Characteristics of the DC arc forcing interruption and reignition conditions

In this paper, the character of the di/dt, dv/dt at current zero was investigated at 270V DC forcing interruption. The experiment was performed on a synthetic test circuit, with the VI electrode of AgWC, plane type, diameters of 23mm, and gap 2mm. The Equivalent circuit was studied, and the simplify equation was expressed. The di/dt was influenced by the parameters in forcing circuit, while the dv/dt not only influenced by the frequency modulation circuits but also the parameters in forcing circuit. With high speed camera, arc mode was researched. The interruption characteristics of different test current with different forcing frequency were research. Under the experiment of 1500A current forcing interruption, it showed that with the forcing frequency increases (2.3 kHz, 3.1 kHz, and 4.2 kHz), the di/dt increase too, and the dv/dt seems decreased a little. And under the same frequency, with the test current increase, the di/dt, dv/dt both decreased. And the reignition at 2100A is different, the arc voltage polarity reversal and rise to normal value smoothly.