A decoupling control method for multi-ports DC transformer

DC transformer (DCT) is a new type of intelligent power electronic device which uses power electronic switches and modern control technology to realize power conversion. Multi-ports DCT can directly interconnect multiple voltage level DC ports, and has a wide range of applications in DC distribution network. The equivalent circuit model of multi-ports DCT is studied in this paper, and the expression of transmission power is obtained. The small signal analysis method is used to get the control model. On this basis, a real-time control method is adopted, with the actual steady-state operating point replaced by the real-time calculation results of PI controller. The simulation and experimental results verify the correctness and effectiveness of the control method in this paper.