Research On AC Loss Characteristics Of YBCO Soldered Stacked Square Superconducting Wires In Cable Model

With the rapid growth of population and economy in the world,with the continuous increase in power supply demand,the current limited current capacity of conventional cables has become a non-negligible drawback of today's cables.High-temperature superconducting cable is a new type of newly developed cable,which has the advantages of large capacity,high efficiency,and low loss.However,the AC loss caused by this new type of cable will increase the cost of the refrigeration system,which has become one of the important reasons why it is difficult to commercialize large quantities of superconducting cables.High-temperature superconducting wires are critical materials for superconducting cables.When superconducting wires are used in superconducting power equipment,the external magnetic field will affect their critical current and AC loss,especially the magnetic field perpendicular to the surface of superconducting wires.In order to reduce the effect of external magnetic field on the critical current and AC loss characteristics of superconducting wire,this dissertation adopts a new superconducting wire independently researched and developed by Shanghai Jiaotong University to make a cable.The cross-sectional area of this novel superconducting wire is lmmxlmm,which can improve Current carrying capacity and good mechanical and power performance.In this dissertation,firstly,the critical current,AC loss and other characteristics of the single new superconducting square wire were tested and analyzed,and 14 superconducting square wires with the same critical current were selected to make a 50cm inner diameter of 6mm round.Cylindrical YBCO superconducting square cable,secondly from the experimental point of view,the characteristics of the AC loss of the YBCO superconducting square cable,and finally the selection of the hexagonal YBCO cable with the same size as the square cable for comparison,for the lead height,power frequency The analysis of power characteristics,the analysis of the AC loss characteristics of the two,and the impact of AC loss are summarized.The experimental results show that the critical current V-I curve of a single superconducting square wire exhibits a typical superconducting characteristic,and the experimental.results of the AC loss of a single superconducting square wire are in good agreement with the simulation results.In the YBCO superconducting square cable model,the AC losses at different voltage lead heights are equal,and the AC loss of the cable is independent of the frequency change.When the inner diameter and length of the YBCO cable are equal,the loss value of the 1120A cylindrical cable composed of 14 square wires is smaller than that of the 660A cable composed of 6 ordinary YBCO wires,and the square wire cable can effectively reduce the AC loss.