高温超导线圈绕制工艺及性能测试研究

Study on Winding Process and Performance Test of High Temperature Superconducting Coil

针对高温超导用Bi系高温超导带材,对其在77 K自场下和应变疲劳下的临界电流进行了测试。介绍了超导限流器用大型高温超导线圈及绕制工艺,在77 K自场下对比研究了双饼线圈、螺线管线圈的V-I特性曲线;通过反复试验得到了最佳接头焊接工艺,满足了磁体稳定工作的条件。结果表明:当弯曲次数小于或等于10次时,高温超导带材的临近电流不受径向弯曲次数影响;绕制的高温超导线圈性能良好,77 K自场下的临界电流为168.12 A,当焊接温度达到493 K、搭接长度4 cm、焊料Sn63Pb时焊接效果最佳。

In this paper,the winding process of a large high temperature superconducting coil was introduced,and the best joint welding process was obtained by repeated experiments,which meets the requirement of stable operation of superconducting coils. The current carrying capacity of high temperature superconducting(HTS)strips under the condition of radial bending of strain fatigue,as well as V-I curve of HTS coils,were measured in self-field at the temperature of 77 K.The result indicates:when the bending times were equal or less than 10,the current carrying capacity of HTS strips was unchanged. HTS coils winded with the process in this paper have good performance,and the critical current measured in self-field at 77 K is 168.12 amperes. The best welding result was obtained when welding temperature is 439 K,overlapping length 4 cm and Sn63 Pb was employed as solder.