基于分磁环的超导双饼线圈电磁特性分析

Analysis of the electromagnetic characteristics of superconducting double-cake coils based on flux diverter

采用二维轴对称H方程法对超导双饼线圈进行了有限元分析,并搭建电磁仿真模型。系统分析了未安装分磁环、单侧安装分磁环和双侧安装分磁环对超导双饼线圈失超稳定性的影响。仿真结果显示,在双侧安装分磁环不仅提高了通流能力,而且比在单侧安装分磁环更具有电磁稳定性。同时,通过仿真分析了分磁环对超导双饼线圈临界电流和交流损耗的影响,双侧安装分磁环显著提升了临界电流、降低了交流损耗。进一步分析可知,当频率由50 Hz不断增加到5 kHz,交流损耗降损率却从84.6%下降到78.5%,表明分磁环在低频下更有利于降低交流损耗。

Finite element analysis of superconducting double-cake coil was conducted by using the two-dimensional axisymmetric H-equation method, and its electromagnetic simulation model was established. The effects of no flux diverter, single-sided flux diverter and double-sided flux diverter on the quench stability of superconducting double-cake coils were systematically analyzed. The simulation results show that installing the flux diverter on both sides not only improves the flow capacity, but also has more electromagnetic stability than installing the flux diverter on one side. At the same time, based on software simulation, the installation of the magnetic separation ring on both sides significantly improves the critical current and reduces the AC loss. Further analysis shows that the AC loss reduction rate decreases from 84.6% to 78.5% when the frequency increases from 50 Hz to 5 kHz, indicating that the flux diverter is more favorable to reduce AC loss at low frequency.