Assessment of impedance based fault locator for AC micro-grid

This paper proposes an impedance-based fault location determination scheme for the 3-phase micro-grid. The paper describes how voltage and current data during a fault event can be leveraged to accurately locate a fault in the micro-grid including distributed generation (DG). The proposed method uses voltage and current measurements from both ends of the line section in order to determine the fault location. This method is devised in such a way that it evades the requirement of fault type identification by using only one fault location equation. The method is applicable to all types of shunt faults. In the proposed formulation of fault location, the effect of mutual inductance and capacitance of distribution line is also considered. The method is tested on a simulated medium-voltage (MV) micro-grid with doubly fed induction generator (DFIG) and permanent magnet synchronous generator (PMSG) wind turbines connected to specific nodes. The test results indicate that the proposed fault locator can reliably locate faults in the micro-grid with high accuracy.