In order to make the motor rotate, the control unit must determine the sequence of turning on (or off) the power transistors in the inverter according to the position of the motor rotor sensed by the hall sensor, and then make the current flow through the motor coil in sequence to generate a forward (or reverse) rotating magnetic field, and interact with the magnet of the rotor, In this way, the motor can rotate clockwise / counterclockwise. When the motor rotor rotates to the position where the hall sensor senses another group of signals, the control unit turns on the next group of power transistors, so that the circulating motor can continue to rotate in the same direction until the control unit decides to stop the motor rotor, and then turns off the power transistors (or only turns on the lower arm power transistors); If the motor rotor is reversed, the power transistor will turn on in reverse order.