Correction of Rotor Position Estimation Error for High-Speed Permanent Magnet Synchronous Motor Sensorless Drive System Based on Minimum-Current-Tracking Method

This article focuses on the issue of the rotor position estimation error correction for high-speed permanent magnet synchronous motor sensorless drive system. First, a rotor position estimator is designed. Then the estimation error caused by different kinds of nonideal factors is analyzed in detail. Estimation error results in larger amplitude of the stator current, the larger loss, and the degradation of the output torque. To eliminate the estimation error, a novel correction method based on the "minimu-current-tracking (MCT)" method is proposed in this article. The main idea of the proposed method is to obtain the minimum amplitude of the stator current adaptively through the MCT algorithm. The estimation error can be reduced to zero by correcting the compensation factor of the designed position estimator and observing the amplitude of stator current until the amplitude converges to the minimum value. The proposed method has two advantages: 1) the estimation error caused by no matter which kind of nonideal factor can be completely corrected; 2) no sensitive parameters are required in the proposed method. Finally, sufficient simulated results and experimental results verify the effectiveness of the proposed MCT-based method.