Temperature Distribution in a 245 kV AC XLPE Cable

The lifetime of power cable systems strongly depends on temperature. Above 90°C morphological and chemical changes occur in the structure of the dielectric materials, and may greatly reduce the cable service life. Therefore, an accurate determination of temperature distribution is important in evaluating the cable performances during operating conditions. In this work, temperature distribution in a 245 kV AC XLPE cable newly manufactured by an Algerian company (CABEL) is carried out. The influence of the ambient temperature and the effect of the load current variations on the temperature distribution of the cable are also investigated. Based on the conditions that have been assumed in the model, the newly manufactured cable can operate under 1342 A without risks of deterioration or damage. However, when the surrounding temperature exceeds 313 K (40°C), the permissible temperature limit on the conductor is exceeded with concomitant risk of overheating of the cable. In hot regions of the world (like southern Algeria) the current carrying capacity should be reduced to avoid premature deterioration of the cable. The simulation results reveal also that the higher the loading current is, the higher the cable temperature is and the largest temperature increase takes place in the cable core.