Contribution of acoustic harmonics to sound quality of pure electric powertrains

A novel method based on contribution estimation for sound quality evaluation and improvement of electric powertrain is presented in this study. Firstly, the noise samples of an electric powertrain for electric vehicles are collected in a semi‐anechoic chamber. Then the subjective evaluation of an electric powertrain is conducted. Through the correlation analysis between the acoustic energy of powertrain noise in each frequency band and subjective perception, the sensitive frequency ranges of electric powertrain noise which human hearing is susceptible to are determined. Subsequently, the acoustic harmonics of electric powertrain noise in sensitive frequency are distinguished by order tracking. After that, the contribution of sensitive harmonics to both psycho‐acoustical parameters and subjective perception is estimated. Finally, the gear train model for optimisation of gear tooth micro‐geometry is built to improve the sound quality of electric powertrain. The results of psycho‐acoustical parameters and subjective rating of acoustic noise radiated by electric powertain after optimisation show that it is possible for the electric powertrain to improve the sound quality.