1、IEEE Std 1527-2006IEEE Recommended Practice for theDesign of Flexible Buswork Located inSeismically Active AreasI E E E3 Park Avenue New York, NY10016-5997, USA1 September 2006IEEE Power Engineering SocietySponsored by theSubstations CommitteeIEEE Std 1527-2006IEEE Recommended Practice for the Desig
2、n of Flexible Buswork Located in Seismically Active Areas Sponsor Substations Committee of theIEEE Power Engineering SocietyApproved 30 March 2006IEEE-SA Standards BoardThe Institute of Electrical and Electronics Engineers, Inc.3 Park Avenue, New York, NY 10016-5997, USACopyright 2006 by the Institu
3、te of Electrical and Electronics Engineers, Inc.All rights reserved. Published 1 September 2006. Printed in the United States of America.IEEE is a registered trademark in the U.S. Patent +1 978 750 8400. Permission to photocopy portions ofany individual standard for educational classroom use can als
4、o be obtained through the Copyright ClearanceCenter.iv Copyright 2006 IEEE. All rights reserved.IntroductionThis introduction provides some background on the rationale used to develop this recommended practice.This information is meant to aid in the understanding and usage of this recommended practi
5、ce.Flexible buswork consisting mainly of bare aluminum or copper conductors with bolted or welded connectorhardware have been used for many years as part of the electrical buswork system in substations. In general,they are utilized to simplify equipment interconnection with the main bus because they
6、 are easy to installand help ensure that the vertical and horizontal load limits of the equipment terminals are not exceeded.However, recent earthquakes in many parts of the world demonstrated that more attention must be paid tothese flexible buswork designs for facilities in seismically active area
7、s because flexible buswork canincrease the probability that a facility will still be operational after an earthquake. During an earthquake, flexible buswork conductors may transfer significant mechanical forces at theequipment terminals, due to the dynamic effects induced by their motion when adjace
8、nt interconnectedequipment push and pull on these connections. Improperly designed flexible buswork may thus result inexceeding the load limits permitted at the equipment terminals. This can lead to a piece of relativelyinexpensive equipment contributing to the failure of a more expensive one and pe
9、rhaps, starting a cascadeeffect that could result in loss of substantial revenue and expensive equipment.This recommended practice will cover how to design flexible buswork for substation buswork systems orequipment connections to account for seismic movement. It provides a more detailed discussion
10、of thematerial covered in IEEE Std 693to guide the substation designers with this aspect of seismic design. Inshort, this recommended practice covers how to determine the amount of seismically-induced equipmentmotion that may occur, how to determine conductor flexibility, how to specify the amount o
11、f slack required,and what other factors must be considered as part of the design of flexible buswork for new and existinginstallations. It will also report on the current state of knowledge concerning the dynamic effects ofconductors and flexible high-current buswork interconnections.Notice to users
12、ErrataErrata, if any, for this and all other standards can be accessed at the following URL: http:/standards.ieee.org/reading/ieee/updates/errata/index.html. Users are encouraged to check this URL forerrata periodically.InterpretationsCurrent interpretations can be accessed at the following URL: htt
13、p:/standards.ieee.org/reading/ieee/interp/index.html.PatentsAttention is called to the possibility that implementation of this standard may require use of subject mattercovered by patent rights. By publication of this standard, no position is taken with respect to the existence orvalidity of any pat
14、ent rights in connection therewith. The IEEE shall not be responsible for identifyingpatents or patent applications for which a license may be required to implement an IEEE standard or forconducting inquiries into the legal validity or scope of those patents that are brought to its attention.This in
15、troduction is not part of IEEE Std 1527-2006, IEEE Recommended Practice for the Design of FlexibleBuswork Located in Seismically Active Areas.Copyright 2006 IEEE. All rights reserved. vParticipantsAt the time this standard was completed, the working group had the following membership: Jean-Bernard D
16、astous, ChairRobert (Bob) Stewart, Co-ChairJohn Randolph, Vice-ChairRandy Clelland, SecretaryThe following members of the individual balloting committee voted on this standard. Balloters may havevoted for approval, disapproval, or abstention. Stephen AllenRobert (Steve) BrownRulon R. FronkJohn Irvin
17、eLincoln KogaDonald N. LairdKenneth LoJohn NorbergTony OpsetmoenSam PerkinsBill ThompsonCharles F. ToddJim WardinWilliam J. Ackerman Steven C. Alexanderson Ali Al Awazi Saber Azizi-Ghannad Michael P. Baldwin Thomas M. Barnes Michael J. Bio Steven R. Brockschink Steven D. Brown Terry Burley Ted A. Bu
18、rse Randy D. Clelland Tommy P. Cooper Jean-Bernard Dastous Dennis F. Decosta Gary R. Engmann Rulon R. Fronk Eric M. Fujisaki Edgar O. Galyon David L. Gilmer Randall C. Groves Dennis Horwitz Jose A. Jarque Lars E. Juhlin Piotr Karocki Leon Kempner Jr. Kamran Khan Hermann Koch Jim Kulchisky L. W. Kurt
19、z Jr. Donald N. Laird Albert Livshitz Lisardo Lourido William Lumpkins G. L. Luri Keith N. Malmedal Frank W. Mayle Peter J. Meyer Gary L. Michel Jon Mochizuki Jeffrey H. Nelson Michael S. NewmanRobert S. Nowell John D. Randolph Devki N. Sharma Hyeong J. SimGarry M. Simms David Singleton Douglas W. S
20、mith Brian K. Story S. ThamilarasanWilliam R. Thompson James E. TimperleyCharles F. ToddJames W. Wilson Jr. Roland E. Youngbergvi Copyright 2006 IEEE. All rights reserved.When the IEEE-SA Standards Board approved this standard on 30 March 2006, it had the followingmembership:Steve M. Mills, ChairRic
21、hard H. Hulett, Vice ChairDon Wright, Past ChairJudith Gorman, Secretary*Member EmeritusAlso included are the following nonvoting IEEE-SA Standards Board liaisons:Satish K. Aggarwal, NRC RepresentativeRichard DeBlasio, DOE RepresentativeAlan H. Cookson, NIST RepresentativeDon MessinaIEEE Standards P
22、rogram Manager, Document DevelopmentMark D. BowmanDennis B. BrophyWilliam R. GoldbachArnold M. GreenspanRobert M. GrowJoanna N. GueninJulian Forster*Mark S. HalpinKenneth S. HanusWilliam B. HopfJoseph L. Koepfinger*David J. LawDaleep C. MohlaT. W. OlsenGlenn ParsonsRonald C. PetersenTom A. PrevostGr
23、eg RattaRobby RobsonAnne-Marie SahazizianVirginia C. SulzbergerMalcolm V. ThadenRichard L. TownsendWalter WeigelHoward L. WolfmanCopyright 2006 IEEE. All rights reserved. viiContents1. Overview 11.1 Scope 11.2 Purpose. 12. Normative references. 23. Definitions, abbreviations, and acronyms 23.1 Defin
24、itions . 23.2 Abbreviations and acronyms . 44. Equipment movement 44.1 Calculation methods to evaluate standalone equipment displacement 44.2 Testing methods to evaluate standalone equipment displacement 74.3 Site-specific conditions 74.4 Minimum conductor slack and necessary conductor length betwee
25、n equipment interconnected through flexible buswork 85. Other connection possibilities 96. High-current connections. 97. Type of material to usecopper versus aluminum . 118. Conductor mechanical properties 128.1 Recommended values of E and I for calculations 138.2 Confirmation by testing . 148.3 Sin
26、gle- and multi-conductor bundles. 149. Spacers for bundled conductors. 1410. Other considerations 1510.1 Electrical clearances 1510.2 Corona losses . 1610.3 Current-carrying capacity 1710.4 Wind and ice effects 1710.5 Fault conditions 1810.6 Loads on terminal pads and seismically-induced dynamic eff
27、ects of conductors. 1810.7 Three-dimensional (3-D) effects of earthquakes . 1911. Conductor configurations 2011.1 Recommended configurations . 2011.2 Calculation method for verifying electrical clearances . 2211.3 Methods to establish configuration flexibility and terminal loads 2211.4 Connection ha
28、rdware . 27viii Copyright 2006 IEEE. All rights reserved.Annex A (normative) Normative tables. 28Annex B (informative) Tables . 30Annex C (normative) Figures supporting this recommended practice 34Annex D (informative) Informative figures. 44Annex E (informative) Summary of research done on dynamic
29、effects of flexible conductors used in substations. 49Annex F (informative) Bibliography . 53Copyright 2006 IEEE. All rights reserved. 1IEEE Recommended Practice for the Design of Flexible Buswork Located in Seismically Active Areas1. OverviewThe use of suitably designed and installed flexible buswo
30、rk connections must be considered when seismi-cally hardening a substation. Installation of buswork connections to the equipment is a factor that greatlyaffects the seismic performance of the installed equipment. If the buswork is not properly designed, equip-ment that would otherwise survive may fa
31、il, resulting in unnecessary financial losses. The use of seismicallydesigned and installed flexible connections increases the probability that a facility will still be operationalafter an earthquake.This recommended practice will cover the design of flexible buswork connections to account for seism
32、icmovement, as well as other factors that must be considered as part of this design, as per the general decisiontree diagram shown in Figure C.1.This recommended practice also contains five annexes. Annex A and Annex B contain the tables referencedin the main body of the recommended practice, while
33、Annex C and Annex D contain the figures referenced.Annex E provides the latest information on dynamic effects of conductors and a Bibliography is presented inAnnex F.1.1 ScopeThe scope of this document is the engineering and design of flexible bus connections for bus and equipmentin electric power s
34、ubstations.1.2 PurposeThis document was prepared to provide guidance to the substation designer on flexible buswork seismicdesign and to provide information accounting for the current state of knowledge concerning the dynamiceffects of conductors and high-current connections.IEEEStd 1527-2006 IEEE R
35、ECOMMENDED PRACTICE FOR THE DESIGN OF2 Copyright 2006 IEEE. All rights reserved.2. Normative referencesThis recommended practice shall be used in conjunction with the following publications. If the followingpublications are superseded by an approved revision, the revision shall apply:IEEE Std 605-19
36、98, IEEE Guide for Design of Substation Bus Structures.1, 2IEEE Std 693-2005, IEEE Recommended Practice for the Seismic Design of Substations.IEEE Std 738-1993, IEEE Standard for Calculating the Current-Temperature Relationship of Bare Over-head Conductors.3. Definitions, abbreviations, and acronyms
37、For the purposes of this recommended practice, the following terms and definitions apply. The AuthoritativeDictionary of IEEE Standard Terms B33should be referenced for terms not defined in this clause.3.1 Definitions3.1.1 basketing of conductors (also called “bird caging”): The unraveling or untwis
38、ting of outer and innerstrands. Basketing can be caused by the following:a) Minimum bending radius is violatedb) Ends being twisted opposite to direction of twist3.1.2 bundled conductor: An assembly of two or more conductors used as a single conductor and employ-ing spacers to maintain a predetermin
39、ed configuration. The individual conductors of this assembly are calledsubconductors. 3.1.3 complete quadratic combination (CQC method): A modal combination method, especially usefulfor systems with closely spaced frequencies. 3.1.4 conductor configuration: The generic term for a flexible buswork co
40、nnection geometry that has beendesigned to accommodate a certain amount of movement at its end points, without putting undue strain orstress on these end points.3.1.5 critical damping: The least amount of viscous damping that causes a single-degree-of-freedom sys-tem to return to its original positi
41、on without oscillation after initial disturbance.3.1.6 damping: An energy dissipation mechanism that reduces the response amplification and broadens thevibratory response over frequency in the region of resonance. Damping is usually expressed as a percentageof critical damping. See also: critical da
42、mping.3.1.7 drops: The field or construction term for the flexible buswork connections made between a high bus-work section, either rigid or strain, and a piece of equipment or lower buswork section.1IEEE publications are available from the Institute of Electrical and Electronics Engineers, 445 Hoes
43、 Lane, P.O. Box 1331, Piscataway, NJ 08855-1331, USA (http:/standards.ieee.org/).2The IEEE standards or products referred to in this clause are trademarks of the Institute of Electrical and Electronics Engineers, Inc.3The numbers in brackets correspond to those of the bibliography in Annex F.IEEEFLE
44、XIBLE BUSWORK LOCATED IN SEISMICALLY ACTIVE AREAS Std 1527-2006Copyright 2006 IEEE. All rights reserved. 33.1.8 flexible buswork or flexible buswork connections: The terms given to the section of buswork that isusually made up of stranded bare conductors (as opposed to rigid conductors) electrically
45、 interconnectingtwo pieces of equipment, a piece of equipment and a section of rigid bus or two sections of rigid bus.3.1.9 g: Acceleration due to gravity, that is 9.81 m/s2.3.1.10 ground acceleration: The acceleration of the ground resulting from the motion of a given earth-quake. The maximum or pe
46、ak ground acceleration is the zero period acceleration (ZPA) of the groundresponse spectrum. 3.1.11 natural frequency: A frequency at which a body or system vibrates due to its own physical charac-teristics (mass and stiffness) when the body or system is distorted and then released.3.1.12 pinch effe
47、ct: The “pinch effect” is caused by the bending of the conductor during the high velocitymovement caused by the short-circuit forces near where a spacer or equipment terminal clamp is attached.3.1.13 pull-push tests: The name given to the test to determine how flexible a certain conductor configura-
48、tion is when its end points are pulled apart or pushed together. The results of this test are units of force perdisplacement of the conductor from its connection point.3.1.14 response spectrum: A plot of the maximum response of an array of single-degree-of-freedom(SDOF) identically damped oscillator
49、s with different frequencies, all subjected to the same base excitation.See also: single-degree-of-freedom system (SDOF system).3.1.15 seismically decouple: The term to describe how two pieces of equipment or a piece of equipmentand a rigid bus section can be interconnected electrically by a flexible buswork connection, which ideallyallows independent movement, or at least, minimized interaction between the two components.3.1.16 seismicity: Seismic activity; the occurrence of earthquakes in time and space.3.1.17 single-degree-of-freedom system (SDOF system): The i
