Abstract: Powertrain excitation is one of the main sources of vehicle vibration and noise, and the problems associated with it are often characterized by low frequency vibration and booming. In order to diagnosis the problem and solve the low-frequency vibration and booming problems of a vehicle under development, firstly, through the vehicle vibration test and analysis, it is determined that the resonance of the powertrain system due to the irrational mode distribution is the source of the problem. Using the genetic algorithm, the mount system is optimized. According to the engine excitation frequency, the rigid body modes of the powertrain are designed to avoid the frequency, which effectively solves the resonance problem. Finally, the mount system is calibrated for decoupling rate, static equilibrium and limiting working condition, and the vehicle vibration test is carried out to verify the effectiveness of the powertrain mounts optimization design method.

Key words: vibration; diagnosis; powertrain mounts; optimize

摘要： 动力总成工作激励是汽车振动噪声的主要来源之一，与之相关的振动噪声问题常常表 现为低频性和轰鸣性。针对某开发车型出现的低频振动与轰鸣问题开展故障诊断与改进工作， 首先通过整车振动测试与分析，确定动力总成系统由于模态分布不合理而引发共振是故障问 题的根源。采用遗传算法，对悬置系统进行优化设计匹配，根据发动机工作激励频率，对动 力总成刚体模态实现了避频设计，有效解决了共振问题。最后对悬置系统进行了解耦率、静 平衡和极限工况校核，以及整车振动测试，验证了动力总成优化设计方法的有效性。

关键词: 振动；故障诊断；悬置系统；优化