Decentralized guaranteed cost control of a class of large-scale interconnected systems

This paper focuses on a class of large-scale systems with parameter uncertainties and nonlinear perturbations in each subsystem and interconnections. We deal with the design of decentralized state feedback and output feedback controllers such that for all admissible uncertainties and interconnections, the closed-loop large scale system is asymptotically stable and an upper bound of the given quadratic cost is minimized. We first derive a robust performance analysis result in terms of a set of linear matrix inequalities (LMIs). This analysis result is then applied to solve both the decentralized state feedback and dynamic output feedback guaranteed cost control problems. A procedure is given for the minimization of the quadratic cost in terms of LMIs.