A Spectral Analysis of Feedback Regulation Near and Beyond Nyquist Frequency
A Spectral Analysis of Feedback Regulation Near and Beyond Nyquist Frequency
复制标题
DOI：
10.1109/tmech.2018.2795960
复制
发表时间：
2018-01
期刊：
影响因子：
--
通讯作者：
Dan Wang;Xu Chen
中科院分区：
文献类型：
--
作者：
Dan Wang;Xu Chen
采样数据控制中的一个基本挑战出现时，连续时间工厂受到干扰，具有显着的频率分量超过反馈传感器的奈奎斯特频率。这种固有的困难为现代和新兴技术中的快速高性能控制创造了巨大的障碍，例如增材制造和视觉伺服，其中传感器的更新速度与工厂的动态相比较低。本文分析了这种情况下的闭环信号的频谱特性，重点是机电系统。我们提出了一种频谱分析方法，提供了新的理解的时间和频率域采样数据的性能。沿着的过程中发现的频谱细节，在这种超越奈奎斯特控制，我们还报告了一个基本的理解，单速率高增益反馈，以拒绝干扰不仅超出，而且低于奈奎斯特频率的不可行性。新的指标和工具，然后提出系统地量化性能的限制。验证和实际影响的局限性提供了一个精密镜振镜平台上进行激光扫描的实验案例研究。
A fundamental challenge in sampled-data control arises when a continuous-time plant is subject to disturbances that possess significant frequency components beyond the Nyquist frequency of the feedback sensor. Such intrinsic difficulties create formidable barriers for fast high-performance controls in modern and emerging technologies such as additive manufacturing and vision servo, where the update speed of sensors is low compared with the dynamics of the plant. This paper analyzes spectral properties of closed-loop signals under such scenarios, with a focus on mechatronic systems. We propose a spectral analysis method that provides new understanding of the time- and frequency-domain sampled-data performance. Along the course of uncovering spectral details in such beyond-Nyquist controls, we also report a fundamental understanding on the infeasibility of single-rate high-gain feedback to reject disturbances not only beyond but also below the Nyquist frequency. New metrics and tools are then proposed to systematically quantify the limit of performance. Validation and practical implications of the limitations are provided with experimental case studies performed on a precision mirror galvanometer platform for laser scanning.