Basic Tesla charger question: Does the Tesla DC fast charge(and possibly other DC fast charge protocols) go through the charger? If so, can it be enabled as well as the AC charging functions?

 

Basic Tesla charger question: Does the Tesla DC fast charge(and possible other DC fast charge protocols) go through the charger? If so, can it be enabled as well as the AC charging functions?

In general, no. I don't have in-depth knowledge of the Tesla super charger but how fast charging tends to work is that the car has contactors that connect the car's battery straight to the DC fast charger itself. The fast charger then has all the charger goodies in it and handles the current and voltage limiting outside the car. The car reads voltage and current itself and sends commands to the external charger about what it would like to do. In an emergency the car always has the option to open its contactors. So, the on-board charger really isn't involved in all this but the battery management system most certainly is. Now, that all holds for CHAdeMO which I do know about. But, I can't imagine the super charger is any different.

 

I suspect from the wiring diagrams and the complexity of the charger logic board that the charger handles the Supercharging control. One question for Colin : now can I tell the frequency of a message in Savvycan? going to attempt to write a simple program to get the charger to ramp up to 2A and stay there.

 

I suspected it was the HVJB that engaged or not the charger, and thus handled DC supercharging.

Jeff

Sent from my Nexus 7 using Tapatalk

 

Time stamps.

looks like the contol messages 0x368, 0x42C and 0x45C are not as fixed as the response. varying from I believe 100ms to 200ms. or 5-10 messages/second

 

Never knew that was there! Thanks Colin Looks like all 3 messages are on 100ms time interval.

Gotta get me a 72A charger

 

I bett the charger will work with almost the same setup.

As why change something if it aint broke. And again three modules making up one unit.

 

We have arduino control of the charger

 

Yessss

So you can make any voltage or current you want?

Now it would be fun to test it in a three phase setup, if you have a three phase socket to test from.

 

Won't need three phase. Just 45Amps at 230v single phase for a full power run. Video on the way

 

Shall I change your hard coded messages into something more useable?

Like setting output voltage and current plus ramp up time?

 

Here is the video :
https://youtu.be/7GwXQtd7RPY

Yes please Tom. I need to spend some of that Patreon money on a programming book

 

Uploaded 3phase_command_msgs_22kw.csv the github. We did a capture in my friends car today running from a 22kw 3 phase public evse. Car has dual chargers. Interesting thing is the command messages are identical for each power module. Should be very easy to run at full power.

Another finding today is the charger will work down to less than 150v and current increases with decreasing voltage for the same setpoint.

 

Damien, did you command 150V?

Otherwise the charger is just hitting the constant current as defined in the control message.

how ever one of the parameters that get sent to the charger will contain the AC current limit.

Can you ask your friend if you can monitor the charger when you plug in the wall adapter charger, should be limited to 13Amp ac.

 

No I didnt change anything just the pack voltage by moving a tap around the pack. With the same settings it charged 1.9A at 365v and 4A at 155V and 3A at 225v.

 

Is there any pin on the DUE that would be best to use for reading the evse pilot signal? Or can it use any digital pin?

 

Well, it'd probably be most efficient to use one of the timer/counter pins (TIOA or TIOB pins). They can count pules and such for you which makes it a lot easier - just let the hardware figure out the pilot duty cycle for you.

Otherwise any digital pin could work but you'd have to very quickly check the state of the pin several times per second. Or, integrate it into an analog signal and then read that signal with one of the analog pins.

So, I guess that's three options. Doing TC mode with a TIOA/B pin is a bit more complicated in software but not so bad. Probably the easiest in software option is to turn the PWM pilot signal into an analog signal but that's more hardware for you to put on the board.

Oh, and congrats on getting it to work! Before you know it you'll have the whole car running on custom logic boards. Autopilot next, right!?

 

Did a little more work on the charger logic board.
https://github.com/damienmaguire/Tesla-Charger/blob/master/Charger_Gen2_V1 - Schematic.pdf

Keeping it simple for now. Might add RS232 for people not wanting to use CAN.

 

Thanks to Tom's software and a few tweaks we can now turn the charger on and off , set a setpoint voltage and current. When the battery hits the voltage setpoint the charger ramps the current down to maintain the voltage. I suspect there is lots more functionality in here but basically : we got this thing

 

we got this thing

Congratulations to everyone who contributed... wonderful milestone

 

Not had a chance as yet to determine the minimum voltage point. Didn't receive any messages back from the charger and didn't have a chance to investigate. Colin, I made a few mods to your charger dbc file and had it working very well with voltages and current and then of course forgot to save it! Will re do it asap. The autopilot logic board is a few weeks away

I might do a live stream in the shed with the charger so people can make requests.

 

Quick video from yesterday : https://www.youtube.com/watch?v=BG4kYsoHe54

 

Somebody get this man a Gen 3 charger, to also work on!

 

Now for the fun part. Let's replace that paranoid Tesla logic board with a nice open source, chilled out version

 

Components placed on the new charger logic board. I seem to be making a habit of replacing high component count Tesla boards with low component count versions

 

Released the design files for V1 charger logic board.
https://github.com/damienmaguire/Tesla-Charger

Going to do my usual procedure of waiting a week before ordering boards to let my subconscious find all the screwups.

 

you go ,how do you get so much done

 

PCBs ordered for the V1 charger logic board. Also updated the design files over on Github with a few tweaks. Nothing major just tightening up the mounting hole positions and putting in a few headers for critical signals : https://github.com/damienmaguire/Tesla-Charger

 

Interesting. I have 4 chargers sitting here on hand and may order a board to help with testing. I'm happy to tear 1 or 2 of them apart.