Optimal Design of PCB Coreless Axial Flux Permanent Magnet Synchronous Motor With Arc Windings

The coreless axial flux permanent magnet synchronous motor with printed circuit board stator (PCB motor for short) has attracted research interests for many advantages, such as flexible and precise winding design, low toque ripple, noiseless operation and simple manufacturing process. The motor performance, however, highly depends on its wiring design, which should be carefully optimized. In this article, an arc-shaped distributed winding is adopted due to its higher efficiency. The PCB motor has a 3D magnetic field distribution, which makes its optimal design very difficult since the 3D finite element analysis is usually required. In this article, an analytical model of PCB motor including 3D magnetic field, arc-shaped winding flux linkage and eddy current loss is firstly deduced. On this basis, a multi-objective optimal design is then carried out to design a PCB motor for a vacuum cleaner. Compared with the concentrated winding, the arc winding can achieve a 3% efficiency improvement. Finally, a 130 W prototype and testbench were built and the presented analytical model is verified by experiments. The results show that there is little difference between calculation and experiment. The presented method effectively simplifies the design process of this kind of motor and shortens the design time.