A method for calculating critical current of high temperature superconducting machine based on magnetic vector potential

A method for calculating the critical current of high temperature superconducting (HTS) machine using boundary magnetic vector potential constrain and bisection method is proposed in this article. The indirect coupling between superconducting and non-superconducting regions of HTS machine is realized through boundary magnetic vector potential constrain, which avoids the model complexity caused by direct coupling and saves computation time. Taking a 10 kW double-stator HTS machine (DS-HTSM) as an example, the process of calculating critical current through proposed method is given. To verify the correctness and accuracy of proposed method, a direct coupling model of DS-HTSM is established. The results show that there is a high consistency of critical current and magnetic field distribution of direct and indirect coupling models. The calculated results of critical current are in agreement with the experimental in relevant research. The proposed method is quite effective for calculating the critical current of different HTS machines.