An Three Phase Motor induction electric motor or 3 phase induction motor can be an AC electric motor in which the electric energy in the rotor needed to generate 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 fans,blowers, cranes,traction .It is a ac motor. The primary drawback of DC motors may be the existence of commutator and brushes, which require regular maintenance and we can not use DC engine in explosive and filthy environment. But induction motors are cheaper,tough,lighter,smaller,require less maintenance and may use in dirty and explosive environment. Slide s may be the imp aspect in this kind of motor.

There are 2 types of IM.

Squirrel cage IM

Slip ring IM

There are various 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 rate control technique of induction motor is important

Pole changing

Stator voltage control

V/f control

Slip power recovery

Rotor resistance control