Decentralized robust control of uncertain interconnected systems with prescribed degree of exponential convergence

This paper considers the problem of decentralized control of an uncertain interconnected time-varying system which does not satisfy the so-called matching conditions. The uncertainties, which may be decomposed into two portions, a matched portion and a mismatched portion, may appear in the subsystems and also in the interconnections between the subsystems. A robust decentralized control scheme is proposed which guarantees the controlled system to converge exponentially, with a prescribed degree, to a residue set with a prescribed bound when the mismatched portion of the uncertainties satisfies a certain bound condition