INDUCTION MOTOR

 PREPARED BY EE IIT, Kharagpur

Contributors:  Dr.T.K. Bhattacharya,
                          Prof. N.K. De,

                          Prof. G.D. Ray

In this lesson of this module, the formation of rotating magnetic field in the air gap of an induction motor, is described, when the three-phase balanced winding of the stator is supplied with three-phase balanced voltage.

The balanced winding is of the same type, as given in lesson no. 18, for a three-phase ac generator.
Keywords: Induction motor, rotating magnetic field, three-phase balanced winding, and balanced voltage.
After going through this lesson, the students will be able to answer the following questions:
1. How a rotating magnetic field is formed in the air gap of a three-phase Induction motor, when the balanced winding of the stator is fed from a balanced supply?
2. Why does the magnitude of the magnetic field remain constant, and also what is the speed of rotation of the magnetic field, so formed? Also what is meant by the term ‘synchronous speed’?
Three-phase Induction

                                               

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