Study on characteristics and detection of DC arc fault in power electronics system

In power electronics System, dc arc, which is difficult to extinguish and to be detected, would easily lead to fire causing great harm to the lines and equipment around[1]. In this paper, a dc arc generation simulation unit is designed. A series DC arc can be generated by dragging the moving electrode away from the fixed one with the help of the stepper motor. During experiments, gap distances, the shape and speed of electrodes are changed to determine the influence factors of the characteristics of series dc arcs. Based on the experimental data, the V-I characteristic of the dc arc is determined. In addition, by analyzing the pulse characteristics of arc current and source output in corresponding window of time, a dc arc fault detection methodology is proposed based on the abrupt change of current and source output, thus makes a good foundation for future works.