Theory and Simulation of Thermal Field of AC Cable

At present, the power supply reliability of high-voltage cable lines is a technical hotspot and difficulty that is closely watched in the world. The effect of cable thermal field is an important factor causing defects and failures, so a comprehensive analysis of it is an important part of monitoring and diagnosis. In this paper, the cable thermal field is firstly modeled through theoretical analysis. Secondly, the calculation theory and influencing factors of cable ampacity are analyzed, and then its calculation formulas under various working conditions are given. Finally, a simulation model is established to verify the theory. The non-contact online diagnosis of cable core temperature is realized, which is helpful for early detection of early hidden dangers of cables and comprehensively improves the power supply reliability of the power grid.