Question

Explain the energy losses in a transformer. How are they minimized?

Answer 1

The energy losses in a transformer are as follows:

(i) Hysteresis loss : This is due to the repeated magnetisation and demagnetisation of the iron core caused by the alternating input current. This can be minimised by using alloys like mumetal or silicon steel.
(ii) Copper loss : Current flowing through the primary and secondary windings lead to Joule heating effect. Hence some energy is lost in the form of heat. Thick wires with considerably low resistance are used to minimise this loss.
(iii) Eddy current loss : Varying magnetic flux produces eddy current in the core. This leads to wastage of energy in the form of heat. This can be minimised by using a laminated core made of stelloy; an alloy of steel.
(iv) Flux loss : Flux produced in the primary coil is not completely linked with the secondary coil due to leakage. This can be minimised by using a shell type core.
Also, due to the vibration of the core, sound is produced, which causes a loss in the energy.