印度某MW電廠電氣作業(yè)指導書102

PT第10頁共10頁InstructionforinstallationandtestThepotentialtransformer1.Relateddocumentationsandstandards1.1.TheChinesestandard(GBJ148-90):Codeforconstructionandacceptanceoftheinstrumenttransformer1.2.TheChinesestandard(GB50150-91):Standardforhand-overtestofelectricequipment1.3.TheChinesestandard(DL408-91):Operationcodeforpowerplantsafety1.4.TheChinesestandard(DL560-95):Operationcodeforelectricsafetyinhighvoltagelaboratory1.5.TheChinesestandard(DL/T5043-95):Designstandardforelectricallaboratoryofthermalpowerplant1.6.TheChinesestandard(DL/T5161.2-2002):Specificationforconstructionqualitycheckoutandevaluationofelectricequipmentinstallation2.Receiptandstorage2.1.Examinethestateofthedevicesandthematerialsreceivedtocheckthatitcorrespondswithwhatwasordered.2.2.Checkallpackagesforexternalsignsofdamage.2.3.Pleasecheckconditionandqualityofthedevicesandthematerials,andcomparethemwiththepackinglist.2.4.Ifonunpacking,whichmustbecarriedoutcarefully,anydamageorirregularityisnoted,notifythiswithindefiniteperiodofreceiptofthegoods,notificationmustindicatetheshippingnotenumber.2.5.Ifthedevicesistobestoredforevenshortperiodsbeforebeingputintoservice,afterreceiptitisadvisabletoputitbackintoitsrelativecontainerandcoveritwithawaterprooftarpaulin.Useadryanddust-freeambientforstoragewithoutanyaggressivechemicalagents.Placethedeviceandanyfixedpartonahorizontalsurfacenotindirectcontactwiththefloor,butonasuitablesupport.2.6.Selectalocationforthedeviceinaclean,dry,vibration-freeareawithmoderatetemperature.2.7.Withregardtolifting,followtheseinstructions:thedevicesmustbeplacedonasturdysurfaceandpreferablyliftedusinganappropriateliftingforktruck.Theuseofropesis,however,permitted:inthiscasetheliftingropesmustbehookedfirmly.3.Installation3.1.Carryoutfollowinginspectionswhentheinstrumenttransformersaretobeinstalled.3.1.1.Positionofratiotapsandpolarityoftheinstrumenttransformersshallconformtothestipulation.3.1.2.Thesecondaryterminalboardsshallbeintact,theleadsbeconnectedfirmly,insulationbewellandmarksbeclear.3.1.3.Nooilleakageontheoillevelgauge,thejointsbetweenbushingsandflanges,andtheoildrainagevalves.3.1.4.Thediaphragmsandmetallicexpandersofthediaphragmtypeconservatorsshallbeintact,andtheboltsonthetopcoversshallbefirm.3.2.Thefittingsurfacesoftheoilimmersedinstrumenttransformersshouldbehorizontal.Thosemountedinparallelshouldbeputinorderandthepolarityindicationoftheinstrumenttransformersinsamegroupshouldbeidentical.3.3.Fortheinstrumenttransformersequippedwithmoistureabsorberstheabsorbentsshouldbedryandoillevelsoftheoilsealsshouldbenormal.3.4.Spacersofplugsinbreathingholesoftheinstrumenttransformersshouldberemovediftheyareprovided.3.5.Forinstrumenttransformerswithvoltageequalizingringstheringsshouldbeinstalledfirmlyandhorizontallywithcorrectdirection.Forthosewithprotectivegapstheclearancesshouldbeadjustedaccordingtomanufacturestipulations.3.6.Followingpartsoftheinstrumenttransformersshouldbeearthedwell:3.6.1.Thecasings3.6.2.Forgradedinsulatedpotentialtransformers,groundingoutletsoftheprimarywindingsshouldbegrounded.3.7.Thecapacitivepotentialtransformersshouldbeinstalledaccordingtothegroupnumberspackagedsuppliedwithproductsandnotexchangeable.Oxidizedlayerofthecontactsurfacebetweencomponentsshouldberemovedandcoatedwithelectriccompositegrease.Rain-proofmeasuresshouldbetakenifinstalltheoutdoordumpers.3.8.Qualitystandardsinstallingthedryinstrumenttransformersareshownasintable3.8.Table3.8.:InstallationofthedryinstrumenttransformersExaminationitemspropertyQualitystandardsMethodsandtoolsofexaminationExaminationofthebodiesMarkofthedataplatesCompleteandclearInspectionAppearanceMainComplete,withoutdamageTerminalboardsofsecondarywiringLeadterminalsSolidconnectionPullExaminationofinsulationMainHighinsulationresistanceChecktestreportsExaminationofvoltageratioandpolarityMainCorrectChecktestreportsInstallationoftheinstrumenttransformersPolaritydirectionUniformforthreephasesInspectionPositionofwiringterminalsAtmaintenancesidesEquipotentialspringsFixtureMainSolidPullContactwiththebusesMainTightandreliableConnectionboltsCompleteandtightCheckbyawrenchEarthofthecasingsMainSolidandreliablePullandconductanceexamination3.9.Qualitystandardsinstallingtheoilimmersedinstrumenttransformersareasshownintable3.9.Table3.9.:InstallationoftheoilimmersedinstrumenttransformersExaminationitemspropertyQualitystandardsMethodsandtoolsofexaminationExaminationofthebodiesMarkofdataplatesCompleteandclearInspectionAppearanceoftheporcelainMainComplete,withoutcrackExaminationofsealMainWithoutoilleakageInspectionOillevelNormalExaminationofthebreathholesMainWithoutblockTerminalboardsofsecondarywiringLeadterminalsFirmconnectionInspectionExaminationofinsulationMainHighinsulationresistanceChecktestreportsExaminationofvoltageratioandpolarityMainCorrectChecktestreportsInstallationoftheinstrumenttransformersPolaritydirectionUniformforthreephasesInspectionDiaphragmtypeconservatorsExaminationofthediaphragmsMainPerfectInspectionExaminationoftheboltsontopcoversCompleteandtightCheckbyawrenchCapacitivepotentialtransformersAssemblynumberMainInaccordancewithmanufacturestipulationCheckdependonmanufacturestipulationContactsurfacebetweenassembliesWithoutoxidizedlayer,coatelectriccompoundgreaseInspectionVoltageequalizingringsAppearanceClean,withoutdamageInspectionClearancewiththeporcelainskirtsUniformConnectionboltsCompleteandtightCheckbyawrenchEarthEarthofthecasingsSolidandreliablePullandconductanceexaminationEarthforgradedinsulationorcapacitivePTMainReliableandinaccordancewiththemanufactorystipulationEarthoffinalscreensandironcoresofthecapacitivePTMainSolidandconductiveMarkofphasecolorsCorrectandcompleteInspection4.Test4.1.Measureinsulationresistance4.1.1.Methodandsequence4.1.1.1.Disconnectallwiresbetweenmeasuredequipmentandotherobjects,thendischargebymeansofearthedwire,theperiodofdischargingshouldexceed1min.4.1.1.2.Recordthetemperatureoftheequipment.4.1.1.3.Voltagelevelsofthemeg-ohm-metersformeasuringinsulationresistanceshouldaccordwiththefollowing:use250Vmeg-ohm-metersforelectricdevicesorcircuitswhichratedvoltagesarebelow100V,500Vmeg-ohm-metersfor100V~500V,1000Vmeg-ohm-metersfor500V~3000V,2500Vmeg-ohm-metersfor3000V~10000V,2500Vor5000Vmeg-ohm-metersfor10000Vandabove.4.1.1.4.Otherwindingswhicharen’tmeasuredmustbeshortcircuitandgrounded.4.1.1.5.Theequipmentshouldbedischargedfullyintothegroundafterthemeasurement.Periodofdischargingshouldexceed2min.4.1.2.Measureinsulationresistancesoftheprimarywindingstothesecondarywindingsandthecasingsandthoseofthesecondarywindingstoothersecondarywindingsandthecasings.Noapparentdifferencesbetweenmeasuredvaluesandthemanufactorytestdata.4.2.ACvoltagewithstandtestsforthewindingsandbushingstothecasings4.2.1.Methodandsequence4.2.1.1.CapacityandvoltageoftheACvoltagewithstandtesterareasshowninthetable4.2.1.1.Frequenciesofthepowersuppliesare50Hz.Table4.2.1.1:CapacityandvoltageofACvoltagewithstandtesterTesteddevicesCapacity(kVA)Voltage(kV)200~600MWgenerators12050/0.38125MWandbelowgenerators5035/0.3835kVelectricdevices50100/0.3820kVelectricdevices870/0.3810kVelectricdevices535/0.38Lowvoltageelectricdevices110/0.384.2.1.2.AssumeUisthetestvoltageinvolt,thenthewaterresistorR1inΩforprotectthetesteddevicemaybecalculatedbyformulaR1=K1U,whereK1=0.5~1Ω/V;thelimitresistorR2inΩforprotectthegapmaybecalculatedbyformulaR2=K2U,whereK2=1Ω/V.4.2.1.3.Raisethevoltageinno-loadtestafteradjustingthegapforover-voltageprotectioninordertothegapdischargewhenno-loadvoltagereaches1.1U,whereUistestvoltage.Thenraisevoltagetotestvalue,maintainitfor1min.Thegapshouldnotdischarge.Repeatthisoperationthreetimes.4.2.1.4.Thesettingoftheover-currentprotectionrelayis1.3timesthecapacitivecurrentathighvoltageside.4.2.1.5.Allnon-testedwindingsandcircuitsmustbeshortcircuitandgroundduringtest.Takeoffallelectronicdevices.4.2.1.6.Periodfromhalfofthetestvoltagetofullvaluecanbe10~15secondsandthefullvoltageshouldbemaintainedfor1min.Itshouldthenbereducedataratethatwillbringitto1/4valueorlessinnotmorethan15s.4.2.2.StandardsofACvoltagewithstandtestsontheprimarywindingsrefertotable4.2.2.Table4.2.2.:StandardsofACvoltagewithstandtestsontheprimarywindingsRatedvoltage(kV)6.62033132220400Testvoltage(kV)21.94568.4215.23565224.2.3.StandardsofACvoltagewithstandtestsonthesecondarywindingstoothersecondarywindingsandthecasingsare2kV.4.2.4.MultiplefrequencyinducedACvoltagewithstandtestsforthecascadingPTandmediumvoltagetransformersinthecapacitivePTcanbecarriedoutifinsulationpropertyispoor.4.2.4.1.VoltagestandardsofmultiplefrequencyinducedACvoltagewithstandtestsare85%ofmanufactorytestvoltages.4.2.4.2.Testdurationsinsecondaret=60×100/fwherefisfrequencyofthetestpowersupplyinHzwhenfis150Hzandabove.4.2.4.3.Frequencyofthetestpowersupplyshouldbelowerthan400Hz.Testdurationshouldbemorethan20s.4.2.4.4.Measureno-loadcurrentsandlossesatprimaryratedvoltagebeforeandafterthemultiplefrequencyinducedACvoltagewithstandtest.Noapparentdifferencesbetweentwomeasuredvalues.4.2.4.5.CarryoutcolorspectrumanalysesfortheinsulationoilbeforeandafterthemultiplefrequencyinducedACvoltagewithstandtest.Noapparentdifferencesbetweentwomeasuredvalues.4.3.Measuretangentofdielectriclossangletgδ(%)ofprimarywindingstogetherwithbushingsofthe132kV,220kVand400kVinstrumenttransformers.4.3.1.Tangentofdielectriclossangletgδ(%)oftheoilimmersedPTshouldbelessthanthestipulationsasshownintable4.3.1.Table4.3.1.:Tangentofdielectriclossangletgδ(%)oftheoilimmersedPTTemperature(℃)510203040tgδ(%)2.02.53.55.58.04.3.2.Measuredtgδ(%)shouldnotbemorethan130%ofthemanufactorytestvalueswhenthetestvoltageis10kV.4.4.Testofinsulationoilcanbecarriedoutifinsulationpropertyispoor.4.4.1.Dielectricstrengthtest4.4.1.1.RatedvoltageoftheACpowersourcefortestis60kV.4.4.1.2.Thedielectricstrengthtestcupismadewithtwoparallelroundelectricpoles.Diameterofthepolesis25mm.Thicknessis6mm.Distancebetweentwopolesis2.5mm.4.4.1.3.Testvoltagecanbeincreasedfrom0Vuntiltheoilgapbreakdown.Theincreasingrateis3kV/s.Recordthebreakdownvoltage.Carryoutnexttestafter5min.forfivetimes.Thedielectricstrengthisameanofthefivebreakdownvalues.4.4.1.4.Thedielectricstrengthcannotbelowerthan25kVfor15kVinsulationoil,35kVfor20~35kV,40kVfor60~220kV,50kVfor330kV,60kVfor500kV.4.4.2.Measurementofthetangentofdielectriclossangle,i.e.tgδ(%).4.4.2.1.Cleantheoilcupuntilthetgδ(%)islessthan0.01%foremptycup.4.4.2.2.Measuretgδ(%)oftheoilat90℃.Recordthemeasuredvalue.4.4.2.3.Testagainafter15min.Differencebetweentworesultsshouldbelessthan10%.Thetgδ(%)at90℃isameanofthetwomeasuredvalues.4.4.2.4.Thetgδ(%)ofthetestedinsulationoilat90℃mustbelessthan0.5%.4.4.3.Measurethesurfacestretchingforceoftheinsulationoilat25℃.Measuredvaluecannotbelessthan35mN/m.4.4.4.Measuretheacidvalueoftheinsulationoil.ContentofKOHin1goilcannotbemore0.03mg.4.4.5.PHvalueoftheinsulationoilcannotbelessthan5.4.4.4.6.Thereisn’tanymechanicalimpurityintheinsulationoil.4.4.7.Flashpointoftheinsulationoilcannotbelowerthan140℃.4.4.8.Contentofwaterininsulationoilcannotbemorethan15ppmfor132kV,220kVPT,10ppmfor400kVPT,whereppmisabbreviationofpartspermillion.4.4.9.Carryoutcolorspectrumanalysesforcontentofgasintheinsulationoiloftheinstrumenttransformers.Noapparentdifferencebetweenmeasuredvaluesandmanufacturetestvalues.4.4.10.Insulationoiltestrecordisasshownintable4.4.10.Table4.4.10.:TestrecordofinsulationoilintheinstrumenttransformerProjectnameTransformertypeRatedcapacityRatedvoltageRatedcurrentCoolmannerTrademarkoftheinsulationoilTotalweightoftheinsulationoilManufactureManufacturingnumberManufacturingdateTestitemsStandardsResultsRemarkSurfacestretchingforce≥35mN/mAcidvalue≤0.03mg(KOH)/gpHvalue≥5.4MechanicalimpurityNoFlashpoint≥140℃Dielectricstrengthtest≥25kVfor15kVandbelow;≥35kVfor20~35kV;≥40kVfor60~220kV;≥50kVfor400kV;≥60kVfor500kVTangentofdielectriclossangletgδ(%)≤0.5%at90℃Watercontent≤15ppmfor132kV,220kV;≤10ppmfor400kV;GascontentAcceptanceopinionSignatureDateConstructiongroupConstructionteamQualitydepartmentSupervisorydepartment4.5.MeasureDCresistancesofthePTprimarywindings.Noapparentdifferencesbetweenmeasuredvaluesandthemanufactorydataorthatofsametypeproducts.4.6.Measureno-loadcurrentsandexcitationcharacteristiccurvesof1000VandabovePTunderratedvoltage.Noapparentdifferencesbetweenmeasuredvaluesandthemanufactorydataorthatofsametypeproducts.4.7.Measureconnectionvectorgroupsofthethreephaseinstrumenttransformersandterminalpolarityofthesinglephaseinstrumenttransformersinaccordancewiththedataplatesandsignsonthecasings.4.8.Measuretransformationratiosoftheinstrumenttransformersinaccordancewiththedataplates.4.9.Measureinsulationresistanceoftheironcoreclampingboltswitha2500Vmeg-ohm-meter.Measurementiscarriedoutonlyontheironcoreclampingboltsexposedoraccessibleduringbodyinspection.Theconnectorsshallbeopenedduringmeasurementifthethroughboltconnectedwithironcoreatoneend.4.10.Partialdischargetest4.10.1.Methodofmeasuringthedischargequantity4.10.1.1.Thetestpowersourcecanbeamediumfrequencygeneratorora150Hzpowersource.4.10.1.2.AssumeUisthevoltagedropattwoendsofthetestedobject,thenthedischargequantityQ=CxU,whereCxiscapacitanceofthetestedobject.4.10.1.3.ThedischargequantityQisdefiniteintegralofthedischargecurrentthroughthetestedobjectindefiniteperiod.4.10.2.AssumeUmismaximumroot-mean-squarevalueofvoltageofthetestedtransformerthenpermittedlevelsofpartialdischargequantitiesfortheinstrumenttransformersareasshownintable4.10.2.Table4.10.2.:PermittedlevelsofpartialdischargequantitiesfortheinstrumenttransformersEarthmannerTypeofinstrumenttransformerPre-suppliedvoltage(t≥10s.)Measuringvoltage(t≥1min.)InsulationtypeApparentdischargequantity(pC)NeutralpointinsulationsystemorneutralpointresonanceearthsystemCurrenttransformersandphase-to-groundpotentialtransformers1.3Um1.1Um/√3Liquidimmersed20Solid100Phase-to-phasepotentialtransformers1.3Um1.1UmLiquidimmersed20Solid100NeutralpointeffectiveearthsystemCurrenttransformersandphase-to-groundpotentialtransformers0.8×1.3Um1.1Um/√3Liquidimmersed20Solid100Phase-to-phasepotentialtransformers1.3Um1.1UmLiquidimmersed20Solid1004.10.3.EnergizethetestedcouplingcapacitorsofthecapacitivePTaccordingwithfollowingsequence:4.10.3.1.0.8×1.3Um=1.04Umfor10s.4.10.3.2.1.1Um/√3for1min.4.10.3.3.Partialdischargequantitiesshouldbelessthan10pC.4.11.Testofthecapacitors4.11.1.Measureinsulationresistancesofthecapacitorsbetweentwopolesandtoground.4.11.2.Measuretangentsofdielectriclossangletgδ(%)andcapacitancesofthecapacitorsandmeasuredvaluesshouldnotexceed±5%ofratedcapacitances.5.Puttingintoservice5.1.Generaldescription5.1.1Whenfinishedwiththeoriginalinstallationandallmodifications,conductacompleteoperationtestontheentireinstallationtoverifycompliancewithapplicablestandards.Testingshouldbeconductedbyafactory-trainedtechnicianinthepresenceofarepresentativeofthemanufacturerandtheowner’srepresentative.Followproceduresoutlinedintherelatedstandard.5.1.2.Periodictestingandservicingofthesystem,alldevices,andanyotherassociatedequipmentisessentialtoensureproperandreliableoperation.Testandservicethesystemandthedeviceaccordingtotheschedulesandproceduresoutlinedinthemanufacturer’smanuals.5.1.3.Betweenformalperiodictestingandservicingintervals,therelatedoperationchecksshouldbeperformedfordefiniteperiod,orfrequentlywhenrequiredbytheowner.5.2.Testreportsofthepotentialtransformersareasshownintable5.2.Table5.2.:TestreportsofthepotentialtransformersProjectnameSecondarycircuitnameTypeofPTSpecificationofPTRatedvoltageRatedcapacityRatedratioInsulationtypeManufactoryManufacturenumberManufacturedateTestitemsTestdataResultsRemarkInsulationresistancePrimarywindingtosecondarywindingandcasingSecondarywindingtoothersecondarywindingandcasingACvoltagewithstandtestPrimarywindingSecondarywindingTangentofdielectriclossangletgδ(%)TestofinsulationoilDCresistanceofprimarywindingNo-loadcurrentExcitationcharacteristicThreephasevectorgrouporsinglephaseoutletpolarityTransformationratioInsulationresistanceofironcoreclampingboltsPartialdischargequantityTestconclusionRepresentativeoftestersSignatureDate6.Safetyprecautions6.1.Theinstallationhastobecarriedoutbyqualifiedpersonalfollowingtheinstructionofthemaker.Onlyqualified,authorizedpersonsshouldcarryoutelectricalwork.Wiringshouldbeperformedbythequalifiedpersonnelonly.6.2.Adisconnectswitchmustbeinstalledtobreakallcurrentcarryingconductors.Beforemakinganyelectricalconnectionensurethatthemainswitchisoff,alloftheelectricalpowerlinestotheequipmentmustbeisolated.Failuretoobservethisprecautionmayresultinseriouspersonalinjury.6.3.Allmainscablesandsignalcablesmustbeconnectedinexactaccordancewiththeoperatinginstructionstoavoidtheriskofelectricshock.6.4.Whilethedevicesarepowered,apotentiallylethalshoc