混杂系统DC/DC变换器的自适应滑模控制

Adaptive Sliding Mode Control of Hybrid DC/DC Converter

DC/DC变换器在工作时,输入电压或负载因外界不确定因素的影响,将导致系统出现运行工作不稳定等情况。在此采用混杂系统理论构建DC/DC变换器的观测器模型,设计自适应律观测输入电压和负载的变化,结合滑模控制响应速度快的优点,提出一种新颖的自适应滑模控制(ASMC)方法。通过Lyapunov函数证明得出输入电压以及负载变化的自适应方程并将其应用于滑模控制,利用滑模等效控制恒定开关频率,同时采用一种新型指数趋近律,相比传统指数趋近律具有更快的收敛速度。最后,搭建仿真实验平台,通过与传统比例积分(PI)算法进行比较,验证所提自适应滑模控制算法的可行性。

The input voltage or load is affected by external uncertain factors when the DC/DC converters are working.It may lead to unstable system operation.The DC/DC converter observer model is constructed by the hybrid system theory.A novel method of adaptive sliding mode control(ASMC)is also presented.The adaptive equation of input voltage and load change is proved by Lyapunov function and applied to sliding mode control.The sliding mode equivalent control is employed to constant switching frequency.Moreover,a new type of exponential reaching law is adopted.Comparing to traditional exponential reaching law,it has faster convergence speed.Finally,the simulation and experimental platforms are built to make a contrast with traditional proportion-integration(PI)algorithm.The feasibility of the ASMC algo-rithm is verified effectively.