直埋单芯电缆的载流量数值计算

Numerical Calculation of Ampacity of Buried Single-core Cable

针对直埋单芯电缆敷设环境的复杂性引起的其载流量的难确定性,基于有限元法计算直埋电缆温度场和载流量的基本原理及方法,确定直埋电缆结构、敷设环境、材料等参数,应用热力学知识使用ANSYS软件工具对直埋单芯电缆温度场仿真,得到了电缆温度场的分布云图。在此基础上运用最小二乘法曲线拟合了温度场与载流量函数关系曲线,求得了电缆在确定环境下的载流量值。采用上述方法获得的数值计算结果与IEC60287解析计算结果相比较更加准确。

Because of the complexity of buried cable laying environment, as well as the hard certainty of carrying ca- pacity, this paper proposes the basic principles and methods of finite element calculation of power cable ampacity. Combined with thermodynamics and utilized ANSYS software to simulate the cable temperature field, the distributions of cable temperature are obtained. Used least squares curve to fit the temperature field and ampacity function relation curve, ampacity value of the cable in certain environment is acquired. Finally, the finite element calculation results, comparied with the IEC60287 analytic calculation results, are proved to be more accurate.