On convergence of non-linear extended state observer for multi-input multi-output systems with uncertainty

• Published in: IET control theory & applications Vol. 6; no. 15; pp. 2375 - 2386
• Main Authors: GUO, B.-Z, ZHAO, Z.-L
• Format: Journal Article
• Language: English
• Published: Stevenage Institution of Engineering and Technology 01.10.2012; John Wiley & Sons, Inc
• Subjects: Applied sciences; Computer science; control theory; systems; Control theory. Systems; Convergence; D.c. Machines; Electrical engineering. Electrical power engineering; Electrical machines; Exact sciences and technology; Modelling and identification; MIMO system; Disturbance rejection; Non linear control; Non linear function; Permanent magnet motors; Non linear system; Synchronous motor; Non linear stability; Current control; Uncertain system; System identification; Dc motor; State estimation; Non linear observer
• ISSN: 1751-8644; 1751-8652
• DOI: 10.1049/iet-cta.2012.0123

In this study, the convergence of non-linear extended state observer (ESO) for a class of multi-input multi-output non-linear systems with uncertainty is studied. The unknown part that comes from either the system itself or the external disturbance is considered as an augmented state. The state variable and augmented state are estimated simultaneously through the ESO. It is shown that with the pertinent choice of non-linear functions for observer, the error between the state and observer can be as small as desired when the high-gain tuning parameter is sufficiently small. The current control for permanent-magnet synchronous motor is applied. [PUBLICATION ABSTRACT]