钢轨电位相关影响因素现场测试及分析

Field Test and Analysis of Influencing Factors of Rail Potential

国内城市轨道交通线路运营过程中,经常出现钢轨电位过高,导致钢轨电位限制装置频繁动作,甚至直流框架保护动作,大面积直流停电。钢轨电位过高会对乘客人身安全造成威胁,同时,屏蔽门跟钢轨连接,钢轨电位传导到屏蔽门,当结构钢筋和屏蔽门触碰时就会发生放电,产生火花,存在严重的安全隐患。针对钢轨电位过高的问题,对钢轨电位相关影响因素,如钢轨纵向电阻、轨缝电阻、机车牵引电流、钢轨电位变化情况进行了现场测试及分析,同时,对屏蔽门机车绝缘部分绝缘情况、及等电位连接线拆除后屏蔽门电位进行实际测试。经过分析提出钢轨电位限制措施,屏蔽门安全解决方案。

During the operation of domestic urban rail transit lines,the rail potential is often too high,which leads to the frequentaction of the Rail Over-Voltage Protection Device,even the DC frame protection action and the large area DC power failure.The railpotential is too high will pose a threat to the safety of passengers,while the connection of shield door with the rail,the rail potentialconduces to the shield door,when the structural steel and shielded doors touch there will be discharge and spark,which has serious securityrisks.In view of the problem that the rail potential is too high,the influence factors,such as rail longitudinal resistance,track resistance,locomotive traction current and rail potential change,are tested and analyzed.At the same time,the actual test of the insulation situation ofthe shielded door locomotive insulation and the shielded door potential after removal of equipotential connection cable are carried out.Afterthe analysis,the rail potential limit measures and shielding door security solutions are proposed.