短时大电流入地时管道阻性耦合电压计算方法研究

交流架空输电线路与钢制埋地管道共用走廊资源的现象越发频繁,短时大电流入地时产生的阻性耦合电压将会严重加速管道腐蚀。为量化计算埋地管道阻性耦合电压,文中提出一种基于CDEGS仿真模型的计算方法。首先建立大电流入地仿真模型;其次给出工频电流接地时管道阻性耦合电压的计算方法,并分析电流幅值、土壤电阻率以及电流入地点离管道最近点的距离对管道阻性耦合电压的影响;最后给出雷电流入地时,计及频率的管道阻性耦合电压的计算方法以及基于时频转换的电压最大值计算方法,并分析雷电流幅值、雷电流入地点离管道最近点的距离、土壤电阻率以及雷电流经多杆塔入地对管道阻性耦合电压的影响。

Calculation method of resistive coupling voltage of buried steel pipelines in short-term high current

The phenomenon of sharing corridor resources between AC overhead transmission lines and buried steel pipelines is becoming more and more frequent, and the resistance coupling voltage generated by short-term high current of lines will seriously accelerate the corrosion of pipelines. In order to quantitatively calculate the resistive coupling voltage of buried pipeline, a calculation method based on CDEGS simulation model is proposed in this paper. Firstly, the simulation model of large current entering the ground is established. Secondly, the calculation method of resistive coupling voltage of pipeline when power frequency current grounding is given, and the influence of current amplitude, soil resistivity and the distance between the nearest point of current entering and the pipeline on the resistance coupling voltage is analyzed. Finally, the calculation method of resistive coupling voltage taking into account frequency and time-frequency conversion are given when lightning flows into the ground. The calculation method of maximum exchange voltage is given, and the influence of lightning current amplitude, distance from the nearest point of the pipeline, soil resistivity and of lighting flow into ground through multiple towers on the resistance coupling voltage is analyzed.