The calculation of arc conductance in SF6-N2 mixture gas circuit breaker

The arc conductance is a significant factor to predict and determine the thermal interruption in a high-voltage gas circuit breaker. For the gas circuit breaker the calculation of the arc conductance is not easy, because of arc plasma, which has several thousand degrees, super- and sub-sonic flows, high electric field condition, non-ideal gas properties, thermal radiation heat transfer, the nozzle ablation, and so on. This paper presents the calculation technique of the arc conductance by using arc plasma simulation. The analyzed results of the arc conductance in a SF₆-N₂ mixture gas in comparison with pure SF₆ gas are also presented.