Iterative EM Design of an MRI Magnet Using HTS Materials

• Published in: IEEE transactions on applied superconductivity Vol. 17; no. 2; pp. 2192 - 2195
• Main Authors: Minfeng Xu, Ogle, M., Xianrui Huang, Amm, K., Laskaris, E.T.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: New York, NY IEEE 01.06.2007; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Applied sciences; Design optimization; Electrical engineering. Electrical power engineering; Electromagnetic fields; Electromagnets; Electronic equipment and fabrication. Passive components, printed wiring boards, connectics; Electronics; Exact sciences and technology; High temperature superconductors; High-temperature superconductor (HTS); Magnetic fields; Magnetic materials; Magnetic properties; Magnetic resonance imaging; magnetic resonance imaging (MRI); Materials; Mathematical analysis; Optimization; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Studies; Superconducting devices; Superconducting filaments and wires; Superconducting films; superconducting magnet; Superconducting magnets; Superconducting materials; Superconducting tapes; Superconductivity; Superconductors; Various equipment and components; Wire; Electromagnetism; High-temperature superconductor (HTS); Magnet; Critical parameter; System design; Iterative method; Power supply; Power electronics; Nuclear magnetic resonance imaging; Optimal design; magnetic resonance imaging (MRI); Superconducting magnet; Superconducting tapes; Magnetic field; Comparative study; High temperature superconductor; Low temperature
• ISSN: 1051-8223; 1558-2515
• DOI: 10.1109/TASC.2007.898075

Conventional superconducting MRI magnet electromagnetic (EM) design involves the critical parameters of the magnet field and dimensional requirements, plus the low temperature superconductor (LTS) wire properties. When using HTS material for an MRI magnet, in addition to the conventional characteristics of a superconductor, the wire and the joint resistance need also to be considered. This is mainly due to the relatively low n-values of the BSCCO tape when compared to that of a conventional LTS wire, and it is also due to the more resistive joint nature for HTS joints. This paper discusses an iterative EM design procedure that calculates the resistance of the HTS wire/tape for the entire magnet, which is a strong function of the magnetic fields at different locations in the coils. The resistance is fed back to the regular MRI EM design for optimization, in order to meet resistance target and the ordinary MRI design goals. This iterative design process results in an optimized HTS MRI design with overall low resistance for magnet drifting and power supply requirements.