Decentralized decoupling of multivariable control systems with unmodelled interaction

This paper presents both state space and frequency domain approaches for the decentralized decoupling of multivariable control systems with unmodelled interaction. The controller has a configuration of two degrees of freedom. The nominal controller is tuned to satisfy the eigenvalue specification of the isolated single variable subsystem. The rejection of unmodelled coupling due to the connections or disconnections of other subsystems is controlled by the decentralized compensator. The method assumes that only local information is acquirable, no information from other subsystems and no interconnection parameters are required.