电动汽车低频轰鸣声故障诊断与改进

Fault Diagnosis and Optimization of Low Frequency Booming Noise for Electric Vehicle

针对某电动汽车低频轰鸣声问题进行诊断与改进。首先,基于整车及单品台架声振测试,运用阶次分析、传递路径分析及数值模拟等方法对故障车和零部件进行诊断分析,确认车内轰鸣声为压缩机1阶振动激励经安装支架传递至车身致使薄壁钣金结构共振所产生;其次,按照源、路径和响应的噪声振动控制思路逐一分析,并基于工程化需求确定传递路径为优选改善方向;最后,提出2种增加安装支架隔振量的技术方案进行实车验证,确认了方案的有效性。研究结果表明,改善传递路径可有效降低该车零部件振动导致的车内轰鸣声,噪声总值降低可达11.9 dB(A),为解决同类问题提供了新思路。

Diagnosis and troubleshooting are proceeded for the low-frequency booming of an electric car.The noise and vibration of the vehicle and its parts are tested.The fault car and parts are analyzed based on order analysis,transfer path analysis,numerical simulation and other methods,and it is confirmed that the booming noise is generated through the process in which the first order vibration of the compressor is transmitted to the body through the mounting bracket to cause the resonance of the thin-wall sheet metal structure.According to the noise and vibration control idea of source-path-response,analyzing one by one,the transfer path is confirmed to be the optimal improvement direction based on the engineering needs.Two technical schemes to increase the vibration isolation of the mounting bracket are proposed,and the effectiveness is verified on the vehicle.The research shows that the improvement of the transfer path can effectively reduce the booming noise caused by the vibration of the parts,and the total noise can be reduced by 11.9 dB(A),which provides a new idea for solving similar problems.