Partially Isolated Multi-Active Bridge DC-DC Converter with Bidirectional EV Charging Ports

There is a growing interest in multiport converters due to their ability to interconnect various energy sources and loads using reduced number of components. Regarding electric vehicle (EV) chargers connection, existing multiport solutions either lack scalability, featuring only one isolated charging port or the operation of ports depend on each other, complicating the converter control algorithm. This article proposes a partially isolated multi-active bridge (MAB) converter capable of connecting battery energy storage (BES) and an arbitrary number of EV chargers to the DC grid, aiming to resolve abovementioned problems. The proposed MAB converter requires 6N switches, whereas the conventional solution with independent 3-phase interleaved buck-boost and N DAB converters needs 8N+6 switches to connect BES and N EVs to the DC grid (N - odd number of EV charging ports). Simulation results have proven the ability of the converter ports to work independently in bidirectional operation modes for different BES and EV power levels.