外文资料翻译伺服阀试验台计算机辅助测试系统的研制.docx
- 文档编号:25471648
- 上传时间:2023-06-09
- 格式:DOCX
- 页数:16
- 大小:143.78KB
外文资料翻译伺服阀试验台计算机辅助测试系统的研制.docx
《外文资料翻译伺服阀试验台计算机辅助测试系统的研制.docx》由会员分享,可在线阅读,更多相关《外文资料翻译伺服阀试验台计算机辅助测试系统的研制.docx(16页珍藏版)》请在冰豆网上搜索。
外文资料翻译伺服阀试验台计算机辅助测试系统的研制
StudyonComputerAssistantTestSystemofServoValveTest-bed
Abstract:
Accordingtotheneedofthestaticanddynamiccharacteristicsofthetestonservovalve,firstlythisarticleintroducesthenecessarypartofthesystem-thepumpstation.Next,itdesignsthecorrespondinghydraulicandcomputer-aidedtestsystemandgiventhecompositionofsoftwareandhardwareofthetestsystemandthedesignprocessofsoftware.Intheend,weapplythedesignedsystemtoactualproductiontoprovethatitachievetherequirementsofthetestonservovalve.
Keywords:
servovalve,testrig,CAT,dynamicandstaticcharacteristics
1.Introduction
Electro-hydraulicservovalveisthefrequently-usedcontrolcomponentinmeasurementandcontrolsystem.Duetothewideuseofelectro-hydraulicservosysteminmetallurgy,engineeringmachinery,andchemicalindustry,alargenumberofservovalvesarealsobeappliedintheseindustries.Affectbythefactersofenvironmental,abrasion,agingandsoon,servovalvewillmalfunctioninevitablyandneedrepairsafterusingacertaintime.Aftermaintenanceandrepair,wemustdetecttheservovalvethroughsomecertaintestingmethodsofdynamicandstatictodecidewhetheritsvariouspropertiesmeetthestipulatedrequirementsornot.Thus,largeenterprisesestablishindependentservovalvetest-bedaccordingtotheownneeds.Whatisdescribedbelowisaservovalvetest-beddevelopedjointlybyourunitandauniversityandthetest-bedisbasedoncomputer-aidedtesting.
2.Hydraulicpumpstation
Hydraulicpumpstationalsoknownasthepumpstationisanindependenthydraulicdevice.Itoffersoilaccordingtotherequirementsgraduallyandcontrollsthedirection,pressureandflowrateofhydraulicoil,appliedtothemainframeandhydraulicdevicesseparabilityofhydraulicmachinery.Afterthepurchaseusersjustconnecthydraulicstationandhostofimplementingagencies(motoroilorfueltanks)withtubing,andhydraulicmachinerycanberealizethesemovementsandtheworkcycle.
Hydraulicpumpstationconsistsofpumpdevice,blockorvalve,tanks,acombinationofelectricalboxes.Thefunctionofeachcomponentsareasfollows:
(1)Pumpdeviceisequippedwithmotorsandpumps,isthesourceofpowerofthehydraulicstation.Itchangesmechanicalenergyintohydraulicoilpressureenergy.
(2)Integrationblockisassembledbyhydraulicvalveandchannelbody.Itcanadjustthedirection,pressureandflowofthehydraulicoil.
(3)Valveportfolioplatevalveisinstalledintheboardandchannelsconnectwitheachotheraftertheboardwitchisthesameasintegrationvalve.
(4)Tankplateisaweldingsemi-closedcontainer,andalsolocatedwithoilfilteringnetworkandairfiltersusedforoil,oilfiltersandcooling.
(5)Electricalboxeshavetwopatterns.Onedesignsexternalfuseterminalplate;Theotherinstallsafullrangeofelectricalcontrol.
Hydraulicstationprinciple:
motordrivenpumprotation,andpumpabsorbsoilfromtheoiltankandchangesmechanicalenergyintohydraulicpressureenergyofthestation.Hydraulicoilthroughmanifold(orvalvecombinations)realizestheadjustingofdirection,pressure,flow.Thenthroughexternalpipetothecylinderhydraulicmachineryormotor,soastorealizethechangingofthedirection,thesizeoftheforceandthevelocity,topromotethemachineryworkingofallkinds.
3.Hydraulictestingsystemandtestingmethods
Test-bedcancompletethetestonstaticanddynamiccharacteristicsofservovalve.Staticcharacteristicsofthetestincludescharacteristicsofunloadedflow,characteristicsofpressure-gain,characteristicsofflow-pressureandcharacteristicsofleakage;dynamiccharacteristicsaremainlythetestonfrequencycharacteristicsofservovalve.Theabovetestingresultsofcharacteristicsneedtobedrawnoutinthewayofgraph.Figure1isaschematicdiagramofhydraulictestsystem.
Accordingtothetestingtems,weinstallthevalvetobetestedonthestaticanddynamictestingboardrespectively.Whenweexecuteastatictest,weshouldclosetheswitchingvalve8,andopenthevalve6.Onthecontrary,turnonvalve8,andturndownvalve6whenwedoadynamictest.
3.1Testingmethodofcharacteristicsofunloadedflow
Operationsareasfollows,whenwetestthecharacteristicsofunloadedflow.First,closeswitchvalve18and7,andopenvalve17and9.WeshouldmakesurethepressuredifferencebetweenthetwooutputportsAandBoftheelectro-hydraulicservovalve△PL=0.Andtheninputtriangle-wavecurrentsignalwiththefrequencyof0.01Hzintothevalvebeingtested.Thesizeofthecurrentsignalvaryinaccordancewiththefollowingrule:
changesfrom0to+imax,thenfrom+imaxto0,thento+imax,andbackto0.Turbineflowmeter16detectstheflowintheprocessofthevaryingcurrentandinputthecomputerwiththemeasuredflowandcorrespondingcurrent.Thecomputercandrawthecurveoftheflowvaringwiththecurrent,namelythecurveoftheunloadedflowcharacteristics±q=f(±i)△pL=0.Andaccordingtothemeasureddata,wecancalculatevalveflow-gain,symmetry,zero-driftandhysteresisandotherimportantpropertiesofthevalve.
3.2Testmethodofload-flowcharacteristics
Theoperationsofthetestonload-flowcharacteristicsareasfollows:
First,openswitchvalve18and9,closethevalves17and7,makesuretheoilofportAandBflowsthroughtheone-wayvalve23andproportionalreliefvalve22.Proportionalreliefvalve(minimummoderatingpressure<0.5MPa)canchangetheloadpressureduringthetest,andtheturbineflowmeter16canmeasuretheflowunderavarietyofloadoperatingconditions.Tostartthetest,weshouldadjustthereliefvalve3,makesurethepressureofthesystemisthesameastheratedpressureoftheelectro-hydraulicservovalvetobetested.Theninputthevalvecoilbeingtestedwithatriangle-wavecurrentsignalof0.01Hz,andthencontroltheproportionalreliefvalve22tomaketheloadpressurechangegraduallyfromzerototheratedpressurebyacertainincrementandmeasuretheflowundereachincrementandinputintothecomputeratthesametime.Andthenchangetheamplitudeoftheinputcurrent(frequencyunchanged),repeattheaboveprocess,wecanmeasurecurvesofmoregroups.Thisisthecharacteristiccurveoftheloadflowofelectro-hydraulicservovalve±q=f(±△PL)i=Cont.
3.3Testmethodofpressurecharacteristics
Beforethetest,closedswitchvalve17,18and7andopenthevalve9,makesuretheoutputflowofthevalvetobetestediszero.Thenadjustthepressurereliefvalve3sothatthepressureofthesystemequalstotheratedpressureandreturnoilpressure(measuredbypressuresensor13).Theninputthevalvecoiltobetestedwithatriangularwavecurrentsignalof0.1Hz.Thecomputerreadsthevalueofpressuretransducer14and15,sowecandetectthepressuredifferenceofthetwooutportoftheservovalve.Changetheinputcurrentsignalamplitude,andwecanmeasurepressurevalueunderdifferentcurrentamplitudes.Pressure-gaincurvescanbesketchedout,accordingtothevalueofcurrentandpressuredifference±△PL=f(±i)q=0.
3.4Testingmethodofleakagefeatures
Closeswitchvalve17,18and9,andopenvalve7,thenadjustthereliefvalve3tomakethepressureofthesystemisthesameastheratedpressureofthevalvetobetested.Theninputthevalvecoilwithexcitingcurrentandmeasuretheflowbyflowtransducer5,andinputthecomputerwiththeleaksignalandratedexcitingcurrentsignalaftersampling.Leckagecurvescanbesketchedoutbythetestingsystemqr=f(±i).
3.5Testofdynamiccharacteristics
Accordingtotheinternationalstandard,testofdynamiccharacteristicsofcurrentservovalvemainlyreferstowidthofamplitudefrequencywhencharacteristiccurveofamplitudefrequencyis-3dBandphase-frequencywidthwhencharacteristiccurveofphase-frequencyis-90°.Weshoulduse10sinusoidalsignalsofdifferentfrequienciesforexcitingsignalsofthevalvecoiltobetested,thenmeasuretheoutputflowsignalinturnandfilteroutthesignalsdifferentwiththeexcitingsignaloftheflowsignalandserveitastheresponsesignalsoftheservovalvetobetested.Thetwosignalsareenteredintothecomputerbyturnsaftersampling,andepuatetheauto-spectralspectrumoftheexcitingsignalsGXX(f)andcross-powerspectrumofexcitingsignalsandrespondingsignalsGXY(f).BythismethodwecangetthefrequencyresponseH(f)=GXX(f)/GXY(f).
Whenwedothetestofthedynamiccharacteristics,closeswitchvalve6andopenvalve8.Anindependentsignalgeneratorproducesscaningsinusoidalsignal.Thesignalisenteredintotheservoamplifierafteramplificationanddrivethedynamiccylindertomove.Withthehelpofthespeedsensorinstalledonthedynamiccylinder,wecanequatetheoutputflowoftheservovalvebeingtested.Andtheshiftsensorinstalledontheothersidecanbeusedforpreventingthedynamiccylinderfromdeviatingfromthecentralposition.
4.Currentcircuitofthetestsystem
ThesignalsneedtobecollectedduringthestaticcharacteristicstestofthetestingsystemsignalsincludeCurrentsignalsoftheservovalvecoiltobetested,Pressureofinletoilport,PressuresignalofloadportAandB,Pressuresignalofleakingmouth,FlowsignalofloadportAandB,Flowsignalofleakingmouth.Thesignalsneedtobecollectedduringthedynamiccharacteristicstestincludecurrentsignalsofvalvecoiltobetested,Voltagesignaloutputedbyspeedsensor20.Controlsignalsoutputedbythetestingsystemincludesettingvalueofpressureoftheproportionalreliefvalve,Stimulatingsignals
- 配套讲稿:
如PPT文件的首页显示word图标,表示该PPT已包含配套word讲稿。双击word图标可打开word文档。
- 特殊限制:
部分文档作品中含有的国旗、国徽等图片,仅作为作品整体效果示例展示,禁止商用。设计者仅对作品中独创性部分享有著作权。
- 关 键 词:
- 外文 资料 翻译 伺服 试验台 计算机辅助测试 系统 研制