Abstract In order to solve the problems of output voltage overshoot and slow error convergence in Buck digital power supply under large dynamic load range, a method combining second-order sliding mode controller with linear tracking differentiator is proposed. The second derivative of voltage error is used as an additional sliding surface to improve the order of the controller and optimize the dynamic performance of the controller. At the same time, aiming at the problem that the traditional differentiator is easily affected by the sampling noise, the high-order linear tracking differentiator (TD) is used to obtain the derivatives of the signal. Finally, a control platform based on STM32G474 is built. The experimental results show that compared with the traditional sliding mode controller, the improved second-order sliding mode controller has stronger robustness, better dynamic performance and higher practical application value.
HOU Yuanxiang,WU Qinghui,CAI Jianzhe. Design of fixed frequency Buck digital power based on second order sliding mode control[J]. Electrical Engineering, 2021, 22(5): 56-61.
2021, Vol. 22 
