Efficient Numerical Modeling of the Magnetization Loss on a Helically Wound Superconducting Tape in a Ramped Magnetic Field

Abstract

We investigate theoretically the dependence of magnetization loss of a helically wound superconducting tape on the round core radius $R$ and the helical conductor pitch in a ramped magnetic field. Using the thin-sheet approximation, we identify the two-dimensional equation that describes Faraday's law of induction on a helical tape surface in the steady state. Based on the obtained basic equation, we simulate numerically the current streamlines and the power loss $P$ per unit tape length on a helical tape. For $R\gtrsim w_0$ (where $w_0$ is the tape width), the simulated value of $P$ saturates close to the loss power $\sim (2/\pi )P_{\mathrm{flat}}$ (where $P_{\mathrm{flat}}$ is the loss power of a flat tape) for a loosely twisted tape. This is verified quantitatively by evaluating power loss analytically in the thin-filament limit of $w_0/R\to 0$. For $R\lesssim w_0$, upon thinning the round core, the helically wound tape behaves more like a cylindrical superconductor as verified by the formula in the cylinder limit of $w_0/R\to 2\pi$, and $P$ decreases further from the value for a loosely twisted tape, reaching $\sim (2/\pi {)}^2{P}_{\mathrm{flat}}$.

7 pages, 8 figures, 1 table

Cited by in corpus (1)

• Round-Core-Radius-Dependent Electromagnetic Coupling of Multifilament Helical Superconducting Tapes in a Swept Magnetic Field