本文建立了单回路交叉互联接地方式的环流计算等值电路，通过数学分析推导出三相高压电缆金属护层上流过的环流和感应电压的大小。并指定了参数，在MATLAB中仿真计算出了护层环流。进一步由单回线路延伸到双回线路，建立了双回路环流计算的等值电路，考虑了两回路线芯电流和护层环流互相影响的因素，给出了双回路感应电压和护层环流的计算公式。在双回路情况下计算了三种不同情况下护层环流的大小，并探讨了三种不同因素对护层环流的影响。
First of all, the calculation equivalent circuit of the cross-interconnect grounding is established; through mathematical analysis, the circulation current and induced voltage through the metal sheath of the three-phase high voltage cable are deduced. And assign parameters calculate the circulation current of the sheath under MATLAB. Further from a single loop to a double loop, an equivalent circuit for the calculation of double loop circulation is established. In the case of double loop, considering the factors that affect the mutual influence of the core current and the sheath circulation current, the calculation formulae of the induced voltage and the circulation current of the sheath are given. The size of the sheath circulation current in three different cases was calcu-lated, and the influence of three different factors on the sheath circulation current was discussed.