An analysis and design method for actuator saturation linear systems with disturbance

In this paper, the set invariance condition and disturbance rejection problem of actuator saturation linear systems with disturbance are discussed. Under the control of linear state feedback, the new set invariance condition and new optimal approach to enlarge the invariant ellipsoid are given by using composite quadratic Lyapunov functions method. It is proved that the convex hull of some invariant ellipsoids is also an invariant set, and a state feedback control law is constructed to achieve disturbance rejection for closed systems. Finally, the effectiveness of set invariance condition and disturbance rejection method is demonstrated by an example.