Multilevel converters are power electronics topologies that can generate two or more voltage levels in each output phase. As a result, the voltage and current waveforms generated have lower total harmonic distortion. There are different configurations of multilevel converters, which consist on connecting power device or converters in series. Consequently, high voltage can be handled on the dc and ac side of the converter, while each device stands only a fraction of the total dc-link voltage. For these reason multilevel converters are generally used for high-power applications. Modular multilevel converter (MMC) is a recent topology for power conversion. During the last years, its popularity has increased due to its characteristics of modularity, availability and controllability. This topology is having a great relevance in the industry. MMC has a lot of advantages, especially for high voltage direct current lines (HVDC). The main objective is to study its operation and the main modulation techniques. It also has been made the study and design of a sub-module of this converter. The study and design of a sub-module of this topology has been done and designed with silicon carbide (SiC) MOSFETs transistors. This transistor can handle higher temperatures and has lower switching losses