High Impedance Fault Detection based on Stockwell Transform

A high impedance fault (HIF) detection method is proposed in this paper. Several parameters are extracted using the Stockwell transform, which is a relatively new multi-resolution tool with the ability to provide good resolution on both time and frequency domain, simultaneously. Those parameters are used to identify a HIF occurrence and distinguish it from other common disturbances such as capacitor banks switching, feeder energizing and solid faults. Two databases are used to validate the method, one with simulated data and one with real HIF oscillographic records, obtained from field experiments. A brief analysis of parameters behavior is also presented, since it is necessary for method's development. Results show the method is able to detect HIF on both simulated and real data in viable time, using only the substation as observation point. Also it can distinguish the fault from other tested disturbances.