access icon free Design of slit width to improve space harmonic distribution in a slit stator motor

© The Institution of Engineering and Technology
Received 04/06/2018, Accepted 25/03/2019, Revised 26/02/2019, Published 26/03/2019

This article designs the width of slit-like flux barriers to improve the space harmonic distribution of the air-gap flux density in a slit stator motor. The slit stator motor has slit-like flux barriers at wound teeth of the stator. The stator design can adjust the space harmonic distribution with the slit width. Space harmonic distributions govern torque and losses in motors. For this reason, the dependence of the space harmonic distribution on the slit width should be clarified to design slit stator motors. The dependence is investigated through a theoretical calculation based on a magnetic circuit model and a finite element method analysis. These methods show that a space harmonic producing the drive torque is maximised at a slit width and other dominant detrimental space harmonics are decreased with the increase of the slit width. The improved space harmonic distribution is verified by performing an experiment with a measuring rotor.

Inspec keywords: rotors; air gaps; stators; torque; magnetic flux; magnetic circuits; finite element analysis

Other keywords: motor loss; slit width design; magnetic circuit model; drive torque; slit stator motor; FEM analysis; wound teeth; measuring rotor; slit-like flux barriers; finite element method analysis; space harmonic distribution govern torque; air-gap flux density

Subjects: Other electromagnetic device applications; Finite element analysis; a.c. machines; d.c. machines

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