Simulation Study on Influence of Cable Tunnel Shape on Temperature Rise of XLPE Cable

The operating temperature of the cable has a great influence on the service life of the cable. The laying mode of the cable channel has an influence on the temperature rise of the cable. This paper studies the temperature rises characteristics of 110 kV XLPE cable under different channel laying conditions. The results show that under 200 A load current, the maximum temperature of cables in a single-track tunnel, parallel tunnel, pipe jacking, and parallel pipe jacking are 323.6 K, 323.75 K, 321.11 K, and 321.18 K respectively. It can be seen from the results that among the four cable-laying methods studied in this paper, the maximum temperature of the cable in the parallel tunnel is higher than that in a single-track tunnel, and the maximum temperature of the cable in parallel pipe jacking is slightly higher than that in pipe jacking. The influence of the number of cable groups on the cable temperature rise is compared. It is pointed out that there is a temperature cycle between tunnels in parallel tunnels, and the maximum temperature rise of a single cable group is slightly lower than that of a single-track tunnel. The difference between the maximum temperature rise of the three-circuit cable group and the maximum temperature rise of the four-circuit cable group is small. Both of them can be used as cable group laying methods for the efficient use of cable channel space. The research content of this paper can provide a basis for the selection of appropriate cable channel laying and cable group number distribution for the cables newly put into the power grid, prolong the service life of cables, reduce the times of cable replacement in the channel, and improve the utilization rate of cable resources.