Speaker
Description
Korea Medical Device Development Fund (KMDF) launched a national project to develop a high-temperature superconductor magnet for magnetic resonance imaging (MRI) in 2020. This project's ultimate target is to develop a 6 T 320 mm high temperature superconductor (HTS) magnet. Major concerns in developing the MRI magnet in terms of electromagnetic dynamics are the time-varying field uniformity due to screening current-induced field (SCF) and turn-to-turn leak current relaxation and the consequent temporal field instability in a target diameter spherical volume (DSV) space. Unfortunately, few studies have been conducted to investigate real-time SCF relaxation and the consequent spatial and temporal magnetic field variation with a real-time monitoring approach. Thus, this paper provides real-time monitoring results using a Hall sensor array to investigate the spatial and temporal magnetic field variation induced by SCF in a no-insulation (NI) HTS test coil. Design, fabrication, and operation of an NI HTS test coil were performed. A Hall sensor array was attached to the test coil surface to measure the axial magnetic field's temporal variation and the consequent harmonic coefficient. Calculation with a finite element method (FEM) based simulation model is conducted to compare results with measurements. We provide discussions that include comparison results between calculation and measurement.
This work was supported by the Korea Medical Device Development Fund grant funded by the Korea government (the Ministry of Science and ICT, the Ministry of Trade, Industry and Energy, the Ministry of Health & Welfare, the Ministry of Food and Drug Safety) (Project Number: 202011C21)
