受电弓滑板磨耗测量算法的研究

将数字图像处理技术应用于受电弓滑板磨耗测量,提出一种受电弓滑板磨耗测量算法,结合边缘提取、形态学图像处理、Hough变换、聚类分析等方法,实现从图像上测量计算出受电弓滑板实际磨耗厚度.该算法由起点定位、边缘跟踪和厚度计算构成.其中,起点定位用于确定滑板上下边缘的起点坐标;边缘跟踪结合Sobel算子和Canny算子的优点获取滑板磨损面的边缘信息;厚度计算利用物-像固定比值计算滑板磨耗厚度,并采用均值方法提高测量精度.     

空气动力作用对高速受电弓受流特性影响研究

从空气动力学角度出发,分析高速弓网受流稳定性。利用三维建模软件UG,建立了高速受电弓的几何模型,将受电弓的几何模型导入流体力学计算软件STAR-CCM＋,采用紊流模型对受电弓在开放空间的空气动力学性能进行了仿真,研究了高速350km/h下风阻对弓网之间抬升力、受电弓弓头和杆件的影响情况,为进一步研究高速受电弓参数和受流性能提供了仿真手段和理论研究基础。     

基于疲劳寿命分析的地铁受电弓上框架改进

文章分析了地铁受电弓运行过程中导致上框架焊缝开裂的主要影响因素,采用增加加强筋的方式,降低焊缝区域应力,提高焊接处疲劳寿命。运用Matlab和ANSYS软件进行静力学和强度计算,根据疲劳强度曲线进行对比分析。分析结果表明:增加加强筋后,集中应力下降了36.4%,疲劳寿命是结构修改前的3.86倍。     

高速铁路自然过分相方案

在深入研究机车带负荷过分相产生电弧机理的基础上,提出了自然过分相技术方案.该方案的基本原理是在车载变压器高压侧和牵引供电臂末端分别并联一个电容,当机车过分相时,牵引网和车载电气传动系统实现等电位分离,避免了机车过分相时产生电弧.自然过分相方案和现在使用的3种方案相比,具有过分相断电时间短,结构简单,投资少,运行维护量小等优点.自然过分相方案还能大幅度降低机车运行时离线电弧的强度.     

基于弓网电弧动态模型的高速列车弓网电弧产生机理

分析了高速列车弓网电弧产生的机理,结合受电弓和接触网间的离线时间、材料缺陷、电腐蚀等问题,解析了弓网电弧与高速列车安全的关联机制。依据电弧理论的动态模型算法,推导了Cassie模型和Mayr模型的理论公式,并论述了这两种模型的适用条件和应用范围。提出了高速列车弓网电弧方面目前仍存在的问题及未来电弧研究的展望。     

Influence of the aerodynamic forces on the pantograph–catenary system for high-speed trains

Most of the high-speed trains in operation today have the electrical power supply delivered through the pantograph–catenary system. The understanding of the dynamics of this system is fundamental since it contributes to decrease the number of incidents related to these components, to reduce the maintenance and to improve interoperability. From the mechanical point of view, the most important feature of the pantograph–catenary system consists in the quality of the contact between the contact wire of the catenary and the contact strips of the pantograph. The catenary is represented by a finite element model, whereas the pantograph is described by a detailed multibody model, analysed through two independent codes in a co-simulation environment. A computational procedure ensuring the efficient communication between the multibody and finite element codes, through shared computer memory, and suitable contact force models were developed. The models presented here are contributions for the identification of the dynamic behaviour of the pantograph and of the interaction phenomena in the pantograph–catenary system of high-speed trains due to the action of aerodynamics forces. The wind forces are applied on the catenary by distributing them on the finite element mesh. Since the multibody formulation does not include explicitly the geometric information of the bodies, the wind field forces are applied to each body of the pantograph as time-dependent nonlinear external forces. These wind forces can be characterised either by using computational fluid dynamics or experimental testing in a wind tunnel. The proposed methodologies are demonstrated by the application to real operation scenarios for high-speed trains, with the purpose of defining service limitations based on train and wind speed combination.     

电力机车受电弓发展综述

电力机车速度不断提高导致弓网电弧加剧,已经严重制约了高速铁路的发展.本文从受电弓的结构和滑板材料角度阐述国内外电力机车减小弓网电弧危害的现状以及发展,并分析了受电弓滑板的发展趋势.最后从电气角度分析了弓网电弧的产生机理,指出在现有的机械手段的基础上还应结合弓网电弧的电气特性进行研究,从而找到抑制和消除弓网电弧的方法.     

广州地铁二号线列车受电弓碳滑板异常磨耗分析

分析了可能造成广州地铁二号线列车受电弓碳滑板出现异常磨耗问题的原因,确定造成碳滑板异常磨耗的因素主要包括:接触网布置的均匀性及受电弓弓头结构、升弓保持力等。     

Dynamic assessment of existing soft catenary systems using modal analysis to explore higher train velocities: a case study of a Norwegian contact line system

Significant advances made on the rolling stock have considerably increased the possibility of higher speeds in existing railways. Thus, it is important to explore higher speeds and potential limiting factors of existing soft catenary systems. The present paper investigates procedures to assess the dynamic behaviour of these systems using response sampling and modal analysis. The assessment evaluates and quantifies dynamic response along the section. To verify the approach, a case study is conducted and the following assessment methods are used: lengthwise track correlation estimating dynamic predictability, power spectral density estimations before and after passage and short-time Fourier transforms and spectrograms. The combination provides detailed information on the dynamic behaviour. The first part introduces necessary considerations for suggested modal analysis. The second part describes an existing Norwegian section. The case study is conducted using a finite element model including a straight and a given section between Oslo-Trondheim, providing detailed evaluations and system limitation detections.     

120km/h地铁列车受电弓肘接部裂纹分析与改进

针对120 km/h地铁列车在运营过程中多次出现受电弓上框架肘接部位裂纹的现象,分析其故障原因,提出采用管对管焊接处加入加强筋板的改进方案。通过力学分析以及实践运用,验证了改进方案的有效性。