Conceptual Densign of 3-T All HTS MRI using No-Insulation Winding Technology: Electromagnetic Stress Reinforcement Structure

During the achievement of high-performance and miniaturization of magnetic resonance imaging (MRI) scanner, extremely strict indexes on magnet field, stability, and structural strength have been required. To address these problems, we applied “No-Insulation (NI) winding technology” in the magnet of 3-T all HTS MRI. However, in the process of miniaturization, electromagnetic stress becomes a technical challenge. In this study, we focus on designing a reinforcement structure for the magnet of 3-T MRI against electromagnetic stress. First, the magnetic field and electromagnetic force were calculated, and the distribution of electromagnetic stress and strain inside the winding of the designed magnet applied in 3-T MRI were analyzed, based on a finite element method. Moreover, the influence of the mechanical strength of the reinforcement materials used in the pads between sub-coils, shells and blind flanges in the magnet on the effect of stress characteristics, were evaluated respectively to clarify the optimized material and its consumption to establish the reinforcement structure of the magnet employed in 3-T MRI. Further, the influence of boundary condition on the stress characteristic of the NI HTS magnet was also evaluated. Finally, a feasible scheme of a stress reinforcement structure and its manufacture method were summarized for the NI HTS magnet applied in 3-T MRI.