Matched Disturbance Rejection for a Class of Nonlinear Systems

Title: Matched Disturbance Rejection for a Class of Nonlinear Systems
Creator: Ferguson, Joel; Donaire, Alejandro; Ortega, Romeo; Middleton, Richard H.
Relation: IEEE Transactions on Automatic Control Vol. 65, Issue 4, p. 1710-1715
Publisher Link: http://dx.doi.org/10.1109/TAC.2019.2933398
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Resource Type: journal article
Date: 2020
Description: In this paper, we present a method to robustify asymptotically stable nonlinear systems by adding an integral action that rejects unknown additive disturbances. The proposed approach uses a port-Hamiltonian (pH) representation of the open-loop dynamics, which, relying on the asymptotic stability property, is guaranteed to exist. The integral action controller preserves the pH structure, and, by adding a suitable cross term between the plant and the controller states to the closed-loop energy function, it avoids the unnatural coordinate transformation used in the past. The controller is shown to be robust against some common types of modeling uncertainty, including unknown friction dynamics in mechanical systems.
Subject: integral control; Lyapunov methods; nonlinear control systems; Port-Hamiltonian systems
Identifier: http://hdl.handle.net/1959.13/1438840
Identifier: uon:40739
Identifier: ISSN:0018-9286
Language: eng
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