Mumbai University > FE > Sem 1 > Basic Electrical and Electronics Engineering

Marks: 4 M

Year: May 2014

There are 2 losses in transformer:

Copper Loss: -

In a transform, winding are not ideal and every winding has same resistance. The loss that takes place due to winding resistance is called loss.

R1= Resistance of primary winding.

R2= Resistance of secondary winding.

Primary Copper Loss=I2 R1 watt

Secondary Copper Loss= I2 R2 watt

So Total Copper Loss= (I2 R1 + I2 R2) watt

Iran Loss or Core Loss (W1):-

Due to applied alternating voltage, an alternating blur is produce in the core when any magnetic material is placed in alternating magnetic field, the hysteresis loss and eddy current loss takes place in the magnetic material. Thus the hysteresis loss and eddy current loss take place inside the core of a transformer. These 2 losses together are called “Core Loss”

RATING OF TRANSFORMER IN KVA AND IN KW:-

The rated transformer output is limited by heating and hence losses in the transformer i.e. Copper Loss and Iron Losses depend upon the voltage and current, and are almost unaffected by the power factor of the load.

∴ The transformer rated output is expressed in KVA and not in KW.