Reliability Investigation and Efficiency Analysis for a Family of High-Gain DC–DC Converters

Most conventional high-gain dc–dc converter topologies prioritize voltage gain enhancement. However, for practical applications such as photovoltaic and fuel-cell systems, improving converter efficiency rather than increasing voltage gain beyond a certain threshold is of paramount importance. This paper presents a comprehensive analysis of five newly developed high-gain dc–dc converters (HGDC) architectures. The introduced configurations substantially reduce current stress on both passive and active components, particularly those positioned near the input side, thereby improving overall efficiency. A detailed comparative study against published HGDCs is conducted. The results demonstrate that reduced current stress directly contributes to higher efficiency in the introduced Topologies-1 and -4, outperforming both the remaining introduced converters and conventional solutions. Furthermore, a small-signal model for Topologie-1 is developed, and the necessary transfer functions and frequency response are obtained with a Bode plot, and a PI controller is designed. Experimental validation for Topologie-1 and Topologie-4 demonstrates successful step-up of 48 V to 650 V at 0.5 kW and 50 kHz switching frequency. Finally, conducted the component-level reliability investigation to assess the failure rate of components.