Cooperative Eco-driving Controller for Battery Electric Vehicle Platooning

Abstract

Eco-driving and platooning both play an increasingly important role in alleviating range anxiety for battery electric vehicles (BEVs). Pontryagin's Minimum Principle (PMP) has been popularly adopted for designing eco-driving speed planners because of its capability to achieve near optimal solutions at high computational efficiency that brings potential of real-time implementation. However, most of the existing PMP-based eco-driving studies did not consider the change of aerodynamic drag coefficient due to platooning effect, or simply ignore the nonlinear aerodynamic resistance to achieve analytical optimal solutions. Such simplification of aerodynamic resistance model can lead to inaccuracy in vehicle speed optimization, and thus potentially make eco-driving less energy-efficient and cause severe safety issues in car following scenario. In recognition of these issues, this paper proposes an innovative PMP-based cooperative eco-driving controller (CEDC) that incorporates the impact of air drag coefficient change in the optimal speed trajectory design for the circumstance of two-BEV operation. The simulation results reveal noticeable differences in optimal speed profile, when compared to baseline CEDC controller which adopts a constant aerodynamic drag coefficient. It is also shown that implementation of the optimal speed profile from baseline CEDC controller will violate safety constraint and lead to collision. Furthermore, the simulation results demonstrate that, the CEDC can reduce energy consumption by 12.25% and 4.68%, respectively, when compared to intelligent driver model (IDM)-based control and the baseline CEDC.