Dual-Integral Sliding Mode Control for Dual-Active-Bridge DC-DC Converter Based on Dual-Phase-Shift Control

To tackle the issue of poor dynamic performance of dual-active-bridge (DAB) DC converters in DC microgrid systems under disturbances, this paper proposes a dual-integral sliding mode control strategy based on dual-phase-shift modulation. First, the mathematical model of power transmission for the DAB converter under dual-phase-shift modulation is analyzed. Then, a reduced-order model of the DAB converter is established based on the power transmission mathematical model. Using this reducedorder model, a dual-integral sliding mode controller is designed to work in conjunction with the internal phase-shift ratio $D_{1}$ to generate the external phase-shift ratio D<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</inf>, which regulates the converter’s output voltage. Finally, simulation results verify that the converter demonstrates excellent dynamic performance during load switching and input voltage transients.