Bifurcation Analysis under Various Modulation Techniques in PWM-Controlled DC-DC Converters

The type of carrier signal waveform plays a pivotal role in the dynamic response of the PWM-controlled DC-DC converters. To fully understand the nonlinear behavior of DC-DC converters, this paper aims to dissect the bifurcation process in a PWM-controlled buck converter under various modulations. To this end, various carrier signal waveforms, including single-edge modulation, symmetrical and asymmetrical dual-edge modulations, and various phase-shifted PWMs are considered. Next, using discrete-time modeling, the dynamic analysis of the system at various phase shifts is performed. Inspection of the bifurcation diagram and eigenvalue trajectories, obtained by shifting the gate signal within the switching period, reveals that the converter experiences period-1, period-2, and period-4 orbits within one switching period. The results of this analysis are validated through simulation studies and experiments.