Determination of the current carrying capacity of cables using the finite element method

Abstract Finite element network is composed to determine the temperature rise within and around a three phase 110 kV underground cable bunch that makes it possible to analyze both the transient and the steady-state load conditions for cyclic daily load diagrams. The cable trench profile, bedding made of special mixtures, concrete and asphalt cover and soil and ground surface heat conductance effects are considered including the soil drying out phenomenon. An iterative procedure is suggested for determining the maximum allowable peak load for typical hourly cable load diagrams. The proposed approach was applied to assess the maximum ampacity of a 110 kV cable laid in Belgrade urban area as well as to quantify the favorable effects of the bedding mixture.