基于车体模态振动提取方法的高速动车组车体减振设计

Vibration Reduction Design of High-speed EMU Car Body Based on Modal Vibration Decomposition Method

高速动车组车体的弹性振动控制对车辆运行品质的提升具有重要意义,依据车体主要弹性模态振动贡献,一种借由现有不同悬挂设备作为动力吸振器,且通过对设备的悬挂参数设计实现车体精准弹性振动控制的方法被提出。基于模态叠加理论,提出基于奇异值分解(Singular value decomposition,SVD)及最小二乘拟合的模态振动提取方法,将动车组车体物理振动解耦为模态振动,提取出车体各阶模态振动。分析不同车体模态对车上、车下设备安装位置处振动的贡献,据此,将设备考虑为动力吸振器,确定各设备所要制振的目标车体模态。采用固有模态法,辨识制振的目标车体模态在各设备安装位置处的等价质量,基于动力吸振理论,设计各设备的垂向和横向最优固有频率及阻尼比,并通过仿真试验对振动控制效果进行验证。结果表明,基于动力吸振的设备减振设计能够有效降低目标模态的振动,提高车辆运行平稳性。同时,在设备最优阻尼比作用下,作为动力吸振器的设备自身振动并不剧烈。

Vibration control of flexible car body of high-speed EMUs is of great significance for improving ride quality.Based on the contribution of elastic modal vibration of the car body,a method of precise elastic vibration control of the car body is proposed by using different existing suspension equipment as dynamic vibration absorber and designing suspension parameters of the equipment.Based on the modal superposition theory,a modal vibration decompositionm method based on singular value decomposition(SVD)and least square fitting is proposed,which decomposes the physical vibration of a railway vehicle car body into modal vibration is proposed,and each order modal vibration of the railway vehicle car body is decomposed.The contribution of different car body modes to the vibration of the installation positions of the equipments on or under the vehicle are analyzed.Based on this,the equipments are considered as dynamic vibration absorbers,and the target car body modes to be controlled by each equipment is determined.By using the natural mode method,the equivalent mass of the target vehicle body mode to be controlled at the installation position of each equipment is identified.Moreover,based on the dynamic vibration absorption theory,the vertical and lateral optimal natural frequencies and damping ratio of each equipment are designed,and the vibration control effect is verified by simulation test.The results show that the vibration reduction design based on dynamic vibration absorption can effectively reduce the vibration of the target modes and improve the ride quality of the railway vehicle.At the same time,under the optimal damping ratio of the equipment,the vibration of the equipments as dynamic vibration absorbers are not severe.