Optimal design method for MRI superconducting magnets with ferromagnetic shield

Author

Noguchi, S. ; Ishiyama, A.

Author_Institution

Dept. of Electr. Eng., Waseda Univ., Tokyo, Japan

Volume

33

Issue

2

fYear

1997

fDate

3/1/1997 12:00:00 AM

Firstpage

1904

Lastpage

1907

Abstract

This paper describes an optimal design method for highly homogeneous superconducting magnet systems with a ferromagnetic shield. The presented design technique is a combination of the equivalent magnetization current method for the computation of the magnetic field problem, which includes nonlinear and saturated iron, and simulated annealing for solving the corresponding optimization problem. The equivalent magnetization current method is superior in estimating the field homogeneity of the center of the magnet systems. By using simulated annealing, the positions of each solenoid coil are optimized as continuous design variables, while the number of turns and layers of the coil windings are treated as discrete design variables. The details of the algorithm and some examples of its application to 1.5-tesla magnet systems with three types of magnetic shielding are shown

Keywords

biomedical NMR; biomedical equipment; design engineering; ferromagnetic materials; magnetic fields; magnetic shielding; simulated annealing; superconducting magnets; windings; MRI superconducting magnets; algorithm; coil windings; continuous design variables; discrete design variables; equivalent magnetization current method; ferromagnetic shield; field homogeneity; magnetic field problem; magnetic shielding; nonlinear Fe; optimal design method; saturated Fe; simulated annealing; solenoid coil; Coils; Computational modeling; Design methodology; Design optimization; Iron; Magnetic resonance imaging; Magnetic shielding; Saturation magnetization; Simulated annealing; Superconducting magnets;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.582660

Filename

582660