Design of Axial Flux HTS Machine Prototype and AC Losses Calculation

With the development of high-temperature superconducting material technology, the structure and performance of superconducting machines have met the requirements of large-scale use. Compared with conventional motors, the power density of superconducting motors can reach more than 10 kW/kg. In addition, it has higher efficiency and torque. In this article, an axial flux high-temperature superconducting motor prototype is designed. The main structure of the motor consists of one rotor disk and stator disk. The stator disk is composed of six ReBCO double-cake coils, and the rotor poles consist of four pairs of alternately distributed sectorial permanent magnets. Based on the structure of the motor prototype, a finite element analysis model is established. Under the rated power condition, the air gap magnetic field and the external field of the superconducting coil are calculated as well as the ac losses of the different positions of the superconducting coil at the corresponding magnetic fields are calculated from the T-A-formulation. Comparison between the relative contribution of the different segments of the coil to the overall ac losses, the relative contribution of the straight section of the coil to the total ac losses is greatest due to the external field.