Fundamental State-Space Modeling Methodology for the Flying Capacitor Multilevel Converter

Abstract

In recent decades the flying capacitor multilevel (FCML) converter has been demonstrated to be a highly com-pact and efficient substitute for conventional switched inductive topologies. However, the fundamental dynamical behavior of the additional flying capacitor voltages has still not been well charac-terized to a predictable level for even the simplest phase-shifted PWM modulation strategies. This work presents a computation-ally efficient analytical model and methodology for describing the fully generalized buck FCML topology with a state-space dynamical representation. The model is successfully validated against a high-performance five-level hardware prototype.