Stand alone OBC/PDModule EV system Can 2015 - SOLVED

[Alibro]

You can't use three UNOs, since the timing will be off. Your #1 priority is to setup code that allows you to queue up messages correctly.

See this video for more info on CRC/MPRUN/CSUM
https://www.youtube.com/watch?v=oENNNfy5GSM

Thanks Dala, I guess that makes sense.
I'm working now so I'll take a look this evening.

[49thdiver]

I would suggest taking the GEN1 can messages from trusoln and use them to replace the equivalent can messages in my gen2 code. ie 1f2,11a,1d4.,etc. I know my code works and I also have confidence that trusoln messages are right from a gen1.
The best path forward would be to get a recording of gen1 car while charging and compare the messages and the sequence with what you have.
Dala is 100% right timing, crc and Prun is paramount. Also note the scheduling in my code works you just need to change the can messages. The 3 uno's will not help, one due is your best option. The code works on a gen2. It can not be that different, but I don't know not done it. If you know some one with a working gen1 get a recording. I have a friend who might let me splice into his wiring and grab a recording if you run out of options.

Myabe someone on this forum has a recording already ?

Do you have the interlocks bypassed, in the gen2 there is one in the battery pack and one in the inverter that are connected in the PDM.

It's time consuming, stay at it, working full time and having other commitments like you it took me two years to solve it. If you are under a time crunch you might find it easier to pickup a gen2 charger/pdm from an auto wrecker. Would be cheaper than an off the shelf charger.

[Alibro]

I would suggest taking the GEN1 can messages from trusoln and use them to replace the equivalent can messages in my gen2 code. ie 1f2,11a,1d4.,etc. I know my code works and I also have confidence that trusoln messages are right from a gen1.
The best path forward would be to get a recording of gen1 car while charging and compare the messages and the sequence with what you have.
Dala is 100% right timing, crc and Prun is paramount. Also note the scheduling in my code works you just need to change the can messages. The 3 uno's will not help, one due is your best option. The code works on a gen2. It can not be that different, but I don't know not done it. If you know some one with a working gen1 get a recording. I have a friend who might let me splice into his wiring and grab a recording if you run out of options.

Myabe someone on this forum has a recording already ?

Do you have the interlocks bypassed, in the gen2 there is one in the battery pack and one in the inverter that are connected in the PDM.

It's time consuming, stay at it, working full time and having other commitments like you it took me two years to solve it. If you are under a time crunch you might find it easier to pickup a gen2 charger/pdm from an auto wrecker. Would be cheaper than an off the shelf charger.

LOL, you must have read my mind Peter!
Earlier today I was looking at the codes and suddenly realised you have already done the heavy lifting.
The three CAN messages TrueSoln mentioned are already in your code so I've been REMing out all the bits he didn't mention and hope to try it again later.

[Alibro]

OK so I managed to turn off the CAN messages I didn't want from your code Peter (or at least the ones TrueSoln didn't mention) and connected the Due to the OBC but no joy. The three CAN messages are being sent as they are in your code and I still see a change to one of the CAN codes coming from the OBC when I plug in the granny cable but no charging and no sound of relays clicking. I will take another look at the low voltage connections for any mistakes and if anyone has any suggestions I'm happy to try them but starting to loose hope that I will get this working in the short term.

I have another crazy idea to use 21 x 19V 6A HP laptop mains adaptors connected in series to give 400V. It may sound daft but I happen to have the HP adaptors so will give it a try with 5. This will give me 5 x 19 = 96V which should be OK to charge 16 cells up to 4V each which should be good enough to confirm the concept. I accept this is probably not suitable as a permanent solution but might be good enough to buy me time to sort the charger I have or to replace it with one that has already been cracked like the Outlander PHEV charger.
It occurred that if one of the chargers failed for any reason it could have a very high voltage across it so I should probably put several fuses inbetween the chargers so hopefully that should help prevent disaster.
Any thoughts?

[49thdiver]

More later but to prevent a house fire you need to be very cautious. Conceptual it might work. The trouble with that scenario is the maximum voltage differential across all the adapters ie. 400 volts
Fuses wold be a minimum and of course each charger would have to spam X number of cells up to the 19 volts maximum. I have done this kind of thing with 12 volt chargers in older EV's up to 120VDC but not at the 400 volt level. Keep in mind cell balancing is often done at the battery pack level not in the charger. I think thi swould be less than optimal as balancing the pack may be a challenge with the nissan BMS competing with the laptop chargers and limited ability to manage the chargers.

Again a recycled GEN2 charger may be a good option for you.

[Alibro]

Yes it occurred to me that having potentially 400V across a single charger could be sub optimal.

Here is my thinking on using the laptop chargers.
Each charger is 19V therefore 21 x 19 = 399V

399V / 96 cells = 4.156V. This would be an acceptable voltage for these cells so ending the charging at a particular time would not be critical, so long as the chargers were not left connected for days.

The BMS can take care of individual cells to prevent them getting out of balance as it is already doing.

If I do this it will be purely as a temporary solution should I fail to get the Gen1 charger working.

[49thdiver]

Understood, and it may work. The issue I have identified is in the nature of switching power supplies which laptop chargers are. Its the maximum differential voltage across all the chargers that may cause cause the chargers to not work at all or blow in the worst case if one of the chargers fails which may cause an open circuit voltage swing over the rated DC outout voltage of the charger. I am not an engineer I discovered this in my research. It made sense at the time and I think I observed a situation where the chargers simply did not work. I was successful in using 12 volt wheel chair chargers and If I recall correctly was less successful using other chargers. Give it a try, just be safe as you have indicated you plan to be. I am just providing heads up.

[Alibro]

I've connected three together in the past and saw no issues when turning them off and on randomly however they were not under load, nor did they have batteries in parallel with them so this could still end up being a very bad idea.
I plan to do a test this evening with 5 chargers and 24 cells to see what happens.

[Alibro]

Unfortunately today has been a big fat fail.
I tried linking 5 PSU's in series as mentioned and could see 99V (as each were a little over 19V) however as soon as I connected them to the battery modules which were sitting around 92V the PSU's turned themselves off and refused to turn back on until I disconnected them from the battery pack.
As this was always a bit dodgy I'm not going to pursue it.
So then I had another look at the wiring and tried a few things to see if I could persuade the Gen1 OBC to work but still no joy.
I tried turning on the 12V to the OBC in different sequences as there are several 12V inputs which in the car come from different relays.
I tried your original code again Peter and my reduced version but nothing.

Here is a photo of the CAN with the reduced version.


I'm using a CANalyst-II here as I find CANHacker can be a bit flaky but the result unfortunately is the same.
So unless someone smarter than me can find a way to make the GEN 1 charger work I will have to either get a Gen 2 version or a charger from an Outlander PHEV. In the meantime I'm going to give up on this for now and concentrate on putting the batteries in the car.

Thanks to everyone who has tried to help me with this and if anyone has any more suggestions I will give them a try.

[Alibro]

Just in case anyone is following this and is interested in the multiple laptop PSU's idea I mentioned earlier, I got it working with 16 cells and 5 PSU's in series.
The pack was sitting at 92V and when powered on the laptop psu's were at 99V.
Connecting the psu's to the pack directly caused a surge last time which made them shut down.
So this time I connected a 12V, 60W halogen lamp in series with the psu's and turned them on before connecting to the batteries.
As soon as they were connected the light came on and the batteries started charging at 3A.
For various reasons this is very dodgy and could go badly wrong so if I end up doing it for the EV pack at 400V it will be very much a one off emergency thing but I thought it worth mentioning.