电气工程专业英语翻译.docx
- 文档编号:2996929
- 上传时间:2022-11-17
- 格式:DOCX
- 页数:7
- 大小:37.81KB
电气工程专业英语翻译.docx
《电气工程专业英语翻译.docx》由会员分享,可在线阅读,更多相关《电气工程专业英语翻译.docx(7页珍藏版)》请在冰豆网上搜索。
电气工程专业英语翻译
Step7.Tryanoptimaldesign.Ifthetrial-and-errorcompensatorsdonotgiveentirelysatisfactoryperformance,consideradesignbasedonoptimalcontrol.Thesymmetricrootlocuswillshowpossiblerootlocationsfromwhichtoselectlocationsforthecontrolpolesthatmeettheresponsespecifications;youcanselectlocationsfortheestimatorpolesthatrepresentacompromisebetweensensorandprocessnoise.Plotthecorrespondinganditsrobustnesstoparameterchanges.Youcanmodifythepolelocationsuntilabestcompromiseresults.Returningtothesymmetricrootlocuswithdifferentcostmeasuresisoftenapartofthisstep.orcomputationsviathedirectfunctionsIqrandIqecanbeused.Anothervariationonoptimalcontrolislaproposeafindstructurecontrollerwithunknownparameters.formulateaperformancecostfunction.anduseparameteroptimizationtofindagoodsetofparametervalues.
Comparetheoptimaldesignyieldingthemostsatisfactoryfrequencyresponsewiththetransform-methoddesignyouderivedinStep5.SelectthebetterofthetwobeforeproceedingtoStep8.
Step8Buildacomputermodel,andcompute(simulate)theperformanceofthedesign.Afterreachingthebestcompromiseamongprocessmodification,actuatorandsensorselection,andcontrollerdesignchoice,runacomputer,runacomputermodelofthesystem.Thismodelshouldincludeimportantnonlinearitiessuchasactuatorsaturation,realisticnoisesources,andparametervariationsyouexpecttofindduringoperationofthesystem.ThesimulationwilloftenidentifysensitivitiesthatmayleadtogoingbacktoStep5orevenStep2.Designiterationsshouldcontinueuntilthesimulationconfirmsacceptablestabilityandrobustness.Aspartofthissimulationyoucanoftenincludeparameteroptimization,inwhichthecomputertunesthefreeparametersfarbestforbestperformance.Intheearlystagesofdesign,themodelyousimulatewillberelativelysimple;asthedesignprogresses,youwillstudymorecompleteanddetailedmodels.Atthisstepitisalsopossibletocomputeadigitalequivalentoftheanalogcontroller.Somerefinementofthecontrollerparametersmayberequiredtoaccountfortheeffectsofdigitization.Thisallowsthefinaldesigntobeimplementedwithdigitalprocessorlogic.
Iftheresultsofthesimulationprovethedesignsatisfactory,gotoStep9;otherwisereturntoStep1.
Step9.Buildaprototype.Asthefinaltestbeforeproduction,itiscommontobuildandtestaprototype-Atthispointyouverifythequalityofthemodel,discoverunsuspectedvibrationandothermodes,andconsiderwaystoimprovethedesign.Implementthecontrollerusinganembeddedsoftware/hardware.Tunethecontrollerifnecessary.Afterthesetests,youmaywanttoreconsiderthesensor,actuator,andprocessandreturntoStep1-unlesstime,money,orideashaverunout.
Thisoutlineisanapproximationofgoodpractice;otherengineerswillhavevariationsonthesethemes.Insomecasesyoumaywishtocarryouttheminadifferentorder,toomitastep,ortoaddone.Thestagesofsimulationprototypeconstructionvarywidely,dependingonthenatureofthesystem.Forsystemswhereaprototypeisdifficulttotestandrework(forexample,asatellite)orwhereafailureisdangerous(forexample,activestabilizationofahigh-speedcentrifugeorlandingahumanonthemoon),mostofthedesignverificationisdonethroughsimulationofsomesort.Itmaytaketheformofadigitalnumericalsimulation,alaboratory-scalemodel,orafull-sizelaboratorymodelwithasimulated(forexample,feedbackcontrolforanautomotivefuelthesimulationstepisoftenskippedentirety;designverificationandrefinementareaccomplishedbyworkingwithprototype.
Oneoftheissuesraisedabove(Step6)wastheimportantconsiderationforchangingtheplantitself.Inmanycases,properplantmodificationscanprovideadditionaldampingorincreaseinstiffness,changeinmodeshapes,reductionofsystemresponsetodisturbances,reductionofCoulombfriction,andchangeinthermalcapacityorconductivity,andsoon.Itisworthelaboratingonthisbywayofspecificexamplesfromtheauthors'experiences.Inasemiconductorprocessingexample,theedgeringholdingthewaferwasidentifiedasalimitingfactorinclosed-loopcontrol.Modifyingthethicknessoftheedgeringandusingadifferentcoatingmaterialreducedtheheatlossesand,togetherwithrelocatingoneofthetemperaturesensorsclosertotheedgering.resultedinsignificantimprovementincontrolperformance.Inanotherapplication,thinfilmprocessing,simplychangetheorderofthetwoincomingflowsresultedinsignificantimprovementinuniformityofthefilm.InanapplicationonvapordepositionusingRFplasma,theshapeofthetargetwasmodifiedlobecurvedtocounterthegeometryeffectsof
- 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:
- 电气工程 专业 英语翻译