Power loss comparison in two- and three-level PWM converters

摘要

This paper presents a fair comparison of power losses in two-level and NPC three-level PWM converters using different switching devices. Conduction losses for IGBT and diode are calculated as a function of modulation index and power factor. Switching losses are calculated as a function of the switching frequency. Three-level converters give a lower total power loss compared with two-level converters. Cost comparison has shown the two-level configuration is about 25% cheaper than the three-level configuration.