What is the working principle of DC brushless motor?

The main body and driver of BLDCM is a typical mechatronics. The stator winding of the motor is mostly made of three-phase symmetrical star connection, which is very similar to the three-phase asynchronous motor. Its working principle is as follows.

The driver is composed of power electronic devices and integrated circuits. According to the position sensor, the controller triggers the power tubes in the driving circuit in order to change the current in order to drive the DC brushless motor. Receive the start, stop and brake signals of the motor to control the start, stop and brake of the motor, receive the position sensor signals and forward and reverse signals to control the on-off of each power tube of the inverter bridge, generate continuous torque, receive the speed command and speed feedback signals to control and adjust the speed, and provide protection and display.

The DC BLDCM has fast response, large starting torque, and the performance of providing rated torque from zero speed to rated speed. The speed of microprocessor is also faster and faster. It can realize the control of AC motor in a rotating two axis DC AC coordinate system, and properly control the current component of AC motor in two axes.

The mechanical power vehicle system is gradually replaced by the DC brushless motor. By properly controlling the current component of the two axes of the BLDCM, the performance of the BLDCM is similar to that of the DC motor.