电工技术学报2024，Vol.39Issue(16)：4909-4917,9.DOI:10.19595/j.cnki.1000-6753.tces.230970
接头电阻对CORC电缆交流损耗的影响分析
Analysis of the Influence of Joint Resistance on AC Loss of CORC Cable
摘要
Abstract
The conductor on round core(CORC)cable,spirally wound by high temperature superconducting tapes,will generate AC loss,which increases the heat burden and even endangers the safe operation of the entire superconducting system.In practical applications,joint resistances will inevitably appear in the joints of CORC cable.However,the existing technology is difficult to ensure that the joint resistance of each superconducting tape of the CORC cable be exactly same.The differences of joint resistance will have significant impacts on the AC loss of the CORC cable.Therefore,a 3D finite element model of CORC cable with joint resistance is established,and studies on the influence of joint resistances on AC loss of CORC cable is carries out. A CORC cable based on finite element software is built.Firstly,a small segment is cut at the end of each superconducting tape of CORC cable to simulate the joint resistance,and the geometric model and equivalent circuit model of the CORC cable are constructed.Secondly,it is meshed and optimized.Finally,the Maxwell Equations are solved based on H-formulation.The model can accurately and effectively simulate the influence of joint resistances on the electrical characteristics of CORC cable. The simulation results show that when the transport DC current is applied to the CORC cable with no joint resistance,the transport DC current is evenly distributed to the three superconducting tapes.When the ratio of the joint resistances of the three superconducting tapes is Rt1∶Rt2∶Rt3=1∶2∶3,the ratio of the DC transport current through the superconducting tapes is I1∶I2∶I3=6∶3∶2,which verifies the accuracy of the model.When the AC transport current is applied to the CORC cable,the transport current of the three superconducting tapes is not distributed according to the ratio of the joint resistances,and the phase of the AC transport current in each superconducting tape is also different. The following conclusions can be drawn from the simulation analysis:(1)Uneven joint resistances of the CORC cable directly leads to the inconsistency of the transport current of each superconducting tape.When the DC current is transported,the current distribution of each superconducting tape is mainly affected by the joint resistances.When the AC current is transported,the superconducting tapes have reactance due to their spiral winding structure,so the current distribution and phase of each superconducting tape are affected by the reactance and the joint resistance of the superconducting tape.(2)Due to the joint resistance and reactance of the superconducting tape,when the CORC cable transports AC current,part of the AC current will flow into the former and cause loss.Compared with the AC loss generated by the superconducting tapes,the loss generated by the former accounts for a larger proportion of the total loss of the CORC cable.(3)When the AC current is transported,the AC loss of the CORC cable with even joint resistances is always smaller than that of the CORC cable with uneven joint resistances.The total AC loss of the CORC cable is always positively correlated with the uneven degree of the joint resistances.When the joint resistance distribution type of the superconducting tapes is Large-Large-Small,the AC loss of the CORC cable is most obviously affected by uneven degree of the joint resistances.关键词
高温超导带材/CORC电缆/接头电阻/电流分布/交流损耗Key words
High temperature superconducting(HTS)tape/CORC cable/joint resistance/current distribution/AC loss分类
信息技术与安全科学引用本文复制引用
李超,杨文超,杨嘉彬,李全,信赢..接头电阻对CORC电缆交流损耗的影响分析[J].电工技术学报,2024,39(16):4909-4917,9.基金项目
国家自然科学基金(52107022)和新奥能源研究院材料研发基金(9710K2022-021)资助项目. （52107022）
