The use of SF6/N2 or SF6/CO2 mixture gas as a potential alternative to SF6 has attracted wide attention due to the easy availability of N2 and CO2, stable chemical and physical properties, non‐toxicity, nonflammability, and non‐combustion. In this paper, the simulation study of the arc formation process in the circuit breaker is carried out from a microscopic point of view. The simulation is based on the gas dynamics equation considering the complex collisions between charged particles and neutral molecules and obtaining the time‐varying law of the micro‐parameters such as the electron density and average electron energy in the arc forming process of SF6/N2 and SF6/CO2 mixture gas. The results can help us understand the characteristics of the mixture gas arc from the microscopic level, and provide a theoretical basis for the design and manufacture of the new circuit breaker.
Keywords SF6/N2 mixture gas, SF6/CO2 mixture gas, microscopic parameter, arc, circuit breaker