Copper Power Loss in a Transformer
The total power loss in a transformer that takes place in the winding resistance of a transformer is known as the copper loss. This power loss in a transformer should be kept as low as possible to increases the efficiency of the transformer.
To reduce the copper loss, it is essential to reduce the resistance of primary and secondary windings of the transformer. This power loss in a transformer is also known as the variable loss as it is dependent on the square of load current.
To determine the copper loss, short circuit test on transformer is performed.
Iron Loss (Pi) in a Transformer
The power loss in a transformer that takes place in its iron core is known as the iron loss. In the transformer, flux set up in the core remains constant from no load to full load. Hence this power loss in a transformer is independent of load and also known as constant losses of a transformer.
This power loss in a transformer has two components named hysteresis loss and eddy current loss. To determine the iron loss, open circuit test of transformer is performed.
Hysteresis Loss in a Transformer
The hysteresis loss of a magnetic material depends upon its area of the hysteresis loop. Hence the magnetic materials such as silicon steel, which has very small hysteresis loop area, are used for the construction of the core to minimize this power loss in a transformer.
The hysteresis loss (Ph = KhVfBm1.6) is frequency dependent. As we increase the frequency of operation, this power loss in a transformer increases proportionally.
Eddy Current Loss
Due to alternating flux in the transformer, some EMF is induced in the transformer core. This induced EMF causes some currents to flow through the core of the transformer. These currents are known as eddy currents. The core of transformer has some finite resistance. Hence due to the flow of eddy currents, some power loss in a transformer takes place and it is known as eddy current loss
(Pe = KeVft2Bm2).
The eddy current loss is minimized by using the laminated core. These laminations are insulated each other by mean of a thin varnish coating. Hence each lamination acts as a separate core of a small cross sectional area, offers a high resistance to the flow of eddy currents.
Therefore, with the use of laminations in the core, eddy currents and eddy current losses are reduced. This power loss in a transformer is also frequency dependent. It is directly proportional to the square of operating frequency.
- Single Phase Transformer Working Principle
- Ideal Transformer on No Load
- Construction of Three Phase Transformer
- Types of Transformers
- Equivalent Resistance and Reactance of Transformer
- Equivalent Circuit of Single Phase Transformer
- Power Loss in a Transformer
- Open Circuit Test of Single Phase Transformer
- Short Circuit Test on Single Phase Transformer
- Transformer Efficiency
- Regulation of Transformer
- Instrument Transformers
- Polarity of Transformer Windings
- Significance of Vector Group of Transformer
- Buchholz Relay Construction | Working
- Why current transformer secondary should not be opened