First‐order plus time‐delay systems under the effects of actuator rate limit. Issue 17 (1st October 2020)

• Record Type: Journal Article
• Authors: Yuan, Jie; Han, Jie; Chai, Lin; Fei, Shumin; Chen, Yang Quan
• Is Part Of: IET control theory & applications. Volume 14:Issue 17(2020)
• Page Start: 2481
• Page End: 2490
• Publication Date: 2020-10-01
• Subjects: actuators -- sensitivity analysis -- delays -- parameter estimation -- delay systems -- curve fitting -- control system synthesis; actuator rate limit effect whose limit value -- parameter mismatch -- parameter sensitivity analyses -- rate limit value -- time‐delay systems -- actuator rate limit phenomenon -- control systems -- practical engineering -- system identification -- step function -- parameter estimation -- first‐order derivative -- step time -- actuators -- system response speed -- parameter identification -- controller design -- control performance -- graphical method -- curve fitting method; Control theory -- Periodicals; Automatic control -- Periodicals; 629.8312
• DOI: 10.1049/iet-cta.2019.1110
• Languages: English
• ISSNs: 1751-8644

Abstract

Abstract : Actuator rate limit phenomenon is ubiquitous in control systems, but it has always been neglected in practical engineering. Especially, few papers are published to investigate the system identification while considering the rate limit. Step function is commonly used in parameter estimation and its first‐order derivative at the step time goes to infinity, which is not affordable by real actuators. As a result, the rate limit slows down the system response speed, misleads the parameter identification, and subsequently affects the controller design and deteriorates the control performance. This study proposes both graphical method and curve fitting method to identify the first‐order plus time‐delay (FOPTD) systems with consideration of the actuator rate limit effect whose limit value is unknown. Quantitative analyses of the parameter mismatch in the traditional FOPTD model and parameter sensitivity analyses are also carried out. Both simulation results and experimental results have shown the necessity and feasibility of defining a new model structure which includes the rate limit value.