Rotor is an important part of brushless motor. It can be divided into inner rotor and outer rotor according to classification. Their functions are different for the motor. Attention should be paid to distinguish them before use.

1、 Different references

1. Inner rotor: rotating body supported by inner bearing, rigid connection or additional shaft.

2. Outer rotor: rotating body supported by outer bearing, rigid connection or additional shaft.

2、 Different principles

1. Inner rotor: the rotor in brushless motor, which is composed of the rotor core and the closed conductor embedded in the core, generates high-speed rotary motion driven by the rotating magnetic field generated by the stator winding. Both ends of the rotor adopt rolling bearings and are installed and fixed in the end cover of the motor housing.

2. Outer rotor: maintains a magnetic balance at the center of the motor. However, in the case of unstable force, any slight displacement will make the rotor deviate from its original position, and may even completely lose contact with the stator. The suspension control of radial position is used to eliminate the rotor eccentric displacement of brushless motor.

3、 Different uses

1. Inner rotor: the main components of high-speed rotation in power machinery or working machinery such as motor, generator, gas turbine and turbine compressor.

2. Outer rotor: space-saving, compact and beautiful design. Suitable for installation in the impeller, with good cooling effect. No V-belts, additional tensioning belts or other equipment are required.