Further results on stability analysis of T-S fuzzy systems with time-varying delay

This paper investigates the stability problem of Takagi-Sugeno (T-S) fuzzy systems with time-varying delay. Different from some existing methods, a new delay-productdependent Lyapunov-Krasovkii functional (LKF) is proposed, whose derivative is estimated by using the proposed cubic function negative-determination lemma (NDL). Moreover, a parameter-dependent reciprocally convex inequality (PDRCI) is proposed to improve the estimation accuracy of reciprocally convex terms. Besides, an improved cubic function NDL is derived to solve the negative-definiteness determination of cubic functions. Based on the proposed delay-product-dependent LKF, the developed PDRCI and the improved cubic function NDL, a less conservative stability criterion is obtained. Three examples are presented to demonstrate the merits of the proposed approaches by comparing with several existing results.