Detection of Faulty Feeders and Phases in Resonant Grounded Power Distribution Networks for Bushfire Prone Areas Using Measurements From Existing Field Devices

This article proposes a framework to detect faulty feeders and phases in resonant grounded distribution networks in bushfire-prone regions. It utilizes the filtered energy ratio (FER) of distinct feeders to identify faulty ones, which is determined by comparing individual and total feeder energies after filtering through an RC filter. The normalized energy ratio uses the equivalency of faulty feeder energy to total energy to discriminate between faulty (1) and healthy (0) feeders. The current ratio, which is calculated from phase current and total phase currents, is used to detect faulty phases where the direction of the current ratio facilitates faulty phase differentiation. All existing methods are limited to a minimum sampling rate of 5 kHz while confining for faults up to 10 $\text{k}\Omega $ though current measuring equipment can sample data at 2 kHz and fault impedances exceed this threshold. The purposed approach excels at detecting single line-to-ground faults in diverse impedance scenarios with a 2 kHz or even lower/higher sampling rate. The approach has been rigorously validated through simulations with fault impedances ranging from $0.1 \Omega $ to 0.1 $\text{M}\Omega $ along with some experiments under a certain scenario.