An intelligent network for fast charging of electric vehicles

"Today, the electric vehicle appears to be the miracle solution for just about everything: reducing greenhouse gas emissions, improving air quality, reducing urban noise pollution and cutting travel costs. However, two major challenges to battery recharging are holding back its development: speed and energy management for a fleet of recharging systems.

Supported by the French Environment and Energy Management Agency (ADEME), the VELCRI (Véhicule Électrique à Charge Rapide Intégrée) project has developed and tested a car and a charging station for ultra-fast global recharging (5 to 15 minutes). The researchers have also developed a system which, by means of a connection to the vehicle, ensures that the electrical network can withstand this demand.

Intelligent networks to manage battery charging

The development of asmartgrid connecting vehicle and energy supplier enables the management of an electrical distribution network that includes both consumption and production. Vehicle batteries can be used for micro-storage of energy, for example as emergency generators for the home. By forecasting electricity consumption, the network will be able to avoid overloads or dips in consumption, notably by balancing supply and demand in real time through appropriate pricing, adjustment mechanisms and electricity storage facilities. Eventually, the smart grid will also enable renewable energies to be favored for car charging.

Secure communication via Android app

All this requires the use of sensors to collect data, and raises the issue of "digital privacy". "If this data is public, anyone can see when you're at home by tracking electricity consumption. If it's only available to the operator, he'll want to exploit it in one way or another", explains Hossam Afifi, a researcher at Télécom SudParis. Faced with the need for an anonymizing intermediary, his team has developed an Android application, ensuring secure communication between the user's car, the charging station and the electricity network.

The application automatically detects the VELCRI network, enabling access to the charging system manager. Customers authenticate themselves via personalized profiles, then the application connects them to a remote server containing the types of electric recharges corresponding to the vehicles, as well as other services. It also manages the recharging process and verifies the energy transmitted to the battery via successive acknowledgements every 1kW charged, to ensure that recharging proceeds correctly. Finally, the application retrieves information on the state of the vehicle's battery in real time and makes it available to the user.

To develop these innovations, Hossam Afifi and his team in the "Réseaux et Services de Télécommunications" (RST) department drew on a number of studies carried out by researchers in the SAMOVAR laboratory, jointly run by Télécom SudParis and CNRS, to optimize energy consumption in networks. In particular, they have defined protocols for increasing the lifetime of wireless mesh sensor networks (MDSAP) or transmitting more data (CEB-P and MSEB-P). In the field of cellular networks, R3S has proposed several mechanisms, linked to signaling between multi-operator base stations and dynamic selection of radio interfaces, for switching traffic between operators and putting under-used base stations to sleep, without interruption or loss of quality of service for the user.

Our partners

Led by Renault, the VELCRI project brings together Schneider Electric, Saft, EDF, VALEO, Radiall, CEA-Ines, CNRS-Pprime, EURECOM, Apojée, CNRS and Télécom SudParis.