In this paper, a soft switching buck dc/dc converter applicable for fuel cell has been analyzed and the complete details of designing have been presented. Reduction in switching losses and the elimination of voltage/current stresses of the switches are the major advantages of the aforementioned converter. In this converter, the switches are to be ON under zero voltage and zero current conditions, whereas they are to be OFF under zero voltage condition. This converter can be used in high switching frequency. In this paper, the principles of the performance, full details of the analyses of conduction modes, and designing approach have been presented. The performance and correct operation of the converter are validated by the experimental and simulation in PSCAD/EMTDC software.

In this paper, a non-isolated three-port zero voltage switching bidirectional dc-dc converter without input current ripple. Some advantages of proposed converter are zero voltage switching of main switches, zero current switching of auxiliary switches. By using two active snubbers, it is possible to reduce circulating current and conduction losses. Free ripple condition of input currents is obtained by using coupled inductors in any stages that it reduces size of converter. The proposed converter can be used in boost, buck and buck-boost operation mods. If all of low voltage sources are equal or less than high voltage source, it is possible to increase the number of input sources to as a kind of -port converter. Finally, the zero voltage and zero current switching of switches and ripple free input currents of the proposed dc-dc converter is verified thruogh the simulation results in PSCAD/EMTDC software.