Discrete Iterative Map Model-Based Stability Analysis of Capacitor Current Ripple-Controlled SIDO CCM Buck Converter

Abstract

Capacitor current ripple (CCR) control is applied to single-inductor dual-output (SIDO) buck converter due to its advantages in reducing cross regulation and fast transient response. However, it shows that the stability of CCR-controlled SIDO CCM buck converter can be affected by circuit parameters. In this article, a 5-D discrete iterative map model of CCR-controlled SIDO CCM buck converter is established based on Poincaré maps. The bifurcation analysis and eigenvalues loci clearly shows that the effect of control parameters and load parameters on the stability of CCR-controlled SIDO CCM buck converter. Besides, the effect of studied circuit parameters on the stability range of the converter is investigated. Furthermore, the stability boundaries and stable regions of load parameters and control parameters are obtained by using eigenvalues analysis. The study results show that the increasing of proportional parameters would cause instability and it will reduce the stable region of load parameters. The converter has a stable region for load parameters and these two load parameters have influence on each other. Finally, experimental results are presented to verify the theoretical analysis in this article.