Diagnostics of Post-Arc Electron Number Density in a Model Circuit Breaker

During the circuit breaker breaking process, the behavior of the current zero arc is one of the key factors to determine the success of the gas circuit breaker breaking. Passive optical diagnostics can provide crucial microscopic information about the current zero arc. In this paper, different media current zero arc interference fringes are obtained by laser interferometry diagnostic technology, and the evolution of post-arc electron density is obtained through phase difference inversion. Compared with the decay rates of electron surface density in different arc extinguishing media, the results show that Air < CO2 < SF6, which is consistent with the excellent arc extinguishing performance of SF6 in practical engineering applications. By exploring the comprehensive control mechanism of gas arc post-arc decay process under different factors, this study provides a theoretical basis for the development of new circuit breakers.