Transformers are into the most efficient electrical equipment commercially manufactured and main is targeted and maintained efficiency of the transformer
All the most transformers of sizes start from 1 KVA to 1000 KVA will have a full-load efficiency of from 95% to 98.5%.
The transformers, which will lower the efficiency of a transformer, in case are losses, which appear in the iron core and which appear in the windings of the transformer.
The iron losses of the transformer are explained in the above given question.
The occur losses in the windings are because the resistance of the copper wire. When current flows through a copper wire, losses appear in the form of heat in the transformer , the same as condition of when an ordinary electric hot plate is turned on .
The wire used in quality transformers is generally made of copper as well as Aluminum is sometimes used in low quality transformers in the rare case .
Where life expectancy is not important to long of the transformer and transformers which only have a constant load.
These metals are into the best commercial metals for conducting electricity. They offer the least amount of resistance. Therefore, energy will be lost in the form of heat through the windings in few amount
These losses run on the order of 1% to 2% of the full-load rating of the transformer . They will be inversely as the square of the load.So more discuss about efficiency of transformer.
Efficiency of a Transformer Formula
Power loss occurs in transformer so the transformer does not give out the whole power consume to it.
- Output Power = KVA Cosф
- Iron Loss = Wi
- Copper Loss = Wc
Condition For Maximum Efficiency Of Transformer
- Copper loss increase with the increase in the load but the iron loss remains constant. Efficiency increases with the increase in load. At some load, the efficiency becomes maximum and then it decreases with further increase in load. Let us obtain the condition for the maximum efficiency of the transformer.
η = output/input
= input – output/input
- Thus given equation , we can find the load current for which the efficiency will become the maximum.
- Multiplying the given equation by V2 and divided by 1000
Where, Wc is Full-Load Copper loss & KVA is Full Load kVA
All Day Efficiency of Transformer
Let’s discuss about all day efficiency of transformer. Generally or commercial efficiency of transformer is given by the ratio of output power to the input power then we can calculate all day efficiency of transformer.
But For distribution of transformer the figure of efficiency does not give real or true idea about its performance. Because of distribution transformer peak load comes only for small period of time during the day and for most of the period is unused loaded.
But it should be connected continuously to the transformer to the supply.So the iron losses occur for the whole day when copper losses will be depending upon the condition of load and it will be very small .
So that is the main reason of the distribution transformer is designed for small iron losses.
Now See , performance of the distribution transformer can be better known on the basics of energy rather than the given power .
For this term all day efficiency is designed.
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