Time-resolved radiation measurement and energy balance of air arcs

To improve the interruption performance of electric switching apparatus, it is important to understand the dissipative process of injected energy between the electrodes. In this paper, the time-resolved energy balance of air arcs is investigated under various currents and gap distances. The total energy injected to the arc is divided into two parts: energy transferred to electrodes which mostly causes the melting and vaporization of electrodes; energy dissipated from the arc column to surroundings by radiation, convection and conduction. Relevant data including arc voltage, arc current, radiation power of the arc and the ablated mass of electrodes are recorded in time. Under some assumptions and approximation, the time-resolved power balance can be obtained.