# ROBUST $H_{\infty}$ CONTROL FOR T–S TIME-VARYING DELAY SYSTEMS WITH NORM BOUNDED UNCERTAINTY BASED ON LMI APPROACH

Document Type: Research Paper

Authors

Department of Mathematics, Beijing Institute of Technology, Beijing 100081, China

Abstract

In this paper we consider the problem of delay-dependent robust
H1 control for uncertain fuzzy systems with time-varying delay. The Takagi–
Sugeno (T–S) fuzzy model is used to describe such systems. Time-delay is
assumed to have lower and upper bounds. Based on the Lyapunov-Krasovskii
functional method, a sufficient condition for the existence of a robust $H_{\infty}$
controller is obtained. The fuzzy state feedback gains are derived by solving
pertinent LMIs. The proposed method can avoid restrictions on the derivative
of the time-varying delay assumed in previous works. The effectiveness of our
method is demonstrated by a numerical example.

Keywords

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