할박 배열 축방향 자속 BLDC 모터의 코깅토크 감소

Abstract

The cogging torque of the Brushless Direct Current (BLDC) motor is generated by the attractive force between the permanent magnets (PM) and the stator teeth. It increases proportionally as the magnetic force of the PMs becomes stronger. In particular, in the case of a Halbach array motor which reinforced with magnetic force, the cogging torque acts as a factor that lowers the performance of precision motor control. In this paper, stator skewing method for the reduction of cogging torque was investigated. The method was applied to a Halbach array Axial Flux Permanent Magnet (AFPM) BLDC Motor, and the optimal skew angle to minimize the cogging torque was derived through finite element analysis (FEA). The experimental data verified that the cogging torque, which accounted for 0.2928 Nm of the non-skewed motor, decreased to 0.0327 Nm, which corresponds to 88.8 %.