Cascade linear extended-state observer active disturbance rejection control for DAB optimized with current stress

To enhance the disturbance rejection capability of the dual-active-bridge controller, this paper proposes an improved linear active disturbance rejection control scheme combined with current stress optimization. The system states are estimated in real time through a cascaded linear extended-state observer, based on extended phase-shift modulation. Load switching, input voltage variations, and power transmission fluctuations are treated as system disturbances, which are compensated for accordingly. This significantly improves the system’s disturbance rejection performance. Additionally, a reference derivative feedforward is introduced to optimize the tracking of the output direct-current voltage command, thereby improving dynamic performance. The experimental results obtained have provided definitive validation of the proposed control strategy, demonstrating its effectiveness and feasibility.