不对称磁障对IPMSM电磁振动噪声的影响分析

Analysis of Influence of Asymmetric Magnetic Barrier on Electromagnetic Vibration Noise of IPMSM

针对目前一些采用不对称磁障法降低内置式永磁同步电机(IPMSM)转矩脉动的研究并未细致分析其对电机电磁振动噪声产生何种影响的问题,以一台37 kW IPMSM为研究对象,建立了原始电机和具有不对称磁障结构电机的电磁场有限元模型与振动噪声耦合模型,对比分析了不对称磁障结构对电机振动噪声的影响。从理论上分析了永磁电机径向电磁力波的阶次、频率特征,并利用有限元法与二维傅里叶分解法对得到的气隙处径向电磁力波进行分解。建立定子结构有限元模型,对其进行模态分析。在仿真平台搭建振动噪声耦合模型,仿真得到电机定子振动响应与电磁噪声。结果表明,采用不对称磁障的设计方法虽然能降低电机的转矩脉动并且不会牺牲电机输出转矩,但会产生其他倍频的电磁力,增加相对应频率点的振动响应,增大电机的振动噪声,设计时需综合考虑。

In current researches on reducing torque ripple of interior permanent magnet synchronous motor(IPMSM)by asymmetric method,there is no detailed study on the influence on electromagnetic vibration noise of the motor.For this reason,taking a 37 kW IPMSM as the research object,the electromagnetic field finite element model and the vibration noise coupling model of the original motor and the motor with asymmetric magnetic barrier structure are established.The effects of the asymmetric magnetic barrier structure on the vibration noise of the motor are compared and analyzed.The order and frequency characteristics of the radial electromagnetic force wave of the permanent magnet motor are analyzed theoretically,and the radial electromagnetic force wave at the air gap is decomposed by using the finite element method and two-dimensional Fourier decomposition method.The finite element model of the stator structure is established and its modal analysis is carried out.Then the vibration noise coupling model is built on the simulation platform to obtain the vibration response and electromagnetic noise of the motor stator.The results show that,although the design method of asymmetric magnetic barrier can reduce the torque ripple of the motor and does not sacrifice the output torque of the motor,it will generate other frequency multiplied electromagnetic force and increase the vibration response of the corresponding frequency points,and deteriorate the vibration noise of the motor,which should be considered comprehensively in the design.