Improving the dielectric strength of transformer oil is an important measure to ensure the safe operation of the transformer. The following methods can help you improve the insulation properties of transformer oil.
1. Remove water from the oil
Method: Use a vacuum oil filter or heating dehydration equipment to remove dissolved or free water in the oil.
Reason: Moisture is the main factor in reducing dielectric strength, which will form a conductive channel, resulting in breakdown.
Recommendation: Regularly monitor the moisture content of the oil to ensure that it is below the standard value (usually ≤35 ppm).
2. Filter impurities
Methods: The solid particles, fibers, and other impurities in the oil were removed by precision oil filter equipment.
Reason: Impurities will form a local electric field concentration, reducing the insulation performance of the oil.
Suggestion: During transformer maintenance or oil change, thoroughly clean the fuel tank and internal components to avoid secondary contamination.
3. Prevent oil aging
Methods: Antioxidant was added to slow down the aging rate of oil. Control operating temperature to avoid overheating.
Reason: Aging will lead to the production of acidic substances and sediments in the oil, reducing the dielectric strength.
Suggestion: Check the acid value and oxidation stability of the oil regularly, and replace the aging oil in time.
4. Regular testing and maintenance
Methods: Dielectric strength tests are performed regularly according to standards such as IEC 60156 or ASTM D877.
Reason: Find the problem in time and take targeted measures.
Suggestion: Establish oil quality monitoring files to record test results and oil quality trends.
5. Choose high-quality transformer oil
Method: Select a high-quality transformer oil that meets the standard, such as Class I or Class II oil.
Reason: High-quality oils have better insulation properties and oxidation resistance.
Suggestion: Ask for the inspection report of the oil at the time of purchase to ensure that its dielectric strength, moisture content, and other indicators meet the standard.
6. Control the operating environment
Method: Keep the transformer operating environment dry and clean to avoid the entry of external pollutants.
Reason: Environmental humidity and pollutants can affect the insulation performance of the oil.
Suggestion: Periodically check the tightness of the transformer to ensure that the fuel tank and respirator are working properly.