磁浮列车车-轨耦合自激振动机理及实验研究

The electromagnetic levitated (maglev) train utilizes attractive magnetic forces to neutralize its weight, thus the vehicle can be suspended above the guideway with no contact with the guideway. However, in some cases, when the train is suspended above the guideway without moving, the electromagnets of the train, together with the guideway, tend to vibrate in the vertical direction, and this phenomenon is called maglev vehicle-guideway coupled self-excited vibration. Generally, the amplitude of the self-excited vibration is rather large, and it may cause damages to the structure of the vehicle and the guideway, and it also makes the passengers feel uncomfortable. So far, the principle of the self-excited vibration has not yet been well studied; and in practice, the vehicle-guideway coupled self-excited vibration problem has not been solved, either. Based on the current research, taking the medium-low speed maglev train developed in China as the object, this project tries to investigate the principle of the coupled excited vibration via theoretical modeling, finite element analysis, as well as experimental validation, which intends to provide a reference for the construction of commercial maglev lines. In addition, to solve the self-excited vibration problem in the current maglev system, at least one method to suppress the self-excited vibration is to be developed in this project, which will also provide a safty enhancement for the commercial operation of the maglev system.

吸力型磁浮列车依靠电磁吸力抵消自身重力从而悬浮在轨道之上，但在某些情况下，当磁浮列车静止悬浮在某段轨道上时，磁浮列车的电磁铁和轨道会同时出现大幅垂向振动，这种现象被称为磁浮列车的车-轨耦合自激振动。这种振动的振幅往往较大，对轨道和车辆的结构损伤较大，同时会使乘客感到不适。目前国内外对于该问题的研究尚不够完善，车-轨耦合自激振动产生的机理还没有认识清楚；在工程上，车-轨耦合自激振动问题仍未得到很好解决。本项目在现有研究的基础上，以我国自主研发的中低速磁浮列车为研究对象，通过理论建模、有限元仿真以及实验验证等手段，研究磁悬浮列车车-轨耦合自激振动产生的机理，从而为磁悬浮列车商业化线路的修建提供依据。此外，依托实验条件，寻找至少一种抑制车-轨耦合自激振动的方法，为解决当前磁浮列车的耦合自激振动问题提供一种控制策略，同时也为磁浮列车的商业运营提供安全保障。

吸力型磁浮列车静止悬浮在某些轨道上时，由于轨道存在弹性，电磁铁和轨道可能会同时出现大幅垂向自激振动，严重危害车辆正常运行。本项目主要研究了如下问题：.(1) 完成了磁浮轨道的建模。本研究课题综合运用理论建模、有限元分析和试验模态分析等方法，结合当前磁浮试验线的轨道结构，建立磁浮系统支墩-轨道梁-轨排结构的轨道动力学模型；.(2) 通过分析系统的有源/无源特性来阐述车-轨耦合系统自激振动发生的机理，找到了车-轨耦合自激振动发生的条件。对于等幅自激振动，采用谐波平衡法分析自激振动的振幅和频率。.(3) 在唐山中低速磁浮试验线上进行了车-轨耦合自激振动试验，通过参数对比验证了自激振动机理分析的正确性。.(4) 研制完成了一套完整的车轨耦合共振试验平台，研制了配套的悬浮控制系统，该系统可以很好的模拟磁浮列车在弹性轨道上的车-轨耦合动力学问题，从而为研究磁浮列车车轨耦合共振问题提供了有力的帮助。.(5) 提出了一种基于虚拟动力吸振器方法的车轨耦合自激振动抑制方法，该方法可以在不改变轨道结构的情况下能够有效抑制车-轨耦合自激振动的控制方法。在车轨耦合共振试验平台上的试验表明，该算法可以有效抑制磁浮列车的车桥耦合共振问题。. 本项目从理论、试验层面研究了磁浮列车车轨耦合自激振动的发生机理，研制了一套车轨耦合共振试验平台，为解决当前磁浮列车的耦合自激振动问题提供一种控制策略，同时也为磁浮列车的商业运营提供安全保障。