高速铁路受电弓/接触网机械电气相互作用损伤机理研究

Pantograph-caternary system is a comprehensive coupling system of various integrated factors in mechanical, electrical and materials field. Its good performance plays a fundamental role in the reliability and safety of high-speed locomotives. With the substantial increase in train speed and popularity of double pantograph, damages under the multi coupling factors have gradually become a decisive factor in the service performance evolution of pantograph and caternary. Up to now, it has been less than five years since China''s high-speed railways began to service the public. It is precisely because of the scarcity of damage theory under multiple factors of mechanical, electrical and materials that results in inadequate consideration in the design, operation and maintenance procedures in the pantograph-catenary system. The service performance of the pantograph-catenary system declines rapidly which leads to frequent failure and accidents. To guarantee the long-term service performance of pantograph-catenary system in high-speed railways, the vibration laws of pantograph-catenary system and its corresponding effects on electrical characteristics are systematically studied taking full consideration of integrated factors in mechanical, electrical, materials and other aspects. The damage mechanism is proven which is caused by combined effects of mechanical shock, current-carrying friction and arc erosion in pantograph-catenary system. The mechanical and electrical damage theory of pantograph-catenary system is established. At last, it is expected to master key techniques to improve the service performance of the pantograph-catenary system.

弓网系统是一个集机械、电气、材料等多种因素于一体的复杂耦合系统，其良好的服役性能是保障高速列车可靠、安全运行的基本条件。随着列车运行速度的大幅度提高和双弓系统的普遍应用，多因素耦合作用下的损伤已逐渐成为弓网服役性能演化的决定性因素。我国高速铁路运行尚不足5年，由于缺乏“机械、电气、材料等多因素联合作用的弓网系统损伤”的理论，其设计、运行、维护过程中对这些因素考虑不足，弓网系统服役性能快速下降，导致故障、事故频繁发生。为保障高速铁路弓网系统的长期服役性能，本项目拟综合机械、电气、材料等因素，从系统角度研究高速铁路弓网系统波动规律及其对电气特性的影响，探明机械冲击、载流摩擦、电弧烧蚀等共同作用对弓网系统的损伤机理，建立弓网系统的机械电气损伤理论体系，掌握提高弓网服役性能的关键技术。

弓网系统是高速列车能量供给的唯一途径，其良好的服役性能是保障高速列车安全和可靠运行的基本条件。随着高速列车运行速度的不断提高，弓网系统振动加剧、弓网电弧频发、弓网系统电接触状态恶化，严重影响弓网系统的使用寿命与受流质量。本课题通过对高速铁路弓网系统机械、电气损伤机理的研究，为提高弓网系统服役性能提供理论基础。主要研究内容及结果如下：. 在弓网系统电接触特性方面：探明了接触电阻随接触压力、运行速度和牵引电流的变化规律，建立了弓网接触电阻模型，为选取合适的弓网接触压力提供了理论依据；探明了不同热源对滑板温升特性的影响，发现了电效应对滑板温升占据主导作用；建立了弓网系统电动力模型，研究了牵引电流、拉出值对弓网电动力的影响，为建立完整的弓网力学系统提供了有力补充。. 在弓网系统损伤规律方面：建立了弓网电弧MHD模型，研究了不同条件对电弧弧柱、接触线和滑板温度场分布的影响，通过增大接触线半径可降低弓网系统的电气损伤；探明了电弧烧蚀对滑板材料的损伤规律，发现了铜制颗粒是弓网磨粒磨损的来源之一；建立了弓网电弧等离子体参数的光学诊断平台，探明了电弧等离子体的组分与温度参数范围，可通过弓网电弧光谱信息反映电弧烧蚀强度；研究了弓网电弧及振动对磨损率的影响规律，通过增加法向载荷能够抑制电弧放电，降低其磨损率；提出了高温剥层磨损和电弧烧蚀的损伤机制和物理模型，发现脆性剥落和撕裂是不同条件下滑板损伤的共性影响因素。. 在弓网系统状态识别与服役性能改进方面：提出了快速、定量检测弓网电弧强度/烈度信息的有效方法；研究了不同弓网配副材料转移率对材料磨损率的影响，可通过材料转移率来评估滑板磨损量；建立了碳滑板磨损量的预测模型，评估其使用寿命；建立了高速列车牵引传动仿真模型，研究了离线时间对牵引系统电气特性的影响，探明了在不同运行速度发生离线时的中间直流环节电压跌落过程，为弓网离线时间标准的制定提供了依据。