Robust stability analysis and disturbance rejection for discrete-time systems with constraints

This paper addresses the problem of stability analysis and disturbance rejection for uncertain discrete-time systems in the presence of actuator saturation and exogenous disturbance. A newly defined saturation-dependent Lyapunov function is used to estimate the domain of attraction, and a constrained LMI optimization problem is formulated. Algorithms are developed to estimate the maximal norm of the exogenous disturbance that can be tolerated by systems. Furthermore upper bound of regional L₂ gain for exogenous disturbance is minimized. Numerical examples are presented to show the effectiveness of the proposed method compared with the method before