采用磁性槽楔改善无刷直流电机的气隙磁场

Using magnetic slot wedge to improve the air-magnetic field of brushless direct current motor

在永磁无刷直流电机(PMBLDC)中,转矩脉动是需要解决的主要问题之一。对引起转矩脉动的主要因素——齿槽效应,进行了仿真分析。为了减小因齿槽变化而引起气隙合成磁场的畸变,采用磁性槽楔以达到减小槽口宽度的效果,使气隙沿周向趋于均匀。通过有限元分析软件——ANSYS软件,对同一无刷直流电机在相同载荷情况下进行仿真比较,结果表明装有磁性槽楔的电机要比无磁性槽楔的电机气隙磁密波形平滑,气隙磁场波动明显减小,因此采用磁性槽楔是可以使气隙磁场波形更趋于矩形波,减小气隙磁阻的变化,削弱磁阻转矩,进而减小转矩脉动。同时,仿真结果也显示了采用磁性槽楔能起到减小永磁体漏磁的作用。

To permanent magnetic brushless direct current （PMBLDC） motors, torque tipple is one of the major problems to be solved. In this paper, the main factor-cogging effect that cause torque tipple is simulated and analyzed. Magnetic slot wedge is used to reduce the notch width and makes the air equality along the circle for reducing the aberrance that is caused by tooth-slot variety. Finite element analytic software-ANSYS has been used to a PM- BLDC motor in no-load and under-load for comparing the simulation results. From the analysis result it can be found that the air-magnetic field can become more smoothly when the motor is used with the magnetic slot wedge. Further more the air-magnetic field fluctuates can be reduced evidently. It is proved that using magnetic slot wedge can make the air-magnetic field wave get more close to rectangle wave, and reduce the variable of air-reluctance, and decrease the reluctance torque and the torque tipple. Mean while, the result of simulation shows that using the magnetic slot wedge can also reduce the leakage of permanent magnetic.