Design of Three-Phase Flux-Reversal Machines With Fractional-Slot Windings

Influence of Adjacent Teeth Magnet Polarities on the Performance of Flux Reversal Permanent Magnet Machine

“…3, for the NS-SN, p m =N s /2=6 and harmonics which are odd times of pm exist, e.g., the 6 th and the 18 th . It should be noted that both the 6 th (m 1 =1) and the 18 th (m 1 =3) harmonics are of considerable magnitude due to the specific distribution of the PM MMF [10]. In addition, it is found that the PM MMF is mainly subjected to the modulation of the fundamental permeance distribution, i.e., k 1 =1, thus producing additional field harmonics, e.g., the 4 th , the 8 th , and the 20 th .…”

“…In [16], a FRPM machine of NS-SN arrangement is analyzed based on a 'fictitious' magnetic gear, from which the performance expressions are analytically derived. Further, the equivalent pole pair number p eq of NS-SN is proposed in [10,16], which reflects the flux distribution inside the stator and rotor core, and can be used to determine the winding connections according to the star of slots of the conventional rotor-PM machine, of which the fundamental pole-pair number of the armature winding is p eq .…”

“…The authors are with the Department of Electronic and Electrical Engineering, The University of Sheffield, Sheffield S1 4DE, U.K. (e-mail: hli53@ sheffield.ac.uk; z.q.zhu@ sheffield.ac.uk). slot and rotor pole combinations have been identified [9,10]. Secondly, the full-pitch distributed-windings (DW) with high winding factor can be adopted to improve the torque density in some slot/pole combinations [11][12][13].…”

Optimal Number of Magnet Pieces of Flux Reversal Permanent Magnet Machines

“…It states that the 6/14 stator slot/rotor pole FRPM machine with full-pitch distributed winding has 50% higher torque than its counterpart with concentrated winding. In [13], the optimal rotor pole number of the FRPM machine is revealed based on analytical equations. It shows that the 14-pole-rotor is preferred for the 12-slot-stator.…”

Analysis of Flux-Reversal Permanent-Magnet Machines With Different Consequent-Pole PM Topologies

“…LUX reversal permanent magnet (FRPM) machines have advantages of robust rotor structure, simple stator structure and easy heat management of PMs, making them promising in low-speed and high-torque applications [1][2][3][4][5][6]. However, for conventional FRPM machines with PMs mounted on the inner surface of stator teeth, the large equivalent air-gap length resulted from surface-mounted PM (SPM) topology limits the field modulation effect of rotor teeth, thus impairing the torque performance [7,8]. In [9], one kind of consequent-pole PM (CPM) topology is proposed to replace the SPM topology, which is beneficial to improve the armature field and the resulted torque, as well as to reduce the PM volume, as shown in Fig.…”