Modular Multilevel Resonant DC Converter with Reduced Submodule Capacitance

Modular multilevel DC-DC converter is widely adopted in medium-voltage-to-low-voltage DC power conversion scenarios, while it suffers from the large footprint caused by large submodule capacitors and filter components. Hence, this paper proposes a compact modular multilevel resonant DC converter with an alternative capacitor structure, which improves the equivalent operation frequency of MMDC and reduces the submodule capacitors and filter components dramatically, as does the volume/weight. Based on the discussion on operation principle, the design procedure and control strategy are presented, which are verified with simulation.