A high step-up, non-isolated DC-DC converter with reduced repeated power processing

This paper proposes a non-isolated converter that is based on a flyback topology. The proposed converter has high conversion ratio and achieves higher efficiency with reduced voltage and current stresses on the power semiconductors when compared to the conventional flyback converter. Analysis and key converter operating waveforms are reported in the paper. Experimental results taken from a 60 W laboratory prototype with 24 V input voltage delivering 200 V to the load are presented to confirm the capability of the converter to generate high-voltage ratios. The converter maintains efficiency of over 90 % from light-load to nominal-load conditions. The proposed converter is suitable for applications such as DC micro-grids and solar electrical energy systems which require high step-up DC-DC converters but may not necessarily require transformer isolation.