Current-resonant DC-DC converter designed to achieve 95% of total efficiency in power conditioner for fuel cell

This paper describes a DC-DC converter which offer the efficiency of 98% for the 800W fuel-cell system (FC). The authors are currently developing the power conditioner for the FC system the efficiency of which is higher than 95%. To get the efficiency, the efficiency of the DC-DC converter has to exceed 97%. To reduce switching losses, the proposed DC-DC converter consists of three identical conversion circuits including a current resonant circuit and a synchronous rectification circuit respectively, and their inputs are connected in parallel and their outputs connected in series. The experimental results show that the proposed converter attains to the target efficiency.