An induction electric motor or 3 stage induction motor is an AC electric electric motor in which the electric energy in the rotor needed to generate torque is obtained by electromagnetic induction from the magnetic field of the stator winding
An induction electric motor which connects with a 3-stage supply called 3-phase induction motor. Example supporters,blowers, cranes,traction .It is a ac engine. The main 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,tough,lighter,smaller,require much less maintenance and will use in filthy 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 numerous starting and braking condition.
Important starting methods are
Star-delta Three Phase Motor 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