Review on Multi-Level Voltage Source Converter Based HVDC Technologies for Grid Connection of Large Offshore Wind Farms

This paper focuses on reviewing grid connection of large offshore wind farms (OWFs) employing current state-of-the-art voltage source converter based high-voltage direct current (VSC-HVDC) technologies. A brief review of the VSC-HVDC evolvement is presented, followed by an overview of the advantages of employing VSC-HVDC for grid connection of large OWFs remotely located from the shore. A detailed description of the topologies is provided, and simulation results are presented in order to illustrate some of the main features of the most popular multi-level VSC-HVDC topology. Based on the review, it is found that there are currently three vendors of the VSC-HVDC. Furthermore, it is found that the VSC-HVDC is a promising technology for grid connection of remotely located OWFs and is going to be the preferred choice of remotely located OWF grid connection in e.g. the UK.