Design Method of Cylindrical Self-Shielding Coils in Spindle-Shaped Magnetic Shielding Cylinders Eliminating Ferromagnetic Boundary Coupling
Xueping Xu, Yi Liu, Chunbo Han, Xin Sun
Abstract
The uniformity of the coils is often compromised by the coupling between ferromagnetic materials and coils. The spindle-shaped magnetic shielding cylinder (sMSC) has additional benefits over the MSC. A single-layer cylindrical self-shielding coil designed by the improved target field method (TFM) that is available inside sMSC is proposed. The method dynamically regulates the internal uniformity and external self-shielding performance by assigning different weights to the internal and external field points. To reduce the dependence of the traditional TFM design on relevant factors, the hunter-prey optimization (HPO) is applied to optimize it. The modeling and experimental findings reveal that the maximum homogeneity deviations of the self-shielding coil are 0.24% and 0.28%, respectively. The self-shielded coil takes up less space in comparison to the normal non-moment Helmholtz coils. This method ensures the uniform performance of the internal magnetic field (MF) while rapidly attenuating the external MF.