Research on the Performance of Non-Linear Anti-Saturation Sliding Mode Active Disturbance Rejection Control in Synchronous Buck Converter Circuits

Abstract

To address the issues of slow convergence rate in traditional sliding mode control, which leads to slow response and low precision when applied in synchronous buck converters, a non-linear anti-saturation sliding mode active disturbance rejection control method is proposed. First, the traditional sliding mode surface function and conventional reaching law were modified by introducing non-linear and saturation functions to construct an optimal control law. Next, the fal function in the extended state observer and non-linear error feedback control law was replaced by the optimal control law, completing the optimization of the non-linear anti-saturation sliding mode active disturbance rejection control. This approach enhances dynamic response performance and improves disturbance rejection capabilities. Finally, a corresponding model was built on the MATLAB/Simulink simulation platform. The results show that the settling time is 138 µs, and the recovery time after a sudden load is 200 µs; experimental validation confirms that the proposed method exhibits faster adjustment time and stronger disturbance rejection capabilities when the speed command is changed under sudden load conditions.