A new high step-down soft-switched DC-DC converter based on coupled inductor

This study introduces a new non-isolated DC-DC converter capable of achieving a high step-down conversion ratio. The design reduces switching losses through soft-switching, allowing switches to operate under Zero Voltage Switching (ZVS), which enhances efficiency. The converter employs a single coupled inductor without additional inductors in the power path, achieving low voltage gain and an extended duty cycle, resulting in reduced losses, lower costs, and optimal efficiency compared to similar topologies. Voltage stress on semiconductors is minimised by recycling leakage inductance energy to the output. The proposed converter achieves a greater step-down voltage gain per component compared to similar designs. Different operational modes and design aspects are examined. A prototype was constructed, and experimental results confirmed the theoretical analysis.