Energija, ekonomija, ekologija, 1, XXVIII (2026) (16-23 стр.)
АУТОР(И) / AUTHOR(S): Aleksej Zilovic 
, Luka Strezoski , Chad Abbey
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DOI: https://doi.org/10.46793/EEE26-1.16Z
САЖЕТАК / ABSTRACT:
The increasing penetration of inverter-based distributed energy resources (IBDERs) in microgrids significantly alters short-circuit behavior, often resulting in fault currents that are comparable to nominal load levels. Combined with frequent transitions between grid-connected and islanded modes, this renders conventional overcurrent protection (OCP) schemes unreliable, leading to mis-operations, loss of selectivity, and delayed fault clearing. Additionally, Fault Ride – Through (FRT) requirements allow IBDERs to sustain limited current contribution for a defined time window before tripping, which further complicates protection settings.
This paper introduces an adaptive OCP framework that dynamically adjusts protection thresholds based on both the microgrid operating mode and time intervals aligned with expected IBDER current response. By incorporating FRT-driven time segmentation, the proposed approach allows reliable discrimination between transient and permanent faults, while preserving system stability. Preliminary simulation case studies demonstrate promising improvements in detection sensitivity and coordination when compared to fixed OCP settings, suggesting a viable foundation for implementation in future real-time microgrid protection schemes.
КЉУЧНЕ РЕЧИ / KEYWORDS:
Overcurrent protection, IBDER, Microgrids, FRT requirements, Adaptive protection in microgrids
ПРОЈЕКАТ / ACKNOWLEDGEMENT:
Artificial intelligence tools, specifically ChatGPT and Grammarly, were used to improve the English language and grammar of this manuscript.
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