Linear generator-based wave energy converter model with experimental verification and three loading strategies

Yue Hong; Mikael Eriksson; Valeria Castellucci; Cecilia Boström; Rafael Waters

Linear generator-based wave energy converter model with experimental verification and three loading strategies

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Author(s): Yue Hong ¹ ; Mikael Eriksson ² ; Valeria Castellucci ¹ ; Cecilia Boström ¹ ; Rafael Waters ^{1, 2}
- Affiliations: 1: Division for Electricity, Uppsala University, SE-751 21 Uppsala, Sweden ;
  2: Department of Engineering Sciences, Seabased AB, SE-751 21 Uppsala, Sweden
Source: Volume 10, Issue 3, March 2016, p. 349 – 359
DOI: 10.1049/iet-rpg.2015.0117 , Print ISSN 1752-1416, Online ISSN 1752-1424

This is an open access article published by the IET under the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0/)

Received 20/03/2015, Accepted 08/09/2015, Revised 20/07/2015, Published 01/03/2016

Within the Lysekil wave energy research project at the Swedish west coast, more than ten Wave Energy Converters (WECs) prototypes have been developed and installed in an ocean based test site. Since 2006 various experiments have been conducted and the generated electricity was delivered to shore at a nearby island. While experiments are essential for the development of wave energy converters, theoretical studies and simulations are an important complement – not only in the search for advanced designs with higher efficiency, but also for improving the economic viability of the studied concepts. In this paper a WEC model is presented. The model consists of three subsystems: i) the hydrodynamic source, ii) the linear generator model, and iii) the electrical conversion system. After the validation with the experimental results at the research site, the generator model is connected to three passive load strategies – linear resistive load, passive rectification and resonance circuit. The paper focuses on analysing the operation of the model coupled with three load cases. The results prove that the WEC model correctly simulates the linear generator developed in the Lysekil Project. Moreover, the comparison among different load cases is made and discussed. The results gives an indication of the efficiency of energy production as well as the force ripples and resulting mechanical loads on the wave energy converters.

References

1. 1)
  - 11. Eriksson, M., Isberg, J., Leijon, M.: ‘Theory and experiment on an elastically moored cylindrical buoy’, IEEE J. Ocean. Eng., 2006, 31, (4), pp. 959–963 (doi: 10.1109/JOE.2006.880387).
2. 2)
  - 9. Castellucci, V., Abrahamsson, J., Svensson, O., et al: ‘Algorithm for the calculation of the translator position in permanent magnet linear generators’, J. Renew. Sustain. Energy, 2014, 6, p. 063102 (doi: 10.1063/1.4900553).
3. 3)
  - 15. Ekergård, B., Boström, C., Hagnestål, A., et al: ‘Experimental results from a linear wave power generator connected to a resonance circuit’, WIREs Energy Environ., 2013, 2, pp. 456–464 (doi: 10.1002/wene.19).
4. 4)
  - 12. Bostrom, C., Waters, R., Lejerskog, E., et al: ‘Study of a wave energy converter connected to a nonlinear load’, IEEE J. Ocean. Eng., 2009, 34, (2), pp. 123–127 (doi: 10.1109/JOE.2009.2015021).
5. 5)
  - 7. Eriksson, M., Waters, R., Svensson, O., et al: ‘Wave power absorption: experiments in open sea and simulation’, J. Appl. Phys., 2007, 102, p. 084910 (doi: 10.1063/1.2801002).
6. 6)
  - 5. Krishna, R., Svensson, O., Rahm, M., et al: ‘Analysis of linear wave power generator model with real sea experimental results’, IET Renew. Power Gener., 2013, 7, 5, pp. 574–581 (doi: 10.1049/iet-rpg.2012.0117).
7. 7)
  - 17. Boström, C., Leijon, M.: ‘Operation analysis of a wave energy converter under different load conditions’, IET Renew. Power Gener., 2015, 3, pp. 245–250.
8. 8)
  - 13. Malmstadt, H.V., , Enke, C.G., , Toren, E.C.: ‘Electronics for scientists’ (Physics Today, 1963).
9. 9)
  - 18. Boström, C., Lejerskog, E., Tyrberg, S., et al: ‘Experimental results from an offshore wave energy converter’, ASME. J. Offshore Mech. Arct. Eng, 2010, 132, (4), pp. 041103–041103-5 (doi: 10.1115/1.4001443).
10. 10)
  - 3. Hong, Y., Hultman, E., Castellucci, V., et al: ‘Status update of the wave energy research at Uppsala University’. Proc. 10th European Wave and Tidal Conf., Aalborg, Denmark, 2–5 September 2013.
11. 11)
  - 14. Boström, C.: ‘Electrical systems for wave energy conversion’. PhD thesis, Uppsala University, 2011.
12. 12)
  - 8. Waters, R., Rahm, M., Eriksson, M., et al: ‘Ocean wave energy absorption in response to wave frequency and amplitude – offshore experiments on a wave energy converter’, IET Renew. Power Gener., 2011, 5, (6), pp. 465–469 (doi: 10.1049/iet-rpg.2010.0124).
13. 13)
  - 1. Waters, R., Stålberg, M., Danielsson, O., et al: ‘Experimental results from sea trials of an offshore wave energy system’, Appl. Phys. Lett., 2007, 90, (3), p. 034105 (doi: 10.1063/1.2432168).
14. 14)
  - 16. Boström, C., Ekergård, B., Waters, R., et al: ‘Linear generator connected to a resonance-rectifier circuit’, IEEE J. Ocean. Eng., 2013, 38, (2), pp. 255–262 (doi: 10.1109/JOE.2012.2227552).
15. 15)
  - 6. Eriksson, M.: ‘Modelling and experimental verification of direct drive wave energy conversion’. PhD thesis, Uppsala University, 2007.
16. 16)
  - 10. Eriksson, M., Isberg, J., Leijon, M.: ‘Hydrodynamic modelling of a direct drive wave energy converter’, Int. J. Eng. Sci., 2005, 43, (17–18), pp. 1377–1387 (doi: 10.1016/j.ijengsci.2005.05.014).
17. 17)
  - 4. Ekström, R., Ekergård, B., Leijon, M.: ‘Electrical damping of linear generators for wave energy converters – a review’, Renew. Sustain. Energy Rev., 2015, 42, pp. 116–128 (doi: 10.1016/j.rser.2014.10.010).
18. 18)
  - 2. Waters, R.: ‘Energy from ocean waves: full scale experimental verification of a wave energy converter’. PhD thesis, Uppsala University, 2008.

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Linear generator-based wave energy converter model with experimental verification and three loading strategies

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