The Analysis And Control Of Electrical Vehicle Interior Noise

As energy issues become increasingly prominent, our country is developing electric vehicle industry. EV(Electric vehicle) has inherent advantages in noisy performance, but that does not mean that designers do not need to do research in this area. Recently the design of EV mainly refer the vehicles of internal combustion engine in structure and parameters or the designing experience, and almost has nothing in noise theory and guidance for electric vehicles. However, the dynamic characteristics and noise characteristics between the motor and internal combustion engines have much difference, so that in some circumstance EV does not have an absolute advantage. So the noisy performance of electric vehicles also need special attention. However, the current EV is not enough emphasized in this area, resulting in EV at this stage is not very ideal in terms of noisy characteristics. Thus, with the industry of EV gradually from the designing stage to mass production stage in China, the analysis and control of noise in EV is particularly urgent and important.In this paper, KK-60EZ electric vehicle is analyzed, and applied finite element analysis, boundary element method and acoustic CAE, and refered domestic and international noisy control methodel of EV, discuss the analysis way to the low frequency noise of EV, and its influence factors and control measures, so as to provide theoretical support for design of reduceing the low frequency noise of the EV, and improve the quality of its interior noise; the other hand, I tried to explore a set of perfect analysis and control way to the low frequency noise inside the EV. The main contents of the article:(1) The finite element model of the white body structure and the acoustic models of the EV cavity were established, and their structural and acoustic modal analysis were carried out, and the modal frequency of each order and mode shapes are described,and it provided basis for the later noisy control.(2) The source of the vibration and noise sources of EV are summed up, and analysis the acoustic response of EV in the stimulation of vibration of the motor and road, find out the changed characteristics of noise level in the right ear of the driver and rear passenger as the vibration frequency; and Analysed the acoustic contribution of the body panel to the main field point; and provied the significance for the control by improving the structure.(3) The transfer of noise in cavity is analyzed, based on studies and results of various theories above, I proposed a variety of controlling way to different noise and vibration, and carried out some appropriate changes to the body structure to reduce noise and vibration of EV,and do the simulation for the improved cavity noise, and got good results.