What is the process of transformer oil filtration as described in the wiki?

The process of transformer oil filtration involves the removal of impurities and moisture from transformer oil to enhance its dielectric strength and overall performance. This is typically achieved through techniques such as vacuum filtration, where the oil is subjected to reduced pressure to facilitate the extraction of water and particulate matter. The filtration process ensures that the transformer oil maintains its insulating properties, thereby prolonging the life and reliability of power transformers.