Study on the AC loss characteristics of the square cable-7 superconducting cable models

Superconducting cables, as a new type of power transmission conductor, have been highly valued by various countries in recent decades by virtue of the advantages of low loss, high efficiency, high current-carrying and space-saving power transmission. However, in the process of superconducting cables for transporting electricity, AC loss is a non-negligible problem. Compared with conventional 4 mm YBCO strips, square wires have better magnetic field distribution, which can reduce the vertical magnetic field and optimize the AC loss of high-temperature superconducting cables through multilayer structure. In this paper, square wire- 7 superconducting cables made of three new superconducting square wires are studied and the loss characteristics of the three cable models are investigated and analyzed, will use COMSOL finite element simulation and combined with the H-equation for simulation experiments, the experimental process. Firstly, we constructed a simulation model of the 2S-7 cable, the 4S-7 cable and the 6S-7 cable, and analyzed the three models of the magnetization loss and the AC losses, and also the cable structure with the best effect is analyzed comparatively. The results show that the square wire-7 cable model composed of 2S wire, 4S wire 6S wire has a certain structure dependence in loss characteristics. Considering the loss deterioration of the cable, the 4S-7 cable has a weaker deterioration effect on the AC loss while improving the current-carrying capacity and the magnetization loss, and the requirements for the wire and cable structure complexity are relatively low.