CHHOS/AR3257.99E(D)PrintedinSwitzerland(99-09-1000D/E)ABBHighVoltageTechnologiesLtd.DivisionSurgeArrestersJurastrasse45CH-5430Wettingen1SwitzerlandPleasevisitusontheInternet::ENISO9001TelephoneTelefaxInternet++4156/2052911++4156/2055570salessachhos.mail.abb.com@APPLICATIONGUIDELINESAPPLICATIONGUIDELINESOVERVOLTAGEPROTECTIONDimensioning,testingandapplicationofmetaloxidesurgearrestersinmediumvoltagenetworks1Thefirsteditionofourdirectionsfordimensioning,testingandapplicationofmetaloxidesurgearrestersinmediumvoltagenetworks,whichappearedin1994,wasreceivedverypositively.Wewerepleasedtogetsuchareception,whichattestedourbeliefthatcom-petentconsultingwithregardtotheapplicationofourproductsisasimportantasthequalityoftheproductsitself.Thetechnologicalprogressmadeitnownecessarytoreviseandrenewthepresentbookletforthethirdedition.Thedimensioningandthetheoreticalbasisfortheoptimalapplicationofthesurgearrestersarenotchangedandthereforetheyweretakenassuchinthenewedition.Mr.RenéRudolph,whowasatthetimeofthefirsteditionresponsiblefortheconsultingconcerningapplicationinthesurgearresterdivision,tookonthetaskofrevisingthetables.Thatwasnecessarybecauseoftheimprovementofthetechnicaldataofthesurgearrestersandtheenlargementofourproductrange.WewouldliketothankMr.RenéRudolphforhisefforts.Mr.BernhardRichter,whoisnowresponsibleforengineeringandapplicationoftheovervoltageprotectivedevicesinthesurgearresterdivisionofABBHighVoltageTechnologiesLtd,tookongladlythetaskofthegeneralrevisionofthisbooklet.Mr.RichterisamemberindifferentworkinggroupsofIECSC37AandIECTC81,andhisactivityfieldincludes,besidesthedevelopmentandtesting,mainlytheapplicationofthesurgearresters.Thesilicontechnology,whichisusedinmediumvoltagebyABBHighVoltageTechnologiesLtd,andthefurtherdevelopingofthemetaloxidematerialopensnewapplicationspheres.Allthesearetakenintoaccountinthenewedition.Wehope,thatyouasareaderwillbesatisfiedwithournewrevisededitionandyouwillfinditusefulforyourpurpose.Wewelcomeamendmentsandsuggestionsinordertomeetallpossiblecustomerneeds.ABBHighVoltageTechnologiesLtdWettingen,July1999Firstpublished:November19942.revisededition:September19953.revisededition:July1999Allrightsreserved.Neitherthebookletorpartsofitmaybeeithercopiedorreproduced,transmittedinanywayortranslatedinfootherlanguageswithoutthepriorpermissionofABBHighVoltageTechnologiesLtd.DivisionSurgeArresters,Wettingen,SwitzerlandABBHighVoltageTechnologogiesLtdForewordinsinVinVinVinVinVinVinVinVinVinVinininVinm/sΩΩtsUUcUEUKUmUpUrUrefUTUTOVZZKLu(t)vδωtimeintervalpeakvalueoftheovervoltageofatravellingwave(mainlygiveninkV)maximumcontinuousoperatingvoltageofthearrester(mainlygiveninkV,rms)maximumovervoltageattheendofanopenline(mainlygiveninkV,peakvalue)maximumovervoltageatcableend(mainlygiveninkV,peakvalue)maximumvoltagebetweenphases(mainlygiveninkV,rms)protectionlevelofthearresteratI(mainlygiveninkV,peakvalue)ratedvoltage(mainlygiveninkV,rms)referencevoltage(mainlygiveninkV,rms)overvoltageatthetransformer(mainlygiveninkV,peakvalue)powerfrequencyovervoltageofalimitedduration(mainlygiveninkV,rms)timefunctionofalightningovervoltagespeedofthetravellingwave,v=300m/µsintheairsurgeimpedanceofadistributionlineconductorZ=300........450surgeimpendanceofacableconductorZ=20......60loadrejectionfactorofageneratorangularfrequencyofthepowerfrequency,at50Hzis=314nKΩΩω2611SSconductorlengthBasicImpulseInsulationLevel(peakvalue)conductorlengthcapacitance(giveninnForuF)earthfaultfactor,CxU/3isthemaximumvoltagebetweenphaseandearthinthecaseofanearthfaultsectionlengthofanoverheadlinebeforethesubstationenergyabsorbedbythearrester(mainlygiveninkJorkJ/kV)dischargeenergyabsorbedbythearrester(mainlygiveninkJ)longdurationcurrentimpulsenominaldischargecurrent(mainlygiveninkA,peakvalue)50Hzfaultcurrent(mainlygiveninkA,rms-value)referencecurrent(mainlygiveninmA,peakvalue)peakcurrentofthestrokecurrent(mainlygiveninkA,peakvalue)timefunctionofthestrokecurrentcoronadampingconstantinductanceofalinetrapprotectivedistancecablelengthMaximumContinuousOperatingVoltage=U(mainlygiveninkV,rms-value)powerlossesofthearresterinthecaseofUperunit,1p.u.=2xUm/3heatflowfromtheactivearresterpartstotheexternalenvironment(cooling)maximumsteepnessofavoltageincrease(mainlygiveninkV/µs)timefunctionofthesteepnessofavoltageincrease(mainlygiveninkV/µs)steepnessofthelightningovervoltageatthepointofthestroke(mainlygiveninkV/µs)three-phasereactivepowerofacapacitorbankwithstandstrengthagainsttemporaryovervoltagesU=TxUtemperaturetimeemUcccTOVc√√√inminkVinminFinminJinAinAinAinHinJinAinAinAinminminVinWinWinV/sinV/sinV/sinVarinCins°aBILbCCdEIii(t)KLeEcInIKIrefLLKMCOVPp.u.QSS(t)SoSKTTt25Indexofsymbolsused10.210.310.410.510.610.710.810.910.10111213OvervoltageprotectionincablesectionsCablesheathprotectionTransformersattheendofcablesTransformerconnectedtoalightningendangeredlineononesideonlyArrestersinmetalenclosedMV-substationGeneratorconnectedtoalightningendangeredMV-lineArresterprotectionformotorsOvervoltageprotectioninlocomotivesArrestersparal