H∞ output feedback control design for uncertain fuzzy singularly perturbed systems:: an LMI approach

This paper examines the problem of designing a robust H-infinity output feedback controller for a class of singularly perturbed systems described by a Takagi-Sugeno fuzzy model. Based on a linear matrix inequality (LMI) approach, LMI-based sufficient conditions for the uncertain singularly perturbed nonlinear systems to have an H-infinity performance are derived. To eliminate the ill-conditioning caused by the interaction of slow and fast dynamic modes, solutions to the problem are presented in terms of LMIs which are independent of the singular perturbation epsilon. The proposed approach does not involve the separation of states into slow and fast ones and it can be applied not only to standard, but also to nonstandard singularly perturbed nonlinear systems. A numerical example is provided to illustrate the design developed in this paper. (C) 2004 Elsevier Ltd. All rights reserved.