Open‐Circuit Magnetic Equivalent Circuit Model for Single‐Side Double‐Row Stator Axial Flux Wound Field Machine

ABSTRACT

The single‐side double‐row stator axial flux wound field (SSDRS‐AFWF) machine takes advantage of the inner space in the radial direction, which features a higher torque density. Although the finite element analysis (FEA) method could accurately predict the performance of the machine, it is time‐consuming due to the high calculation load of the 3D FEA, which is challenging for machine optimisation. In this paper, a 3D open‐circuit magnetic equivalent circuit model is proposed for rapid performance analysis of the SSDRS‐AFWF machine. This model utilises different discretisation levels for the machine components according to the local magnetic saturation condition, and the double‐cross structure is introduced in the air gap to improve the modelling accuracy. The auto connection method is given in the proposed magnetic circuit model to consider the rotor rotation. The accuracy of the open‐circuit MEC model is verified by the comparison of FEA and MEC with the error under < 2.5%. The accuracy of the proposed MEC method is verified under different excitation magnetomotive force and size parameters.