几个单位联合进行了三轮近地电缆高空电磁脉冲耦合模拟试验.试验得到九芯电缆屏蔽层感应电流(皮电流)、芯线感应电压(芯电压)、芯线感应电流(芯电流)以及环境场之间的关系;分析了皮电流波形随外皮接地状态的变化,芯电压随负载电阻的变化;基于皮电流振荡频率与电磁波传播速度的关系,提出了屏蔽层-大地"传输线"等效相对介电常数概念,给出了等效相对介电常数随电缆高度变化的拟合式;皮电流计算与测量结果在波形、振荡周期、衰减规律等方面有较好的一致性.

HEMP coupling tests of the cable near ground were conducted. The relations of inducing skin current of shielding layer, core voltage and core current with the environment field were obtained. The change of shield layer current wave with grounding state of external shield and core voltage with loading resistance was analyzed. According to the dependence of shield layer current oscillating frequency on electromagnetic wave propagation velocity, conception of transporting line of shield layer-ground with equivalent relative dielectric constant was presented. fited equation of equivalent relative dielectric constant with change of cable height was given. There a good coincidence in the calculation of shield layer current and measuring results in the aspect of waveform, oscillating circle and attenuation law.