Design of a High-Homogeneity 55 T Pulsed Magnet for High-Resolution Nuclear Magnetic Resonance Measurements

We present the design of a high-homogeneity 55 T pulsed magnet for high-resolution nuclear magnetic resonance (NMR) measurements. The magnetic field spatial distributions of a conventionally designed pulsed magnet with an ideal axisymmetric model and a practical asymmetric spiral model were investigated. The study also explored the impacts of the eddy current, thermal effect, and deformation by electromagnetic force, which result in changes to the magnetic field spatial distribution in the magnet. Based on the analyzed magnetic field profiles of the conventional pulsed magnet, an optimized solution was proposed using the split structure in the two continuous conductor layers to reduce the average current density near the middle plane and achieve high magnetic field homogeneity of the pulsed magnet. The results of the design show that by implementing an ideally transitioned split, it is possible to achieve a high-homogeneity pulsed magnet within a cylindrical region with a diameter of 1 cm and a height of 1 cm, where the peak-to-peak field inhomogeneity is less than 100 ppm.