New Synchronous Rectifier Control Scheme for High Efficiency and Density Interleaved Boost Converter With Passive Soft-Switching Cell

This paper proposes a new synchronous rectifier (SR) control for high efficiency and density interleaved boost converter with a passive soft-switching cell (IBC-PSC). In the interleaved converters, the soft-switching cells including active components have been proposed to reduce switching losses without an increase of conduction losses. However, these active components increase the weakness and cost of the converter. On the other hand, the proposed scheme restricts the increase of conduction losses by turning off the SRs when the circulating currents occur in IBC-PSC. Therefore, the proposed scheme not only reduces the additional conduction and circulating losses as the load decreases but also maintains zero-voltage switching (ZVS) conditions without additional active components. Furthermore, since the proposed scheme naturally reduces the input current ripples as the load decrease, the strict design condition of the boost inductors is relaxed and high-power density design can be achieved. The experimental results verify the effectiveness of the proposed scheme.