IEEE-389-1996.pdf

Recognized as an American National Standard (ANSI) The Institute of Electrical and Electronics Engineers, Inc. 345 East 47th Street, New York, NY 10017-2394, USA Copyright © 1997 by the Institute of Electrical and Electronics Engineers, Inc. All rights reserved. Published 1997. Printed in the United States of America ISBN 1-55937-761-5 No part of this publication may be reproduced in any form, in an electronic retrieval system or otherwise, without the prior written permission of the publisher. IEEE Std 389-1996 (Revision of IEEE Std 389-1990) IEEE Recommended Practice for Testing Electronics Transformers and Inductors Sponsor Electronics Transformer Technical Committee of the IEEE Power Electronics Society Approved 20 June 1996 IEEE Standards Board Approved 6 January 1997 American National Standards Institute Abstract: A number of tests are presented for use in determining the significant parameters and performance characteristics of electronics transformers and inductors. These tests are designed primarily for transformers and inductors used in all types of electronics applications, but they may apply to the other types of transformers of large apparent-power rating used in the electric power utility industry. Keywords: common-mode rejection tests, corona tests, current transformer tests, electronic induc- tors, electronic power transformers, inductance measurements, inrush-current evaluation, insula- tion tests, large rectifiers, noise tests, product rating, pulse transformers, quality factor, resistance tests, self-resonance, temperature rise tests, terminated impedance measurements, transformer capacitance, voltage-time shielding IEEE Standards documents are developed within the IEEE Societies and the Standards Coordinat- ing Committees of the IEEE Standards Board. Members of the committees serve voluntarily and without compensation. They are not necessarily members of the Institute. 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To arrange for payment of licensing fee, please contact Copyright Clearance Center, Customer Service, 222 Rosewood Drive, Danvers, MA 01923 USA; (508) 750-8400. Permission to photocopy portions of any individual standard for educational class- room use can also be obtained through the Copyright Clearance Center. Note: Attention is called to the possibility that implementation of this standard may require use of subject matter covered by patent rights. By publication of this standard, no position is taken with respect to the existence or validity of any patent rights in connection therewith. The IEEE shall not be responsible for identifying patents for which a license may be required by an IEEE standard or for conducting inquiries into the legal validity or scope of those patents that are brought to its attention. iii Introduction (This introduction is not part of IEEE Std 389-1996, IEEE Recommended Practice for Testing Electronics Transformers and Inductors.) This recommended practice has been prepared to serve as a guide in the design, testing, and specifying of electronics transformers and inductors. This document contains many tests and experimental methods for evaluating almost every aspect of electronics transformer performance, including a number of tests for deter- mining transformer environmental characteristics such as audible-noise generation. The tests and specifi ca- tions included are aimed primarily at the testing and evaluation of transformers of relatively low apparent- power rating, such as those used in communications, instrumentation, control, small appliances, and com- puter applications. However, most of these tests are perfectly applicable to transformers of any rating. A use- ful feature of this recommended practice is the listing, in clause 4, of all standard tests used in the specifi cation of a transformer. This clause will provide a useful starting point for many users of this recom- mended practice. MKS units (Standard International or SI units) are used throughout this recommended practice; equivalent CGS units are sometimes given where their usage is still common practice. Defi nitions and symbols are in accordance with those of the International Electrotechnical Commission (IEC) wherever possible. The Electronics Transformer Technical Committee (ETTC) wishes to acknowledge its indebtedness to those who have so freely given of their time and knowledge in the development of the original version of this rec- ommended practice. The fellowship of authors of the inaugural publication, IEEE Std 389-1979, includes the following distinguished members: Paul K. Goethe, Chair This recommended practice was prepared by the Working Group on Transformer Tests of the Test Codes Subcommittee of the Electronics Transformer Technical Committee of the IEEE Power Electronics Society, which was comprised of the following membership: Robert B. Beers, Chair When the Electronics Transformer Technical Committee balloted and approved this recommended practice, the membership was as follows: Rohn R. Grant, Chair J. Adams R. P. Carey M. I. Distefano R. C. Fischer P. C. Hill H. W. Lord H. S. Mitsanas J. Tardy H. I. Tillinger A. A. Toppeto J. S. Andresen I. D. Bolt M. Carey J. Cronk J. DeCramer C. J. Elliott P. K. Goethe W. D. Goethe R. R. Grant H. E. Lee D. N. Ratliff R. L. Sell J. Silgailis B. Thackwray M. A. Wilkowski H. Yarpezeshkan J. S. Andresen R. B. Beers M. Carey J. Cronk J. DeCramer C. J. Elliott P. K. Goethe W. D. Goethe D. N. Ratliff R. L. Sell J. Silgailis B. Thackwray M. A. Wilkowski* H. Yarpezeshkan *Current ETTC Chair iv When the IEEE Standards Board approved this recommended practice on 20 June 1996, it had the following membership: Donald C. Loughry, Chair Richard J. Holleman, Vice Chair Andrew G. Salem, Secretary *Member Emeritus Also included are the following nonvoting IEEE Standards Board liaisons: Satish K. Aggarwal Alan H. Cookson Chester C. Taylor Valerie E. Zelenty IEEE Standards Project Editor Gilles A. Baril Clyde R. Camp Joseph A. Cannatelli Stephen L. Diamond Harold E. Epstein Donald C. Fleckenstein Jay Forster* Donald N. Heirman Ben C. Johnson E. G. “Al” Kiener Joseph L. Koepfi nger* Stephen R. Lambert Lawrence V. McCall L. Bruce McClung Marco W. Migliaro Mary Lou Padgett John W. Pope Jose R. Ramos Arthur K. Reilly Ronald H. Reimer Gary S. Robinson Ingo Rüsch John S. Ryan Chee Kiow Tan Leonard L. Tripp Howard L. Wolfman v Contents CLAUSEPAGE 1.Overview 1 1.1 Scope 1 1.2 Transformers and inductors. 1 2.References 2 3.Definitions 3 4.How to specify electronics transformers 3 5.Insulation and corona tests. 3 5.1 General. 3 5.2 Electric strength test (hi-pot test). 7 5.3 Induced potential test. 8 5.4 Corona tests 10 6.DC resistance tests. 13 6.1 General. 13 6.2 Resistance values under 1 Kelvin double-bridge method. 13 6.3 Resistance values from 1 to many kilohms . 14 6.4 Digital ohmmeterResistance values from under 1 to many kilohms. 17 7.Loss measurements 18 7.1 No-load loss. 18 7.2 Excitation apparent-power measurements. 22 7.3 Stray-load losses 22 7.4 Short-circuit power test 24 7.5 Efficiency and power factor. 25 8.Ratio of transformation 26 8.1 General. 26 8.2 Measurement methods. 28 8.3 Impedance unbalance. 29 8.4 Balance tests. 31 8.5 Polarity tests. 31 9.Transformer capacitance 33 9.1 General. 33 9.2 Interwinding capacitance. 34 9.3 Distributed capacitance 35 9.4 Bridge methods 36 vi CLAUSEPAGE 10.Inductance measurements by impedance bridge method. 36 10.1 General. 36 10.2 Method of measurement 37 11.Transformer response measurements. 41 11.1 Transformer frequency response 41 11.2 Transformer pulse response. 43 12.Noise tests 45 12.1 Test conditions for audible noise. 45 12.2 Measurement of audible noise. 45 13.Terminated impedance measurements. 46 13.1 General. 46 13.2 Return-loss method 46 14.Temperature rise tests 48 14.1 Test methods 48 14.2 Notes on the technique of measurement 49 15.Self-resonance 50 15.1 General. 50 15.2 Measurement 50 16.Voltage-time product rating. 51 16.1 General. 51 16.2 Recommended voltage-time product test methods 52 17.Shielding 53 17.1 Electrostatic shielding 53 17.2 Magnetic shielding. 57 18.Measurement of quality factor Q . 57 18.1 Definition. 57 18.2 Methods 58 18.3 Bridge measurements. 58 18.4 Q -Meter measurements 58 18.5 Transmission method. 59 18.6 Damped oscillation method. 60 19.Common-mode rejection test. 63 vii CLAUSEPAGE 20.Inrush-current evaluation and measurement 64 20.1 Measurement 64 20.2 Calculation. 64 20.3 Other considerations 65 21.Current transformer test. 66 21.1 General. 66 21.2 Recommended test procedure for current-transformation ratio and phase angle 66 22.Bibliography 67 ANNEX Annex A(informative) Instrumentation for voltage and current measurements on inductors and transformers. 69 Annex B(informative) AC High-potential dielectric testing71 Annex C (informative) An ac magnetic field pickup probe73 1 IEEE Recommended Practice for Testing Electronics Transformers and Inductors 1. Overview 1.1 Scope This recommended practice presents a number of tests for use in determining the signifi cant parameters and performance characteristics of electronics transformers and inductors. These tests are designed primarily for transformers and inductors used in all types of electronics applications, but they may apply to the other types of transformers of large apparent-power rating used in the electric power utility industry. Some of the tests described are intended for qualifying a product for a specifi c application, while others are test practices used widely for manufacturing and customer acceptance testing. Clause 4 is intended to serve as a guide for particular application categories. The tests described in this recommended practice include those most commonly used in the electronics transformer industry: electric strength, resistance, power loss, inductance, impedance, balance, ratio of transformation, and many others used less frequently. 1.2 Transformers and inductors The following are the specifi c types of transformers and inductors to which this recommended practice is applicable: a)Electronic power 1)Power 2)Isolating 3)Current limiting 4) Rectifi er 5) Combination (rectifi er and fi lament) 6)Ferroresonant 7)Converter 8)Polyphase 9)Switch mode 10) Magnetic amplifi ers b) Large rectifi ers c)Pulse IEEE Std 389-1996 IEEE RECOMMENDED PRACTICE FOR TESTING 2 1)Voltage stepdown 2)Voltage stepup 3)Low ratio inverting 4)Low power pulse 5)Square-loop d)Broadband 1)Impedance matching 2)DC insulating 3)Common-mode rejection 4)Potential transformers 5)Current transformers 6)Filter inductors 7)Charging inductors 8)Hybrid transformers 2. References This recommended practice shall be used in conjunction with the following publications. When the follow- ing standards are superseded by an approved revision, the revision shall apply. ANSI S1.4-1983, Specifi cation for Sound Level Meters. 1 IEEE Std 4-1995, IEEE Standard Techniques for High-Voltage Testing (ANSI). 2 IEEE Std 100-1996, IEEE Standard Dictionary of Electrical and Electronics Terms. IEEE Std 111-1984, IEEE Standard for Wide-Band Transformers (ANSI). 3 IEEE Std 119-1974, IEEE Recommended Practice for General Principles of Temperature Measurement as Applied to Electrical Apparatus. 4 IEEE Std 260.1-1993, IEEE Standard Letter Symbols for Units of Measurement (SI Units, Customary Inch- Pound Units, and Certain Other Units) (ANSI). IEEE Std 272-1970 (Reaff 1976), IEEE Standard for Computer-Type (Square-Loop) Pulse Transformers. 5 IEEE Std 280-1985, IEEE Standard Letter Symbols for Quantities Used in Electrical Science and Electrical Engineering (ANSI). IEEE Std 295-1969 (Reaff 1993), IEEE Standard for Electronics Power Transformers (ANSI). IEEE Std 315-1975 (Reaff 1993), IEEE Standard Graphic Symbols for Electrical and Electronics Diagrams (ANSI/DoD). 1 ANSI publications are available from the Sales Department, American National Standards Institute, 11 West 42nd Street, 13th Floor, New York, NY 10036, USA. 2 IEEE publications are available from the Institute of Electrical and Electronics Engineers, 445 Hoes Lane, P.O. Box 1331, Piscataway, NJ 08855-1331, USA. 3 IEEE Std 111-1984 has been withdrawn; however, copies can be obtained from Global Engineering, 15 Inverness Way East, Engle- wood, CO 80112-5704, USA, tel. (303) 792-2181. 4 IEEE Std 119-1974 has been withdrawn; however, copies can be obtained from Global Engineering, 15 Inverness Way East, Engle- wood, CO 80112-5704, USA, tel. (303) 792-2181. 5 IEEE Std 272-1970 has been withdra