On Integrating Uncertainty Estimator Into PI Control for a Class of Nonlinear Uncertain Systems

• 成果类型: Article
• 署名作者: Xue, Wenchao; Chen, Sen; Zhao, Cheng; Huang, Yi; Su, Jianbo
• 署名单位: Chinese Academy of Sciences; Academy of Mathematics & System Sciences, CAS; Chinese Academy of Sciences; University of Chinese Academy of Sciences, CAS; Shaanxi Normal University; Shandong University; Shanghai Jiao Tong University
• 刊物名称: IEEE TRANSACTIONS ON AUTOMATIC CONTROL
• ISSN/ISSBN: 0018-9286
• DOI: 10.1109/TAC.2020.3024475
• 发表日期: 2021
• 页码: 3409-3416
• 关键词: Active disturbance rejection control (ADRC); disturbance estimation and rejection; extended state observer (ESO); nonlinear uncertain dynamical systems; PI control; tuning laws

摘要

Proportional-integral (PI) control/loop has been widely used in numerous industrial processes. This article focuses on integrating uncertainty estimator into PI controller for better robustness and transient performance against uncertain nonlinear coupling dynamics and time-varying disturbances. First, the descriptions for the sizes of three kinds of uncertainties in a class of multi-input-multi-output nonlinear systems are discussed. Then, the tuning laws of the typical uncertainty estimator, i.e., extended state observer (ESO), are quantitatively presented to ensure the stability of closed-loop systems. More importantly, it is shown that the desired transient performance of tracking error can be ensured by tuning the bandwidth of ESO. In addition, it is proven that much stronger disturbance rejection at low frequency can be achieved by integrating the uncertainty estimator module. The simulation results for calibration-free robotic eye-hand coordination system show the effectiveness of the proposed method.