MgB2超导圆线基底交流损耗的计算分析

二硼化镁(MgB2)超导体在非铜氧化物陶瓷超导体中具有最高临界转变温度,给超导应用带来了新的契机.铁与镁不反应,且价格低廉,在需要热处理的超导成材工艺中,常常采用铁作MgB2的基底;然而,这种高磁导率的材料有可能增大基底的损耗.本文采用有限元分析软件ANSYS计算了工频下不同材料基底超导圆线传输交流的基底损耗,分析了基底损耗与电流大小、基底厚度之间的关系,对双层基底的损耗也进行了研究.本文的结果对于适当选取截面尺寸、基底材料和工作电流以期减小交流损耗,具有一定参考意义.

AC LOSSES OF CLADDING OF SUPERCONDUCTING ROUND WIRE

The recently discovered new superconductor MgB_2 is promising superconductor for potential engineering applications due to its encouraging values of the highest known transition temperature for a non-copper-oxide superconductor and the absence of a weak link in MgB_2. The most proper sheath material of MgB_2 seems to be a pure iron showing less reaction with MgB_2, good formability and low price. However, the ferromagnetic cladding maybe enhances the total ac losses of superconducting wires in application. In this paper, we calculated transport current losses of cladding under various conditions by the finite element analysis program ANSYS. Based on the calculation datum, the dependences of superconductor cladding losses on transport current and cladding thickness were analyzed. The case of double claddings was discussed as well. The results help to analyze the total losses of MgB_2 superconductor wires and to choose cross section and cladding material of MgB_2 superconductor.