Abstract
This paper concerns the problem of decentralized dynamic output feedback (DOF) H-infinity control for large-scale nonlinear systems with nonlinear interconnections and time-varying delays. Each nonlinear subsystem in the considered large-scale system is represented by a Takagi-Sugeno (T-S) model, and the time delay of each subsystem is assumed to be of an interval-like type. We propose a model transformation to reformulate the decentralized DOF H-infinity control problem into the context of input-output (IO) stability. By introducing a Lyapunov-Krasovskii functional (LKF) that all Lyapunov matrices are not required to be positive definite, and combining with the scaled small gain (SSG) theorem, less conservative results to the decentralized DOF H-infinity controller design of the large-scale T-S fuzzy system are derived in terms of linear matrix inequalities (LMIs). Two numerical examples are given to validate the advantage of the proposed method. (C) 2015 Elsevier B.V. All rights reserved.