Current Sharing and Phase Alignment for Independent Parallel Power Supplies

The trend in next-generation switched-mode power supplies will lead to modular, scalable solutions which can deliver power efficiently over a wide range of operation. Multiple parallel power stages, often called “phases”, are necessary to meet these requirements. This paper details a new approach to introduce more control features like phase-alignment, current sharing and phase shedding, which improve the efficiency of the overall dc-dc converter. An advantage of the proposed method is that it does not require communication signals between the individual controllers and is therefore fully scalable and cost effective. Experimental results for a FPGA prototype implementation are presented.