This paper deals with the design of an advanced control law by backstepping with an observer for a special class of nonlinear systems. We design an observer with a single adjustment gain as a function of speed. Our contribution is developed by demonstrating a nonlinear control law by backstepping using the global Lyapunov stability of the controller, the nonlinear observer and the induction motor. We study the behavior of the torque tracking and the rotor flux of the induction motor in the natural frame(α,β). The control algorithm obtained is studied through simulations and applied in many configurations (flux and speed and torque disturbances), and is shown to be very efficient.
