An induction electric motor which connects with a 3-phase supply called 3-stage induction motor. Example enthusiasts,blowers, cranes,traction .It is a ac motor. The primary drawback of DC motors is the presence of commutator and brushes, which require regular maintenance and we can’t use DC engine in explosive and dirty environment. But induction motors are cheaper,rugged,lighter,smaller,require much less maintenance and may use in dirty and explosive environment. Slide s may be the imp factor 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
Auto transformer starter
Ac voltage three phase ac induction motor controller starter
Rotor resistance starter
Important braking methods are
Plugging or invert voltage braking
But one thing quickness control technique of induction engine is important
Stator voltage control
Slip power recovery
Rotor resistance control