Write different energy losses in transformer and their remedy
Answers
Although transformers are very efficient devices, small energy losses do occur in them due to four main causes:
Resistance of windings – the low resistance copper wire used for the windings still has resistance and thereby contribute to heat loss
Flux leakage – the flux produced by the primary coil may not be all linked to the secondary coil if the design of the core is bad.
Eddy currents – the changing magnetic field not only induces currents in the secondary coil but also currents in the iron core itself. These currents flow in little circles in the iron core and are called eddy currents. The eddy currents cause heat loss. The heat loss, however, can be reduced by having the core laminated.(thin sheets of soft iron insulated from one another). (See image below)
Hysteresis – The msgnetization of the core is repeatedly reversed by the alternating magnetic field. The repeating core magnetization process expends energy and this energy appears as heat. The heat generated can be kept to a minimum by using a magnetic material which has a low hysteresis loss. Hence, soft iron is often chosen for the core material because the magnetic domains within it changes rapidly with low energy loss.