Investigation of fault ride-through capability of AC/DC hybrid microgrids during AC network faults

Abstract

This paper investigates the fault ride-through (FRT) capability of an AC/DC hybrid microgrid during AC network faults. AC/DC hybrid microgrids received immense attention in recent years due to the trend of using a separate DC bus for DC sources and loads connected to the microgrid. However, the fault ride-through (FRT) performance of the AC/DC hybrid yet to be fully explored. In particular, the interlinking bidirectional converter performance and DC bus stability are very important for the FRT performance of the entire AC/DC hybrid microgrid. In this study, FRT support strategies are implemented for each distributed energy resource (DERs) within the microgrid, and the interlinking bidirectional converter facilitates the power flow between the AC and the DC microgrids. Results indicate that by employing DERs equipped with FRT capability, it is possible to improve the DC microgrid FRT performance, but negligible improvement can be seen at the AC microgrid. Therefore, further investigations are required to improve the FRT support services provided by the bidirectional converter to enhance the FRT capability of the entire AC/DC hybrid microgrid.