Absolute Stability for a Class of Takagi-Sugeno Fuzzy Control Systems

In this paper, we presented a sufficient condition on the frequency domain for the absolutely stable analysis of the Takagi-Sugeno (T-S) fuzzy control system. For modeling the plant and controller we used transfer functions instead of the state description and showed that the overall T-S fuzzy plant is a polytope of transfer functions. Besides, by applying local proportional controllers, the bounds of proportional parameter of the overall fuzzy controller can be computed. Hence the robust absolutely stability criterions with graphical interpretation for closed-loop T-S fuzzy control system were derived.