Segmented stators ease the winding process, increase slot fill factor, and improve handling and assembly. Segmented stator construction also allows oriented steel with superior magnetic properties, higher permeability, and lower losses in orientation, also known as rolling direction. Therefore, using oriented steel for the segmented stator construction of PMSM may improve machine performance compared to a machine designed with non-oriented steel, such as an increase in average torque and efficiency.Apart from the clear advantages of segmentation, the increased number of segments increases the unavoidable parasitic gaps between the segments, adversely affecting machine performance. Moreover, oriented steel modeling in modern FEA software is inaccurate, as shown in the literature. An improved model was proposed in the literature to resolve this issue, which requires magnetic properties of the oriented steel in between the rolling and transverse directions. This research aims to analyze the performance of the oriented steel segmented stator PMSM and compare it with conventional non-oriented steel stator PMSM. In this research, the magnetic properties of the oriented steel are determined using a devised experimental setup method. In the proposed method, the flux density of controlled amplitude and frequency is imposed in the oriented steel segmented stator using specially designed devices to estimate the BH and loss curves of the oriented steel. The advantage of the proposed method is that it is comparatively less expensive than the specially modified Epstein frame test. Further, a general theory is proposed to determine the impact of segmentation parameters on the selected performance measures: core losses, average torque, cogging torque, and Back electromotive force. Finally, the estimated magnetic properties of the oriented steel are used to model the oriented steel segmented stator PMSM, and its performance is compared with that of the conventional machine. The experimentally-estimated magnetic characteristics of the oriented steel are different from those estimated using the FEA method. Further, the theory to show the impact of segmentation parameters on the machine performance is validated using numerical experiments on two different machine designs with 72 slots/12 poles and 72 slots/8 poles. The estimated properties are used to model the oriented steel segmented stator PMSM with 72 slots/12 poles. Its performance, with different combinations of segment size and parasitic gap, is compared with conventional stator PMSM of the same design at the same drive cycle. For some segment sizes, the segmented stator machine has lower losses. Moreover, the segmented stator machine has higher cogging torque for all segment sizes and unbalanced BEMF for specific segment sizes..
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