 WAZIPOINT Engineering Science & Technology: Simplified Diagram of Transformer

## Thursday, March 25, 2021

### Simplified Diagram of Transformer Transformer Simplified Diagram
To get an understanding of the simplified diagram of a transformer, you have to study the vector diagram of the transformer. The combined vector diagrams are shown herewith the figure VD-A, VD-B and VD-C.

The vector diagram of Fig. VD-A may be considerably simplified if the no-load current I0 is neglected. Since Iis 1 to 3 per cent of full-load primary current I1, it may be neglected without serious error. Fig. VD-B shows the diagram of Fig. VD-A with I0 omitted altogether.

In Fig. VD-B, V2, V1, φ2 are known, hence, E2 can be found by adding vectorially I2Rand  I2X2 to V2

Similarly, V1 is given by the vector addition of I1Rand  I1X1  to E1

All the voltages on the primary side can be transferred to the secondary side as shown in the figure, where the upper part of the diagram has been rotated through 180°. However, it should be noted that each voltage or voltage drop should be multiplied by the transformation ratio K.

The lower side of the diagram has been shown separately in Fig. VD-C laid horizontally where the vector for Vhas been taken along the X-axis.

It is a simple matter to find transformer regulation as shown in Fig. VD-C left or Fig. VD-C right.

It may be noted that V2= KV1 − I2 (R02 + jX02)
= KV1 − I2Z02.

Also, V1 = (V2 + I2 Z02) #3/K

Hope the simplified diagram of a transformer is explained simply, for more details you may read the transformer related to our other article.