调谐质量阻振变刚度控制器设计及其效果研究

Study of Semi-Active Controller and Its Effect on Offshore Platform Based on Variable Stiffness Tuned Mass Damper

提出了一种新的变刚度半主动控制方法 ,输入随机波面特征信息 ,得到平台甲板加速度响应谱 ,经计算机处理后得到实时控制信号 ,达到控制装置对系统最优状态的跟踪。给出基于调谐质量阻尼器变刚度半主动振动控制的控制器设计方案 ,验证了以平台甲板加速度信号为输入时控制系统对平台振动的抑制效果 ,该控制方案可克服数据处理系统和作动器的延时带来的系统稳定性问题。计算结果表明 ,平台甲板加速度振动控制效果可达 2 0 %以上。

The purpose of this paper is to investigate the control effect of a semi active vibration absorber developed for an offshore platform,and a scheme of a vibration control system is also designed. The vibration of the structure is suppressed by installing a new and innovative variable stiffness tuned mass damper (VSTMD) on the top deck of the platform. Under the action of irregular wave forces, the deviation of the acceleration response of the top deck is used as the cost function. To make the control system feasible and easy to operate, a new methodology is developed. The acceleration of the top deck is used as the input and an experienced formula is used to determine the optimum stiffness of the VSTMD. Result of the analysis demonstrates that under the action of the sea states measured in Mexico Gulf in 1996, the deviation of the deck acceleration can be reduced by an average of 20% or above compared with that without VSTMD. The result indicates that VSTMD device can provide a reliable and inexpensive means to mitigate the structural vibration for the offshore engineering.