直流制式牵引供电对信号设备的干扰问题分析和解决

以西宁至格尔木复线中锡铁山车站为例,分析了直流制式牵引供电模式下97型25 Hz相敏轨道电路故障产生红光带原因.实验结果表明通过安装调整内部气隙后的扼流变压器,轨道电路故障解除,红光带消失,测试轨道电路参数满足其电气要求和极限传输长度.研究表明：不平衡电流中的直流成分过大会引起扼流变压器铁心直流磁化,使其激磁阻抗减少,导致轨道继电器端电压降低后错误落下,通过调整扼流变压器的内部气隙就可以解决这一类问题.

Analysis and Resolution on Interference Problem of DC Traction Power Supply System to Signaling Devices

Xitieshan Station on Xining-Geermu double track railway is taken as an example to analyze the situation of track-sector circuit interfered by DC power of electric traction, which causes interlocking mal- function known as track circuit red band. Experimental results show that after the installation of the choke transformer in which the internal air gap has been adjusted, the track circuit failure can be solved, the red band disappeared and the track circuit parameters measured correspond with the electrical requirements and the maximum transmission length. The research indicates that the excessive DC current proportion in the unbalanced current will originate the magnetization of choke transformer DC, lead to magnetizing imped- ance decrease and cause the incorrect fall of the track relay,and these problems can be solved by adjusting the internal air gap of the choke transformer.