openinverter forum

Sorted, was missing 0x288

So we completed our journey yesterday and it was 4250 km. I used the apps to reconstruct the energy used off payed chargers and my faint memory for all others:

• Payed kWh: 376
• Free kWh: 297 (94 from free fast chargers, others from Schuko)
• Total kWh: 673
• Average consumption: 158 Wh/km

The car held up very well, only damage was the smashed battery under cover caused by a rock on a gravel road. I had some rapidgating problems when doing more than 2 full quick charges per day. Also while driving in heavy rain the LBC went crazy and suddenly commanded a 25 kW discharge and 13 kW charge power limit despite the battery not overheating. Not sure what exactly happened there but the problem went away after everything had dried.
Also poor mans charger died a couple of times limiting overnight charging.

I really have to do something about waterproofing and rock proofing my battery pack. Folded 1mm sheet metal is one idea. And I should add a fan to provide at least a bit of cooling. Not great, but least effort.

Finally adding a Prius inverter to handle quick AC charging would greatly improve autonomy in the situation where you can't rely on fast chargers.

I made some video shots on our way back, so video is coming

Efacec!!!!

Well that's a road test and a half. That average consumption is very encouraging as well!

Really good draw test. I am impresed that with OEM transmission and its gears you can get such good results.

Yes I'm quite pleased myself, provided I haven't done any mistakes summing up the charge sessions.

On our way back I could confirm that going 110 km/h on Swedish roads takes like 190 Wh and on German roads only 170 Wh. Must be the rough surface.

johu wrote: ↑Tue Aug 17, 2021 10:11 am Yes I'm quite pleased myself, provided I haven't done any mistakes summing up the charge sessions.

On our way back I could confirm that going 110 km/h on Swedish roads takes like 190 Wh and on German roads only 170 Wh. Must be the rough surface.

True, i noticed mysef higher draw on some older highways versus newly paved ones. Things really get tough if there is water on the road.
I bet your drag will improve if you add underbody panel. Maybe you could improve your Cd further if you add rubber skirt to your front bumper. I see our Ampera has a skirt from OEM.

Yes the underbody is rather flat. I have closed off the exhaust tunnel and fuel tank area where the battery pack is. The battery pack slopes downwards though, I bet that's not ideal but I can't do anything to change that.
Rubber skirt sounds interesting. VW mounted some sophisticated plastic skirt already, not sure what it does

On Ampera it is a rather sacrificial skirt which scrapes on everything that is a little higher than the road. It is mounted under bumper plastic and spanning from one wheel well to another.
I am also thinking of adding a skirt to my pug.
My intention is to use one 25x25mm alu angle and cut it several times so i can shape it to bumper underside. Then i would rivet rubber skirt to vertical angle surface. Horizontal will be fastened under the bumper.

Mounted a Gen3 inverter on top of the Leaf inverter. Currently I'm only using the DC/DC converter but will use it for 3-phase charging and for providing 230V AC.

It runs a dual motor board that I modified a bit:

• DC/DC converter voltage mod so it runs off 400V
• Pulled up IGCT with 560R and pulling that down with the precharge pin, so DC/DC is enabled when precharge drops out
• Soldered another CAN transceiver on top of the existing one to have MG2 CPU on the CAN bus (up until now I didn't realize it has no external connection)
• Changed the firmware to enable precharge in the bootloader and to drop it out after some delay after entering run mode

Now I need to close off the various holes and mount the logic connector properly. Will probably use a much smaller one as I only need 12V, CAN and the EVSE signals.

Interesting. I would love to get my Prius Gen2 convertor to run MG1 and Mg2 AND do charging..

johu wrote: ↑Sun Aug 22, 2021 9:37 am Mounted a Gen3 inverter on top of the Leaf converter. Currently I'm only using the DC/DC converter but will use it for 3-phase charging and for providing 230V AC.

You think we could also use Gen2 as a charger?

arber333 wrote: ↑Sun Aug 22, 2021 11:28 am You think we could also use Gen2 as a charger?

Yes, just as well.
Running 2 motors AND do charging would require a separate rectifier

johu wrote: ↑Sun Aug 22, 2021 12:07 pm

arber333 wrote: ↑Sun Aug 22, 2021 11:28 am You think we could also use Gen2 as a charger?

Yes, just as well.
Running 2 motors AND do charging would require a separate rectifier

No it will be 3phase charging only application. Do you think it could be done solely with your control board? Or woud charging require more changes?

I am thinking of putting Gen2 inverter under the rear seats on the rght side where i had one of Outlander chargers now. It is of a good profile to fit under rear seats and mounting points are simple sheet metal which will allow me to fasten it in the same way...
Anyone have any outside measurements for Gen2 inverter? I dont have it here yet.

johu wrote: ↑Sun Aug 22, 2021 9:37 am

• Soldered another CAN transceiver on top of the existing one to have MG2 CPU on the CAN bus (up until now I didn't realize it has no external connection)

Any pics of this?

arber333 wrote: ↑Sun Aug 22, 2021 2:04 pm Anyone have any outside measurements for Gen2 inverter? I dont have it here yet.

Roughly 50cm front to back on the longest side and about 40 cm wide including the water reservoir on the side. About 23cm high.

arber333 wrote: ↑Sun Aug 22, 2021 2:04 pm No it will be 3phase charging only application. Do you think it could be done solely with your control board? Or woud charging require more changes?

I am thinking of putting Gen2 inverter under the rear seats on the rght side where i had one of Outlander chargers now. It is of a good profile to fit under rear seats and mounting points are simple sheet metal which will allow me to fasten it in the same way...
Anyone have any outside measurements for Gen2 inverter? I dont have it here yet.

Short answer: yes it can be done solely with the Prius board
Long answer
viewtopic.php?f=14&t=1070

chrskly wrote: ↑Sun Aug 22, 2021 3:42 pm Any pics of this?

No, forgot. Well next time I take the cover off. Removed some 0 ohm resistor and soldered a write to RX and TX. The transceiver literally sits on top of the existing one and connects to pins 2, 3 (power) and 6, 7 (canh, canl)

Made another bracket and closed off the connector holes. Will put cable glands in there later and some seals as it's not yet waterproof.

Drove 200km without charging today and arrived with 23% left quite low consumption also, I was going 100 km/h most of the time

Thats cool range!

Killed the 2nd Prius 3 inverter today

It has worked like a champ for DC/DC converting.

So today I was getting ready to test the charging. Did another firmware upgrade on the atmega with HV OFF. Then unplugged the FTDI cable, turned on high voltage, plugged in FTDI and watched diagnostic messages scroll by. All good so far. Now I was going to do some more wiring, so I closed the terminal (Arduino built in) and in that very instant a very unpromising sound emerged from the inverter. Yes, another fuse blown and I couldn't be bothered to check any further.

So I'm definitely leaving the Prius/Atmega route. I'll put the Ampera DC/DC converter back in and then see what I do next.

As a "bonus" my contactors are now welded, not sure how thats related though as they were already on when the explosion happened. Joy.

EDIT: just learned that Arduino cycles through the boot loader once you close the terminal. What a great idea I certainly won't expose any more power electronics to it.

At this rate I don't really understand how my prius gen3 inverter is still alive Right at this moment it's pulling 3x12A from my father-in-law's garage. I suppose I have enough experience with Arduinos to have developed an instinct to not plug in USB while anything is happening. I don't think anything happens when you unplug USB though?

Anyway, it sounds like the board really needs at least some sort of pulldown resistors or maybe an AND gate connected to the AVR's reset line or something.

When monitoring using arduino IDE I only connect rx/tx and gnd to avoid unwanted resets.

bexander wrote: ↑Fri Sep 17, 2021 6:13 pm When monitoring using arduino IDE I only connect rx/tx and gnd to avoid unwanted resets.

Alright I see. I use one of those ready-made FTDI cables.

celeron55 wrote: ↑Fri Sep 17, 2021 6:00 pm At this rate I don't really understand how my prius gen3 inverter is still alive Right at this moment it's pulling 3x12A from my father-in-law's garage. I suppose I have enough experience with Arduinos to have developed an instinct to not plug in USB while anything is happening. I don't think anything happens when you unplug USB though?

Anyway, it sounds like the board really needs at least some sort of pulldown resistors or maybe an AND gate connected to the AVR's reset line or something.

Yes some extra hardware is obviously needed, it's hard to use in its current state.

I also use a ready-made FTDI cable but I connect an adapter in between when monitoring.

If you are truly giving up on the Prius charger, you might consider the Flatpack option? 7 FP in series will provide 21kW of charging power for 96S