对转式永磁无刷直流电机无位置检测控制策略研究

Research on Sensorless Control of Contra-Rotating Permanent Magnet BLDC Motor

研究对转式永磁无刷直流电机基于反电势过零点的无位置传感器控制策略,通过理论推导和实验验证该策略能够运用于对转式永磁无刷直流电机。针对静止状态下启动困难问题,基于d轴正向增磁、反向去磁导致铁芯饱和程度不同而产生电感差异及q轴到d轴之间电感差异的原理,提出了一种通过施加6个短时电压脉冲即可判断磁极转子初始位置的检测方法,以及施加2个短时导通相电压脉冲获得换相时刻的启动加速方法,并进行实验验证。结果表明:基于电感差异原理提出的磁极转子初始位置检测和启动方法能够有效解决启动困难问题,扩大了对转式永磁无刷直流电机的运用范围,提高对转式永磁无刷直流电机无位置检测控制性能。

The position sensorless control based on back EMFs of contra-rotating Permanent Magnet BLDC motor was discussed and verified by the theoretical derivation and experiments. A method with six pulseswas proposed to detect the pole rotor position at standstill,another method for start-up with two pulses was presented based on the difference of inductance. Finally,the experiments verified that the initial position estimation method and start-up method could implement the contra-rotating PMBLDC motor switching to position sensorless control mode based on back-EMFs.