高压直流输电接地极对埋地油气管道干扰规律研究

Interference Law of Grounding Electrode of HVDC Transmission to Buried Oil and Gas Pipeline

针对高压直流(HVDC)输电接地极对埋地油气金属管道产生感应电压,造成管体腐蚀及气液联动开关误动作的问题,利用ANSYS建立金属管道感应电位耦合仿真模型,分析了接地极到管道距离、土壤电阻率、防腐层电阻3个因素对管道干扰的影响,并自主研制了HVDC对金属管道感应电位在线状态监测系统。仿真和实验结果表明:土壤电阻率的增加使得干扰电位呈线性增大,干扰电位随管道防腐层电阻增大而呈指数增加,接地极与管道距离变大,干扰电位呈指数降低。系统的数据采集模块达到了对信号的测定兼具稳定性且高准确度的要求,通过实验进一步验证了仿真中得到的干扰规律。

In view of the induced voltage of buried oil and gas metal pipeline generated by the grounding electrode of high voltage direct current(HVDC)transmission,which resulting in pipe corrosion and isoperation of gas-liquid linkage switch,the coupling simulation model of induced potential of metal pipeline is established by using ANSYS.The influences of three factors on pipeline interference,such as distance from grounding electrode to pipeline,oil resistivity and anti-corrosion coating resistance are analyzed and the on-line condition monitoring system of induced potential of HVDC to metal pipeline is independently developed.The simulation and experimental results show that the increase of soil resistivity makes the interference potential increase linearly the interference potential increases exponentially with the increase of pipeline anti-corrosion coating resistance,the distance between grounding electrode and pipeline increases and the interference potential decreases exponentially.The data acquisition module of the system meets the requirements of both stability and high accuracy.The interference law obtained in the simulation is further verified by experiments.