This SAE Information Report, SAE J2931, establishes the requirements for the powerline carrier (PLC) digital communication between plug-in electric vehicles (PEVs), the electric vehicle supply equipment (EVSE) and the utility or service provider, energy services interface (ESI), advanced metering infrastructure (AMI), and home area network (HAN).
This specifies the digital communication protocol stack between PEVs and the EVSE. The purpose of the stack outlined in Figure 1 and defined by layers 3 to 6 of the open systems interconnection (OSI) reference model (Figure 1) is to use the functions of layers 1 and 2 specified in SAE J2931/4 and export the functionalities to layer 7 as specified in SAE J2847/2 (as of August 1, 2012, revision) and SAE J2847/1 (targeting revision at the end of 2012).
Communications between the EVSE and other than PEV entities such as AMI, ESI, HAN, utility head-end, etc., as shown in Figure 2 are outside of the scope of this document. It is presumed that a bridging device will be required to carry PEV information beyond the EVSE and may be collocated with the latter.
The effort continues however, to additional comments and viewpoints, while the task force also continues additional testing and early implementation. Results of this effort will then be incorporated into updates of this document and lead to a republished versions as needed.
The SAE J2931 family of documents has been organized into several “slash” subsections:
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This document, SAE J2931/1, defines architecture and general requirements including association, registration, security, and HAN requirements, as well as mapping to other SAE documents.
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SAE J2931/4 defines the MAC and PHY layer implementation of digital communications using BB OFDM and either the SAE J1772 pilot wire or mains.
Testing and validation of the aforementioned physical layer specifications is ongoing, and it is possible that the results of said testing may preclude one or more of the proposed solutions as unable to meet the technical requirements. Reduction of the available options to a single, worldwide standard remains the long-term goal.
The document mapping of the PEV communication standards are further defined in Section 5.