Fault location in microgrids: A communication-based high-frequency impedance approach

Abstract

This paper proposes a novel method to locate faults in an AC-meshed microgrid. To this end, a set of features is first extracted and selected from the measured signals and fed to a Support Vector Machine (SVM) to detect the occurrence of fault. Then, the Distributed Generator (DG) with the lowest amount of fundamental voltage, which is the closest one to the fault, injects an appropriate voltage/current harmonic. As the faulted section has the lowest impedance value from the Point of Common Coupling of the DG, the harmonic current of the corresponding line has the highest value. Based on this fact, the first candidate DG sends a notification signal to the second candidate DG, in which the fault occurs between them. Finally, the impedances in the injected frequency are measured from these two DGs and fed into a multi-class SVM to locate the faulted line. The proposed method has the ability to locate faults for islanded and grid-connected microgrids with variable configurations. Real-time simulation results are taken by OPAL-RT to show the effectiveness of the proposed method in the meshed microgrid.