there are several losses in a transformer that prevent it from attaining 100% efficiency. One is core loss, which can be divided into Hysteresis losses, Eddy currents and Magnetostriction loses. see for more details http://en.wikipedia.org/wiki/Transformer#Energy_losses
Single phase Transformer 200 KVA ,Efficiency = 98% Full load 0.8 pf. lagging , Maximum efficiency of the transformer is on load 150 kVA Which copper losses (I22R2e) = Core losses (PFe) . Find Core losses ?
increase the coating of transformer.
To calculate the no load current from transformer & core loss is also calculated.
Iron losses (Pi) are independent of of load which occur due to pulsation of flux in the core. Iron losses include both Hysteresis loss and eddy current loss and is same at all the loads.
Iron loss it includes the core loss is partically the same at all loads and copper loss the value of cu loss is found from short circuit test
since at no load only excitation current(responsible for core loss ie iron loss) flow on the primary side so core loss current will be 1A and core loss = v1*i1*powerfactor. core loss = 1*11000*0.24= 2640watt.
eddy current can be reduced by using laminated cores. and also be reducing the thickness of the stampings. transformer iron loss is the combination of eddy current loss and hysterisis loss. both the losses depend on core of the transformer and iron loss is a constant loss.
To calculate the no load current from transformer & core loss is also calculated.
Iron losses (Pi) are independent of of load which occur due to pulsation of flux in the core. Iron losses include both Hysteresis loss and eddy current loss and is same at all the loads.
Iron loss it includes the core loss is partically the same at all loads and copper loss the value of cu loss is found from short circuit test
Core loss is one of the many fixed losses in a transformer. This means that no matter the loading of the transformer there this loss would be fixed unlike copper loss which depends on the loading of the transformer.
since at no load only excitation current(responsible for core loss ie iron loss) flow on the primary side so core loss current will be 1A and core loss = v1*i1*powerfactor. core loss = 1*11000*0.24= 2640watt.
Iron losses are termed as core losses. There are mainly two losses - Copper loss and iron loss. Iron loss is no load loss.
eddy current can be reduced by using laminated cores. and also be reducing the thickness of the stampings. transformer iron loss is the combination of eddy current loss and hysterisis loss. both the losses depend on core of the transformer and iron loss is a constant loss.
Yes, that is almost true, apart from a very small copper loss in the primary winding that carries the small magnetising current. The core loss (iron loss) depends on the applied voltage. This loss is measured by the open-circuit test, carried out at the working voltage.
Basically two types: 1. Copper losses:- when the transformer is loaded, current flows in primary and secondary winding, there is loss of electrical energy due to the resistance of the primary winding, and secondary winding and they are called variable losses. These losses depend upon the loading conditions of the transformers. Therefore, these losses are also called as variable losses. 2. Iron losses or core losses:-The losses that occur in the core are known as core losses or iron losses. Two types of iron losses are: > eddy current loss > Hysteresis loss.
The maximum efficiency condition in distribution transformer is said to be occurred when iron loss = copper loss
It doesn't, really. The power loss in transformers is broken down into copper loss and iron loss. The copper loss comes from the resistance of the windings in the transformer and depends on the load current, while the iron loss in the magnetic core depends on the magnetic flux density and is constant if the supply voltage is constant.
The short-circuit test runs the rated current through the windings of the transformer to measure the copper-loss, or power lost in the winding resistances. Because the transformer is run at low voltage for this test, there is very little additional power loss in the iron core of the transformer.