Non-conservative output feedback controller for discrete systems with actuator saturation

ZHAO Xiao-dong， FENG Hui-hui
（Institute of Information and Control， Hangzhou Dianzi University， Hangzhou 310018， China）

Abstract： Aiming at solving the problems of conservative output feedback controller design for discrete systems with saturated input，convex polyhedra analysis method was applied to the system in the description of the attractive regions in terms of system states. Controllable region description form was given and the relationship between output feedback and controllable region was investigated. Due to the reason that none control action was applied to first step control of anti-stable system，the controllable region was greatly decreased and the conservatism of the system was caused. For second order anti-stable system，specific forms of the first step of the output feedback controller were proposed based on system output matrix and the initial values of output. Under this controller，the controllable region was maximized and the conservation was decreased in significant ways. Simulation examples were given using Matlab. The results indicate that the proposed method is valid．
Key words： input saturation discrete system； output feedback controller； second order systems