某电动汽车低频压耳问题识别与控制研究

Research on recognition and control of low frequency ear pressure problem of an electric vehicle

为解决某电动汽车车速在40~60 km/h时车内存在明显的“咚咚声”和低频压耳感问题,进行整车主客观试验,发现是由背门一阶模态被路面激励导致车内噪声被放大。针对存在的问题进行背门模态试验,识别出了背门模态参数。根据模态分析理论和动力吸振器原理,对问题进行确认,并设计了1款动力吸振器。对比加装动力吸振器前后车内噪声及背门振动幅值的变化,结果表明:加装动力吸振器后,同样工况下37 Hz附近共振带明显消失,前排噪声峰值降低3 dB(A),后排噪声峰值降低5.6 dB(A),背门振动峰值降低0.05g,主观不适感消失。

In order to solve the problem of obvious “boom” and low-frequency ear pressure in an electric vehicle at 40~60 km/h, a subjective and objective test of the whole vehicle is carried out, and it is found that the first-order mode of the back door is excited by the road surface.The internal noise is amplified.The back door modal test is carried out for the existing problems, and the back door modal parameters are identified.According to the theory of modal analysis and the principle of dynamic vibration absorber, the problem is confirmed, and a dynamic vibration absorber is designed.Comparing the changes in the noise and the vibration amplitude of the back door before and after the installation of the dynamic vibration absorber, the results show that after the installation of the dynamic vibration absorber, the resonance band near 37 Hz under the same working conditions disappears significantly, and the front row noise peak value is reduced by 3 dB(A).The peak rear noise is reduced by 5.6 dB(A), the peak vibration of the back door is reduced by 0.05g, and the subjective discomfort disappears.