Why is filtration and regeneration of transformers oil required during maintenance?

Filtration and regeneration are required to restore the insulating and cooling properties of transformer oil. Over time, oil accumulates moisture, acids, sludge, and solid particles that reduce dielectric strength and heat transfer efficiency. Filtration removes water and particulates, while regeneration processes use adsorbents to remove acids and oxidation byproducts. This extends oil life, improves transformer reliability, delays costly oil replacement, and helps maintain insulation integrity during long-term service.