Non-Smooth Bifurcation Analysis of Multi-Structure Multi-Operating-Mode Power Electronics Systems for Applications With Renewable Energy Sources

The stand-alone hybrid renewable power generation systems for local applications have gained popularity in recent years. However, due to the intermittent nature of the renewable resources, the hybrid renewable power generation systems are often designed to operate with multi-structure and multi-operating-mode. As a result, a non-smooth bifurcation may occur as the system switches its operating mode. This brief aims to study this kind of bifurcation. A formulation for multi-structure and multi-operating-mode system is described and a systematic procedure for analyzing the non-smooth bifurcation is given. A stand-alone photovoltaic-battery hybrid power system is taken as an example for illustrating the possible non-smooth bifurcation, which is further identified and analyzed with a discrete-time mapping model. Moreover, extensive circuit simulations and experiments verify the theoretical analysis.