Research On Electromagnetic Interference Characteristics Of AC Electrified Railways To Buried Oil And Gas Pipelines

The safety of railway transportation and pipeline transportation is very important,which are the vital economic lifeline of the country.However,Subject to geographical location,land resources and preferential principle of right of way and other factors,AC electrified railway and the oil and gas pipeline in the design and construction of practical engineering often choose the same transmission corridor laying.As the interference source,AC traction power supply system of electric railway have electromagnetic influence on the buried pipelines laid in the adjacent area,which seriously affects its safety and energy transportation.Therefore,the study of the mechanism of electromagnetic interference on buried oil and gas pipelines by AC electrified railways,analysis of the influence of different influencing parameters on the distribution characteristics of pipeline AC disturbances,and optimization of their interference protection design will be of great significance to reduce the influence of electrified railways on the interference of AC pipelines and ensure the safety of pipeline transportation and operation.The beginning of this paper,the electromagnetic coupling mechanism of an AC electrified railway to the buried pipeline is analyzed.At the same time,based on the theory of electromagnetic field coupling,the mathematical theoretical calculation model of the inductive coupled voltage and the resistive coupling voltage of the buried pipeline is derived.On this basis,combined with the structure parameters of the traction power supply system and buried pipeline,the electromagnetic coupling simulation model of the AC traction power supply system-buried pipeline is built by using the CDEGS simulation platform.The accuracy and accuracy of the simulation model is verified by verifying the impedance characteristics of the traction loop and comparing the simulation results with the theoretical calculation results.Secondly,for two different power supply methods of AC electrified railways(direct power supply and AT power supply),the influence of different parameters on the distribution characteristics of the AC interference of buried pipelines is analyzed by simulation and calculation.,which includes locomotive position,load characteristic,single compound line,traction network structure,rail leakage resistance,pipeline anticorrosion coating,pipe parallel length,pipe parallel spacing,pipe crossing angle and soil resistivity.Meanwhile,the sensitivity of the AC interference voltage extremum to the above parameters is obtained.Finally,for the shielding protection measures such as shielding net and drain grounding pole,the effects of different shielding net setting intervals,shielding net structure,grounding pole setting interval and grounding resistance on the AC interference protection effect are analyzed through simulation calculations.Morever,for the typical case of alternating current interference in buried pipelines by an AC electrified railway,the influence degree of AC interference is analyzed through field testing,simulation and imatation,combined with the AC interference protection standards of buried pipelines.And the pipeline AC ground protection design scheme is further optimized,which effectively reduces the influence of AC interference on the pipeline.