Fabrication and test of superconducting generator with ring windings

Application of superconductivity to electric machines can bring about wider alternatives to the fundamental configuration comparing with the conventio nal counterparts. As well known, multi-phase electric machine can be easily realized with ring-winding configuration. Because multi-phase machine is e ffective to generate smooth DC voltage with very low ripples, it would be a ttractive for HVDC power transmission system. Besides, the ring-winding con figuration is suitable for high-voltage design. Armature windings do not cr oss each other as in the conventional windings The authors fabricated small experimental superconducting generator with superconducting ring-winding t ype armature. The armature is composed of 15 coils, that is, the number of phases is 15. It has also superconducting field winding. The machine does n ot have iron core except for the outer magnetic shield made of laminated ir on. A preliminary test was carried out. The output power is rectified by 15 sets of diode bridges. The voltage, current, and output power are presente d. Also, the design and construction aspects; of the machine are presented.