在粒子模拟的基础上，结合经典空间电荷限制流、磁绝缘临界电流的理论公式，拟合得到磁绝缘传输线中空间电荷限制流的修正计算公式，并进一步建立磁绝缘传输线损失电流的插值计算模型。该模型不需要求解广义泊松方程，计算效率高。通过对长同轴磁绝缘传输线的等效电路模拟，得到了与全尺寸粒子模拟结果基本一致的负载电压波形，插值计算模型不仅正确地反映了磁绝缘传输线中的电流损失过程,而且其等效电路模拟计算效率比粒子模拟提高3000倍以上。

A modified formula for space-charge-limited(SCL) current was established, based on particle-in-cell(PIC) simulation results and formulas for conventional SCL current and critical magnetic insulation current. And a fast interpolation model for loss current in magnetically insulated transmission line(MITL) was presented, which refrains from solving generalized Poisson equation and can be used in equivalent circuit modeling. As verification, a long coaxial MITL was simulated with both the equivalent circuit method and the PIC method. It was found that the time histories of the load voltage agreed well with each other, which were obtained by the two methods separately. The interpolation model repeated the dynamic process of current loss and the computation efficiency of the equivalent circuit simulation was more than 3000 times higher than that of the PIC simulation.