The optimal sequence for reset controllers

TL;DR

This paper identifies the optimal arrangement of reset and linear parts in reset controllers using high order sinusoidal input describing functions, leading to improved precision and control input in high-tech applications.

Contribution

It introduces a method to determine the optimal sequence of controller parts, enhancing reset controller performance over traditional arrangements.

Findings

Optimal sequence improves system precision

Enhanced control input achieved

Experimental validation confirms theoretical results

Abstract

PID controllers cannot satisfy the high performance requirements since they are restricted by the water-bed effect. Thus, the need for a better alternative to linear PID controllers increases due to the rising demands of the high-tech industry. This has led many researchers to explore nonlinear controllers like reset control. Although reset controllers have been widely used to overcome the limitations of linear controllers in literature, the performance of the system varies depending on the relative sequence of controller linear and nonlinear parts. In this paper, the optimal sequence is found using high order sinusoidal input describing functions (HOSIDF). By arranging controller parts according to this strategy, better performance in the sense of precision and control input is achieved. The performance of the proposed sequence is validated on a precision positioning setup. The experimental results demonstrate that the optimal sequence found in theory outperforms other sequences.