Analysis of Source and Load-side High Impedance Faults Using Stockwell Transform

High Impedance Faults (HIFs) occur due to the contact between an energized conductor and a high impedance surface. Because of the low amplitude fault current value and its random characteristics, there is no fully efficient solution for its detection. The vast majority of existing detection methods study only source side HIFs. To fill this gap, this paper analyzes the load side HIFs by using the current harmonic content, measured at the system substation, applying Stockwell Transform. The HIF is simulated through an impedance model using actual signals. The results reveal that low-frequency harmonics can be identified regardless of the fault location, mainly on the neutral than on the phase current. These conclusions can help researchers develop new methods to identify HIFs regardless of the scenario.