【作者】 李霞；

【导师】 陈唐龙；

【作者基本信息】 西南交通大学 ， 电气工程（专业学位）， 2018， 硕士

【摘要】 随着电气化铁路的迅猛发展,人们对速度更快、更安全可靠的电气化铁路的期望也越来越大。接触网系统作为电气化铁路的重要组成部分,在实际运营过程中,接触网异常状态频频出现,严重影响了弓网间正常取流,进而降低了电气化铁路运营的可靠性。研究异常状态下的弓网受流质量,能够为接触网异常的危害程度提供判定依据,为接触网故障预测与定点维护提供参考,对提高接触网系统安全性具有重要意义。目前国内外学者主要针对接触网异常状态机理及现象进行研究,很少对异常状态给弓网受流质量带来的具体影响进行分析。本文将利用ANSYS建立接触网异常状态模型,通过接触力表征弓网受流质量,探究不同异常状态对弓网受流质量的影响,给出接触网异常状态判定的参考依据,并提出改进措施,改善弓网受流质量,提高接触网系统可靠性。针对工程实际中常见的接触网异常状态进行了简要介绍。基于ANSYS-APDL建立了简单链型悬挂接触网、刚性接触网以及锚段关节和刚柔过渡模型,利用接触对耦合办法实现了受电弓沿接触线的滑动。基于正常工况柔性接触网模型,仿真模拟接触线磨耗、吊弦断裂、吊弦脱落三类接触悬挂异常,发现接触线磨耗达初始接触线截面积28%时,弓网间受流质量明显变差;吊弦故障位置越靠近跨中,弓网受流质量越差;仿真模拟承力索底座松脱的支持装置异常,发现承力索底座脱落时,故障点附近无法正常受流;仿真模拟接触线和承力索张力参数异常,发现适当增大接触线和承力索张力能够有效提高弓网受流质量。针对刚性悬挂接触网,仿真分析了刚性接触网跨距变化对弓网受流质量的影响,发现在6m到10m跨距内,跨距越小受流质量越好,但也要考虑到跨距激励频率和接触网固有频率近似时,共振会使受流质量恶化的问题;仿真分析定位绝缘子松脱、锚段关节及刚柔过渡安装偏差对弓网受流的影响。研究发现:适当减小悬挂刚度能够有效提高弓网受流质量,当定位绝缘子松脱,悬挂刚度过小时,弓网受流质量将急剧恶化;锚段关节和刚柔过渡段是接触网系统的薄弱环节,安装偏差过大时弓网间将无法正常受流。提出通过安装弹性绝缘悬挂组件来改善弓网受流质量的方案。研究表明弹性绝缘悬挂组件不同布置方式对受流质量改善程度不同;在锚段关节和刚柔过渡处安装该组件能够有效改善受流质量,提高接触网对异常状态的包容度;在保证速度和受流质量的前提下,使用弹性绝缘悬挂组件能够增大接触网跨距,减少故障点,减轻施工维护工作量。更多还原

【Abstract】 With the rapid development of electrified railways,our expectations for faster,safer and more reliable electrified railways are increasingly growing.As a crucial part of the electrified railway,the overhead contact system has frequently appeared the abnormal status in the actual operation process,which has seriously affected the current collection between the pantograph-catenary and thus reduced the reliability of electrified railway operations.Studying the current collection quality of pantograph-catenary under the abnormal conditions is able to provide the basis for judging the extent of harm caused by the abnormality of the overhead contact line,providing the reference for fault prediction and fixed-point maintenance of the overhead contact line and has great significance for improving the security of overhead contact system.At present,scholars at home and abroad has mainly focused on the research of the mechanism and phenomenon of abnormal conditions of overhead contact line,while rarely made a quantitative analysis on the quality of the current collection quality of pantographcatenary.The thesis will establish an abnormal state model of overhead contact line with the help of ANSYS and explore the influence of different anomalies on the quality of pantograph-catenary by the contact force to characterize the current collection quality of pantograph-catenary,giving a reference for judging the abnormal conditions of overhead contact line and putting forward improvement measures to enhance current collection quality of pantograph-catenary and increase the reliability of overhead contact system.A brief introduction is made to the frequent abnormalities of overhead contact line in the practice of the project.A simple catenary suspension overhead contact line,a rigid overhead contact line,overlapping sections and rigid-flexible transition models were established based on ANSYS-APDL,and the sliding of the pantograph along the contact lines was achieved by coupling method.Based on the model of flexible overhead contact line under the normal conditions,the three types of contact suspension abnormalities such as contact line wearing,suspension string breakage,and suspension string falling off were simulated.It was found that when the wearing of contact lines reached 28% of the sectional area of initial contact lines,the current collection quality of the pantograph-catenary was significantly getting worse;the closer the suspension string located near the center,the poorer the quality of the pantograph-catenary;in the analogue simulation of the abnormalities of support device base loosening of the catenary wire,it can be found that the failure point cannot collect the current when the catenary wire base fallen off;in the analogue simulation of the parameters abnormalities of tensile structure between contact line and catenary wire,it was found that increasing the tension of contact line and catenary wire can effectively improve the current collection quality of pantograph-catenary.For rigid suspension overhead contact line,the impact of span variation of rigid suspension overhead contact line on the current collection quality of pantograph-catenary was simulated and analyzed.It was found that within a span of 6m to 10 m,the smaller the span was,the better the flow quality was,but the question that the resonance would degrade the current collection quality shall take into account when the span excitation frequency was close to the natural frequency of the overhead contact line.In the simulation of the impact of the looseness of the positioning insulator,overlapping sections and the installation deviation of the rigid-flexible transition on the current collection quality of pantograph-catenary,it is found that appropriate reduction in suspension stiffness can effectively improve the current collection quality of pantograph-catenary.When the positioning insulator loosened and the suspension stiffness was too small,the current collection quality of pantograph-catenary would deteriorate sharply;the overlapping sections and the rigid-flexible transitions were the weakness of overlap contact systems.When the installation deviation was too large,the pantograph-catenary would not be able to receive the flow normally.It is proposed to improve the current collection quality of pantograph-catenary by the installation of elastic insulating suspension components.Studies have shown that different arrangements of elastic insulating suspension components have different degrees of improvement in the quality of current collection;installation of the component at the overlapping sections and rigid-flexible transitions can effectively improve the quality of current collection and increase the tolerance of overhead contact line under the abnormal conditions;under the premise of ensuring speed and current collection quality,the use of elastic insulating suspension components can increase the span of overhead contact system,reduce the number of failure points,and decrease the workload of construction and maintenance.更多还原