Transformer-Less High Step-Down Converters with Reduced Device Count: Review

Transformer-less DC-DC converters are crucial in various applications, especially when a high step-down voltage transformation is required. This paper comprehensively reviews the transformer-less DC-DC converters, focusing specifically on the reduction in the number of inductors, capacitors, and switches. This paper provides the limitations of conventional buck converters. An in-depth analysis explores each topology's converter structure, advantages, and limitations concerning high step-down requirements. Moreover, the review delves into the recent advancements and emerging trends in transformer-less DC-DC converter designs modified for high step-down applications. Special attention is paid to efficiency considerations, size constraints, total number of components, and stresses on switches, and the comparative analysis is presented in this paper. This review intends to help people make better decisions and inspire new ideas in power electronics, specifically focusing on high step-down voltage conversions.