影响直埋电缆温度分布主要因素的模拟研究

Simulation study on main factors affecting temperature distribution of buried cables

目的:散热是影响直埋电缆安全经济运行的难题,而理清影响直埋电缆温度场分布的主要因素是解决该问题的重要前提。方法:采用有限元法,建立直埋电缆稳态温度场的传热模型,并通过正交设计方法,探讨了土壤导热系数、土壤温度、环境温度和电缆间距等因素的影响。结果:以400 kV的XLPE高压电缆为例,确定了不同因素对电缆温度场分布的影响,结果发现:土壤导热系数对直埋电缆温度场的影响最为显著,其次是环境温度和电缆间距,而土壤温度的影响最小。结论:在直埋电缆敷设工程中,有必要建立填埋土壤的热物性数据库,以高导热系数的回填材料为配合体,提高其散热能力,从而保障电缆安全经济运行。

Aims:Heat dissipation is a difficult problem that affects the safe and economic operation of directly buried cables.This paper analyses mainly influence factors of temperature distribution of directly buried cables.Methods:By using the finite element method,the heat transfer model of steady-state temperature fields of directly buried cables was established.The influence of soil thermal conductivity,soil temperature,environmental temperature and cable spacing was discussed by the orthogonal design method.Results:Taking the 400 kV XLPE high-voltage cable as an example,the influence of different factors on the temperature field distribution of the cable was determined.The results showed that the soil thermal conductivity had the most significant influence on the temperature field of the directly buried cable,followed by the environmental temperature and cable spacing.The soil temperature had the least influence.Conclusions:In the direct buried cable laying project,it is necessary to establish the thermophysical property database of the landfill soil.The backfill material with high thermal conductivity should be used to improve its heat dissipation capacity and ensure the safe and economic operation of the cable.