Improved observer-based Hoo control for fuzzy interconnected systems

In this paper, based on Lyapunov-Krasovskii functional approach and the decentralized control theory of interconnected systems, we consider the observer-based control design for a class of fuzzy descriptor interconnected systems. Firstly, the stability conditions of the T-S fuzzy model with a prescribed performance level are provided in theorem 1, but there is no efficient algorithm solving the inequalities. Theorem 2 proposes a single-step method, reducing the conservatism of the conditions. This method overcomes the drawback of the two-step approach in other methods. The stability conditions in theorem 1 are the sufficient and necessary conditions of the ones in theorem 2. The parameters of reliable H^∞ controllers can be found via LMI toolbox in MATLAB software. Finally a numerical example is given to show the validity of the proposed method.