干式变压器英文试验大纲.docx

干式变压器英文试验大纲.docx

《干式变压器英文试验大纲.docx》由会员分享，可在线阅读，更多相关《干式变压器英文试验大纲.docx（11页珍藏版）》请在冰豆网上搜索。

干式变压器英文试验大纲

TestingItems、Methods、ProcedureandFormulas：

No.

TestingItems

TestingMethodsProcedureandFormulas

1

Voltageratio

measurementand

checkofvector

group

Adjustthetapchanger,andmeasuringvoltageratioerrorofeachtapofHV-LV.Thetestresultoferroratthenominaltapshouldbe≤±0.4%.ThevectorgroupshouldbeDyn11.Theformulaisasfollowing:

K=U1/U2

No.

TestingItems

TestingMethodsProcedureandFormulas

2

WindingD.C.

resistance

measurement

TomeasureD.C.resistanceofHVandLVwindingsatwindingendbyHS305,Thetestresultoferror:

phase<4%，line<2%.

K=（Rmax-Rmin.）/Rave.

Kistheunbalancedrateofthree-phaseDCresistance.

3

Measurementof

insulation

resistance

Transformerenclosureshouldbewellgrounded,thentomeasureinsulationresistance。

BymeasurementmeterZC11D-5,2500V.（HV:

>1000MΩ；LV:

>50MΩ）

Connectiondiagramofinsulationresistancemeasurementisasfollowing:

No.

TestingItems

TestingMethodsProcedureandFormulas

4

No.

A.C.voltage

withstandtest

TestingItems

Appliedvoltagewithstandtestuses50Hzsine-wavesingle-phaseA.C.voltage,testedwindingoftransformerisshortedandenergized,theothernon-testedwindingsareshortedgrounding,alsothecore,clampandtankaregrounded.Thistestisconsideredtobequalified,ifthereisnodischarge,breakdownandnosuddendecreaseoftestingvoltage.Thetestingvoltagesare:

HV&neutral-38kV60s,LV-3kV60s.（13.8KV/0.4KV）

HV&neutral-50kV60s,LV-3kV60s.（22KV/0.4KV）

TestingMethodsProcedureandFormulas

5

Inducewithstandvoltage

1、inducewithstandvoltage

Thewiringdiagramofinducewithstandvoltagetestisasfollowing:

L.Vacsurgemagnetism,HVsideisopen-circuit.

Wiringdiagramisfollowing:

H.Vinducewithstandvoltage:

（13.8kV×2；22kV×2）

Use50kVA、200Hzgeneratorsetthree-phaseoutputtoL.Vwindingoftestedtransformer.H.Vtappositionisat3step,Testlastsfor30s（Formula:

testtime=120*50/200=30s）.Thistestisconsideredtobequalifiedifthereisnofollowingsituation----current-increasing,difficultytoapplyvoltage,dischargeandbreakdownandotherabnormalsituation.

t=120*fr/f

t:

testtime

fr:

ratedfrequency

f:

testfrequency

No.

TestingItems

TestingMethodsProcedureandFormulas

6

Measurementof

no-loadlossand

no-loadcurrent

ThetestedtransformerisenergizedatLVsideby200kVAthreephasebooster.

Applythe400VvoltagefromL.Vsidetosurgemagnestim,MeasuretheI0andP0’.Aftercorrection,I0%andP0shouldmeettherequirementsoftechnicalspecification（13.8kV/0.4kV:

≤1.15kW;22kV/0.4kV:

≤1.35kW）.Duringthetest,HVsideisopen-circuit,neutralpointisearthed.

Po=Po’（1+d）

Po:

no-loadlossafterrevised.

Po’:

measuredno-loadloss

d=（Uavevalue-Uvirtualvalue）/Uavevalue

No.

TestingItems

TestingMethodsProcedureandFormulas

7

Measurementofshort-circuitimpedanceandon-loadloss

Accordingtorequirementsofthestandard,theloadlossandimpedanceatratedstep,shouldbemeasured.ThemeasurementshouldbeconductedbetweenHVandLVwindingswithHVenergizedandLVshort-circuit.Atratedstep,themeasurementvalueshouldbeaccordingtothetechnicalrequirement（13.8kV/0.4kV:

≤5.3kW;22kV/0.4kV:

≤5.41kW）.

Thepowersupplyforthistestisfrom200kVAgeneratorunitandtransmitstotestedtransformerinputtermina

P115℃=（Pk-Pr）/K+Pr*K

P115℃:

loadlossat115℃Pk:

measuredloadlossPr:

resistancelossK:

temperaturecoefficient

P115℃:

loadlossat115℃

Pk:

measuredloadloss

Pr:

resistanceloss

K:

temperaturecoefficient

No.

TestingItems

TestingMethodsProcedureandFormulas

8

No.

Measurementofpartialdischarge

TestingItems

Appliedvoltagephasetophaseis1.8Ur（Urisratedvoltage）,anddurationofvoltageapplicationis30s.Thenreducingthevoltagephasetophaseto1.3Uratholdingthesupply,lasts3min;Inthecourse,measuringpartialdischarge.

Ⅰ.Thetestcircuitforthreephasethransformerpartialdischargetest.

1----LVwinding2----HVwinding3----MeasurementintrumentS----Switch

Ⅱ.Themethodofapplingvoltageis9diagram.

9Diagramthemethodofapplingvoltageforthepartialdischarge.

TestingMethodsProcedureandFormulas

9

Measurementof

soundlevel

Duringtest,HVtapchangershouldbeatratedstep,ApplyingratedvoltageandratedfrequencyatLVside.Thesoundpressurelevelshouldbemeasuredatspecifiedlinewhichis1mfromreferenceradiatingsurface.Distancebetweentwoadjacentmeasuringpointsshouldbelessthan1m.

Beforeandaftersoundleveltest,backgroundsoundlevelalsoshouldbemeasured.Atlasttocorrectandcalculatethemeasureddataaccordingtostandards,theresultshouldmeetthecustomer’srequirement:

<47dB.

No.

TestingItems

TestingMethodsProcedureandFormulas

10

No.

Lightningimpulsetest

TestingItems

Thenegativefull-wavelightningimpulsetestsofHV,LVterminalareasfollowing:

Full-wave:

1.2±30%/50±20%μs,HV（peak）:

95kV（13.8KV/0.4KV）LV（peak）:

125kV（22KV/0.4KV）

Testprocedureisasfollowing:

Negativefull-waveimpulseatfirstreduced50%voltage;Negativefull-waveimpulseatthirdratedvoltage.Duringtest,there’snoabnormalsoundandthewaveshapewillnotbeabnormal,Thistestisconsideredtobequalified.

TestingMethodsProcedureandFormulas

11

Measurementof

temperaturerise

Temperaturetest（typetest）1.Technicaltestrequirement:

Temperatureriseofwinding:

100KTestsupply:

200KVA,50Hzthreephaseboober

Thewindingstemperature-risewerecalculatedbytheformula△θ’c=△θc[1+（△θe/△θc）1.25]0.8usingtheresultobtainedbytwoseparatetemperature-rise;thefirsttestwithonluno-loadloss,thesecondtestwithonlyloadloss.

Firsttest

Thehigh-voltagewindingofthetransformerwasop-circuitedandthelow-voltagewindingwassuppliedattheratedvoltage（400V）;thesesupplywereapplieduntilthesteady-stateconditionwasreached.

Then,resistanceofwindingsweremeasuredindirectcurrent（seegraphics）inordertodeterminetheirtemperature-risebyresistancevariationmethod.

Secondtest

Thelow-voltagewindingofthetransformerwasshort-circuitedandthehigh-voltagewindingwassuppliedatatastvoltagetoallowtheratedcurrent（13.8kV/0.4kV:

26.36A;22kV/0.4kV:

16.53A）topassthroughthehigh-voltagewinding;thesesupplywasapplieduntilthesteady-stateconditionwasreached.

Then,resistancesofwindingsweremeasuredindirectcurrentinordertodeterminetheirtemperature-rise△θcbyresistancevariationmethod.