电动汽车空调系统异响分析与评价

某电动物流车空调系统存在间歇性轰鸣异响，严重影响驾乘舒适性。文章首先采用分别运行、试错排除等工程方法并结合频谱分析快速定位噪声源(电动压缩机)及主要传递路径(安装支架)；接着运用模态测试、CAE仿真等手段，确认该轰鸣异响源于电动压缩机振动激励经支架总成共振放大并传递至车身致使地板薄壁钣金局部共振产生的结构噪声；然后对源、路径和响应3个方面逐一分析，提出2种改进方案进行单品及实车验证；最后，运用客观参量和烦恼度综合指标对改进前后的车内声品质进行评价分析。结果表明，改进传递路径可快速有效处置该空调系统轰鸣异响问题，噪声峰值降低了19 dB(A)，烦恼度降低72.1%，车内声品质得到显著改善。

Analysis and evaluation of abnormal noise of air conditioning system for an electric vehicle

Intermittent booming occurs in the air conditioning system of an electric logistics vehicle, which seriously affects the riding comfort. First of all, the noise source (electric compressor) and the main transmission path (mounting bracket) are quickly located by means of separate operation, try-out method and spectrum analysis. Then, by the modal analysis, CAE simulation and other technical means, it is confirmed that booming is the structural noise generated during the process where the vibration excitation of the electric compressor is amplified by the resonance and transmitted to the body through the mounting bracket to cause the resonance of the thin-wall sheet metal. And then, the source, transmission path and response of booming are analyzed one by one, and two improvements of the transmission path are proposed and tested. Finally, the objective parameters and the psychoacoustic annoyance are used to evaluate and analyze the interior sound quality before and after improvement. The results show that the improved transmission path can quickly and effectively solve the booming problem caused by the air conditioning system, and the maximum booming noise can be reduced by 19 dB(A), the psychoacoustic annoyance can be reduced by 72.1%.