High-Voltage DC/DC Converter Topology With Active Filtering Arms

The rapid growth of renewable energy installation promotes the development of high voltage direct current (HVdc) links for energy integration and transmission. To meet the future needs of HVdc grids, high-voltage dc–dc converters are needed to interconnect HVdc links with different voltage levels. This article proposes a high-voltage active filtering dc–dc converter composed of only one energy buffering arm to transfer energy and two active filtering arms for dc current continuity. This topology features low cost and small footprint. The circuit configuration, operation principle, parameter design, and control strategies are presented. Particularly, the decoupling control is proposed to solve the coupling among energy balance control of different arms. Both the simulation case of 100 MW, 200 kV/320 kV, and downscaled experimental results of 1.5 kW, 150 V/300 V are provided to demonstrate the validity of the proposed topology. Furthermore, a series of dc–dc topologies with active filtering principle are derived and evaluated.