Performance investigation and improvement of superconducting energy storage coil

This paper introduces strategies to increase the volume energy density of the superconducting energy storage coil. The difference between the BH and AJ methods is analyzed theoretically, and the feasibility of these two methods is obtained by simulation comparison. In order to improve the volume energy storage density, the rectangular cross-section electromagnetic coil is optimized in terms of structure. The critical current, volume energy density, and loss of the four structures are compared. It is concluded that the three stepped cross-section coil has a significant impact on improving the volume energy storage density. According to the distribution of flux density up and down the magnet and the influence of the charging rate, a new step current injection method is proposed to improve the energy storage density further. The method proposed in this paper provides a guidance for the design of high-energy storage density magnets.