Prediction of AC Losses in $\hbox{MgB}_{2}$ Superconducting Wires as a Function of Transport Currents and Temperatures

Abstract

We propose two methods to predict the AC transport current losses of MgB2 superconducting wires with respect to various operating currents (Itr) and temperatures (T). Firstly, the transport current loss was estimated by a numerical method (finite element analysis). In order to consider the highly nonlinear behavior of the superconducting properties according to magnetic flux density (B) at each temperature, the measured Jc - B - T characteristics were used in the calculation. The numerical results were compared with these of conventional Norris theory and showed quite good coincidence. A second method to predict the transport current loss at various temperatures, which used a loss at a specific temperature and the critical current data, is suggested. We deduce a formula for the prediction of the loss by a simple analogy through normalization, which performs excellently. The comparison of the transport current loss values calculated using the two methods is addressed.