Analysis of Overloading and Its Impact on the Lifetime of XLPE-Insulated Power Cables

This study presents an overloading analysis of medium voltage underground power cables using MATLAB simulations, focusing on maintaining insulation integrity. The analysis is based on the critical overloading temperature, which serves as a threshold to prevent immediate insulation failure. However, even when the cable operates within this thermal limit, repeated or prolonged overloading can contribute to cumulative thermal aging, leading to a gradual reduction in the cable’s expected service life. Thermal stress accelerates insulation degradation, increasing the risk of premature failure over time. The results reveal that a 25% overload for 3 hours can result in ~13% life loss, while 50% overload for 6 hours can lead to nearly 48% insulation degradation. The findings emphasize the importance of managing cable loading conditions to ensure safe operation and extended service life. Implementing preventive measures, such as monitoring temperature profiles and optimizing load distribution, can help minimize lifetime reduction while ensuring safe power transmission.