Improved linear active disturbance rejection control for double active bridge series resonant converter with high voltage gain

Abstract

The double active bridge series resonant converter (DABSRC) has become a research hotspot in both scientific and engineering fields due to its high efficiency and high voltage gain characteristics demonstrated in energy storage systems and smart grid systems. In this paper, an improved linear active disturbance rejection control (LADRC) algorithm is proposed to improve the dynamic response performance of the DABSRC. Compared to the existing LADRC algorithms, the primary enhancements of the proposed LADRC involve optimizing the feedback control law and the introduction of error proportion in the linear extended state observer (LESO). These modifications effectively reduced the estimation error of perturbation of the LESO and consequently enhanced the stability and dynamic response performance of the converter. In the paper, simulations and experiments are conducted to investigate the performances of a DABSRC by using three different control strategies, that is, the PI controller, the traditional LADRC, and the improved LADRC proposed in this paper. The experimental results proved the feasibility and correctness of the improved LADRC strategy. The proposed algorithm is not only applicable to the DABSRC but also suitable for other converters to improve the dynamic response performance.