Construction of three phase synchronous Motor

Here, The Construction of three phase synchronous motor is described very effectively in this article, this theory is one of the most important and useful for practical knowledge. All the description is explained below.

Construction of three phase synchronous Motor

A three-phase synchronous motor consists of the following essential parts:

1.Laminated stator core with three-phase armature winding.

2.Revolving field complete with a mortises winding and slip rings.

3.Brushes and brush holders.

4.Two end shields to house the bearings that support the shaft.

The stator core and windings of a synchronous motor are similar to those of a 3-phase

squirrel-cage induction motor or a wound-rotor induction motor.

The leads for the stator winding, marked T1,T2 and T3, terminate in a terminal box usually mounted on the side of the motor frame.

The rotor is generally a salient pole rotor. The number of rotor field poles must equal the

number of stator field poles.

In order to eliminate hunting and to develop the necessary starting torque when A.C. voltage is applied to the stator, the rotor poles contain pole-face conductors which are short-circuited at their ends as shown in below image

This a mortises or damper winding consists of solid copper bars embedded at the surface

of the pole face and short-circuited at each end by means of a shorting strip as shown in below image.

The field circuit leads are brought out to two slip rings mounted on the rotor shaft.

Carbon brushes mounted in brush holders make contact with the two slip rings.

The terminals of the field circuit are brought out from the brush holders to a second terminal

box mounted on the motor frame.

What parts are the main for synchronous machine?

There are two main parts of the synchronous motor stator and rotor. The stator is the stationary part and rotor is the rotating part. The three-phase AC supply is given to the stator of the motor.