建筑电气英文论文Word文档格式.docx

建筑电气英文论文Word文档格式.docx

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建筑电气英文论文@#@ @#@@#@ARCHITECTURALANDCOLLABORATIVECONTROL@#@SYSTEMSACOMPLEMENTARYSYMBIOSIS@#@-Lookingattoday’scontrolsystemonecanfindawidevarietyofimplementations.Frompurearchitecturaltocollaborativecontrolsystem（CCS）toolkitstohomegrownsystemsandanyvariationin-between.DecisionsonthetypeofimplementationshouldbedrivenbytechnicalargumentsRealityshowsthatfinancialandsociologicalreasonsformthecompletepicture.Anydecisionhasit’sadvantagesandit’sdrawbacks.Reliability,gooddocumentationandsupportareargumentsforindustrialcontrols.Financialargumentsdrivedecisionstowardscollaborativetools.Keepingthehandsonthesourcecodeandbeingabletosolveproblemsonyourownandfasterthanindustryaretheargumentforhomegrownsolutionsoropensourcesolutions.Theexperienceofmanyyearsofoperationsshowsthatwhichsolutionistheprimaryonedoesnotmatter,therearealwaysareaswhereatleastpartoftheotherimplementationsexist.Asaresultheterogeneoussystemshavetobemaintained.Thesupportfordifferentprotocolsisessential.Thispaperdescribesourexperiencewithindustrialcontrolsystems,PLCcontrolledturnkeysystems,theCCStoolkitEPICSandtheoperabilitybetweenallofthem.@#@-INTRODUCTION@#@ProcesscontrolsingeneralstartedatDESYintheearly80thwiththeinstallationofthecryogeniccontrolsystemfortheacceleratorHERA（Hadron-Elektron-Ring-Anlage）.Anewtechnologywasnecessarybecausetheexistinghardwarewasnotcapabletohandlestandardprocesscontrolssignalslike4to20mAinputandoutputsignalsandthesoftwarewasnotdesignedtorunPIDcontrolloopsatastablerepetitionrateof0.1seconds.Inadditionsequenceprogramswerenecessarytoimplementstartupandshutdownproceduresforthecomplexcryogenicprocesseslikecoldboxesandcompetecompressorstreets.@#@Soonitwasnecessarytoaddinterfacestofieldbusesandtoaddcomputingpowertocryogeniccontrols.SincetheinstalledD/3system[1]onlyprovidedandocumentedserialconnectiononamultibusboard,thedecisionwasmadetoimplementaDMAconnectiontoVMEandtoemulatethemultibusboard’sfunctionality.ThenecessarycomputingpowerfortemperatureconversionscamefromaMotorolaMVME167CPUandthefieldbusadaptertotheinhouseSEDACfieldbuswasrunningonanadditionalMVME162.TheoperatingsystemwasVxWorksandtheapplicationwastheEPICStoolkit.@#@SincethisimplementationwassuccessfulitwasalsoimplementedfortheutilitycontrolswhichwerelookingforagenericsolutiontosupervisetheirdistributedPLC’s.@#@ASELECTIONOFPROCESSCONTROLSYSTEMSATDESY@#@DCS（D/3）@#@AsaresultofamarketsurveytheD/3systemfromGSEwasselectedfortheHERAcryogenicplant.ThedecisionwasfortunatebecauseoftheDCScharacteroftheD/3.Thepossibilitytoexpandthesystemonthedisplay-andontheI/OsidehelpedtosolvetheincreasingcontroldemandsforHERA.ThelimitingfactorforthesizeofthesystemisnotthetotalnumberofI/Obutthetrafficonthecommunicationnetwork.Thistrafficisdeterminedbythetotalamountofarchiveddatanotbythedataconfiguredinthealarmsystem.Thetechnicalbackgroundofthislimitationisthefactthatarchiveddataarepolledfromthedisplayserverswhereasthealarmsarepushedtoconfigureddestinationslikealarm-files,（printer）queuesordisplays.@#@SCADASystemswithDCSFeatures（Cube）@#@ThefactthattheD/3systemmentionedabovehadsomehardcodedlimitationswithrespecttotheY2Kproblemwasforcingustolookforanupgradeorareplacementoftheexistingsystem.AsaresultofacallfortenderthecompanyOrsiwiththeirproductCubecameintoplay[2].Theprojectincludedacompletereplacementoftheinstalledfunctionality.ThisincludedtheD/3aswellastheintegrationoftheDESYfieldbusSEDACandthetemperatureconversioninVME.Theprojectstartedpromising.Butsoontechnicalandorganizationalproblemswerepushingthescheduletoit’slimitswhichweredeterminedbytheHERAshutdownscheduledatthattime.Thefinalacceptancetestatthevendorssiteshoweddramaticperformanceproblems.Twofactorscouldbeidentifiedasthecauseoftheseproblems.ThefirstonewasrelatedtotheunderestimatedCPUloadofthe6thgradepolynomialtemperatureconversionrunningat1Hz.ThesecondonewastheadditionalCPUloadcausedbythecomplexfunctionalityoftheexistingD/3system.Hereitwasunderestimatedthateachdigitalandanaloginputandoutputchannelhadit’sownalarmlimitsintheD/3system.InaSCADAlikesystemasCubethebasefunctionalityofachannelistoreadthevalueandmakeitavailabletothesystem.Anyadditionalfunctionalitymustbeadded.Lastnotleasttheloadonthenetworkforpollingallthealarmlimits–typicallyforaSCADAsystem–wasalsodrivingthenetwor