What is the process of transformer oil filter plant and when is it required?

The process of a transformer oil filter plant involves the removal of impurities, moisture, and gases from transformer oil to restore its dielectric strength and extend the lifespan of the transformer. This typically includes stages such as pre-filtration, vacuum dehydration, and fine filtration. It is required when transformer oil shows signs of contamination, such as increased acidity or reduced insulation properties, often indicated by regular maintenance checks or after significant operational events.