城市轨道交通杂散电流防护失效原因及新型防护方案研究

结合城市轨道交通工程杂散电流产生的根源及传输路径，对目前常规采用的防护方法效果不佳的原因进行分析。针对杂散电流产生的源头，提出在钢轨绝缘扣件处，扩大并长期持续保证其绝缘爬距有效性；针对杂散电流的传输，提出有效阻断其非预期传输路径的新思路及方案，包括双绝缘节及定向回流方案等；对杂散电流的泄漏总量进行有效控制，实现城市轨道交通工程建设的可持续发展。

An Invalidation Analysis and New Protection Schemes of Stray Current to Urban Rail Transit

In this study, source and transmission path of stray current by conventional protection methods are analyzed for preventing unwanted stray currents in urban rail transit. To reduce the source of stray current, a new rail insulation protective sleeve method is proposed to enhance and maintain the effectiveness of the insulation creepage at the rail fastener in its life cycle. To cut off the path of stray current transmission, a new scheme is proposed to effectively block the unexpected transmission path, including the use of double insulation joints and directional return current methods. The total leakage of stray current was effectively reduced to realize the sustainable development of urban rail transit.