On the synthesis of a stable and causal compensator for discrete-time high-order repetitive control systems

Abstract

This paper presents a novel methodology to design a discrete-time compensator for a high-order repetitive control system. An optimization-based approach is applied to design the compensator, which is required to be stable and causal. This methodology is applicable to both minimum and non-minimum phase systems, for which stability and tracking error convergence are ensured. The compensator is yielded in the form of a proper transfer function and can be implemented separately without being merged with a high-order internal model. The high-order internal model is used to provide robustness against period variations of the reference signal. Simulation and experimental results are provided to show the effectiveness of the compensator design methodology.