Volume Energy Density Improvement for HTS Coil Using Structure Optimization and Step Current Supply

This paper investigates strategies to improve the volume energy density of the solenoidal energy storage coil. The maximal radial magnetic field, critical current, volume energy density and tapes utilizing rate of three different step-shaped solenoidal coil are analyzed and compared. The double step-shaped structure of the coil is selected as the energy storage device to satisfy the requirement of the volume energy density. The volume energy density can be further improved if step current is supplied to the different step coil under the same shape and inductance.