Design of high-capacity bidirectional triple-three-phase DC-DC converter and four-mode control strategy

Distributed generation systems require high-capacity converters that enable bidirectional energy flow to connect energy storage units and enhance system stability. To address this issue, this paper proposes a triple-three-phase DC-DC converter topology and a four-mode control strategy to achieve smooth voltage buck-boost conversion control. First, the operating modes of the energy storage unit under different conditions are analyzed. Then, a triple-three-phase DC-DC converter is proposed, and the working principle of the topology during the voltage conversion process is explained. Finally, a four-mode control method is proposed to improve the bus voltage stability during the voltage buck-boost conversion. The feasibility and effectiveness of the proposed converter topology and control method are verified through an energy management platform.