Evelopment of a Highly-stable Superconductor with Controlled Current Distribution

作为前期的研究工作，我们研究了超导电缆中电流分布不均匀对稳定性的影响。当将绞线间的电流传递特性保持在使电流传递部分的外能不会恶化稳定性的参考值之外时，即使股间产生不均匀的电流，也表明对稳定性的影响很小。在获得上述研究成果的基础上，开展了控制导体中电流分布的高稳定性导体的研制。控制了导线中的电流分布，开展了高稳定性、低交流损耗的复线结构超导导线的开发研究。首先给出了导体中的电流分布和交流损耗之间的关系。据操作员…附近的低频区域报告从大型超导线圈交流损耗的测量结果可知，交流损耗增大是阻碍大型超导线圈使用的新因素，并对其可能的原因进行了探讨。在本研究中，利用两股多股电缆进行了元件实验，估计了多股电缆导体中电流分布的不均匀是纵向向导体变化的原因。结果表明，扭转湍流引起的电流分布不均匀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的影响的研究结果，提出了一种使稳定性和低交流损耗平衡的新型超导导体的设计概念。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，为了验证导线制造的可行性，进行了导线的试制。较少

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