Theoretical Analysis and Experimental Validation of Flying-Capacitor Multilevel Converters Under Short-Circuit Fault Conditions

Addressing the increasing demand for high-efficiency and high-power-density converters, flying-capacitor multilevel converter has shown itself as a promising topology. A key advantage of this topology is reduced voltage rating switches, though also makes it vulnerable to device failure during short-circuit conditions. Despite large interest in fault-tolerant operation these alongside detailed descriptions balancing, little research focused on fault analysis, which may cause switch if not properly designed for. Therefore, article presents comprehensive model describing large-signal switching behavior general N-level converter. Highly simplified models used predict evolution current stress are proposed, targeted at practicing engineers conservative design guidelines. These determine critical time remedial action before reaching some predefined maximum 2-to-10-level fully configurable circuit hardware prototype experimentally perform different tests that show good match measured behavior.