Transcription
IEEE C57.12.00 –DGA / DRM ON TAP-CHANGERSFOR ROUTINE TESTSIEEE C57.12.00 – DGA / DRM on Tap Changers for Routine TestsIRainer FrotscherI03/11/2014Ipage 1 of 14
IEEE C57.12.00Scope of Tests defined in C57.12.00 (Tap Changers)Tap-ChangerCommentPositionsonly with first unit of newTable 18 (Static) Resistance Measurement Min / N / Max designSectionTestTable 18/Ratio Test8.3.1.AllVariable supply voltage, noloadTable 18/ Impedance voltage and8.3.2.load-loss testMin / N / Max Determination of uk, I08.3.2.1.Impedance testingMin / N / Max Which test setup ?Table 18No-load lossesat 1.0 and 1.1 x UNTable 18 Operational testNDetermination of no-loadlosses, I0Sequence Verification of mechanicalN–Min–Max–N and electrical functionIEEE C57.12.00 – DGA / DRM on Tap Changers for Routine TestsIRainer FrotscherI03/11/2014Ipage 2 of 14
IEEE C57.12.00Scope of Tests defined in C57.12.00 (Tap Changers)Tap-ChangerCommentPositionsonly with first unit of newTable 18 (Static) Resistance Measurement Min / N / Max design; method has beenvoted out (Fall 2013)SectionTestTable 18/Ratio Test8.3.1.AllVariable supply voltage, noloadTable 18/ Impedance voltage and8.3.2.load-loss testMin / N / Max Determination of uk, I08.3.2.1.Impedance testingMin / N / Max Which test setup ?Table 18No-load lossesat 1.0 and 1.1 x UNTable 18 Operational testNDetermination of no-loadlosses, I0Sequence Verification of mechanicalN–Min–Max–N and electrical functionIEEE C57.12.00 – DGA / DRM on Tap Changers for Routine TestsIRainer FrotscherI03/11/2014Ipage 3 of 14
IEEE C57.12.00Proposal for Additional TestsTransformer TestPass criteriaOne complete cycle of operationDe-energizedat 85% auxiliary supply voltage§ All tap changes shall be completedsuccessfully with no signs of abnormalmotor soundsEnergized§ Oil samples taken from the main tankbefore and after the test shall notNo-load condition at nominalindicate any dissolved gas increasesrated voltage (UN):§ Oil samples taken from the DiverterOne complete cycle of operation compartment before and after the testshall not indicate any dissolved gasincreases for tap changers of theTransformer in Load Lossvacuum switching typeconnection with minimum 80% § Voltage on the open side and no-loadof the maximum nameplatecurrent I0 show uniform patterncurrent IN in the regulatedthroughout the range (step curve)winding:§ Sound shall be uniform through allOne complete cycle of operation switching operations(introduced by T.Ansari, J.Foldi, Fall 2013)IEEE C57.12.00 – DGA / DRM on Tap Changers for Routine TestsIRainer FrotscherI03/11/2014Ipage 4 of 14
IEEE C57.12.00Proposal for Additional TestsTransformer TestPass criteriaOne complete cycle of operationDe-energizedat 85% auxiliary supply voltage§ All tap changes shall be completedsuccessfully with no signs of abnormalmotor soundsEnergized§ Oil samples taken from the main tankbefore and after the test shall notNo-load condition at nominalindicate any dissolved gas increasesrated voltage (UN):§ Oil samples taken from the DiverterOne complete cycle of operation compartment before and after the testshall not indicate any dissolved gasincreases for tap changers of theTransformer in Load Lossvacuum switching typeconnection with minimum 80% § Voltage on the open side and no-loadof the maximum nameplatecurrent I0 show uniform patterncurrent IN in the regulatedthroughout the range (step curve)winding:§ Sound shall be uniform through allOne complete cycle of operation switching operationsðThese tests should be introduced to PC57.12.00 (Table 18) or Section 8.3IEEE C57.12.00 – DGA / DRM on Tap Changers for Routine TestsIRainer FrotscherI03/11/2014Ipage 5 of 14
IEEE C57.12.00DGA on Tap Changers is not recommended for Routine Tests !– During the test, the oil heats up and produces dissolved gases,due to heating and/or catalytic effectsð Gas patterns before and after the test(s) cannot be the same !– DGA on Tap Changers is meaningful only for vacuum switching LTC typesð conventional arc-switching LTC types cannot be tested this wayð IEEE Standard is not generally applicable– Limit values for DGA are type-specificð Different data sets, one for each tap-changer type/family/brandð Potential source for misinterpretation !– Gas generation depends on application parametersð ”Normal” values vary with every applicationð Values which are normal for one type may indicate a fault for another typeIEEE C57.12.00 – DGA / DRM on Tap Changers for Routine TestsIRainer FrotscherI03/11/2014Ipage 6 of 14
IEEE C57.12.00Tap Changer Population – Big variety of types/modelsVacuumSwitching TechnologyArcArc-Breaking-in-OilSwitching TechnologyReinhausenOILTAP VIn-Tank TypeCompartment TypeReinhausenOILTAP MReinhausenVACUTAP VRTransitionResistorsTransitionReactanceABB UZReinhausen VACUTAP RMV-IIIEEE C57.12.00 – DGA / DRM on Tap Changers for Routine TestsIRainer FrotscherI03/11/2014Ipage 7 of 14
IEEE C57.12.00DGA on Tap ChangersWhen can it be helpful ?– Monitoring of LTC aging process– Detection of irregularities during LTC LifeWhat does it need ?– Trained personal for sampling, analysis, interpretation– Regular sampling ð building up a history / trend analysis– Initial sample after commissioning ð “Base line” data– Individual interpretation rules, depending on LTC model / brand / operational parameters(see PC57.139)– Guidance by LTC manufacturer is recommendedIEEE C57.12.00 – DGA / DRM on Tap Changers for Routine TestsIRainer FrotscherI03/11/2014Ipage 8 of 14
IEEE C57.12.00Winding Resistance MeasurementWhen can it be helpful ?– In field service– Finding contact problemsChange-over selector problemFine tap selector problemSource: Hydro Quebec, CIGRE 2006 Publication A2-102IEEE C57.12.00 – DGA / DRM on Tap Changers for Routine TestsIRainer FrotscherI03/11/2014Ipage 9 of 14
IEEE C57.12.00Dynamic Resistance Measurement (DRM)When can it be helpful ?– In field service / maintenance– Finding contact problems– Check of timing of tap selector AND diverter switchWhat does it need ?– DRM equipment (different suppliers)– Initial sample after commissioning ð Reference curve (individual fingerprint)– Trained personal for analysis and interpretation! Different LTC types ð Different signals !– Guidance by LTC manufacturer is recommendedIEEE C57.12.00 – DGA / DRM on Tap Changers for Routine TestsIRainer FrotscherI03/11/2014Ipage 10 of 14
IEEE C57.12.00Dynamic Resistance Measurement (DRM)Resistor type LTC (on-site measurement, fault-free)IEEE C57.12.00 – DGA / DRM on Tap Changers for Routine TestsIRainer FrotscherI03/11/2014Ipage 11 of 14
IEEE C57.12.00Dynamic Resistance Measurement (DRM)“Higher”“Lower”Diverter switch Resistor type LTCðHigh sampling rate shows switching sequence of Diverter SwitchSource: Raka Levi, “Dynamic Resistance Measurement applied to On-Load Tap Changers”IEEE C57.12.00 – DGA / DRM on Tap Changers for Routine TestsIRainer FrotscherI03/11/2014Ipage 12 of 14
IEEE C57.12.00Dynamic Resistance Measurement (DRM)Reactance type LTC (on-site measurement, fault-free)IEEE C57.12.00 – DGA / DRM on Tap Changers for Routine TestsIRainer FrotscherI03/11/2014Ipage 13 of 14
IEEE C57.12.00Dynamic Resistance Measurement (DRM)bridging to non-bridgingnon-bridging to bridgingbridging to non-bridgingStart motor driveReactance type LTC (on-site measurement, fault-free)IEEE C57.12.00 – DGA / DRM on Tap Changers for Routine TestsIRainer FrotscherI03/11/2014Ipage 14 of 14
IEEE C57.12.00 – DGA / DRM on Tap Changers for Routine Tests I Rainer Frotscher I 03/11/2014 I page 6 of 14 IEEE C57.12.00 DGA on Tap Changers is not recommended for Routine Tests ! – During the test, the oil heats up and produces dissolved gases, due to heating and/or catalytic effects ðGas patterns before and after the test(s) cannot be the same ! – DGA on Tap Changers is meaningful .File Size: 784KBPage Count: 14
