Numerical Study of Encapsulated Joint Performance in Soldered-Stacked HTS Wires

Combining several high temperature superconducting (HTS) tapes into an assembled HTS conductor can enhance the current-carrying capacity, mechanical strength and improve the large width-to-thickness ratio of HTS tapes. And in practical applications, joints can extend the assembled HTS conductors to required lengths. Therefore, encapsulated joints for Soldered-stacked (SS) wire has been proposed as a preliminary study to achieve long length Soldered-Stacked-Square (3S) wire. And in this paper, we numerically study the performances of different types of encapsulated joints. Firstly, encapsulated joints are divided into two categories according to their positions, and a nonlinear circuit model is presented to demonstrate the numerical study process and experiments are conducted to determine the parameters in this model. Then, resistance performances of the encapsulated joints are discussed such as the “multilinear resistance” phenomenon where the encapsulated joints show different resistance under different current. And HTS tape arrangements in the encapsulated joint are also discussed to achieve minimum resistances.