The Effects of the Unequal Rotor Slot Arc on Cogging Torque for Flux Switching Permanent Magnet Machines

Abstract

Many of the electric machine researchers are studying the Flux switching permanent magnet (FSPM) machines. The cogging torque is one of the most unwanted parameter for highly sensitive electric machine applications. In this study, the configuration of the unequal rotor slot arc (URSA) to see the effects of the asymmetry for three phase FSPM machine has been studied. The proposed asymmetry contains of presenting different arc angled rotor poles and analyzing the torque performance of them by using 2D finite element analysis (2D-FEA). 12-stator pole/ 10-rotor pole (12s/10p) FSPM machine topology has been chosen for the design. Results proved that unequal rotor slot arc proposition demonstrate good performance in comparison to the symmetric design. Inequality on the rotor slots were simulated by using parametric analysis to minimize the cogging torque. The suggested design indicates a substantial reduction in cogging torque, achieving a conspicuous minimization. Consequently, the suggested using unequal rotor slot arc for FSPM machine has reasonable outcomes.

Keywords

• Flux switching machines
• rotor permeance
• cogging torque
• asymmetric rotor
• permanent-magnet machines
• unequal rotor slot arc

References

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