Design of Multi-Port LVDC-SOP Based on Four-switch Converter

With the development of distributed generation and energy storage which have DC characteristics., more attention was paid to the DC microgrid. But there are problems such as insufficient consumption and low energy utilization due to the randomness and intermittency of renewable energy. A wider range of resource integration after the interconnection of adjacent DC microgrids can solve this problem. For the interconnection and power scheduling among multiple DC microgrids., a multi-port low-voltage DC soft open point (LVDC-SOP) is designed in this paper. Operation mode of the multi-port LVDC-SOP can flexibly transfer among current control., voltage control and droop control modes. The four-switch buck-boost (FSBB) converter is adopted as port converter which is suitable for wide range voltage conversion and convenient to achieve the isolation of fault ports. The proposed topology and control strategy are verified through the simulation and experiments on a 48V/4 kW multi-port LVDC-SOP prototype.