Parametric analysis and compensation of ride comfort for electric drivetrains utilizing in-wheel electric motors

In this paper we study the comfort effects of increased unsprung mass that result from the utilization of in-wheel or wheel-hub mounted electric motors used in hybrid and/or electric drivetrains. For this purpose we reduce the problem to the analysis of the quarter car suspension model to assess how increasing unsprung mass affects the ride comfort. In order to analyse the changes in the ride comfort levels according to the ISO 2631 standard, the study was performed in frequency domain using random road profile inputs generated according to the ISO 8608 standard. Also the results were assessed using commercial multibody vehicle simulation software. Finally we suggest empirical solutions regarding modified suspension and tire parameters to compensate and mitigate the detrimental effects of increased unsprung mass using passive suspension modification.