Design, modeling, and research on vertical performance of a drive system with in-wheel motor as dynamic vibration absorber

There are many advantages to an in-wheel motor drive (IWMD) vehicle. However, installing the motor in the wheel will increase the unsprung mass and deteriorate the vehicle ride comfort. In this paper, this conclusion is verified by a comparative simulation test of ride comfort. To solve the above problems, this paper puts forward a new in-wheel motor drive (NIWMD) model and comprehensively evaluates the vertical performance of the vehicle from two aspects: vehicle ride comfort and motor vibration. The vertical performance evaluation indexes include body acceleration, wheel dynamic load, suspension dynamic deflection, motor acceleration, and motor relative displacement. The vertical performance of the NIWMD model, CMD model, and IWMD model is compared. The results show that, especially in the high-frequency resonance region, the NIWMD model can effectively suppress the peak vibration response and improve the vehicle vertical performance. The influence of system parameters of the NIWMD model is studied, and the sensitivity of system parameters is calculated. The research results show the parameters that have a great influence on the vehicle vertical performance, which points out the direction for the optimization of the vertical performance of the NIWMD model.