YBCO薄膜过电流失超特性实验及分析

YBCO薄膜材料作为电阻型高温超导限流器的限流元件具有单位通流长度耐压高,失超后不易损毁等优点.本文设计一套实验设备,在不同幅值交流电源条件下,对YBCO薄膜过电流失超特性进行了测量.实验得到了在不同过电流作用下YBCO薄膜的阻抗及电压随时间的变化关系.大量实验数据表明,YBCO对短路电流有很好的限流效果.并且动作迅速,失超后有效限流电阻大.结合实验数据,文中将YBCO薄膜的过电流失超过程分为三个不同阶段.对应于不同幅值的交流电源,分析了不同阶段YBCO的电阻发展过程.本文得到的结论对YBCO薄膜限流元件的建模及失超传播分析有着重要的参考意义.

EXPERIMENT AND ANALYSIS FOR QUENCH PROPERTIES OF YBCO THIN FILM UNDER OVERCURRENT

YBCO thin film has the advantages of high voltage drop tolerance per unit length and being hard to be destroyed after the complete quench as a current limitation element of a resistive type SFCL. In this work, we designed a set of experiment equipment. Under different peak values of AC source, the quench characteristics of YBCO thin film were tested experimentally. In the experiments, the relationships between impedance and time, voltage drop and time were obtained. Experiment data proves that YBCO thin film can limit short circuit current efficiently. Furthermore, it has a small action time and large impedance. Together with the experimental data, we found that the quench process of YBCO thin film under overcurrent could be divided into three stages. In terms of the different AC voltage sources, we analyzed the impedance development at different quench stage. The conclusions we get in this paper are very important for the modeling of YBCO thin film and analysis of quench propagation under overcurrent.