Feasibility of Fluoronitrile (C4F7N) as a Substitute to Sulphur Hexafluoride (SF6) in Gas Insulated Application: A Review

Reducing Green House Gas (GHG) emissions has been an area of immense concern due to the abnormal climate changes from global warming. SF 6 has a stable structure and superior dielectric qualities, which make it a commonly utilized media in the insulation industry. Due to its greenhouse gas effect, restrictions have been implemented on SF 6 production and usage worldwide, and considerable efforts have been undertaken to find suitable alternative gases to replace SF6. In this research work, the feasibility analysis of C4F7N as a substitute to SF 6 is performed. Synthetic and non-synthetic gases used for insulation are discussed. Insulation characteristics of C4F7N are summarized in detail in terms of effective ionization coefficient, breakdown voltages, stability, and voltage-time characteristics. Due to the relatively high boiling point, the gas should be mixed with buffering gases. The mixture optimization procedure was also presented. Finally, the feasibility and scope of C4F7N for current applications are analyzed, and further research direction is pointed out.