Faulty Phase Selection method for Microgrid with Inverter-Interfaced DGs

With the advent of smart protection devices, the utilities have started giving importance to single/double phase tripping for distribution system and microgrid, for which an accurate faulty phase selection is required. Incorporating more inverter-based distributed generation has increased the complexity for the protection devices to select the faulty phases accurately. The inverter-based distributed generations (DGs) show a different fault behavior compared to traditional synchronous-based machines, making the faulty phase selection difficult for the protection devices. This paper briefs the failure of some existing methods to identify the faulty phase and proposes a solution for the problem with a detailed explanation. The effectiveness of the method is tested on a 5-bus system with two photovoltaic distributed generations (DGs)and the results validate that the proposed method successfully selects the faulty phase.