Winding Coefficient Calculation and Harmonic Suppression of Axial Flux Permanent Magnet Machine with PCB Winding

Currently, the performance calculation of axial flux permanent magnet machine (AFPMM) with PCB winding is mainly performed by finite element analysis (FEA) and analytical method. In contrast, the analytical method is more applicable in preliminary design and optimization calculations, while the 3D FEA is more applicable for verification of the final solution. However, when the analytical method is used, calculating the winding coefficient is crucial. It is related to the selection of the pole‐slot combination, which directly affects the back electromotive force (EMF) and the magnetomotive force. It even affects the power factor and operating efficiency. This paper focuses on the calculation methods of winding coefficient for different PCB windings. Then, the influence regulation of PCB winding geometrical parameters on the fundamental and harmonic winding coefficients is investigated. In that way, a new winding structure is proposed to suppress the harmonic of back EMF. The correctness of the studied method is verified through 3D FEA and experimental study of the prototype. The proposed new structure is effective for harmonic suppression of back EMF. © 2025 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC.