Modularization structure for series-parallel connected converters

Power systems connected in series-parallel structure will be broadly applied. Input-parallel output-parallel (IPOP) configuration has been widely applied and other three configurations, input-parallel output-series (IPOS), input-series output-parallel (ISOP), input-series output-series (ISOS), have attracted increased attention recently. In recent years, literatures pay their focuses on various control methods to realize voltage/current sharing, and almost all of them just for single converter, resulting in without the advantages of power system connected by module converters. Three modularization structures are proposed for ISOP, IPOS and ISOS, respectively in this paper, which have the following features: a) basic converter in the connected system can operate in standalone mode; b) no extra controller is needed to regulate the input/output current/voltage distribution; c) fault-tolerant function is included. The simulation and experimental results are presented to verify the effectiveness of the proposed structures.