Theoretical evaluation of the screening-current-induced magnetic field in superconducting coils with tape wires

Abstract

We theoretically investigate the physical mechanism of the screening-current-induced field (SCIF) in solenoid coils wound with superconducting tape wires. We derive the direct relationship between the SCIF and the magnetization of tape wires, and a scaling law for the SCIF and the coil dimensions is demonstrated. A simple analytical expression of the SCIF is obtained as functions of current load factor, tape wire width, and the coil dimensions. We verify that the published data for the precise numerical computation of SCIF are roughly fitted by our theoretical results for flat coils where the height is smaller than the outer diameter.

A prediction method for the screening current induced field in HTS magnets based on time series models

“…The first advantage of theoretical calculation is its speed, which directly computes the SCIF values from the magnet parameters. The relationship between SCIF and the magnetization of HTS tapes was derived in [18,19], and theoretical functions were proposed to evaluate SCIF. Although the theoretical results can be roughly consistent with accurate simulations, there are limitations due to the variable magnet structures and the complex physical mechanism of screening current.…”