Journal of Physics D Applied Physics · 1993 · 38 citations · 4 references
Materials ScienceMaterials EngineeringChemical EngineeringElectrical EngineeringEngineeringMicrostructureGlow DischargeSurface ScienceMechanical EngineeringElectrode Surface RoughnessSf6 GasTime-dependent Dielectric BreakdownMaterial PerformanceGas Discharge PlasmaPure Sf6ElectrochemistryElectrical Insulation
The effect of electrode surface roughness on the breakdown potential in SF6, SF6-N2, and SF6-CO2 has been measured and calculated using two surface-roughness models (a multi-ridge model and a single-needle-tip-protrusion model). The calculations are in reasonable agreement with the experimental results, indicating that although the addition of N2 or CO2 to SF6 reduces the sensitivity of its dielectric strength to electrode surface imperfections, the breakdown strength of SF6 gas remains higher than that of SF6-N2 and SF6-CO2 (50%-50%) even when pR for the multi-ridge model is as great as 40 kPa mm representing an exceptional surface imperfection in engineering application conditions. Only in the case of a single needle-tip protrusion can the dielectric strength of the SF6-CO2 be slightly higher than that of SF6 gas, and in no case will the dielectric strength of SF6-N2 exceed that of pure SF6 as has been reported by some previous investigators.
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