Research Work on Arc Flash in LVDC Systems

Research work based on systematic measurements and testing in high-power labs has been done in the last years with respect–among others-to DC arc stability and risk parameters, to similarities and discrepancies between AC and DC arcs as well as to testing of PPE. In the paper, the correlations and dependencies of the DC arc risk parameters (arc power, arc energy, thermal incident energy) from the electric system parameters are analyzed. Conclusions are drawn on how to calculate arc power and arc energy. On this base an algorithm was developed for determining these parameters and to select the appropriate PPE against the thermal hazards of the DC fault arc. The algorithm was already introduced in the new edition of the user guide DGUV-I 203-07S.