Effect of O₂ on partial discharge and decomposition characteristics of C₅F₁₀O/CO₂/O₂ gas mixture

This paper investigates the effect of O2 on the partial discharge (PD) and decomposition characteristics of C5F10O/CO2/O2 gas mixture employed as an eco-friendly gas insulating medium. We found that the insulation performance of the C5F10O/CO2/O2 gas mixture is less degraded as the content of O2 is less than 4%. However, PDIV+ is significantly reduced, and the discharge repetition rate increases drastically when the O2 content exceeds 4%. The PD decomposition products of C5F10O/CO2/O2 mainly include CF4, C2F6, C3F8, C3F6, CF2O, C2F6O3, and C3F7H. The addition of 2% O2 has a strong inhibitory effect on the generation of CF4, C2F6, C3F6, C3F8, CF2O, and C2F6O3. This work provides guidance for the application of the C5F10O/CO2/O2 gas mixture.