新的对转无刷直流电机转子位置检测方法

New Method of Rotor Position Detection for Counter-rotating Magnet Brushless DC Motor

主要对对转永磁无刷直流电机的无位置传感器检测方法进行了研究。在分析反电动势过零点法的基础上,研究了电机中性点电位和母线中性点、虚拟中性点电位之间的关系。通过对反电动势、线电压差值和反电动势差值的定性分析,提出了简化的线电压差值过零点和反电动势差值过零点检测方法。该方法通过在线检测线电压和相电流,经过软件计算得到换相点,无需构造虚拟中性点,简化了硬件电路。仿真实验结果表明该方法正确有效。

The method based on back-EMF to estimate the two rotors position is derived through analyzed the relations between a neutral point voltage of windings and a neutral point voltage of bus, a virtual neutral point voltage of windings. Importantly, two simplified methods are proposed based on the analysis of back-EMF, line voltage difference and back-EMF difference. It can indirectly gain zerocrossing of back EMF signal from line voltage and phase current calculation without the need to sense or reconstruct the motor mid-point and simplifying the hardware circuits. The simulation results show that the methods can obtain rotor position preferably.