无位置传感器无刷直流电机位置检测与启动控制研究
Research on the Position Detection and Start Control for Sensorless Brushless DC Motor

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。
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