Breakdown process in rod-to-plane gaps with negative switching impulses

This paper reports with multiple techniques delineating complete sequence of events from the primary corona to the formation of the spark channel for large rod-to-plane air gaps with negative switching impulses. It is shown that starting with the primary corona the breakdown proceeds through the secondary corona and the intermittent appearance of the light flash to the final spark formation, qualitatively independent of the front time of applied impulses. The detailed analysis were made to each event, especially to the intermittent flash, with extremely high time-resolution techniques.