A Modular Multi-port DC/DC Converter for DC Grid

DC power grid provides a solution for long-distance transmission and wide-area consumption of large-scale renewable energy. The DC/DC converter is an important device in the DC power grid, which can interconnect multiple DC lines of different voltage levels. This paper proposes an easy-to-implement modular multi-port high-voltage high-power DC/DC converter. The proposed topology does not require large-capacity transformer or large inductance filter on the output DC side, and it has fault current suppression function as well as strong engineering applicability. In this paper, the control strategy of the topology and the analysis of the DC short-circuit fault characteristics are presented. The feasibility and effectiveness of the topology, control strategy and protection method are verified by simulation.