Design and real-time implementation of a robust fractional second-order sliding mode control for an electromechanical system comprising uncertainties and disturbances

Abstract

The present article evaluates the design, analysis, and implementation of a novel fractional second-order sliding mode control scheme for an uncertain second-order system. The developed controller comprises a fractional-order proportional integral derivative sliding surface. The closed-loop stability analysis is performed by using the Lyapunov theorem. The proposed equivalent and switching control signals have been mathematically evaluated at various scenarios comprising uncertainties and disturbances. Several simulations are investigated by including model uncertainties, measurement noises, and disturbances. In addition, various real-time experiments are conducted with different operating conditions. To this end, a real-time reduced-order approximated model of an electromechanical system is constructed. The controller performance has been compared with a number of control techniques to illustrate the promising features of the proposed fractional-order controller. It can be reported that the transient response of the system, control signals applicability, and disturbance rejection capability are quite satisfactory when compared to recently presented control schemes. As a consequence, it is evident that the control scheme has the ability to reduce the chattering phenomenon and increase the system’s robustness.

Keywords

• Fractional-order control
• Robustness
• High-order sliding mode control
• Electromechanical system
• Experimental application