地铁车辆弓网静态电接触的多场耦合模型及温升分析

Multi-field coupling modeling and temperature rise analysis for the static pantograph-catenary electrical contact of metro trains

当地铁到站或在线路上因故临时停车时,接触网仍需为列车提供电流,此时弓网接触部件因处于静止状态而存在局部过热的情况,严重时可能导致滑板热损伤甚至造成接触线断线事故。因此,地铁停车期间弓网电接触的温升研究具有重要意义。地铁列车弓网接触是热、力、电多物理场耦合的复杂行为,而弓网接触力、滑板热导率和接触线截面形状对弓网电接触有重要影响。本文针对受电弓滑板与接触线静态取流的工况,研究了接触电阻和接触热导的变化规律与建模方法,建立了热-力-电耦合的三维有限元分析模型,分析弓网接触力、滑板材料热传导率以及接触线磨耗对接触温升的影响。结果显示,增大弓网接触力、选用高热导率的滑板材料和改良接触线截面轮廓均可降低弓网接触温升。研究结果对接触线结构优化、滑板材料的选取及保障列车安全运行有重要参考价值。

Since the catenary still needs to supply current for the trains stopping at stations or stopping temporarily on the track for some reasons,the pantograph-catenary contact part in a stationary state may suffer from overheat,which may lead to a thermal damage of the contact strip and even cause a catenary breakage accident.Therefore,the study on the temperature rise at the pantograph-catenary electrical contact during stopping of metro trains is of great importance.The pantograph-catenary contact is a very complex interaction of multi-physical field coupling including thermal,mechanical and electrical behaviors,and the contact force,thermal conductivity of the contact strip and sectional shape of the contact wire have an important impact on the pantograph-catenary electrical contact.In this study,the change rules of contact resistance and thermal contact conductance,and the modeling approach were explored for the static current condition of the contact strip and contact wire;a three-dimensional finite element model was established for the thermal-mechanical-electrical coupling;the effects of pantograph-catenary contact force,thermal conductivity of the contact strip and wear of contact wire to contact temperature rise was studied.The results show that the pantograph-catenary contact temperature rise can be reduced by increasing the contact force,selecting the strip material with a high thermal conductivity and improving the sectional shape of contact wire.The study results may be used as reference for the structural optimization of contact wire,selection of strip materials and guarantee of trains safe operation.