Noise evaluation method of DC motor according to change of load

: M otor noise is a major concern in order to improve perceptual feeling of car interior sound due to increased motor usage in passenger cars. The purpose of this study is to propose factors that can represent the acoustic performance of motor noise according to the change of load. To this end, at first, it is shown that power spectrum and total loudness are not fit for noise performance, and then,   , partial loudness related to the brush friction component, and   , partial loudness related to the torque ripple component are investigated as factors representing motor noise. The performance curve of motor noise using   and   is proposed to identify trends of motor noise according to the loads. The curve could be a guide for the noise control, the selection of motor, and the improvement of a system.