Thermal Modeling for Underground Cable Under the Effect of Thermal Resistivity and Burial Depth Using Finite Element Method

Abstract

Many factors affect underground cables, including the temperature distribution surrounding the cable, the depth of the cable, the thermal resistivity of the soil, and the material the cable is backfilled. The study and analysis of these factors are exploited as much as possible to carry the maximum possible current through the power transmission cable. Calculations were made for single power cables with a flat configuration at a burial depth (0.8 and 1) meters, (0.8 and 1) km/w soil resistivity, and two types of backfill materials: cement-sand mixture backfill (CSB) and thermal backfill for the Aluminum conductor. The proposed model can determine the temperature distribution in the soil, thermal backfill, and around cables. The results essentially show that appropriate thermal backfill and spatial geometric characteristics are not only useful for reducing conductor temperature, but also for securing a specific cost metric at the same time being of exceptional importance to take full advantage of cable ampacity.