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Discussion Starter #1
Anyone have technical information on the Bolt's combined charge system - in particular the power line communications protocols. Is there an IEEE standard that the Bolt PLC follows?

Just curious.
 

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It's in IEC 61851-23. If you google "design guide for a combined charging system 02.06.2015", you'll find a PDF that has a good diagram on page 7.
 

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standards.globalspec.com/std/9910722/sae-j2847-2

(Basic hyperlink functionality for the forum is nerfed by unknown post count requirements, sorry)

Standard: SAE J2847-2
(R) COMMUNICATION BETWEEN PLUG-IN VEHICLES AND OFF-BOARD DC CHARGERS

Scope:

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.

SAE J2836™ General Requirements and Use Cases. This document is divided into several sections. SAE J2836/1™ is for Utility/Smart Grid messaging, SAE J2836/2™ is for DC Charge Control, SAE J2836/3™ is for Reverse Energy Flow. SAE J2836/4™ is for Diagnostics. SAE J2836/5™ is for Consumer Requirements and the HAN. SAE J2836/6™ is for Wireless Charging.

SAE J2847 Functional Messaging Requirements. This document defines the functional messages required for a given function. This document is divided into several sections that correspond to SAE J2836 above. SAE J2847/1 is for Utility/Smart Grid messaging, SAE J2847/2 is for DC Charge Control, SAE J2847/3 is for Reverse Energy Flow. SAE J2847/4 is for Diagnostics. SAE J2847/5 is for Consumer Requirements. J2847/6 is for Wireless Charging.

SAE J2931 Digital Communications for PEVs. This series of documents defines the requirements to enable digital communications for PEVs. It is divided into several sections. J2931/1 describes overall requirements, J2931/4 is wired communications using PLC, J2931/5 is Telematics and J2931/6 is for Wireless Charging. J2931/7 includes the Security for each of these.

SAE J2953 Plug-In Electric Vehicle (PEV) Interoperability with Electric Vehicle Supply Equipment (EVSE). This is the series that include the requirements in J2953/1 and test procedures in SAE J2953/2, for all the previous documents, including SAE J1772's control pilot and proximity circuits and functions.

SAE J3072 Interconnection Requirements for Onboard, Utility-Interactive Inverter Systems. This document includes the requirements for onboard inverters to send/receive the grid signals for Vehicle to Grid (V2G) functions.

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

Purpose

The primary purpose of SAE J2847-2 is to provide the communication to achieve RESS charging control irrespective of RESS variations or energy storage technology.

SAE J2847-1 identifies the functional messaging for the PEV to connect to the utility or service provider and participate in available programs. This document, J2847-2, identifies the additional messages for DC energy transfer to the PEV.

The specification supports DC energy transfer via Forward Power Flow (FPF) from grid to vehicle, and DC Reverse Power Flow (RPF) from vehicle to grid is included in SAE J2847-3.1 DC Forward Power Flow is used to charge the vehicle's rechargeable energy storage system (RESS).
I'm interested primarily in what data the charger/utility can collect from the vehicle for privacy purposes, how the PLC communication can interface with other vehicle modules, and if/how persistent storage or flash or EEPROM modules can be accessed directly or over the PLC or a PLC->CAN bridge in the vehicle creating a malware injection point, particularly given that this is a full TCP/IP stack protocol. So far I have only found some basic summary information online.
 

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The relevant standards require payment, unfortunately. ISO 15118-2:2014 specifies the protocol messages between car and EVSE (and power infrastructure generally) and so sounds like the one you're most interested in.

I did find a paper from a smart power grid conference last week that goes into security implications of the SAE CCS charging standard:

A threat analysis of the vehicle-to-grid charging protocol ISO 15118
Bao, K., Valev, H., Wagner, M. et al. Comput Sci Res Dev (2017). "https://doi.org/10.1007/s00450-017-0342-y"
 

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Discussion Starter #5
Thanks to all for references (been out of pocket for over a week). I'll do some studying over the next few days.

My main interest is possible interfacing between (specifically) the Bolt and the multi-functional solar inverters such a Pika Energy (Islanding) and SolarEdge (StorEdge) that would essentially replace (or augment) the "backup" batteries (LG,Panasonic,Tesla Powerwall) with the Bolt's battery at the (380 VDC?) bus level. If such a "plug and play" interface could be offered, combined with electricity contracts available in my area (free nights), it would provide a strong incentive for solar installation on my roof.

Likely not much incentive for GM (nor my electrical provider to continue energy shifting incentives) to do so however.
 

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Discussion Starter #6
billatq;

Great information about CCS! Thanks so much.

The SLAC/OSI information (p 38-55) appear to be the keys to PLC communications along the hi-voltage DC bus - potentially even V2G protocols already defined? However, frankly, the protocols are so far above my head that envisioning the "hybrid" solar inverter manufacturers being able to interface for solar charging and V2H/V2G discharging - I have no idea about the possibilities! I just know that having such capabilities would sway me to go solar (within some cost reality).
 
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