Distortion-Based Detection of High Impedance Fault in Distribution Systems

Detection of the high impedance fault (HIF) in distribution systems is significant for power utilization safety. In addition to low currents, traditional approaches are invalid detect HIFs also due diverse characteristics, including slight HIF nonlinearity during weak arcing process, distortion offset caused by lag heat dissipation, and interference background noise. This paper proposes a distortion-based algorithm improve reliability detection under various conditions. Firstly, challenges brought diversity distortions explained according field experiments 10 kV real-world system. classified into five types their current waveforms. Secondly, definition interval slope introduced describe waveform distortions. The extracted combining methods linear least square filtering (LLSF) Grubbs-criterion-based robust local regression smoothing (Grubbs-RLRS), so that different conditions can be uniformly described. Thirdly, an proposed judge features presented slope, distinguish from non-fault Finally, security thoroughly analyzed with simulated obtained IEEE 34-bus 123-bus systems. Results show improvements comparisons other advanced algorithms.