Cao, Y., Zhao, T., Li, C., Yang, M. et al., "Exterior Noise Source Identification and Contribution Analyses for Electric Vehicles," SAE Technical Paper 2016-01-1324, 2016, doi:10.4271/2016-01-1324.
The primary noise sources of electric vehicles differ from that of traditional vehicles due to the fundamental differences in their powertrain architecture. In this work, some exterior noise test methods for electric vehicles are briefly introduced first, which include a pass-by noise measurement method during acceleration on the proving ground as well as a similar measurement in a semi-anechoic room. The obtained results based on those two methods from a production electric vehicle are compared and analyzed. Then the mechanism of the source, path, and contribution is illustrated, and a model of path-source-contribution for electric vehicles is established. The model validation is subsequently carried out by correlating the calculated outcomes with the measured results under real operating conditions. Finally, by using the model, contribution analyses are carried out to identify the primary exterior noise sources. The result shows that the tire noise is the most contributing exterior noise source for electric vehicles during acceleration, while the radiated noise from the motor is not a major contributor.