Investigation of Thermal Modeling for Underground Cable Ampacity under Different Conditions of Distances and Depths

Abstract

Underground cables are affected by a many different factors, including the temperature distribution surrounding the cable, the depth of the cable, distances between the cables, 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, (0.2 and 0.4 (meters)) distances between the cables, 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 useful for reducing conductor temperature and securing a specific cost metric while being of exceptional importance to take full advantage of cable ampacity. © 2021 IEEE.