Coordinated Ground Fault Suppression Using Feeder-Side Power Router with Active Voltage Regulation Considering Line Impedance

With the expansion of cable-based distribution networks and the growing integration of power electronic devices, conventional arc suppression methods face increasing difficulty in addressing the complex characteristics of single-phase-to-ground faults. Additionally, control inaccuracies caused by line impedance significantly limit the effectiveness of existing active suppression technologies. To address these challenges, this paper proposes a coordinated ground fault suppression strategy for distribution networks that accounts for line impedance, by coordinating a substation-side arc-suppression coil (ASC) with feeder-side power router (PR) devices. First, the operational principles and coordination mechanism of the substation-side ASC and feeder-side PR are analyzed, and a capacity allocation scheme is developed to ensure efficient equipment utilization during the arc suppression process. Next, the influence of line impedance on arc suppression is examined under various PR installation positions and feeder ground fault scenarios. To overcome the limitations of conventional methods, a dual-impedance feedforward compensated active voltage arc suppression (DFC-AVAS) strategy is proposed. This method improves fault point voltage suppression by accounting for line impedances between the feeder-side PR and the substation bus, as well as between the substation bus and the fault point, within the zero-sequence voltage feedforward loop. Finally, the effectiveness of the proposed method is validated through simulation.