A Gourd-Shape HTS Plate-Loop with Flux Density Amplification Function

High-temperature superconducting (HTS) magnets have huge advantages for providing strong magnetic fields within a compact structure and saving energy. However, it is almost impossible for them to operate in persistent current mode (PCM) since the soldering technique without resistance is unavailable. A gourd-shape HTS plate-loop configured by partial central cutting REBCO HTS tape with a function of flux density amplification is proposed. It consists of two circular holes with different diameters connected by a single slit. The conventional copper coil with an iron core is positioned within the big loop. This arrangement allows for a higher flux density in the small loop compared to the big loop by the field cooling (FC) exciting method, which can be seen as a form of flux density amplification. Flux density amplifying function of the gourd-shape HTS loop is confirmed by performing experiments and numerical simulation in 77 K. The results suggest that the gourd-shape HTS loop design offers significant advantages. It can provide higher magnetic field strength than the big loop, operate in PCM without current leads, and have a wider operational temperature range than LTS magnets. These attributes make it highly promising for various applications, such as magnetic resonance imaging (MRI), accelerator technology, and other fields that require high magnetic fields. Additionally, this design has the potential to lower manufacturing costs and facilitate easier implementation of HTS permanent magnets, thus promoting the widespread utilization of HTS technology in the industrial sector.