Cooperative Control of Connected-Autonomous Electric Buses With Tradeoffs Between Energy Saving and Mobility

Journal article, 2024

— Due to limited mileage and high schedule constraints, electric buses need to maximize not only energy efficiency but also mobility flexibility, especially in lanes where multiple bus lines merge. Connected-autonomous electric buses (CAEBs) indeed reduce inter-vehicle gaps to minimize the impact of bus stops on road capacity, but lead to frequent acceleration and deceleration to ensure safety. Therefore, this paper regards the CAEBs in the merged lane of bus lines as a whole platoon to study the cooperative control algorithm aiming at the tradeoff between energy saving and mobility. Model predictive control and optimal control are combined to design CAEB control inputs where saturation inputs, safe inter-vehicle spacing constraints, and external disturbances are integrated. This paper finds sufficient conditions for the unique solution of the non-convex optimization objective caused by the higher-order energy terms. In addition, this paper proves the semi-negative characterization of the symmetry matrix of higher-order energy terms to realize the asymptotic stability of CAEB platoons. Comparative simulations show that the cooperative control algorithm effectively trades off mobility and energy consumption even in emergency scenarios, and achieves a 25% reduction in energy consumption with only a 2.2% reduction in mobility.