3D Semi-Analytical Modeling and Optimization of Fully HTS Ironless Axial Flux Electrical Machines

•A rapid volume integral modeling approach is developed for HTS electrical machines design and optimization.•The use of particular volumetric basis elements helps to reduce significantly the computation time.•The model is applied to the optimization of an ironless HTS axial flux electrical machine, where the obtained results are comforted by 3D finite element analysis.•The investigations have shown that the considered fully HTS machine has a higher torque density compared to that of conventional ones. In this paper, a three-dimensional semi-analytical approach, based on the volume integral method, is developed to compute the forces and torque in fully high temperature superconducting (HTS) ironless axial flux machine (IAFM). The use of particular volumetric basis elements helps to speed up the computation of the magnetic field. The Maxwell stress tensor method is used for the force and torque calculations, where the electromagnetic state of the superconductor is taken into account. The developed model is then introduced into a multi objective optimization procedure, based on the genetic algorithms, to maximize the magnetic torque and minimize the superconducting wire length in the considered structure, while respecting the constraints linked to the physical and mechanical properties of the considered HTS tape. It is shown that the considered fully HTS machine has a higher torque density compared to conventional one.