energy , transformers and efficiency

Energy losses in a transformer
1. Some energy is lost from a transformer as heat which mean that power output is less than power input
2. Efficiency of the transformer is less than 100%


Heating effect in the coil
3. When current flows in the coil, some power is dissipated as heat. This loss reduced by using thicker wire made of a good conducter like cooper.


Eddy current in the iron core
4. Changing magnetic field causes the electron in the soft iron core to circulate around  as eddy currents. It produces heating in the core and causes further loss of power.
5. Eddy current are reduced by using luminated core made up of a number of thin iron sheets glued together with thin iron sheets glued together with thin layer insulation between them.


Magnetisation and demagnetisation of the core
6. Core is continually magnetised  and demagnetisation by the changing magnetic field produced by the alternating current in the primary coil.
7. This energy loss is reduced by using soft iron for the core


Leakage of magnetic flux
8. Magnetic flux produced by the primary current is not completely linked to the secondary coil.
9. Some of the input energy is not transferred to the output of the transformer.
10. This loss can reduced by winding the secondary and primary coils on top each other.