Magnetics design and optimization for tapped-series-capacitor (TSC) power converters

Abstract

High voltage conversion ratio dc-dc converters are needed in a wide range of applications including power supplies for data centers and robotics. Hybrid switched-capacitor-magnetics power converters can leverage the advantages of capacitor-based circuits and inductor-based circuits to achieve high efficiency and high power density. This paper investigates the design method for an emerging family of hybrid switched-capacitor-magnetics circuits - tapped-series-capacitor (TSC) power converters - that can benefit high voltage conversion ratio applications. By resonating switched-capacitor circuits with coupled-magnetics and applying frequency modulation, zero-voltage-switching (ZVS) can be achieved across a wide input voltage range and load range. Coupled magnetics with low coupling coefficients are key elements in this family of power converters. Methodologies for designing high-frequency printed-circuit-board (PCB) magnetics with sophisticated winding patterns are also presented and experimentally verified.