1、Recognized as anAmerican National Standard (ANSI)Copyright 1989 byThe Institute of Electrical and Electronics Engineers, Inc.3 Park Avenue, New York, NY 10016-5997, USANo part of this publication may be reproduced in any form, in an electronic retrieval system or otherwise, without the priorwritten
2、permission of the publisher.IEEE Std C62.92.2-1989 (R2005)IEEE Guide for the Application of Neutral Grounding in Electrical Utility Systems Part II-Grounding of Synchronous Generator SystemsSponsorSurge Protective Devices Committeeof theIEEE Power Engineering SocietyReaffirmed October 30, 2000Approv
3、ed October 13, 1989American National Standards InstituteReaffirmed June 9, 2005Approved February 2, 1989IEEE-SA Standards BoardIEEE Standards documents are developed within the Technical Committees of the IEEE Societies and the StandardsCoordinating Committees of the IEEE Standards Board. Members of
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6、urthermore, the viewpoint expressed at the time a standard is approved and issued is subject to changebrought about through developments in the state of the art and comments received from users of the standard. EveryIEEE Standard is subjected to review at least every five years for revision or reaff
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8、tandard.Comments for revision of IEEE Standards are welcome from any interested party, regardless of membership affiliationwith IEEE. Suggestions for changes in documents should be in the form of a proposed change of text, together withappropriate supporting comments.Interpretations: Occasionally qu
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12、without regard towhether their adoption may involve patents on articles, materials, or processes. Such adoption does not assumeany liability to any patent owner, nor does it assume any obligation whatever to parties adopting the standardsdocuments.iiiForeword(This Foreword is not a part of IEEE C62.
13、92.2-1989, IEEE Guide for the Application of Neutral Grounding in Electrical UtilitySystems, Part IIGrounding of Synchronous Generator Systems.)This guide is the second in a series of documents on neutral grounding in electric utility systems. Part II covers theconsiderations and practices relating
14、to the grounding of synchronous generator systems.Emphasis in this guide is to be directed toward the grounding of synchronous generator systems in electric utilitysystems. Generator grounding practices used in industrial systems are covered in other guides and standards.At the time this guide was a
15、pproved, the Working Group for Part II had the following membership:S. G. Whisenant, Chair S. MazumdarW. S. OssmanG. S. HaralampuD. W. JacksonI. B. JohnsonJ. L. KoepfingerE. R. Taylor, Jr.O. Nigol J. R. DetweilerThe following persons were on the balloting committee that approved this document for su
16、bmission to the IEEEStandards Board:R. D. BallC. L. BallentineG. D. BreuerJ. J. BurkeJ. G. DaltonD. C. DawsonR. W. FlugumH. E. FoelkerG. L. GaibroisE. A. GoodmanR. HaasC. D. HansellG. S. HaralampuD. E. HedmanJ. A. HetrickA. R. HilemanW. W. HinesD. W. JacksonR. A. JonesS. S. KershawJ. L. KoepfingerS.
17、 KuznetsovG. E. LeeF. Lembo, Jr.D. W. LenkW. A. MaguireJ. A. MambueaE. H. Marrow, Jr.F. D. MartzloffD. J. MelvoldJ. J. NapiorkowskiO. NigolR. OdenbergJ. C. OsterhoutM. ParenteS. A. PotocnyR. RichmanE. RothongK. B. StumpL. D. SweeneyA. SweetanaD. P. SymanskiE. R. Taylor, Jr.A. C. WestromS. G. Whisena
18、ntE. J. YasudaWhen the IEEE Standards Board approved this standard on February 2, 1989, it had the following membership:Dennis Bodson, Chair Marco W. Migliaro, Vice Chair Andrew G. Salem, Secretary Arthur A. BlaisdellFletcher J. BuckleyAllen L. ClappJames M. DalyStephen R. DillonDonald C. Fleckenste
19、inEugene P. FogartyJay Forster*Thomas L. HannanKenneth D. HendrixTheodore W. Hissey, Jr.John W. HorchDavid W. HutchinsFrank D. KirschnerFrank C. KitzantidesJoseph L. Koepfinger*Edward LohseJohn E. May, Jr.Lawrence V. McCallL. Brace McClungDonald T. Michael*Richard E. MosherStig NilssonL. John Rankin
20、eGary S. RobinsonDonald W. Zipse*Member EmeritusivCLAUSE PAGE1. Scope and References .11.1 Scope 11.2 References 12. Objectives of Generator Grounding32.1 Minimizing Damage for Internal Ground Faults . 32.2 Limiting Mechanical Stress in the Generator for External Ground Faults 42.3 Limiting Overvolt
21、ages on Generator Insulation 42.4 Providing a Means of Generator System Ground-Fault Protection . 82.5 Coordinating with the Other Apparatus at Generator Voltage Level 83. Generator Grounding Types93.1 Unit-Connected Generation Systems . 93.2 Common Bus Generators without Feeders 133.3 Generators wi
22、th Feeders Directly Connected at Generated Voltage . 153.4 Three-Phase, 4-Wire Connected Generators 164. Bibliography16Annex A (Informative) Example of High-Resistance Grounding 18Annex B (Informative) Resonant Grounding of a Unit-Connected Generator System 221IEEE Guide for the Application of Neutr
23、al Grounding in Electrical Utility Systems Part IIGrounding of Synchronous Generator Systems1. Scope and References1.1 ScopeThis section summarizes the general considerations in grounding synchronous generator systems and discusses thefactors to be considered in the selection of a grounding class an
24、d the application of grounding methods. The guidelinesapply to both the large and small generators found in electric utility systems.It should be borne in mind by the user that this report is intended solely as a guide. Statements are necessarily of ageneral nature and, therefore, do not take into a
25、ccount the requirements of special situations that can differconsiderably from those discussed.1.2 ReferencesThe following publications should be used in conjunction with this guide:1 ANSI C50.10-1977, General Requirements for Synchronous Machines.12 ANSI C50.12-1981, Requirements for Salient Pole S
26、ynchronous Generators and Generator/Motors for HydraulicTurbine Applications. 3 ANSI C50.13-1977, Requirements for Cylindrical Rotor Synchronous Generators. 4 ANSI/IEEE C37.101-1985, Guide for Generator Ground Protection.21ANSI publications are available from the Sales Department, American National
27、Standards Institute, 1430 Broadway, New York, NY 10018.2ANSI/IEEE publications are available from the Institute of Electrical and Electronics Engineers, Service Center, 445 Hoes Lane, Piscataway, NJ08855-1331, or from the Sales Department, American National Standards Institute, 1430 Broadway, New Yo
28、rk, NY 10018.2 Copyright 1989 IEEE All Rights ReservedIEEE C62.92.2-1989 IEEE GUIDE FOR THE APPLICATION OF5 ANSI/IEEE C62.2-1987, Guide for Application of Gapped Silicon-Carbide Surge Arresters for AlternatingCurrent Systems. 6 ANSI/IEEE C62.92-1987, Guide for the Application of Neutral Grounding in
29、 Electrical Utility Systems, Part IIntroduction. 7 ANSI/IEEE Std 95-1977 (R1982), Recommended Practice for Insulation Testing of Large AC Rotating Machinerywith High Direct Voltage. 8 ANSI/IEEE Std 433-1974 (R1985), Recommended Practice for Insulation Testing of Large AC RotatingMachinery with High
30、Voltage at Very Low Frequency. 9 ANSI/IEEE Std 519-1981, Guide for the Harmonic Control and Reactive Compensation of Static PowerConverters. 10 ANSI/NFPA 70-1987, National Electrical Code.311 AIEE COMMITTEE REPORT. Relay Protection of AC Generators. AIEE Transactions on Power Apparatusand Systems, v
31、ol PAS-70, 1951, pp 275282.12 ALLEN, J. E. and WALDORF, S. K. Arcing Ground Tests on a Normally Ungrounded 13kV 3-Phase Bus, AIEETransactions on Power Apparatus and Systems, vol 65, 1946, pp 298306.13 BERDY, J., CRENSHAW, M. L., and TEMOSHOK, M. “Protection of Large Steam Turbine-Generators DuringAb
32、normal Operating Conditions,” General Electric Company, GER-2811, 1972.14 BROWN, P. G. “Generator Neutral Grounding,” General Electric Company, GET 1941, 1953, pp 1217.15 BROWN, P. G., JOHNSON, I. B, and STEVENSON, J. R. Generator Neutral Grounding, Some Aspects ofApplication for Distribution Transf
33、ormer with Secondary Resistor and Resonant Types, IEEE Transactions on PowerApparatus and Systems, vol PAS-97, no 3, May/June 1979, pp 683694.16 DANN, W. M. and MONTSINGER, V. M. Overloading of Power Transformers, AIEE Transactions on PowerApparatus and Systems, Oct 1934, p 1353.17 EATON, J. R., PEC
34、K, J. K., and DUNHAM, J. M. Experimental Studies of Arcing Faults on a 75kV TransmissionSystem, AIEE Transactions on Power Apparatus and Systems, vol 50, 1931, pp 14671479.18 GRIFFEN, C. H. and POPE, J. W. Generator Ground Fault Protection Using Overcurrent, Overvoltage, andUndervoltage Relays, IEEE
35、 Transactions on Power Apparatus and Systems, vol PAS-101, no 12, Dec 1982, p 4491.19 GROSS, E. T. B. “Sensitive Generator Ground Fault Protection,” Proceedings of the American Power Conference,vol 36, 1974, p 1034.20 GROSS, E. T. B. and GULACHENSKI, E. M. Experience of the New England Electric Syst
36、em with GeneratorProtection by Resonant Neutral Grounding, IEEE Transactions on Power Apparatus and Systems, vol PAS-92, July/Aug 1973, pp 11861194.21 GULACHENSKI, E. M. and COURVILLE, E. W. New Englands 30 Years of Experience with Resonant NeutralGrounding of Unit-Connected Generators, IEEE Transac
37、tions on Power Apparatus and Systems, Sep 1984, pp 25722578.3NFPA documents are published by the National Fire Protection Association, Publications Sales Division, Batterymarch Park, Quincy, MA 02269.Copies are also available from the Sales Department of the American National Standards Institute, 14
38、30 Broadway, New York, NY 10018.Copyright 1989 IEEE All Rights Reserved 3NEUTRAL GROUNDING IN ELECTRICAL UTILITY SYSTEMS IEEE C62.92.2-198922 IEEE COMMITTEE REPORT. Potential Transformer Application on Unit-Connected Generators, IEEETransactions on Power Apparatus and Systems, 1972, pp 2428.423 KHUN
39、KHUN, K. J. S., KOEPFINGER, J. L., and HADDED, M. V. Resonant Grounding (Ground FaultNeutralizer) of a Unit Connected Generator. IEEE Transactions on Power Apparatus and Systems, vol PAS-96, no 2,Mar/Apr 1977, pp 550559.24 PETERSON, H. A. Transients in Power Systems, Dover Publication, New York, 195
40、1.25 RAJK, M. N. Ground-Fault Protection of Unit-Connected Generators. AIEE Transactions on Power Apparatusand Systems, vol PAS-77, part III, 1958, pp 10821094.26 TEICHMAN, H. T. Improved Maintenance Approach for Large Generator Armature Windings Subject toInsulation Migration. IEEE Transactions on
41、Power Apparatus and Systems, vol PAS-92, 1973, pp 12341238.2. Objectives of Generator GroundingThe principle objective of grounding a synchronous generator system is the protection of the generator and associatedequipment against damage caused by abnormal electrical conditions. The specific objectiv
42、es in the protection of thegenerator are as follows:1) Minimizing damage for internal ground faults.2) Limiting mechanical stress in the generator for external ground faults.3) Limiting TOVs (temporary overvoltages) and transient overvoltages on the generator insulation.4) Providing a means of gener
43、ator system ground fault detection.5) Coordinating the protection of the generator with the requirements of other equipment connected at generatorvoltage level.The choice of grounding class is largely determined by the relative importance to the user of each of the aboveobjectives. The degree to whi
44、ch each of the possible grounding methods accomplishes the desired objectives isdiscussed in the following paragraphs.2.1 Minimizing Damage for Internal Ground FaultsIt has been concluded from field investigations of generator failures that limiting ground current magnitudes/durationsduring internal
45、 line-to-ground faults is no guarantee that core damage will be completely eliminated 11, 26.5However, there is an indication that low-fault currents and fast-fault clearing will minimize core damage since ironburning and damage depend mainly on core current magnitude and duration. The energy genera
46、ted in a fault is equalto I2Rft, where Rfis the fault resistance. This relationship indicates that a reduction in current will have a greaterreduction in fault-heating damage than a proportional reduction in time. However, the energy generated by an arcingfault will not be reduced by the square of t
47、he reduced current as implied by the equation. It will reduce more slowlybecause the arcing fault resistance is neither constant nor linear 25.The available classes of grounding may be ranked as follows in approximate order of increasing fault current:1) Resonant grounded2) Ungrounded3) High-resista
48、nce grounded4IEEE publications are available from IEEE Service Center, 445 Hoes Lane, Piscataway, NY 08855-1331.5The numbers in brackets correspond to those of the references listed in 1.2.4 Copyright 1989 IEEE All Rights ReservedIEEE C62.92.2-1989 IEEE GUIDE FOR THE APPLICATION OF4) Low-resistance
49、grounded5) Low-inductance grounded6) Effectively groundedIt should be noted that the ground-fault current depends not only on the generator grounding, but also on other sourcesof ground current available to the generator. The last three classes have substantially higher fault current levels thanungrounded, resonant grounded, and high-resistance grounded classes (see ANSI/IEEE C62.92-1987, Table 1 6 formore information).In addition to the normal shutdown sequence (eg, tripping the generator breaker and exci
