Parallel-connected multilevel converter based multi-modular system with fundamental frequency SPWM

In this paper, two parallel-connected multilevel flying capacitor converter systems with the FF-SPWM control method are studied. Low switching losses, high power output and low THD of output are desired specifications for systems, A multi-modular systems based on flying capacitor multilevel converters can achieve the above three aims with the fundamental frequency SPWM control scheme with no phase-shifting among modules plus a specifically designed controller. They can also result in lower switching losses than those of single-module multilevel converters with the higher frequency PWM or higher frequency PWM two-level converters.