ControlofacontinuoustandemcoldmetalrollingprocessContentsabstractIntroductionMathematicalmodelSimulationsConclusionabstractThecontinuoustandemcoldrollingofmetalstripisacomplexmultivariableprocesswhosecontrolpresentsengineeringchallengesinadditiontothosegenerallyencounteredinthecaseofthestandalonecoldrollingprocess.IntroductionThetandemcoldrollingprocessconsistsofpassingametalstripthroughasequenceofpairsofindependentlydrivenworkrolls,witheachworkrollsupportedbyabackuprollofalargerdiameter.Fig.1showsatypicalfive-standcoldrollingprocess.

(SDRE)techniqueInprevious,ithasbeenshownbysimulationthatthestate-dependentRiccatiequation(SDRE)techniqueenhancedbyappropriatetrimmingfunctionshasanexcellentpotentialforimprovingtheperformanceofthestand-alonetandemcoldrollingprocess.MathematicalmodelTheexpressionswhichcomprisethemodelareputintotheformofastate-spacemodelwhichisdescribedbyEqs.(1)and(2):ControllerforthecontinuousmillTheSDREtechniqueasaugmentedforcontrolofthestand-alonemillisthebasisforcontrolofthecontinuousmill.ThecapabilityofthiscontrollertoreduceexcursionsinthicknessandtensionduringaspeedchangewasverifiedpreviouslyWeldpassageconsiderationsAnoperatingpointisdeterminedbytheproductbeingrolledandthedesiredmillspeed.Duringweldpassage,theoperatingpointischangedfromtheoperatingpointforthepresentstriptotheoperatingpointforthenextstrip.Thischangeintheoperatingpointrequiresthatthecontrollerreferencesforthestripthickness,striptension,positionactuator.TechniqueATechniqueBSimulationsVerificationofperformanceduringspeedchangeActuatorpositionpathPerformanceverificationPerformanceinthepresenceofdisturbancesanduncertaintiesMassflowevaluationCompanyLogoConclusionInthispaperithasbeenshownthattheSDREtechniqueasaugmentedforstand-alonetandemcoldrollingwithenhancementsforcontrolduringweldpassagehasanexcellentpotentialforsuccessfullycontrollingthecontinuoustandemcoldrollingprocess.ReferencesBinroth,C.,&Fedosseev,A.(2006).Behaviorofweldseamsduringcoldrollingprocesses.InProceedingsofthe9thinternationaland4thEuropeansteelrollingconference.Paris.Bryant,C.F.(1973).Automationoftandemmills.London:TheBritishIronandSteelInstitute.Cloutier,J.R.,D’Souza,N.,&Mracek,C.P.(1996).NonlinearregulationandnonlinearHNcontrolviathestate-dependentRiccatiequationtechnique:Part1,theory.In