Decisive influence on torque ripples of permanent Magnet assisted Synchronous Motor by the carrier harmonics

In this paper, decisive influences of the carrier harmonics on torque characteristic for Permanent Magnet assisted Synchronous Reluctance Motor (PMa-SynRM), which has been purposely designed for EV drive system, is numerically investigated. In the design process of PMa-SynRM, stator skew and short pitch winding are adopted in order to reduce torque ripple causing the acoustic noise, vibration. First of all, not only the specification of the PMa-SynRM, but the reduction design process and the performance characteristics such as torque production and ripples are presented. Subsequently, the remarkable torque analysis result, that is obtained using 3-D modeling considering skewed stator structure and the carrier harmonics, is covered in priority. Meanwhile, numerical analysis of its performance is carried out with the Finite Element Method (FEM).