A new and effective controller for Inductor Motor drives using Direct-Decoupling Methodology based on exact linearization algorithm and adaptive back stepping technology

Control of Inductor Motors is a difficult task because of the motors´ non-linear nature. Hence, the Inductor Motors are usually expressed by complicated non-linear models. This paper presents a new and effective method for modeling stator current and estimating rotor flux of an induction motor by applying Direct-Decoupling Methodology. A nonlinear control approach with full state feedback linearization has been used to construct the decoupling form of the induction motors. A new current controller named “direct-decoupling”, based on exact linearization algorithm of the motor current model has been proposed. The obtained linear system in a new state-space is very convenient to design the current controller and the rotor flux estimator for induction motors. A linear Kalman filter has also been derived to construct an observer for rotor flux. Effectiveness of the new adaptive backstepping controller for induction motors and Kalman filter for observation of rotor flux has been verified by simulations and experiments in wide ranges of motor speed. Simulations and experiment results show clearly that the rotor flux can be well estimated in all operating conditions and performance of induction motors under all dynamic modes can be improved by using the new developed controller.