Volatility Diagnosis in Phase-to-Phase Fault Detection for Branch Across Wire Faults

High Impedance Faults (HIFs) are disturbances that can lead to bush fires. This work presents physical and electrical phenomena associated with ph-to-ph faults for a range of tree species. Physical ignition phenomena of a tree branch under a ph-to-ph fault scenario are analysed to identify stages of ignition. A methodology, based on the rate change of the RMS current and zero-crossings in the averaged RMS current, has been applied with 96.12% accuracy to identify ignition stages. The key contribution is the proposed volatility detector for detecting RMS current volatility during a HIF event. The concept of relative volatility is applied to detect signatures of HIFs and branch charring in the RMS current data stream with respect to the stream itself.