永磁同步电机转子磁极的极性判别方法

摘要

The magnetic saturation effect can be used to distinguish the rotor magnetic polarity of a permanent magnet synchronous motor (PMSM). Started with the high-frequency model of PMSM, a rotor magnetic polarity detection method was presented from carrier-frequency component signals, derived from PWM inverter as the information source. In order to provide rotary carrier-frequency component signals, three-phase triangular carrier SPWM modulation was adopted in the inverter, and then the cartier-frequency component voltage (CFCV) expression was given under this modulating pattern. The carrier-frequency component current (CFCC) equation of the PMSM was deduced in α-β frame, and the amplitude of the saturation term contained the magnet polarity information. The heterodyne process circuit extracted the saturation term to distinguish of the rotor magnetic polarity. The simulation and experimental results verified the correctness of the theoretical analysis. Motor parameters or additional special high frequency signal injection are not necessary in this method. It provides a way for the rotor magnetic polarity detection.%针对永磁同步电机转子磁极的极性判别问题,依据电枢绕组的磁饱和特性,从电机的高频数学模型入手,提出一种以PWM逆变器载波频率成份作为高频信号源的极性判别方法.为了能够产生旋转的载波频率成份信号,逆变器采用三相三角波载波SPWM调制方式,并给出了该调制模式下的载波频率成份电压表达式.推导了α-β坐标系下的载波频率成份电流矢量方程,方程中的饱和分量幅值包含转子磁极的极性信息.利用外差处理电路提取饱和分量,进而实现了对永磁同步电机转子磁极的极性辨别.仿真和实验结果证明了理论分析的正确性.该方法不需要知道电机的精确参数,也不需要向电机注入额外的特定高频信号,能够判别PMSM转子磁极的极性.