A new fractional-order sliding mode controller via a nonlinear disturbance observer for a class of dynamical systems with mismatched disturbances.
This paper investigates the stabilization and disturbance rejection for a class of fractional-order nonlinear dynamical systems with mismatched disturbances. To fulfill this purpose a new fractional-order sliding mode control (FOSMC) based on a nonlinear disturbance observer is proposed. In order to design the suitable fractional-order sliding mode controller, a proper switching surface is introduced. Afterward, by using the sliding mode theory and Lyapunov stability theory, a robust fractional-order control law via a nonlinear disturbance observer is proposed to assure the existence of the sliding motion in finite time. The proposed fractional-order sliding mode controller exposes better control performance, ensures fast and robust stability of the closed-loop system, eliminates the disturbances and diminishes the chattering problem. Finally, the effectiveness of the proposed fractional-order controller is depicted via numerical simulation results of practical example and is compared with some other controllers.
Faculty of Electrical and Computer Engineering University of Tabriz, Tabriz, Iran. Electronic address: sh.pashaei92@ms.tabrizu.ac.ir.
Shabnam
S
Pashaei
Faculty of Electrical and Computer Engineering University of Tabriz, Tabriz, Iran. Electronic address: mbadamchi@tabrizu.ac.ir.
Mohammadali
M
Badamchizadeh
Disturbance observer; Fractional calculus; Fractional-order mismatched uncertain systems; Lyapunov stability theory; Sliding mode control