Technical note: On the actuator rate limit effect in reaction curves

Jie Yuan; Shumin Fei; YangQuan Chen

doi:10.1016/j.isatra.2021.01.061

Technical note: On the actuator rate limit effect in reaction curves

ISA Trans. 2021 Nov:117:303-308. doi: 10.1016/j.isatra.2021.01.061. Epub 2021 Feb 6.

Authors

Jie Yuan¹, Shumin Fei², YangQuan Chen³

Affiliations

¹ Key Laboratory of Measurement and Control of CSE, Ministry of Education, School of Automation, Southeast University, Nanjing 210096, China; Mechatronics, Embedded Systems and Automation Lab, University of California, Merced, CA 95343, USA. Electronic address: jieyuanseu@seu.edu.cn.
² Key Laboratory of Measurement and Control of CSE, Ministry of Education, School of Automation, Southeast University, Nanjing 210096, China. Electronic address: smfei@seu.edu.cn.
³ Mechatronics, Embedded Systems and Automation Lab, University of California, Merced, CA 95343, USA. Electronic address: ychen53@ucmerced.edu.

PMID: 33593485
DOI: 10.1016/j.isatra.2021.01.061

Abstract

While actuator rate limit is common and counted in practical engineering, it has not drawn enough attention in control synthesis especially system identification. In this note, it aims to construct a new identification framework for first-order plus time-delay (FOPTD) systems affected by actuator rate limit. It is found that the rate limit can lead to an illusory delay in system reaction curves. Furthermore, necessary quantitative analyses are given to validate that excessively estimated or illusory delay significantly influences estimation accuracy of other parameters and subsequently degrades control performance. Two illustrative examples and experimental results are provided to demonstrate the adverse effect of actuator rate limit on system identification and the effectiveness of the proposed model structure on control performance.

Keywords: Actuator rate limit; Delay; First-order plus time-delay system; Reaction curve; System identification.