基于电磁力近似算法的驱动电机NVH快速仿真方法

电动汽车驱动电机产生的电磁噪声是汽车NVH关注的重点问题,对其进行全转速段多工况NVH仿真通常需要耗费大量时间和计算资源。该文通过有限单元分析揭示了电机气隙电磁力随转速变化的规律,并根据这一规律提出了基于外特性曲线的电磁力时间缩放及插值的近似算法。文章采用电磁力到结构网格的映射算法对结构振动有限元模型进行激励力加载,使用声场有限元方法计算电机的辐射噪声,最终实现了车用驱动电机的电磁振动及噪声的快速仿真。使用该方法对车用电机进行全转速段振动噪声仿真,可大大压缩多工况电磁场有限元分析所需的计算时间,提升仿真效率。

A high efficiency NVH simulation methodology for vehicle driving motor based on electromagnetic force approximation

Electromagnetic noise generated from the driving motor used in electrical vehicle is an important topic in the research field of noise, vibration, and harshness(NVH), whose simulation for multiple operating conditions over the full speed range needs a large amount of time and computational resources. In this paper, the dependence of the air gap electromagnetic forces on the motor rotation speed is revealed by means of electromagnetic finite element analysis. Based on the force-speed relation, force scaling and force interpolation algorithms are proposed to approximately calculate the electromagnetic forces for different operation conditions on the external characteristic curve. A force mapping algorithm is presented to apply electromagnetic forces to the structural finite model, and acoustic finite element analysis is used to calculate electromagnetic noise radiated from the motor. The presented NVH simulation methodology can significantly reduce computation time consumed in multiple operation conditions, and observably improve simulation efficiency.