Micro grid architecture for line fault detection and isolation

One of the major problems power grids system face today is the inability to continuously deliver power at the consumer side. The main reason for this is the occurrence of faults and its long term persistence within the system. This persistence of faults causes the cascading failure of the system, thereby adversely affecting the connected loads. Traditional methods of fault isolation cause the shutdown of power to a large area to maintain the system stability. Today, localization of faults and its isolation is doing manually. Therefore, a localized fault recovery mechanism is very essential to maintain the system;s stability after the occurrence of a fault. In this paper, we have developed fast fault detection and isolation mechanism for single phase to neutral line fault in a three phase islanded micro grid scenario. The fault detection and isolation during the islanded operation mode of a micro grid is very critical, since bidirectional power flow is present. The fault detection mechanism we developed can detect and isolate the fault within a few milliseconds and localize the fault within a two second delay for both in single and bi-directional power flow scenarios. The proposed system is capable of locating the exact faulted segment with the aid of the communication network integrated into the power grid. The implemented system was tested with different ranges of fault current and the analysis showed that the proposed system could localize the fault with less than a two second delay.