Moreover, the rotor of BLDC is a permanent magnet, so it doesn't need the carbon brush to be electrified for commutation, and it only needs to be electrified in different directions. It can be said that BLDC motor is the most ideal speed regulating motor at present.
Related introduction:
The general brushless DC motor is essentially a servo motor, which consists of a synchronous motor and a driver, and the driver is a variable frequency motor. Variable-voltage variable-speed brushless DC motor is a real brushless DC motor, which consists of a stator and a rotor. The stator consists of an iron core, and the coil adopts a "forward-reverse-forward-reverse …" winding.
This produces a fixed north-south magnetic field group. The rotor consists of a cylindrical magnet (with a shaft in the middle) or an electromagnet plus a slip ring. Brushless DC motor can generate torque and can't control the direction, but it inherits the inherent advantages of DC motor-constant power and constant torque speed regulation.
So in any case, the motor is a meaningful invention. When used as a DC generator, the invention can generate DC current with continuous amplitude, thus avoiding the use of filter capacitors, and the rotor can be permanent magnet, brush excitation or brushless excitation. When used as a large motor, the motor will produce self-inductance, so it is necessary to adopt protective devices.
The cost of DC variable voltage speed regulation is extremely low, and it will not produce harmonics, so the speed regulation effect of this kind of motor can be comparable to that of automobile automatic gearbox. Brushless DC motor also has the function of automatic stop and braking, so it can be used in some special fields. The history of DC motor has a long history, and the earliest motor invention (US patent 132) is DC motor.
There are many kinds of motors and generators in the world today, with different functions, which are dizzying, and motor patents are also emerging one after another. Li Jiajun's rotating magnetic field DC motor can bring a revolution in the field of transmission, and Xia Zhui's fixed magnetic field brushless DC motor is also an extraordinary invention. I believe there will be more and better motor inventions in the future.