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Discussion Starter #1
It's that time again. Time for another opensource inverter hacking project. I have returned to my roots on this occasion, BMW! The i3 inverter is going under the screwdriver. Need to get some experience with PM motors ahead of the Model 3 arriving on these shores.....annnd the fact my E39 touring started making some interesting backfiring sounds this morning. Might soon be about to loose the Jesus nut.
 

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Hi, I am interestet in your i3 project, because I maybe warnt to use an i3 motor unit for my project as well.
Is the Hybrid-Synchronmotor more difficult to control ?
Can you say when your i3 project will start probably.
 

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Weber transaxle dissassembly
https://www.youtube.com/watch?v=dqM3YXEf1js

Well since nobody is saying this...
If you got inverter and you got transaxle, batteries aside... you could use motor B to drive the wheels and just connect a Briggs&Stratton lawnmower engine to motor/generator A. Of course you would use flex coupling to dampen vibration. You simply leave clutch B off and only operate clutch A. Or weld it for that matter....

So when you run out of battery you start B&S motor and apply clutch A to bring say 8 - 10kW to inverter.
Inverter could be run off of two Lebowski brains. One only in regen mode.
Second driving motor B up to 70mph. TomDB sucessfuly operates BLDC motor using one Lebowski brain board.
http://www.diyelectriccar.com/forums/showthread.php/chevy-volt-opel-ampera-inverter-179922.html

No CAN bus needed that way and only You in control of operating B&S stinker :).

5c dropping...
 

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Of course TriPhase needs TriCore :)
Thanks to Arber I'll have a small sync motor on my desk soon. And some say a Nissan Leave drivetrain is coming my way. Let the fun begin :D
I have the motor... small gimbal Brushless Motor GBM5206-150T
http://www.himodel.com/electric/iPower_Gimbal_Brushless_Motor_GBM5206-150T.html

We made a shaft for polarized encoder magnet in center. On the other end you mount ABZ encoder chip and use it to control motor.
https://www.rls.si/en/products/rota.../rmf44-rotary-magnetic-module-on-metal-flange

On the shaft you can mount a pulley like this to small ACIM motor.
Even better would be to use another small BLDC motor and put its phase wires to 3phase bridge and a load. That way you control the load without additional complex electronics.

https://www.ebay.co.uk/itm/GT2-10mm...var=511364911881&_trksid=p2057872.m2749.l2649

I will bring motor, encoder, axle and pulley(kit) to you on my visit. You can decide on how to mount them yourself...

A
 

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Discussion Starter #9
Dug a little deeper into the i3 inverter. Not one but two tricore processors on the logic board:rolleyes:

Seems they use the same igbt driver as Tesla :
https://www.infineon.com/dgdl/Datas...c11e2&fileId=db3a304330f68606013122ce5f3649cb

700A current sensor on each phase :
http://www.lem.com/docs/products/hc5f700-s.pdf

...and I found a really cool resolver to digital converter chip :
https://www.mouser.ie/productdetail/595-pga411qpaprq1

Mrs.Bauer says I need to do something called "Resting" for the afternoon. Not sure what that is. Probably another word for work on ev stuff.
 

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Dug a little deeper into the i3 inverter. Not one but two tricore processors on the logic board:rolleyes:

Seems they use the same igbt driver as Tesla :
https://www.infineon.com/dgdl/Datas...c11e2&fileId=db3a304330f68606013122ce5f3649cb

700A current sensor on each phase :
http://www.lem.com/docs/products/hc5f700-s.pdf

...and I found a really cool resolver to digital converter chip :
https://www.mouser.ie/productdetail/595-pga411qpaprq1

Mrs.Bauer says I need to do something called "Resting" for the afternoon. Not sure what that is. Probably another word for work on ev stuff.
Seems to me that this controller is based on same Open Source kit as I have been using, the Infineon Hybrid kit Pack
https://www.infineon.com/dgdl/Infin...n.pdf?fileId=db3a30432239cccd01225a7cfb166c8a

The only difference is the version (they have been using the Pack2) , while I have used the basic kit. I knew they were using it for development, funny to see this in the final product. At least it is completely open source, both the board and most of the code.
 

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Discussion Starter #12
Decided I wanted to do some reverse engineering today. Jeez what a bad idea. The Tesla inverter igbt drivers took an hour or two to work out. Nice and simple and intuitive. Not so my favorite auto maker. Looks like the kids were let off to play with no adult supervision. We got SPI ADCs , high speed digital isolators , different grounds , 32v dc supply requirement and a real fun HVDC derived power supply using a Viper16.

Oh yeah and the idc connectors used in this thing are all unobtanium from a company called ERNI. Good news is I have woken up the gate drivers and their power supplys so some more pain and we should be switching the big igbt. Remember kids, try this at home so I don't have to!
 

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Annnd we have lift off. All 6 igbts firing and current sensors reading. Needs ground, +5v (one for igbt logic and one for current sense) , +32v for igbt drive , one +5v enable signal for the dc dc power supply and then 6 3v3 or 5v signals to turn on each igbt. Fault lines tbd. Current sensors are analog out.
 

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Discussion Starter #16
Hmmm this sounds suspicious.....
Just one question: Does it work with 24V instead of the 32V?
Nope. And the secondary outputs are proportional to the input. 32v in gives +15v and -8v. 31v in gives 14v and -7v.
 

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Nope. And the secondary outputs are proportional to the input. 32v in gives +15v and -8v. 31v in gives 14v and -7v.
Ok for the Infineon driver modules I know and I am quite sure BMW is using the normal Drive voltage Level at the output is -8 -> +15V. In my case it is realised with a supply voltage about 12V (can be 8-18V according to specs but is really 10-16V)

The only reason using a higher Voltage as I see it would be if there is a massive cooling unit (fan or pump) in the 32V circuit. I would expect this Unit to take 16V and leave 16V for the drive unit. The 32V could come from a DC/DC -converter.
But BMW might have other thoughts...:)
 

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Finally found a connector that will at least fit the pins of the unobtanium BMW i3 igbt driver board ribbon cable plug. Time to go design a logic board.

At this time I will not be making the design open source. This may change in the future but in light of recent events and the actions of a small number of individuals I have taken this decision. I hope people will understand.
 

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I fully support that.

Let me enlighten you a bit. A certain individual contacted me and wanted to talk me into some sort of cooperation with vague promises. He then tried to persuade me to persuade Damien to lower the price for the Tesla boards (because of the awesome cooperation).
He threatened that he had alternative sources (oh really?! the project is open source, what a surprise you have alternative sources!) and would make use of them.

Next thing he was convinced that the price included Damien de-soldering the current sensors on the small drive unit and fitting the new board. "I've seen it on the video, it only takes 20 minutes!". So again he used Damiens freely shared information to pit it against us. And he kept me on the phone for hours with his bullshit.

This experience (and a few others) also make me consider to stop sharing freely and only give access to a selected crowd with proven moral integrity.

On to the good sides I have been donated a complete Nissan Leaf Drive Train. One of the clear upsides of sharing freely!
 
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