A High-Impedance Fault Detection and Faulty Feeder Selection Method Based on Zero Sequence Current Active Regulation Principle

Abstract

In distribution networks, the existing single-phase ground fault (SPG) protection technology faces challenges in reliably detecting high-impedance faults (HIFs). Moreover, the selection of faulty feeders is susceptible to the influence of distribution network parameters. To address these issues, a novel method for HIF detection and faulty feeder selection is proposed, which remains unaffected by asymmetrical distribution network conditions. The approach involves injecting current into the distribution network via an active inverter device. Then, a dynamic sensing criterion for ground faults is constructed based on the characteristics of the injected current and the change in zero-sequence current for each feeder. By adjusting the zero-sequence voltage, the difference between the zero-sequence currents of the faulty and healthy feeders is enhanced. Therefore, the amplitude characteristics of the zero-sequence current are then utilized to effectively identify the faulty feeder. The proposed method is validated through PSCAD/EMTDC simulation, demonstrating its capability to accurately identify HIFs and eliminate the influence of asymmetrical distribution network parameters on fault detection and faulty feeder selection.