Aiming at the problem of accelerated battery aging due to high current stress in DC microgrid energy storage system

the peak current optimization of DAB converter under double phase shift modulation is investigated. Firstly

the commutation process and operating characteristics of the DAB converter under double phase-shift modulation are analyzed. Then

in order to reduce the current stress during voltage mismatch

the study takes the peak current expression as the objective function

constructs a mathematical model using the KKT condition

and solves the optimal shift ratios for the four operating modes of the Buck mode under double phase-shift modulation. The optimal shift ratio is substituted into the boundary conditions of each mode

and the local optimal power transfer range of current stress is derived. By comparing the magnitude of the current stress of the four modes

the current stress optimization scheme suitable for the full power range adaptive ZVS mode is constructed to ensure that the current stress reaches the optimal level in the full power range. Finally

it is experimentally verified that the adaptive ZVS mode modulation has less current stress compared with SPS modulation and full ZVS mode modulation during voltage mismatch operation.