A Full-Bridge Switched Capacitor Hybrid Isolated Medium-Voltage DC Converter with Wide Input Voltage Range

In submarine DC transmission systems, there is an urgent need for a DC-DC converter with a wide input voltage and high step-down. The switched capacitor is widely used in high voltage situations due to its simple structure and high-power density, but its voltage regulated capacity is limited. Therefore, this paper proposes a full-bridge switched capacitor hybrid isolated medium-voltage DC converter with wide input voltage range. The fixed gain of the switched capacitor and the variable gain of the phase shifted full-bridge can accommodate a wide input voltage range, and the voltage can be adjusted by the phase shifted control method. Finally, an experimental prototype of 2 kV - <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$5 \text{kV} / 200 ~\mathrm{W}$</tex> is established to demonstrate the wide range voltage ability of the proposed topology.