This study presents an analysis of different DC-DC converter architectures and topologies suitable for solid oxide fuel cell (SOFC) systems operating in electrolysis and fuel cell modes. The goal is to determine the most suitable converter design based on efficiency and gravimetric power density. The two operating modes of the SOFC are illustrated, and the requirements for rise/fall times and maximum allowable ripple current are discussed. Several converter topologies, including three-level multi-channel buck, three-level four-switch buck-boost, and buck with active filter, are evaluated. The design considerations, including inductor values, switching frequencies, and current waveforms, are discussed for each topology. Finally, a multi-objective design optimization procedure is performed to compare the efficiency and weight (gravimetric power density) of the considered converters.
