Fault Ride-Through Capability with Mutual Inductance in Low-Voltage Single-Phase Microgrid

Abstract

Improving the microgrid fault ride-through capability and enhancing the transient performance of microgrid operation due to voltage sags is of great importance. This paper investigates the ride-through capability and feasibility of integrating a mutual inductance between the main grid and the microgrid under short circuit condition. The fault ride-through capability of the microgrid DGs is examined by placing the mutual inductance at PCC to suppress the fault current and to maintain the microgrid grid connected. This inductance requires no control to operate in which the sudden current increase is the key point of its operation. The microgrid DGs can operate successfully in grid-connected mode without reactive power support during the voltage sag duration. The effectiveness of the inserted mutual inductance has been validated considering two case scenarios of the microgrid power flow condition. The proposed methodology shows promising results, in which it confirms the applicability of the mutual inductance in riding through the fault current and maintaining the microgrid DG operation in the grid-connected mode. SimPowerSystems and PLECS toolboxes of Matlab/Simulink software are utilized to implement the proposed work.