Adaptive nonlinear control of induction motors with flux observer

In this paper we present an adaptive nonlinear speed control algorithm for induction motors. Input-output linearisation techniques are used to track torque and rotor flux and the scheme is extended for speed control. The adaptation, based on Lyapunov-design can cope with rotor and stator resistance variations while preserving stability. Exact current limitation is achieved in the known parameter case. The use of a Kalman filter, relaxes the need of rotor flux measurement. In this case no global stability proof is available. Finally only few modifications are needed for the implementation of a sampled version of the algorithm. These features are confirmed by significant simulations, that emphasise the effects of the adaptation and the observer as well as the interest of the current limitation