Multi-path routing based intelligent fault detection strategy for microgrids

The increasing integration of renewable energy sources (RES) and frequent topological changes in modern power systems pose significant challenges to overcurrent protection. These include non-selective tripping, protection miscoordination, and fault detection failures. This paper proposes a novel routing-based protection strategy that leverages multiple communication paths, classified as Main, Reserved, Source, and Reference, to enhance fault localization and coordination. Faults are mapped across routing areas (RAs), and information is exchanged via Intelligent Electronic Devices (IEDs) using the IEC 61850 protocol. Each path comprises Flow Areas (FAs) with neighboring IEDs that dynamically contribute to fault clearing based on their role in the path. Unlike conventional methods, the proposed strategy does not require changes to relay settings during faults. It ensures effective operation regardless of the location or penetration level of distributed generation (DG) units. Additionally, it addresses challenges related to fault current direction changes caused by topology shifts, and it enables IEDs to detect and learn new connection points in real time. The strategy is validated through simulations in ETAP, demonstrating improved selectivity, coordination, and reliability under diverse fault scenarios.