C₄F₇O-CO₂混合气体自由燃弧电弧特性实验研究

C₄F₇N-CO₂ mixture is a likely to replace SF₆ as insulation and arc extinguishment medium. Therefore, study on the arcing characteristics of C₄F₇N-CO₂ mixture is meaningful. We experimentally studied the arcing characteristics of CO₂, 40%C₄F₇N-60%CO₂ mixture and SF₆ with the free arc-buring experiments between the rod-rod electrodes. Various parameters including arc voltage, current, current-zero characteristics as well as spectrum distribution are measured. The arc energy accumulation and dissipation processes are analyzed through the Mayr arc model. Then the arc temperature distribution along the radial direction is obtained by combining the Abel inverse transformation and the Boltzmann method. The results show that the CO₂ arc is very volatile. The arc voltage of CO₂ arc is lower than that of SF₆ and fluctuates repeatedly during the arcing period. Adding C₄F₇N into CO₂ improves the stability of the arc and decreases the arc voltage. The addition of C₄F₇N decreases the arc energy accumulation during the arcing period as well as the arc energy dissipation coefficient before current-zero. The arc core temperatures of CO₂, 40%C₄F₇N-60%CO₂ mixture and SF₆ at the current peak are 20 000 K, 18 900 K and 14 900 K, respectively, and the arc diameters are 13 mm, 17 mm, and 23 mm. C₄F₇N is effective in reducing the temperature at the arc core.