Vibrations and Their Control in Floating Offshore Wind Turbines

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K06229
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Dynamics/Control
• Research Institution: Hiroshima University
• Principal Investigator: IKEDA Takashi 広島大学, 工学研究科, 名誉教授 (50115523)
• Co-Investigator(Kenkyū-buntansha): 原田 祐志 愛知工業大学, 工学部, 准教授 (00456691)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 振動工学 / 浮体式洋上発電風車 / 浮体式プラットフォーム / 風車ブレード / 制振 / 回転体の振動 / 係数励振振動 / 局在化現象

Outline of Final Research Achievements

This research theoretically and experimentally investigated the vibrations of floating offshore wind turbines and proposed some ideas of their control. In the blades of such wind turbines, parametrically excited vibrations might appear in the flapwise or chordwise direction because the platforms were subjected to vertical or horizontal motion due to ocean waves. When the three blades and the tower were coupled with each other, localization phenomena might occur in the blades which vibrated in different amplitudes. It was interpreted by analyzing the vibrations in a nonlinear oscillator array that the localization phenomena occurred when multiple vibrational modes simultaneously appeared. it was shown that liquid dampers and pendulum-type dynamic absorbers were effective in order to suppress the vibrations of the platform and blades, respectively.

Free Research Field

機械力学

Academic Significance and Societal Importance of the Research Achievements

浮体式洋上風車のブレードには，回転中に加わる重力の作用が周期的に変動し，かつ波浪による上下運動が作用するため，複雑な振動が発生する可能性が示されたことは学術的意義が大きい．また，風車プラットフォームやブレードの振動の制振対策として，液体ダンパーや振子型動吸振器が有効であることが示されたことは，今後，多くの浮体式洋上風車が導入されることが予想されることを考えると，信頼性・安全性の高い風車の開発，および国際的産業競争力の強化に貢献することができ，社会的意義も大きい．