Eco-driving for electric vehicles

Eco-driving is an integral component in the reduction of a vehicle's energy consumption. Tools are emerging to help motorists drive safely and use relatively little energy. These tools range from relatively intuitive driver assistance devices (aimed at reducing driving aggressiveness) to tools based on information and communication technologies (GPS, sensors thatdetect other vehicles, communication with a centralized facility, etc.).

Antonio Sciarretta Expert Hybrid Vehicles Control antonio.sciarretta@ifpen.fr	Philippe Moulin Technology, Computer Science, and Applied Mathematics Division philippe.moulin@ifpen.fr

Having access to this information makes it possible to estimate the journey to be made in the immediate future and the associated constraints (distance, average and maximum speed, traffic, etc.). Calculation of the driving profile that minimizes energy consumption in these conditions is then systematically possible using optimal control methods.

Real speed profile measured and optimized with the same distance and speed constraints.

With respect to the first existing applications, IFPEN is rather interested in employing this optimized approach in real urban use. To do this, IFPEN is working with VULog (a specialist in onboard algorithmics and electronics for car-sharing) and Le2i laboratory of the Arts et Métiers. The VME (Ville, Mobilité, Énergie or Town, Mobility, Energy) project, funded by Ademe, involves a fleet of Moebius self-service electric vehicles in Rueil-Malmaison.

The vehicles are fitted with an Onboard Energy Supervisor, which supplies the driver with energyefficient driving advice based on GPS location, detailed maps of the town and online optimization calculations.

A preliminary study conducted with the support of VULog, demonstrated that the range of the vehicles can be 20% more than that measured in real driving conditions. These results are calculated by formalizing the problem in mathematical terms and using an optimal control technique: dynamic programming. The optimized approach is currently being validated on the Rueil fleet.

From left to right : Antonio Sciarretta, Alexandre Chasse, Wissam Dib and Philippe Moulin with "Moebius", the self-service electric vehicles in Rueil-Malmaison.

Publications

• A. Sciarretta, L. Guzzella, at-Automatisierungstechnik 53 (2005), 244–250

• E. Hellström, M. Ivarsson, J. Aslund, L. Nielsen, Control Engineering Practice, 17 (2009), 245-254

>> See also IFPEN Publications database