Evaluation of regenerative braking effect for E-REV bus according to characteristic of driving cycle

Jongdai Choi, Jongryeol Jeong, Yeong-il Park, and Suk Won Cha

Abstract

The extended-range electric vehicle (E-REV) is an electric vehicle concept that has a light engine to allow an extended driving range. One of the most important features of these vehicles, based on electricity, is their ability to recover significant amounts of braking energy in a process known as regenerative braking. The more driving motor operates widely as generator, the more braking energy can be absorbed. However, it is not realistic in terms of performance for components. This study proposes three regenerative braking torque maps as the constraints to consider their performance. The results of fuel economy for simulations while applying proposed torque maps are compared with those of simulations without any constraints to evaluate effect of regenerative braking for E-REV bus according to characteristic of driving cycle. The characteristics of driving cycles are analyzed to find relationship between driving cycle and fuel economy. The aggressiveness of the driving cycles shows a linear relationship with regard to the difference in the fuel economy. This result can be used to develop power distribution control strategies with regenerative braking models to improve fuel economy levels.