TwinCAT 3 IoT OCPP combined with the EL6761 EtherCAT Terminal

A complete solution for communication with the charging infrastructure and electric vehicles

Beckhoff has added the Open Charge Point Protocol (OCPP) to the TwinCAT IoT product portfolio based on the WebSocket protocol which has recently been introduced for the IoT driver. OCPP standardizes the communication between charging stations for electric vehicles and the associated central management systems. This is combined with the new EL6761 EtherCAT Terminal, which serves as a communication interface in accordance with IEC 61851 and ISO 15118, to create a universal solution for charging infrastructure communication.

With the new function TwinCAT 3 IoT OCPP (TF6771), OCPP was implemented as a C++ driver with the associated PLC library as a wrapper. Due to their high market relevance, OCPP versions 1.6 and 2.0.1 are being implemented first. The focus is on the following two use cases:

TwinCAT is used as a controller for a charging station together with the new EL6761 EtherCAT Terminal, and is then connected to the central management system as an OCPP client.
When connecting other charging stations via the OCPP protocol, TwinCAT represents part of the central management system, e.g., to enable local load management of a charging station network. In parallel, TwinCAT can be connected to another management system, e.g., to implement authentication or billing mechanisms.

The EL6761 1-channel communication interface also offers two options: the EtherCAT Terminal can be used to enable communication for the charging infrastructure, directly to the electric vehicle and from it to the higher-level charging management system. Two independent communication standards are supported – PWM communication according to IEC 61851 and powerline communication according to ISO 15118. The latter provides a flexible communication channel to transmit all necessary data between the vehicle and the charging station.