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Design of Wave Energy Extractor with a Linear Electric Generator -Part I. Design of a Wave Power Buoy

선형발전기가 탑재된 파랑에너지 추출장치 설계 -I. 파력 부이 설계

  • Kim, Jeong Rok (Department of Ocean System Engineering, Jeju National University) ;
  • Bae, Yoon Hyeok (Department of Ocean System Engineering, Jeju National University) ;
  • Cho, Il Hyoung (Department of Ocean System Engineering, Jeju National University)
  • 김정록 (제주대학교 해양시스템공학과) ;
  • 배윤혁 (제주대학교 해양시스템공학과) ;
  • 조일형 (제주대학교 해양시스템공학과)
  • Received : 2014.04.04
  • Accepted : 2014.05.16
  • Published : 2014.05.25

Abstract

Design procedure of WEC (wave energy converter) using the heaving motion of a floating cylinder-type buoy coupled with LEG (linear electric generator) system is introduced. It is seen that the maximum power can actually be obtained at the optimal conditions ($c_{PTO}=b_T$, ${\omega}={\omega}_N$). Then, based on the developed theory, several design strategies are proposed to further enhance the maximum PTO (power take off), which includes the intentional mismatching with the heave natural frequency, which is 15% higher value than the peak frequency of input velocity spectrum. By using the intentional mismatching strategy, the generated power is actually increased and the corresponding draft as well as the required PTO damping value is significantly reduced, which is a big advantage in manufacturing the WEC with practical LEG (linear electric generator) system.

선형발전기와 연성된 원통형 부이의 수직운동으로부터 파랑에너지를 추출하는 파력발전장치의 설계과정을 소개하였다. 최대 파워는 최적조건($c_{PTO}=b_T$, ${\omega}={\omega}_N$)에서 발생하며, 공진조건시 부이의 수직운동 고유주파수와 속도스펙트럼의 피크 주파수를 일치시키지 않고 의도적으로 고유주파수를 15% 크게 설정하면 추출파워의 최대값을 더욱 높일 수 있다. 이러한 방법을 통하여 추출 파워의 증가와 함께 부이의 흘수를 낮추고 동시에 PTO 감쇠력을 줄일 수 있기 때문에 발전장치 제작 비용을 낮출 수 있는 부수적인 효과를 얻을 수 있었다.

Keywords

References

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