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Since the penetration level of the inverter‐based distributed generations (IBDGs) into microgrids (MGs) is increasing, the protection issues of such networks have become more challenging. The present work aims to design a protection framework for fault detection and classification in IBDG dominated MGs. In the proposed approach, the current waveforms measured from one end of the protected lines are processed using superimposed components. Then, the faults are identified using the Euclidean distance concept. A Pearson correlation coefficient‐based approach is also developed to characterize the faulty phases in the proposed fault classification unit. Furthermore, an auxiliary index is defined to discriminate load change conditions from the faults. In addition to being simple and efficient, the proposed technique is highly capable of functioning in different MG operating modes and configurations without changing its settings. Also, it demonstrates robust performance against IBDG impacts, noises, and stimulating fault scenarios. To assess the scheme proficiency, a modified IEEE 15‐bus system with highly penetrated IBDGs is simulated. The results confirm the quickness and high accuracy of the proposed technique. Moreover, the method is validated in an experimental laboratory test bench. Finally, the superiority of the method is confirmed by a comparative study with other recent methods.

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Summary Connection of distributed generations (DGs) to distribution networks changes their radial construction to mesh type and increases fault current level. In order to prevent over current relay tripping in case of out‐of‐zone faults, direction of faults must be determined. On the other hand, fault current limiters (FCLs) are a suitable technique to reduce the issue of fault current increasing. In this paper, it is confirmed that operation of FCLs affects voltage and current signals, drastically. Since fault direction is detected by directional relays using these signals, hence, FCLs can affect the performance of the relays. In the other hand, if the added DG is a wind turbine, it may affect the directional relays performance due to intricate fault behavior of wind turbines. To investigate the mentioned hypothesis, some of directional relaying algorithms are evaluated in presence of wind turbine and FCL.