A Digital Segmented Repetitive Control Algorithm

This paper presents the structure and analysis of the segmented discrete-time repetitive controller. The repetitive controller is designed to reject periodic disturbance and/or track periodic reference signal with known period. Resulted from the Internal Model Principle, the repetitive control law is applied to the entire control path. However, when crucial segments within a control path are of concern, the segmented repetitive control law, which applies control actions only to those segments, can be utilized to save the memory space. It is shown that such a segmented repetitive control system is stable if the original nonsegmented one is stable.