An induction engine or 3 phase induction motor is an AC electric electric motor in which the electric energy in the rotor needed 
to create 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-stage induction motor. Example supporters,blowers, cranes,traction .It Three Phase Motor really is a ac electric motor. The primary drawback of DC motors may be the existence of commutator and brushes, which require frequent maintenance and we can not use DC engine 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 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 quickness control technique of induction electric motor is important
Pole changing
Stator voltage control
V/f control
Slip power recovery
Rotor resistance control
