A 600 watt four stage phase-shifted-parallel DC-to-DC converter

This paper introduces an unconventional SMPS power stage architecture which is developed as four 150w buck-boost or flyback type switching stages which are operated in phase-shifted-parallel (PSP). The flybacks are operated in the continuous mode with intersecting conduction on both input and output sides; they are switched in cyclic sequence with one-fourth of a switching period following turn-on of one stage before turn-on of the next stage. PSP operation provides substantial improvements in intermediate power level SMPS for spacecraft applications.