Study on a cross section of high temperature superconducting coil

The fitting equations of critical current and n value were derived from measured data of Ag-sheathed Bi-2223 tapes concerning the magnetic fields and flux angles at 77 K. The critical current of a high temperature superconducting coil can be calculated with these equations together with a magnetic field analysis of a coil. Critical current, magnetic field, flux How loss, stored energy, etc. were calculated for HTS coils with various coil aspect ratios along the curve, where Fabry Factor F of 1.97 was kept constant. It was made clear that the central magnetic field per coil volume is maximum at the coil aspect ratio providing the minimum coil volume.