Analysis and Optimization of Abnormal Noise of Commercial Electric Drive Axle

NVH (Noise, Vibration and Harshness) of the electric drive axle (EDA) is a key attribute in electric-vehicle development. The NVH attributes of the EDA directly determines the driving comfort and customer feeling of the vehicle. Especially in pure electric working condition, the EDA noise is more perceptible by people without the engine noise masking. This paper investigates the abnormal noise in the vehicle caused by EDA. First, the filtered playback method is used to identify abnormal noise frequency between 330Hz and 430Hz.Adopted modal analysis, MASTA simulation, modulation noise analysis to identify problematic critical parts. The validity of the results is verified using the DOE method by part exchange, and finally locked to the source of gear parameters Rs and Fr. By adjusting the production process of gear and the second shaft, the assembly process error was avoided, and the gear parameter targets are formulated. The verification results of the whole vehicle assembly of small batch EDA showed that the optimized production process reduced the vibration and the interior noise of the EDA, and effectively optimized the abnormal noise problem of the EDA of commercial vehicles. The diagnostic ideas, test methods and optimization schemes for the abnormal noise of the EDA in this paper have important reference significance and value for the design of electric drive systems for passenger cars and commercial vehicles.