Oil-immersed transformer oil is an energy source that is inseparable from the operation of oil-immersed transformers. It is a powerful driving force to ensure the operation of oil-immersed transformers. For oil-immersed transformer oil, use relatively high-quality oil. Use inferior ones. However, with the continuous expansion of the oil-immersed transformer oil market, the quality of oil-immersed transformer oil is also uneven. Many unscrupulous vendors and manufacturers even add water to the oil-immersed transformer oil for sub-filling. In order to ensure whether water is added to the oil-immersed transformer oil, it can be measured by a test site method to verify whether water is added. This test is done in this way. The following is the detailed process:

Evaluating the humidity in insulating materials is an important factor in ensuring the reliability and service life of oil-immersed transformers. The humidity in the insulating oil is constantly changing, which may adversely affect the quality. In addition, most of the humidity is distributed in the insulating paper. Humidity affects the dielectric breakdown strength of solid and liquid insulating materials, and affects the aging rate of cellulosic insulating materials and the tendency to bubble formation during overload. Ambient temperature, load, aging, leakage and other factors will cause constant changes in humidity. Therefore, as the temperature of the oil-immersed transformer changes cyclically, continuous monitoring and diagnosis are required. This is more necessary for oil-immersed transformers with overload or peak load.

The total humidity in the insulation system of an oil-immersed transformer is determined by the moisture content of the cellulose and liquid. The humidity relationship between insulating paper and insulating oil depends only on temperature. When the temperature increases, the solubility of water in the insulating oil (the ability to hold water in the solution) increases, and moisture will be transferred from the insulating paper to the insulating oil.

Post time: Dec-28-2021