A Fast Dynamic Response Control Method for DAB Converters in Microgrids

To address the issues of significant dc bus voltage and load fluctuations, as well as unstable power transmission in dual active bridge (DAB) converters within dc microgrid systems, this article proposes a segmented gain adjustment method based on multiplicative feedforward control (MFC-SGA). First, considering both steady-state and dynamic performance of DAB converters, two hybrid optimization control methods are proposed, and their advantages and disadvantages in terms of circuit parameter sensitivity and controller gain are analyzed. Second, to overcome the limitation of multiplicative feedforward control in light-load conditions due to restricted controller gain, the MFC-SGA method is introduced to enable adaptive parameter adjustment. Finally, an experimental prototype is built. Experimental results show that the MFC-SGA method is independent of inductance accuracy. When the operating condition changes, compared with the traditional method, the settling time is shortened by 60–83% and the overshoot is reduced by 37.5–62.5%; especially in light-load mode (10% of rated current), the dynamic response speed is improved by 68.75% compared with the MFC method, and the settling time is reduced from 32 ms to 10 ms. The experimental results verify the feasibility and effectiveness of the proposed method.