An Three Phase Motor induction engine or 3 phase induction motor can be an AC electric electric motor in which the electric current in the rotor had a need to generate torque is obtained by electromagnetic induction from the magnetic field of the stator winding

An induction motor which connects with a 3-phase supply called 3-stage induction motor. Example supporters,blowers, cranes,traction .It really is a ac engine. The main drawback of DC motors is the presence of commutator and brushes, which require regular maintenance and we can not use DC electric motor in explosive and filthy environment. But induction motors are cheaper,tough,lighter,smaller,require less maintenance and will use in filthy and explosive environment. Slide s is the imp factor in this kind 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 reverse voltage braking

Dynamic braking

But one thing velocity control technique of induction motor is important

Pole changing

Stator voltage control

V/f control

Slip power recovery

Rotor resistance control