An adaptive robust position control for induction machines using a sliding mode flux observer

An adaptive sliding-mode position control for induction motors using the field oriented control theory is presented. The proposed sliding-mode control law incorporates an adaptive switching gain to avoid calculating an upper limit for the system uncertainties. The design also incorporates a sliding-mode flux estimator that operates on the principle of flux and current observer. The proposed observer uses a plant model and also includes a sliding mode terms to overcome the model uncertainties. The stability analysis of the proposed observer and controller under parameter uncertainties and load disturbances is provided using the Lyapunov stability theory. Finally experimental results show that the proposed controller with the proposed observer provides high-performance dynamic characteristics and that this control scheme is robust with respect to plant parameter variations and external load disturbances.