Research On Current Limiting Characteristics Of Cold Dielectric HTS Current Limiting Cable

In recent years,the preparation technology of superconducting tapes has made great progress.The performance of HTS tapes has been continuously improved,which has laid a solid foundation for the research and development of superconducting power equipment and its application.In superconducting power equipment,HTS cable has the advantages of lower loss,larger conveying capacity and smaller area than conventional cable.However,the low impedance superconducting cable widely used in power system,which will increase the short circuit current when the power system fails.In order to solve the problem,superconducting cable and superconducting current limiter can be used in real power network.However,the use of superconducting current limiter will increase the cost of system construction.Therefore,in view of the operation characteristics of HTS cable and superconducting current limiter,the second generation(2G)HTS superconductor can not only transmit large current,but also have the characteristics of limiting fault current.This paper design of HTS current limiting cable and analyzes its current limiting characteristics.The main work as follows:An impact test platform is designed and built using IGBT to test withstand performance of HTS tape and HTS current limiting cable in fault current occasion.Study quench resistance of second generation HTS tape reinforced by stainless steel.Test impact characteristics(100 ms)of this HTS tape.Based on the structure and electromagnetic characteristics of the 2G HTS tape,the paper put forward the concept of current limiting superconducting cable The cable adopts stainless steel wire strand as former,and the second generation HTS tape mainly composed of stainless steel.After the superconducting cable is quenched,the current and temperature distribution of the cable conductor is uniform,which can avoid local overheating.On the basis of the experimental research on the quench resistance and short circuit impact resistance of 2G HTS tape,the paper designed 10 kV/1 kA of HTS current limiting cable.The rationality of the design is verified by the corresponding simulation analysis.According to the conductor structure of cold dielectric high temperature superconducting current limiting cable,the mathematical model of the cable is established.And analyzed the current limiting characteristics,loss of excess and recovery characteristics of the superconducting current limiting cable under the condition of fault current(short circuit time 100 ms).Put the cable into the power system for simulation analysis,this cable can effectively reduce the short circuit current when power system fault.The relationship between current limiting characteristics and length of superconducting current limiting cable is given,which provides an important basis for practical application of superconducting current limiting cable.