Vehicle-grid integration is one of the hottest topics in the EV world, with pilot projects cropping up all over the globe. The relationship between EVs and the electrical grid is complex – charging must be managed to avoid overloading local grids, but on the other hand, EVs and/or used EV batteries can help utilities to manage fluctuations associated with renewable energy sources.

To enable the intelligent grid of the future, seamless connectivity will be essential. To address this issue, Fraunhofer ESK is developing underlying communication methods for a uniform energy management system. At the Hannover Trade Fair in April, ESK researchers will demonstrate how a charging station can serve as an interoperable node between an EV and a network control center, using the ISO/IEC 15118 and IEC 61850 standards.

Digital communication before, during and after charging is crucial for vehicle authentication, time-delayed charging and dynamic billing models, and also allows charging station operators to offer customers a range of value-added services. This requirement led to the creation of the ISO/IEC 15118 standard.

“Our experience has shown that charging station manufacturers are still shying away from the standard because the implementation is too complex,” says Dr. Erik Oswald from Fraunhofer ESK. “For this reason, we developed a reference installation that significantly streamlines the implementation.”

As part of the SmartV2G (smart vehicle to grid interface) research project sponsored by the EU, ESK researchers developed an enhancement of the 15118 standard to effect communication between the charging station and the EV. They then tested the interaction of the individual components using the HomePlug Green PHY transmission technology.

To date, energy providers and grid operators have used proprietary protocols to communicate with elements in their networks such as energy sources and end users. With the enhancement and implementation of the IEC 61850 standard, Fraunhofer ESK now offers one standard for communicating with all elements in a network, streamlining energy management systems and enabling the simple and flexible integration of charging stations and EVs into the smart grid.

Source: Fraunhofer ESK