Sliding-Mode MRAS based Encoderless Predictive Torque Control for Induction Machine

Abstract

This paper presents a sliding-mode (SM) model reference adaptive system (MRAS) observer for predictive torque control (PTC) in the induction machine drives. The PTC scheme is one of the most promising control strategy for electrical drives. However, its performance is constrained due to the accuracy of parameter and speed estimation. The proposed SM MRAS is employed to estimate rotor speed for PTC. The dominant feature of the methodology is that the adjustable model is modified by a sliding manifold in accordance with the error signal. Compared with conventional MRAS, the proposed method is more robust and easily tuned. To enhance robustness of the PTC scheme to the parameter variation, the extended rotor resistance compensation is employed in the estimator. In this paper, the experimental results confirm that the proposed method achieves fast dynamic performance and strong robustness.