Fault Diagnosis Method for Single-Phase-to-Ground Faults Based on Phase-to-Phase Current Fault Components in Distribution Networks

Accurate diagnosis of single-phase-to-ground (SPG) faults in distribution networks is essential for rapid fault isolation and reduced power interruptions. Existing approaches often address only one aspect of fault diagnosis, suffering from low reliability, heavy communication requirements, and high investment costs. To overcome these challenges, this paper presents a comprehensive fault diagnosis method based on phase-to-phase current fault components (PPCFC). The fault characteristics of PPCFCs are firstly analyzed on both the substation and feeder sides, taking into account the practical configuration of current detection devices. The results show that, in faulty feeders and sections, the fault-phase-related PPCFCs are significantly larger than the healthy-phase-related ones, while in healthy feeders and sound sections, all three PPCFCs remain close to zero. The PPCFCs are then calculated with consideration of possible triggering delays under high impedance faults, and their amplitude features are extracted. Based on this analysis, a fault phase and faulty feeder identification method is developed using PPCFCs from a single feeder at the substation side. In addition, a distributed location strategy is proposed, which employs local indicators to accurately determine the fault section via simple binary communication. Extensive experiments confirm its effectiveness and practicality.