An approach to the shape optimum design of superconducting synchronous generator

A superconducting synchronous generator (SSG) is characterized by an air-cored machine with its rotor iron and stator iron teeth removed. For this reason, in the case of the shape optimum design of SSG, other design variables different from an iron-cored machine should be considered, which will lead to substantial improvement on the performance. The major design variables that are considered by using 3D finite element method (FEM) in this paper are: (1) field coil width; (2) axial length of magnetic shield; and (3) armature winding method. The end-ring of the armature winding is considered in the calculation of EMF. When it comes to field coil width, as the field coil width enlarges, its effective field increases but the maximum field on the superconductor decreases. This determines the critical current density. This study presents an effective field coil width, axial length of magnetic shield, and armature winding method, and also the analysis is verified by experimental results.