Experimental design of a series arc load side detection algorithm for DC microgrid protection

Unplugging of energized loads in dc microgrids can cause safety concerns to users in residential areas. Sustained series arcs are more relevant in dc systems than in ac due to absence of current zero crossing. In this paper, the series arcs are detected from the load side, wherein, the proposed algorithm monitors the drop in load capacitor voltage associated with the intial electrode dependent series arc voltage. The original contribution of this work includes the experimental analysis of response of the arc detection algorithm with different discrete bandpass filter configurations and time constants. Experiments are conducted by generating series arcs for a stable 100V supply and noisy 600V supply with 300 Hz noise. The design requirements like robustness to low frequency grid voltage fluctuations, high frequency switching noise, detection time, and the threshold detection voltage are achieved and the most favourable design choices are highlighted.