Improvement of Regenerative Braking Energy of Fully Battery Electric Vehicle Through Optimal Driving

Though a fully battery electric vehicle serves zero air pollution, people are not getting interest to adopt it. The primary reason is the low driving range of battery electric vehicle. A unique advantage of electric vehicle is to easily implement regenerative braking which converts the lost kinetic energy during braking to electrical energy that can recharge the battery, thereby extending the electric vehicle range. In order to maximize the range extension, maximum braking energy needs to be regenerated. Through past studies, it was noticed that driving harshness lowers the regenerative efficiency in a great extent. Based on this understanding, in the present work, an analysis is carried out to enumerate the improvement nature of regenerative braking energy of fully electrical vehicle through adopting an optimal driving strategy. Regenerative braking energy based on optimal driving strategy is compared with that of using arbitrary driving strategy to examine its effectiveness in different speed changes. The present analysis is carried out using a typical fully battery electric vehicle with serial regenerative braking system. Simulation results suggest that use of multiple deceleration rates during braking is most appropriate. The same concept was found valid after analysing published experimental drive data of an electric bus. A significant regenerative braking energy improvement was noticed particularly when the speed changes is high.