The aim of this paper is to calculate the temperature distribution of a cable conductor and the soil surrounding the cable under cyclic loading conditions, taking into account the formation of a drying zone in the backfill material. The thermal model of an underground cable is considered by using the IEC 60853-2 method, including the effects of the variations in temperature on the thermal resistivity and specific heat of the soil. The results are compared with IEC 60853-2 and thermoelectric equivalent method calculations. This study is done on eight sandy soil types as backfill materials, and calculations are carried out by using a 33-kVx cable. The results indicate that the modifications done on the IEC 60853-2 method are required to improve its capability to simulate the field conditions during load cycling of power cables.
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