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.