Ocean Systems Engineering

Techno-Press (테크노프레스)
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Wave energy converter by using relative heave motion between buoy and inner dynamic system

  • Cho, I.H. (Department of Ocean System Engineering, Jeju National University) ;
  • Kim, M.H. (Department of Civil Engineering, Texas A&M University) ;
  • Kweon, H.M. (Department of Civil Engineering, Kyongju University)
  • Received : 2012.12.03
  • Accepted : 2012.12.14
  • Published : 2012.12.25
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Abstract

Power-take-off through inner dynamic system inside a floating buoy is suggested. The power take-off system is characterized by mass, stiffness, and damping and generates power through the relative heave motion between the buoy and inner mass (magnet or amateur). A systematic hydrodynamic theory is developed for the suggested WEC and the developed theory is illustrated by a case study. A vertical truncated cylinder is selected as a buoy and the optimal condition of the inner dynamic system for maximum PTO (power take off) through double resonance for the given wave condition is systematically investigated. Through the case study, it is seen that the maximum power can actually be obtained at the optimal spring and damper condition, as predicted by the developed WEC theory. However, the band-width of high performance region is not necessarily the greatest at the optimal (maximum-power-take-off) condition, so it has to be taken into consideration in the actual design of the WEC.

Keywords

Acknowledgement

Supported by : Korea Institute of Energy Technology Evaluation and Planning(KETEP)

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