A High-Robust Control Scheme of DAB Dc-Dc Converter for DC Grid with Different Loads

In DC grids, various loads such as resistive loads, constant power loads (CPL), and constant current loads (CCL) can be present. CPL and CCL usually impact the grid's stability, but most existing methods primarily focus on resistive loads. To address this, a high-robust control (HRC) scheme is proposed for the dual-active-bridge (DAB) dc-dc converter, achieving an ultrafast dynamic response within two switching periods under different load changes. Moreover, the first-order behavior of the DAB converter is explored and verified for the first time, highlighting its potential for ultrafast dynamics. Furthermore, the design of the control parameter is analyzed. Finally, simulation results validate the first-order characteristics of the DAB converter, while experimental results confirm the excellent performance of the proposed HRC scheme.