中文3925字畢業(yè)設(shè)計（論文）外文參考資料及譯文譯文題目：基于單片機(jī)的油浸式變壓器溫度監(jiān)測系統(tǒng)的設(shè)計學(xué)生姓名：學(xué)號：專業(yè)：通信工程所在學(xué)院：指導(dǎo)教師：職稱：2010年12月28日DesignofTemperatureMonitoringSystemforOil-immersedPowerRansformersBasedonMCUSuxiangQianHongshengHuDepartmentofMechanicalandElectrical,UniversityofZhejiangProvinceE-mail:jjqsx@126.comAbstract:¨CWiththeexpansionofelectriccapacityandlarge-scaleextensionofpowergrid,electricequipmentisplayingasignificantroleinmodernlife.Atpresent,thetechnologyofconditionmonitoringandfaultdiagnosingofpowertransformerhasbeenmadesomeimprovement,yetitsreal-timeperformanceandreliabilitystillcan'tmeettherequirementofsafeproduction.Duetodifferentthermaleffectsledbythenaturalorfactitiousfault,itstemperatureofoil-immersedpowertransformersiseasytochangeabnormally.Anon-linemeasuringandcontrollingsystembasedonMCUisdiscussedinthispaper.Inordertosatisfytherequirementofstatemonitoringandfaultdiagnosisofpowertransformeronreal-timeandreliability,akindofintelligenton-linemonitoringinstrumentisdesigned.Eachofitspartisexplainedinthispaper,includingtemperaturesignalcollectinganddataprocessingsystem.Thesimulationresultshowedthedesignedsystemwasgoodinitsreal-time,reliabilityandrunningcost.Therefore,thedesignedstatemonitoringsystemfortemperatureandfaultdiagnosisofpowertransformercanbewidelyusedinengineeringandisexpectedtobringabrightfuture.Keywords¨COil-immersedPowerTransformer,Temperature,Dataprocessing,MCUI.INTRODUCTIONsituation.Thereareseveralmethodstomeasurethehotspottemperature.AsimplemethodisthattheWiththecontinuousdevelopmentofeconomy,thetemperaturesensorcanbeusedtoconverttemperaturepowerindustryinourcountryhasenteredintoanewsignalintotheelectricsignalandthenthesamplingdatastageofdevelopment.Powertransformerhasbeenoneofcanbecollectedbytheinstrument.Inthispaper,athemostimportantequipmentsinelectricpowersystem.real-timetemperaturemonitoringsystemforAnditssafetyrunningplaysagreatimportantroleinoil-immersedpowertransformersisdesigned.Theordertoensuretheelectricpowersystem'sreliability.Atdesignedmonitoringsystemcaneffectivelymonitorpresent,theoilgasvalueandthesignaloflocaldischargesomekeyarea'stemperaturevariation:suchastheboxareoftenselectedasthemonitoringobjectsinthebody,thetransformerwinding,theironcore,andsoon,monitoringsystemofpowertransformer.Theanditplaysasignificantroleinsupervisorycontroltothecharacteristicgasesdissolvedinoilcanbemonitoredinoperationsituationoftransformers.realtime,whichcanhelpmonitoringpowertransformer'srunningstation.But,itcannotsatisfyinspection'srequirementofpowertransformer.Besides,thesignaloflocaldischargecanbeusedtojudgesomeA.Overallplanofthedevelopedsystemfault'slocation,yetitsreal-timeperformanceisweak.Basedonthetemperaturefieldinformationofpowertransformers,thisresearchsupportedbyNSFCexploresanewconditionmonitoringandfaultdiagnosiswayforit.Anon-linetemperaturemonitoringsystemofoil-immersedpowertransformersbasedonMCUisdesignedinthispaper.Itsvariationoftemperatureinpowertransformeroftenkeepsafixedorderlinesswhenitisrunningnormally.Inmostsituations,itsvariationoftemperatureinpowertransformerhasacloserelationshipwithdifferentfaulttypes.Theinteriorfaultpatternsofoil-immersedtransformerarereferringtomechanism,heatingandelectricity,andmainlythelattertwo.Themachinerymalfunctionoftenispresentedintheformofthermalorelectricity.Accordingtotheinvestigationresultpresentedinthetable1,themalfunctionwaysfortherunningoil-immersedtransformersincludemainlytheoverheatingmalfunctionanddischargingmalfunctionofhighenergy.Thetemperaturerisingwilloccurinsomelocationswhenoverheatmalfunctionorhighenergydischargingmalfunctionoccurs.Furthermore,anobviouemperaturerisingwilloccurforsomepowertransformersbeforethemalfunctionareformed.Onconditionthatthereal-timemonitoringtothecorrectareascanberealized,apreventivemaintenancewouldalterthepresentmaintenanceandinspectionmode,andbeabletoreducetheMaintenanceCost.Therefore,itisveryimportanttokeepthepowertransformersinthebestsituation.Thereareseveralmethodstomeasurethehotspottemperature.Asimplemethodisthatthetemperaturesensorcanbeusedtoconverttemperaturesignalintotheelectricsignalandthenthesamplingdatacanbecollectedbytheinstrument.Inthispaper,areal-timetemperaturemonitoringsystemforoil-immersedpowertransformersisdesigned.Thedesignedmonitoringsystemcaneffectivelymonitorsomekeyarea'stemperaturevariation:suchastheboxbody,thetransformerwinding,theironcore,andsoonanditplaysasignificantroleinsupervisorycontroltotheoperationsituationoftransformers.II.HARDWAREDESIGNA.OverallplanofthedevelopedsystemItsfunctionofthedesignedhardwaremainlyincludestwoparts:datacollectingandtransferringBesides,thecontrollingcircuitcanbefurtherexpandedinordertocontrolsomeprotectorsbyusingtherelayswitch.Thedesignedprinciplesareexplainedasfollows:themonitoredphysicalquantitiesmustbefirstlysampledbythetemperaturesensor(PT100,electricthermo-couple,opticalfibersensoretc)andconvertedintothevoltagesignal,thenthesampledvoltagesignalscanbeadjustedbyregulativesignalcircuittothestandardsignal'srange,andareconvertedintodigitalsignal,aftergenerallinetransmissiontoMCUforstorageandprocessing,simulation/digitalconvertingratecanbecontrolledbyMCU.ThetakeoverdataqueenmayexisttemporarilyintheextendedRAM,ortransfertothecomputerbyUSB.Atthesametime,MCUconnectkeyboardandLCDforthepurposeofman-machineexchange[2].ThesystematicblockdiagramofhardwaresystemisshowedinFig.1.1)ChipsSelection:A/Dmoduleselection--MAX125Inordertoavoidadditionalphasedifferenceintheprocessofthedatacollecting,thesynchronismcollectingtechnologymustbeguaranteedfordifferentsignals.AsynchronizedatasamplingchipMAX125theMAXIMcompanyproducesisselectedandusedinthedesignedcircuit.MAX125is2?á4channel,high-speedand14digitdatacollectchip[3].USBinterfaceschipchoose--PDIUSBD12PDIUSBD12hereinafterreferredto"D12",supportingmultiplexing,non-multiplexingandDMAtransfer,isonekindofparallelinterfacechipdesignedbyPhilipscompany.ItfullyconformstotheUSBspecificationRev.1.1(basicspeed).Itisalsodesignedtobecompliantwithdifferenttypesoftransmission.ThedatacollectingpartsblockdiagramsofhardwaresystemseeFig.2.Fig.2CireuitblockdiagramofdataacquisitionFig.1BlockDiagramofhardwarecircuitsystemFig.2CireuitblockdiagramofdataacquisitionFig.1BlockDiagramofhardwarecircuitsystemFig.4ResistingalissingfilterFig.3SchematicdiagramofisclationampliicationcireuitFig.4ResistingalissingfilterFig.3SchematicdiagramofisclationampliicationcireuitB.DesignoftheSignalConditioningCircuitTheSignalConditioningCircuitiscomposedofsensor,signalamplificationandattenuationcircuit,isolationcircuit,wavefilteringcircuit,sampleholdingcircuit,etc.DuetoMAX125ADchipwithmultiplexerandSample-HoldCircuititself,SignalConditioningCircuitismadeupwiththermocouple,isolatingamplifiercircuitandanti-aliasingfilter.ThethermocoupleproducedbyAnhuiTiankangincorporatedcompany,ModelfortheWRC,IndexingforT,isaspecialoneforpowerstationapplication.Itsoutputtingvoltagerangeis?à5Vanditsmeasuringtemprangesfrom50to200.TheAD204isageneral-purposeusedindustrystandardisolationamplifier,withtwo-port,transformer-coupledisolation.Besides,itcanofferacompletelyisolationfunction,includingsignalandpowerisolation,yetitspackageiseasilycompated.Figure3isitsprincipleofthedesignedisolatedenlargecircuit.Intheactualrunningscene,thecircuitmustdrawnearthesignalsourceinordertoavoidthesignalaffectedbyambientnoiseandenhancethesignal-to-noiseratio.Wavefilteringcircuitadoptresistaliasingfilter,thecircuitdesignedisshowsasFigure4.Duetotheconditionalityofchoosingcapacitance,thenumericalvalueofcapacitanceistakenintoaccountfirstly.ThefilterdesigningsoftwareFilterLabofMicrochipcorp[6]isusedinthispaper.Usingthesoftware,thescopefrequencyresponseandphasefrequencyresponsecanbeexpedientlyfound,andthedesignparametercanbeeasilyadjusted.C.DesignofdatacollectingInordertoconstructan8-channel-synchronismA/Dconvert,therearetwopiecesofMAX125inthedesigneddatacollectingcircuit.Thelow8outputdigitalfromMAX125throughAD0~AD7arerespectivelyjoinedwithP0.0~P0.7ofW77E58.AndhighsixfiguresamountA8~A13isrespectivelylinkedwithP2.0~P2.5ofW77E58.ALEpinofW77E58holdsCLKofMAX125,andP3.3pin,P3.6pinandP3.7pinperformacontrolfunctiononMAX125component.Fig.6USBinterfacescireuitFig.5MCUcontrolcireuitFig.6USBinterfacescireuitFig.5MCUcontrolcireuitDesignofMCUcontrolcircuitThecontrolsystembasedonMCUisshownasFig.6.BecausetheUSBagreementframeiscomparativelybig,W77E58chipwith32KBFlashEPROMisselectedasMCU.W77E58isthatoneis8bit,especiallyspeedyandmuchbetterperformanceCPU.What'smore,itisabletopayavisittolowspeedorfleetnessoutsideRAM.Comparedwithotherprocessingchipssuchas8052processor,W77E58canworkwithhigherspeedevenifunderthesameclockfrequencyandworkunderlowclockfrequency.ItspowersourceconsumptionisgreatlyreducedunderthesameinstructionhandlingcapacitysincetheentirestaticstateCMOSdesignisadopted.TherearefourI/Oportswith8bitandanadditional4I/OportinW77E58.ThesecharacteristicsW77E58possesscanmakeitworkbetter,suchasdirectlytransferringdatawithMAX125usingdifferentspeed,deliveringdatabetweenthecomputerandMCUbasedonUSBusinghighspeed,etc.AnditisveryusefultoexpandtheoutsidememoryforsystemusingotherI/Oports.TherearetwoconnectiontypesbetweenW77E58andD12,includingindependentaddressdatabusmodeandmultiplexaddressdatabusmode.TheanaloguesignalcanbeconvertedintodigitalsignalbyA/Dsamplingcircuit,andthentheconverteddigitalsignalbetransferredtoPCbyUSBinterfacetransference.E.USBinterfacecircuitdesigtUSBinterfacecircuitisshownasFig.5.WhentheperipheralequipmentsareconnectedwithconcentratorbyD12,concentratorcanchecktheconnectionstateofperipheralequipmentandreportittothehostcomputer.Oncetheequipmentconnectioninformationisfound,thehostcomputerisaskedtosendaseriesofrequesttoconcentrator,andthenacommunicatingchannelbetweenhostcomputerandequipmentwouldbeestablishedbyconcentrator.Further,thehostcomputerbeginstolistequipments,andsetsuptheperipheralequipmentsaftertheyaresuccessfullylistedandthecorrelativeallocationinformationisacquiredbythehostcomputer.Theperipheralequipmentrecognizedbyhostcomputercanbearrangedtocommunicatewithit.III.SOFTWAREDESIGNA.DatacollectingprogrammingAccordingtothecontrollingtimesequenceofMAX125,theflowofdatacollectingtaskisshownasFig.7.B.USBdrivedesign1)Firmwareprogramming:TherearegenerallythreepartsbetweenUSBandMCUfirmware:(a)InitializeMCUandallperipherycircuit(includePDIUSBD12);(b)Maincyclepart:thispartistobeinterrupted;(c)Interruptserviceroutine,cancarryoutimmediately.ThecommunicationbetweenMCUandPDIUSBD12ismainlyreferencedtosendordersanddatatoPDIUSBD12byMCU.TherearethreekindsofordercharactersforPDIUSBD12,includingtheinitializationordercharacter,thedatastreamordercharacterandtheuniversalordercharacter.PDIUSBD12hasshownthevariousimperativecodeandaddress.TheMCUfirstlysendsordersintotheorderaddressofPDIUSBD12,resendorreaddifferentdataaccordingtodifferentimperativecall.Therefore,itisconveniencetoconvertperkindorderintofunctionandusefunctiontofinisheachorderbydirectlycallingthesefunctions.2)Driveprogramming:Although,therearemanystandardinterfacefunctionsprovidedinthesystem,driverprogrammingisstilloneofthemostdifficulttasksforUSBexploitation.WindowsDDKisoftenadoptedtorealizedriveprogramming.Atpresent,thirdpartysoftwarefirmshaveprovidedalotofgeneratingtoolsfordriveprogramming,suchasdriverworksofCompuware,DriverWizardwaitsofBlueWaters.ThesetoolsareabletoproduceahighqualityUSBdrivingprogramwithinseveralminutes.WhencheckingUSBequipment,UsbViewprogramcanbeusedtodetectequipmentwhetherornottobeenumeratedandallocatedbyWindows.Ifsuccessful,thedevicedescription,allocationdescriptionandendpointdescriptionmaybecheckwhetherornotcorrectly.Andagenerally-purposeprogramcanbemadebyDriverWizard.OnceWindowsarealsoexploitedanddebuggedwiththedebuggingUSBdevicesendscluestoinstallthedrivingprogram,thedrivingprogramproducedbyDriverWizardwouldbeselected.Infact,itisonlyanapplicationprogramproducedbyDriverWizardforWindowscontrollingtable.ItisabletocalltheuniversalUSBdriveprograminstalledinsystemwhenassemblingDriverWizardforaspecifictask.Itsworkingconditionofdevices,includingtransferringdatawhetherornotcorrectlyandcontrollingthetransmissionspeed,canbemeasuredbythedriveprogram.Ifitcannotmeettheapplicationdemands,anewdriveprogramcanbewritedown.Besides,thesoftwareforhostcomputer.IV.APPLICATIONRESEARCHOFTEMPERATUREMONITORINGSYSTEMFORPOWERTRANSFORMERSBecauseofthelimitoftestingcondition,thedesignedtemperaturemonitoringsystemfortransformershasnowaytobecheckedundernormalworkingconditionsfortransformer.Yet,asuitoftemperaturerisingsimulationexperimentplatformfortransformerisdesignedanddevelopedforthisresearchpurpose.Intheexperiment,transformeroilisstoriedintheinneroftheactualtransformerboxbody,aheaterwasusedtosimulatewinding'stemperaturerisingvariation,andelectricthermo-coupleisusedtomeasurewinding'stemperaturerisingvalue.Besides,PT100measuresdifferentlocation'stemperaturerisingvalue,theinfraredthermometermeasuresthetemperaturerisingofboxbody,andthemercurialthermometermeasuresthetopoiltemperature.Theoutputwiresofsensorareconnectedwiththemonitoringsystem,andthedatacanbeshownonPCscreenintherealtime.ThelineconnectionandtheexperimentresultarerespectivelyshowedasFig.8andFig.9.Intheexperiment,thethermometer,infraredthermometer,electricthermo-coupleandthermalresistancearealladopted,comparedandverified.Forexample,athermometerwasmadeuseoftotestthetopoiltemperature,andelectricthermo-coupleforthewindingtemperaturerising,andthermalresistanceandinfraredradiationthermometerfortheoiltemperatureatdifferentlocations.ItcanbeseenfromFig.8andFig.9thatthehighesttemperatureisalwaysonthe"winding",thetemperatureofmildtransformeroilandboxbodyreflectsgradchangeandhasastep-by-steprise,andthetemperaturechangeoftransformerbottomoiliscomparativelyslow.TheexperimentresultisbasicallyagreedwiththesimulationcalculationvalueinANSYS.Accordingtotheexperimentalresults,therearesomecharactersforthedesignedtemperaturemonitoringsystemofpowertransformers:(a)Real-timeacquisition,realtimetransferringbyUSBbus.ItcanalsotransferthedatatoPCbyUSBafterdatacollecting;(b)ThereareakeyboardtocontrolitsworkingandLCDtodisplaydata.Besides,itcanworkundertheconditionofisolatedfromthePC;(c)Theparallelcollectingmodecanbesetandadoptedrandomlyfor1~8channel;(d)Increasingthedifferentcircuitstoprovidethevariousinterfaceslinkingforthevariousdifferenttypeofsensor.(e.g.PT100,electricthermo-couple,theopticalfibertemperaturesensorandsoon);(e)Measuringrange:-50~+200;(f)Workinginoilforalongperiodoftime.V.CONCLUSIONSInthispaper,itsmechanismofthetemperaturemonitoringtechnologyfortransformersisintroducedfirstly.Classificationandanalysisofdifferenttypesofmalfunctionfortransformersisprocessed.Thehardwarecircuitofmonitoringsystemhasbeenexplored,includingregulativesignalcircuit,wavefilteringcircuit,datacollectingcircuit,MCUcontrollingcircuit,USBinterfacecircuit,etc.Besides,thesoftwareflowofdatacollectingandtheUSBdriverprogramarealsoexploited.Thedesignedmonitoringsystemhasbeenappliedintothetemperaturerisingsimulationexperimentforpowertransformers.AndtheexperimentresultisbasicallyagreedwiththenumericalsimulationresultsusingANSYSsoftware.ACKNOWLEDGMENTTheresearchworkissupportedbythenationalnaturalsciencefoundationofChina(50575095).REFERENCES:[1]SunCaixin.On-lineGasinoilmonitoringandfaultdiagnosistechnologyofelectricequipment[M].Beijing:SciencePress,2003,5866[2]MAXIMcorp.MAXIMproductdatacorpora[CD].2004[3]ZhouLigong.PDIUSBD12USBfirmwareprogramminganddriverdesign[M].Beiing:Beijinguniversityofaviationandspaceflightpress,2003,11112[4]AD2O2204,Databook,AnalogDevices[CD].2001[5]Afilterprimer,MaximApplicationNotes[CD].2001[6]Wright.Nick,Judd.Bob.UsingUSBasadataacquisitioninterface[J].EvaluationEngineering,v43,n6,2004.6,2026[7]WangZhiqiang,SunShuying,SunShiyu.ResearchofdevelopmenttechnologyofUSBapparatusdrivers[J].Control&Automation,2005.9,2327

基于單片機(jī)的油浸式變壓器溫度監(jiān)測系統(tǒng)的設(shè)計錢蘇香，胡宏升（中國，大學(xué)浙江省嘉興市，機(jī)電系）電子郵箱：jjqsx@126.com摘要-針對變壓器檢測系統(tǒng)在實時性，可靠性方面的要求以及油浸式變壓器發(fā)生故障時會產(chǎn)生不同的熱效應(yīng)，從而產(chǎn)生相應(yīng)位置的異常溫升的問題，討論了基于嵌入式技術(shù)的大型變壓器溫度檢測和故障診斷系統(tǒng)，詳細(xì)的介紹了基于單片機(jī)控制的油浸式變壓器溫度采集電路的硬件電路設(shè)計。實踐結(jié)果證明，該系統(tǒng)具有實時性強(qiáng)，可靠性高，運行成本低等優(yōu)點。對大型油浸式變壓器運行狀態(tài)的實時溫度檢測和故障診斷而言，具有較廣闊的應(yīng)用前景。關(guān)鍵詞-油浸式電力變壓器，溫度，數(shù)據(jù)處理，單片機(jī)一導(dǎo)言隨著經(jīng)濟(jì)的不斷發(fā)展，電力行業(yè)在我們國家已經(jīng)進(jìn)入了一個新的發(fā)展階段。大型變壓器在輸變電系統(tǒng)中的作用極其重要。其長期，安全，可靠，高效運行的重要性不言而喻。在目前，石油天然氣價值和局部放電信號通常選擇作為電力變壓器監(jiān)測系統(tǒng)的監(jiān)測對象。運用油中溶解氣體的特性，可監(jiān)測實時性，它可以幫助監(jiān)察權(quán)變壓器的運行站。但是，它不能滿足檢查電力變壓器的要求。此外，局部放電信號，可以用來判斷一些斷層的位置，但它的實時性較弱?；跍囟葓鲂畔㈦娏ψ儔浩鳎狙芯坑蓢易匀豢茖W(xué)基金支持并探索了一種新的狀態(tài)監(jiān)測和故障診斷方式。一個在線溫度監(jiān)測系統(tǒng)基于單片機(jī)的油浸式電力變壓器設(shè)計誕生了。電力變壓器溫度變化經(jīng)常保持在一個固定的秩序使它運行正常。在大多數(shù)情況下，其電力變壓器溫度變化有不同的故障類型。這些模式的石油內(nèi)部故障油浸式變壓器指的是機(jī)熱，加熱和電力，主要是后兩種。機(jī)械故障往往呈現(xiàn)為熱電力形式。根據(jù)調(diào)查結(jié)果列于圖1，該油浸式變壓器運行的故障主要包括過熱故障和放電高能量的故障。溫度升高將發(fā)生在一些地點，此時過熱故障或高能量放電故障發(fā)生。此外，一個明顯的溫度升高會在一些力量變壓器發(fā)生故障前形成。理論上實時監(jiān)控到正確的地區(qū)可以實現(xiàn)，將預(yù)防性維護(hù)并改變目前的維護(hù)和檢查方式，能夠減少維護(hù)成本。因此，最重要的是保持在最佳的電力變壓器狀態(tài)。有幾種方法來衡量熱點溫度。一個簡單的方法是，溫度傳感器可用于把溫度信號轉(zhuǎn)換成電信號，然后收集采樣數(shù)據(jù)。本文就是油浸式電力變壓器實時溫度監(jiān)控系統(tǒng)的設(shè)計。該監(jiān)控系統(tǒng)設(shè)計的可以有效地監(jiān)測一些重點地區(qū)的溫度變化：如盒體，變壓器繞組，鐵心等等，它扮演了一個重要的控制作用，監(jiān)督變壓器的運行情況。二硬件設(shè)計本系統(tǒng)的硬件部分主要完成數(shù)據(jù)的采集和傳輸功能，還能通過控制電路實現(xiàn)一些擴(kuò)展的控制功能，如采用繼電器開關(guān)來控制一些裝置的啟停等。硬件系統(tǒng)的設(shè)計原理如下：首先外來信號經(jīng)溫度傳感器（PT100的，電熱電偶，光纖傳感器等）轉(zhuǎn)換為電壓信號，經(jīng)信號調(diào)整電路調(diào)整為標(biāo)準(zhǔn)信號范圍，并轉(zhuǎn)換成數(shù)字信號。經(jīng)總線傳輸至單片機(jī)控制處理。此次收集的數(shù)據(jù)可暫時存在擴(kuò)展的RAM中，或移交給計算機(jī)的USB接口。與此同時，單片機(jī)就可以用鍵盤和LCD的機(jī)用途的人造交換[2]。該系統(tǒng)的硬件系統(tǒng)框圖顯示在圖1。1）芯片的選擇

：A/D轉(zhuǎn)換模塊的選擇-MAX125In為了避免額外的數(shù)據(jù)處理階段的差異收集，必須使同步采集技術(shù)應(yīng)保證提供不同的信號。同步數(shù)據(jù)采樣芯片選擇美心公司生產(chǎn)的MAX125的并在電路設(shè)計中使用。MAX125是2×4通道，高速數(shù)據(jù)采集，14位的芯片[3]。USB接口芯片選擇-DIUSBD12，PDIUSBD12的簡稱為“D12的”?，支持復(fù)用，非多路復(fù)用和DMA轉(zhuǎn)讓，是一種實物并行接口芯片，是由設(shè)計飛利浦公司生產(chǎn)。它完全符合USB規(guī)范修訂版1.1（基本速度）。它的另一個目的是要符合不同類型的傳輸。塊數(shù)據(jù)采集部分的硬件圖系統(tǒng)見圖2。B.設(shè)計的信號調(diào)理電路是由傳感器，信號放大，衰減電路，隔離電路，濾波電路，保持電路等組成，由于AD芯片MAX125與多工器和采樣保持電路本身，信號調(diào)節(jié)電路與熱偶電路，隔離放大器電路和抗混疊濾波器電路。熱電偶是由安徽天康注冊公司生產(chǎn)的。T標(biāo)引，是一種特殊的一電廠中的應(yīng)用。它的輸出電壓范圍為±5V和其測量溫度范圍從50到200度。圖1硬件電路框圖系統(tǒng)圖2電路框圖的數(shù)據(jù)采集圖3隔離放大電路示意圖圖4抗混疊濾波器示意圖該AD204是一般用途的行業(yè)標(biāo)準(zhǔn)隔離放大器，與兩端口，耦合變壓器隔離。此外，它可以提供一種完全隔離功能，包括信號和電源隔離，但其包裝很容易兼容。圖3是按原理設(shè)計的隔離放大電路圖。在現(xiàn)時的實際運行，該電路必須干擾附近的信號源，為了避免信號的影響，可以通過環(huán)境噪聲，提高信號的信噪比。濾波采用抗混疊濾波器電路，電路設(shè)計為圖4。電容的選擇要求，數(shù)值電容值應(yīng)優(yōu)先考慮。該過濾器的設(shè)計軟件是由FilterLabMicrochip公司設(shè)計。[6]使用該軟件，范圍頻率響應(yīng)和相位頻率響應(yīng)可方便地找到，設(shè)計參數(shù)可容易調(diào)整。C.為了構(gòu)建一個8通道同步A/D轉(zhuǎn)換，電路中的MAX125應(yīng)設(shè)計為數(shù)據(jù)采集電路。數(shù)字輸出的低8位和MAX125AD0AD7級，分別通過聯(lián)同P0.0的W77E58的P0.7輸出的。高六位A8的輸出分別為A13號與P2.0的P2.5相連的W77E58的輸出。W77E58中持有的ALE引腳是時鐘MAX125，與P3.3引腳，引腳P3.6和P3.7引腳一同運行。D.單片機(jī)控制電路設(shè)計的控制系統(tǒng)為圖6。因為USB協(xié)議框架比較大，W77E58中有32KB閃存芯片EPROM的被選擇為微控制器。W77E58的一個是8位，特別快速而且有更好的表現(xiàn)性能。更何況，它能夠有機(jī)會參與或低速傳送到機(jī)內(nèi)的RAM。相比其他處理如8052處理器芯片，W77E58可以使用更高的速度，即使在相同的時鐘頻率和較低的時鐘頻率下工作。其動力源消耗在同一靜態(tài)指令處理能力大大減少，因為整個系統(tǒng)都采用CMOS設(shè)計。有四個8位得I