基于PLC的电梯控制系统的设计英文文献

DesignandPracticeofanElevatorControlSystemBasedonPLCXiaolingYang1,2,QunxiongZhu1,HongXu11CollegeofInformationScience&Technology,BeijingUniversityofChemicalTechnology,Beijing100029,China2AutomationCollegeofBeijingUnionUniversity,Beijing,100101,[e-mail],[e-mail],AbstractThispaperdescribesthedevelopmentof2nine-storeyelevatorscontrolsystemforaresidentialbuilding.ThecontrolsystemadoptsPLCascontroller,andusesaparallelconnectiondispatchingrulebasedonminimumwaitingtimetorun2elevatorsinparallelmode.Thepapergivesthebasicstructure,controlprincipleandrealizationmethodofthePLCcontrolsystemindetail.Italsopresentstheladderdiagramofthekeyaspectsofthesystem.Thesystemhassimpleperipheralcircuitandtheoperationresultshowedthatitenhancedthereliabilityandperformanceoftheelevators.1.IntroductionWiththedevelopmentofarchitecturetechnology,thebuildingistallerandtallerandelevatorsbecomeimportantverticaltransportationvehiclesinhigh-risebuildings.Theyareresponsibletotransportpassengers,living,workingorvisitinginthebuilding,comfortableandefficientlytotheirdestinations.Sotheelevatorcontrolsystemisessentialinthesmoothandsafeoperationofeachelevator.Ittellstheelevatorinwhatordertostopatfloors,whentoopenorclosethedoorandifthereisasafety-criticalissue.Thetraditionalelectricalcontrolsystemofelevatorsisarelay-controlledsystem.Ithasthedisadvantagessuchascomplicatedcircuits,highfaultratioandpoordependability;andgreatlyaffectstheelevator’srunningquality.Therefore,entrustedbyanenterprise,wehaveimprovedelectricalcontrolsystemofarelay-controlledelevatorinaresidentialbuildingbyusingPLC.Theresultshowedthatthereformedsystemisreliableinoperationandeasyformaintenance.Thispaperintroducesthebasicstructure,controlprincipleandrealizationmethodoftheelevatorPLCcontrolsystemindetail.2.SystemstructureThepurposeoftheelevatorcontrolsystemistomanagemovementofanelevatorinresponsetouser’srequests.Itismainlycomposedof2parts:2.1.ElectricpowerdrivingsystemTheelectricpowerdrivingsystemincludes:theelevatorcar,thetractionmotor,doormotor,brakemechanismandrelevantswitchcircuits.HereweadoptedanewtypeofLCseriesACcontactorstoreplacetheoldones,andusedPLC’scontactstosubstitutetheplentyofintermediaterelays.Thecircuitsoftractionmotorarereserved.Thustheoriginalcontrolcabinet’sdisadvantages,suchasbigvolumeandhighnoiseareovercomeefficiently.2.2.SignalcontrolsystemTheelevator’scontrolsignalsaremostlyrealizedbyPLC.Theinputsignalsare:operationmodes,operationcontrolsignals,car-calls,hall-calls,safety/protectsignals,dooropen/closesignalandlevelingsignal,etc.AllcontrolfunctionsoftheelevatorsystemarerealizedbyPLCprogram,suchasregistration,displayandeliminationofhall-callsorcar-calls,positionjudgmentofelevatorcar,chooselayeranddirectionselectionoftheelevator,etc.ThePLCsignalcontrolsystemdiagramofelevatorisshowedinFigure1.Figure1PLCsignalcontrolsystemdiagram2.3.RequirementsThegoalofthedevelopmentofthecontrolsystemistocontrol2elevatorsina9-storeyresidentialbuilding.Foreachelevator,thereisasensorlocatedateveryfloor.Wecanusethesesensorstolocatethecurrent2008WorkshoponPowerElectronicsandIntelligentTransportationSystem978-0-7695-3342-1/08$25.00©2008IEEEDOI10.1109/PEITS.2008.4494Authorizedlicenseduselimitedto:BEIJINGINSTITUTEOFTECHNOLOGY.DownloadedonMarch30,2009at00:50fromIEEEXplore.Restrictionsapply.positionoftheelevatorcar.Theelevatorcardoorcanbeopenedandclosedbyadoormotor.Thereare2sensorsonthedoorthatcaninformthecontrolsystemaboutthedoor’sposition.Thereisanothersensoronthedoorcandetectobjectswhenthedoorisclosing.Theelevatorcar’supordownmovementiscontrolledbyatractionmotor.Everyfloor,exceptthefirstandthetopfloor,hasapairofdirectionlampsindicatingthattheelevatorismovingupordown.Everyfloor,hasasevensegmentLEDtodisplaythecurrentlocationoftheelevatorcar.Thefirststepforthedevelopmentoftheelevatorcontrolistodefinethebasicrequirements.Informally,theelevatorsbehaviorisdefinedasfollows.(1)RunningwithasingleelevatorGenerally,anelevatorhasthreeoperationstates:normalmode,fire-protectionmodeandmaintenancemode.Themaintenancemodehasthehighestpriority.Onlythemaintenancemodeiscanceledcantheotheroperationmodesbeimplemented.Thenextisfire-protectionmode,theelevatormustreturntothebottomfloororbasestationimmediatelywhenthefireswitchacts.Theelevatorshouldturntonormaloperationmodewhenthefireswitchisreset.Undernormaloperationmode,thecontrolsystem’sbasictaskistocommandeachelevatortomoveupordown,tostoporstartandtoopenandclosethedoor.Butishassomeconstraintsasfollows:Eachelevatorhasasetof9buttonsonthecarcontrolpanel,oneforeachfloor.Thesebuttonsilluminatewhentheyarepressedandcausetheelevatortovisitthecorrespondingfloor.Theilluminationiscanceledwhenthecorrespondingfloorisvisitedbytheelevator.Eachfloor,exceptthefirstandthetopfloor,hastwobuttonsonthefloorcontrolpanel,onetorequestanup-elevator,onetorequestadown-elevator.Thesebuttonsilluminatewhentheyarepressed.Theilluminationiscanceledwhenanelevatorvisitsthefloor,thenmovesinthedesireddirection.Thebuttonsonthecarcontrolpanelorthefloorcontrolpanelareusedtoco