电流模式控制Buck-Boost变换器建模及非线性现象仿真

根据电流模式控制下Buck-Boost变换器的工作特性,建立变换器的统一数学模型,并基于Matlab/Simulink 仿真软件,分别搭建工作于电流连续和电流断续模式下变换器的仿真模型.通过对电流连续模型进行仿真,揭示参考电流Iref和电感L在不同的工作情况下出现倍周期分叉并最终导致混沌的现象；对电流断续模型进行仿真,得出以输入电压E变化时的混沌相图,验证电流断续模式下混沌现象的存在性.同时为消除这2种模式下的混沌现象,引入PID控制器.仿真结果表明:通过设置适当的参数,可以有效地抑制变换器中的混沌现象.

Modeling and nonlinear phenomena simulation of current-mode controlled Buck-Boost converter

According to the working characteristics of current-mode controlled Buck-Boost converter,the uniform mathematic model of converter was set up,two simulation models of converter worked in continuous conduction mode(CCM) and discontinuous conduction mode(DCM) was built by employing Matlab/Simulink soft.The simulation results were gained by using the two kinds of models.In the CCM model,the phenomenon of bifurcation and chaos were obtained with resistance L and reference current Iref varying;in DCM model,the phase diagrams were obtained by changing input voltage E,which proved the existence of chaotic phenomena.A PID controller was applied to eliminate the chaos phenomena in two models.All simulation results demonstrate that the chaos phenomena can be restrained by choosing appropriate parameters of PID controller.