Short-circuit calculation of droop-controlled islanded AC microgrids with virtual impedance current limiters

In this manuscript, a novel Δ-circuit approach is proposed, which enables the fast calculation of fault currents in large islanded AC microgrids (MGs), supplied by inverter-based distributed generators (IBDGs) with virtual impedance current limiters (VICLs). The concept for limiting IBDGs has gained interest research community recent years, due to strong advantages it offers. Moreover, an efficient and easy-to-implement approach, widely applied, short-circuit transmission distribution networks. However, traditional Δ-circuit, its form, not applicable MGs, particular characteristics such networks, e.g., absence slack bus. To overcome issue, proposed paper, following distinct features: (a) precise simulation (b) computational performance, (c) generic applicability all types faults single-line, 2-line or 3-line faults, (d) simple extension other DG modes, latched limit strategy etc. (SCC) method validated through time-domain software Matlab Simulink, 9-bus 13-bus MG. performance further tested modified version IEEE 8500-node network.