《外文翻譯--PLC控制下的電梯系統(tǒng).doc》由會員分享，可在線閱讀，更多相關(guān)《外文翻譯--PLC控制下的電梯系統(tǒng).doc（8頁珍藏版）》請在裝配圖網(wǎng)上搜索。
1、ElevatorSystemBasedonPLCComposedbytheorderofrelaycontrolsystemisarealizationofthefirstelevatorcontrolmethod.However,toenterthenineties,withthedevelopmentofscienceandtechnologyandthewidespreadapplicationofcomputertechnology,thesafetyofelevators,reliabilityoftheincreasinglyhighdemandontherelaycontrolw
2、eaknessesarebecomingevident.Elevatorcontrolsystemrelaysthefailureratehigh,greatlyreducesthereliabilityandsafetyofelevators,andescalatorsstoppedoftentotakewiththestaffabouttheinconvenienceandfear.Andtheeventratherthantakingtheliftorsquatattheendoftheliftwillnotonlycausedamagetomechanicalcomponents,bu
3、talsopersonalaccidentmayoccur.ProgrammableLogicController(PLC)isthefirstorderlogiccontrolinaccordancewiththeneedsofdevelopedspecificallyforindustrialenvironmentapplicationstooperatetheelectronicdigitalcomputingdevice.Givenitsadvantages,atpresent,therelaycontrolthelifthasbeengraduallyreplacedbyPLCcon
4、trol.Atthesametime,ACvariablefrequencymotorspeedcontroltechnology,thewaytheliftdragspeedhasbeenagradualtransitionfromDCtoACfrequencyconverter.Thus,PLCcontroltechnologyincreasesVVVFElevatormoderntechnologyhasbecomeahotindustry.1.PLCelevatorcontroladvantages(1)usedinelevatorcontrolPLC,withsoftwarefora
5、utomaticcontrolofliftoperation,reliabilitygreatlyincreased.(2)layerwasremovedandamajorityoftherelay,thecontrolsystemstructureissimple,tosimplifytheexternalcircuit.(3)PLCcanbeavarietyofcomplexcontrolsystem,easytoaddorchangecontrolfunctions.(4)PLCcanbeautomatedfaultdetectionandalarmdisplaytoimprovethe
6、operationofsecurityandeaseofmaintenance.(5)forthegroupcontroltheallocationandmanagement,andimprovetheefficiencyofelevatoroperation.(6)donotneedtochangethecontrolschemechangeswhenthehardwareconnection.2.VVVFelevatorcontrolcharacteristicsWiththepowerelectronics,microelectronicsandcomputertechnologytoc
7、ontroltherapiddevelopmentoftechnology,communicationtechnologyVVVFalsoaveryrapidrate.ACvariablefrequencymotorspeedcontroltechnologyisthepowertoimprovetheprocessinordertoimproveproductqualityandimprovingtheenvironmentandpromotingtechnologicalprogressasaprimarymeans.Frequencyofitsexcellentperformancean
8、dthespeedbrakefromasmoothperformance,highefficiency,highpowerfactorandpower-savingeffectofabroadscopeofapplicationandmanyotheradvantagesofbeingathomeandabroadrecognizedasthemostpromisingapproachspeedExchangecharacteristicsofVVVFElevator(1)lowenergyconsumption(2)lowloadcircuit,therequiredemergencypow
9、ersupplydeviceofsmallIntheaccelerationstage,therequiredstart-upcurrentoflessthan2.5timestheratedcurrent.Peakstartingcurrentandtimeisshort.Sincethestartingcurrentisdrasticallyreduced,sopowerconsumptionandpowersupplycablediametercanbereducedalot.Requiredforemergencypowersupplydevicesarealsorelativelys
10、mallsize.(3)highreliabilityandlongservicelife.(4)goodcomfortElevatoroperationisbesttofollowthespeedcurveofagivenoperation.Theircharacteristicscanbeadaptedtohumanfeelings,andtoensurethatnoiseoperation,smoothbrakePinglayerandhighprecision(5)Stablenoise-free(6)Inthecar,theengineroomandadjacentareastoen
11、surethatnoise.Becausetheirsystemsuseahighclockfrequency.Alwaysproduceatruesinewavepowersupplycurrentyet.Motortorquerippledoesnotappear.Therefore,toeliminatevibrationandnoise.3.ElevatorcontroltechnologyTheso-calledelevatorcontroltechnologyreferstotheelevatordrivesystemandelectricalcontrolsystemofauto
12、maticcontrol.70asthe20thcenturyinChinaselevatorwasmarkedbytheexchangeoftwo-speedelevator.Itsspeedisusedtochangetheelevatortractionmotoroftheveryfew,twoormulti-levelapproachtothenumberofwindings,veryfewofthemashigh-speedwindingofthewinding,averyfewnumberofwindingsasthelow-speedwinding.Windingsforhigh
13、-speedelevator-speedstart-upandrunning,low-speedwindingsforbrakingandthemaintenanceofelevators.Theearly80s,VVVFinvertercontrolledvariableliftsystemavailable.ItusesACmotordrives,areabletoreachthelevelofDCmotor,controlthespeedofthecurrenthasreached6m/sec.Itssmallsize,lightweight,highefficiency,energys
14、aving,includingthepastalmostalltheadvantagesofthelift.Isthelatestelevatordrivesystem.Operationinverticallift,thereisalsothestartingpointoftheterminusstation.Formorethanthree-storyelevatorbuildings,thestartingpointoftheterminalstationsandstopsbetweenthehadnot,thestartingpointforthesestationsatthefirs
15、tflooroftheterminallocatedatthehighestfloor.Startingpointinthefirstfloorofthestationknownasbasestations,knownasthestartingpointatbothendsoftheterminalstationsandstationsatbothendsofintermediatestopsbetweenstations.Outsidethestationhasacallbox,boxsetareusedbystaffforelevatorcallbuttonortouchthecallbu
16、tton,thegeneralendsoftheliftstationsinthecallboxontheSettingsbuttonortouchofabutton.Middlelayerofthestationsetupthecallboxbuttonortouchbutton2.Nodriversforthecontrolofelevators,atvariousstationsaresetupcallsmeonabuttonortouchbutton.Elevatorcarandtheinternalsettings(exceptfordebriselevator)tomanipula
17、teme.Controlboxswitchonthehandleorsetupstationsandthecorrespondinglayerofbuttonsortouch-buttoncontrolboxonthetouch-controlbuttonorcommandbuttonortouchthecitybutton.Outsidethecommandbuttonortouch-buttonissueasthesignaloutsidethecommandsignal,withinthecommandbuttonortouch-buttonissuewithinthesignalasa
18、commandsignal.80Inthemid-20thcentury,thetouchbuttonhasbeenreplacedbymicro-button.Astheelevatorcallboxoutsidethebasestation,inadditiontosetupacallbuttonortouchbutton,butalsosetakeyswitchinordertoworktheelevatorclearance.Driversormanagementstafftoopentheelevatortothebasestationcanwrigglethroughadedica
19、tedkeytothekeyswitch.Closetheelevatorinplacetoautomaticallycutofftheelevatorcontrolpowersupplyorpowersupply.4.PLCControlElevatorDesignWiththecontinuousdevelopmentofurbanconstruction,theincreasinghigh-risebuildings,elevatorsandlifeinthenationaleconomyhasabroadapplication.Elevatorhigh-risebuildingsasa
20、meansoftransportintheverticalrunofdailylifehasbeeninextricablylinkedwithpeople.Infacttheliftisbasedonexternalcallcontrolsignals,aswellasthelawsoftheirown,suchasrunning,andthecallisrandom,theliftisactuallyaman-machineinteractivecontrolsystem,simpletousecontrolorlogiccontrolordercannotmeetthecontrolre
21、quirements,andtherefore,elevatorcontrolsystemusesarandomcontrollogic.Elevatorcontroliscurrentlygenerallyusedintwoways,first,theuseofcomputerasasignalcontrolunit,thecompletionoftheliftsignalacquisition,operationandfunctionoftheset,toachievetheliftandsettheautomaticschedulingfunctiontoruntheelection,d
22、ragthecontrolfrominvertertocomplete；thesecondcontrolmodewithprogrammablelogiccontroller(PLC)toreplacethecomputercontrolsignalsetstheelection.Fromthecontrolandperformance,thesetwotypesofmethodsandthereisnosignificantdifference.Mostofthedomesticmanufacturerstochoosethesecondapproach,becausethesmallers
23、caleofproduction,theirdesignandmanufactureofhighcostofcomputercontroldevices；andPLChighreliability,convenientandflexibleprogramdesign,anti-interferenceability,stableandreliableoperationofthecharacteristicsofTherefore,theelevatorcontrolsystemisnowwidelyusedtorealizeprogrammablecontroller.5.Elevatorco
24、ntrolsystemcharacteristicsOperationoftheliftcurveisabovethestarttoruncomfortindicatorsliftthekeyfeatures,andcomfortaredirectlyrelatedwiththeacceleration,accordingtocontroltheory,foracertainamountofchangeaccordingtothelawmustbedirectlycontrolled,forelevatorcontrolsystem,accordingtotheidealacceleratio
25、ncurveaccelerationfeedbacktobeused,inaccordancewiththemotortorqueequation:M-MZ=M=J(dn/dt),canbeseenreflectedintherateofchangeofaccelerationofthesystemofdynamictorquechangesonthecontrolsystemtocontroltheaccelerationofthedynamictorqueM=M-MZ.Therefore,duringthistimetocontroltheuseoftheprincipleofaccele
26、ration,whenthestartrateofincreaseinsteady-statevalueabove90%,theaccelerationcontrolsystembytheswitchtospeedcontrol,asinparagraphsteadyspeed,speedcontrolfortheconstantfluctuationsinthesmaller,littlechangeinacceleration,speedandtheuseofclosed-loopcontrolcanmaintainasteady-statespeedaccuracyandprecisionforthebrakingsectiontocreatetheconditionspinglayer.Isrisingatarateinthesystem,andalthoughtheabove-speedPIregulatorusedtocontrol,buttwoofthePIparametersaredifferentinordertoimprovethesystemdynamicresponseindicators.Thebrakeinthesystem,
外文翻譯--PLC控制下的電梯系統(tǒng).doc
