基于小波变换的弓网接触压力特征研究

Study on Pantograph-catenary Contact Force Characteristics Based on Discrete Wavelet Transform

受轮轨振动及气动激扰等因素的影响,接触网波动和受电弓振动随列车运行速度的提高而加剧,接触压力的分布规律变的复杂,尤其是在周期特征和吊弦点处出现不同程度的改变。为了研究接触压力变化,基于有限元法,建立弓网仿真模型,得到弓网接触压力。采用离散小波变换,提取出跨距分量、吊弦间距分量及高频分量,分析接触压力的周期特征和奇异特征。分析接触网线索张力和线密度等参数对接触压力特征的影响。结果表明:接触网线索张力和线索线密度增大,可以增大接触压力跨距周期分量;增大接触线张力、减小承力索张力和线索线密度可以减小吊弦间距周期分量及吊弦点处接触压力的奇异性。

With the increase of train running speed,the catenary fluctuation and pantograph vibration are intensified under the influence of wheel-rail vibration and aerodynamic disturbance,causing more complicated pantograph-catenary contact force.In particular,the periodic characteristics of the contact force and the mutation at the dropper point change.To study the variation of the contact force,firstly the pantograph-catenary simulation model was established based on the FEM in this paper to obtain the pantograph-catenary contact force.Secondly,the discrete wavelet transform was used to decompose the contact force and extract the characteristic components such as span component,dropper spacing component and high-frequency component to analyze the periodic characteristics and singularity characteristics of the contact force respectively.Finally,the influence of parameter change on contact force was analyzed by changing the tension and linear density of the catenary.The results show that the span component of contact force can be increased by increasing the tension and linear density of the catenary.Increasing the contact wire tension,reducing the messenger wire tension and the linear density of the catenary can reduce the dropper spacing component and the singularity at the dropper point.