Electric-magnetic-force characteristics of rare earth barium copper oxide superconductor high-field coils based on screening effect and strain sensitivity  

作　　者：Wenhai ZHOU Youhe ZHOU 

机构地区：[1]Key Laboratory of Mechanics on Environment and Disaster in Western China,The Ministry of Education of China,College of Civil Engineering and Mechanics,Lanzhou University,Lanzhou,730000,China [2]School of Petrochemical Technology,Lanzhou University of Technology,Lanzhou,730050,China

出　　处：《Applied Mathematics and Mechanics(English Edition)》2022年第8期1249-1268,共20页应用数学和力学（英文版）

摘　　要：Rare earth barium copper oxide(REBCO)is the most researched and commercialized second-generation high-temperature superconducting material.Due to the anisotropic structure,strong deformation sensitivity,and central field errors caused by screening current effects,it is still a challenge for commercialization applications.In this study,the transversely isotropic constitutive relationship is selected as the mechanical model based on the structural characteristics of REBCO tapes,and suitable microelements are selected to equate the elastic constants using their average stress-strain relationships.Then,a two-dimensional axisymmetric model for coils wound by single-layer tapes is constructed to analyze the dependence of the electric-magnetic-force distribution in the tape on the strain.Finally,the anisotropic approximation of the homogenized bulk method is used to equate large-turn high-field coils,and the electric-magnetic-force distribution characteristics of the coils with/without screening effects and mechanical strain conditions are investigated,respectively.The results reveal that the mechanical strain has a weakening effect on the electromagnetic field distribution of superconducting tapes,but causes a significant enhancement in the force field distribution.In the presence of 0.5% mechanical strain,the maximum weakening of the peak value of the current density and the critical current density inside the high-field coil can reach about 8% and 13%,respectively,with a nearly 5 times increase in the peak stress.The screening current makes the current field distribution inside the coil improve by about 10 times.The screening current induced magnetic field can reach up to 0.8 T,making the relative error of the high-field coil center up to 7.8%.

关 键 词：screening current strain sensitivity mechanical behavior rare earth barium copper oxide(REBCO)high-field coil electromagnetic field distribution 

分 类 号：O34[理学—固体力学]