Sliding Mode Control of Buck Converter Based on Disturbance Observation

Aiming at the problem of matched and unmatched disturbances in Buck converter systems, this paper proposes a full-order sliding mode control strategy based on a disturbance observer. Firstly, the mathematical model of the Buck converter with multiple disturbances is established. Secondly, two disturbance observers are designed to estimate the matched and unmatched disturbances, respectively, in order to track the disturbance signals and mitigate the effects of various uncertainties on the system. Next, a full-order sliding-mode control strategy based on the disturbance observers is proposed to enhance the dynamic performance of the controller and reduce steady-state error. Finally, the stability of the proposed controller is proved using Lyapunov theory. Simulation results demonstrate that the proposed method effectively suppresses system disturbances, resulting in faster convergence and higher tracking accuracy.