Scaling law of fringe fields as functions of stored energy and maximum magnetic field for SMES configurations

摘要

Although a SMES (superconducting magnetic energy storage system) has attractive potential for power management and quality control, the fringe field from the SMES restricts its site location. The fringe field outside a coil is expanded in a series of Legendre polynomials. The results are applied to the fringe fields of various SMES configurations, such as a single solenoid coil, toroidal coil, axially displaced coil. The derived fringe fields are scaled as functions of both the stored energy E and the maximum magnetic field Bm, which are the main parameters of superconducting coil design. The fringe fields decrease as E/Bm, (E(n+2)/Bm(2 n+1))13/, and ( E5/Bm7)13/, for a single solenoid, toroidal coil, and axially-displaced coil configurations, respectively, where n is the number of coils.