A Comparison between Different Models of the Modular Multilevel Converter

In this article, we compare the detailed switching (DS) model of the modular multilevel converter (MMC) with the arm average model (AA), the state-space time-invariant (SSTI) model, and the harmonic state-space (HSS) model. We consider a five sub-modules (SM) and a 50 SM application. We evaluate their performance in terms of accuracy on the representation of dynamics and simulation speed. The results show that the AA can be 700 times faster than the DS model, while the SSTI and the HSS can be more than 7000 times faster than the DS model. The highest relative deviation between models is kept under 8%.