Short-Circuit DC Current Estimation of Hybrid Energy Storage Systems

DC microgrids have become a valuable alternative to AC microgrids for industrial and shipboard power systems due to the DC nature of most energy storage systems, which are increasingly used in these applications. However, integrating this technology introduces new protection issues. The unidirectionality and the very high derivative of DC fault currents discharging from the capacitor are the main challenges arising from adopting DC technology. Therefore, this study focuses on the short-circuit response of energy storage systems and their power electronic converters. Several energy storage sources are modeled using manufacturers datasheets, and their short-circuit responses are analyzed. The short-circuit responses of each energy storage system are simulated and compared with an analytical method. A parametric study is then performed, varying selected parameters to examine their influence on the short-circuit response.