An Three Phase Motor induction motor or 3 phase induction motor can be an AC electric motor in which the electric energy in the rotor had a need to produce torque is obtained by electromagnetic induction from the magnetic field of the stator winding
An induction electric motor which connects with a 3-phase supply called 3-phase induction motor. Example fans,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 motor in explosive and dirty environment. But induction motors are cheaper,rugged,lighter,smaller,require much less maintenance and may use in filthy and explosive environment. Slide s is 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 voltage controller starter
Rotor resistance starter
Important braking methods are
Regenerative braking
Plugging or invert voltage braking
Dynamic braking
But one thing speed control technique of induction motor is important
Pole changing
Stator voltage control
V/f control
Slip power recovery
Rotor resistance control