基于新型TMD的水电站厂房结构振动控制研究

Novel methodology of structural vibration control for hydropower house based on tuned mass damper

机组振动通常引起水电站厂房结构高阶模态共振,威胁水电站安全。针对水电站厂房结构较高阶模态振动问题,提出了基于调谐质量阻尼器(TMD)的振动控制方法,并设计了一种新型高频TMD控制器,开展了2层钢框架减振试验,研究其在高频简谐激励和窄带扫频激励下的减振效果。结果表明:新型TMD控制器能有效控制结构较高阶模态,其中附加TMD-3作用下的振动控制效果最好,结构顶层峰值加速度衰减率达到94.12%,一层峰值加速度衰减率达到95.55%;当TMD调谐频率偏离结构较高阶模态时,减振效果逐渐减小,但仍呈现出较好的减振效果,说明新型TMD调谐频率更宽,具有一定鲁棒性;当激励频率变宽时,随着调谐频率接近受控频率,减振效果最佳,但偏离受控频率时,鲁棒性变差。

The vibration of power generating units usually causes resonances in high-order modes of the powerhouse structure of a hydropower station and threatens its safety.Aiming at this issue,a vibration control method based on the tuned mass damper(TMD)is presented.A new type of high-frequency TMD controller is designed,and tests are conducted on the vibration reduction of a two-story steel frame,focusing on the damping effect under high-frequency harmonic excitation and narrow-band sweep excitation.The results show that this controller effectively controls the high order modes of the structure and its control effect is best when TMD-3 is added,achieving an attenuation rate of peak acceleration of 94.1%at the top of the structure,and 95.6%in the first layer.As the TMD tuning frequency is lowered from the high-order modes,the damping is decreased gradually,but its effect remains satisfactory.This indicates that the new TMD tuning frequency band is wider and has a certain robustness.For wider excitation frequencies,the damping effect is the best when the tuning frequency is close to the controlled frequency,but the robustness worsens when it deviates from the controlled frequency.