300 kvar超导同步调相机样机的转子磁体设计与测试

正在研制的300 kvar高温超导同步调相机样机采用二极转子结构,每极上堆叠四组跑道形双饼高温超导线圈,线圈之间使用增强型超导电流桥接头结构来降低磁体内部的接头电阻。通过有限元软件对超导转子磁体的静态磁场分布进行了三维仿真计算,根据计算结果和超导带材临界电流-磁场-角度依赖性数据,得到该超导转子磁体在30 K温度的工作电流不能超过333 A。磁体制造完成后,对磁体以不同的升流速度进行了液氮下的通流实验,结果显示,超导转子磁体在液氮下能够安全通流50 A。在通流实验中,测量得到超导转子磁体内部各接头的电阻值均小于1μΩ。

Design and test of the rotor superconducting magnet for a 300 kvar HTS synchronous condenser prototype

The 300 kvar HTS synchronous condenser prototype had a two-pole rotor structure, with four double-pancake race-track type HTS coils stacked on each pole. Enhanced superconducting current bridge joints were installed to connect adjacent coils to reduce joint resistance inside the rotor magnet. The static magnetic field distribution of the rotor magnet was simulated in 3 D by using finite element method. According to the simulation and I_c-B curves of HTS tape, we found that the operation current of the rotor magnet should be kept less than 333 A at 30 K. Furthermore, transport tests of the magnet were carried out at different current ramping rates in liquid nitrogen. The results show that an operation current of 50 A is safe. The resistance value of each joint is less than 1 μΩ in general.