管道强制电流阴极保护电位计算的等效电阻法

针对受一个阴极保护站保护的埋地钢质管道,提出了管道电位和电流计算的等效电阻方法,并用解析方法推导出管道覆盖层破损后电位和电流的计算公式。等效电阻方法将所研究管道划分成若干管段,用一个电阻表示管段对轴向电流的阻碍作用,一个电阻表示对径向电流的阻碍作用,从而将管道强制电流阴极保护系统表示成一个等效电阻电路。利用网孔电流法求解该电路的网孔电流,并计算出管道各节点上的电位。计算结果表明,等效电阻方法得到的结果与解析法的计算结果完全吻合。该方法特别适合于管径和（或）过渡电阻发生变化的情况。

Equivalent Resistance Method for Calculating Potential of Impressed Current Cathode Protection System for Pipeline

Equivalent resistance method is brought forward to calculate the potential and the current of a buried steel pipeline protected by a cathode protection station.Analytic method is used to deduce pipeline potential and current formula after the damage of external coating.By means of equivalent resistance method,the pipeline can be divided into some segments,and the resistance of each segment to axial current and radial current can be described by one electrical resistance respectively,thus an impressed current cathode protection system is expressed as an equivalent resistance electric circuit. Mesh-current method is used to solve the mesh current of this circuit, and potential of each pipeline node are figured out. The computing results show that the results based on equivalent resistance method agree with the ones based on analytic method. The method is especially suitable for pipelines with variational diameter and/or variational transition resistance.