Outcomes of overvoltage monitoring and fault location in underground distribution networks

This paper describes an information-measuring system for surge voltages monitoring and the outcomes of multi-year monitoring in 10 kV underground distribution networks. The statistical analysis of monitoring outcomes has shown a low level of the most often overvoltages in networks originating during restriking earth faults (REFs). For automatic location of REFs, a parametrical method based on the frequency properties of the network is offered.