Modern HVDC PLUS application of VSC in Modular Multilevel Converter topology

This paper presents an actual view into the development of High Voltage Direct Current (HVDC) converter stations build in Modular Multilevel Converter (MMC) topology. Explanations are given how voltage sourced converters (VSC) of large active power transmission capacity and independent controlled reactive power exchange capability are designed for terminals of HVDC Links. This modern type of self-commutated converters has been developed under brand name HVDC PLUS by Siemens for use in electric power systems.