最佳PWM调制方式控制的无刷直流电机转子位置检测

为了实现最佳PWM调制方式无刷直流电机的无位置传感器控制，提出了一种新颖的转子位置信号检测方法，该方法通过检测线电压差的过零点，间接检测到断开相绕组反电动势的过零点，再将该过零点延迟30°电角度即可获得无刷直流电机绕组换相所必须的转子位置信号。实验证明，应用此检测方法构成的最佳PWM调制方式无刷直流电机无位置传感器控制系统可以运行在很宽的工作范围内。文中对该检测方法的原理进行了分析，得到了检测电路的结构图并通过实验验证了该方法的正确性和可行性。

The Detection of Rotor Position for Brushless DC Motors of Optimal PWM Modulation Control

In order to achieve the control for the sensorless brushless DC motor of the optimal PWM modulation, a novel method of dectection rotor position signals is prorposed. This method indirectly extracts the true back electromotive force （EMF） zero -crossing point of the floating phase by detecting the line voltage difference zero crossings. The commutation signal of the floating phase is obtained by lagging the back EMF zero -crossing point 30~. The method provides good motor performance over a wide operation range. Experimental results from a prototype brushless DC motor verify the analytical results and confirm the validity of the method.