Modeling and Bifurcation Analysis of Buck Converters Under Peak Current-Mode Control

The conventional averaging model is only suitable for low-scale bifurcation analysis, and the discrete-time model cannot be developed easily for some particular systems. In this paper, an improved averaging model is derived for peak-current-mode (PCM) controlled Buck converters in continuous-conduction mode (CCM). The improved average model retrieved the high frequency switching information from the conventional averaging model. It's suitable for researching the fast-scale bifurcation of PCM-controlled Buck converters with slope compensation. Due to the PCM-controlled Buck converter has sample-hold effect in the inner current loop. Then the sample-hold effect is added into the average model of PCM Buck converter, and obtained the more accurate improved averaging model. Bode diagrams and bifurcation diagrams are shown that the proposed modeling method is correct and effective.