An induction electric motor which connects with a 3-stage supply called 3-phase induction motor. Example followers,blowers, cranes,traction .It is a ac electric motor. The primary drawback of DC motors may be the presence of commutator and brushes, which require regular maintenance and we can not use DC electric motor in explosive and dirty environment. But induction motors are cheaper,durable,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 numerous starting and braking condition.
Important starting methods are
Auto transformer starter
Ac voltage three phase ac induction motor china controller starter
Rotor resistance starter
Important braking methods are
Plugging or invert voltage braking
But one thing rate control technique of induction engine is important
Stator voltage control
Slip power recovery
Rotor resistance control