Study on the Compatibility between Eco-friendly Insulating Gas Mixture and Solid Materials of Used in Gas-insulated Transformers Based on Thermal Acceleration Method

Inhalt:
(CF3)2CFCN-CO2 gas mixture is an eco-friendly alternative to SF6. Investigating its compatibility with solid materials used in gas transformers and promoting the application of (CF3)2CFCN-CO2 gas mixtures are of great significance for power grid companies and power systems to achieve carbon emission reduction and carbon neutrality. At present, there are few reports on the compatibility. This paper proposed the test method of the compatibility between gas mixtures and solid materials, set up the compatibility test platform and investigated the thermal stability of the 9%(CF3)2CFCN-91%CO2 gas mixture. The thermal accelerated aging test of the 9%(CF3)2CFCN-91%CO2 gas mixture and 12 kinds of solid materials at different temperatures was carried out. The results of the thermal stability test show that the initial decomposition temperature of the gas mixture in the 316L stainless steel sealed tube is 300 °C. The initial decomposition temperature of the gas mixture in the quartz sealed tube is 400 °C. The material of the sealed tube has a great influence on the initial decomposition temperature of the gas mixture. The results of the material compatibility test show that the 9%(CF3)2CFCN-91%CO2 gas mixture couldn’t react with 12 kinds of solid materials in the range of 40 °C to 110 °C. That is to say, the compatibility between the gas mixture and 12 kinds of solid materials is good in the range of 40 °C to 110 °C.