Ultra-Wide Output Voltage Range DC Power Supply with Multiple Power Modules Series/Parallel Variable Structure and Automatic Voltage/Current Sharing

An ultra-wide output voltage range dc power supply composed of multiple power modules and output variable structure circuits (OVSCs) is studied in this paper. Each OVSC is composed of one active switch and two diodes, and by turn-on/-off these active switches, outputs of these power modules can either be in-parallel or in-series. Consequently, the total output voltage range is extended significantly while the peak voltage and current stresses of each module is not increased, which is helpful to design the modules and improve the efficiency over the whole output range. Furthermore, an optimized isolated buck-boost (IBB) converter is employed to construct the power supply and automatic voltage/current sharing can be realized between different modules only by single output voltage loop. Operational principles and control strategy are analyzed in detail. Experimental results are provided to verify the effectiveness and advantages of the power supply.