Field simulation studies for a high temperature superconducting synchronous generator with a coreless rotor

A series of 2D and 3D modelling investigations have been undertaken to evaluate and optimise magnetic field distributions in a high temperature superconducting synchronous generator with a coreless rotor. Such design studies are essential to determine if the required air-gap flux density is achievable and at the same time maintaining the total harmonic voltage content within desirable limits. Moreover, due to the anisotropic properties of the superconducting tapes, the presence of carefully designed flux diverters is required in order to reduce the magnetic field normal to the broad face of the tape. It is therefore necessary to model and optimise the shape and position of the flux diverters to minimise the undesirable magnetic field components. Since a 2D model does not take into account the effect of the end leakage flux, a 3D model was used to confirm the effectiveness of the design changes.