Investigation on the Characteristics of CF3I Mixtures under Different Conditions

SF6 has strong greenhouse effect and many countries have enacted laws restricting the use of the gas. There have been several feasible alternatives to SF6. As an environmental friendly gas with excellent insulation characteristics, CF3I has the hope of replacing SF6 in medium and low voltage electrical equipment. In this paper, the influence of pressure and gap distance on the insulation strength of CF3I-N2 mixed gas was studied, and the results show that the insulation strength of CF3I-N2 mixture increases with the increase of CF3I mixture ratio. In slightly inhomogeneous electric field, the breakdown voltage of CF3I-N2 increases linearly with the increase of discharge gap, and the increase rate is proportional to the pressure. The breakdown voltage of CF3I-N2 gas mixture shows a trend of saturation with the gap in the extremely non-uniform electric field.