Characteristics of N2/SF6 Mixture Gas on Creeping Discharge Developed in Narrow Gap with Backside Electrode

The flashover voltage with the backside electrode was lower than one without the backside electrode. Under μs pulse voltage application, we describe about characteristics of creeping discharge developed in narrow gap with the backside electrode. Using CCD camera and ultra-high speed camera, we observed the corona extension processes. As a result, the lowest flashover voltage was obtained in positive polarity of SF₆ content D=3%. In corona extension obtained using ultra-high speed camera, the peculiar differences were observed on the corona extension process. The corona extension increased, and rapid flashover were observed in D=3%. Using CCD camera, the small corona were detected from backside electrode.