Disturbance compensation for time-delay processes

In this paper, a general control scheme for disturbance rejection is presented. It is an extension of the disturbance observer used in mechatronics, and made applicable to time-delay processes. It is shown that the proposed control scheme can achieve better load response in general and reject periodic disturbance asymptotically in particular. Stability analysis and disturbance rejection performance are provided. Simulation results confirm that the proposed method yields superior load response compared to the classical feedback system.