Optimal Design of Permanent Magnet Structure to Reduce Unbalanced Magnetic Pull in Surface-Mounted Permanent-Magnet Motors

Abstract

For the surface-mount permanent magnet synchronous motors (SPMSM) with fractional slot concentrated windings, the winding distribution of per phase under different poles is uneven, which results in unbalanced magnetic pull (UMP) between the stator and rotor. UMP has an important impact on the performance and service life of the motor. In this paper, a new permanent magnet (PM) structure is proposed to reduce UMP and torque fluctuation of the fractional slot SPMSM. Furthermore, a 48p/54s SPMSM is taken as an example, the proposed PM structure is optimized by the Taguchi method which can comprehensively consider the control factors and noise factors. The effects of various variables and process error on UMP, torque fluctuation and robustness of results are analyzed respectively. Finally, the optimized PM structure is obtained, which improves the operation stationarity. INDEX TERMS Fractional slot SPMSM, unbalanced magnetic pull(UMP), torque fluctuation, Taguchi method.

Rotor topology optimization and electromagnetic performance analysis of interior permanent magnet synchronous motors for electric vehicle applications

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A coreless axial flux‐switching generator for micro‐wind turbine application

“…Since one of the main disadvantages of the AFFSPM machine is cogging torque, it is necessary to reduce the cogging torque as much as possible in the design process. Therefore, the Taguchi method is used to reduce the maximum cogging torque of the machine 21,22 . The steps of the Taguchi method are shown in Figure 5.…”

Investigation of Six-Phase Surface Permanent Magnet Machine With Typical Slot/Pole Combinations for Integrated Onboard Chargers Through Methodical Design Optimization

“…Performance-wise, the main criteria when designing an SPM machine for the integrated charging process of EVsbesides the developed torque and core lossesare radial forces, irreversible demagnetization, and cost [22][23][24][25]. Even though considerable design optimization work has been reported in the literature, a concept satisfying all the above-mentioned objectives has not been conceived so far.…”

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