Evelopment of a Highly-stable Superconductor with Controlled Current Distribution

作为前期的研究工作，我们研究了超导驾驶室中电流分布不均匀对稳定性的影响。当保持单股电缆之间的电流传递特性超过参考值时，即使在单股电缆之间产生不均匀电流，电流传递部分的外能也不会使稳定性恶化，对稳定性的影响很小。得到了上述研究成果，并对控制导体内电流分布的高稳定性导体进行了开发研究。对导体中的电流分布进行了控制，并对具有高稳定性和降低交流损耗的电缆结构的超导导体进行了开发研究。首先设计了导体中的电流分布和交流损耗的关系。从使用导管内电缆导体的大型超导线圈交流损耗的测量结果来看，交流损耗增大，认为这是阻碍大型超导线圈利用的新因素，并急于对其可能的原因进行调查。在本研究中，利用2根绞合电缆进行单元实验，是基于对绞合电缆导体中电流分布不均匀性随导体纵向变化的估计。结果表明，扭转湍流引起的电流分布的不均匀性是导致交流损耗增大的可能原因。其次，根据导体中电流分布对稳定性和交流损耗影响的研究结果，提出了一种新型结构超导导体的设计理念，使超导导体的稳定性和低交流损耗达到平衡。在此基础上进行了试制导线的设计，并对其交流损耗和稳定性进行了分析。此外，为了验证导体制造的可行性，还进行了导体试制。少

We have studied the effects of the ununiform current distribution in the superconducting cab le to stability as a preceded research work. When maintaining the current transfer characteristic between strand cable beyond the reference value with which exoergic in a current transfer part does not worsen a stability, even if the ununiform current arose in between strands, it was shown that the affection on a stability is small. The above-mentioned research result was received and development research of the conductor of the high stability which controlled the current distribution in a conductor was performed. The current distribution in a conductor was controlled and development research of the superconducting conductor of the stranded-cable architecture of reconeiling insurance of a high stability and the reduction of an AC loss was performed. First the current distribution in a conductor and the relation of an AC loss were devised. It is reported by the low-frequency area near an operati … More on frequency from the measurement result of the AC loss of the large-scale supercondueting coil using the cable-in-conduit conductor that an AC loss increases, It is considered as the new factor which obstructs utilization of a large-scale superconducting coil and investigation of the possible cause was hurried. In this research, the element experiment using 2 stranded cables was performed based on the estimate that it is the cause that the ununiformity of the current distribution in a stranded-cable conductor varies to a conductor longitudinal. It was shown that the ununiformity of the current distribution resulting from twist turbulence becomes the possible cause of an AC-loss enhancement, Next based on the research result about the effects of the current distribution in the conductor to stability and AC losses, the design concept of a new-architecture superconducting conductor which made the stability and the low AC loss balance was proposed. The design of a trial production conductor based on this design concept was performed, and the AC loss and the stability were analyzed. Moreover, in order to examine the feasibility of conductor manufacturing, the conductor trial production was performed. Less