Comparison of slip surface and moving band techniques for modelling movement in 3D with FEM

Purpose To compare slip surface and moving band techniques for modelling movement in 3D with FEM. Design/methodology/approach The slip surface and moving band techniques are used to model the rotation of electrical machines in 3D with FEM. The proposed techniques are applied to a permanent magnet synchronous machine. The comparison is carried out at no-load for the electromotive force (EMF) and the cogging torque. The torque is also compared for the short circuit case. Findings For both the locked-step and moving band approaches there is no difficulty in establishing the scalar potential and potential vector formulations. However, if step displacement is not equal to the mesh step, the results can show numerical irregularities. Some improvements have been proposed in order to limit this problem. Originality/value The results of the EMF and the cogging torque are improved.