Modular Multilevel Converters: Key Features, Control Strategies and Main Challenges

Voltage source multilevel converters rank among the most popular solution to implement hvdc systems and efficiently integrate usually remote concentrated renewable energy sources. This chapter presents some of the converters that belong to this group. More specifically, a major emphasis is put on the modular multilevel converter (mmcs) by describing its topology, key features, pros and cons with respect to other converter technologies, as well as the reasons for its increasing popularity in the recent years. Lastly, after explaining a typical mmc control structure, the chapter highlights the challenges posed by mmcs from a simulation perspective. One of these challenges, namely the electromagnetic transient simulation, constitutes the main cornerstone of this book.