Plug-in hybrid electric vehicles (PHEVs) are promising options for future transportation. Having two sources of energy enables them to offer better fuel economy and fewer emissions. Significant research has been done to take advantage of future route information to enhance vehicle performance. In this paper, an ecological adaptive cruise controller (Eco-ACC) is used to improve both fuel economy and safety of the Toyota Prius Plug-in Hybrid. Recently, an emerging trend in the research has been to improve the adaptive cruise controller. However, the majority of research to date has focused on driving safety, and only rare reports in the literature substantiate the applicability of such systems for PHEVs. Here, we demonstrate that using an Eco-ACC system can simultaneously improve total energy costs and vehicle safety. The developed controller is equipped with an onboard sensor that captures upcoming trip data to optimally adjust the speed of PHEVs. The nonlinear model predictive control technique (NMPC) is used to optimally control vehicle speed. To prepare the NMPC controller for real-time applications, a fast and efficient control-oriented model is developed. The authenticity of the model is validated using a high-fidelity Autonomie-based model. To evaluate the designed controller, the global optimum solution for cruise control problem is found using Pontryagin's minimum principle (PMP). To explore the efficacy of the controller, PID and linear MPC controllers are also applied to the same problem. Simulations are conducted for different driving scenarios such as driving over a hill and car following. These simulations demonstrate that NMPC improves the total energy cost up to 19%.
Index Terms-Ecological adaptive cruise controller, intelligent transportation systems, advanced driving assistant systems, nonlinear model predictive controller.
ManuscriptMahyar Vajedi received the B.Sc. and M.Sc. degrees in mechanical engineering from Sharif University of Technology, Tehran, Iran. He is currently working toward the Ph.D. degree with the Department of Systems Design Engineering, University of Waterloo. He is the author of several published papers. His research interests include intelligent vehicle control systems, such as eco-cruise controllers, adaptive cruise controllers, and intelligent energy management systems for electric propulsion vehicles. Nasser L. Azad is currently an Assistant Professor with the Department of Systems Design Engineering, University of Waterloo. His research program operates at the intersection of advanced vehicle electrification and vehicle communication technologies, where he specializes in the development of intelligent automotive controllers that can leverage information provided by emerging ITS, GPS, GIS, and advanced wireless technologies to optimize key performance characteristics, such as fuel economy and emission reduction, in real time. The multidisciplinary nature of his research has allowed him to establish strong collaborative networks with researchers from universities in Europe...