无位置传感器无刷直流电机位置检测与启动控制研究

摘要

To solve the problem of precise control for the sensorless Brushless DC Motor (BLDCM), the BEMF-crossing-zero detecting is in used to detect the rotor position, and a three-stage starting strategy is presented to start the motor in this paper.The terminal voltage signal of three-phase winding are converted into digital signal, and the relationship between the terminal voltage in the winding and the BEMF of the phase is derived.Then, the zero-crossing point of BEMF could be resolved.When the motor is beginning to start, a specified phase is break-over to find the initial position of the rotor.Then, the external-synchronous acceleration is switched to the self-synchronous acceleration.The simulation model of sensorless BLDCM is built based on LabVIEW.The results of simulation and the experiments verified the effectiveness and reliability of the strategy.%针对无位置传感器无刷直流电机控制问题,提出利用反电动势过零检测法实现电机转子位置检测,并利用三段式启动法完成电机启动.将无刷电机三相绕组的端电压信号转换成数字信号,并推导出三相绕组端电压与未导通相反电动势的关系,通过计算解出反电动势的过零点.电机启动时先通过对指定相通电,确定转子的初始位置,进而由外同步加速状态切换到自同步状态.文章采用Labview软件搭建了电机启动控制系统仿真模型,最后通过仿真和试验验证了所提方案的有效性与可靠性.