A Parallel Peak Filter with Time-Delay Compensation for Multi-Frequency Disturbance Rejections Beyond Control Bandwidth

This paper proposes parallel peak filters to reject multi-frequency disturbances beyond the baseline feedback control bandwidth, which is restricted by time delays of the sample-data control system. Supplementing the baseline feedback control with parallel peak filters has an extremely simple control structure. In addition, a time-delay compensation method is proposed to eliminate the adverse effect of time delay on the designing parallel peak filters. Such deign break through the bandwidth limitation of baseline feedback control and provide a new idea for disturbance rejection beyond the bandwidth. Furthermore, multiple parallel peak filters with time-delay compensation provide multi-frequency disturbance rejection, and each parallel peak filter is independent of each other. Experiments are conducted in an image-based stabilization system, and the experimental results demonstrate that the proposed method can enhance multi-frequency disturbance rejection beyond the baseline feedback control bandwidth in time-delay systems.