Pilot Tests of FasTR Method for Locating Transient Faults in Medium Voltage Underground Power Networks

This paper presents the results of pilot tests performed on a real medium voltage (MV) underground network in Switzerland with the aim of assessing the performance of a fault location system. The deployed fault location platform is based on a very sensitive and precise acquisition system which is capable of capturing perturbations or events on a dedicated portion of a given MV network. Thanks to a post processing algorithm based on the tenets of time reversal theory, FasTR method, an accurate localization of relevant events can be worked. Due to the fact that each acquisition system shares a clock reference based on a GPS antenna, the localization accuracy is within tens of meters. To the best of the Authors knowledge, this is the first time that the FasTR-based fault location technique is validated through live tests. The pilot network is a three branch system part of live radial MV distribution feeder consisting of a total of 2.6 km long underground three-phase cables. The branched lines are composed of coaxial cables of different types. The tests involve solid- and resistive-type single-phase-to-ground fault occurrences triggered along one of the laterals when the network is operational. The obtained results demonstrated the capacity of an on-deck portable system to make an on-line accurate detection of transient faults in a complex network.