Comparison of soft-switching voltage-fed and current-fed bi-directional isolated Dc/Dc converters for fuel cell vehicles

This paper presents a comparison of two potential soft-switching bi-directional high-frequency transformer isolated voltage-fed and current-fed dc/dc converters for fuel cell vehicle application. The given comparison and discussion is suitable for a front-end dc/dc converter for a fuel cell inverter. The circulating and peak currents, components´ ratings, size, losses, and efficiency are compared. Current-fed converter has been justified due to its merits over voltage-fed converter for the given applications. Experimental results of the current-fed converter have been illustrated. Switching losses are reduced a lot due to soft-switching of primary and secondary devices and higher efficiency. It allows high switching frequency operation, which results in compact and low cost system.