Mini-QC Rapid-Charger (RC) Project for LEAF QC Port

[OakLeaf]

Congratulations on all the great work done on this project so far!

A few days ago, while doing some research on what might be involved with building a high power AC / DC converter I came across the following web site:


http://www.smps.us/


It has a lot of good general info, as well as many links to other detailed reference design material.


Some sections that looked especially interesting:


http://www.smps.us/topologies.html

http://www.smps.us/smpsdesign.html

http://www.smps.us/Unitrode2.html

http://www.smps.us/Unitrode.html

http://www.smps.us/magnetics.html



You may have some other design direction in mind, but hopefully, this is close to what you are looking for.

 

[garygid]

Good educational info, thanks for the links.
Still hoping to find an expert to help out.

 

[OakLeaf]

Unfortunately, my experience is all low-power (under 60W) DC/DC converters and generally making things operate on as few electrons as possible.

Aside from using a battery charger such as you're using now, is there any possibility of adapting some other "off-the-shelf" AC/DC module (such as a motor controller) that would be suitable for the task, or is it the case where you're trying to reach a specific component cost?

 

[garygid]

So far, I have not found an isolated 12 kW (240v, 50A) power supply,
or something similar. That doesn't mean they are not made, but
just that it is not obvious (to me) where to find them.

Sure, any help finding them would put us substantially ahead,
and probably allow others to obtain experimental mini-QC systems.
That would be a huge step forward.

We have struggled with getting this "experimental" power supply
under sufficient control to reliably mini-QC two different LEAFs.
We need to test other LEAFs, different years, and with different
firmware updates.

This has enabled us to better explore the QC protocol and
endeavor to understand it well enough to do reasonably
safe and dependable charging.

True, there are some bits that we have never seen change value,
mostly all zeros, but we think that our logging is working well,
and that we have a first-order understanding of most of the data.

However there is some that is still elusive in meaning or function.
These values might be meant for optional functions, and our
tests have been with what appears to be version 0.9 QC sofftware,
but the 2013 model might have the 1.0 version.

It appears that the LEAF has 4 main criteria for terminating a QC
session from its side:
1. The Battery Pack is full (enough) - expected
2. When charging from "under 50%", it stops somewhere before full,
usually less than the "80% level". - an advertised feature of the LEAF
3. When exceptional conditions occur, faults and errors in process.
This might include Battery Pack temperatures too high. - expexted
4. When 60 minutes has passed. - a previously unknown feature?

More Later, Gary

 

[TickTock]

You can always put in an isolation transformer on the feed - just need more floorspace since a 12kW unit will be big and heavy. Occasionally you see used ones show up on eBay for <$500. Many can be reconfigured to support 480,240,207, etc (make sure you check the power rating for the desired voltage - assuming to be 240 in your case) and you can actually use a 3-phase transformer for split or single phase - just need to derate the power rating (need to get an 18kW 3ph to use as 12kW split phase). Main downside is the 3ph are bigger and generally a lot more expensive but you can find a good deal on eBay time to time.

 

[garygid]

I got this question:

Can you provide a spec you are looking for?
Input is as stated 240v , 50A, what do you need
on output and what control interface do you require?

Input nominal 240v, and near 50 amp.
Power Factor correction, and isolation.
HV+ and HV- and one or two controls exposed,
Max Voltage and Max Current limited, with voltage
control at no load, and current control otherwise.

The input fused, perhaps with resetable thermal fuses
or breakers. Start and Stop buttons, and perhaps an Output
diode to protect against back-current, and fuse or breaker
short-circuit protected as well.

Output voltage a few volts, near 0, to around 450v unloaded,
preferably nearer 500. Ramp up, with no load, and ramp down,
perhaps 1 or 2 seconds each way, under control from a uProc,
peraps a command argument*2 = 510v max (2v resolution).

Current control from 0 to about 30 amps at near 280v up to about 400 volts,
with about a half-second (or tenth-second?) max delay in following a 2-amp
per 0.1 second ramp up, and a quicker shutdown. We are gradually discovering
what the car's limitations are, by occasionally bumping against them.

Measure temperature, v-in and out, and current in and out,
power factor, some internals, etc.

The controller might be an AVR-CAN board/chip with an isolated power
supply so that it can be Grounded to the car's signal ground.
Thus, optical isolation fro the Power Supply controls and measurements.

About a cubic foot (plus the I/O cables) or less, with fairly quiet air cooling,
High enough efficiency so that simple air-cooling is sufficient.
Work at ambient -20 F up to at least 120F (some wide Automotive range),
and with a wide range of humidity.

Not "too" heavy for most to lift, and put into, and remove from, the trunk.

At least that is more or less off the top of my "thinker-organ".
Hopefully, it helped a little.

Perhaps somebody else can put the specs into words better?

Edited for better spelling, meaning, and a significant typo of 2v to 2-amps.

 

[garygid]

Well, we have verified that one can QC, apparently successfully, but
also generate a Warning code that can be cleared simply by turning
the LEAF On and Off (perhaps a couple of times).

Another code can be cleared with a re-boot of the car, but a third
code DISABLES charging until the code is reset ("by the dealer").

So, BEWARE, and please attempt any experiments wisely.

 

[GregH]

Well, we have verified that one can QC, apparently successfully, but
also generate a Warning code that can be cleared simply by turning
the LEAF On and Off (perhaps a couple of times).

Another code can be cleared with a re-boot of the car, but a third
code DISABLES charging until the code is reset ("by the dealer").

So, BEWARE, and please at tempt to experiment wisely.

Have you determined which actions (or inactions) caused the various faults?

 

[garygid]

Well, we have verified that one can QC, apparently successfully, but
also generate a Warning code that can be cleared simply by turning
the LEAF On and Off (perhaps a couple of times).

Another code can be cleared with a re-boot of the car, but a third
code DISABLES charging until the code is reset ("by the dealer").

So, BEWARE, and please at tempt to experiment wisely.

Have you determined which actions (or inactions) caused the various faults?

Nope, nothing obvious yet.
We hope to find out the actual "code" later today.

Might be the charging current fluctuating too much at low charge rates, or...??
We still need to examine the Log closer, for more detail.

 

[jclemens]

I have updated my thingiverse page to include a disclaimer. I hope it is not too colorful for some folks.
I have also added some details about the signal pins, of which can be summed up in this photo.

thingiverse link
http://www.thingiverse.com/thing:121581

 

[garygid]

Are any of the LEAF's Fault / Error / Warning Codes
listed in the Service Manual?

Does anybody recognize the P31AC code?
Edit: Apparently P31CA, not AC.

Some "mild" (warning?) codes can be reset by just
turning the car Off and On (perhaps a few times).

Does anybody know how to cause one of these
"faults" reliably, for testing of reading the LEAF's
Error Codes? Thanks.

 

[jclemens]

Are any of the LEAF's Fault / Error / Warning Codes
listed in the Service Manual?

Does anybody recognize the P31AC code?

Some "mild" (warning?) codes can be reset by just
turning the car Off and On (perhaps a few times).

Does anybody know how to cause one of these
"faults" reliably, for testing of reading the LEAF's
Error Codes? Thanks.

There are many many DTC codes in the service manual, however, I cannot find that particular one. It is funny the EV control system (EVC) has similar ones listed, actually it goes from P31A9 to P31AF and skips P31AC.
but that entire range refers to communication errors.
Various DTCs have various fail safe patterns.

FAIL-SAFE PATTERN
• Pattern A: Quick charge prohibited
• Pattern B: Normal charge prohibited
• Pattern C: READY OFF
• Pattern D: High-voltage power supply stop

I believe pattern D would be what we call "bricked"

How were you able to read the DTC? are you sure it is correct?

 

[Ingineer]

Does anybody recognize the P31AC code?

There is no P31AC that I've found regardless of year. There is everything around there, (P31AB and P31AD) and almost everything in that area (P318D-P31B9) is related to CAN faults.

-Phil

 

[garygid]

Perhaps this will be better or more nearly correct info:
Apparently, Code P315C (perhaps indicates the device or area
with the problem?) led to (detail code?) P31CA (not AC).

 

[jclemens]

DTC: P315C (can have any/all fail safe modes enabled depending on type of fault)
Trouble diagnosis name: CHARGE RELAY
DTC detecting condition: VCM detected P31C8, P31C9, P31CA or P31CB.
Possible cause:
• Harness or connectors
• Normal charge relay
• Quick charge relay
• On-board charger

DTC P31CA - has fail safe pattern B (will not charge)
Trouble diagnosis name: ON BOARD CHARGER
SYSTEM
DTC detecting condition: VCM received quick charge relay (-) stuck signal from on board charger. [DTC P31CB is (+)]
Possible cause:
• Harness or connectors
• Quick charge relay
• On-board charger
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
• Turn power switch OFF and wait at least 20 seconds.
• Make sure that 12V battery voltage is 11 V or more.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
With CONSULT
1. Start quick charging and wait at least 30 seconds.
2. Stop quick charging and wait at least 30 seconds.
3. Turn power switch ON.
4. Check DTC.

It seems consult III is required to erase this DTC

 

[Ingineer]

Perhaps this will be better or more nearly correct info:
Apparently, Code P315C (perhaps indicates the device or area
with the problem?) led to (detail code?) P31CA (not AC).

Ahh, that explains it!

P315C is labelled "CHARGE RELAY" the description is "VCM detected P31C8, P31C9, P31CA or P31CB".

The possible causes are listed as:
• Harness or connector
• Normal charge relay
• Quick charge relay
• On-board charger

P31CA & P31CB are listed as "QUICK CHARGE RELAY" with a description of "VCM received quick charge relay (-) stuck signal from on board charger".

There is a Note:
If DTC P31CA or P31CB is displayed with DTC P3101, first perform diagnosis for DTC P3101.

Possible Causes are:
• Harness or connectors
• Quick charge relay
• On-board charger P31CB VCM received quick charge relay (+) stuck signal
from on board charger.

I would gather this means voltage was detected on the CHAdeMO side of the relay after it had already released it. This means your power supply was still pumping after the supposed controlled shutdown.

-Phil

 

[garygid]

Thanks, Phil.
Your insight is greatly helpful.
Cheers, Gary

 

[garygid]

It has come to my attention that most, at least newer, cell phone
towers have high voltage battery backup, typically around 600v.

So, there might be some associated technology for our power
supply design efforts. If anybody finds useful information,
please let us know.

Cherrs, Gary

 

[Ingineer]

It has come to my attention that most, at least newer, cell phone
towers have high voltage battery backup, typically around 600v.

I have a good bit of experience with these power systems, and there are almost always only 2 voltages used: 24V and 48V. (For pure cellular it's usually 24V) They are also almost always lead-acid.

Since most of the sites now are "single cabinet", there simply isn't space for a huge number of cells in those voltage ranges, so I'm not sure where you heard that.

Even large telecom central offices are all 48V with huge battery farms that can sometimes occupy several floors.

-Phil

 

[GlennD]

In our Signal Hill radio site we have a large 48V battery bank for the microwave and a 500V battery bank for the full time UPS.

There is no way to access anything other than 48V or 120VAC. The high voltage battery is solely for the UPS.