The optimum structural design of low-voltage arc chamber based on simulation and analysis of flow field

Abstract

In the process of arc splitting in low voltage switching devices, the flow field in arc chamber plays an important role. In order to accelerate the arc quenching, one of the most common methods is to enhance the gas flow through adding gas material in arc chamber currently. Meanwhile, in the recent research, it has been found that improving the flow field through optimum structural design of arc chamber is another effective way, especially in the recent market trend that the low voltage switching devices are getting more and more small size. In this paper, with the CFD software of Fluent, the model of arc chamber which is from a type of auto transfer switch equipment and the magneto-hydrodynamic model of the arc were established. The distribution of the flow field in arc chamber during arc igniting was calculated. On the basis of analyzing the flow field, an optimum arc chamber was proposed. In the meantime, experimental investigations on the former and the optimum arc chambers were carried out under the same conditions. The arc current and arc voltage were measured. The arc motion process and back commutation phenomenon captured with the high-speed camera were observed. The results show that the interruption performance of the optimum arc chamber is improved prominently.