基于BLT方程的埋地管道电磁脉冲响应规律研究

高空核爆电磁脉冲(HEMP)会在埋地油气管道上产生感应电流和感应电压,可能对油气管道的测量监控装置及阴极保护系统产生影响。为研究HEMP对埋地金属管道的电磁影响,本文利用合成电压波的思想推导了可用于分析不均匀传输线响应的BLT超矩阵方程,通过与链参数方法的计算结果进行比较,验证了该方法的正确性和有效性。建立了埋地管道的分段串联传输线模型,应用BLT超矩阵方程计算了管道特性阻抗连续时管道参数和管道折角对管道上电流、电压的影响,将入射仰角、入射方位角和场源方位角作为随机变量,计算了入射波状态对响应电流影响的统计信息；针对大地电导率横向差异引起的特性阻抗不连续情况,计算分析了管道电流电压的响应情况；研究结果可为油气管道的电磁脉冲防护提供相关参考。

Research of Electromagnetic Pulse Response of Buried Pipeline Based on BLT Equation

High-altitude electromagnetic pulse (HEMP) can cause current and voltage on the buried oil/gas pipelines, which may has adverse effects on the normal operation of monitoring instrumentation and cathodic protection system. In this paper, in order to study the electromagnetic effects of HEMP on buried metal pipelines, the BLT super-matrix equation for response calculation of non-uniform transmission line was deduced based on the theory of the composite voltage wave. By comparing the calculation results with those of the chain parameters method, the correctness and validity of this method are verified. The segmentation transmission line model of the pipeline was established, the influences of pipeline parameters and turning angles on the current and voltage were studied by using the BLT super-matrix equation, taking elevation angle, azimuth angle and field source azimuth angle as a set of random variable, the statistical effect of angles on induced currents in the pipeline terminals was calculated. Considering the discontinuity of pipeline characteristic impedance caused by the lateral variation of earth conductivity, the current and voltage response of the pipeline was calculated. The research results can provide relevant reference for the electromagnetic protection of oil/gas pipelines.