Modeling and Comparison of Passive Component Volume of Hybrid Resonant Switched-Capacitor Converters

Hybrid and resonant switched-capacitor (ReSC) converters enable efficient utilization of both active and passive components, and have the potential to achieve higher efficiency and higher power density than conventional SC and magnetic-based converters. One or more added inductors offer an additional degree of freedom in the design space, and it is of great interest to understand the trade-offs between capacitor and inductor allocation, for different circuit topologies. In this work, we present a method to analyze and optimize the total passive component volume from the energy/power transfer perspective. It is shown that the passive volume can be expressed and optimized as a function of flying capacitor voltage ripple, and no detailed operating conditions (e.g., P
_out
, f
_sw
, L and C values) are needed. Moreover, a normalized passive volume parameter is proposed for simple and fair topology comparison. Along with the normalized switch stress parameter (based on switch VA ratings), a framework to showcase the relative performance of ReSC topologies is created. The metrics proposed in this work can be used to visualize and compare the passive and active component utilizations among different topologies.