Nonlinear Speed Control of Induction Motor by the Combination of Fuzzy-Sliding-Mode and Integral-Backstepping Controllers

This paper treats a nonlinear control technique applied to the three-phase induction motor speed, by using a hybrid regulator combines between Backstepping and sliding mode techniques. The idea stems from the observation that the integral-Backstepping offers a total external disturbance rejection, but it can cause a remarkable overshoot at startup because of the integral action, the thing that does not exist in the sliding mode controller. However, it has a major disadvantage presented by very high-frequency oscillations in the control signals during the steady state. The proposed solution is to use a powerful supervisor that can combine the benefits of both controllers, without lacking its efficiencies. The supervisor can give a decision through an approximate information on the operating regime. Which makes it possible to activate the sliding mode in the transient regime, while the Backstepping drives control in the steady-state. This approach has been analyzed and verified by simulation to illustrate the performance of the proposed controller.