Evaluation of Objective Sound Quality in Electric Drive System with Multi-power Levels and Full-Operational Conditions

In electric vehicles (EVs), the ear-piercing acoustic noise contributed by the electric drive systems (EDSs) has become a critical issue in sensitive situations. This paper provides a comprehensive sound quality evaluation associated with objective psychological parameters in EDSs with multi-power levels and full-operational conditions. The experimental test sets, prototype categories and acoustic samples are firstly proposed to reveal the sound pressure level distributions. Then, the objective psychological parameters are introduced and divided into six dimensions. The principal component analysis (PCA) method has been employed to achieve dimensionality reduction, in which the original six dimensions can be reduced to two dimensions. The calculated and evaluated results show that the loudness and sharpness are the main contributing components with a cumulative contribution of 99.93%. All results are sensitive to the operational conditions. The proposed work and the related results can be seen as guidance for comfort requirements, as well as NVH design, in EV applications.