Fuel Efficient Speed Optimization for Real-World Highway Cruising

Conference · Tue Apr 03 04:00:00 EDT 2018

DOI:https://doi.org/10.4271/2018-01-0589· OSTI ID:1482390

Shen, Daliang; Karbowski, Dominik; Rousseau, Aymeric

This paper introduces an eco-driving highway cruising algorithm based on optimal control theory that is applied to a conventionally-powered connected and automated vehicle. Thanks to connectivity to the cloud and/or to infrastructure, speed limit and slope along the future route can be known with accuracy. This can in turn be used to compute the control variable trajectory that will minimize energy consumption without significantly impacting travel time. Automated driving is necessary to the implementation of this concept, because the chosen control variables (e.g., torque and gear) impact vehicle speed. An optimal control problem is built up where quadratic models are used for the powertrain. The optimization is solved by applying Pontryagin’s minimum principle, which reduces the problem to the minimization of a cost function with parameters called co-states. The proposed algorithm assumes piecewise constant slopes and speed limits, and it solves the transition vehicle speeds for each junction of such segments. In addition, a method to extract route information from digital maps is presented, which complies with the proposed optimization algorithm. The algorithms are evaluated in simulation, using Autonomie, a simulation tool for vehicle energy consumption modeling. The optimal control trajectory (e.g., torque, gear) is first computed offline. It is then applied in an open-loop fashion in online simulation, using a forward-looking model of the vehicle in Autonomie. Simulation results show over 8% fuel saving for two selected real-world routes.

• Research Organization: Argonne National Laboratory (ANL)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE) - Office of Vehicle Technology
• DOE Contract Number: AC02-06CH11357
• OSTI ID: 1482390
• Country of Publication: United States
• Language: English

Related Subjects

Simulation and modeling
Optimization
Vehicle networking
Energy consumption