Passive Component Modeling and Optimal Size Allocation for Hybrid-Resonant Switched Capacitor DC-DC Converters

This paper explores methods to optimize hybrid-resonant switched capacitor (ReSC) DC-DC converters. A technique is presented that leads to optimal size allocation between flying capacitors and inductor with a constraint on total size of passives. Both the losses in the active semiconductor devices and in the magnetic component are modeled. For coreless inductors, the low-frequency DC losses and the high-frequency AC (skin effect) losses are treated separately. For cored inductors, the Improved Generalized Steinmetz Equation (iGSE) is used to model the core losses, and a design algorithm and example are presented. It is shown that for optimal operation, flying capacitors and inductor should be allocated roughly similar size.