Linear Active Disturbance Rejection Voltage Control of Dual Active Bridge Converter Based on Model Compensation

Introduction: In microgrid systems, multiple disturbances can easily lead to output voltage instability in the Dual-Active-Bridge (DAB) converter. Methods: This paper proposes a linear active disturbance rejection control strategy based on model compensation. First, a mathematical model of the Dual-Active-Bridge (DAB) converter under extended phase-shift modulation is established. By introducing compensation information for external disturbances, the burden on the linear extended state observer is reduced, thereby improving the disturbance rejection performance and dynamic response speed of the active disturbance rejection controller. Meanwhile, control parameters are tuned using Bode plots, and the Lagrange multiplier method is employed to minimize the peak inductor current. Finally, a DAB experimental platform is built to validate the proposed control strategy. Results: Experimental results show that compared with PI control and conventional linear active disturbance rejection control, the linear active disturbance rejection controller with model compensation information exhibits better performance under disturbances such as load switching, input voltage variations, and output voltage reference step changes. Meanwhile, compared with single- phase shift modulation, the proposed control strategy reduces the peak inductor current. Discussion: The proposed control method can effectively improve the disturbance rejection capability of the DAB converter system. However, the experimental environment in this study is relatively ideal, and further research is needed to investigate the performance of the proposed control method under various extreme and complex conditions. Conclusion: The linear active disturbance rejection controller with model compensation information effectively maintains output voltage stability across various operating conditions, demonstrating excellent dynamic and steady-state performance.