Role of Regenerative Braking in Velocity Trajectory Optimization of Electrified Powertrains over varying Road Grades

Eco-driving via velocity trajectory optimization and regenerative braking can both reduce the energy demand of an electric vehicle (EV). However, eco-driving can save more energy than can be recovered via regenerative braking due to the total roundtrip efficiency of the motor/generator. The optimal velocity trajectory would always avoid braking if the constraints allow. This paper investigates energy optimal velocity profiles for various electric ground vehicles over varying road grades, where the autonomous vehicles can adjust their velocity trajectory. The optimal velocity trajectories, numerically obtained from Dynamic Programming, significantly reduce the total energy demand by the motor compared to a constant cruising operation for the same travel distance and time. The optimized velocity trajectories, thus increase vehicle range without a change in battery size or trip time.

[1]  Sean R Eddy,et al.  What is dynamic programming? , 2004, Nature Biotechnology.

[2]  Chen Zhang,et al.  Route Preview in Energy Management of Plug-in Hybrid Vehicles , 2012, IEEE Transactions on Control Systems Technology.

[3]  Olle Sundström,et al.  A generic dynamic programming Matlab function , 2009, 2009 IEEE Control Applications, (CCA) & Intelligent Control, (ISIC).

[4]  E. Nam,et al.  Development of Advanced Light-Duty Powertrain and Hybrid Analysis Tool , 2013 .

[5]  Erik Hellström,et al.  Look-ahead control for heavy trucks to minimize trip time and fuel consumption , 2007 .

[6]  Mehrdad Ehsani,et al.  Investigation of the Effectiveness of Regenerative Braking for EV and HEV , 1999 .

[7]  Wissam Dib,et al.  Optimal energy management for an electric vehicle in eco-driving applications , 2014 .

[8]  A. B. Schwarzkopf,et al.  Control of highway vehicles for minimum fuel consumption over varying terrain , 1977 .

[9]  Edward K. Nam,et al.  Modeling and Validation of Power-Split and P2 Parallel Hybrid Electric Vehicles , 2013 .

[10]  Ilya V. Kolmanovsky,et al.  Optimally controlling Hybrid Electric Vehicles using path forecasting , 2009, 2009 American Control Conference.

[11]  Lorenzo Serrao,et al.  Optimal control to minimize trip time and energy consumption in electric vehicles , 2011, 2011 IEEE Vehicle Power and Propulsion Conference.

[12]  Yang Bin,et al.  Multi-information integrated trip specific optimal power management for plug-in hybrid electric vehicles , 2009, 2009 American Control Conference.

[13]  Dimitar Filev,et al.  Analytical Solution to the Minimum Energy Consumption Based Velocity Profile Optimization Problem With Variable Road Grade , 2014 .

[14]  Raymond G Fontaine,et al.  Vehicle Test Facilities at Aberdeen Test Center and Yuma Test Center , 2017 .