The Society of Automotive Engineers' Hybrid J1772 Task Force met on June 22nd to review progress on electric and plug-in hybrid charging and electric vehicle supply equipment (EVSE).
Attendees included at least reps from the SAE, TEPCO, Tesla, BMW, LS Cable, Plug Smart, CCI, GM, Ford, Chrysler, and the Electric Power Research Institute (EPRI).
An important point: The J1772 Surface Vehicle Recommended Practice includes alternating current (AC) Level 1 (L1) and 2 (L2) provisions, as well as direct current (DC) Level 3 (L3) charging. The task force has completed the L1 and L2 recommended practice and connectors and equipment are on the streets.
The focus now includes fast-tracking the L3 portion of the specification. The L3 implementation being defined by the J1772 Task Force is not the CHAdeMO/TEPCO L3 connection currently used in Japan and with which the Leaf is fitted.
- The J1772 recommended practice includes a provision for locking the connector into the vehicle during charging. This is to deter charge cable theft and also parking lot cable hijacking. The decision to implement a locking provision is up to the auto manufacturer. [At least one manufacturer rep was happy to learn about the existence of the provision...]
- By the 27th of July, the EPRI should have the J1772 EVSE test documents finalized. [The test procedures have procedures for testing both EVSE with continuous current adjustment capability, as well as EVSE devices that have 'discrete' charge levels and/or settings.]
- The timeline for the 'L3 add-on' has slipped at least a few months. The target to finish the DC portion of the J1772 standard is December 2010. The task force team is very aware that vehicles will be 'on the streets' in the US in December...
[note: Considering that vehicles will be shipping with CHAdeMO connectors around the time the DC portion of J1772 is being ratified, and considering the momentum behind the Japanese L3 standard, it appears that J1772 L3 is not going to be a factor in the first generation EVs. Will this create a VHS/Beta decision for the industry later?]
- One critical part of L3 charging is communication between the car and battery charger. A number of methods are being evaluated, including signaling over the DC power lines to the car, and signaling 'on top of' the L1/L2 pilot signal. Nissan is working on the required L3 communications messages.
- The DC L3 standard is defining the duty cycle for the connector as 20 minutes 'on' and 10 minutes off. [note: It wasn't clear if this was the duty cycle repeated for a single vehicle, or if it was based on a 20 minute charge for a single vehicle followed by 10 minutes to disconnect, move, and connect the next vehicle to the charger.]
The next meeting was originally scheduled for July 27th, but will be rescheduled as many of the Task Force members will be attending the Plug-In 2010 conference
. <- link...
This document from Feb '10 gives an overview of L1 and L2, as well as a comparison of the J1772 DC plan and the JARI/TEPCO/CHAdeMO L3 interface. http://grouper.ieee.org/groups/earthobs ... Kissel.pdf
Here's a link to the SAE works in progress page for plug-in vehicle standards: http://www.sae.org/servlets/works/docum ... tPage=wIpS