Design considerations for a voltage-boosting DC-AC Modular Multilevel Converter

Abstract

The Modular Multilevel Converter (M2C) is a relatively recent addition to the family of multilevel power converters. This paper describes the topology, dynamic phasor modeling, and operation of a voltage boosting DC-AC Modular Multilevel Converter. A "Semi-Full Bridge" submodule with only two controlled semiconductors and immune to shoot-through faults suitable for such applications is presented. An inherently scalable averaged model using dynamic phasors is also presented, with a control methodology to reduce losses and attenuate unwanted current harmonics in the arms and capacitors. Verification of the model is provided with simulations and an experimental prototype power converter.