Design of Superconducting Shim Coils for a 400 MHz NMR Using Nonlinear Optimization Algorithm

Author

Zhipeng Ni ; Lankai Li ; Geli Hu ; Cong Wen ; Xinning Hu ; Feng Liu ; Qiuliang Wang

Author_Institution

Key Lab. of Appl. Supercond., Inst. of Electr. Eng., Beijing, China

Volume

22

Issue

3

fYear

2012

fDate

6/1/2012 12:00:00 AM

Firstpage

4900505

Lastpage

4900505

Abstract

A set of superconducting shim coils for a 400 MHz nuclear magnetic resonance spectrometer was designed, analyzed and constructed. A nonlinear optimization algorithm was employed for the calculation of the optimal conductor shapes and positions of superconducting shim coils. In the optimization, a number of system parameters, including field errors, axial size of coils and spherical harmonics have been constrained to acceptable levels. The results have the property of combining best field quality and also controlling the desired harmonics terms strength. The proposed methodology can also be used to design superconducting and resistive shim coils for other homogeneous magnet systems.

Keywords

NMR spectrometers; optimisation; superconducting coils; superconducting magnets; NMR; field errors; frequency 400 MHz; homogeneous magnet systems; nonlinear optimization algorithm; nuclear magnetic resonance spectrometer; resistive shim coils; spherical harmonics; superconducting shim coils; Harmonic analysis; Magnetic fields; Nuclear magnetic resonance; Optimization; Superconducting coils; Superconducting magnets; NMR; nonlinear optimization algorithm; sensitivity; spherical harmonic; superconducting shimming;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/TASC.2011.2176699

Filename

6084722