Vibration Mitigation of the Barge-Type Offshore Wind Turbine with a Tuned Mass Damper on Floating Platform

浮动平台内TMD对Barge式海上浮动风机的振动抑制研究

School of Aeronautic, Northwestern Polytechnical University, Xi'an 710072, China

Received: 12 May 2017

Abstract

This paper evaluates the application of a passive control technique with a tuned mass damper on platform for the barge-type offshore wind turbine. First of all, the three degrees of freedom mathematical model for the floating wind turbine is established based on Lagrange's equations, and the Levenberg-Marquardt algorithm is adopted to estimate the parameters of the wind turbine. Then, the method of frequency tuning which is utilized in engineering projects and genetic algorithm are employed respectively to simulate the optimum parameters of the tuned mass damper. The vibration mechanism about the phase-angle difference between tuned mass damper and floating platform is analyzed. Finally, the dynamic responses of floating wind turbine with/without tuned mass damper are calculated under five typical wind and wave load cases, and the vibration mitigation effects are researched in marine environment. Partial ballast is substituted by the equal mass of tuned mass damper due to the mass of floating platform with tuned mass damper would increase obviously, which would change the design of the wind turbine, and the vibration mitigation is also simulated in five typical load cases. The results show that the suppression rate of standard deviation of platform pitch is up to 47.95%, after substituting the partial mass of ballast, the suppression rate is 50%. Therefore, the dynamic responses of the barge-type floating wind turbine would be reduced significantly when the ballast is replaced by the equal mass of the tuned mass damper on floating platform.

摘要

在Barge式浮动风机的平台内配置调谐质量阻尼器（TMD），首先建立了海上浮动风机的三自由度动力学简化模型，并分别采用工程调频法和遗传算法（GA）寻求最优TMD参数；然后通过计算5种典型风浪载荷工况下有/无TMD的浮动风机的动态响应，研究了TMD在真实海洋环境中对风机的抑振增稳效果；最后在不改变Barge式浮动风机原设计的前提下，将风机部分压舱物等质量替换为TMD，研究了TMD在5种工况下的减振性能。结果表明：最优参数的TMD可使浮动平台俯仰角标准差的抑制率达到47.95%；用TMD替换部分压舱物后，平台俯仰角的减振率可达50%。因此，平台压舱物等质量替换为TMD后，可显著减少风机关键部位的振动响应及载荷。