Active Fault Current Limitation for Low-Voltage Ride-Through of Networked Microgrids

With the continuously increasing penetration of networked microgrids (MGs) on local utility grid (UG), MGs face challenge to avoid system fault currents during low-voltage ride-through (LVRT). To solve this challenge, an active current limitation (AFCL) method is proposed with three parts: 1) a novel phase angle adjustment (PAA) strategy conducted relieve impact output current; 2) injection (CI) for LVRT formulated fit function PAA; 3) converter generation (CCG) developed achieve better voltage support ability by considering network impedance characteristics. The AFCL applied back-to-back converter, as connection interface between and UG. Extensive tests pertinent results have verified improvements performance, while does not increase amplitude current.