NVH Design Criterion of Electric Powertrain Mounts

Compared with the mechanical and combustion noise of low-frequency firing orders of an internal combustion engine, the electric drive assembly noise of electric vehicles is mainly the high-frequency whining noise generated by electromagnetic forces and transmission gear meshing. Although the radiated sound power is far less than that of an internal combustion engine, the high frequency noise of the electric motor and the transmission is much annoying. Noise below 2000–2500 Hz generated by an electric drive assembly in a vehicle passenger compartment is mainly contributed by structural transfer paths. Due to the high torque of the electric drive motor of electric vehicles, it is a challenge to achieve better mount isolation performance at the same time when the anti-torque performance of the electric drive assembly mounting system is realized. In this paper, by comparing the vibration characteristics of electric vehicles and traditional ICE vehicles, comparing different mount layout schemes, and analyzing the main factors affecting the vibration isolation rate of the electric drive assembly mounting system, the general design principles of the electric drive assembly mounting system are summarized to achieve balanced attribute performance.