AIMS Energy, 2014, 2(4): 385-398. doi: 10.3934/energy.2014.4.385.

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Adapting AC Lines to DC Grids for Large-Scale Renewable Power Transmission

Department of Electrical Engineering, University of the Basque Country - UPV/EHU, Alameda de Urquijo, s/n-Bilbao, 48013, Spain

All over the world, governments of different countries are nowadays promoting the use of clean energies in order to achieve sustainable energy systems. In this scenario, since the installed capacity is continuously increasing, renewable sources can play an important role. Notwithstanding that, some important problems may appear when connecting these sources to the grid, being the overload of distribution lines one of the most relevant. In fact, renewable generation is usually connected to the nearest AC grid, although this HV system may not have been designed considering distributed generation. In the particular case of large wind farms, the electrical grid has to transmit all the power generated by wind energy and, as a consequence, the AC system may get overloaded. It is therefore necessary to determine the impact of wind power transmission so that appropriate measures can be taken. Not only are these measures influenced by the amount of power transmitted, but also by the quality of the transmitted power, due to the output voltage fluctuation caused by the highly variable nature of wind. When designing a power grid, although AC systems are usually the most economical solution because of its highly proven technology, HVDC may arise in some cases (e.g. offshore wind farms) as an interesting alternative, offering some added values such as lower losses and better controllability. This way, HVDC technology can solve most of the aforementioned problems and has a good potential for future use. Additionally, the fast development of power electronics based on new and powerful semiconductor devices allow the spread of innovative technologies, such as VSC-HVDC, which can be applied to create DC grids. This paper focuses on the main aspects involved in adapting the existing overhead AC lines to DC grids, with the objective of improving the transmission of distributed renewable energy to the centers of consumption.
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Keywords renewable energy integration; distribution lines; power upgrade; VSC-HVDC; DC grid

Citation: D. Marene Larruskain, Inmaculada Zamora, Oihane Abarrategui, Garikoitz Buigues, Víctor Valverde, Araitz Iturregi. Adapting AC Lines to DC Grids for Large-Scale Renewable Power Transmission. AIMS Energy, 2014, 2(4): 385-398. doi: 10.3934/energy.2014.4.385


  • 1. IEA (2012) Energy outlook 2012. Executive summary. Technical Report.
  • 2. BP (2013) Energy Outlook 2030. Technical Report.
  • 3. Desertec (2009) Clean Power from Deserts. Whitebook. Available from:
  • 4. Medgrid (2013) Towards an Interconnected Mediterranean Grid: Institutional Framework and Regulatory Perspectives. Available from:
  • 5. De Decker J, et al. (2011) Offshore Electricity Grid Infrastructure in Europe. OffshoreGrid, Techical Report.
  • 6. Hammon TJ (2006) Integrating renewable energy sources into European grids. Proceedings of the 41st International Universities Power Engineering Conf. Newcastle upon Tyne.
  • 7. Weimers L (2011) A European DC Super Grid. Available from:
  • 8. Flourentzou N, Agelidis VG, Demetriades GD (2009) VSC-based HVDC Power transmission systems: an overview. IEEE T Power Electr 24(3): 592-602.
  • 9. Van Hertem D, Ghandhari M (2010) Multi-terminal VSC HVDC for the european supergrid: Obstacles. Renew Sust Energ Rev 14(9): 3156-3163.
  • 10. Ahmed N, Haider A, Van Hertem D, et al. (2011) Prospects and Challenges of Future HVDC SuperGrids with Modular Multilevel Converters. Proceedings of Power Electronics and Applications (EPE), Birmingham, UK.
  • 11. Dorn J, Huang H, Retzmann D (2007) Novel voltage-sourced converters for HVDC and FACTS applications. Cigré Symposium, Osaka, Japan.
  • 12. Xie H, Angquist L, Nee HP (2010) Design Study of a Converter Interface Interconnecting an Energy Storage with the dc-link of a VSC. IEEE Innovative Smart Grid Technologies Conference Europe, Gothenburg.
  • 13. Larruskain DM, Zamora I, Mazón AJ, et al. (2005) Transmission and distribution networks: AC versus DC. 9 Conference Hisp-Luso of Electr Ing, Marbella, Spain.
  • 14. Larruskain DM, Zamora I, Abarrategui O, et al. (2011) Conversion of AC distribution lines into DC lines to upgrade transmission capacity. Electr Pow Syst Res 81(7): 1341-1348.
  • 15. Clerici A, Paris L, Danfors P (1991) HVDC conversion of HVAC lines to provide substantial power upgrading. IEEE T Power Deliver 6(1): 324-333.
  • 16. Naidoo P, Estment RD, Muftic D, et al. (2005) Progress report on the investigations into the recycling of existing HVAC power transmission circuits fot higher power transfers using HVDC technology. IEEE PES Africa conf, Durban, South Africa.
  • 17. Rahman H, Khan BH (2007) Power upgrading of transmission line by combining AC-DC transmission. IEEE T Power Syst 22(1): 459-466.
  • 18. Muftic D (2008) HVDC transmission and converting AC to DC. Joint seminar on energy effic.
  • 19. Colla L, Rebolini M, Malgarotti S, et al. (2010) Analysis on the possible conversion of overhead lines from AC to DC. CIGRE 2010, Paris.
  • 20. Khan MI, Agrawal RC (2005) Conversion of AC line into HVDC. IEEE PES Africa conf, Durban, South Africa.
  • 21. Barthold LO, Clark HK, Woodford D (2006) Principles and applications of current modulated HVDC transmission systems. IEEE PES transm and distrib conf, Dallas, USA.
  • 22. Edris A (2006) EPRI power electronics-based transmission controllers reference book. The Gold Book, Tech. Rep. 1012414, California, USA.
  • 23. Edris AA, Barthold LO, Douglas DA, et al. (2008) Upgrading AC transmission to DC for maximum power transfer capacity. 12th Int Middle-East Power system conf, Aswan, Egypt.
  • 24. Larruskain DM, Zamora I, Abarrategui O, et al. (2014) VSC-HVDC configurations for converting AC distribution lines into DC lines. Electr Pow Energ Syst 54: 589-597.    
  • 25. IEC 61325 Regulation (1995) Insulators for overhead lines with a nominal voltage above 1000 V.
  • 26. Arrillaga J (1983) High voltage direct current Transmission, Peter peregrines, London.
  • 27. Franck CM (2011) HVDC Circuit Breakers: A Review Identifying Future Research Needs. IEEE T Power Deliver 26 (2): 998-1007.
  • 28. EN 50.341-1 Regulation (2001) Overhead electrical lines exceeding AC 45 kV.EN 50.423-1
  • 29. Regulation (2005) Overhead electrical lines exceeding AC 1 kV up to and including AC 45 kV.


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