Tesla Model 3 Rear Drive Unit Hacking

[uhi22]

Sorry I'm late with the review of the schematics.
Regarding the throttle inputs: I'd propose to re-arrange TVS and the serial resistor, to make these inputs 12V tolerant. It is a good rule, to avoid circuits which are killed by just putting 12V on them. In best case, even +12V and -12V should not lead to smoke. So I propose to put the TVS behind the serial resistor, and not directly to the pin.

[Jack Bauer]

This is how it's supposed to work

https://openinverter.org/wiki/Parameters

Yes but the front M3 drive unit is an induction motor not PM so am trying to run with sine firmware not FOC. Sine needs to know only rotor direction and rpm. In both screenshots above , the rotor is stationary. Sorry if am missing something obvious.

[Jack Bauer]

So ran some more tests. Set fslipmin to 2Hz. In manual mode I can set a freq and ampnom and the rotor will turn as expected. In this case angle behaves as expected but speed(rpm) is always 0. In run mode upon starting the inverter injects current and 2Hz into the motor. Pressing the throttle increases current as expected but as the sw does not see motor rpm it just sits at 2Hz and keeps increasing current.

Edit : in fact rotordir remains at neutral so the control loop is not seeing direction or rpm.

[Jack Bauer]

Annnnnd.....forget all that its working perfectly

[r1ckyb0nd]

With the new board does this make the 990 have the same output potential as 980 models?

[davefiddes]

Annnnnd.....forget all that its working perfectly

Good! I was at a loss to know what the problem could be.

With the new board does this make the 990 have the same output potential as 980 models?

Unfortunately not. The 980 has 4 pairs of mosfets per phase but the 990 has only 3 pairs. As with other OpenInverter boards you'll have free reign to configure the inverter to do what ever it can do with what it has got.

[Jack Bauer]

[Jack Bauer]

V THREEEE is ordered! Mars or bust.

[Jack Bauer]

In production

[johu]

Off-topic posts moved here: viewtopic.php?t=6707

[davefiddes]

I've been making steady progress on the firmware side of things. Nothing particularly glamorous. There have been problems with the reliability of configuration via CANopen SDO which are now fixed. I've also added support for fetching error logs from the inverter which works with the most recent OpenInverter CAN Tool release. A volunteer to add support to the esp32-web-interface would be nice...

I have made a bunch of changes to make sure that the firmware for this project is obviously distinct from johu's stm32-sine releases. Firmware builds (and releases in the fullness of time) are automatically tagged from the status of the git repo. This makes things more traceable to the project:

Code: Select all

$ oic read version
version             : M3_DU_v5.39_test-2-ga39941c-dirty-sine

The version string always starts with "M3_DU" followed by the core version number. It'll start at 5.39 and follow normal semantic versioning going forward. The "test-2-ga39941c" part indicates that the version is two commits after the "M3_DU_v5.39_test" tag and has a short-hash of "a39941c" which you can look up in git if desired. The "dirty" suffix is added to indicate this build came from a git repo with uncommitted changes (bad Dave). Finally the "sine" suffix indicates this unit is running "SINE" firmware rather than "FOC". Changes to the git repo force a parameter database checksum change so that OpenInverter CAN Tool and esp32-web-interface will report the correct version string.

Official releases will be much shorter e.g. "M3_DU_v5.39.0-foc".

I've updated the README and made the "M3_DU" the primary branch on my project repo: https://github.com/davefiddes/stm32-sine

[Jack Bauer]

Thanks Dave. Thats amazing work. With a bit of luck will have boards next week.

[Jack Bauer]

Just to keep folks informed , Irish customs have seized the V3 boards for an "inspection". AFTER making me pay the import fees of course. If this follows previous precedent I'll have to prove I'm the importer , prove payment etc etc. Its a bit like the movies where the cop doing the ransom drop is ran around all the phone boxes in the city...Could be a few days or a few weeks

[johu]

Which carrier did you choose? Found UPS to be the least troublesome in that regard. But that is Germany after all...

[Jack Bauer]

Yep. UPS. Previous experiences had been with DHL. Quickest customs turn around ever.

[Jack Bauer]

Looks good. A request please. IF you are not posting about this project or another open source option then please start a new thread.

[Bigpie]

Post moved.

[Jack Bauer]

[Jack Bauer]

[Jack Bauer]

Getting boards ready for beta testers.

[Jack Bauer]

Well, here it is folks. The beta release : https://www.evbmw.com/index.php/evbmw-w ... -3-du-beta

Now five of you unlucky persons can own a piece of history and fund my early retirement to Lanzarote......uhhh...cough...I mean fund further development and opensource releases. Video will be up soon showing the fitting procedure etc. Do note this is a beta board, not a finished product and DO NOT buy this if you do not understand the risks and are willing to provide feedback and work through problems here on the forum.

[Jack Bauer]

Working on the installation video.

[davefiddes]

To support the M3_DU Beta PCB I've made a first release of the firmware which can be found here: https://github.com/davefiddes/stm32-sin ... DU_v5.39.0

This is the code that Damien has been testing with so basically this is what everyone should be using as well.

[Jack Bauer]

Thanks Dave. Could you add a line to turn off pin PE12 at startup? This will disable the big active discharge resistor bank in the middle of the board. Gets a bit toasty at 400v

[davefiddes]

Now you tell me.