高電壓設備測試（High Voltage Equipment Testing）（英文版） 課件全套 何發(fā)武 Project 1 Overview - Project 4 New Technology

《HighVoltageEquipmentTesting》HighVoltageSafetyOperatingWorksheet：TableofContents01Followme02Workshop03Training01FollowmeFollowmeHigh-voltagetestingisahigh-risktaskinelectricaltesting.Duringtheprocessofhigh-voltagetesting,itisnecessarytocomplywithrelevantnationalsafetyregulationstoensurepersonalsafetyandthesafetyofthepowersystem.Themainstandardforhigh-voltagetestingisreferencedfromthe“StandardforElectricalEquipmentInstallationEngineering-ElectricalEquipmentHandoverTesting”（GB50150–2016）.Ⅰ.SafetyDistanceThesafetydistancereferstotheminimumairgapmaintainedbetweentheoperatorandtheliveobjecttoensurepersonalandequipmentsafety.Thesizeofthesafetydistancevariesdependingonthevoltagelevel,equipmenttype,installationmethod,andweatherconditions.AccordingtothecurrentsafetyregulationsoftheStateGridpowerplantandsubstation,thesafetydistancesforliveequipmentare0.7

mfor10

kV,1

mfor35

kV,1.5

mfor110

kV,3

mfor220

kV,4

mfor330

kV,and5

mfor500

kV.Ⅰ.SafetyDistanceThesafetydistanceforoperatingnon-power-offequipmentintheStateGrid’s10

kVdistributionstationisshowninFigure1-1.Whenthedistancebetweentheliveobjectandthehumanbody,equipment,andlivewiresduringtestingdoesnotmeettherequirements,temporarybarriers,insulatingshields,insulatingmats,etc.,mustbeinstalledforisolation.Ifsparksordischargesoundsoccurduringthetesting,itindicatesthatthedistanceisnotsufficient.Stopthetestimmediately,adjustthedistance,wipetheinsulationsurface,andtestagain.Figure1-1Ⅱ.SafetyRegulationsHigh-voltagetestsafetyoperatingprocedures:poweroutage,powertesting,grounding,hangingsignage,eachstepmustbeperformedinstrictaccordancewiththeorder.Onepersoninoperation,onepersoninguard.Accordingtothecontentoftheworkpermission,thepowerlineandequipmentshouldbeconfirmedtocutofffromthepower.Thecorrespondingvoltagelevelelectroscopeshouldbeusedintheelectricitytest,andtheelectricityshouldbetesteditembyitemattheinstallationofthegroundingwireortheclosingofthegroundingswitch.Whengrounding,afterconfirmingthereisnovoltage,thehigh-voltagelinesandequipmentshouldbegroundedandshort-circuitedimmediately,andalllinesthatmaybereverselypoweredshouldbegrounded.Ⅱ.SafetyRegulationsTheclimateconditionsforhighvoltageinsulationtestingshouldnotbelowerthan+5C,andtherelativehumidityoftheairshouldgenerallynotexceed80%.Thetestingsequenceof“non-destructivetestingbeforedestructivetesting”shouldbefollowed.Iftheweatherhumidityistoohigh,theinsulationsurfacemaycondenseorformawaterfilm,whichwillreducethesurfaceinsulationresistance,greatlyincreasethesurfaceleakagecurrent,andalsocausedistortionoftheelectricfielddistributionontheinsulationsurface,resultingincoronadischarge,affectingthemeasurementresults,andrequiringtestingtoberescheduled.Ⅱ.SafetyRegulationsBeforeandafterthetesting,establishsafetymonitoringandprotectionsystems.Thetestingpersonnelshouldwearnecessaryprotectiveequipmentbeforethetesting(“two-wearingandthree-carrying”:wearingworkinguniform,wearinginsulatingboots,carryingsafetyhelmets,carryinginsulatinggloves,andcarryingvoltagedetectors).Thetestingsiteshouldsetupfencesandhang“Stop,HighVoltageDanger”signsfacingoutward.Foroperationsabove2

m,adequatefallprotectionmeasuresshouldbetaken.Personnelandequipmentshouldmaintainasafetestingdistance,asshowninFigure1-2.Figure1-202WorkshopⅠ.WorkspecificationThesafetyleveloftheworkersmustnotbelowerthanlevelthree.Workersshouldfastentheirseatbelts,wearsafetyhelmets,andtakeanti-slipmeasures.Workcanonlybecarriedoutinclearweatherconditions,startingfrom9:00AM.Onesupervisorcanonlyoverseeonegroupofworkers.Groundingworkersmustwearsafetyhelmets.Thetoolscarriedbytheworkersmustbeplacedintoolbags,andthebagsmustbesecurelyfastenedtopreventtoolsfromfallingandinjuringgroundworkers.Ⅰ.WorkspecificationThepowersupplyinthehigh-voltageroommustbecompletelyshutoff,andpropersafetymeasuresmustbetakenbeforeworkcancommence.Workshopleadersmustbepresenton-sitetoensuresafety.Whenchangingthebusbarorsupportingporcelainbottles,payattentiontopersonalandequipmentsafetytopreventinjuriesandequipmentdamage.Ⅰ.WorkspecificationWhenconductinghigh-voltagetestsonelectricalequipment,afencemustbesetuparoundtheworkarea,withasignhangingonthefencewith“NoEntry,HighVoltageDanger!”Guardsshouldbestationedthere.Onlyoneworkgroupisallowedtoperformhigh-voltagetestsononepieceofequipmentwithinaspecificelectricalconnection.Agroundingwireshouldbeinstalledonthemaintenancesideofthedisconnectionpoint,andasignwith“NoEntry,HighVoltageDanger!”shouldbehungonthehigh-voltagetestside,facingthemaintenanceworkarea.Ⅰ.WorkspecificationIndividualsarenotallowedtoenterhigh-voltagecompartmentsorprotectivefencesalone.Thedistancebetweenindividualsandlivepartsmustbeequaltoorgreaterthanthevaluespecified.Whentherearehigh-voltageequipmentneartheworkarea,fencesshouldbesetuparoundtheworkareawithcorrespondingsignshanging.Theremustbededicatedpersonneltosupervisethework,andoperatorsmustuseinsulatingtoolswhilestandingoninsulatingmats.Short-circuitingofliveterminalsmustbeavoided.Measuresshouldbetakentoensurethatthesecondarysideofpotentialtransformersdoesnotshort-circuitandthemutualsecondarysideofcurrenttransformersdoesnotopencircuit.Ⅰ.WorkspecificationWhenthedistancebetweenworkersandlivepartsofhigh-voltageequipmentequalsthespecifiedsafetydistance,thefollowingoperationsareallowedtobeperformedonthehigh-voltageequipmentwithoutpoweroutage:replacingsiliconeandtakingoilsamples.Inanycircumstances,workersmustmaintainthespecifiedsafetydistancefromliveparts.Thesafetylevelofworkersandsupervisorsmustnotbelowerthanleveltwo.Ⅰ.WorkspecificationBeforecarryingoutanyworkrelatedtohigh-voltageelectricalequipment,powerworkersneedtothoroughlyreadtheequipmentusermanual.Duringtheworkprocess,appropriatesafetyprecautionsshouldbetaken,andrelevantoperatingspecificationsmustbestrictlyfollowedtoprotectone’sownlife.Fixedplacementofinstrumentsshouldbedoneaccordingtotheinstrument’sfunctionalclassification,asshowninFigure1-3.Figure1-3Ⅰ.WorkspecificationDuringhigh-voltagetesting,thetestsupervisorshouldbeanexperiencedstaff.Beforestartingthetest,thetestsupervisorshouldprovidedetailedinstructionsonsafetyprecautionstoalltestpersonnelandassigndedicatedpersonnelforsupervision.Themetalcasingofthetestequipmentshouldbereliablygroundedusingmulti-strandedsoftbarecopperwirewithacross-sectionalareanotlessthan25

mm2.Thehigh-voltageleadsshouldbekeptasshortaspossibleandsupportedsecurelywithinsulationmaterialsifnecessary.Thepowerswitchofthetestequipmentshouldbeadouble-poleswitchwithaclearlyvisibledisconnectpoint.Intheoperationcircuitofthetestequipment,inadditiontothepowerswitch,azeropositionswitchshouldbeconnectedinseries,andanoverloadautomatictrippingdeviceshouldbeinstalled.Beforeandafterthewithstandvoltagetestoflargecapacitorequipmentorcapacitors,sufficientgroundingandshort-circuitdischargeshouldbecarriedout.Ⅰ.WorkspecificationWhenperformingvoltagetestingonhigh-voltageequipmentorinstalling/removinggroundingwires,itisnecessaryfortwopersonstoworksimultaneously.Theoperatorandthesupervisormustwearinsulatingbootsandsafetyhelmets,andtheoperatormustwearinsulatinggloves.Duringvoltagetesting,anappropriateandqualifiedelectroscopewithsuitablevoltageratingsmustbeused.Theelectroscopeshouldfirstbetestedonenergizedequipmenttoconfirmitsproperfunctioning,andthenvoltagetestingcanbeperformedonde-energizedequipment.Finally,aretestshouldbeconductedonenergizedequipment.Ⅰ.WorkspecificationDuringvoltagetesting,allincomingandoutgoinglinesoftheequipmentbeingtestedshouldbechecked.Highvoltagetestingcaneliminateerrorssuchasstopwrongelectricityornopoweroutage,andpreventhanginggroundwireinthecaseoflive,asshowninFigure1-4,Figure1-5.Figure

1-4

Figure

1-5Ⅰ.WorkspecificationThereshouldbepersonnelsupervisionduringtheinstallationandremovalofgroundingwires,asshowninFigure11-6.Theinstalledgroundingwireshouldhavegoodcontactandreliableconnection.Thegroundingwireshouldbeconnectedtothegroundingendfirst,andthentotheconductorendduringinstallation.Thesequenceisreversedfortheremovalofthegroundingwire.Figure1-6Ⅱ.NotesInstallationandremovalofgroundingwireswithonepersonoperatingandanotherpersonsupervising.Thegroundingwireshallbeusedwithspecialclips,firmlyconnected,goodcontact,strictlyprohibitedwinding.Thegroundingwireshouldusebarecoppersoftstrandwithacross-sectionalareaofnotlessthan25

mm2(notlessthan95

mm2forDCsystem),andthereshouldbenobrokenstrands,loosestrandsandjoints.Ⅱ.NotesAfterconnectingthegroundingwireforvoltagetesting,“ProhibitedfromClosingOperation,PersonnelWorking”signsshouldbehungontheoperatinghandlesofcircuitbreakersanddisconnectswitches.Whileworkingonindoorequipment,barriersshouldbeinstalled,and“NoEntry,HighVoltageDanger!”signsshouldbedisplayed.Itisprohibitedforanyonetoworkaloneinhigh-voltagerooms,high-voltagecabinets,orcontainerequipment.Whileworkinginconfinedspaces,itisnecessarytoensuregoodventilation.03Training

TrainingExercise1.Requirementsforhigh-voltageequipmentvoltagetesting:_____________________________________________________________________________Exercise2.Requirementsforinstallationandremovalofgroundingwires:_____________________________________________________________________________《HighVoltageEquipmentTesting》Thissectionisover.《HighVoltageEquipmentTesting》HighVoltageInsulationTools主講人：何發(fā)武（副教授）OperatingWorksheet：TableofContents01Followme02Workshop03Training01FollowmeⅠ.ClassificationofInsulationToolsHighvoltagesafetytoolsarethebasicequipmentusedtodirectlyprotectthesafetyofelectricians.Highvoltagesafetytoolsareclassifiedintoinsulationsafetytoolsandgeneralprotectivesafetytools,andinsulationsafetytoolscanbefurtherdividedintobasicsafetytoolsandauxiliarysafetytools.Basicsafetytools:Theinsulationstrengthshouldbeabletowithstandtheworkingvoltageforalongtimeandensurethepersonalsafetyoftheworkerswhenovervoltageoccursattheworkingvoltagelevel.Auxiliarysafetytools:Iftheinsulationstrengthcannotwithstandtheworkingvoltageofelectricalequipmentorcircuits,itisnecessarytostrengthentheprotectionfunctionofbasicsafetytoolstopreventtheharmofcontactvoltage,stepvoltage,andarcburningtotheoperators.Ⅰ.ClassificationofInsulationToolsInhigh-voltageinsulationsafetytools,basicsafetytoolsincludeinsulatingrods,insulatingpliers,andvoltagetesters;auxiliarysafetytoolsincludeinsulatinggloves,insulatingboots,insulatingmats,insulatingplatforms,andinsulatingblankets,etc.Inlow-voltageinsulationsafetytools,basicsafetytoolsincludeinsulatinggloves,toolswithinsulatinghandles,andlow-voltagevoltagetesters.Auxiliarysafetytoolsincludeinsulatingtables,insulatingmats,insulatingshoes,andinsulatingboots,etc.Evenforthesameinsulatinggloves,theclassificationisdifferentinhighandlowvoltageapplications.Ⅰ.ClassificationofInsulationToolsPortablegroundingwires,temporarybarriers,signs,warningsigns,protectivegoggles,safetybelts,woodenladders,andfootbuckles,etc.,aregeneralsafetytoolsthatpreventworkersfrombeingshocked,arcburned,andfallingfromheights.Theyarenotinsulationtoolsthemselves.Ⅱ.OverviewofInsulationToolFunctionsThenames,functions,andfiguresofcommontestingsafetytoolsareshowninTable1-1.ClassificationNamesandfunctionsofinsulatingtoolsExampleInsulatingprotectiveequipmentSafetyhelmets(Personalprotectiveequipmentforheadprotectionofworkersinsituationswherethereisariskoffallingobjectsorpersonnel)InsulatedBoots(Basicpersonalsafetyequipmentforlowvoltagecircuittesting)Table1-1

Names,functions,andexamplesofcommontestingsafetytoolsⅡ.OverviewofInsulationToolFunctionsThenames,functions,andfiguresofcommontestingsafetytoolsareshowninTable1-1.ClassificationNamesandfunctionsofinsulatingtoolsExampleInsulatingprotectiveequipmentInsulatedGloves(Basicpersonalsafetyequipmentforlowvoltagecircuittesting)InsulatingMat(Auxiliarysafetyequipmentforpersonnelandequipmentduringhighvoltagetesting)Table1-1

Names,functions,andexamplesofcommontestingsafetytoolsⅡ.OverviewofInsulationToolFunctionsThenames,functions,andfiguresofcommontestingsafetytoolsareshowninTable1-1.ClassificationNamesandfunctionsofinsulatingtoolsExampleInsulatingprotectiveequipmentInsulatingBlanket(Auxiliarysafetyequipmentforpersonnelandenergizedequipmentduringliveoperations)HighVoltageInsulatinguniform(Auxiliarysafetyequipmentforpersonnelandenergizedequipmentduringliveoperations)Table1-1

Names,functions,andexamplesofcommontestingsafetytoolsⅡ.OverviewofInsulationToolFunctionsThenames,functions,andfiguresofcommontestingsafetytoolsareshowninTable1-1.ClassificationNamesandfunctionsofinsulatingtoolsExampleInsulatingprotectiveequipmentHighVoltageInsulatinguniform(Auxiliarysafetyequipmentforpersonnelandenergizedequipmentduringliveoperations)HighvoltagepowertestandgroundingdeviceHighVoltageElectroscope(Usedtocheckifelectricalequipmentorcircuitsareenergizedanddetectthepresenceofhigh-frequencyelectricfields)Table1-1

Names,functions,andexamplesofcommontestingsafetytoolsⅡ.OverviewofInsulationToolFunctionsThenames,functions,andfiguresofcommontestingsafetytoolsareshowninTable1-1.ClassificationNamesandfunctionsofinsulatingtoolsExampleHighvoltagepowertestandgroundingdeviceGroundingwire(Safetytoolusedduringtestingorconstructiontopreventelectricshockhazards)Insulatingclamps(Usedforinstallationandremovalofhighvoltagefusesin35

kVandbelowpowersystem)Table1-1

Names,functions,andexamplesofcommontestingsafetytoolsⅡ.OverviewofInsulationToolFunctionsThenames,functions,andfiguresofcommontestingsafetytoolsareshowninTable1-1.ClassificationNamesandfunctionsofinsulatingtoolsExampleHighvoltagepowertestandgroundingdeviceHighVoltageDCdischargeRods(Inthehighvoltagetest,especiallyaftertheDCwithstandvoltagetest,theaccumulatedchargeonthesampleisdischargedtothegroundtoensurepersonalsafety)HighVoltageInsulationOperatingPole(Usedforopeninghighvoltagedisconnectorswitchesordrop-outtypefuses,aswellasinsulationandtestingmeasurementsonhighvoltageequipment)Table1-1

Names,functions,andexamplesofcommontestingsafetytoolsⅡ.OverviewofInsulationToolFunctionsThenames,functions,andfiguresofcommontestingsafetytoolsareshowninTable1-1.ClassificationNamesandfunctionsofinsulatingtoolsExampleHighvoltagepowertestandgroundingdevicePhasedetector(Usedtodetecthighvoltage,phasesequenceverificationofthree-phaselines,andwhetherthepowersupplyontheloopnetworksideisinphase)Table1-1

Names,functions,andexamplesofcommontestingsafetytools02WorkshopⅠ.InsulatinggloveinspectionInsulatingglovescanpreventacertaindegreeofelectricshockinjury.Whenthecurrentleakedfromthehumanbodyiswithinthesaferange,itissafe.However,iftheleakagecurrentistoolarge,itcanalsocausehumaninjury.Beforeusinginsulatinggloves,checkwhethertheyhaveexceededtheireffectiveuseperiod.Conductanexternalinspectionbeforeuse.Useadryclothtowipeoffthesurfacedirtanddustontheinsulatinggloves.Checkthesurfaceoftheinsulatingglovesforscratchesandinspecttheinsulationrubberforagingandbonding.Ifdamagesuchasstickiness,cracks,leaks,bubbles,andbrittlenessisfound,itisforbiddentousethegloves.Ⅰ.InsulatinggloveinspectionInspectionmethod:Rolltheglovestowardthefingers.Ifthefingersbulgewithoutleaking,theyaregood;alternatively,aportableinsulationglovetestercanbeused.Inflatethegloveswiththetesterandcheckforleaks.Duringtheuseofinsulatinggloves,thecuffsoftheuniformmustnotbeexposedoutsidethegloves.Afterused,cleanandairdrythegloves,keepthemdryandclean,andsprinklesometalcumpowdertoavoidadhesion.Insulatingglovesshouldbestoredinadryandcoolinsulatingsafetytoolcabinet.Itshouldnotbetoocoldortoohot,andthetemperatureshouldbemaintainedbetween15C–35Cwitharelativehumidityof5%–80%topreventpolymeragingandreduceinsulationperformance.Keeptheglovesseparatefromothertoolsanddonotstackanyobjectsonthemtopreventpuncturingthegloves.Ⅰ.InsulatinggloveinspectionInsulatingshoes(boots)mainlyundergoexternalsizeinspections.Iftherearedamagesonthesurface,theshoesoleshavewornoutslip-resistantteeth,andtheoutersolehaswornthroughtheinsulationlayer,theycannotbeusedagain.Ⅱ.RequirementsforwearingliveoperationinsulatinguniformThereisadifferencebetweeninsulatinguniformandconductiveuniform.Insulatinguniformcanwithstandhighvoltagesbelow7

kV,anditisresistanttohighvoltage,flameretardant,acidandalkali-resistant.Insulatinguniformismadeofnylon-coatedfabricwithinsulationproperties,primarilyusedforphysicalprotectionduringliveoperations.Ⅱ.RequirementsforwearingliveoperationinsulatinguniformConductiveuniform,alsoknownasliveoperationshieldingclothingorequipotentialvoltageclothing,isworntoformanequipotentialshieldingsurfaceontheoutersurfaceofthehumanbodyinahigh-voltageelectricfield.Itprotectsthebodyfromthedangersofhigh-voltageelectricfieldsandelectromagneticwaves,primarilyusedwhenenteringahigh-voltageelectricfieldduringthemaintenanceofhigh-voltagelines.Conductiveuniformismadeofuniformconductormaterialandfibermaterial.Thecompletesetofshieldinguniformshouldincludeajacket,pants,hat,socks,gloves,shoes,aswellascorrespondingconnectingwiresandconnectors.Ⅱ.Requirementsforwearingliveoperationinsulatinguniform(1)Beforewearinginspecttheprotectiveequipment.Priortouse,pressurizethehigh-voltageinsulatingglovesandbootswithairtocheckforpinholedefects.Inspecttheinsulatingsleeves,shouldercapes,andinsulatinguniformforpunctureholesandscratchesbeforeuse.Iftherearesignificantdefectsintheprotectiveequipment,itsuseisstrictlyprohibited.(2)Operationperiodoperatormustwearinsulatinghelmets,insulatingboots,insulatinguniform,insulatinggloves,andouterprotectiveglovesonthegroundbeforeenteringtheinsulatingbucket.On-sitesafetyinspectorswillconductinspections.RefertoFigure1-7forillustration.Figure1-7

Ⅱ.Requirementsforwearingliveoperationinsulatinguniform(3)Whenremovinginsulatingglovesandinsulatingcapsaftertheliveoperation,personnelshouldpayattentiontooverheadlivewiresandmaintainasafedistancefromliveconductorsinthevicinity.03Training

TrainingExercise1.Inspectioncontentsofhigh-voltageinsulatingrods:_____________________________________________________________________________Exercise2.Requirementsforinspectionofhigh-voltageelectroscope:_____________________________________________________________________________《HighVoltageEquipmentTesting》Thissectionisover.《HighVoltageEquipmentTesting》HighVoltageTestingandInstruments主講人：何發(fā)武（副教授）OperatingWorksheet：HighVoltageTestingItemsTableofContents01Followme02Workshop03Training01FollowmeFollowmeHigh-voltageequipmentinsulationdefectsaremainlyclassifiedintotwotypes:centralizeddefectsanddistributeddefects.Centralizeddefectsrefertospecificissuessuchasmoistureingress,mechanicaldamage,insulationinternalbubbles,andporcelaininsulatorrupture,whichposesignificantsafetyrisks.Distributeddefectspertaintooverallinsulationperformancedegradationresultingfrommoistureingress,overheating,andprolongedoverload.Itisacommonformofinsulationdeteriorationthatprogressesslowlyandcanbedetectedthroughperiodictesting.FollowmeThepurposeofhigh-voltagetestingistoanalyzeandevaluatevariousperformanceaspectsbasedontestresults,eliminateandpreventlatentdefects,promptlyidentifyandaddressequipmentaginganddegradationissues,andenhanceequipmentreliabilityduringoperation.High-voltagetestingcanbedividedintoinsulationtestingandcharacteristictesting,dependingonthenatureofthetestitems.Insulationtestinginvolvesinspectionsofelectricalequipmentinsulationcondition,includingexternalinsulationinspection,insulationconditiondatatesting,andwithstandvoltagetests.Characteristictesting,ontheotherhand,referstoelectricaltestsconductedbeyondinsulationtesting.Itsobjectiveistoverifywhetherthetechnicalcharacteristicsofelectricalequipmentmeettherequirementsspecifiedinrelevanttechnicalregulations,ensuringnormaloperation.Transformers,instrumenttransformers,circuitbreakers,lightingarresters,andsimilarelectricalequipmentrequirebothinsulationtestingandcharacteristictesting.Insulators,powercables,andsimilarequipmenttypicallyundergoonlyinsulationtestingwithoutcharacteristictesting.Ⅰ.Classificationofhigh-voltagetestsbasedonfailurestrengthInsulationtestingcanbecategorizedintonon-destructivetestinganddestructivetestingbasedonthelevelofrisktotheinsulationofpowerequipment.Non-destructivetestingisperformedfirstandonlyuponpassing,destructivetestingcanbecarriedout.Incaseoffailure,insulationrestorationproceduressuchasdryingandsurfacecleaningarecarriedout.1.Non-destructivetestingNon-destructivetestingreferstothemeasurementofinsulationcharacteristicsofthetestspecimenusingtestvoltageslowerthantheratedvoltageoftheelectricalequipmenttodetermineifthereareanydefectswithintheinsulation.Thismethoddoesnotdamagetheinsulation.Commonnon-destructivetestingmethodsincludeinsulationresistanceandpolarizationindexmeasurement,dielectriclossmeasurement,directcurrentleakagecurrentmeasurement,andmostcharacteristictests.AsshowninFigure1-8.(a)Insulationresistancetester

(b)Dielectriclosstester

(c)DChighvoltagegenerationdeviceFigure1-82.DestructivetestingDestructivetestingreferstotheapplicationoftestvoltagesthataremuchhigherthanthenormaloperatingvoltageofelectricalequipmentforhighvoltagetesting,toassesstheabilityoftheelectricalequipmenttowithstandovervoltageandinsulationclearance.Iftheinsulationclearanceoftheelectricalequipmentdoesnotmeettherequirementsspecifiedbytechnicalstandards,theinsulationwillbreakdownduringthehigh-voltagetest,causingdamage.Therefore,thistestiscalleddestructivetesting.HighvoltagetestingincludesDCwithstandvoltagetest,ACwithstandvoltagetest,andimpulsewithstandvoltagetest.AsshowninFigure1-9.(a)PowerfrequencyACwithstandvoltageinstrument(b)ACresonantwithstandvoltageinstrumentFigure1-9Ⅱ.ClassificationofHighVoltageTestsbyLifeCycleHighvoltagetestscanbedividedintothreecategories:factorytests,commissioningtests,andpreventivetests.Factorytestsrefertoaseriesoftestsconductedbeforedeliveringthenewequipmenttothecustomer,toensurethattheproductperformancemeetsthedeliverystandards.Commissioningtestsareconductedjointlybythemanufacturerandtheownerbeforethenewequipmentisputintooperation.Preventivetestsrefertothetestscarriedoutaftertheowner’sequipmentisputintooperation.Thetestcontentofthesethreetypesissimilar,buttheyfollowdifferenttechnicalstandards.1.FactoryTestFactorytestsareconductedbypowerequipmentmanufacturerstoinspectandtesteachproductaccordingtorelevantstandardsandproducttechnicalconditions.AsshowninFigure1-10,1-11.Thepurposeofthetestsistoexaminethequalityofproductdesign,manufacturing,andprocessing,preventingdefectiveproductsfromleavingthefactory.Acomprehensiveproductqualificationtestreportwillbeissuedafterthefactorytest.Figure1-10

FactorywithstandvoltagetestforinstrumenttransformerFigure1-11

Factorywithstandvoltagetestfortransformer2.CommissioningTestCommissioningtestormajoroverhaultestreferstothetestconductedbytheinstallationdepartmentandmaintenancedepartmentonnewequipmentoroverhauledequipmentaccordingtorelevantstandards,producttechnicalconditions,orregulations.Thecommissioningtestisperformedbeforethenewequipmentisputintousetocheckforanydefectsordamagesduringtransportation.AsshowninFigure1-12.Aftermaintenance,theequipmentistestedtoensurethatthemaintenancequalitymeetstherequirements.Figure1-12

On-sitecommissioningtestfortransformer3.PreventiveTestPreventivetestreferstothetestconductedbytheoperatingdepartmentandtestingdepartmentduringacertainperiodaftertheequipmentisputintooperation.AsshowninFigure1-13.Thepu