Study of Arcing Faults in 35 kV Isolated Neutral and Resonant Grounded Systems Using Mathematical Model of Arc Gap

The research indicates open-flame arc self-quenching conditions in 35 kV overhead distribution networks with low single phase-to-ground fault currents (less than 6 A): in an isolated neutral network and in a compensated network, taking into consideration arc extinction constraints for the channel modeling. The methodology stated (evidence from this 35 kV network studies) allows to analyze self-quenching conditions in case of overhead line faults. Transient single phase-to-ground faults such as direct lightning strikes, induced overvoltages due to a close lightning discharge, self-extinguishing faults entailed by incidents of mechanical origin can be considered. The analysis can be an integral part of the network reliability assessment, for instance, to calculate number of line cut-offs with fast or automatic reclosing.