公铁两用钢桁梁桥接触网正馈线优化方案

Optimization Scheme of OCL Positive Feeder for Combined Highway and Railway Steel Truss Bridge

接触网正馈线是保障接触网可靠性的重要结构。以武汉天兴洲大桥为例,分析公铁两用钢桁梁桥正馈线故障特点,指出其根本原因是钢桁梁桥受温度变化影响导致正馈线弛度动态变化和桥梁结构净空限制,造成接触网承力索与正馈线、正馈线与公路桥梁体间有效绝缘距离不足。提出基于供电方式改变的临时修复方案和基于正馈线电缆优化的长期修复方案,对后者进行工程应用,实际效果表明:该方案可消除设备隐患,降低该区段接触网设备故障率,提高供电可靠性,保障供电质量。

The positive feeder is the main structure for ensuring the reliability of OCL（overhead contact line）. Taking Tianxingzhou Bridge in Wuhan as an example, the fault characteristics of the positive feeder for combined highway and railway steel truss bridge are analyzed. The basic reason is that the dynamic changes of the positive feeder and the clearance of the bridge structure are caused by the temperature change of the steel truss bridge, resulting in insufficient insulation distance between the catenary bearing cable and the positive feeder, the positive feeder and the public bridge. A temporary repair plan based on the power supply mode change and a long-term repair plan based on the positive feeder are put forward. The practical effect of the latter in engineering application shows that the scheme can eliminate hidden danger of equipment, reduce the failure rate of OCL equipment, improve the reliability of power supply and guarantee the quality of power supply.