Nonlinear phenomenon in a current-mode controlled buck-boost converter with solar cell input via varying reference current

This paper investigates the nonlinear phenomena in a current-mode controlled buck-boost DC-DC converter with solar cells. The converter is operated in continuous conduction mode (CCM) with inductor current. It is also controlled by varying reference current to study the occurrence of nonlinear phenomena from the initial periodic steady-state to period-doubling bifurcation into the last chaos condition. Firstly, this paper introduces the basic principles of solar cells and current-mode controlled buck-boost converter. Secondly, the equivalent circuit model of solar cells and converter is constructed and the mathematical model is derived. Then, this study adopts MATLAB / SIMULINK for modeling and simulation. The converter nonlinear phenomena are verified through time-domain waveforms, phase portraits and bifurcation diagrams.