Why is oil filtration necessary in a traction transformer, and how is it carried out?

Oil filtration removes impurities like moisture, particles, and dissolved gases that can degrade insulating properties and lead to electrical faults. Filtration is carried out using specialized equipment that circulates the oil through filters and degassers. The process may involve heating the oil to improve filtration efficiency. Regular oil filtration maintains the dielectric strength and thermal conductivity of the oil, ensuring the transformer’s reliable operation and extending its service life.