An AC induction motor transforms electrical energy into mechanical energy. It is the most common in the industry. The engine device is quite simple, work occurs at a constant current.
Engine device. It consists of three parts: housing, stator and rotor.
The housing serves as a protection for the rotor and stator from various damages and environmental influences. Rigidly fixed parts are mounted in it.
The stator is a fixed part of the engine. The main parts are: magnetic circuit and bed. In the engine bed, a pressed magnetic core forms a stator (electromagnetic core). Due to the core, a magnetic field is formed, which is rotational. An air gap separates the rotor and stator.
The rotor is the moving part of an electric machine.
Due to the rotation of the magnetic field and located inside the conductor, an interaction occurs on which the principle of operation of an asynchronous motor is based. The stator creates a rotating magnetic field and is fixed motionless. The starter itself is a core made of steel, on which there is a winding, fixed in special grooves.
A magnetic field, when crossing the rotor winding, forms an EMF inside. As a result of this action, a current flows in the winding, which interacts with the
magnetic flux. When the magnetic field of the stator interacts with the current in the rotor, a torque is generated. The rotation of the rotor occurs in the same direction as the field, but with a small lag.
As a result of the entry of electrical energy from the network into the stator winding, it becomes mechanical.
The number of plus pairs determines the engine speed.
An induction motor device divides them into two types: with a phase and squirrel-cage rotor. They differ in the arrangement of the rotor. The squirrel-cage starting winding is rods that are made of aluminum or copper, and are closed by two rings on both sides of the rotor. In the phase winding of the motor is connected by a "star".
The engine device can be of various protection:
Protected - equipped with a device that protects against accidental contact with parts that are energized or moving. Prevents foreign objects from getting inside. Cooling takes place at the expense of the environment.
Splash-proof, protects against water droplets that fall perpendicularly or at an angle of forty-five degrees. Such a device does not prevent the penetration of dirt and dust.
Closed, in which the internal parts are protected from external influences (drops, dust).
Dustproof, protects against the penetration of even fine dust.
Closed blown, which is blown outside by a ventilation system. The fan is located outside and is covered by a casing.
Sealed, it is a very powerful protection against penetration from the outside.
The induction motor is controlled by sensors that regulate the rotor speed. The simple arrangement of the engine made it possible to use it not only in production, but also in everyday life.