Demystifying Capacitor Voltages and Inductor Currents in Hybrid Converters

Abstract

This paper presents a modeling method to accurately predict DC and ripple values of flying capacitor voltages and inductor currents in hybrid converters by recognizing a key relationship between median and average values of these state variables. The method is demonstrated for the Dual-Phase Multi-Inductor Hybrid (DP-MIH) converter and 3-Level Buck converter. Analytical details and intuitive explanations are presented for the well-known balancing problem of flying capacitor voltages and inductor current fluctuations in hybrid converters. Simulation results for the converters at different operating conditions are provided to verify the method and analytical results.