How does oil filtration of transformer extend service life?

Filtration extends transformer life by removing moisture, particles, and oxidation byproducts that trigger dielectric failure and thermal stress. Lower moisture raises breakdown voltage and reduces partial discharge risk. Cleaner oil improves cooling by preventing sludge deposits that restrict flow and heat transfer surfaces. Degassing removes air that can accelerate oxidation and lower dielectric strength. By restoring oil properties, filtration protects paper insulation, reduces fault probability, and helps maintain stable operation under design loading and temperature rise limits.