Analysis of Imbalance in Input-Series Output-Parallel Configuration of Series Resonant Converters

This paper analyses the power imbalance in input series output parallel (ISOP) configurations of series resonant converters (SRC), which are crucial for MVDC to LVDC conversion where electrical isolation and bidirectional operation are required. The dual active bridge (DAB)-based ISOP structure presents a promising solution, but it requires careful management of power distribution among modules to prevent imbalances. This study provides analysis on imbalance among SRC modules for a partial power control method, which contributes to reducing communication costs and complexity by minimizing the number of active control modules. Experimental results with two prototype SRC modules validate the theoretical analysis, demonstrating that power imbalances are negligible in the ISOP configuration.