、 Power transformers Part 5:Ability to withstand short circuit Reference number IEC 60076-5:2000(E)INTERNATIONAL STANDARD IEC60076-5 Second edition2000-07 This English-language version is derived from the original bilingual publication by leaving out all French-language pages.Missing page numbers cor
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8、 Tel:+41 22 919 02 11 Fax:+41 22 919 03 00 Power transformers Part 5:Ability to withstand short circuit For price,see current catalogue IEC 2000 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 phot
9、ocopying 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 INTERNATIONAL STANDARD IEC60076-5 Second ed
10、ition2000-07 S Commission Electrotechnique InternationaleInternational Electrotechnical Commission PRICE CODE 60076-5 IEC:2000 3 CONTENTSPageFOREWORD.5Clause1Scope.92Normative references.93Requirements with regard to ability to withstand short circuit.93.1General.93.2Overcurrent conditions.114Demons
11、tration of ability to withstand short circuit.174.1Thermal ability to withstand short circuit.174.2Ability to withstand the dynamic effects of short circuit.23Annex A(informative)Guidance for the identification of a similar transformer.41Annex B(normative)Calculation method for the demonstration of
12、the abilityto withstand the dynamic effects of short circuit.43Figure 1 Star/delta connected transformer.29Figure 2 Star/star auto-transformer.31Table 1 Recognized minimum values of short-circuit impedance for transformerswith two separate windings.13Table 2 Short-circuit apparent power of the syste
13、m.13Table 3 Maximum permissible values of the average temperature of each windingafter short circuit.21Table 4 Values for factor k 2.2560076-5 IEC:2000 5 INTERNATIONAL ELECTROTECHNICAL COMMISSION_POWER TRANSFORMERS Part 5:Ability to withstand short circuitFOREWORD1)The IEC(International Electrotechn
14、ical Commission)is a worldwide organization for standardization comprisingall national electrotechnical committees(IEC National Committees).The object of the IEC is to promoteinternational co-operation on all questions concerning standardization in the electrical and electronic fields.Tothis end and
15、 in addition to other activities,the IEC publishes International Standards.Their preparation isentrusted to technical committees;any IEC National Committee interested in the subject dealt with mayparticipate in this preparatory work.International,governmental and non-governmental organizations liais
16、ingwith the IEC also participate in this preparation.The IEC collaborates closely with the InternationalOrganization for Standardization(ISO)in accordance with conditions determined by agreement between thetwo organizations.2)The formal decisions or agreements of the IEC on technical matters express,as nearly as possible,aninternational consensus of opinion on the relevant subjects since each technical committee has representationfrom all interested National Committees.3)The documents produced h
