To address the issues of low integration

complex control architecture

sluggish dynamic response under complex operating conditions

and poor control-system robustness of conventional multi-port converters

a Buck/Boost-CLLLC resonant three-port converter with shared bridge arms is proposed. Furthermore

an improved sliding mode active disturbance rejection control (ISM-ADRC) strategy is developed for the proposed converter. First

the fundamental operating principles and voltage gain characteristics of the proposed converter are analyzed

revealing that load disturbances have a significantly impact on system stability. Second

an ISM-ADRC strategy integrating a continuous sliding mode control scheme with a state extended observer is designed to enhance the system’s disturbance rejection capability while accelerating its dynamic response. Finally

comparative dynamic and steady-state experiments under different control strategies are conducted using both simulations and a laboratory prototype. Experimental results demonstrate that

under ISM-ADRC

the prototype reaches a stable state within only 9 ms. Moreover

the output voltage overshoot under load step changes is reduced by 70%

and the dynamic response time is shortened by 62.5%. These results validate the effectiveness and feasibility of the proposed control strategy.