Article

Magnetic field calculations including the impact of persistent currents in superconducting filaments

CERN, Geneva
IEEE Transactions on Magnetics (Impact Factor: 1.42). 04/2002; DOI: 10.1109/20.996213
Source: IEEE Xplore

ABSTRACT The magnetic field in the coils of superconducting magnets induces
so-called persistent currents in the filaments. Persistent currents are
bipolar screening currents that do not decay due to the lack of
resistivity. The NbTi-filaments are type II superconductors and can be
described by the critical state model. This paper presents an analytical
hysteresis model of the filament magnetization due to persistent
currents which takes into account the changing magnetic induction inside
the filament. This model is combined with numerical field computation
methods, taking local saturation effects in the ferromagnetic yoke into
consideration

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