Operation of DC series connected offshore wind farm by using tap changing transformer with MMC-HVDC

In order to overcome economic disadvantage of offshore wind farm, many kind of grid connection and operation methods have been researched and analyzed by authors from around the world. The DC series connection of offshore wind farm is a solution to reduce installation and management costs, because this topology doesn't require installation of offshore platform which play a role as substation or high voltage direct current transmission system(HVDC) converter station. However, the DC link voltage of DC series wind farm may not be constant in accordance with variable wind speed. And only one wind turbine must be able to generate high DC link voltage for stable power transmission. Therefore, this paper proposes the operation of DC series connected wind farm by using tap changing transformer with modular multilevel converter(MMC)-HVDC.

[1]  Tore Undeland,et al.  Multilevel converters for a 10 MW, 100 kV transformer-less offshore wind generator system , 2013, 2013 15th European Conference on Power Electronics and Applications (EPE).

[2]  Ratna Dahiya,et al.  An approach to reduce the fluctuation of HVDC link current in series connected wind turbines , 2015, 2015 International Conference on Energy, Power and Environment: Towards Sustainable Growth (ICEPE).

[3]  Dong-Choon Lee,et al.  A Series-Connected Topology of a Diode Rectifier and a Voltage-Source Converter for an HVDC Transmission System , 2014, IEEE Transactions on Power Electronics.

[4]  Christophe Saudemont,et al.  Control strategies of a dc based offshore wind farm with series connected collection grid , 2016, 2016 IEEE International Energy Conference (ENERGYCON).

[5]  Jaewoo Kim,et al.  Converter control of PMSG wind turbine system for inertia-free stand-alone microgrid , 2016, 2016 IEEE Industry Applications Society Annual Meeting.

[6]  Gregory F. Reed,et al.  Comparison of HVAC and HVDC solutions for offshore wind farms with a procedure for system economic evaluation , 2013, 2013 IEEE Energytech.

[7]  Marco Liserre,et al.  Overview of Multi-MW Wind Turbines and Wind Parks , 2011, IEEE Transactions on Industrial Electronics.

[8]  Peter W. Lehn,et al.  Interconnection of Direct-Drive Wind Turbines Using a Series-Connected DC Grid , 2014, IEEE Transactions on Sustainable Energy.

[9]  Rainer Marquardt,et al.  An innovative modular multilevel converter topology suitable for a wide power range , 2003, 2003 IEEE Bologna Power Tech Conference Proceedings,.