Basic concepts of brushless motor

 According to the structure and working principle of the motor, we can divide the motor into the brushless motor, inner rotor brushless motor and outer rotor brushless motor.

Brush motor: also known as DC motor or carbon brush motor, it is the oldest motor type and the most numerous motor type by far. When the motor is working, the coil and commutator rotate, while the magnetic steel and carbon brush does not rotate. The alternating change of the direction of the coil current is completed by the commutator and brush rotating of the motor. This kind of motor has the advantages of relatively low cost, high torque, simple structure, and easy maintenance. However, due to structural limitations, so the shortcomings are also relatively obvious: 1, mechanical commutator sparks caused by the friction of the commutator and the brush, electromagnetic interference, noise, short life; 2, complex structure, poor reliability, many failures, the need for frequent maintenance; 3. Due to the existence of a commutator, the further decrease of rotor inertia is restricted, which affects the dynamic performance. So in the mold field is mainly used at slow speed and insensitive to the vibration of the car model, the ship model above rarely uses a brush motor.

Brushless motor: this is a brush motor industry, in addition to outside to use most of a motor, brushless dc motor without the use of mechanical brush device, using square wave self-control type permanent magnet synchronous motor, with hall sensor to replace carbon brush and commutator rotor in ndfeb permanent magnet materials, the performance has a great advantage compared with the general traditional dc motor. With high efficiency, low energy consumption, low noise, long life, high reliability, servo control, step-less frequency conversion speed regulation and other advantages, as for the disadvantage...... Is more expensive than the brush, not good maintenance, widely used in the model aircraft, high-speed car model, and ship model.

However, a single brushless motor is not a complete power system, brushless basically must be controlled by the brushless controller, that is, electric adjustment to achieve continuous operation. Ordinary carbon brush motors rotate windings, while brushless motors rotate magnets regardless of their external or internal rotor structures. So any motor is composed of a stator and a rotor.

The stator of the brushless motor is the part that generates the rotating magnetic field and can support the rotor to rotate. It is mainly composed of silicon steel sheet, enameled wire, bearing, and supporting parts. The rotor is a part that is rotated by the action of the stator rotating magnetic field, which is composed of a rotating shaft, a magnet, and a supporting part. In addition, the pole logarithm of the stator and rotor also affects the speed and torque of the motor.