Dynamic modeling and experimental verification of electric-drive axle considering real gear mesh misalignment

The electric-drive axle is a complex flexible system, where loaded deformation inevitably leads to gear mesh misalignment and affects the dynamic response. Previous studies usually study the object of a single gear or gear mesh misalignment values are assumed, which cannot reflect the real working condition of the gear. In this study, the dynamics of a complex flexible system based on an electric-drive axle were modeled considering real gear meshing misalignment excitation. A nonlinear loaded static model of the gear-shaft-bearing-housing system was established to obtain the real gear mesh misalignment. Loaded tooth contact analysis was then applied to calculate the real transmission error for each gear pair. Finally, a numerical computational dynamic model of the electric-drive axle incorporating real gear mesh misalignment and electromagnetic force was established. Numerical calculations suggested that the misalignment significantly affects the system transmission error, load sharing ratio, and acceleration response. Compared with the results of the bench test, the trends of the housing acceleration response considering the misalignment were nearly consistent, and the maximum relative error of the first-order acceleration amplitude of the planetary gear was 22.08%, which validates the proposed method and proves the necessity to consider the misalignment.