Properties of YBCO films at high current densities: fault current limiter implications
Properties of YBCO films at high current densities: fault current limiter implications
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高电流密度下 YBCO 薄膜的特性：故障限流器的影响
DOI：
10.1109/77.920257
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发表时间：
2001
影响因子：
1.8
通讯作者：
M. Chen
中科院分区：
文献类型：
--
作者：
M. Decroux;L. Antognazza;N. Musolino;E. D. Chambrier;S. Reymond;J. Triscone;O. Fischer;W. Paul;M. Chen
我们研究了基于外延YBCO薄膜的超导带状线在高电流密度下的性能。用短恒流脉冲进行的实验表明，在高电流密度下，准自发高耗散态（HDS）出现。通过仔细测量YBCO线的温度，我们发现当HDS发生时，它的温度仍然低于T/sub c/，表明这种状态不是由热失控引起的。一旦启动，这个HDS开始以大于100m /s的初始速度传播，这比热速度高一个数量级。我们还对YBCO线路施加了恒压脉冲，从而模拟了真正的短路。我们发现，在短路后的几微秒内，HDS沿线路的空间范围与施加的电压呈线性关系。这些结果允许解释在超导故障限流器（SFCL）中观察到的快速开关特性，以及峰值电流通常限制在临界电流的3倍的事实。
We have studied the properties of superconducting strip lines, based on epitaxial YBCO thin films, at high current densities. Experiments performed with short constant current pulses show that a quasi spontaneous highly dissipative state (HDS) appears at high current densities. By carefully measuring the temperature of the YBCO line, we found that its temperature is still below T/sub c/ when the HDS occurs, indicating that this state does not originate from a thermal runaway. Once initiated, this HDS starts to propagate with an initial velocity larger than 100 m/s, which is one order of magnitude higher than thermal velocities. We also applied constant voltage pulses to the YBCO line, therefore simulating a real short circuit. We found that the spatial extent of the HDS along the line, a few microseconds after the short circuit, depends linearly on the applied voltage. These results allow explanation of the fast switching properties observed in superconducting fault current limiters (SFCL) and the fact that the peak current is limited at, typically, 3 times the critical current.