Novel robust observer-controller synthesis method for Takagi-Sugeno systems

For the output feedback control problem of a T-S fuzzy system, an H-infinity observer-controller synthesis method is proposed. First, with parallel distributed compensation fuzzy observer and controller, an augmented error system is obtained. Based on Lyapunov function approaches, system stability and robust conditions are achieved. Then, by dividing the non-convex conditions into observer-dominant and controller dominant parts, the conditions are converted into convex form to facilitate the numerical solving process. Also, input saturation and system measurement disturbance are considered in the synthesis procedure. Finally, a numerical and a vessel control example are adopted to make comparisons with existing methods, with the results clearly showing the conservatism reduction effects and good control performance of the proposed method.

Automated summary

An H-infinity observer-controller synthesis method is proposed for the output feedback control problem of a T-S fuzzy system. The method achieves system stability and robust conditions using parallel distributed compensation fuzzy observer and controller. By converting non-convex conditions into convex form, the approach facilitates numerical solving process and considers input saturation and system measurement disturbance for better control performance. The results from numerical and vessel control examples demonstrate the conservatism reduction effects and good control performance of the proposed method.