Tesla Large Drive Unit Support Thread

[Jack Bauer]

UPDATE : Sales of built and tested Tesla boards are suspended as of 15/04/20. All orders placed will be fulfilled. I am doing this in order to concentrate on new developments (model 3 etc) and focus on Toyota/Lexus in order to enable lower cost conversions. The opportunity is now there for someone to fill this gap. I would hope that if someone does step up it is done so in a way that respects the opensource philosophy and the work put in by Johannes and myself.

Wiki: https://openinverter.org/wiki/Tesla_Mod ... %22LDU%22)


johu: I'm closing this support thread as it has become too long to be useful. Please describe new issues in a new thread with a descriptive title (I NEED HELP is not descriptive!). Do not put unrelated issues into existing threads that describe a different topic.

Setting up a support thread for the open source large drive unit control board.
Built and Tested boards available from the webshop :
http://www.evbmw.com/index.php/evbmw-we ... ted-boards
Bare PCBs for those who wish to build their own :
http://www.evbmw.com/index.php/evbmw-we ... are-boards
Github resources :
https://github.com/damienmaguire/Tesla-Drive-Unit
Wiring diagrams :
https://github.com/damienmaguire/Tesla- ... g_Diagrams
Firmware releases :
https://github.com/jsphuebner/stm32-sine/releases
When updating firmware always use the stm32-sine.bin NOT stm32-foc.bin.

PLEASE READ THE THREAD OR USE THE SEARCH FUNCTION BEFORE POSTING A QUESTION. YOU WILL PROBABLY GET AN ANSWER MUCH FASTER THAT WAY

Wiring diagrams attached to this post.

Video showing inverter powerstage teardown :


IGBT Used in the inverter :
https://www.infineon.com/dgdl/Infineon- ... 2890113e25

https://www.mouser.ie/ProductDetail/Inf ... PIhAA3M%3D

Here is a video detailing exactly how support works for Tesla and other logic boards from the evbmw webshop. I would encourage anyone considering a purchase to please view this video and ensure you are comfortable and familiar with the support structure around these products.


Update : 21/01/20 : V4b design files now released. Both fully built and partial built boards available from the EVBMW webshop : https://www.evbmw.com/index.php/evbmw-webshop
Don't want to buy from me and support ongoing development? That's ok as this release also includes the BOM, CPL and Gerber files needed to build your own at JLCPCB : https://jlcpcb.com

[Jack Bauer]

Here is a video of my BMW E31 running on the dyno with a Tesla large drive unit and open source logic board.

[Jack Bauer]

The number one most common question I get asked is why is the motor only turning slowly when I press the throttle.

The symptom of the motor turning slowly is almost certainly caused by a missing or inverted encoder signal. The encoder output consists of two channels : A and B. The signal from these is used by the microcontroller to determine the speed and direction of rotation of the motor. If for example the A and B signals are swapped then the inverter will be trying to drive the motor in one direction and the encoder signal will tell it the motor is running backwards hence this behaviour. If either or both signals are missing then the microcontroller has no speed or direction information and the same symptoms result.

[x.l.r.8]

I have a relatively simple question regarding inputs to the LDU 23 way connector. I have 3 momentary buttons selecting N - R- D like the roadster, I'm using a UNO with a relay shield to control the inputs. R and D will obviously trigger pins 8 and 7 respectively. In N I wish to inhibit any input from the accelerator, the power to either drive pins will be dropped from the UNO but as a redundancy I was hoping I could direct the feed from the 3rd relay to say pin 14 (brake pressure switch), would that inhibit the throttle from working?
PS its probably a simple program for any of the usual members here but if you require a switch pack using momentary buttons to select drive my first attempt at writing a program since my BBC B computer was actually a success

[tom91]

The brake input, creates a negative throttle so regen command. I would strongly suggest otherwise as this can cause unexpected behaviour.

Please look at making sure you get the watchdog running in your UNO, as this application will not want any of those nasty arduino lock up issues.
https://folk.uio.no/jeanra/Microelectro ... chdog.html

Why do you not simply cut the 5V feed to your pedal with a relay?

[x.l.r.8]

If I use the watchdog it will simply reset the board, that would also lose drive and on a road car I see some validity but on a race car not sure its going to make a lot of difference. That and the fact I skipped over the blinking of LED's so I really am not at a stage to follow the program right now, and I learn slowly at my own pace, I'm only trying this as I don't want to use diodes and latching relays which was the first build I did, I thought I'd teach this old dog a trick.

I could certainly use the output on the N to drop the throttle power if I use the relay in NC configuration, I had not thought of that.

[Jack Bauer]

So in "N" or neutral, the throttle is ignored. If you were to remove it's 5v supply it might cause it to go out of range and trigger an error in the inverter.

[Jack Bauer]

Another one for the FAQ list regards the encoder on the large drive unit. Unlike the small drive units the encoder must be wired externally from it's 4 pin connector to the 23 pin main input connector via a screened cable. If you are unlucky and don't have the Tesla harness then stranded CAT5e or CAT6 network cable is a good substitute. I have attached some pictures from the Tesla wiring diagrams detailing pin connection from the 4 pin encoder connector (located on the end of the motor housing) to the 23 pin ampseal connector.

Here we have the pinout of the 23 way ampseal connector :
https://github.com/damienmaguire/Tesla- ... NEW_V2.pdf

Pin 1 of the Encoder connector to Pin 17 of the 23way ampseal main connector
Pin 2 of the Encoder connector to Pin 16 of the 23way ampseal main connector
Pin 3 of the Encoder connector to Pin 10 of the 23way ampseal main connector
Pin 4 of the Encoder connector to Pin 9 of the 23way ampseal main connector

The screen on the cable should be connected to pin 18 on the 23 way ampseal connector. It is not connected at the encoder plug.

The Encoder plug is very hard to find. ZeroEV have them for sale on their webshop :
https://zero-ev.co.uk/product/tesla-lar ... model-s-x/

[tom91]

Adding onto the encoder cable, if you ever have issues getting a stable spinning motor, Always plot your rpm/Fstat as if that is really jumpy it means the encoder signal is dirty.

Shielded cable is a must, without it the encoder pulses are not clean enough.

[Permag]

Encoder wiring. I think it is important to let everyone know that when installing the 2013 p85D LDU in the porsche, that the encA and B signals had to be inverted (I swapped the pins at the motor connector) before this it would only turn very slowly when set to single encoder mode. Damien and I have discussed this and it seems there may be minor schematic differences between years.

[jon volk]

I too had to swap signal wires at the encoder. I strongly suggest powering up at low voltage and verify smooth running. My symptom was a slow jogging. I swapped the middle two wires and immediately had smooth running. It does seem that there were some variations through the years. Perhaps its just a Connecticut thing

[Jack Bauer]

Another FAQ : All fully built boards purchased from the EVBMW webshop are programmed and ready for testing and use. There is no need for initial programming. Firmware updates may be accomplished over the web interface and may be downloaded here :
https://github.com/jsphuebner/stm32-sine/releases

[Jack Bauer]

Another FAQ : The web interface.
Once 12v power is applied to the board or drive unit the wifi interface becomes available. Simply connect with any wifi enabled device (laptop,phone,tablet etc) to the wifi access point called inverter. The passphrase is inverter123. Once connected point any web browser to 192.168.4.1 to bring up the interface. Note some devices may complain about not being connected to the internet but just ignore.

[Jack Bauer]

Another FAQ : Low voltage testing.
It is recommended to perform initial tests at a low DC bus voltage in order to confirm correct operation of the drive unit and logic board. The voltage should be between around 40 and 100v dc. Some parameters need to be set to enable operation at these voltages.
UDCSW set to 0.
UDCMIN set to 0.
You will need to perform a manual precharge or set UDCSW to about 10v less than your test voltage and use drive unit contactor control.
Don't forget to reset these parameters to their original values when finished testing.

[Jack Bauer]

FAQ : Precharge system.
The precharge system behaves as follows :

Upon application of 12v power, energise precharge contactor.

If after 5 seconds the measured voltage at the drive unit (UDC) does not exceed the UDCSW parameter we shutoff the precharge contactor as it is assumed the precharge has failed in some way.

If during those 5 seconds UDC exceeds UDCSW we leave the precharge contactor energised and wait for a start signal. Once start signal is received we close the main and open the precharge contactor.

[Riwi]

Hi,

Dont know if this is the right place for this questions but I wanted to as about the max rpm that you been able to reach using the evbmw logic board and tesla large drive unit. I have see both 16000 and 18000rpm as the max rpm from tesla.

Thanks

Rikard

[Jack Bauer]

I've been to 16k. Am sure you could go higher if you wanted:)

[Riwi]

I've been to 16k. Am sure you could go higher if you wanted:)

Hey!

Thank you for your answer. I've gone through all your moving material, thanks for all you done. I'm geting a LDU unit after the summer.

As I understand it there are multiple "things" limiting the max rpm of an induction motor.
From you perspective, is there a limitation in the logical board for how high the rpm can go or is it more a motor design type limit?

Thanks again

Rikard

[etapp01@hotmail.com]

Hi!
I have a ready built board that is installed in LDU and connected to 54Volt.
I can get it into RUN and activate Forward and apply volt to the Pedal input but the motor doesn't move. I can see that the pot value changes to high value than the potmin value.
Can I expect it turn with 54Volt?
Thanks!
Peter

[Kevin Sharpe]

Can I expect it turn with 54Volt?

Yes... does this help?

viewtopic.php?f=10&t=76&p=1593#p1544

[etapp01@hotmail.com]

Well, everyting looks right (as far as I can understand) on the Web interface and I can hear the inverter work as I press the pedal but it doesn't turn.
Will continue on Tuesday night.

[Jack Bauer]

Are you selecting a direction? If you do not pull either forward or reverse lines to +12v the drive unit will sit there looking at you. don't ask me how I know:)

[etapp01@hotmail.com]

Yes, I can get it into RUN and activate Forward and apply volt to the Pedal input. I can see that the pot value changes to high value than the potmin value and the sound of the inverter respond to the throttle change...
I'm a bit puzzled.

[tom91]

Please plot the Potnom value, this should rise with the throttle position. Does the value for dir change to Foward when you pull forward high?

[etapp01@hotmail.com]

dir changes to FORWARD and at the same time lasterr changes from TORQUE to CURRENTLIMIT.
potminimun is 520 dig.
pot is following throttle from 400 to 2000 when I'm pressing it.
Will try to plot but Web interface isn't very stable...