关键词: 无位置传感器, BLDCM, 反电动势, 过零点

Abstract: In view of the high cost of sensorless brushless DC motor (BLDCM) and its environment-sensitive operation reliability, combined with the actual project needs, the working principle of BLDCM is analyzed and design scheme of position sensorless BLDCM control system based on STM32F031 is proposed. In this scheme, the rotor initial position of the motor is detected by rotating voltage pulse injection in order to avoid the reversal phenomenon when the motor starts at rest, and the zero crossing point of back electromotive force is used to predict the commutation point of the motor during the motor operation. Experimental results show that the system runs stably and reliably, starts smoothly, and has high accuracy of commutation position, which has high application value.

Key words: positionsensorless, BLDCM, backelectromotiveforce, zero-crosspoint