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Transformer losses
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Copper, iron and flux leakage losses.
Copper loss (I²R), eddy-current and hysteresis loss in the core, and flux leakage. Large power transformers reach 99% efficiency.
Laminated cores and oil cooling.
Losses become heat.
In more detail
Real transformers lose energy through resistance in the windings, eddy currents in the core and hysteresis losses. Laminated cores and good design keep efficiency above 95 percent for large units.
Real-world uses
- Engineers design transformers to minimise losses in distribution networks.
- Efficiency ratings guide purchase of distribution transformers.
- Engineers designing transformers choose good cores and windings to reduce losses and keep them efficient.
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Frequently asked questions
What is the largest loss?
It depends on the design, but copper and core losses dominate in most transformers.
Why is efficiency so high?
Large transformers have little resistance and well-designed cores.
What are the main losses in a transformer?
Copper losses from the resistance of the windings, iron losses from hysteresis and eddy currents, and flux leakage.
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