A 600-W Four-Stage Phase-Shifted-Parallel DC-to-DC Converter

An unconventional switched mode power supply (SMPS) architecture, developed as four 150-W buck-boost or flyback-type switching stages operated in phase-shifted-parallel (PSP), is introduced. 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.