The rotor, bearing, stator, air gap, winding and commutator are all the basic components of the motor. The first four components are explained in detail below.
Rotor: In an electric motor, the moving part is the rotor, which rotates the shaft to transmit mechanical power. The rotor usually has conductors in which electric currents are carried, which interact with the magnetic field of the stator to generate the force of the rotating shaft. However, some rotors carry permanent magnets, and the stator retains conductors.
Bearing: The rotor is supported by bearings, allowing the rotor to rotate around the shaft. The bearing is supported by the motor housing. The motor shaft extends through the bearing to the outside of the motor to which the load is applied. Because the force of the load exceeds the outer bearing, the load is considered to be floating [54].
Stator: The stator is the fixed part of the electro-electric magnetic circuit, usually composed of windings or permanent magnets. The stator core consists of many thin metal sheets called laminations. Use lamination to reduce energy loss when using solid cores.
Air gap: The distance between the rotor and the stator is called the air gap. The air gap has an important role and is usually as small as possible, because a large gap has a strong negative impact on the performance of the motor. This is the main reason for the low power factor of the motor. The air gap increases the required magnetizing current. For this reason, the air gap should be small. In addition to noise and losses, very small gaps can cause mechanical problems.