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卷扬机论文中英文资料外文翻译文献英文原文ControlofElectricwinchFormotorcontrol,weknowthebestwayistousethestylebuttonstomovethemanysimplemanualconsole.Andthisconsole,insomeapplicationsmaystillbeagoodchoice,assomecomplexcontrolheadachecanalsobeused.Thisarticledescribesinyourdesign,buildorpurchasewinchcontroller,youhavethemotor'sbasicelectricalequipmentandyouwillneedtoaddresstheuserinterfacecommandaddressed.First,themanualshouldbeamanualcontrolconsoletype,soifyouremoveyourfingerbuttons,hoistwillstop.Inaddition,eachcontrolstationequippedwithanemergencyneedtobrake,hoisttheemergencybraketocutoffallpower,notjustthecontrolcircuit.Thinkaboutit,ifthehoistatthestop,itdidnotstop,youdoneedawaytocutoffthefaultlineprotectionpower.Setthetableinthecontrolofakeyoperatedswitch,isalsoaverygoodidea,especiallyinthelineleadingtotheworkstationcannotcontrol,youcanusetheswitch.(inthedesignoftheconsole,eventhesimplestmanualconsole,butalsoconsidersettingbyspecializedpersonneltooperatethesafeoperationofthekeys.)ConstantspeedmotorcontrolForafixedspeedwinchactualcontroldeviceisathree-phasestarter.Turnthemotorisreversed,byasimpleswitchcontrolledphasetransformationsequencefromABCtoCBA.Theseactionsarecompletedbytwothree-polecontactor-style,andtheyareinterlocked,sothattheycannotbesimultaneouslyclosed.NEC,requiredinadditiontooverloadandshortcircuitprotectiondevices.Toprotectthemotoragainstoverloadduetomechanicaleffectscausedbyoverheatingintheheattobeinstalledinsidethestarteroverloaddelaydevice.Whentheheatoverloaddelaydeviceoverheating,ithasalongdoubleoffthemetalmotorpower.InadditionInaddition,youcanalsoselectathermistorcanbeinstalledinthemotorwindingway,itcanbeusedtomonitormotortemperaturechanges.Fortheshort-circuitprotection,wegenerallyusedbymotorfusestoachieve.Alinearcurrentindependentcontactors,thecontactorsareconfiguredshouldbemorethanthecurrentmaincircuitcontactor,soastoachievethepurposeofredundancy.Thissetsthecurrentcontactoriscontrolledbythesecuritycircuit,suchas:emergencybrakeandthemore-waylimits.Wecanusethelimitswitchestoachievetheaboveoperation.Whenyoureachtheendofthenormaltravellimitposition,thehoistwillstop,andyoucanonlymovethewinchintheoppositedirection(ie,thedirectionawayfromthelimitposition.)Thereisalsoneedforamorelimitedwayjustincase,duetoelectricalormechanicalproblems,leavingtheoperationofhoistlimitbitmorethannormal.Ifyourunintomorelimiter,linearcontactorwillopen,therefore,cannotbedrivenwinchwillexceedthislimitposition.Ifthishappens,youneedtoaskaprofessionaltechniciantochecktheleadtomeetthemorespecificreasonslimiter.Then,youcanusethestartertoggleswitchinsidetheelasticrecoveryprocesstodealwithmoreproblems,ratherthantrippingdeviceorahand-offthecurrentcontacts.AnecessaryconditionforspeedOfcourse,thesimplefixedspeedstarterisreplacedbyvariablespeeddrives.Thismakesthingsstarttogetinterestingagain!Ataminimum,youneedtoaddaspeedcontroldialoperationplatform.Joystickisabetteruserinterface,becauseitmakesyoumovepartsofamoreintuitivecontrol.Unfortunately,youcannotjustfromyourlocalconsoletosendcommandstocontroltheoldvariablespeeddrives,inaddition,youcannotwantitintheinitialstages,willbeabletoenhancethesafeandreliableanddecentralizedfacilities.Mostofthevariablespeeddrivecannotachievetheserequirements,becausetheyarenotdesignedtodoupgradingwork.Driversneedtobesettoreleasethebrakebeforethemotorcangeneratetorque,andwhenparking,thatis,beforetherevocationoftorque,thebrakewillbethefirstaction.Formanyyears,DCmotorsanddrivesprovideanumberofcommonsolutions,suchaswhentheyareinavarietyofspeedswithgoodtorquecharacteristics.FormostofthehoistofthelargedemandforDCmotorisveryexpensive,andthatthesametypeofACmotorthanthemuchmoreexpensive.AlthoughtheearlyACdrivesarenotveryuseful,astheyhaveaverylimitedscopeofapplicationofthespeed,butproducedonlyasmalllow-speedtorque.Now,withtheDCdrivesthedevelopmentoflowcostandalargenumberofavailableACmotorshasledtoacommunication-drivenrevolution.VariablespeedACdrivesintwoseries.Frequencyconverterhasbeenwidelyknownand,indeed,easytouse.ThesedrivesconvertACintoDC,andthen,andthenconvertitbacktoexchange,theexchangeaftertheconversionisadifferentfrequency.Ifthedriveproducedtheexchangeof30Hz,60Hzanormalmotorwillrunathalfspeed.Theoretically,thisisverygood,butinpractice,thiswillhavealotofproblems.Firstofall,atypicallinearmotor60Hzfrequenciesbelow2Hz3Hzareaortherewillbeerrors,andstartcog(thaturgentpush,yank),orparking.Thiswilllimityourspeedrangelowerthan20:1,almostnotadaptedtotheoperationalphaseofthefineadjustment.Second,manylow-costconverterisnotabletoprovidetheratedtorqueatlowspeeds.Useofthesedrives,willresultintherapidmovetoupgradethecomponentsorcompletefailure,precisely,whenyoutrytoupgradeastablescientificinstruments,youdonotwanttoseethissituation.Somenewinverterisaclosed-loopsystem(togetfeedbackfromthemotortoprovideamoreaccuratespeedcontrol),andthemotorwillworkquitewell.AnotherseriesofACdrivesistheflowvectortypedrive.Thesecomponentsrequireinstallationofthespindlemotorencoder,encodermakesuseofthesedrivescanaccuratelymonitortherotationofthemotorarmature.Pr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