您好,欢迎访问三七文档
当前位置:首页 > 行业资料 > 能源与动力工程 > 21基于超声波的局部放电检测仪的研制
河北农业大学硕士学位论文基于超声波的局部放电检测仪的研制姓名:张德宁申请学位级别:硕士专业:农业电气化与自动化指导教师:张曙光2009-06-13STC89C52AD20RS485ADSTC89C52DevelopmentofanInstrumentinPartialdischargedetectorBasedonUltrasonicAuthor:ZhangDeningSupervisor:ZhangShuguangMajor:AgriculturalElectrificationandAutomationAbstractElectricalequipmentareimportantequipmentinpowersystemandpowertransmissionlineisthekeypartofthepowersystem.Ithasimportantsignificanttomakefaultdetectionanddiagnosisonelectricalequipmentandpowercables,detectthehiddenaccidentsofelectricalequipmentandpowercableintime,preventaccidents,andimprovethesafereliabilityofrunningelectricalequipment.Withthecontinuousimprovementofvoltageandtheeffectofthehigh-voltageandhighelectric-field,partialdischargewilloccurinsomeinsulationweaknessesoftheelectricalequipmentsandpowertransmissionline.Thereforeithasrealisticmeaningofdevelopmentapartialdischargedetectionequipmenttorealizetheon-linedetectionofelectricalequipmentandpowercables.Thisissueisraisedbasedonthisdemand.Inthisthesis,partialdischargedetectorbasedontheultrasoundisresearchedanddesignedsystematically.Ithasfeaturesofsmallsize,convenientusingandportable.Partialdischargedetector,whichusestheSTC89C52single-chipmicrocomputerasthecore,cancompletethedetectionofpartialdischarge,high-speeddataacquisitionandstorage,dischargealarming,dischargeintensityshowsandcommunicationwiththehostcomputer,etc.Inthehardwaredesign,theissueadoptstheideaofmodulardesign.Firstitchoosestheultrasonicsensorinaccordancewiththemechanismofpartialdischargeandtheultrasoniccharacteranditspropagationrules.Inordertoensurethesafetyandreliabilityofthedetector,itdesignsthephotoelectricisolationcircuitmodule,whichrealizesthestrongandweakelectricitypowerisolationwiththeopticaltransmissionmethod.Intheanalogsignalpre-processingunitandsamplingtriggercircuitdesignpart,itcompletesthedesignofamplifier,band-passfiltercircuit,samplingtriggercircuit.Inthehigh-speeddataacquisitionmodulespart,itmainlycompleteshigh-speeddatacollectionanditsstorage.Becausethespeedofsingle-chipcannotkeepupwiththesamplingrateofADC,itdesigns20-bitaddressgeneratorwiththehardwaretocompletethestorageofhigh-speeddata.Atthesametimeitcompletesthedesignofthedischargedisplaycircuit,alarmandresetcircuit.RS485interfacerealizesthecommunicationwiththehostcomputerandensuresthecommunicationdistanceandthenoiseimmunity.Inordertoanalyzetherelationshipbetweentheultrasonicsignalandthedischarge,eliminatenoiseinterferenceandaccuratelyextractthepartialdischargepulsesignal,itintroducestheextractionmethodofdischargesignalusingthewavelettransform.Finally,itmakesprospectsatthepartialdischargedetectorandproposessomemethodsofthinkingfromseveralaspectstodofurtherresearchandimprovementofthesystem.Thepartialdischargedetectorcanmakeon-linedetectionofpartialdischargeoftheelectricalequipmentandpowertransmissionlinesquicklyandeasily,collectandprocessthedataofthepartialdischargesignal.Thereforeitgreatlyreducestheoutagetimeandsavesreconditioningexpense,whichhasagoodapplicationprospects.Keywords:PartialDischargeUltrasonicSensorHigh-speedADConverterSTC89C52SerialCommunicationWaveletTransform11211.11.2JFY3[1]10kHz-1.2MHz50kHz50kHz400kHz72LABVIEW[2]NINILABVIEWEATechnologyUltraTEVDetector™2007UltraTEVPlus+™(MV)(HV)LCDUltraDish™TheUltraTEVPlus+™(MV)(HV)PD3[3]1.3[4][5][6]1.IECIEC76-31985GB1O94.3-85[7](RogowskiCoil)2.3.SF64SOF2SO2F2SF6SF64.MHz10MHz()[8]5.[9]-[10][11][12][13][14]PC[15][16][17]51280[18][19][20][21][22]3[23][24][25]1.46-[26][27]1)108EEsEcEc2)[28]3)1000R.Bartnikas[29]1)1-100ns2)3)[30][31][32]7[33][34][35]50kHz300kHz70kHz150kHz1.51.[36][37][38]2.[39]3.1.6STC89C52A/DRAM1.1ADSTC89C528ADSTC89C52RS485A/DRAMSTC89C52RS485PCA/D1.21.1Fig.1.1ThePrincipleFrameofHardware9ADAD1.2Fig.1.2FlowChartofSystem1.71.2.A/D3.AD4.LED5.1022.1162104Hz16Hz2104Hz2.10axxPPe−=20axxIIe−=xPxIx0P0IxαNp/m/2.22.1Fig.2.1ThePrincipleFrameofHardware112.2δfδ[40]1)80%2)3)4)[41][42]80kHz300kHz2.2Fig.2.2TheStructureofPiezoelectricUltrasonicSensor122.3[43]1)2)80kHz150kHz2.32.3Fig2.3ThePhysicalMapofUltrasonicSensor2.4[44]5m500KV()2.42.4Fig.2.4TheMapofSignalTransmission13[45]2.52.60.84µm1.31µm1.55µm2.6Fig.2.6TheSystemofOpticalFiberTransmission2.7LED2.7Fig.2.7TheSchematicofOpticalSignalSendingend2.5Fig.2.5TheSignalConverterSchematic142.82.8Fig.2.8TheSchematicofOpticalSignalReceivingend153A/D3.1AD3.1AD3.1.11.23111211nnnnFFFFGPGPGP−−=+++⋅⋅⋅⋅FnFn1Fn2GP3.1Fig.3.1AnalogSignalPre-processingUnitBlock162.[46]AD625INA111AD62522MHZ20V/µsAD8129270MHz103dB200MHz1060V/µs4.5nVHzU=0.1mv-0.5mvA/D2V8000100003.1.2(104)AD8129[47]AD8139[48]3.23.2AD8129AD8139Fig.3.2PinsofAD8129andAD8139AD812917200MHz1060V/µs@G=10CMRR94dBMinDCto100kHz80dBMin@2MHz1MΩ()4.5nVHz+4.5Vto±12.6VAD8139410MHz3dBBW(G=1)800V/µsCMRR80dBMin98dBcSFDR@1MHz85dBcSFDR@5MHz1MΩ()2.25nVHz2.1pAHz5Vto12VAD8129AD8129103.3()1OUTINFGOFFSETVVRRV=×++3.3AD8129Fig.3.3AD8129CircuitWiring18AD81394AD81393.43.4AD8139Fig.3.4TypicalCircuitofAD81393.1.31)mVAD80dB120dB2)3)4)195)6)60dBCMRR7)8)µVAD8129AD81393.53.5Fig.3.5Pre-amplifierCircuitADAD81393.6203.6Fig.3.6Output-amplifierCircuit42.5VVcmAD
本文标题:21基于超声波的局部放电检测仪的研制
链接地址:https://www.777doc.com/doc-5516984 .html