Regenerative brake energy analysis for the VTREX plug-in hybrid electric vehicle

The market sector of hybrid-electric and full function electric vehicles is growing within the automotive transportation sector. This paper will focus on understanding the gains of regenerative braking and the associated energy losses. The energy equations for tractive effort at the wheels can be resolved into propelling, braking, and idle. For this study, the braking section of a drive cycle will be the primary focus. Regenerative braking allows the vehicle to recoup some of the energy that would be lost to friction brakes by using the motor as a generator. The energy recovery and losses of regen braking will be explained with the impacts on range, and supplying accessory loads. This study will focus on validating the model against the Virginia Tech Range Extended Crossover (VT_REX) that was built to compete in EcoCAR: the NeXt Challenge.