The Multiple-Output DC-DC Converter With Shared ZCS Lagging Leg

A multiple-output dc-dc converter with shared zero-current-switching (ZCS) lagging leg is presented in this paper. In this proposed converter, each output is regulated by the phase shifted between the independent leading legs and the shared lagging leg. The switches in the leading legs process the individual output power and work in zero-voltage switching (ZVS), which are suitable for utilizing the MOSFETs; the switches in the shared lagging leg process the total output power and work in ZCS, which especially suit for using the insulated gate bipolar transistor. The ZVS of the leading legs is easy to achieve and the ZCS of the lagging leg is independent of the loads. Therefore, the proposed converter has compact structure, fully regulation abilities, adapted soft-switching modes, and simple modulation schemes. Moreover, the new outputs can be conveniently obtained by using the uniform algorithm. In this paper, the derivation of the proposed converter is presented; the proposed shared ZCS lagging leg converter with dual output is analyzed, and the analysis is further extended to the general multiple-output situation; the state variation of the proposed converter is also surveyed; finally, a three-output prototype with 200-240 V input, 24 V/5 A, 15 V/15 A, and 12 V/10 A outputs is built, and the analysis is verified by the experimental results.