Design, Analysis, and Torque and Induced Phase Voltage Improvement of an Axial-Flux Permanent-Magnet Synchronous Machine

In this manuscript, a new axial-flux permanent-magnet machine (AFPMM) is designed, analyzed, improved, and successfully tested. A double-sided AFPM generator with four layers of stator winding is initially designed using a well-known quasi-3D analytical method. Then, the designed machine is simulated using commercial software. It is shown that modification techniques are required to improve the performance of both the torque ripple and the ratio of the third to the fundamental harmonics of the induced voltage. Therefore, a new improvement technique is proposed, in which the layers of the stator winding are shifted relative to each other. While this new technique significantly improves the third harmonic problem, the design still has a high torque ripple and, thus, it is suggested to combine the proposed method with the conventional magnet shifting technique. It is revealed numerically that the resulting combination properly resolves both third harmonic and torque ripple problems. Therefore, this design is considered the main design of the present manuscript. In the end, a prototype of the main design is manufactured and tested. It is shown that the measurement results are in good agreement with those of numerical software.