Critical state solution of a cable made of curved thin superconducting tapes

In this paper, we develop a method based on the critical state for calculating the current and field distributions and AC losses in a cable made of curved thin superconducting tapes. The method also includes the possibility of considering spatial variation of the critical current density, which may be the result of the manufacturing process. For example, rare-earth-based coated conductors are known to have a decrease in transport properties near the edges of the tape: this influences the way the current and field penetrate the sample and, consequently, the AC losses. We demonstrate that curved tapes arranged on a cylindrical former behave as an infinite horizontal stack of straight tapes, and we compare the AC losses in a variety of working conditions, both without and with the lateral dependence of the critical current density. This model and subsequent similar approaches can be of interest for various applications of coated conductors, including power cables and conductor-on-round-core cables. (paper)