Experimental Analysis Of Effect On Quench Properties Of Hts Tape With Soldring And Local Defferents

In order to meet the needs of superconducting magnet of stable operation and quench protection,the experimental analysis was carried out in this paper on the quench properties of HTS(high temperature superconductor)tape.The goal is to analyze MQE(minimum quench energy)and NZPV(normal zone propagation velocity)of HTS tape with various conditions of superconducting magnet.The calculation will help the quench protection design of HTS magnet.Based on the research and significance of the topic,firstly HTS tape quench properties testing system has been designed.It contained two parts.The first part is critical current testing system,whose role is to test the critical current of HTS tape and confirm the transport current of quench test.The second part is quench properties testing system,whose role is to test MQE and NZPV that is indicated with voltage and temperature criterion of HTS tape.The difference between YBCO tape and Bi2223 tape about MQE and NZPV was analyzed.The result will help the choice of tape which is made of the HTS magnet.Then respectively the quench properties of YBCO tape and Bi2223 tape were investigated on various conditions of HTS magnet operating.The first condition is internal defect in the tape.The second is the difference of partial magnetic.The third is soldering joint in the tape.Firstly there are some internal defects in HTS tape absolutely.In this paper the experiment of effect on critical current of HTS tape with bending recovery was carried out.The bending strain was confirmed for quench experiments.The internal defects were formed by bending strain in HTS tape.The effect on quench properties of HTS tape with internal defects was investigated experimentally.The law of quench properties was mastered.Then the magnetic field of HTS magnet was analyzed by ANSYS simulation.The result showed the phenomenon of magnetic field inhomogeneity in HTS magnet.The effect on quench properties of HTS tape with the difference of partial magnetic was analyzed.The relation between quench properties and magnetic field was discussed.Finally there may be some soldering joints in HTS magnet.The influence of the joints on the critical current was measured.The effect on quench properties of HTS tape with different length of the soldering joints was carried out and analyzed.The calculation will provide the reference data for quench protection design of superconducting device.