Abstract: With the high proportion of new energy integration, the dual active bridge DC-DC converter in DC microgrid systems needs to be optimized to address issues such as voltage fluctuations, slow dynamic response, and reduced efficiency during system disturbances. This article proposes an optimized control strategy that combines sliding mode control and minimizing current stress under extended phase shifting, which improves system dynamic response performance while enhancing efficiency. Considering the chattering phenomenon of traditional sliding mode control, the super-twisting sliding mode algorithm is adopted to eliminate this phenomenon and improve the control accuracy and performance of the system. This article conducted simulations and designed and built an experimental platform. The experimental results show that the control system has good dynamic and steady-state performance when the input voltage suddenly changes, the load switches and the reference voltage changes. At the same time, it can effectively reduce current stress and achieve multi-objective optimization of the system. The feasibility and effectiveness of the proposed control strategy have been verified through simulation and experiments.