A new current-fed, isolated PWM DC-DC converter

This paper introduces a new current-fed DC-DC power converter circuit whose features are as follows: (1) two active switches gated in a complementary and asymmetrical way, connected to the same ground; (2) inherent high reliability provided by the input boost inductor; (3) isolation by a high-frequency transformer; and (4) purely capacitive output filter. Circuit operation, theoretical analysis, and design procedure are presented. Experimental results taken from a prototype, rated at 48 V/300 W, are also included in the paper to demonstrate the validity of the theoretical analysis.