Insulation Strength and Decomposition Characteristics of a C 6 F 12 O and N 2 Gas Mixture

This paper explores the decomposition characteristics of a new type of environmentally friendly insulating gas C 6 F 12 O and N 2 mixed gas under AC voltage. The breakdown behavior of 3% C 6 F 12 O and N 2 mixed gas in quasi-uniform field was investigated through a breakdown experiment. The self-recovery of the mixed gas was analyzed by 100 breakdown experiments. The decomposition products of C 6 F 12 O and N 2 under breakdown voltage were determined by gas chromatography–mass spectrometer (GC-MS). Finally, the decomposition process of the products was calculated by density functional theory, and the ionization energy, affinity, and molecular orbital gap of the decomposition products were also calculated. The properties of the decomposition products were analyzed from the aspects of insulation and environmental protection. The experimental results show that the 3% C 6 F 12 O and N 2 mixed gas did not show a downward trend over 100 breakdown tests under a 0.10 MPa breakdown voltage. The decomposition products after breakdown were CF 4 , C 2 F 6 , C 3 F 6 , C 3 F 8 , C 4 F 10 , and C 5 F 12 . The ionization energies of several decomposition products are more than 10 eV. The Global Warming Potential (GWP) values of the main products are lower than SF 6 . C 2 F 6 , C 3 F 8 , and C 4 F 10 have better insulation properties.