Optimal control strategy of three-port DC energy router based on TCM modulation

Abstract

Three-port DC/DC converter can be used in the DC micro-grids as an energy router. To achieve higher efficiency, the optimal modulation scheme of triangular current mode modulation (TCM) is proposed, which considers the current stress and system losses. First, the operation mechanism of TCM is analyzed. The power transmission characteristic, voltage and current characteristics of each component are analyzed. Appropriate voltage stability control strategy is designed. Then, the simulation model of three-port energy router is built. And the characteristics of load power fluctuations or power flow switching are analyzed. The results show that, the power flow and dc bus voltage between different ports can be effectively controlled. Finally, the effectiveness of the proposed TCM strategy applied to the triple active bridge (TAB) converter is validated by using MATLAB/Simulink.