Numerical Analysis Of AC Loss Characteristics Of Stacked High-Temperature Superconducting Tapes

High-temperature superconductors(HTSs)have excellent electromagnetic properties and have broad application prospects in fields such as electric power transmission,strong magnetic field,and traffic.The loss of AC generated by a superconductor in a complex electromagnetic environment is one of the important issues in the development and fabrication of superconducting devices.In the working environment of the superconductor,the generated AC loss will enter the entire superconducting device as a direct heat source,which will not only increase the burden on the cooling system,increase the operating cost of the superconducting device,but also affect the stable operation and safety of the superconducting device.In this paper,based on the finite element method,the AC loss characteristics of stacked HTS tapes in a complex electromagnetic environment are analyzed.Firstly,using the finite element analysis of the H method,with regard to the stacking of HTS tapes in an alternating magnetic field field environment.The effect of the number of stacked layers of HTS tapes and the angle of the alternating magnetic field on the magnetization curve and AC loss was studied.The numerical results show that when the HTS tape is only in the alternating magnetic field environment and other conditions are constant,the magnetization curve of the HTS tape becomes smaller with the increase of the number of layers of the tape,and at the same time,The AC loss of the HTS tape also shows a decreasing trend.When the angle between the applied magnetic field and the wide surface of the superconducting tape gradually increases,the AC loss of the HTS shows an increasing trend whether it is a single-layer tape or a six-layer tape.Secondly,with regard to the stacked HTS tapes in the complex electromagnetic field environment,the equivalence relationship between the alternating current and the alternating magnetic field to the AC loss of the stacked HTS tapes and the impact of complex electromagnetic field environment on the AC loss of the stacked HTS tapes were studied.The results show that the effect of external magnetic field on the AC loss of superconducting tapes is greater than the effect of alternating transport current when the magnetic field amplitude is small.When the number of superconducting tape layers increases,The effect of the applied current and external magnetic field on the AC loss of superconducting tape tends to be linear.In addition,whether the load current is a certain value or the applied magnetic field is a certain value,the influence of the small magnetic field amplitude on the AC loss of the superconducting tape is greater than the effect of the current on the AC loss.