Prius Gen3 Inverter Hacking

[Jack Bauer]

So made an interesting find. It would seem that ALL the modern Toyota hybrid range of inverter/converters use the same synchronous serial interface for control as the Lexus GS450H. Now the commands will probably be different but the hardware would be the same opening the door to using these inverters and transaxles as is without the need for a new logic board.

Obvious caveats would be :
1)Need to use the inverter with the transmission it was designed for.
2)assuming the inverters are as "dumb" as the Lexus and don't care about voltage etc they just make torque when commanded to do so.
3)need to capture data from as many vehicles as possible eg. prius gen3, rav4h,is300h etc

[Bigpie]

Is it a standard protocol like SPI or I2C?

[johnspark]

So made an interesting find. It would seem that ALL the modern Toyota hybrid range of inverter/converters use the same synchronous serial interface for control as the Lexus GS450H. Now the commands will probably be different but the hardware would be the same opening the door to using these inverters and transaxles as is without the need for a new logic board.

Obvious caveats would be :
1)Need to use the inverter with the transmission it was designed for.
2)assuming the inverters are as "dumb" as the Lexus and don't care about voltage etc they just make torque when commanded to do so.
3)need to capture data from as many vehicles as possible eg. prius gen3, rav4h,is300h etc

Good, well i will be doing the AVV50L/R one. I have hardly touched the Prius 3 inverter, so perhaps i can just power up and look at the signals with aPicoscope?

[Bigpie]

Is the idea that those of us that are awaiting a board would now get one that sends the commands to the unmodified inverter? Would we need to use a gen 3 transaxle with it?

[Jack Bauer]

I'm getting new rev Johannes / blue pill boards made and investigating if I can get a comms capture from a gen 3 prius.

[Bigpie]

I'm pretty easy either way. Unfortunately I don't know anyone with a Prius to help grab a capture.

[bones]

Hey Damien, I am building a Prius Gen 3 V1 board. This is the most challenging board I have attempted to populate myself, but I was pleasantly surprised how well it turned out (so far). I got boards made and a stencil for solder paste, put the paste on the board, and placed the surface mount parts by hand. Put it in a reflow oven at work. The result looks great , and not as hard as I feared. Next is the through hole parts...

I have two questions:

1) What is the part number for the WiFi mini boards? They are not on the BOM.
2) where can I get the software for the V1 boards? Is there a special version somewhere?

Thanks,
Bones

[arber333]

Hi Damien

I am looking at my charger board and the space inverter has left above driver board. I see it is possible to stretch the board quite a bit if we design a hole for the small cable to get through. There is plenty of space left inside. So then using simpler Blue pill chips instead those pesky Q44s would be possible then.

[Jack Bauer]

No special software. Wifi modules available from Johannes via the openinverter shop.

Nice work Arber.

[Stephen Darbey]

Hi Damien.

If you still need a comms capture from a Prius, just shout, any evening late in week or first thing on a sat morning.

Regards
Stephen

[Stephen Darbey]

Actually. I will plug in my laptop with some software that I acquired and see what reporting details I can export and send on.

will revert

regards
Stephen

[Jack Bauer]

Thanks Stephen, much appreciated.

[Jack Bauer]

I'd like to give everyone a much overdue update on the Prius logic board situation. In short, we have a new board and new supply coming on stream. Boards will be available soon (including to those who have been waiting a long time!). The video here gives a full explanation and I expect to be using JLCPCB for all my builds if things go to plan. So, more boards, faster and cheaper:)

[martii]

Finally, I see v5 of Tesla Gen2 charger will ditch this expensive hard to get microcontroller in favour of STM32 - great move. Are you going to publish those on your github? Did you also choose USB-C? Also battery connector - so we'll be able to have charging times table? Cool!

[johu]

That is really good news! I guess I'll try my hand at a V3 control board.
Did you post the jlcpcb bom on github?

[martii]

It looks like Damien is too busy to update github at the moment

[Jack Bauer]

New Gen 3 prius board in production at JLC:)

[martii]

Looks like this one has so less components - I'm using JLC for at least a year now - they've been great so far. Good choice.

[Mouse]

That's an awesome combination of features.
Not sure if I'm going to regret getting a Yaris inverter because it was very cheap.

[MattsAwesomeStuff]

Between the success of the GS450 and the compact SMT of the Prius Gen3... looks again like I picked the wrong horse in going with the through-hole Prius Gen 2. Oh well, might be something I upgrade to later, if the Gen 3 is where the priority is getting new features online like the Boost-As-Battery-Charger and such. Exciting times.

[PatrykS]

New Gen 3 prius board in production at JLC:)

It doesn't look like matching PriusG3_V2 schematic you published earlier - no STM32 (Blue Pill) modules, and just one motor control?

[Dilbert]

Im looking to see what the difference between the gen 2 and gen 3 Prius transaxle motors are, I know there is slightly different power outputs, but do the motors have the same number of poles etc? Considering trying to drive my gen 2 transaxle off a stock gen 3 inverter. I know changing the control board in the inverter to the open source one is one potential solution.

[Jack Bauer]

Looking on page 223 of the gen3 wiring diagram shows the exact same synchronous serial over can as used by the gs450h inverter. Now we just need the data from a running gen3 prius:)

[Dilbert]

Yea I spotted the signals were the same. I have a hybrid auris sitting in my drive, I believe it’s identical to the gen 3 Prius, so can log any data we need.

My logic analyser is quite old, but I should be able to make up something with an stm32 to log both sides of the communication. I actually have the due running the gs450h code on my desk, so I can use this to test my logger.

Obviously we need frames at idle, to check data lengths, check sums. Then maybe some frames driving in EV mode and possible engine start, should see mg1 starting engine.

[Mouse]

It doesn't look like matching PriusG3_V2 schematic you published earlier - no STM32 (Blue Pill) modules, and just one motor control?

I've watched the recent video that goes with the board release and it's an interesting combination of features that will be ideal for a lot of conversions. Which is MG2 control using a STM32 and high capacity battery charging using MG1 as a 3 phase rectifier and the buck/boost circuit for controlling charge current. Which is exactly the sort of combination I was hoping would work for my light weight project so I'm glad this has been produced.

I also don't think there's the real need for the Blue Pill modules any more now he's using cheap SMD assembly service. However I really like the idea of using the Blue Pill.