A Design Method of Simple Multi-Period Repetitive Controllers for Time-Delay Plants

The multi-period repetitive control system is a type of servomechanism for periodic reference input. Even if the plant does not include time-delay, the transfer function from the reference input to the output and that from the disturbance to the output of the multi-period repetitive control system generally have an infinite number of poles. In order to specify the input-output characteristic and the disturbance attenuation characteristic easily, the concept of simple multi-period repetitive control systems such that the controller works as a stabilizing multi-period repetitive controller and the transfer function from the reference input to the output and that from the disturbance to the output have a finite number of poles is presented by Yamada and Takenaga. However, the method by Yamada and Takenaga cannot apply for time-delay plants. In this paper, we propose a design method for simple multi-period repetitive controllers for time-delay plants.