Research on Dual optimization control method of DAB converter considering current stress and return power

As a key device for energy conversion and transmission in the Energy Internet, the Dual Active Bridge (DAB) converter will cause higher current stress and return power when its input and output voltages do not match, which affects transmission efficiency. So, a dual objective coordination optimization control method for current stress and return power of DAB converter based on Dual Phase Shift control (DPS) is proposed in this paper. Firstly, the phase shift control characteristics of DAB converter are analyzed, and the mathematical model of DAB converter under dual phase shift control is derived, to analyze the generation mechanism of current stress and return power in the converter. An optimization control model with the minimum current stress and return power as the objective function is established, and an internal and external phase shift ratio coefficient is introduced to ensure that the phase shift ratio value is within the constraint range. Secondly, the gradient descent algorithm is used to obtain the optimal phase shift ratio, and the output voltage feedback compensation control method is introduced to realize the dual optimization control. Finally, the simulation and experimental platform is built by Matlab/Simulink software and TMS320F controller. The results validate that the proposed optimization control method significantly reduces the current stress and return power.