Practical Demonstration of High-impedance Fault Detection Technology in MV Distribution Network

Abstract

In MV distribution network, theprobabilityofsingle-phase-to-groundfaultisashighas60% to 80%. Some of these faults can cause personal electric shocks or fire incidents, such as broken wires and wires discharged through the branches. They are classified as high-impedance faults (HIF). The existing faulty line selection and protection devices cannot reliably detect HIF. To ensurespublic safety，it is necessary to develop new technologies for HIF detection in distribution network.This article focuses on these issues, and introduces the research and demonstration of HIF detection technology in Fujian electricity Power Co. Ltd. In addition, artificial grounding tests were conducted to simulate ground faults through resistance, spherical gap, devices, wet earth and dry earth.