Question

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

Answer 1

$1)$ Hysteresis Loss: The repeated magnetisation and demagnetisation of the iron core caused by the alternating input current, produces loss in energy called hysteresis loss. This loss can be minimised by using a core with a material having the least hysteresis loss. Alloys like Mu-metal and silicon steel are used to reduce hysteresis loss.
$2)$ Copper loss: The 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.
$3)$ Eddy current loss(Iron loss): The varying magnetic flux produces eddy current in the core. This leads to the wastage of energy in the form of heat. This loss is minimised by using a laminated core made of stelloy, an alloy of steel.
$4)$ Flux Loss: The flux produced in the primary coil is not completely linked with the secondary coil due to leakage. This results in the loss of energy. This loss can be minimised by using a shell type core. In addition to the above losses, due to the vibration of the core, sound is produced, which causes a loss in the energy.