Design Method of SMES Magnet Considering Inhomogeneous Superconducting Properties of YBCO Tapes

Design of SMES magnet is a complicated process containing many problems such as stability, magnet configurations, and nonlinear characteristic during optimization. In this paper, we first studied the characteristics of considered YBCO tape such as B-J characteristics and inhomogeneous superconducting properties through a series of experiments. To select the best configuration that needs the least YBCO tape, we proposed a new stepped shape configuration of SMES magnet and compared the design of different stepped shape with rectangular cross-section magnet models. The results showed the inner stepped shape and outer stepped shape cross-section models need the least YBCO tape at 20 K and 77 K, respectively. Simulated annealing (SA) is adopted as optimization algorithm to avoid local optimal solution and find global optimal solution. Finally, we optimized a magnet prototype as an example considering all the obtained results in this paper.