以某地铁线路及其临近的埋地长输管道为测试研究对象,开展了4种不同轨电位限制装置(OVPD)运行工况下管道和轨道电参数的同步测试,分析了OVPD对埋地管道杂散电流干扰的影响规律,同时明确了轨地电位和轨地间流经电流的分布变化。结果表明:设备合位时,轨地间流经电流峰值大于1 000 A,两个站设备同时合位时,电流峰值增加约60%;供电区间内一端OVPD合位,另一端轨地电位略有降低;轨道与管道交叉点临近的OVPD合位时,影响范围内的管道电位正/负向偏移量均呈现增大的趋势,杂散电流流入/流出时间分布无明显变化,而远处OVPD合位时,管道杂散电流流出时间比例减小明显,约4 km外管道电位整体负向偏移,管道正向偏移和流出电流密度被抑制;轨道与管道交叉点临近的OVPD对于管道电位正向偏移影响程度大于远处OVPD,而对电位负向偏移的影响则刚好相反。

Taking a metro line and adjacent buried long-distance pipeline as the testing object, the pipeline and track electrical parameters under 4 kinds of over-voltage protection device (OVPD) operating conditions was simultaneously tested. The influence rule of OVPD on the stray current interference on buried pipelines was analyzed, and the distribution rule of rail-to-ground potential and flowing current between rail and ground were clarified. The results show that when the equipment was switched on, the peak current flowing between rail and ground was greater than 1 000 A; the current peak value increased by about 60% when two OVPD were switched on at the same time. When one of OVPD at two ends of a power supply interval was switched on, the rail-to-ground potential at the other end slightly lowered. When the OVPD near the intersection of the rail and the pipeline was switched on, the positive/negative offset of the pipeline potential showed an increasing trend, and the time distribution of inflowing and outflowing stray current did not change significantly; while the remote OVPD was switched on, the proportion of stray current outflow was significantly reduced, and pipeline potential beyond 4 km overall negative shifted, positive offset of the pipeline potential and outflowing current density were suppressed. The OVPD near the intersection of rail and pipeline had a greater effect on the positive offset of the pipeline potential than the remote one, while the effect on the negative offset of the pipeline potential was just the opposite.