What is the working principle of brushless DC motor?

Dc brushless motor is composed of main body and driver, which 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. Here's how it works.

The driver is composed of power electronic devices and integrated circuits, etc. According to the position sensor of the motor rotor position in order to trigger each power tube in the drive circuit, the controller carries out orderly commutating to drive the brushless DC motor. Accept the start, stop and brake signals of the motor to control the start, stop and brake of the motor, accept the position sensor signals and positive and negative signals to control the on-off of each power tube of the inverter bridge to generate continuous torque, accept speed instructions and speed feedback signals to control and adjust the speed, provide protection and display.

Dc brushless motor response fast, large starting torque, from zero speed to rated speed can provide rated torque performance, microprocessor speed is getting faster and faster, can realize the AC motor control in a rotating two-axis vertical coordinate system, appropriate control of the AC motor in the two-axis current component.

Mechanically-powered vehicle systems are gradually being replaced by brushless DC motors. Proper control of the DC brushless motor in the two-axis current component can achieve similar DC motor control and have the same performance as the DC brushless motor.