This SAE Recommended Practice 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.
This document 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 shows the sequencing of these documents and their primary function (e.g., the SAE J2836 and SAE J2847/1 documents start with smart charging, SAE J2836 and SAE 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. SAE J3072 then includes the PEV to grid requirements for vehicle-to-grid (V2G) power and communication to match SAE J2836/3 use cases.
The summary of documents for DC charging is then as follows:
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SAE J1772 is the PEV to EVSE systems document and includes the system and timing diagrams for DC charging.
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SAE J2836/2 starts with the use cases for DC charging communications.
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SAE J2847/2 then transforms these use case requirements into the signals and messages.
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SAE J2931/1 is where the protocol requirements are placed for all PEV communications.
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SAE J2931/4 is used for the PLC communication requirements for DC charging since it is only a wired median.
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SAE J2953/1 is the interoperability requirements.
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SAE J2953/2 is the interoperability procedure and plan.
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SAE J2931/7 includes the security.