Quasi-3D를 활용한 극 수 변화에 따른 저속 고토크 AFPM 모터의 경향성 연구

Abstract

This study analyzes the performance of a low-speed, high-torque axial flux permanent magnet (AFPM) motor for different pole and slot numbers using a quasi-three-dimensional (3D) method. The AFPM motor has a single-stator, double-rotor configuration, where the radial direction is divided into N layers. Two-dimensional analyses are conducted for each layer. The results are integrated to approximate 3D effects. The average torque, induced voltage, no-load back electromotive force, and efficiency characteristics are compared for various pole/slot combinations considering copper and iron losses. In addition, the performance variations due to changes in the pole and slot numbers are quantitatively evaluated. The average error between the quasi-3D finite element analysis (FEA) and 3D FEA results is approximately 2.77%, thereby verifying the accuracy of the proposed method. The 24-pole/36-slot configuration demonstrates the best performance within the considered design range. These results indicate that the quasi-3D method is effective in the preliminary design stage. Furthermore, it can serve as a useful guideline for pole and slot number optimization in AFPM motors for low-speed, high-torque applications.