Construction of Three Phase Synchronous Motor

Similar to d.c. machine where there is no constructional difference between a generator and motor, There is no difference between the construction of synchronous motor and the alternator, both being the synchronous machines.

The synchronous motor construction is basically similar to rotating field type alternator. It consists of twp parts :

i) Stator : Consisting of a three phase star or delta connected winding. This is excited by a three phase a.c. supply.

ii) Rotor : Rotor is a field winding, the construction of which can be salient (projected pole) or non salient (cylindrical) type. Practically most of the synchronous motors use salient i.e. projected pole type construction. The field winding is excited by a separate d.c. supply through slip rings.

Construction of Three Phase Synchronous Motor

Fig. 1 Schematic representation of three phase synchronous motor

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