三相无刷直流电动机控制系统的设计

he installation of rotor position sensor brings many problems to brushless DC motor, therefore, sensorless brushless DC motor has great advantage in some case. In this paper, The principles of brushless DC motor and its control system are analyzed in detail, as well as the principle of back-EMF which is used to get the rotor position. Based on this, a design used ML4428 and IR2130 as a core for controlling the BLDCM without any rotor position sensor is given, including the calculation methods of several important parameters and the detailed hardware circuit. The start process of the BLDCM system and the speed regulation process are also explained amply in the paper.The system is very cheap and responds quickly.