Fuzzy dynamic output feedback H∞ control for continuous-time T-S fuzzy systems under imperfect premise matching

This paper addresses a fuzzy dynamic output feedback H-infinity control design problem for continuous time nonlinear systems via T-S fuzzy model. The stability of the fuzzy closed-loop system which is formed by a T-S fuzzy model and a fuzzy dynamic output feedback H-infinity controller connected in a closed loop is investigated with Lyapunov stability theory. The proposed fuzzy controller does not share the same membership functions and number of rules with T-S fuzzy systems, which can enhance design flexibility. A line-integral fuzzy Lyapunov function is utilized to derive the stability conditions in the form of linear matrix inequalities (LMIs). The boundary information of membership functions is considered in the stability analysis to reduce the conservativeness of the imperfect premise matching design technique. Two simulation examples are provided to demonstrate the effectiveness of the proposed approach. (C) 2017 ISA. Published by Elsevier Ltd. All rights reserved.