A hybrid sliding mode flux observer for induction motor drive

This paper proposes a rotor flux estimation method based on high-order sliding mode and non-singular terminal sliding mode method for realizing field orientation control of an induction motor. A nonsingular terminal sliding mode control is utilized to improve the response speed and tracking precision of the observer. Meanwhile, high-order sliding mode technique is adopted to eliminate the chattering phenomenon so that the control signals of observer can be used directly for estimating the flux of the induction motor. The proposed method improves the robustness of the flux observer for induction motors. The stability of the proposed observer is analyzed. The simulation results demonstrate that the proposed method can converge to actual value quickly with high precision and is insensitive to parameters variations.