A relaxed stability analysis of T-S fuzzy system

Stability conditions of T-S fuzzy system based on a common positive definite matrix or a set of positive definite matrices have been proposed in lots of literature. This paper proposes an approach to relax the conservatism of those stability conditions. By using the concept of the efficient maximal overlapped-rules group (EMORG), a relaxed sufficient condition is derived to guarantee quadratic stability of the fuzzy model globally. This condition only requires finding a local common positive definite matrix in each EMORG. Moreover, the proposed stability condition includes previous results as special cases. Several examples are illustrated to show the effectiveness of the proposed stability condition.