Three Phase Motor

An induction electric motor or 3 phase induction motor can be an AC electric engine in which the electric current in the rotor needed to produce torque is obtained by electromagnetic induction from the magnetic field of the stator winding

An induction motor which connects with a 3-phase supply called 3-phase induction motor. Example Three Phase Motor supporters,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’t use DC motor 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. Slip s is the imp element in this type 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

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 acceleration control technique of induction electric motor is important

Pole changing

Stator voltage control

V/f control

Slip power recovery

Rotor resistance control