DC arc plasma dynamics and electrical signatures investigated by 3D reconstruction and signal analysis

Abstract In the context of the increasing deployment of direct current (DC) power systems, particularly in the aeronautical sector, DC arc fault detection remains a major challenge. Gaining a deeper understanding of the electrical signature of arcs and identifying their characteristic features are therefore essential for the development of new detection devices. To address this challenge, this paper presents an experimental study on the dynamics of DC electric arc columns generated by contact separation. These plasmas are investigated in three dimensions using a stereoscopic setup, and their electrical characteristics are also analyzed. The experimental results reveal a strong correlation between the electrical fluctuations and the arc column deformation, identified through frequency analysis of the measured signals. A detailed investigation of the mechanisms governing the column deformation and its stability is carried out, highlighting several coupled phenomena such as kink instabilities. Finally, the column deformation is quantified, and its evolution is studied as a function of various parameters, including current, inter-electrode gap, pressure, surface roughness and electrode materials.