Full Description

This SAE Recommended Practice SAE J2847-2 establishes requirements and specifications for communication between Plug-in Electric Vehicle (PEV) and the DC Off-board charger. Where relevant, this document notes, but does not formally specify, interactions between the vehicle and vehicle operator.

This document applies to the off-board DC charger for conductive charging, which supplies DC current to the Rechargable Energy Storage System (RESS) of the electric vehicle through a SAE J1772 coupler. Communications will be on the SAE J1772 Pilot line for PLC communication. The details of PowerLine Communications (PLC) are found in SAE J2931/4.

The specification supports DC energy transfer via Forward Power Flow (FPF) from source to vehicle.

SAE has published multiple documents relating to PEV and vehicle-to-grid interfaces. The various document series are listed below, with a brief explanation of each.

Figure 1.1 shows the sequencing of these documents and their primary function (e.g., the J2836 and J2847/1 documents start with Smart Charging, J2836 and J2847/2 then adds DC charging, etc.). The intent is to have subsequent slash sheets complement each other as more functions and features are included. The /6 series of documents add wireless charging items not already included in the proceeding slash sheets. These are all then included in Interoperability in SAE J2953 and security in SAE J2931/7. J3072 then includes the PEV to grid requirements for Vehicle to Grid (V2G) power and communication to match J2836/3 Use Cases.

The summary of documents for DC Charging is then as follows:

SAE J1772 is the PEV to EVSE systems document and includes the system and timing diagrams for DC Charging

SAE J2836/2 starts with the Use Cases for DC Charging communications

SAE J2847/2 then transforms these Use Case requirements into the signals and messages

SAE J2931/1 is where the Protocol requirements are placed for all PEV communications

SAE J2931/4 is used for the PLC communication requirements for DC Charging since it is only a wired median

SAE J2953/1 is the Interoperability requirements

SAE J2953/2 is the Interoperability procedure and plan

SAE J2931/7 includes the security