Numerical Electromagnetic Simulation of Effective Partial-insulation NbTi Superconducting Coil

The no-insulation winding technique is a promising way of enhancing the thermal stability of NbTi superconducting coils. However, it takes a long time to charge a no-insulation superconducting coil, because the time constant is relatively large. Hence, a partial-insulation winding technique was also proposed to reduce the time constant with a high thermal stability. However, the time constant of the previously proposed partial-insulation NbTi superconducting coil could not drastically be improved, and the cause was investigated using a partial-element equivalent circuit model. Therefore, in this paper, we propose a new partial-insulation structure, and the effectiveness is verified using a partial element equivalent circuit model. The results show that a relatively small time constant is achieved when charging and discharging the proposed partial-insulation NbTi superconducting coil.