基于S7-300-PLC的機(jī)械手臂控制系統(tǒng)設(shè)計設(shè)計

第頁Abstract-AsupervisoryandcontrolsystemforoiltanksareabasedonPLCS7-300andconfigurationsoftwareForceControlisintroducedinthispaper.Thehardwarestructureofthesystemandthesoftwaredesignarebothdescribedindetail.Inthissystem,SuperiorcomputerscommunicatewithPLCthroughIndustrialEthernet.ThesuperiorcomputerssystemadoptsduplexredundancyandthePLCadoptssoftwareredundancy.ThismonitoringsystemintegratesthemeritofPLCandcomputerandimprovesthereliability.Keywords-PLC,configurationsoftware,supervisoryandcontrolsystem,softwareredundancyI.INTRODUCTIONWiththeincreasingcompetitionoftheoilmarket
oildepotsareplayingamoreandmoreimportantrole,andithasbecomealong-termimportantjobtosuperviseandcontroltheoperationstateofoildepots.ThispaperdesignsasupervisoryandcontrolsystemforaoildepotinShandongProvince.Thisoildepotcollectedtankinformationandcontrolledvalvesmanuallybefore.Thereweresomeshortcomingsinitsuchasslowsupervisory,greaterrorandlowreliability.Soitisnecessarytoestablishabettersupervisoryandcontrolsystemthatistimely,accurateandreliable.ProgrammablelogiccontrollersPLChavebeenwidelyusedintheindustrialcontrolfieldsbecauseofitsmeritssuchassimplestructure,flexiblefunctions,highreliabilityandstrongabilityincommunication.Computershaveadvantagesinthedatadisplayandstorage,aswellasinhuman-computercommunications.ThispaperdesignsasupervisoryandcontrolsystemforoiltanksareabasedonPLCandcomputer.PLCisthecontrolcentreanditcompletesallthedetailsofthecontroltask.ItconnectswithdigitalandanalogsignalsoffielddevicesthroughgeneralI/Ointerfaces,collectsandprocessfielddataaccuratelyandquickly,andcompletesthelogic,timing,countingandmathematicaloperationseasily.Computersprovidehuman-machineinterface,displaythefeildworkingstastedynamicly,andmakestheoperationeasy.ThesystemcombinestheadvantagesofPLCandcomputer,providesaremotereal-timemonitoringforthetanksarea,ensuresafetyandreliabilityandimprovestheworkefficiency.Consideringoildepot’shighrequirementsonreliabilityandcontinuity,redundancyschemeisdesignedtoimprovethereliabilityfurther.II.HARDWAREOFTHESYSTEMtheOverallstructureandfunctionsFig.1OverallstructurediagramofthesystemThestructureofthesupervisorysystemisshowninFig.1.Therearethreelevelsinthesystem:thefirstlevelissuperiorcomputers.TheyconsistofdualredundantIndustrialComputersinstalledwithconfigurationsoftwareForceControlandplacedinthemonitoringcenterroom,thesecondlevelisS7-300PLCthatadoptssoftwareredundancyandisplacedinthelocalcontrolrooms,andthefielddevicesincludingelectricallyoperatedvalvesandliquidlevelswitchesformthethirdlevel.IndustrialComputersareconnectedtotheIndustrialEthernetthroughgeneralnetworkcardsandPLCisconnectedtothesamenetbyEthernetcommunicationmodule,sotheycouldaccomplishthecommunicationbyusingTCP/IPprotocol.PLCcollectsfeedbackdatesofelectricallyoperatedvalves,collectsthestatusofliquidlevelswitchesandopensorclosesvalvesaccordingtothecommandfromsuperiorcomputersandthecontrolprogramintheCPUmodule.Inaddition,PLCcompletestheinterlockcontrolofvalveandliquidlevelswitch.ByexchangingdatawithPLC,superiorcomputersinstalledwithForceControl,monitorelectricallyoperatedvalvesandliquidlevelswitchesinrealtimeandgivecommandtoPLCtocontrolthevalves.Redundancystructureisadoptedinthesystem.ForceControlhastakentheleadinprovidingcompletesupportforredundancyamongtheChina-madeconfigurationsoftwareproducts,anditsupportsdeviceredundancy,networkredundancyandsuperiorcomputerredundancy.Therearetwosuperiorcomputersinthesystem,primarystationandsecondarystation.Innormalconditions,onlytheprimarystationcommunicateswithPLCandthedatainthesecondarystationsynchronizewiththeprimarystationtomakeabackup.Iftheprimarystationfails,thesecondarytakesoverthejob.Andthejob20093rdInternationalConferenceonPowerElectronicsSystemsandApplicationsDigitalReference:K210509077couldcomebacktotheprimarystationormanuallyaftertheprimarystationreturnsnormal.ForceControlsupportsPLCredundancyandnormallycommunicationswiththemasterstationofthePLC.IfthemastersystemofPLCisintheeventoffailure,thecontroljobwouldbetakenoverbythereservesystem,ForceControlwoulddisconnectthecommunicationaccordingtotheswitchflagandturntothereservestationtoexchangedates.B.HardwareDesignofPLCSystemBeforeselectingPLCmodules,analyzethecontrolledobjecttocountoutI/Opoints.Thecurrentrequirementand20%-30%marginshouldbeconsidered,allowingthesystemtoexpand.Accordingtothisprinciple,I/Opointsareasfollows:125digitalinputs,21analoginputs,84digitaloutputs.Basedontheanalysisofcontroltask,thesystemchoosesSiemensS7-300seriesofproducts.ThisseriesPLCcouldMeetrequirementsofthemedium-performancecontrolsystemandadoptmodularstructure.Manydifferentmodulescanbecombinedtogetherandusersshouldselectappropriatemodulesaccordingtotheactualneed.PLCmodulesselectedareshowninTable1.PLCinthesystemconsistsoftwoS7-300stationseachwithaCPU315-2DPandtwoET200Mslavestations.ItsstructureisshowninFigure2.TheEthernetcommunicationmoduleCP343-1providesastandardRJ45interface,oneofthefunctionsistoconnectthePLCtoIndustrialEthernettocommunicatewithcomputers,andtheotherfunctionistoprovideredundantbackuplinkformasterCPUandreserveCPUtorealizeredundantcommunicationbetweenthetwoCPUs.Fig.2HardwarestructureofPLCCPU315-2DPprovidesDPmasterinterfaceandIM153-2ofET200MprovidestwoDPslaveinterfaces,oneisconnectedtothemasterstationandtheothertothereservestationthroughPROFIBUS-DPnetworks.PROFIBUS-DPcouldbeShieldedTwistedPair(RS485)networkphysically.NormalET200Mconsistofarail,ainterfacemoduleandsomegeneralmodules.Themodulesexceptpowersupplyareconnectedthroughbusconnectors.Thisstructuredoesn’tsupportredundantcyfunctions.Thereisanotherconfigurationthatissuitableforredundantcy.Itusesaspecialrailthatcantakeactivebusmodulesandtwointerfacemodules.Themodulesexceptpowersupplyaremountedontheactivebusmodulesanditispossibletochangemodulesduringrunning.C.ConnectionsoftheElectricallyOperatedValveHenchunCKDserieselectricoperatorsareusedandFig.3showsitsconnectionmethod.Thefeedbackofelectricallyoperatedvalveincludesfourdigitalsignalsandoneanalogsignal.Digitalsignalsareremotemodeindicatingcontact,fullopenindicatingcontact,fulloffindicatingcontactandcommonalarmcontact.Theanalogfeedback,a4-20mAcurrent,showsthevalve’sopeningvalue.Whenthevalveisintheremotecontrolmode,digitaloutputsofPLCdrivetherelaysandthencontrolthevalves.Fouroutputcontrolsignalsincludeopen-valvesignal,close-valvesignal,stopsignalandemergencyprotectionsignalesd.Fig.3ValveconnectiondiagramIII.SOFTWAREOSTHESYSTEMSoftwareinthesystemincludestwomajorparts,PLCprogrammingsoftwareSTEP7V5.4andsuperiorcomputerconfigurationsoftwareForceControlV6.0.A.CommunicationbetweenSuperiorComputerandPLCForceControldevelopsaspecialdriverfortheS7-300PLC,20093rdInternationalConferenceonPowerElectronicsSystemsandApplicationsDigitalReference:K210509077thereforeitisnotnecessaryfortheuserstobefamiliarwiththecommunicationprotocolbetweenthem,andneithernecessarytoprogramorconfigurenetworkinthePLC,thecommunicationbetweenPCandPLCcanbeachievedeasily.ThemainprobleminthissystemisthatduetoPLC'ssoftredundantstructure,whenthecontroltaskswitchestoresereveCPUfromthemasterone,ForceControlshouldswitchtothecorrectcommunicationobjecttoexchangedatas.Forthispurpose,whendevicePLCiscreatedinForceControl,itshouldbeconfiguredproperlyandadatapointshouldbedefinedinthereal-timedatabaseasaredundancyswitchingflag.FirstconfigureI/OdeviceforForceControl,createPLCwhoseequipmentaddressissetto2,ifsetto1,ForceControlwillnotbeabletoconnecttothePLC.ThestandbychannelisenabledandthedeviceIPaddressandstandbyIPaddressshouldcorrespondwithPLC’stwoEthernetcommunicationmodulesCP343-1.AfterI/OdevicePLCiscreated,defineadatapointinreal-timedatabasewhosedatatypeisselectedas"redundancyswitchingflag".Theflag’svalueis0innormalstate,whenitsvalueis1,ForceControlwillswitchtoPLC’sanotherIPaddress,thenthevalue1willbeclearedautomatically.HerethedatapointislinkedwithMW16ofPLC.CorrespondingprogramisloadedintoPLC,whentheCPUisworkingasmasterstation,MW16issetto0,whentheCPUisworkingasreservestation,MW16issetto1,programinPLCisasfollows:LDB5.DBB9LW#16#2AWSRW1TMW16B.SoftwareofSuperiorComputerForceControlconfigurationsoftwaresolvesproblems(1)CreatingaI/OdevicePLC(2)Creatingareal-timedatabaseandlinkingthedatapointswithdatasinPLC;(3)Drawinggraphicalinterfacestodisplaytheworkstateoftankareaandthestateofalarmsignalsandtodisplaytheoperationbuttons;(4)Interconnectingthegraphicswiththevariablessothatgraphicswillchangewiththedatastomakesoundandlightalarms;(5)Programmingactionscripttocontrolvalves.Whenthebuttonispressed,amouseeventwillbetriggeredandthenthecorrespondingscriptprogramwillbeclose-valveflagorstopflagto1or0.C.SoftwareofPLCFunctionsthatSTEP7completesinthesystemare:(1)Hardwareconfiguration.Createaprojectwithtwostations(e.g.stationAandstationandthenopenstationA.SelectamodulerackforstationA,insertthepowersupplyunit,theCPU315-2DPandCP343-1,establishaPROFIBUSDPnetworkandanEthernetnetwork,insertandconfigureET200M.OpenstationB,createanewPROFIBUSDPnetwork,connectCP343-1tothesameEthernetnetworkwithA,copyET200MofstationAbecausetheconfigurationofET200Mmustbeidenticalonbothstations.(2)Networkconfiguration.OpenthenetworkconfigurationwindowNetpro,createaconnectionbetweenstationAandstationB,selectconnectiontypeISO.(3)Writingsoftwareredundancyprogram.SoftwareRedundanyPackageprovidesthelibrarySWR_LIBthatcontainsspecialFBandFC.InvoketheseFBandFCincorrespondingOBaccordingtotherequirementsoftheSiemenssoftwareredundancymanual;(4)WritingtheprogramforvalvecontrolFig.4VariablerelationFig.4showstherelationshipamongvariablesinForceControl,inPLCandinelectricvalves.Becausetherearealargenumberofvalvestocontrolinthesystemandthecontrolmethodsarethesame,aspecialfunctionFC1forvalvecontroliswritteninordertosimplifythestructureoftheprogram.Fig.5istheflowchartofFC1.Thevalvehastwocontrolmodes,localcontrolmodeandremotecontrolmode.ItisnecessarytojudgewhetherthevalveisintheremotemodebecauseonlyinthismodecanthevalvebecontrolledbythePLC.Valveopeningprocessisasfollows:clickthemouseonopen-valvebuttoninForceControl’sgraphicalinterface,theopen-valveflaginPLCissetto1ifmouseisdown,thenreturnto0ifmousereturnsup,PLCenergizestheopen-valverelayfor1secondaccordingtotherisingedgeofopen-valveflag,comparestheactualvalveopeningwiththepresetvalue,oncetheformerisequaltoorgreaterthanthelatter,energizesthestoprelayfor1secondimmediately.Valveoffprocessissimilarwiththeaboveprocess.Whenthehigh-levelswitchalarms,PLCdrivestheesdrelay,thenvalvewillopen.20093rdInternationalConferenceonPowerElectronicsSystemsandApplicationsDigitalReference:K210509077IV.CONCLUSIONSuperiorcomputersinwhichForceControlconfigurationsoftwareareinstalledprovidegoodhuman-machineinterface,communicatewithPLCthroughIndustrial.Ethernet,thensuperviseandcontrolthesystem.PLCperformreliableandeffectivecontrol.Dualredundancyandsoftwareredundancyisadopted,improvingthereliabilityofthesystemgreatly.ThissystemcombinestheadvantagesofcomputerandPLC,providessimpleinterfaceandhighreliability,makesoperationeasy,andimprovestheautomaticleveloftheoildepot.REFERENCES[1]LiuMeijun.SiemensS7-PLCApplicationandMaintenance,ChinaMachinePress,2008[2]BeijingSunwayForceControlTechnologyCo.Ltd..Graphicalinterfaceanddevelopmentsystem,Beijing,2007[3]SiemensLtd.,China.SoftwareRedundancyforSIMATIICS7-300andS7-400,SiemensLtd.,China,IndustrySector,IndustryAutomation&DriveTechnologies,2008[4]SiemensLtd.,China.ET200MDistributedI/Ooperationmanual,SiemensLtd.,China,IndustrySector,IndustryAutomation&DriveTechnologies,2004Fig.5Valvecontrolflowchart中文譯文基于PLC和組態(tài)軟件的原油儲罐區(qū)監(jiān)督與控制系統(tǒng)摘要—這篇論文介紹了基于plc300控制系統(tǒng)及其組態(tài)軟件的監(jiān)控系統(tǒng)。系統(tǒng)硬件結(jié)構(gòu)和軟件設(shè)計都進(jìn)行了較為詳細(xì)的論述。在這個系統(tǒng)中,優(yōu)越的電腦通過工業(yè)以太網(wǎng)與PLC連接。優(yōu)越的計算機(jī)系統(tǒng)采用雙冗余和PLC采用軟件冗余。該監(jiān)測系統(tǒng)集成PLC與計算機(jī)的優(yōu)點提高了可靠性。關(guān)鍵詞PLC組態(tài)軟件高性能控制系統(tǒng)軟件冗余一、簡介隨著競爭競爭日益激烈的原油市場，倉庫正在發(fā)揮著越來越重要的作用,監(jiān)督和控制油庫運(yùn)行狀態(tài)已成為一個長期的重要的工作。本文在山東設(shè)計了一個油庫監(jiān)督和控制系統(tǒng)。該系統(tǒng)在控制閥門手動之前收集油庫信息。以前它有一些缺點,比如緩慢的監(jiān)督,重大錯誤,很低的可靠性。因此有必要建立一個更好的能夠及時、準(zhǔn)確、可靠的監(jiān)督和控制系統(tǒng)?？删幊绦蜻壿嬁刂破鱬lc廣泛用于工業(yè)控制領(lǐng)域因為它的優(yōu)點結(jié)構(gòu)簡單,靈活的功能,可靠性高和較強(qiáng)的溝通。電腦在數(shù)據(jù)顯示和存儲方面具有優(yōu)勢,以及在人機(jī)通信方面。本文設(shè)計了一個基于PLC和電腦的油庫監(jiān)控系統(tǒng)?？删幊绦蚩刂破?PLC)作為控制中心完成所有細(xì)節(jié)控制任務(wù)。它通過通用I/O接口連接到數(shù)字和模擬信號的現(xiàn)場設(shè)備、準(zhǔn)確、快捷的收集和傳輸數(shù)據(jù),并容易的完成邏輯、時間、計數(shù)和數(shù)學(xué)運(yùn)算。計算機(jī)提供人機(jī)界面,顯示工作動態(tài),使操作很容易。該系統(tǒng)結(jié)合了PLC和電腦的優(yōu)點,提供了一個遠(yuǎn)程實時監(jiān)控的油庫,確保了安全和可靠性和提高工作效率。鑒于油庫對可靠性和連續(xù)性的高要求、冗余方案進(jìn)一步了提高了儀表的可靠性。二、系統(tǒng)硬件組成A總結(jié)構(gòu)和作用圖1系統(tǒng)總體結(jié)構(gòu)框圖介紹了監(jiān)控系統(tǒng)的結(jié)構(gòu)被顯示在圖。1、該系統(tǒng)具有三層:第一級為優(yōu)越的電腦。它們是由雙冗余工業(yè)計算機(jī)安裝配置軟件控制放置在監(jiān)控中心的房間里。第二個層次是S7-300PLC采用軟件冗余，被放置在當(dāng)?shù)乜刂剖?第三層次包括電動閥和液位開關(guān)。工業(yè)電腦通過一般網(wǎng)卡連接到工業(yè)以太網(wǎng)，PLC通信模塊連接到相同的以太網(wǎng),所以它們能夠采用TCP/IP協(xié)議完成通信?？删幊绦蚩刂破?PLC)收集電動閥的反饋數(shù)據(jù),檢測液位開關(guān)的狀態(tài)，根據(jù)電腦和控制模塊的命令打開或關(guān)閉開關(guān)。另外,PLC完成控制閥門和液位開關(guān)的聯(lián)鎖。通過和可編程序控制器(PLC)交換數(shù)據(jù),安裝ForceControl的優(yōu)越的電腦、準(zhǔn)確的監(jiān)控電動閥和液位開關(guān)和給命令給可編程序控制器(PLC)控制閥門。采用冗余結(jié)構(gòu)系統(tǒng)。在中國制造的組態(tài)軟件產(chǎn)品，F(xiàn)orceControl已率先提供完整的支持冗余的系統(tǒng),它支持設(shè)備冗余、網(wǎng)絡(luò)冗余和超級電腦冗余。在系統(tǒng)中有兩臺高級計算機(jī)、一次站和二次站。在正常條件下,只有一次站與PLC相連，二次站作為一次站的備份。如果一次站連接失敗,二次接管這項工作。當(dāng)一次站恢復(fù)正常后能夠自動或手動的接著工作。ForceControl支持PLC冗余和plc的正常通訊。如果掌握系統(tǒng)的可編程邏輯控制器(PLC)發(fā)生故障,儲備體系將接管控制工作,ForceControl會斷開連接，根據(jù)開信號而轉(zhuǎn)向儲備站交換數(shù)據(jù)。BPLC控制系統(tǒng)的硬件設(shè)計在選擇PLC模塊之前,分析了控制項目數(shù)出I/O點數(shù)。應(yīng)考慮當(dāng)前的要求和20%-30%的預(yù)留,以適應(yīng)的系統(tǒng)擴(kuò)展。根據(jù)這一原理,I/O點數(shù)如下:125數(shù)字輸入、21模擬輸入,84數(shù)字輸出。再此分析的基礎(chǔ)上,該系統(tǒng)選擇了西門子S7-300系列的產(chǎn)品。本系列可編程序控制器(PLC)可以滿足要求的采用模塊化結(jié)構(gòu)控制系統(tǒng)。許多不同的模塊可以結(jié)合一起,用戶應(yīng)該根據(jù)實際需要選擇適當(dāng)?shù)哪K?？删幊绦蚩刂破?PLC)模塊選擇顯示在表1。表1:硬件的可編程序控制器(PLC)該系統(tǒng)由)兩個S7-300可編程序控制器(PLC）組成每處理器315-2-DP和兩個副站ET200M，采用的結(jié)構(gòu)是如圖2所示。以太網(wǎng)通訊模塊CP343-1提供了一個標(biāo)準(zhǔn)RJ45界面,其中一個作用使PLC連接到工業(yè)以太網(wǎng),然后再連接到電腦。另一個功能是提供冗余備份鏈接主CPU和儲備處理器實現(xiàn)兩個CPU之間的溝通。圖二硬件結(jié)構(gòu)CPU315-2DP提供主接口和IM153-2DP提供了兩個ET200MDP的副接口,通過profibus-dp網(wǎng)絡(luò)站一個連接到主站，一個連接到儲備站。RS485網(wǎng)絡(luò)可以屏蔽profibus-dp。ET200M通常是由一些線、界面模塊和一些通用的模塊。該模塊除電源都連接在總線上.這種結(jié)構(gòu)并不支持冗余功能。有另一個適合redundantcy配置。它使用一種特殊的軌道,可以采取積極的總線模塊和兩個接口模塊。除了電源模塊外，其它都安裝在活躍的總線模塊上，是有可能的在運(yùn)行時改變模塊的。C連接之電動閥門使用HengchunCKD系列電動開關(guān)圖3顯示它的連接方法。反饋的電動閥門包括四個數(shù)字信號和一個模擬信號。數(shù)字信號遠(yuǎn)程模式聯(lián)系標(biāo)注,斷開聯(lián)系標(biāo)注,連接聯(lián)系標(biāo)注和普通報警指示標(biāo)注。模擬反饋,一個4-20mA電流,顯示閥門的開啟時刻。當(dāng)閥門處于遠(yuǎn)程控制模式,數(shù)字輸出的PLC驅(qū)動繼電器,然后控制閥門。四個輸出控制信號包括開通信號,關(guān)斷信號和緊急停止、保護(hù)信號。三軟件操作系統(tǒng)軟件系統(tǒng)包括兩個主要部分,可編程序控制器(PLC)的STEP7V5.4和ForceControlV6.0。A:電腦和可編程序控制器(PLC)之間的通訊ForceControl開發(fā)了針對S7-300PLC的一個特殊的驅(qū)動器,因此對于用戶來說沒有必要熟悉他們之間的通信協(xié)議,和程序或配置網(wǎng)絡(luò)，可以很容易實現(xiàn)PC與PLC之間的通信。這個系統(tǒng)的一個主要問題是由于PLC的軟件冗余結(jié)構(gòu),當(dāng)控制任務(wù)開關(guān)從主存儲器斷開CPU,ForceControl應(yīng)該和正確的對象交換數(shù)據(jù)。為了這個目的,當(dāng)裝置可編程序控制器(PLC)在ForceControl建立,它該配置適當(dāng)，實時的數(shù)據(jù)庫應(yīng)該被建立，作為一個冗余切換標(biāo)志。ForceControl配置的第一個I/O設(shè)備,創(chuàng)造可編程序控制器(PLC)其設(shè)備地址設(shè)置為2,如果設(shè)置為1,ForceControl將不能連接PLC。備用通道的啟用和設(shè)備的IP地址備用的IP地址須與可編程序控制器(PLC)的兩個CP343-1以太網(wǎng)通信模塊相連接。在I/O設(shè)備創(chuàng)建以后,定義一數(shù)據(jù)點實時數(shù)據(jù)庫的數(shù)據(jù)類型選為“冗余切換標(biāo)志”。標(biāo)志的值正常狀態(tài)是0,當(dāng)它的值為1時,ForceControl將轉(zhuǎn)向另一個IP地址,然后1的值被自動清除。這里的數(shù)據(jù)點連接MW16PLC。相應(yīng)的程序裝入可編程序控制器(PLC),當(dāng)工作的CPU是主