An induction electric motor or 3 stage induction motor is an AC electric engine in which the electric energy in the rotor had a need to generate torque is obtained by electromagnetic induction from the magnetic field of the stator winding

An induction electric motor which connects with a 3-phase supply called 3-phase induction motor. Example supporters,blowers, cranes,traction .It really is a ac engine. The primary drawback of DC motors is the presence of commutator and brushes, which require Three Phase Motor frequent maintenance and we can not use DC engine in explosive and filthy environment. But induction motors are cheaper,durable,lighter,smaller,require much less maintenance and can use in dirty and explosive environment. Slide s may be the imp element 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 acceleration control technique of induction engine is important

Pole changing

Stator voltage control

V/f control

Slip power recovery

Rotor resistance control