Zero Voltage Vector Based Initial Magnet Polarity Identification Strategy of PMSM Drives

Accurate identification of magnet polarity seriously affects the accuracy of the initial position of a permanent magnet synchronous motor (PMSM) drive during flying start. In this paper, a novel magnet polarity identification method based on zero voltage vector (ZVV) pulse is proposed for flying start. According to the relationship between the current vector position and the initial position observed through high frequency signal injection method, an initial magnet polarity identification with high fault tolerance performance is proposed to improve the region misclassification problem which is caused by current sampling errors. The proposed method could accurately identify the magnet position at low speeds and improve the reliability of the initial position identification at flying start. The proposed method is validated on a 2.2-kW PMSM drive.