A novel high step-up zero-current-switching tapped-inductor boost converter

As global warming due to burning fossil fuels and natural resource depletion issues have emerged, the development of renewable energy sources such as photovoltaics (PV) has been brought to recent interest. Amongst the vast efforts to harvest and convert solar energy into electricity, module integrated converters (MIC) have become a worthy topic of research for small sized grid connected photovoltaic systems. Due to the required high boosting qualities, only a restricted amount of DC/DC converter topologies can be applied to MICs. This paper investigates the possibility of a tapped-inductor boost converter as a candidate for PV MICs. A novel tapped inductor boost converter with zero current switching (ZCS) is proposed. By deploying an auxiliary switch and an additional capacitor, the inductor current can be resonantly shaped to achieve ZCS. This results in reduced switching losses and enhanced overall efficiency. Also, the zero crossing point of the inductor current can easily be detected, which can help digitalize the converter controller. The operation and performance of the proposed converter is verified by a 200 W prototype converter.