Power Transformer and Distribution Transformer

Transformer plays an important role in the area of electrical engineering. Transformer is used either for raising or lowering the voltage of ac supply. It is used at electrical energy generating station where basically it raise the voltage level of an ac supply and it is also used at substations where it is used to lowering the voltage at suitable level. In power engineering it occupies a very important place.In this article, we will study about power transformer and distribution transformer. The power transformer are located at power generating stations whereas the distribution transformers are installed in the localities of the city.


The power transformers are installed at the sending and receiving end of the high voltage transmission lines whereas the distribution transformers are installed at the near to the load centre to provide utilization at the consumers premises. Distribution transformers are basically pole mounted.


Power transformers are usually operated at full load or nearly full load in simple words we can say that the power transformer gives high efficiency at full load or nearly full load. On the other hand distribution transformers are operates at light load during major part of the day.


The rating of a power transformer is very high in the orders of MVA and power transformer generally rated above 100MVA. The rating of distribution transformer is smaller and distribution transformer are generally less than 100MVA.


The insulation required in case power transformer is more in comparison to the distribution transformer because the power transformer generally operates at very high voltage in order of 400KVA, 220KVA, 132KVA etc.


The power transformer is basically larger in size as comparatively distribution transformer.

Copper Losses and Iron Losses

The power transformers are operated at nearly full load so iron losses are less so the power transformer are designed to have low copper losses. However, the load on the distribution transformer vary time to time so these transformer designed to have low iron losses.