Simple symmetric switched inductor high step-down converter

The voltage gain of a traditional buck converter is finite due to the high voltage across the semiconductor and reduced efficiency. A non-isolated high step-down DC–DC converter based on symmetric switched inductors is proposed in this paper. The connection of inductors in series or in parallel is controlled by switches to improve the conversion ratio. The converter has many beneficial characteristics, such as high step-down, reduced voltage stresses, and high efficiency. Moreover, it can realize voltage balance on the switches. The voltage on the switch does not oscillate and the loss of the switches is reduced. Therefore, the efficiency of the whole topology is improved. This paper discusses the operation principle, modes analysis, voltage gain analysis, voltage stress analysis, output ripple analysis, loss analysis, comparative analysis and design considerations. The correctness of the theoretical analysis of the proposed converter is verified by a laboratory prototype, and its peak efficiency reaches 96.5%.