外文文献翻译可编程逻辑控制器PLCWord格式文档下载.docx

外文文献翻译可编程逻辑控制器PLCWord格式文档下载.docx

《外文文献翻译可编程逻辑控制器PLCWord格式文档下载.docx》由会员分享，可在线阅读，更多相关《外文文献翻译可编程逻辑控制器PLCWord格式文档下载.docx（9页珍藏版）》请在冰豆网上搜索。

外文文献翻译可编程逻辑控制器PLC@#@可编程逻辑控制器PLC外文文献翻译@#@（含：

@#@英文原文及中文译文）@#@文献出处：

@#@KinnaD.ProgrammableLogicControllers（PLC）[J].FusionEngineering&@#@Design,2015,2（12）:

@#@72-83.@#@英文原文@#@ProgrammableLogicControllers（PLC）@#@KinnaDarl@#@1Motivation@#@ProgrammableLogicControllers（PLC）,acomputingdeviceinventedbyRichardE.Morleyin1968,havebeenwidelyusedinindustryincludingmanufacturingsystems,transportationsystems,chemicalprocessfacilities,andmanyothers.Atthattime,thePLCreplacedthehardwiredlogicwithsoft-wiredlogicorso-calledrelayladderlogic（RLL）,aprogramminglanguagevisuallyresemblingthehardwiredlogic,andreducedtherebytheconfigurationtimefrom6monthsdownto6days[MoodyandMorley,1999].@#@AlthoughPCbasedcontrolhasstartedtocomeintoplace,PLCbasedcontrolwillremainthetechniquetowhichthemajorityofindustrialapplicationswilladhereduetoitshigherperformance,lowerprice,andsuperiorreliabilityinharshenvironments.Moreover,accordingtoastudyonthePLCmarketofFrostandSullivan[1995],anincreaseoftheannualsalesvolumeto15millionPLCsperyearwiththehardwarevalueofmorethan8billionUSdollarshasbeenpredicted,thoughthepricesofcomputinghardwareissteadilydropping.TheinventorofthePLC,RichardEMorley,fairlyconsidersthePLCmarketasa5-billionindustryatthepresenttime.@#@Ingeneral,theproductivityingeneratingPLCisfarbehindcomparedtootherdomains,forinstance,VLSIdesign,whereefficientcomputeraideddesigntoolsareinpractice.ExistentsoftwareengineeringmethodologiesarenotnecessarilyapplicabletothePLCbasedsoftwaredesignbecausePLC-programmingrequiresasimultaneousconsiderationofhardwareandsoftware.Thesoftwaredesignbecomes,thereby,moreandmorethemajorcostdriver.Inmanyindustrialdesignprojects,morethan50%ofthemanpowerallocatedforthecontrolsystemdesignandinstallationisscheduledfortestinganddebuggingPLCprograms[Rockwell,1999].@#@PLCs（programmablelogiccontrollers）arethecontrolhubsforawidevarietyofautomatedsystemsandprocesses.Theycontainmultipleinputsandoutputsthatusetransistorsandothercircuitrytosimulateswitchesandrelaystocontrolequipment.Theyareprogrammableviasoftwareinterfacedviastandardcomputerinterfacesandproprietarylanguagesandnetworkoptions.@#@ProgrammablelogiccontrollersI/Ochannelspecificationsincludetotalnumberofpoints,numberofinputsandoutputs,abilitytoexpand,andmaximumnumberofchannels.Numberofpointsisthesumoftheinputsandtheoutputs.PLCsmaybespecifiedbyanypossiblecombinationofthesevalues.Expandableunitsmaybestackedorlinkedtogethertoincreasetotalcontrolcapacity.Maximumnumberofchannelsreferstothemaximumtotalnumberofinputandoutputchannelsinanexpandedsystem.@#@PLCsystemspecificationstoconsiderincludescantime,numberofinstructions,datamemory,andprogrammemory.ScantimeisthetimerequiredbythePLCtocheckthestatesofitsinputsandoutputs.Instructionsarestandardoperations（suchasmathfunctions）availabletoPLCsoftware.Datamemoryisthecapacityfordatastorage.Programmemoryisthecapacityforcontrolsoftware.@#@Programmablelogiccontrollersuseavarietyofsoftwareprogramminglanguagesforcontrol.TheseincludeIEC61131-3,sequentialfunctionchart（SFC）,functionblockdiagram（FBD）,ladderdiagram（LD）,structuredtext（ST）,instructionlist（IL）,relayladderlogic（RLL）,flowchart,C,andBasic.TheIEC61131-3programmingenvironmentprovidessupportforfivelanguagesspecifiedbytheglobalstandard:

@#@SequentialFunctionChart,FunctionBlockDiagram,LadderDiagram,StructuredText,andInstructionList.Thisallowsformulti-vendorcompatibilityandmulti-languageprogramming.SFCisagraphicallanguagethatprovidescoordinationofprogramsequences,supportingalternativesequenceselectionsandparallelsequences.FBDusesabroadfunctionlibrarytobuildcomplexproceduresinagraphicalformat.Standardmathandlogicfunctionsmaybecoordinatedwithcustomizablecommunicationandinterfacefunctions.LDisagraphiclanguagefordiscretecontrolandinterlockinglogic.ItiscompletelycompatiblewithFBDfordiscretefunctioncontrol.STisatextlanguageusedforcomplexmathematicalproceduresandcalculationslesswellsuitedtographicallanguages.ILisalow-levellanguagesimilartoassemblycode.Itisusedinrelativelysimplelogicinstructions.RelayLadderLogic（RLL）,orladderdiagrams,istheprimaryprogramminglanguageforprogrammablelogiccontrollers（PLCs）.Ladderlogicprogrammingisagraphicalrepresentationoftheprogramdesignedtolooklikerelaylogic.FlowChartisagraphicallanguagethatdescribessequentialoperationsinacontrollersequenceorapplication.Itisusedtobuildmodular,reusablefunctionlibrar