基于自供电磁流变阻尼器的斜拉索减振理论与试验研究

Effective vibration control technology for stay cables is extremely critical to safe operations of cable-stayed bridges. The main span of cable-stayed bridges has been above a thousand meters, in which the longest stay cable can be more than 500 meters. Vibration control of super-long stay cables is more difficult than that of short cables. For super-long cables, passive control can not provide sufficient damping since its installation height is restricted to a low level. In theory active control can obtain good control performance, but it requires too much external energy. Semi-active control based on magneto-rheological (MR) dampers is quite promising but still with external power supply. This project aims to develop new mitigation technology for stay cables based on self-powered MR dampers. Its key idea is to develop high-efficient vibration energy harvesting motors, which can make MR dampers be free from dependence on the external power supply. As a result, vibration control system based on self-powered MR dampers is realized. On the one hand, to improve the control performance of stay cables, semi-active control or smart passive control in this system can be achieved with the combination of sensing abilities of motors, velocity feedback control as well as negative stiffness control. On the other hand, control performance of stay cables with high modes can also be enhanced by passive electromagnetic damping induced from motors themselves.

斜拉索的有效减振技术，对斜拉桥的安全运营至关重要。斜拉桥已进入千米级时代，最长斜拉索超过500 米。相对短索，超长斜拉索的振动控制尤为困难。被动控制由于受阻尼器安装高度的限制难以提供足够的阻尼，理论上控制效果较好的主动控制所需能量又太大，而富有前景的磁流变(MR)阻尼器半主动控制也需要一定的外界电源供给。本项目拟研发基于自供电MR 阻尼器的斜拉索减振新技术。其核心思想是基于电磁式振动能量回收技术研制高效的拉索振动能量回收电机，使得MR阻尼器摆脱对外部电源的依赖，形成自供电MR 阻尼器拉索减振系统。该系统一方面利用能量回收电机的传感功能，并结合速度反馈与负刚度控制算法实现MR阻尼器的半主动控制或智能被动控制，以增强斜拉索的整体减振效果；另一方面利用能量回收电机的附加被动电磁阻尼，重点增强拉索的高阶模态减振效果。

斜拉索的有效减振技术，对斜拉桥的安全运营至关重要。斜拉桥已进入千米级时代，最长斜拉索已接近600米。相对短索，超长斜拉索的振动控制尤为困难。被动控制由于受阻尼器安装高度的制约难以提供足够的附加阻尼，目前超长斜拉索较多采用基于MR阻尼器的半主动控制系统来解决这一问题。与主动控制相比，虽然MR阻尼器半主动所需要的能量较低，但仍需要外界电源供给，给实际工程应用带来不便。本项目围绕斜拉索减振新技术开发与减振效果提升，按照研究计划完成了：（1）基于振动能量回收的自供电MR阻尼器系统集成与性能试验研究；（2）基于自供电MR阻尼器的超长斜拉索减振仿真分析、面向实桥斜拉索减振的自供电MR阻尼器设计流程；（3）基于自供电MR阻尼器的模型斜拉索减振试验研究与减振机理分析。. 依托项目主要研究成果合计16项，包括：期刊论文11篇（EI收录期刊5篇、中文核心期刊5篇）；国家发明专利授权4项、实用新型专利授权1项。研究表明：自供电MR阻尼器斜拉索减振工程应用可行性强，能量回收电机作为被动电磁阻尼器对增强斜拉索的高阶模态减振效果显著，为超长斜拉索的减振理论与技术发展提供了重要研究基础。本项目主要贡献在于：构建了由旋转式能量回收电机与仅需较小能量供给的MR阻尼器集成的自供电MR阻尼器减振系统，并通过试验与仿真分析阐明了自供电MR阻尼器的可行性、优越性与减振机理，实现了结构振动控制与结构振动能量回收的有机结合；综合自供电MR阻尼器对斜拉索减振的仿真分析与模型试验研究，形成了自供电MR阻尼器斜拉索减振设计方法与技术；揭示了自供电MR阻尼器斜拉索减振系统具有的被动负刚度特性产生机理及其对提升斜拉索减振效果的重要作用。.