Arc generator for photovoltaic arc fault detector testing

Arcing in photovoltaic (PV) power systems is a significant concern due to the potential for property damage from a PV system fire and personal safety from electrical shock hazard or electrocution if an arc is undetected and left unmitigated. Arc fault detectors are now required by the National Electric Code and Underwriters Laboratories (UL) standard 1699B is currently under development to address testing and listing requirements for these devices. One significant challenge that arose in UL1699B draft standard development process was the way in which an arc was created to test the arc fault detector, i.e. how is an arc generated that faithfully replicates real-world conditions yet can be done with high repeatability in the laboratory? While UL standards, test protocols, and test beds exist for AC-system arc fault detectors, arcs in DC systems, particularly PV, are different. This paper reports on the results of a project to develop a DC arc generator (AG) suitable for use in the development and testing of DC arc fault detectors.