DC-DC变换器滑模变结构控制研究

为提高DC-DC变换器的抗扰性能,研究了Boost变换器的滑模控制策略。本文首先利用状态空间平均法对Boost变换器进行数学建模,然后建立PID型滑模控制器,进而推导出系统等效控制表达式。为了得到更好的抗扰效果,用光滑函数代替符号函数,得到了去抖振控制表达式。最后利用Matlab/Simulink对两种控制方式进行仿真。仿真结果表明,采用本文控制方法的系统与采用PID型滑模控制相比,动态响应调节特性和稳态误差调节特性更好、鲁棒性更强。

Research on Sliding-mode Variable-structure Control of DC-DC Converter

To improve the anti-disturbance performance of a DC-DC converter,a sliding-mode control strategy for a Boost converter is studied in this paper.First,the state-space averaging method is used to model the Boost converter mathematically.Then,a PID-type sliding-mode controller is established,and the expression of system equivalent con?trol is derived accordingly.To realize a better anti-disturbance effect,a smoothing function is used instead of a symbolic function,thereby obtaining a control expression to reduce chattering.Finally,Matlab/Simulink is used to simulate the two control methods,and simulation results show that compared with the PID-type sliding-mode control,the system with the proposed control method has better dynamic response and steady-state error regulation characteristics,as well as stronger robustness.