Tesla Model 3 Rear Drive Unit Hacking

[Jack Bauer]

That's why we have the modboard:)

[Jack Bauer]

Just arrived:)

[MX5EV]

I purchased this Launchpad I'd definitely be willing to help as well. Though I don't have a ton of experience programming TI parts. I'm going to try and figure out how to blinking the LEDs mentioned.

Hopefully, once we end up with these motors overflowing at junkyards the price will come down.

[station240]

One downside of that TI Launchpad board is not all the signals are available.
There is a very tiny connector on the underside with some extra signals, it's cell phone connector small, and TI never did release that addon board to break it out.

Oh and only CANB is connected to a transceiver, CANA needs an extra transceiver chip added (think I'd had bad luck getting that to work)
To be honest we probably need a custom made TMS320F28379D board, for development as Drive Unit PCBs are kinda expensive and come with a heavy lump attached.

I have my own custom TI board for a different processor, however it's just a block of blank PCBs and components till I get everything I need to assemble one. It does have Isolated CAN and JTAG over USB, which I could re-use.

[JaniK]

Have you found anything in the resolver signaling "sawtooth" or other parts in inverter that would prevent running the M3RDU in reverse?

[Jack Bauer]

Nope. And with the electric oil pump it can go full bore in reverse without and mechanical mods. Now I just need to make some time to fit and test the new modboard....

[JaniK]

Cool. Thanks for fast answer.

[Jack Bauer]

Finally back at the M3 rear du. Time to swap out the old V1 modboard for the V2 and see if we can run closed loop with the inverter back on the drive unit:)

[Jack Bauer]

Also since I've been away seems this guy has had some major success

[Jack Bauer]

Good news is the V2 modboard resolver circuit is working perfectly. We are now driving the original Tesla amp and reading back via their filter. BAd news is it seems my current sensor signs are flipped so no foc tuning today.

[Jack Bauer]

Ok I'm an idiot. Just had to set il gains and ocur lim to negative and we have full closed loop control:)

Muhahahah.....hahah......waahhhhahahahahah

[JaniK]

Good work and great news!

What happened with the oil choice?
Is there a good choice or just random choice?

[Jack Bauer]

I have a gallon of Dexron 6 waiting.

[Jack Bauer]

At this time I have decided to do a full opensource release of all design sources:)
More updates and video to following including testing in a M3 front DU.
https://github.com/damienmaguire/Tesla- ... Drive-Unit

Rear drive unit now responding to throttle commands in both directions with regen.
To Do :
Secure mod wires.
Button up the inverter
360v full test.
Make install video showing every step (super boring) in a front DU
Run front DU
Retire to Lanzarote on the profits.

[Isaac96]

Great!
Front DU is induction IIRC, does that make for easier tuning and probably easier integration into vehicles?

[Jack Bauer]

[JaniK]

Does it matter what type of wiring to use between modboard and M3 inverter PCB ?

Min/max. gauge? Insulation thickness?

Or do we just us some leftovers from a computer power supply etc.

[Jack Bauer]

I'm using kynar wire most commonly used for wire wrap boards. E.g. :
https://www.digikey.com/catalog/en/part ... eries/1966

I'll go through all this in the forthcoming installation video.

[mdrobnak]

The motorsports industry generally uses wire with ETFE (Teflon) / Tefzel wiring. It allows the jacket to be thinner, saving weight. Also highly resistant to things like fuel, etc. Apparently also used in spacecraft - https://en.wikipedia.org/wiki/ETFE

-Matt

[JaniK]

Thank you both for replies

I found full rolls of kynar wire and thats a bit much.
Maybe I didn't look too hard.

For ETFE I found this item that ships per foot...:
https://www.mouser.fi/ProductDetail/TE- ... YKmg%3D%3D

+200°C max temp and 600V rating, seems ok to me?

Unless a Damien board ships with a string of wire..

Thoughts?

[Jack Bauer]

I may decide to offer a kit with wire. Will see what happens once sales start.
Finding the last few signals today before hv testing.

[EV_Builder]

Damien wouldn't it be nicer to un-solder the IC and solder a board with connector to the board?
Or maybe just a legged board with connector? long enough that you can solder the pin to the old IC pad?

Did you consider this? or do we need every other pin pulled-up anyway?

[Jack Bauer]

Yes I did indeed think of that at the outset. There were problems with that approach however. That said I am working on a neater solution:)

[Jack Bauer]

Oil pump controller used in both front and rear drive units is an Onsemi LV8907.
https://www.onsemi.com/products/power-m ... Session=-1

[Jack Bauer]

Scratched an itch and tried Jtaging the Musk brain. Imagine my surprise when it didn't work. Oh well, better give up and go home ....
Attached pinout (as best as I could make anyway) of the 10 pin Jtag port.