A robust and new simple control strategy for a class of nonlinear power systems: induction and servomotors

Abstract

In this paper, a robust backstepping controller is presented for position tracking of a class of servomotors. It has been shown by mathematical proof that the closed-loop system with the proposed controller has global asymptotic stability in the presence of structured and unstructured uncertainties, and external disturbances. In the following sections of this paper, to remove the undesirable phenomenon of chattering in the proposed control input, using a Takagi-Sugeno-Kang fuzzy system a robust fuzzy backstepping controller is designed that does not suffer from the undesirable phenomenon of chattering. To investigate the performance of the proposed controller, an induction motor and a DC motor with uncertainties are used as case studies. In the simulation phase, to provide essential challenges for the proposed controllers, simulations have been implemented in two steps. The results of these simulations show that the proposed approaches are very robust in the presence of parametric uncertainties, especially in the presence of external disturbances. In the design of a robust fuzzy controller, practical implementation considerations are taken into account in a way where the control input has a low computational burden.