Aclassoflarge-sealesystems,wheretheoverallobjectivefunctionisanonlinearfunctionofperformanceindexofeachsubsystem,isinvestigatedinthispaper.Thistypeoflarge-scalecontrolproblemisnon-separableinthesenseofconventionalhierarchicalcontrol.Hierarchicalcontrolisextendedinthepapertolarge-scalenon-separablecontrolproblems,wheremultiobjectiveoptimizationisusedasseparationstrategy.Thelarge-scalenon-separablecontrolproblemisembedded,under;ertainconditions,intoafamilyoftheweightedLagrangianformulation.TheweightedLagrangianformulationisseparablewithrespecttosubsystemsandcanbeeffectivelysolvedusingtheinteractionbalanceapproachatthetwolowerlevelsintheproposedthree-levelsolutionstructure.Atthethirdlevel,theweightingvectorfortheweightedLagrangianformulationisadjustediterativelytosearchtheoptimalweightingvectorwithwhichtheoptimaloftheoriginallarge-scalenon-separablecontrolproblemisobtained.Theoreticalbaseofthealgorithmisestablished.Simulationshowsthatthealgorithmiseffective.
