An Intrinsic Faulty Feeder Selection Approach for Resonant Grounded Power Distribution Networks in Bushfire Prone Areas Using Zero-Sequence Current Ratio

A new low-computational zero-sequence current (ZSC) ratio-based method is proposed in this article that can expeditiously identify faulty feeders in resonant grounded power distribution networks with high impedance single line-to-ground (SLG) faults. The proposed fault detection mechanism utilizes the ZSC ratio of each feeder to determine the faulty feeder. In the proposed framework, SLG faults result in a sharp peak in the ZSC ratio where this peak is the opposite for faulty feeders while comparing with healthy feeders. The proposed approach is compatible with existing distribution networks having measurement devices of 2-kHz sampling rate which makes it particularly attractive for the power industry for the direct application with existing field devices. This approach is validated using a three-feeder distribution network with a resonant grounded substation with all analyses performed in MATLAB/Simulink platform while simulation results prove that the ZSC ratio-based method effectively identify faulty feeders over a range of fault impedances varying between 0.1 Ω and 80 k Ω depicting different fault inception angles.