Fixed-time anti-disturbance control for systems with multiple disturbances

The anti-disturbance control problem is investigated for systems with multiple disturbances. For the disturbance with partially known information, an observer was designed to give the online estimation. Based on which, a fixed-time anti-disturbance control scheme was proposed by combing regional pole placement, the H∞ control method and fixed-time stability theory. The proposed controller can make the closed-loop system globally stable in fixed time, which has the advantages of high control accuracy, fast convergence speed, and the convergence time is independent of the initial conditions. Finally, two simulation examples including a numerical example and a doubly fed induction generators system are provided to show the effectiveness of the proposed method.