Evaluation and Mitigation Measures of AC Interference to Buried Pipelines by a Newly AC Electrified Railway Transmission System

A newly built AC electrified railway transmission system shares multiple spatial intersections and short-distance long-distance parallels with it's adjacent buried metal pipelines, which poses a risk of AC interference and corrosion to the pipelines. Based on the detailed field test and numerical simulation method, the risk of pipeline AC interference caused by the new electrified railway was evaluated, and interference protection measures were carried out. The results show that under the dynamic interference of electrified railway, the pipeline interference voltage was up to 6.8 V, and the pipeline AC interference current density up to 54.22 A/m², which required interference mitigation measures for the pipeline. After laying horizontal mitigation zinc strip, the maximum AC interference voltage and AC interference current density of the pipeline was reduced to 3.7 V and 29.3 A/m², which met the requirements of pipeline AC interference protection.