中文摘要：

根据电流场和静电场理论，分析了在计算电缆绝缘层电场分布时必须同时考虑电导率和空间电荷的影响。为计算直流交联聚乙烯（XLPE）电缆绝缘层径向电场及温度场分布，应用多物理场有限元仿真软件COMSOL模拟实际运行工况，解决了电热耦合场场量的计算。仿真计算时，电导率模型采用的是最适合XLPE绝缘材料的经验公式；设计阶段的空间电荷数据是采用电声脉冲（PEA）技术测量绝缘样品而得到。仿真计算结果表明，设计的30kV直流XLPE电缆是满足设计和实际运行要求的。

英文摘要：

In terms of current field and electrostatic field, the necessity of considering both conductivity and space charge in calculation of electric field in cable insulation was analyzed. In order to calculate the distribution of radical electric field and temperature field in insulation of DC XLPE cable, the multi-physics FEM software COMSOL was used to simulate the electro-thermal coupled field at the actual case. Empirical formula which was perfect for XLPE insulation as model of conductivity was adopted in calculation. Under design phase, space charge data was derived from measurement on insulation samples using the pulsed electro acoustic （PEA） technique. The result of simulation showed the designed 30 kV XLPE DC cable could fulfill the demand of design and actual operation case.