Backstepping control for an induction motor using an adaptive sliding rotor-flux observer

This paper deals with the synthesis of a speed and flux control strategy for an induction motor drive based on an output feedback adaptive backstepping controller. The proposed strategy is asymptotically stable in the context of Lyapunov theory. The adaptive backstepping method takes into account the nonlinearities of the system in the design control law. The unavailable rotor flux is recovered by using an adaptive sliding rotor-flux observer provided with an adaptive mechanism of rotor resistance. Simulated and experimental results on a 1.5-kW squirrel-cage induction motor drive are displayed to validate the feasibility and the effectiveness of the proposed strategy.

► We have proposed a new nonlinear control algorithm based on the backstepping approach for an induction motor drive.
► A new adaptive sliding-mode-observer with online rotor resistance adaptation approach is developed.
► The rotor time-constant is estimated based on the Lyapunov stability theory.
► The developed control scheme has been implemented using a digital signal processor board.