A High Step-down Dual Output Non-Isolated DC/DC Converter

This paper presents a DC/DC buck-boost converter topology with high voltage gain and dual outputs. Unlike many of the high step-down/step-up DC/DC converters, this topology uses relatively less number of LC components and three active semiconductor devices, switched in a non-overlapping way. In the proposed converter, the overall gains at both the output ports are non-linear functions of duty-cycles of the power devices, which help achieve an overall step-down/step-up gain of 10 to 15. An experimental prototype, converting 48V DC to +/- 5V DC at 100W output power is developed, in order to verify the operation and effectiveness of the proposed converter structure. An output voltage ripple of +/- 1% and a conversion efficiency of 94% are achieved according to the experimental results.