An induction engine which connects with a 3-phase supply called 3-stage induction motor. Example fans,blowers, cranes,traction .It 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,rugged,lighter,smaller,require much less maintenance and may use in filthy and explosive environment. Slip 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 numerous starting and braking condition.
Important starting methods are
Star-delta starter
Auto transformer starter
Ac three phase ac induction motor china voltage controller starter
Rotor resistance starter
Important braking methods are
Regenerative braking
Plugging or reverse voltage braking
Dynamic braking
But one thing rate control technique of induction engine is important
Pole changing
Stator voltage control
V/f control
Slip power recovery
Rotor resistance control