In many real-world rotary machines, there is an inherent need to attenuate time-varying but position-dependent periodic disturbances. This article proposes an improved repetitive controller, in which a spatial internal model, a spatial low-pass filter, and a frequency alignment are synthesized. The controller is digitally implemented in a uniform time-sampling system. Specifically, a universal internal model of arbitrary periodic signal in spatial domain is derived for the attenuation of the position-dependent disturbances in the rotary machine, and a spatial low-pass filter is designed for the stability of the closed-loop system. Furthermore, a frequency alignment strategy is designed to compensate the bias resulted from the filter. Moreover, the cascaded utilization of the proposed controllers is introduced to improve the performance of a position-feedback servo system. Experimental verification and comparisons validate the feasibility and effectiveness of the proposed method in both single and cascaded configurations.

中文翻译：

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通过频率对准的改进空间重复控制来减轻旋转机械的位置相关周期性扰动

在许多现实世界的旋转机械中，固有地需要衰减随时间变化但与位置有关的周期性干扰。本文提出了一种改进的重复控制器，其中合成了空间内部模型，空间低通滤波器和频率对准。控制器在统一的时间采样系统中以数字方式实现。具体而言，推导了空间域中任意周期信号的通用内部模型，用于衰减旋转电机中与位置有关的干扰，并设计了空间低通滤波器以实现闭环系统的稳定性。此外，设计了一种频率对准策略来补偿由滤波器引起的偏置。此外，为了提高位置反馈伺服系统的性能，引入了所建议控制器的级联利用。实验验证和比较验证了该方法在单配置和级联配置中的可行性和有效性。