Several 22 kW charging stations by the manufacturer Webasto have been installed on the company parking lots of Robotron and its subsidiary SASKIA Informations-Systeme GmbH within this project. These stations have been successfully connected to the infrastructure of the smart metering system. The smart meter gateway and the PPC CLS gateway serving as the control unit, with integrated "Robotron Communication Server on Edge" (RCSoE) software, are used for communication with the back-end infrastructure. The software handles bidirectional communication between the charging station and the backend systems, thus enabling intelligent grid control.
Use of multiple communication protocols
Dr. Christian Hofmann, Head of the Metering Department at Robotron, explains: "The biggest challenge in charging management is that many wallboxes do not understand the communication protocols of the smart meter gateway. Therefore, an additional translation protocol is needed to connect the two worlds. To demonstrate different scenarios, the installed charging stations were connected with two different protocols."
Besides the widely used "Open Charge Point Protocol" (OCPP) standard, the "Modbus TCP" protocol is also used." In both cases, the RCSoE application on the PPC CLS gateway handles protocol forwarding, enabling direct, bidirectional and secure communication between the charging station and the backend system of the charging station operator. The aEMT system is able to mirror the behavior of the charging station, so that no adjustments are necessary in Webasto's backend system.
Ingo Schönberg, CEO of PPC, says: "In this project, we were able to successfully demonstrate the feasibility of intelligent charging management via the smart meter gateway using various protocols. The end-to-end communication between charging station and charging management backend is already possible to implement "out-of-the-box" today. We are looking forward to driving climate protection through efficient grid integration of eMobility in this way."
Dynamic grid control and energy management
The charging management solution enables dynamic switching as a basic requirement for integrating electromobility into the grids in a way that is both grid-serving and consumer-friendly. Control processes can be automated on the basis of defined threshold values thanks to intelligent protocols and interfaces. This makes it possible to implement energy management on the basis of dynamic electricity tariffs, grid-serving management by the distribution system operator, and trading of the flexibility of electromobility on the electricity market.
The solution offers providers of charging infrastructure in particular a simple and compatible way of mapping the regulatory requirement. Karl Kolmsee, Head of Product Portfolio Management Energy Solutions in the Customized Solutions division at Webasto, comments: "The implementation shows that a clever combination of standards from the automotive and energy industries can create added value for everyone, using protocols that are already established today. Furthermore, existing installations can be opened up for new services."
What makes the implemented solution special is the combination of currently available standard technologies from smart metering and electromobility without any additional development effort. Existing charging technology can be securely accessed via the smart meter gateway for flexibility and load management by value-added service providers and network operators in accordance with BSI (Federal Office for Information Security) and BMWi (Federal Ministry for Economic Affairs and Energy) specifications. It also serves as the basis for service offerings to end customers.
