What is transformer oil used for?

Transformer Oil – Functions and Applications

Transformer oil is an important liquid insulating medium in power systems, primarily serving three core functions: insulation, heat dissipation, and arc extinguishing.

Main Functions

Insulation Protection: The insulation strength of transformer oil is significantly higher than that of air. It isolates charged parts at different potentials, prevents short-circuit breakdown, and protects against moisture erosion.

Heat Dissipation and Cooling: Losses from the copper windings and iron core during transformer operation generate heat. The oil transfers this heat to the radiator through convection, ensuring normal equipment operation.

Arc Extinguishing: When the contacts of an oil circuit breaker or voltage regulator switch are operated, the oil decomposes and generates a large amount of hydrogen gas. This gas quickly absorbs heat and, using its high thermal conductivity, effectively extinguishes the arc.

Additional Benefits: Transformer oil also inhibits oxidation, helping to extend the service life of the equipment.