超导电力设备中YBCO超导带材不均匀性对载流特性的影响  

Influence of Inhomogeneity of YBCO Superconducting Tape on Current Carrying Characteristics in Superconductive Electrical Equipment

作　　者：谭亚雄 文明乾 周湶[1] 罗书山 潘家骏 TAN Yaxiong;WEN Mingqian;ZHOU Quan;LUO Shushan;PAN Jiajun(State Key Laboratory of Power Transmission Equipment&System Security and New Technology(Chongqing University),Shapingba District,Chongqing 400044,China;State Grid Nantong Power Supply Company,Nantong 226000,Jiangsu Province,China)

机构地区：[1]输配电装备及系统安全与新技术国家重点实验室(重庆大学),重庆市沙坪坝区400044 [2]国网江苏省电力有限公司南通供电公司,江苏省南通市226000

出　　处：《电网技术》2021年第3期1150-1157,共8页Power System Technology

基　　金：国家重点研发计划项目(2017YFB0902300);国家自然科学基金项目(51907012);中央高校基本科研业务费专项资金资助项目(2018CDXYDQ0002)。

摘　　要：随着第二代高温超导带材技术的发展,YBCO超导带材在超导电力应用中愈加广泛。但超导电力设备中依然存在像制备或运行过程中产生的内部缺陷等影响超导体稳定性的因素,对超导电力设备的运行可靠性产生影响。为研究超导电力设备中超导带材的内部缺陷造成的不均匀性对带材载流特性的影响。先通过磁探针扫描法研究了带材应力型缺陷对临界电流密度的不均匀退化的影响,并通过建立缺陷仿真模型与扫描电子显微镜(scanningelectronmicroscope,SEM)微观照片分析了临界电流退化的机理。随后通过实验研究了宏观缺陷的不均匀性对超导带材载流特性的影响趋势。结果表明,超导带材在应力下产生的内部缺陷会造成超导带材临界电流的退化与不均匀性,主要原因是由超导层结构损伤造成的临界电流密度退化与微裂纹造成的超导通流面积降低造成的。超导带材的载流能力不仅受到局部临界电流退化程度的影响,更是受到沿电流方向优先失超区域面积的影响。所得研究结果可以为超导带材的制备与超导电力设备的载流设计提供有益的参考。With the development of the second generation high-temperature superconductivity(HTS) tape technology, YBCO superconducting tapes are increasingly widely used in superconducting power applications. However, there are still some factors that affect the stability of superconductors, such as internal defects of tapes, which endangers the stable operation of high current transmission superconductors. The purpose of this paper is to study the influence of the inhomogeneity of the superconducting tapes caused by the internal defects on the current carrying characteristics of the tapes. First, the effect of stress-induced defects on the degradation of critical current density is studied in magnetic probe scanning method, and the mechanism of critical current degradation is further analyzed by establishing a defect simulation model and scanning the SEM micrographs. Then, the influence trend of the inhomogeneity of macroscopic defects on the current carrying characteristics of superconducting tapes is studied through experiments. The results show that the internal defects of the superconducting tapes under stress will surely cause the degradation and inhomogeneity of the critical current. The major reasons of it are the degradation of the critical current density caused by the damage of the superconducting layer structure and the reduction of the superconducting flow area caused by the micro-cracks. That is, the current carrying capacity of superconducting tapes is not only affected by the degradation of local critical current, but also by the area of the priority quench region along the current direction. Research can provide useful reference for the preparation of superconducting tapes and the current carrying design of the superconducting power equipment.

关 键 词：YBCO超导带材 不均匀性 内部缺陷 载流特性 

分 类 号：TM721[电气工程—电力系统及自动化]