An induction engine which connects with a 3-phase supply called 3-stage induction motor. Example enthusiasts,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 engine in explosive and dirty environment. But induction motors are cheaper,durable,lighter,smaller,require much less maintenance and will 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.

three phase ac induction motor china 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 electric motor is important

Pole changing
Stator voltage control
V/f control
Slip power recovery
Rotor resistance control