With the rapid development of the power electronics industry, many high-performance semiconductor power devices have emerged and high-performance permanent magnet materials have been introduced, laying a solid foundation for the widespread application of permanent magnet brushless DC motors. Permanent magnet brushless DC motors have advantages that AC asynchronous motors, stepper motors and DC brushed motors do not have. Generally, they are suitable for occasions where DC brushed motors are used, and can basically be replaced by permanent magnet brushless DC motors.

Permanent magnet brushless DC motors have the following advantages:

• (1) They have excellent mechanical properties and adjustment characteristics, and can replace DC brushed motor speed regulation, variable frequency motor speed regulation, and asynchronous motor speed regulation with an acceleration and deceleration device.

• (2) They can operate at low speed and high power, eliminating the reducer and directly moving large loads.

• (3) They have all the advantages of traditional DC brushed motors, while eliminating the brush and collector ring structure.

• (4) They have excellent torque characteristics, good medium and low speed torque performance, large starting torque, and small starting current.

• (5) They have stepless speed regulation, a wide speed regulation range, and strong overload capacity.

• (6) Small size, light weight, high output.

• (7) Soft start and stop, good braking characteristics, can save the original mechanical brake or electromagnetic brake device.

• (8) The motor itself has no excitation loss and brush loss, high efficiency, and good comprehensive power saving effect.

• (9) High reliability, good stability, strong adaptability, simple repair and maintenance.

• (10) Resistant to bumps and vibrations, low noise, small vibration, smooth operation, and long life.

• (11) No sparks, especially suitable for public places, anti-interference, and good safety performance.

Application scenarios of permanent magnet brushless DC motors

Permanent magnet brushless DC motors are widely used in national defense, military, aerospace, office machinery, computers, audio, ventilation equipment, household air conditioning, automatic control, instrumentation, automobiles and other fields. In computers, optical drives, hard disks, etc., a large number of very precise permanent magnet brushless DC motors of various forms are used.

At present, most of the motors of electric bicycles, electric motorcycles, and micro electric vehicles use permanent magnet brushless DC motors. The annual output of permanent magnet brushless DC motors for electric bicycles reaches tens of millions of units nationwide, and there are also electric bicycle motor manufacturers with an annual output of millions of units. Permanent magnet brushless DC motors are now gradually used in sightseeing vehicles, tour buses, forklifts, and electric vehicles. Permanent magnet brushless DC motors for electric vehicles are the most widely used and highest-output type of permanent magnet brushless DC motors.