Evaluation of arc quenching characteristics of various gases using power semiconductors

This paper presents the arc quenching abilities of various gases studied using a power semiconductor switching technique. The technique uses an insulated gate bi-polar transistor (IGBT) to inject current and apply voltage to the plasma arc. Using this technique, arcs in free recovery condition after a 50 A steady state condition were investigated in SF6, CO2, O2, N2, air and Ar gas flows. Furthermore, at a specific time high voltages of about 1.1 kV and 1.7 kV μ were applied to the residual decaying arcs by the IGBT to elucidate the arc re-ignition process and recovery properties. These systematic experiments further enabled us to estimate the interruption probability versus the voltage application time. From these results, the voltage application time for 50% successful interruption was estimated for various gases, with the results showing a direct relation to the interruption capabilities of the respective gases. These results were then compared to the electron density measurement results and numerical simulation results to confirm their validity. All data obtained from the experiments and simulation is expected to be useful for elucidating the arc quenching physics and also for the practical application of arc quenching phenomena.