Predictive Branch Energy Controller for a Hybrid Modular Multilevel Converter in Quasi-Three-Level Operation

The hybrid modular multilevel converter was introduced in literature as an alternative topology for variable-frequency medium-voltage drives. The converter is designed to operate in a quasi-three-level operation mode. The focus of this paper is on a novel predictive branch energy controller which reduces the peak branch currents in comparison to the branch energy controller presented in the literature. This is experimentally validated by side-by-side measurements on a low-voltage prototype.