电动汽车拍振问题分析及改进

某电动汽车的空调系统存在间歇性异常振动噪声,严重影响驾乘舒适性。文章首先采用分别运行法快速锁定了压缩机和冷却风扇为故障相关零部件,并基于零部件结构特征分析、拍振理论分析、时域数据分析和频谱分析确认该故障为拍振;然后通过传递路径分析及试验确认了该拍振故障的作用机理;最后针对压缩机和冷却风扇两个关键零部件,分别基于源、路径两个方面提出了多种改善措施并通过单品及整车验证确认了改善方案的有效性。分析结果表明,降低振源激励、提升传递路径隔振能力可有效处置拍振问题,车内噪声降低可达8.1 dB(A),降幅约为13.94%。

Analysis and optimization of beat vibration for an electric vehicle

Intermittent abnormal vibration and noise is generated in the air conditioning system of an electric vehicle, which seriously affects the driving comfort. Firstly, the fault parts are identified as compressor and cooling fan by the separate operation method. The fault is confirmed to be the beat vibration by the structural analysis of parts, the theoretical analysis of beat vibration and the analyses of time domain data and spectrum. Then, the mechanism of the beat vibration is confirmed by transmission path analysis and test. Finally, for the two key components of compressor and cooling fan, a variety of improvement measures are proposed in terms of source and transmission path, and the effectiveness is verified by the parts and vehicle tests. The results show that the beat vibration can be effectively eliminated by reducing the excitation of vibration source and improving the vibration isolation of transmission path, and the vehicle interior noise can be reduced by 8.1 dB(A), the reduction ratio is about 13.94%.