Sensorless PMSM Control for Automobile Air-Condition Based on Sliding Mode Observer

The paper presents a review of the sensorless position estimation algorithms which are being adopted by Automobile Air-condition. After analyzing and introducing of the sliding mode variable structure theory and the mathematic model of PMSM, the control strategy based on SMO and its math expression are presented. The simulation model in MATLAB/SIMULINK is established, in which the real rotor position and the estimated rotor position calculated by SMO under dynamic and static state are analyzed. Besides, the principle of sliding gain selection is raised. The simulation provides the theoretical foundation.