Distance Protection Performance in AC Power System With Back-to-Back Converter Interface

In renewables and asynchronous interconnection, converter interface plays a pertinent role for appropriate integration to the power grid. Nevertheless, implementation of these power electronic based converters introduces technical challenges considering an AC power system. In this study, the effects of converter interface on protection devices, specifically distance protection relays, have been investigated. An evaluation of the efficacy of these distance relays is performed considering abnormal conditions on the AC grid system interfaced with power electronic converters. Further, a three different case scenario is presented for a back-to-back converter that has been designed on MATLAB Simulink based on AL-FADHLI substation. Based on this investigation and observations, it can be emphasized that during a faulty condition, if the converters are the predominant power source at the interfacing point, the distance protection relays are negatively affected. Apart from this, no other associated technical complications are noticed to have an impact on the performance of these protection relays.