An induction motor or 3 phase induction motor is an AC electric engine in which the electric energy in the rotor needed to produce torque is obtained by electromagnetic induction from the magnetic field of the stator winding

An induction motor which connects with a 3-stage supply called 3-phase induction motor. Example supporters,blowers, cranes,traction .It is a ac electric motor. The main drawback of DC motors is the existence of commutator and brushes, which require frequent maintenance and we can not use DC electric motor in explosive and filthy environment. But induction motors are cheaper,tough,lighter,smaller,require much less maintenance and may use in dirty and explosive environment. Slide s is the imp aspect in this type of motor.

There are 2 types of IM.

Squirrel cage IM

Slip ring IM

There are many starting and braking condition.

Important starting methods are

Star-delta starter

Auto transformer starter

Ac voltage controller starter

Rotor resistance starter

Important braking methods are

Regenerative braking

Plugging or invert voltage braking

Dynamic braking

But one thing Three Phase Motor quickness control technique of induction electric motor is important

Pole changing

Stator voltage control

V/f control

Slip power recovery

Rotor resistance control