The enhanced inverse droop control strategy with voltage feed-forward adjustment for series input parallel output DC–DC converters

As a high-efficiency DC-DC converter, the dual active bridge (DAB) converter can be connected in series on the input side to improve the withstand voltage capacity and in parallel on the output side to enhance the current processing ability. This configuration helps meet the energy storage system's demand for efficient energy conversion. Sharing input voltage and output current between modules is crucial to ensure the normal operation of the series input parallel output system. To overcome the limitations of the traditional inverse droop control strategy, which fails to achieve voltage and current sharing and zero steady-state error simultaneously, and to enhance the adaptability and stability of the system in response to input voltage and load changes, as well as improve the dynamic performance. The proposed strategy combines the inverse droop control strategy with correction and the inverse droop strategy of fixed voltage feed-forward. It integrates a PI correction module with real-time input voltage changes and conducts stability analysis. A simulation model of a series input parallel output system with two DAB modules is developed using MATLAB simulation software to verify the control strategy. The simulation results confirm the effectiveness of the proposed control strategy.