Evaluating the Effects of Electric and Magnetic Loading on the Performance of Single and Double Rotor Axial Flux PM Machines

Abstract

Axial flux PM (AFPM) machines are used particularly in applications requiring a compact structure. Their disc shape topology and axial air-gap have led to a variety of configurations including two popular ones: the yokeless and segmented armature (YASA), and the single-stator singlerotor or single sided machine. In this study, a comprehensive comparative analysis of these configurations is conducted at different magnetic and electric loadings. It is found that at lower loadings, typically employed for air-cooled machines, the torque/ampere characteristics of the YASA machine are almost identical to those of a single sided machine constructed with half the magnet volume. On the other hand, the single sided machine outperforms the YASA machine when the magnet volumes in both machines are maintained equal. However, for higher electric loadings, the torque/ampere characteristics of the YASA machine droop significantly less than those of the single sided machine. The paper includes analytical estimations which are verified with experimentally validated FEA simulations. In addition, the impacts of the armature reaction on saturation and the magnetic flux linkage, the magnet losses and eddy current losses in both machines are also explored. Index Terms-Axial flux permanent magnet, yokeless and segmented armature, YASA, armature reaction, power factor, eddy current losses, magnet losses, torque production.

Multi-Objective Optimization of Yokeless and Segmented Armature Machine for In-Wheel Traction Applications Based on the Taguchi Method

“…Each optimization variable corresponds to the average value of optimization objectives under different levels. For example, the average value of rated torque T ave of variable h m under level 2 is shown in Equation (7). Similarly, the average values of optimization objectives under different levels of other optimization variables can be calculated.…”

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Evaluation of 3D-Printed Magnetic Materials For Additively-Manufactured Electrical Machines

“…However, it is rather difficult to get a neat final shape. Besides, the uneven lamination assembly is extremely time consuming during the production process especially without automated assembly [12]. So, when a core module of a YASA machine is prototyped, manufacturers try to limit the number of different lamination shapes in order to save time and effort during the assembly processes.…”

Full prediction cascade control of permanent magnet toroidal motor with time-varying parameters

“…Permanent magnet synchronous motor (PMSM) has been widely used in the fields of electric vehicle drive system, robot, CNC machine tools, and so on because of its advantages in small size, simple structure, high power, high torque density, and wide speed range (Garza-Alonso et al, 2021;Shi et al, 2020;Wu et al, 2020). With the spatial requirements of modern industry for permanent magnet motors, new permanent magnet motors with different spatial structures have developed rapidly, such as axial-flux permanent magnet motor (Taran et al, 2020), multiport magnetic gear permanent magnet motor (Zhu et al, 2018) and permanent magnet spherical motor (Li et al, 2020;Zhou et al, 2020). These new permanent magnet motors have compact structures and high spatial utilization.…”