Multi-physics Modeling for Thermal Interruption Capability Estimation of CO2/O2 Mixed Gas Circuit Breaker

This paper presents a multi-physics model for the estimation of thermal interruption capability in a CO2/O-2 mixed gas circuit breaker (GCB). The ohmic loss of the insulation gas is calculated from the current continuity equation and utilized as a heat source for thermal fluid analysis. To accurately estimate the thermal interruption capability of a GCB adopting a CO2/O-2 mixture, we proposed a multi-physics model coupled with an electric model and a thermal fluid dynamics model. The validity of the proposed multi-physics model was verified by comparing it with experimental data. Subsequently, interruption indices were predicted using the calculated parameters to estimate the thermal interruption capability.