There are several ways to test transformer oil to assess its condition and performance. Here are some of the most common techniques used:
- Dielectric Strength Test (BDV Test): This test measures the dielectric strength of transformer oil by applying an increasing voltage until a breakdown occurs. The test is used to assess the ability of the oil to withstand electrical stress without breaking down.
- Dissolved Gas Analysis (DGA): This test measures the concentration of various gases that are generated by the oil and insulating materials inside the transformer when subjected to thermal and electrical stress. The presence and quantity of certain gases can indicate the type and severity of the fault that is occurring in the transformer.
- Water Content Test: This test measures the amount of moisture present in the transformer oil. The presence of moisture can affect the dielectric strength of the oil and lead to other problems such as corrosion.
- Acid Value Test: This test measures the acidity of the transformer oil. High levels of acidity can indicate the presence of oxidized compounds and other degradation products that can cause damage to the transformer.
- Interfacial Tension Test: This test measures the surface tension between the transformer oil and water. A low interfacial tension can indicate the presence of contaminants or degradation products in the oil.
- Color Test: This test provides a quick visual assessment of the condition of the transformer oil. Darker or discolored oil can indicate the presence of contaminants or degradation products.
- Furans Analysis: This test measures the concentration of furanic compounds in the transformer oil. These compounds are formed when cellulose insulation is subjected to high temperatures, and their presence can indicate the degree of degradation of the transformer insulation.
By using these different techniques, it is possible to obtain a comprehensive assessment of the condition of transformer oil and to identify any potential problems that may need to be addressed.