IMC-based PID control of servo motors with extended state observer. (October 2019)

• Record Type: Journal Article
• Authors: Li, Ping; Zhu, Guoli
• Is Part Of: Mechatronics. Volume 62(2019)
• Publication Date: 2019-10
• Subjects: Disturbances -- Extended state observer (ESO) -- Internal model control (IMC) -- PID controller -- Servo motor -- Uncertainties; Computer integrated manufacturing systems -- Periodicals; Flexible manufacturing systems -- Periodicals; Mechatronics -- Periodicals; Productique -- Périodiques; Fabrication, Systèmes flexibles de -- Périodiques; Mécatronique -- Périodiques; Computer integrated manufacturing systems; Flexible manufacturing systems; Mechatronics; Periodicals; 629.89
• DOI: 10.1016/j.mechatronics.2019.102252
• Languages: English
• ISSNs: 0957-4158

Abstract

Highlights: Servo motor system are subject to uncertainties and/or disturbances. Internal model control (IMC) scheme specifies the tracking performance. Extended state observer (ESO) enhances the resistance to disturbances. 2-degree-of-freedom IMC-PID controller with ESO is synthesized to improve the control performance. The order reduction technique simplifies the analysis of the tracking error dynamics. Abstract: In this paper, a simple and effective internal model control (IMC) with extended state observer (ESO) is presented for the position tracking control of servo motors perturbed by uncertainties and disturbances. Firstly, a linear feedback controller is directly derived from the standard IMC principle for a prescribed tracking performance. Then, a linear ESO is introduced into the IMC-based controller for active disturbance rejection control (ADRC). However, for the ESO with a limited bandwidth, there will exist state estimation errors, which limit the tracking accuracy. To overcome this drawback, 2-degree-of-freedom IMC-based PID controller with ESO is developed for further improvement of the control accuracy. The dynamics of the tracking error is analyzed based on an order reduction technique and the ultimately bounded stability of the control system can be guaranteed. Since the IMC scheme and the ESO can be designed separately and integrated effectively to attenuate the effect of disturbances, a simple, effective and intuitive framework can be given for the analysis and synthesis of the motion control system. Finally, the effectiveness of this novel control approach is validated by comparative simulations and experiments implemented on a practical servo motor system.