Research On The Transport Current Characteristics Of Three New Kinds Of Square Wires

High-temperature superconducting materials can be widely used in defense,transportation,medical and other fields due to their high current carrying capacity and low power consumption.However,the superconductor is affected by an external magnetic field during energization,resulting in changes in its AC loss and critical current.The structure of the three new square wires is square,which can effectively reduce the influence of external magnetic field on the characteristics of superconducting tape.Therefore,this thesis studied the energization characteristics of three new square wires.First,the basic characteristics of three new square wires were studied.Experimental measurements were made from DC V-1 characteristics and bending diameter and axial tensile force,respectively.Secondly,the loss characteristics of three new square wires were studied.In terms of self-field loss characteristics,the accuracy of the results is ensured by measuring the self-field loss by means of electrical measurement for three new square single wires.In terms of magnetization loss characteristics,it is mainly calculated by experiments and simulations.Methods The effects of three new square wires on magnetization loss at different frequencies,structures and different field angles were studied.Finally,the AC loss characteristics of three new square wire cable structures are studied.Three kinds of cable simulation models based on three new square wires were built in the simulation software COMSOL Multiphysics by H equation.The accuracy of the simulation results was verified by simulation calculation and Norris theoretical value,and the AC loss characteristics of the three cable models were analyzed.The results show that the three new square wires exhibit good superconducting properties in both bending diameter and axial tensile testing.The self-field loss results show that as the stacking narrow band increases in the three new square wires,the critical current of the square wire becomes larger and the self-field loss increases.The magnetization loss test shows that the frequency does not affect the magnetization loss of the square wire,and the structure of the square wire and the difference in field orientation affect the magnetization loss.In the three new square wire cable models,the accuracy of the simulation model is verified by comparing the simulation results with Norris theoretical values.