Study of Factors Affecting Electric Arc Current in Vacuum Unstable Cathode Composites

Abstract

As the arc occurs over a period, it affects the lifespan and safety of the cathode contact surface, reducing the safety of the arc extinguishing chamber of the circuit breaker. This research aims to study the factors that affect arcing in a vacuum. Therefore, the selection of materials and equipment for making the cathode and insulation is crucial in influencing arcing in a vacuum. The purpose of this research is to develop the contact surface of the circuit breaker from composite cathode materials to compare greater efficiency. From studying the parameters that affect the arc factor, the stability of cathode material parameters, and the proportion of ion flow by numerical analysis, it was found that the critical current of the constant current depends on the thermal conductivity of the cathode material, which is a very important result for the development of cathode materials. These results are like the data obtained from other research, which indicates that the analysis by the cathode spot model, used to determine the thermal conductivity in a low-current vacuum arc, may be applied to materials that easily vaporize. Moreover, reducing thermal conductivity could enhance arc stability by minimizing electron backflow from the plasma region.