Gas Pressure Impact on Thermal Interruption Capability of Puffer Type SF6 Circuit Breakers

摘要

In this paper, influence of fill pressure of a SF6 circuit breaker on its thermal interruption capability is studied. For this purpose, one simplified physical model is combined with a black box model to make it possible to predict the circuit breaker performance depending on its various physical parameters. To couple these two models, the thermal conduction power loss of the arc column near current zero used in black box models is expressed as a function of gas pressure. To validate the developed combined model, some short circuit current interruption experiments have been performed at different rates of transient recovery voltages and different rates of current. The experimental results are in good accordance with the theoretical estimations.