Research on the Output Voltage Sharing Control Strategy of Input-Parallel Output-Series Modular DC/DC Converter

In this paper, a distributed control strategy for multi-module Input-Parallel-Output-Serial (IPOS) DC-DC converter system is investigated to address the problem of unsatisfactory voltage homogenisation on the serial output side due to sudden load changes during operation, which affects the normal operation of the system. Based on the double closed-loop control strategy, a virtual DC motor control is introduced to simulate the damping and inertia characteristics of the virtual DC motor and introduce them into the system, so that the IPOS system can achieve voltage sharing on the output side and the total output voltage can remain stable during sudden load changes. The stability and reasonableness of the proposed control strategy are sharing by small-signal modelling and Laws' criterion, and the feasibility of the control strategy and its voltage sharing and sharing effects are simulated and verified on the Matlab/Simulink platform.