Why is transformer oil necessary for transformer operation?

Transformer oil is necessary for transformer operation primarily for its insulating and cooling properties. It serves as an electrical insulator, preventing arcing and dielectric breakdown between live components. Additionally, transformer oil dissipates heat generated during operation, maintaining optimal temperature levels and ensuring efficient performance. The oil also helps to prevent oxidation and moisture ingress, which can degrade transformer components over time, thus enhancing the longevity and reliability of the transformer.