不同并联模式对YBCO超导带材失超恢复特性的影响

Influence of different parallel modes on quench recovery characteristics of YBCO tapes

失超和恢复是电阻型超导直流限流器的关键特性,由于单根钇钡铜氧(YBa2Cu3O(7-x),YBCO)超导带材载流能力有限,为传输足够大的额定电流,避免超导元件限流时产生过多的焦耳热,所以通常要采用并联分流电路组成限流器的限流元件.针对平行并联空间利用率低和无绝缘堆叠并联换热效率低的问题,提出一种带绝缘的堆叠并联模式.通过不同并联模式的理论传热分析,得出带绝缘堆叠并联模式主要通过增大传热面积和提高传热系数来加快超导带材的失超恢复过程.对不同并联模式的带材进行直流冲击实验,实验结果表明:对YBCO-YBCO堆叠并联导体,导体间带绝缘比无绝缘时失超恢复时间减少30%~50%;对YBCO-不锈钢带堆叠并联导体,导体间带绝缘比无绝缘时失超恢复时间减少5%~10%.

Quench and recovery are key characteristics of DC Resistive-type Superconducting Fault Current Limiter(R-SFCL).In actual application,the current-carrying capacity of a single YBCO tape is limited.For this reason,to transmit a large enough rated current and avoid generating excessive Joule heat when the superconducting element is limiting the short-circuit current,it is necessary to use a parallel shunt circuit to form the current-limiting element of the R-SFCL.To address the problems of low space utilization in horizontal parallel and low heat transfer efficiency in stacked parallel without insulation,a stacked parallel mode with insulation is proposed.Through the theoretical heat transfer analysis of different parallel modes,it is concluded that the stacked parallel mode with insulation accelerates the quench recovery process of superconducting tapes mainly by increasing the heat transfer area and raising the heat transfer coefficient.Then,DC impact experiments are carried out on tapes with different parallel modes.The experimental results show that for YBCO-YBCO stacked parallel conductors,the quench recovery time of YBCO tapes in stacked parallel with insulation is reduced by 30%-50%compared with that without insulation.And for YBCO-stainless steel stacked parallel conductors,the quench recovery time of YBCO tapes in stacked parallel with insulation is reduced by 5%-10%compared with that without insulation.