Adaptive Hybrid Tripping Microgrid Protection Strategy With Embedded Hardware Validation

This paper proposes an adaptive hybrid-tripping-based protection strategy for microgrids (MGs) that enables a fast and reliable response to faults by leveraging phase voltage and current measurements from relay locations. The protection coordination problem was addressed by optimizing the relay settings for different MG operating scenarios, ensuring proper coordination between the primary and backup relays. Comprehensive performance evaluation using PSCAD simulations demonstrated that the proposed protection scheme operates with 50% of faults cleared within 41.5 ms, while 90% of cases are cleared within 530.8 ms across various fault conditions in both grid-connected and islanded operating conditions. The backup relays exhibited a minimum trip time of 230 ms and a median trip time of 299.6 ms, while the coordination time intervals remained within safe margins (50% of cases maintaining a margin of 246.7 ms), ensuring selectivity. Moreover, real-time hardware-in-the-loop (HIL) tests using TMSF28335 microcontrollers validated the scheme’s practical applicability, showing a strong correlation between simulated and experimental results. The mean difference between the simulated and experimental trip times was 29 ms, with maximum deviations below 7.2% (64 ms) and a minimum deviation of 5 ms. The results confirm the effectiveness of the proposed strategy in reducing tripping times while maintaining coordination, making it a promising solution for both islanded and grid-connected MG operating modes.