Breakdown Characteristics of C $_{5}$ F $_{10}$ O/N $_{2}$ Mixtures in a Uniform Field Under AC Voltage

In this article, ac breakdown characteristics of C $_{5}$ F $_{10}$ O/N $_{2}$ mixtures under a uniform field with different concentrations of C $_{5}$ F $_{10}$ O, gap distances, and pressures are studied and compared to that of SF $_{6}$ . Additionally, the Paschen curves and insulation strength of the mixed gases are obtained. Results show that the insulation strength of 2% C $_{5}$ F $_{10}$ O/98% N $_{2}$ , 5% C $_{5}$ F $_{10}$ O/95% N $_{2}$ , 8% C $_{5}$ F $_{10}$ O/92% N $_{2}$ mixtures can reach approximately 70%, 75%, and 80%, respectively, of SF $_{6}$ under 0.5 MPa. Since the liquefaction temperature of C $_{5}$ F $_{10}$ O is 26.9 $^{\circ}$ C at 0.1 MPa, the available options for concentrations and pressure of C $_{5}$ F $_{10}$ O mixtures in practical applications are considered. 2% C $_{5}$ F $_{10}$ O/98% N $_{2}$ under 0.6 MPa with the minimum allowable temperature ( $-$ 20 $^{\circ}$ C) is approximately 81% of the insulation strength of SF $_{6}$ at 0.5 MPa. The Weibull distribution is applied to analyze experimental data to provide a reliable reference for the insulation application of C $_{5}$ F $_{10}$ O/N $_{2}$ mixtures. It is shown that the C $_{5}$ F $_{10}$ O/N $_{2}$ mixture is a reasonable alternative for SF $_{6}$ in electrical equipment.