Finite-dimensional control of linear discrete-time fractional-order systems

• Type: Article in International Scientific Journal
• Date: 2020

Authors

Alessandretti, A (Author) Other; Pequito, S (Author) Other; Pappas, GJ (Author) Other; Aguiar, AP (Author) FEUP

Journal

Title: Automatica

Vol. 115

ISSN: 0005-1098

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 1 Citation

Scopus - 1 Citation

Other information

Authenticus ID: P-00R-QFV

DOI: 10.1016/j.automatica.2019.108512

Abstract (EN): This paper addresses the design of finite-dimensional feedback control laws for linear discrete-time fractional-order systems with additive state disturbance. A set of sufficient conditions are provided to guarantee convergence of the state trajectories to an ultimate bound around the origin with size increasing with the magnitude of the disturbances. Performing a suitable change of coordinates, the latter result can be used to design a controller that is able to track reference trajectories that are solutions of the unperturbed fractional-order system. To overcome the challenges associated with the generation of such solutions, we address the practical case where the references to be tracked are generated as a solution of a specific finite-dimensional approximation of the original fractional-order system. In this case, the tracking error trajectory is driven to an asymptotic bound that is increasing with the magnitude of the disturbances and decreases with the increment in the accuracy of the approximation. The proposed controllers are finite-dimensional, in the sense that the computation of the control input only requires a finite number of previous state and input vectors of the system. Numerical simulations illustrate the proposed design methods in different scenarios. (C) 2019 Published by Elsevier Ltd.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 9