Wind turbine transformer oil system maintenance involves regular oil testing, filtration, and degassing to ensure the oil maintains its insulating and cooling properties. Oil samples are tested for parameters such as moisture content, acidity, dielectric strength, and gas levels. If necessary, filtration is performed to remove solid contaminants, and degassing units are used to eliminate gases and moisture. Oil regeneration may also be performed if the oil shows signs of degradation. Proper maintenance extends the transformer’s operational life and prevents costly failures.