Electric vehicle platform for drivability analysis

In order to lead properly an electric vehicle project, it is very important to assess and optimize the driver perception during manoeuvres such as tip-in and tip-out. This aspect of vehicle customer perception is called “drivability”. To meet these objectives, a co-simulation platform has been developed between models under LMS-AMESim^® and Matlab/Simulink^®. The first model represents the physical characteristics of the vehicle with LMS-AMESim^® and takes into account stiffness of the driveline, motor block behaviour onto its mounting blocks, suspensions, tires and vehicle dynamics. The second model computes the torque command of the electric motor for drivability manoeuvres as well as for driving cycles with Matlab/Simulink^®. This paper shows how this platform can help integration teams to tune software and hardware parameters from the early steps of the project's design. Concerning the software, any torque setpoint strategy can be integrated in order to filter the shocks amplitude during tip-in. The impact of an RST filter on the vehicle response is studied; moreover, this study shows that the vehicle range can be added to classical optimization criteria such as time response and overshoot. For the hardware side of this platform, the very good correlation of the model's acceleration with track tests gives a high level of trust in the sensitivity study of most influents parameters on the drivability rating, which is assessed by some objectives criteria on vehicle acceleration.