The brushless DC motor is composed of a motor body and a driver, and is a typical mechatronic product. Since the brushless DC motor runs in a self-controlled manner, it will not add a start winding to the rotor like a synchronous motor that is started under heavy load under variable frequency speed regulation, nor will it cause oscillation and loss of step when the load changes suddenly. Brushless DC motor is a device that changes in frequency, so it is also called DC frequency conversion. The international common term is BLDC. The operating efficiency, low-speed torque, and speed accuracy of the brushless DC motor are better than those of the inverter of any control technology. Brushless DC motors use semiconductor switching devices to realize electronic commutation, that is, electronic switching devices are used to replace traditional contact commutators and brushes. It has the advantages of high reliability, no reversing sparks, low mechanical noise, no brushes, low interference, smooth operation, long life, low maintenance costs, etc. It is widely used in high-end audio jacks, video recorders, electronic instruments and automated office equipment .