Global robust disturbance attenuation and almost disturbance decoupling for uncertain cascaded nonlinear systems

• Published in: Automatica (Oxford) Vol. 35; no. 4; pp. 697 - 707
• Main Authors: Su, Weizhou, Xie, Lihua, de Souza, Carlos E.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 1999; Elsevier
• Subjects: [formula omitted] control; [formula omitted]-gain; Applied sciences; Computer science; control theory; systems; Control system synthesis; Control theory. Systems; Disturbance decoupling; Exact sciences and technology; Nonlinear systems; Robust control; Robust control; L 2 -gain; H ∞ control; Disturbance decoupling; Nonlinear systems; State feedback; Disturbance rejection; Uncertain system; Control system; H infinite control; Lyapunov method; Recursive method; System design; System synthesis; Non linear system; Non minimum phase system
• ISSN: 0005-1098; 1873-2836
• DOI: 10.1016/S0005-1098(98)00200-3

This paper studies the problem of global robust H ∞ disturbance attenuation for a class of non-minimum-phase nonlinear systems subject to parameter uncertainty. The problem addressed is the design of a state feedback controller such that the closed-loop system is input-to-state stable and the L 2 -gain from the disturbance input to the controlled output is not larger than a prescribed value for all admissible parameter uncertainties. A recursive Lyapunov-based design approach is developed to construct the controller explicitly. The problem of global robust H ∞ almost disturbance decoupling, where the level of disturbance attenuation can be made arbitrarily small for all allowed uncertainties, is also addressed.