The influence of magnetic and electric fields to the arc motion in low-voltage apparatus

摘要

An arc chamber is designed, where the gradient of electric flux density along the arc moving direction can be generated. The capacitor bank circuit is used to provide the test power supply, and the input current is adjustable. High speed CCD camera is adopted to record the images of arc moving, arc current and arc voltage are measured respectively. The experimental result shows that the electric field can influent the distribution of arc current greatly. To explain the result, a numerical model is established to simulate arcing process. The simulation shows how the gradient of electric strength affects the current distribution and arc moving. The numerical result also shows, for a certain arc chamber configuration, with increasing of current the arc driving affect of magnetic will be weaken, the reason partly lies on the affect of electric field.