Design Method of a High Field HTS Magnet Consisting of Pancake Windings Having Different Current in Each Pancake Winding

HTS pancake windings have been commonly used for the insert coil of high field magnets. All pancake windings have been connected in series and excited by a single power source. In that case, currents of the whole pancake windings were limited by the minimum current of the top and the bottom pancake windings where maximum perpendicular magnetic field was applied. This paper proposed the multiple power excitation of the HTS magnet which consists of pancake windings. It was able to increase the magnetic field of the magnet by conducting critical currents to all pancake windings. Results of calculation by using a model BSCCO magnet shows that proposed method was able to generate higher magnetic field comparing with the conventional single power excitation.