Study of new PCB winding configurations for high-torque slotless permanent-magnet motors

Details

Supervisors

Dehez, Bruno

Faculty

Ecole polytechnique de Louvain

Degree label

Master [120] : ingénieur civil électromécanicien, à finalité spécialisée: mécatronique

Abstract

Flex-PCB winding technology is an innovative technique used in high power density slotless micromotors with permanent magnets. This technique could be used in high-torque applications, where large-radius motors are necessary. However, the flex-PCB winding technology cannot be used as such at large radii because of limited PCB length. Several adaptations are thus necessary, notably the segmentation of the winding into multiple PCB segments. This Master's thesis studies two segmented winding topologies, namely the overlapping distributed winding topology and the non-overlapping concentrated winding topology. Those allow to use PCB windings for applications requiring high torque and thus large motor radius. It is shown that at high radii, when the number of PCB segments becomes high, the concentrated winding topology outperforms the distributed one. On the contrary, at low numbers of segments, the overlapping topology shows efficiency close to the non-segmented winding configuration. Based on an industrial case study that imposes operating point and dimensions, both winding structures have been optimized based on custom-developed physical models. A motor using the concentrated winding topology was then built and tested for the purpose of an experimental validation.