AC Breakdown Characteristics of C₅F₁₀O/CO₂ Gas Under Different Electrode Surface Roughness.

In this work, we explored the ac breakdown characteristics of C5F10O/CO2 mixtures under different electrode surface roughness. It was found that sulphur hexafluoride (SF6) outperforms C5F10O/CO2 mixtures in the ac breakdown experiments. The breakdown voltages of C5F10O/CO2 and SF6 are negatively correlated with the surface roughness, while SF6 is more sensitive to the electrode surface roughness than C5F10O/CO2. To reach the dielectric strength of SF6, an increase in pressure or mixing ratio of C5F10O/CO2 is needed, while the liquefaction temperature of C5F10O/CO2 will increase simultaneously. Considering the limitation of 20% drop in dielectric strength, the maximum acceptable surface roughness of the gases is determined. The controlling requirement of electrode surface roughness ${R}_{t}$ of 30 $\mu \text{m}$ in SF6 equipment is suitable for the design of C5F10O/CO2 equipment. [ABSTRACT FROM AUTHOR]