Power Losses in Transformer , Minimization of Losses of transformer

     -: Power Losses in Transformer :- 
Transformer is a static machine and the various power losses occurring in a transformer are given below - 

1- Iron/ Core Losses

2- Copper / Ohmic  Losses 
3- Stray Load Loss 
4- Dielectric Loss 

Image Source : Google 

1- Iron or Core Loss :- Iron losses are caused by the alternating flux in the core of the transformer as this loss occurs in the core it is also known as core loss . 
                      Iron loss is further divided into two types - 
(i)- Hysteresis Loss
(ii)- Eddy Current Loss 

(i)- Hysteresis Loss - The core of the transformer  is subjected to an alternating magnetizing force , and for each cycle of emf ( Electromagnetic Force ) , a hysteresis  loop is traced out then power is dissipated in the form of heat ,then this is known as hysteresis loss . 
         

(ii)- Eddy Current Loss - If the magnetic circuit is made up of iron and if the flux in the circuit is variable , then currents will be induced by induction in the iron circuit itself then all currents are known as eddy current . 
                     The eddy current loss is given by equation - 
          PE = KEBMax²f²t²V   watts or J/sec

2- Copper / Ohmic Loss :- Copper loss occurs due to Ohmic resistance of the transformer windings . If I1 and I2 are the primary and the secondry current . R1 and R2 are the resistances of primary and secondry winging , then total copper loss- 

     Pc= I1²R1 + I2²R2 

These losses are varied according to load and known as variable losses . 

3- Stray Load Loss :- The presence of leakage fields in a transformer , induce eddy currents in the conductors , tank-walls , bolts etc due to these eddy currents stray load current rises . 

4- Dielectric Loss :- Dielectric loss occurs in the insulating materials particularly in oil and solid insulation . 
                                 The stray load loss and dielectric loss are very small and therefore these losses can be neglected . 


-: Minimization of Transformer Losses :-
1- Copper loss can be minimized by using thick copper wires.
2- The iron or core losses can be minimized by using silicon steel materials for the construction of the core of transformer.
3- Hysteresis loss - Hysteresis loss can be minimized by using a special alloy of iron core with silicon . This has the property of having narrow hysteresis loop .