The effect of common-mode voltage elimination on the iron loss in machine core laminations of multilevel drives

This paper studies the effect of common-mode voltage elimination (CMVE) on the iron loss of electrical machine core laminations under multilevel converter supply. Three identical magnetic ring cores are excited by either a three-level T-type or five-level dual T-type voltage source converter to study the behavior of CMVE on a three-phase system. Both multilevel converters are controlled by using a space vector pulse width modulation as it is one of the most often used techniques for CMVE. In the three-level case study, the iron loss is increased by almost 5% when CMVE is implemented. These experimental results are verified numerically with a dynamic iron-loss model. Moreover, the effect of CMVE on a synchronous machine drive system is studied, in the full paper.