Power Estimation and Optimum Design of a Buoy for the Resonant Type Wave Energy Converter Using Approximation Scheme

근사기법을 활용한 공진형 파력발전 부이의 발전량 추정 및 최적설계

Koh, Hyeok-Jun;Ruy, Won-Sun;Cho, Il-Hyoung

  • Received : 2012.11.19
  • Accepted : 2013.02.14
  • Published : 2013.02.28


This paper deals with the resonant type of a WEC (wave energy converter) and the determination method of its geometric parameters which were obtained to construct the robust and optimal structure, respectively. In detail, the optimization problem is formulated with the constraints composed of the response surfaces which stand for the resonance period(heave, pitch) and the meta center height of the buoy. Use of a signal-to-noise ratio calculated from normalized multi-objective results with the weight factor can help to select the robust design level. In order to get the sample data set, the motion responses of the power buoy were analyzed using the BEM (boundary element method)-based commercial code. Also, the optimization result is compared with a robust design for a feasibility study. Finally, the power efficiency of the WEC with the optimum design variables is estimated as the captured wave ratio resulting from absorbed power which mainly related to PTO (power take off) damping. It could be said that the resultant of the WEC design is the economical optimal design which satisfy the given constraints.


Resonance;Wave energy converter;Power buoy;Boundary element method;Response surface;Power take off;Captured wave ratio


  1. ANSYS, 2010. ANSYS AQWA Reference Manual. ANSYS Inc.
  2. Birk, L., Clauss, G.F., Lee, J.Y., 2004. Practical Application of Global Optimization to the Design of Offshore Structures. In Proc. of 23rd Int. Conf. on Offshore Mechanics and Arctic Engineering (OMAE'04), Vancouver, Canada, 567- 579.
  3. Colby, M., Nasroullahi E., Tumer K., 2011. Optimizing Ballast Design of Wave Energy Converters Using Evolutionary Algorithms. In GECCO'11, 1739-1746.
  4. Hagerman, G., Bedard, R., 2003. Guidelines for Preliminary Estimation of Power Production by Offshore Wave Energy Conversion Devices. EPRI Rpt. 297213.
  5. Kim, Y.D., Hong, K.Y., Shin, S.H., Ryu, H.J. Kim, S.H. Park, J.Y., 2011. A Technical Trend Analysis on Wave Energy Converting Technology. Journal of Ships & Ocean Engineering, 51, 73-80.
  6. Koh, H.J., Kim, J.R., Cho, I.H. Ruy, W.S., 2012. Optimum Design of a Buoy for the Resonant Type Wave Energy Converter Using Approximation Scheme. Proceedings of KSOE Fall Conference 2012, Busan, 117-120.
  7. Kweon, H.M., Kweon, O.K., Kang, J.H., Lee, J.R., Park, S.S., Cho, I.H., 2010. Wave-Energy-Farm Utilizing by Resonance Power Buoy. Research Proposal, KETEP.
  8. Park, S.H., 2009. Design of Experiments. Minyoungsa, Seoul, Korea
  9. Phadke, M.S., 1989. Quality Engineering Using Robust Design. Prentice-Hall, Englewood Cliffs, New Jersey.
  10. SolidWorks, 2001. SolidWorks Mamual. SolidWorks Co.
  11. Song, M.Sl, Kim, D.Y., Kim, M., Hong, K.Y., Jun, K.C., 2004. Analysis of Wave Energy Density for Korean Coastal Sea Area Based on Long-Term Simulated Wave Data. Journal of the Korean Society for Marine Enviromental Engineering, 7(3), 152-157.
  12. Roux, W.J., Stander, N., Hatfka, R.T., 1998. Response Surface Approximations for Structural Optimization. Int. J. Nume. Methods Eng., 42, 517-534.<517::AID-NME370>3.0.CO;2-L


Supported by : 한국에너지기술평가원(KETEP), 지식경제부