Research On Ride And Safety Performance Of In-wheel Motor Drive EV

The Research and Development Department of all automakers in the world arecommitted to an ultimate goal—to realize the electrification of vehicles. The reasonis that Electric Vehicles (EV) have distinct advantages over traditional ones in termsof energy conservation and environment protection. But in-wheel motor driveelectric vehicles are driven by in-wheel motors which are installed directly on thewheels, giving rise to a significant change in the unsprung mass, thus severelyaffecting the performance and safety. This paper is a systematic analysis and studyon this problem.It begins with a simple introduction to the in-wheel motor drive ElectricVehicles and its literature review both at home and abroad, which is then followedby an introduction to ride performance. This study models a vehicle with thesoftware ADAMS, conducts a stimulation analysis of ride performance and safety,and analyses the different effects on ride performance and safety with differentunsprung mass. It is found that the increase of unsprung mass has little effect on theacceleration of sprung mass and the dynamic deflection rate of suspension, but muchon the dynamic load of tire.In order to reduce the effect that the change of unsprung mass has on thedynamic load of tire, this study, adopting the theories of sliding mode control andfractional calculus, designs the semi-active suspension control strategy to controlthe dynamic load of tire. Meanwhile, it proposes the fractional order hybrid dampingcontrol strategy based on Sky-hook and Ground-hook. In addition, it also designs thefractional order sliding mode control algorithm based on an ideal model reference ofa hybrid damping control strategy based on Sky-hook and Ground-hook and adoptsthe fractional order exponential approach law so as to obtain better model trackingresults. And then, co-simulation experiments are conducted based on ADAMS andMATLAB/SIMULINK, and the simulation result indicates that, compared withconventional suspension system: the semi-active suspension system employing thefractional order hybrid damping control strategy based on Sky-hook andGround-hook can well control the dynamic load of tire but has an adverse effect onthe vibration acceleration of sprung mass; while the semi-active suspension systemadopting the fractional order sliding mode control algorithm which is based on anideal model reference of a hybrid damping control strategy based on Sky-hook andGround-hook can not only control the dynamic load of tire but also have good rideperformance.