Effects of lightweight gear blank on noise, vibration and harshness for electric drive system in electric vehicles

Abstract

In this paper, effects of lightweight gear blank on static and dynamic behavior for electric drive system in electric vehicles are studied. First, a hybrid finite element-analytical method is proposed in this paper to establish gear load contact analysis model considering the structure of lightweight gear blank, which can balance the computing speed and numerical accuracy. Second, this paper establishes a rigid-flexible coupled dynamic model of electric drive system considering shaft elasticity, bearing stiffness, and housing flexibility. Finally, aiming at the noise, vibration, and harshness problem of an electric drive system equipped on electric vehicles, effects of gear web and gear rim thickness on noise, vibration, and harshness excitation source such as static transmission error and dynamic meshing force as well as dynamic response at bearings and housing are analyzed. The results show that changing gear web and gear rim thickness can significantly reduce dynamic meshing force and dynamic response. Compared with solid gear, dynamic meshing force is reduced by 68.50%, and dynamic response is reduced by 66.70% after optimization, thereby significantly improving the noise, vibration, and harshness performance of gear transmission system in electric vehicles.