Influence of Micro-water on Decomposition Characteristics of C4F7N/CO2 Mixed Gas

Preliminary research shows that $C_{4}F_{7}N$ has good insulation properties and environmental protection characteristics, and has great potential as a substitute for SF
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in gas-insulated equipment. According to the allowable value of the micro-water content in the equipment, the micro-water content is set to 0 and $1000\mu L/L$, and the sphere electrodes are used to simulate the quasi-uniform electric field. The influence of micro-water on the decomposition characteristics of $C_{4}F_{7}N/CO_{2}$ mixed gas was studied through experiments. The experimental results show that there is no significant difference between the decomposition products under the two conditions, and they are mainly $C_{2}F_{6}, C_{3}F_{8}, C_{3}F_{6}, CF_{4}, CF_{3}CN$, CO, $C_{2}N_{2}, COF_{2},C_{2}F_{5}CN$. The production of $C_{2}F_{5}CN$ has increased while the production of $C_{3}F_{6}$ and $C_{2}N_{2}$ has been inhibited after adding micro-water. The relevant research can provide the basis and reference for the engineering application of $C_{4}F_{7}N/CO_{2}$ mixed gas. If $C_{4}F_{7}N/CO_{2}$ mixed gas is used as a gas medium for insulating equipment, try to ensure that the inside of the equipment does not contain moisture or less moisture.