Why does transformer oil degradation occur, and how can it be prevented?

Transformer oil degradation occurs due to thermal stress, oxidation, moisture ingress, and contamination over time. High operating temperatures accelerate chemical reactions that break down oil molecules, forming acids and sludge. Exposure to oxygen and moisture further promotes degradation. To prevent this, maintain proper cooling to manage temperatures, use sealed or conservator systems to limit exposure to air and moisture, and implement regular oil testing and maintenance. Oil purification and regeneration processes can remove contaminants and restore oil quality, extending the transformer’s life.