Transformer vacuum filling is a process used during the manufacturing or maintenance of oil-filled transformers. Its main purpose is to fill the transformer with insulating oil under vacuum conditions. This method ensures that the oil penetrates all internal parts of the transformer without trapping air or moisture.
1. Remove Air and Moisture
- Air bubbles and moisture inside the transformer can lead to partial discharges, corona effects, and insulation failure.
- Vacuum removes these contaminants from the windings and insulation before oil is introduced.
2. Ensure Complete Oil Penetration
- Under vacuum, the oil can fully saturate the insulation materials (e.g., paper, pressboard), which is essential for proper dielectric performance.
3. Improve Dielectric Strength
- Air and moisture reduce the dielectric strength of the insulation system.
- Vacuum filling ensures the transformer oil maintains its maximum insulating capability.
4. Prevent Formation of Voids
- Filling under vacuum avoids the formation of air pockets or voids in the insulation, which could cause localized heating and electrical breakdown.
5. Enhance Transformer Reliability and Longevity
- Proper vacuum filling significantly reduces the risk of insulation failures and extends the service life of the transformer.
