Low Voltage Ride Through Control for Grid-connected Inverter Based on Second Order Generalized Integrator under Unbalanced Faults

This paper proposes a low-voltage ride-through (LVRT) strategy for grid-connected inverter in order to compensate both positive and negative-sequence reactive power to improve power quality under voltage sag conditions. LVRT is becoming mandatory in low-voltage system due to both power-quality consideration and security requirement. This study is part of the Power Station project. This paper analyzed the fault characteristics of a grid under different voltage sag operating conditions. To prove the effectiveness of the proposed control, simulation tests have been performed. Based on the results achieved, good operation of the considered voltage sag control of system has been confirmed.