Conceptual Design and Sensitivity Analysis of MRI Magnets From REBCO HTS Tapes


Boran Y., Kara H., Inanir F., Yildiz S.

IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, vol.32, no.8, 2022 (Peer-Reviewed Journal) identifier

  • Publication Type: Article / Article
  • Volume: 32 Issue: 8
  • Publication Date: 2022
  • Doi Number: 10.1109/tasc.2022.3200575
  • Journal Name: IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY
  • Journal Indexes: Science Citation Index Expanded, Scopus, Academic Search Premier, PASCAL, Aerospace Database, Applied Science & Technology Source, Business Source Elite, Business Source Premier, Communication Abstracts, Compendex, Computer & Applied Sciences, INSPEC, Metadex, Civil Engineering Abstracts
  • Keywords: Magnetic resonance imaging, Superconducting magnets, Magnetic shielding, Magnetic noise, Magnetic fields, High-temperature superconductors, Magnetic flux, COMSOL, double pancake coil, high temperature superconductor, magnetic resonance imaging

Abstract

An actively shielded wide-bore magnet system has been designed for magnetic resonance imaging. The gradient-based optimization solver of COMSOL Multiphysics has been used to obtain an optimum geometrical arrangement of symmetrical electromagnets in the magnetic resonance imaging (MRI) system. To generate a high and homogeneous magnetic field, we employed a second-generation rare-earth barium-copper-oxide (REBCO) high-temperature superconductor (HTS), which was wound into 10 double pancake coils (DPC). The dimensions of the DPC sets have been chosen considering the size of REBCO HTS tapes, and the optimized design solution provides magnetic field, stray field, and current passing through the HTS tapes on each DPC set. The design details of a 1.5 T actively shielded magnet as well as the sensitivity analysis of the inhomogeneity, stray field, and currents with respect to coil positions have been presented. Optimum parameters for various designs are listed. The inhomogeneity of 1.23 ppm in the 200 mm diameter of spherical volume (DSV) and a stray field of as low as 0.05 G outside of the 5 m distance were achieved. Additionally, a low peak field of 2.40 T in DPC sets has been accomplished.