Study on the insulation characteristics of environmentally friendly CF3I/N2/CO2 mixed gas

Abstract

AbstractSF6 gas is a kind of gas medium widely used in the insulation of power equipment. However, due to the greenhouse effect of SF6, new environmentally friendly gas that can instead of SF6 has been the goal for researchers. CF3I gas is one of the most promising alternative gases for SF6. In this paper, two-term Boltzmann equations of CF3I/N2/CO2 ternary gas mixture at 0.1 MPa and 300 K are calculated to obtain an electron energy distribution function (EEDF), an electron drift velocity Ve, a critical fold breakdown field strength (E/N)cr of the ternary mixed gas, and the synergy effect coefficient is used to analyze the synergy effect between the mixed gases. The calculation results show that the CF3I/N2/CO2 ternary mixture has a synergistic effect, and the 50% CF3I/40% N2/10% CO2 ratio scheme makes the mixed gas most likely to replace SF6 from the physicochemical properties. Comparing the calculated data of this paper with the data of other works of literature, the validity of the calculation method and calculation data in this paper is verified, which provides theoretical support for the research of SF6 alternative gas.