Fast Commutation Error Compensation for BLDC Motors Based on Virtual Neutral Voltage

Precise commutation signal is the prerequisite for the efficient operation of brushless direct current (BLDC) motors. However, the low-pass filter, nonideal current, circuit, and software retarding can bring about the commutation errors that will deteriorate the performance of BLDC motors, for example, resulting in larger current ripple and noise. To eliminate the commutation errors quickly and improve the performance of the motor, a novel compensation method is proposed in this letter. The compensation time is calculated by a counter. And the start-stop signals of the counter are obtained by the virtual neutral voltage. The proposed method requires none voltage or current sensor and has a faster compensation speed and higher precision than the traditional compensation method based on the integration of virtual neutral voltage. The effectiveness of the proposed method is verified by comparable exp eriments using an 80-W BLDC motor.