Abstract：An optimal control strategy based on extended phase shift（EPS）modulation was adopted to

address the problems of high current stress，slow dynamic response and input voltage imbalance in the input-seriesoutput-parallel dual active bridge（ISOP-DAB）converter. By constructing a functional relationship between the scalarised transmission power and the shift ratio，the optimal internal shift ratio in the full power range was solved with the help of the KKT condition. The optimal external shift ratio was solved by combining the state-space

expression of the output voltage with the model predictive control，and the error correction factor formed by the

superposition of the input voltage loop and the output voltage loop was introduced to improve the dynamic tracking performance of the system and achieve the balanced control of the input voltage between modules. Simulink results show that this strategy can effectively reduce the current stress，shorten the dynamic response time，suppress the input voltage deviation，and improve the transfer efficiency of the converter under sudden load changes and input voltage perturbations.

        Key words：extended phase shift（EPS）；input-series-output-parallel dual active bridge （ISOP-DAB）

converter；model predictive control（MPC）；current stress；transmission efficiency

     Format Citation:严伟，王金梅，关雪涛,等. 基于扩展移相的ISOP⁃DAB变换器优化控制策略[J].电气传动,2026,56(10):23-31. YAN Wei，WANG Jinmei，GUAN Xuetao,et al. Optimal control strategy for ISOP-DAB converter based on extended phase shift [J].Electric Drive, 2026,56(10):23-31