[DRIVING] Audi A2 /w Prius Gen2 Transaxle & Inverter  [FINISHED]

Tell us about the project you do with the open inverter
Post Reply
User avatar
johu
Site Admin
Posts: 5683
Joined: Thu Nov 08, 2018 10:52 pm
Location: Kassel/Germany
Has thanked: 153 times
Been thanked: 960 times
Contact:

Re: Audi A2 /w Prius Gen2 Transaxle & Inverter

Post by johu »

Connected the resolver today.
- R1 to MRF
- R2 to MRFG
- S1S4 to MCSG and MSNG
- S2 to MSN
- S3 to MCS

Turns out with that mapping you have to set pinswap from 5 to 7 (swap resolver sin/cos). So with S2 on MCS and S3 on MSN you'd not need that swap. Anyway, motor turns happily now, of course forward and reverse are also swapped.
Support R/D and forum on Patreon: https://patreon.com/openinverter - Subscribe on odysee: https://odysee.com/@openinverter:9
User avatar
johu
Site Admin
Posts: 5683
Joined: Thu Nov 08, 2018 10:52 pm
Location: Kassel/Germany
Has thanked: 153 times
Been thanked: 960 times
Contact:

Re: Audi A2 /w Prius Gen2 Transaxle & Inverter

Post by johu »

Trying to run the DC-DC converter now. Unfortunately it's not quite as straight forward as I though.
I am running the buck converter to produce about 230V on the DC-DC input. I hooked up IGCT to "ignition" 12V. When done that way, the DC-DC converter does not start up. It first wants to see some high voltage then IGCT.

Now I could simply add an RC lowpass to delay IGCT. Or produce another signal in the VCU
Support R/D and forum on Patreon: https://patreon.com/openinverter - Subscribe on odysee: https://odysee.com/@openinverter:9
User avatar
johu
Site Admin
Posts: 5683
Joined: Thu Nov 08, 2018 10:52 pm
Location: Kassel/Germany
Has thanked: 153 times
Been thanked: 960 times
Contact:

Re: Audi A2 /w Prius Gen2 Transaxle & Inverter

Post by johu »

Fuse arrived today. Bolted it directly onto the contactor and, lucky me, I just needed to add an isolated standoff to one of those battery mounting studs
Attachments
IMG_20220315_131905.jpg
Support R/D and forum on Patreon: https://patreon.com/openinverter - Subscribe on odysee: https://odysee.com/@openinverter:9
RetroZero
Posts: 702
Joined: Tue Oct 29, 2019 2:48 pm
Location: France
Has thanked: 311 times
Been thanked: 38 times
Contact:

Re: Audi A2 /w Prius Gen2 Transaxle & Inverter

Post by RetroZero »

I can't wait for you to find the magical solution to using AC output for charging. 😉
I will hopefully go back to Mg1 solution for now
User avatar
johu
Site Admin
Posts: 5683
Joined: Thu Nov 08, 2018 10:52 pm
Location: Kassel/Germany
Has thanked: 153 times
Been thanked: 960 times
Contact:

Re: Audi A2 /w Prius Gen2 Transaxle & Inverter

Post by johu »

Yes that will be one of the next tasks! Already tested with lab power supply.

Today I did direction selection. Found it kind of pointless to have a "Neutral" so the buttons are working as follows:

- Inverter starts up in neutral
- When pressing brake and forward it will go into forward direction, vice versa for reverse
- When already in drive mode, pressing forward again will increase regen (4 levels, level 0 means off)
- N button decreases regen
- R button only changes into reverse when pressing brake and motor is below 100 rpm (logic of inverter)

The rev counter sits at 3000 rpm in idle and moves to higher speed when requesting power and to lower speed when regenning (proportional to DC current). When changing regen level it displays that for 1 second, 1000=level0, 4000=level3. Can't go to 0 as that would disable power steering.

Direction selection is done via resistor ladder on mprot input. Less wires to route. Actually I'm using the wire harness from the second lambda sond (4 wires). 12V, ladder, OC forward, OC reverse
Attachments
IMG_20220317_151808.jpg
Support R/D and forum on Patreon: https://patreon.com/openinverter - Subscribe on odysee: https://odysee.com/@openinverter:9
User avatar
Zapatero
Posts: 443
Joined: Fri Oct 25, 2019 11:08 am
Location: Germany, Ulm
Has thanked: 25 times
Been thanked: 39 times
Contact:

Re: Audi A2 /w Prius Gen2 Transaxle & Inverter

Post by Zapatero »

The neutral would only make sense of it would be like a parking position where the spline in the gearbox engages. Do you reuse that function?
User avatar
johu
Site Admin
Posts: 5683
Joined: Thu Nov 08, 2018 10:52 pm
Location: Kassel/Germany
Has thanked: 153 times
Been thanked: 960 times
Contact:

Re: Audi A2 /w Prius Gen2 Transaxle & Inverter

Post by johu »

No, I don't have the servo motor and even if I did it probably wouldn't fit (firewall in the way)
Support R/D and forum on Patreon: https://patreon.com/openinverter - Subscribe on odysee: https://odysee.com/@openinverter:9
arber333
Posts: 3241
Joined: Mon Dec 24, 2018 1:37 pm
Location: Slovenia
Has thanked: 74 times
Been thanked: 223 times
Contact:

Re: Audi A2 /w Prius Gen2 Transaxle & Inverter

Post by arber333 »

johu wrote: Thu Mar 17, 2022 3:06 pm Today I did direction selection. Found it kind of pointless to have a "Neutral" so the buttons are working as follows:

- Inverter starts up in neutral
- When pressing brake and forward it will go into forward direction, vice versa for reverse
- When already in drive mode, pressing forward again will increase regen (4 levels, level 0 means off)
- N button decreases regen
- R button only changes into reverse when pressing brake and motor is below 100 rpm (logic of inverter)
For more ideas...
I just use a single latching switch with LED wired to reverse side. I use it in position Forward without LED and in Reverse with LED lit.
I simply use a series of relays to toggle ATX computer pins in predetermined way to show the car orientation on the dash.
So when i turn the key to 2nd position i get P illuminated.
When i apply start i get D illuminated.
If i toggle reverse i get R illuminated.
N is not affected by any position as the car is allways in neutral and i have to use handbrake to keep it on an incline.
Yes the brake interlock at start is active through the ATX computer pins. TUV Sud was content with implementation.

Photos of installation...
[/attachment]
20220312_142020.jpg
20220317_215024.jpg
User avatar
johu
Site Admin
Posts: 5683
Joined: Thu Nov 08, 2018 10:52 pm
Location: Kassel/Germany
Has thanked: 153 times
Been thanked: 960 times
Contact:

Re: Audi A2 /w Prius Gen2 Transaxle & Inverter

Post by johu »

I see, so you're using the key switch to go straight into Run mode and forward. Reverse switch toggles reverse. Not bad also.
I basically don't use the key switch for starting, but the VCU sends the start signal to inverter once BMS and inverter voltage match.

I now also consider to make N button disable regen completely so its label makes a bit more sense. Then by pressing forward multiple times regen can be adjusted up again.

I also consider mapping cruise control on there as the car doesn't have the lever. Maybe pressing reverse for 1s could set cruise speed, thereafter pressing reverse again would decrease speed and pressing forward would increase speed. Pressing N or brake pedal would cancel cruise control
Support R/D and forum on Patreon: https://patreon.com/openinverter - Subscribe on odysee: https://odysee.com/@openinverter:9
RetroZero
Posts: 702
Joined: Tue Oct 29, 2019 2:48 pm
Location: France
Has thanked: 311 times
Been thanked: 38 times
Contact:

Re: Audi A2 /w Prius Gen2 Transaxle & Inverter

Post by RetroZero »

johu wrote: Thu Mar 17, 2022 3:06 pm
Today I did direction selection. Found it kind of pointless to have a "Neutral" so the buttons are working as follows:

- Inverter starts up in neutral
- When pressing brake and forward it will go into forward direction, vice versa for reverse
- When already in drive mode, pressing forward again will increase regen (4 levels, level 0 means off)
- N button decreases regen
- R button only changes into reverse when pressing brake and motor is below 100 rpm (logic of inverter)
Direction selection is done via resistor ladder on mprot input. Less wires to route. Actually I'm using the wire harness from the second lambda sond (4 wires). 12V, ladder, OC forward, OC reverse
Like what you have done.
arber333
Posts: 3241
Joined: Mon Dec 24, 2018 1:37 pm
Location: Slovenia
Has thanked: 74 times
Been thanked: 223 times
Contact:

Re: Audi A2 /w Prius Gen2 Transaxle & Inverter

Post by arber333 »

johu wrote: Fri Mar 18, 2022 7:03 am I see, so you're using the key switch to go straight into Run mode and forward. Reverse switch toggles reverse. Not bad also.
I basically don't use the key switch for starting, but the VCU sends the start signal to inverter once BMS and inverter voltage match.
You have inverter setup a bit differently. Maybe you could use N pin as Notaus? You think your TUV would agree?
I also considered using N as a button, but i found out that Notaus is perfect for the job. I just never considered showing the N on the dash. It would require a lot of elaborate relay circuit. Hm... maybe it would be a good thing to have visual ID when notaus is pressed.
I have my inverter setup so it will pull controler enable pin to GND and this trips it unconscious. I use Notaus also with my Arduino DUE to disable inverter when charging.
User avatar
johu
Site Admin
Posts: 5683
Joined: Thu Nov 08, 2018 10:52 pm
Location: Kassel/Germany
Has thanked: 153 times
Been thanked: 960 times
Contact:

Re: Audi A2 /w Prius Gen2 Transaxle & Inverter

Post by johu »

No Notaus for me, never really understood the point to be honest. Turn key off -> Notaus. It is not required to have it, consequently no production car has it.

Today I worked on charging. Put together a DIN rail assembly
1. GFCI
2. Some terminal blocks
3. Charge enable relay, powers up the car, inverter etc.
4. AC relay
5. DC relay (also controlled by DC relay output of inverter). Enables the larger AC relay and also the DCDC enable signal

So now also the DC-DC enable problem is solved.

Charging via my lab supply worked flawlessly, basically pulled out the rectifier input from the AC relay and connected the 60V/16A lab supply instead. Then let the circuitry to its job. Worked.

Then I rigged up actual AC via a cooker element. The whole thing powered up but strange noises came from the inverter and smoke come from the heating element. Oh. Pulled out the plug, still smoking. Argh, DC came out from the A/C inverter and backpowered. Disconnected the cooker and finally everything switched off.
Next I tested connecting lab supply again. In one polarity it is a short. In the other polarity it seemed ok. So tried charging from the lab supply again resulting in a "bonk" from the inverter and power supply going into over voltage protection.
Next I checked that everything else still worked which thankfully it still did.

So either the rectifying diodes were overloaded or the A/C inverter actually tries doing something funky when it sees voltage on its output. Either way, I will replace those IGBTs with a proper bridge rectifier and try that.

Oh and one more thing: replaced the heavy lead battery by a lighter LFP battery and relocated to the front.
Attachments
IMG_20220318_173859.jpg
Support R/D and forum on Patreon: https://patreon.com/openinverter - Subscribe on odysee: https://odysee.com/@openinverter:9
arber333
Posts: 3241
Joined: Mon Dec 24, 2018 1:37 pm
Location: Slovenia
Has thanked: 74 times
Been thanked: 223 times
Contact:

Re: Audi A2 /w Prius Gen2 Transaxle & Inverter

Post by arber333 »

johu wrote: Fri Mar 18, 2022 5:01 pm No Notaus for me, never really understood the point to be honest. Turn key off -> Notaus. It is not required to have it, consequently no production car has it.
See those are the differences between regulation interpretations i was talking about. With me TUV sud required notaus button. So i selected the smallest i could get 😎.
User avatar
johu
Site Admin
Posts: 5683
Joined: Thu Nov 08, 2018 10:52 pm
Location: Kassel/Germany
Has thanked: 153 times
Been thanked: 960 times
Contact:

Re: Audi A2 /w Prius Gen2 Transaxle & Inverter

Post by johu »

wow :) In exchange they did a noise test on both my conversions... On yours also?
Support R/D and forum on Patreon: https://patreon.com/openinverter - Subscribe on odysee: https://odysee.com/@openinverter:9
arber333
Posts: 3241
Joined: Mon Dec 24, 2018 1:37 pm
Location: Slovenia
Has thanked: 74 times
Been thanked: 223 times
Contact:

Re: Audi A2 /w Prius Gen2 Transaxle & Inverter

Post by arber333 »

johu wrote: Fri Mar 18, 2022 5:40 pm wow :) In exchange they did a noise test on both my conversions... On yours also?
No surprisingly not. But the car is year 2000 and there might not be a requirement so far back.
Also i saw motor inverter combo slid through administrative cracks 😁. Even though they said different motor inverter combos require EMC testing they forgot to request it. Though i declared the differences. Dodged the bullet there...
User avatar
geduxaz
Posts: 125
Joined: Wed Jun 23, 2021 7:00 am
Has thanked: 3 times

Re: Audi A2 /w Prius Gen2 Transaxle & Inverter

Post by geduxaz »

Any test drives? I still get that resistance from motor when trying to coast and get shaking before stopping.
User avatar
johu
Site Admin
Posts: 5683
Joined: Thu Nov 08, 2018 10:52 pm
Location: Kassel/Germany
Has thanked: 153 times
Been thanked: 960 times
Contact:

Re: Audi A2 /w Prius Gen2 Transaxle & Inverter

Post by johu »

No driveshafts yet...
I think the shaking could be caused by the inverter hardware. When commanding low amplitude it simply outputs 50/50 duty cycle which essentially shorts out the motor shortly before stopping. Maybe brkrampstart gets around this. Also try setting curkifrqgain=0 and lower curki. It was mentioned with a Gen3 transaxle and apparently helped.

EDIT: look here: viewtopic.php?p=38034#p38034
Support R/D and forum on Patreon: https://patreon.com/openinverter - Subscribe on odysee: https://odysee.com/@openinverter:9
User avatar
johu
Site Admin
Posts: 5683
Joined: Thu Nov 08, 2018 10:52 pm
Location: Kassel/Germany
Has thanked: 153 times
Been thanked: 960 times
Contact:

Re: Audi A2 /w Prius Gen2 Transaxle & Inverter

Post by johu »

I have charging worked out now. Works a treat when replacing the IGBTs in the A/C inverter by a simple rectifier.

The power factor leaves something to be desired and I have to check what happens when the car is still turned on and then plugged in.

The reason for poor power factor is most likely a slow current sensor. It adds too much phase shift so the P-controller tries to counteract current that is no longer there or fails to compensate for current that is already there. I can still charge at roughly 3 kW, so might just leave it like that.
Support R/D and forum on Patreon: https://patreon.com/openinverter - Subscribe on odysee: https://odysee.com/@openinverter:9
User avatar
geduxaz
Posts: 125
Joined: Wed Jun 23, 2021 7:00 am
Has thanked: 3 times

Re: Audi A2 /w Prius Gen2 Transaxle & Inverter

Post by geduxaz »

johu wrote: Sun Mar 20, 2022 8:50 pm No driveshafts yet...
I think the shaking could be caused by the inverter hardware. When commanding low amplitude it simply outputs 50/50 duty cycle which essentially shorts out the motor shortly before stopping. Maybe brkrampstart gets around this. Also try setting curkifrqgain=0 and lower curki. It was mentioned with a Gen3 transaxle and apparently helped.

EDIT: look here: viewtopic.php?p=38034#p38034
i just bought "real" EV (Nissan Leaf). Now i know how should feel factory EV and what goals should be reached :D
User avatar
johu
Site Admin
Posts: 5683
Joined: Thu Nov 08, 2018 10:52 pm
Location: Kassel/Germany
Has thanked: 153 times
Been thanked: 960 times
Contact:

Re: Audi A2 /w Prius Gen2 Transaxle & Inverter

Post by johu »

Oh yes, I'm always quite jealous when I drive my fathers e-Golf! It is so quiet, the ICE transmission in Touran is super noisy. I hope this improves with Prius transmission
Support R/D and forum on Patreon: https://patreon.com/openinverter - Subscribe on odysee: https://odysee.com/@openinverter:9
arber333
Posts: 3241
Joined: Mon Dec 24, 2018 1:37 pm
Location: Slovenia
Has thanked: 74 times
Been thanked: 223 times
Contact:

Re: Audi A2 /w Prius Gen2 Transaxle & Inverter

Post by arber333 »

johu wrote: Mon Mar 21, 2022 7:45 pm Oh yes, I'm always quite jealous when I drive my fathers e-Golf! It is so quiet, the ICE transmission in Touran is super noisy. I hope this improves with Prius transmission
Well i must say lately i dont look forward to driving my Mazda anymore. Pug is so much sleeker and smoother to drive.
But i still have Outlander rear motor and inverter. I could go and tinker with Mazda some more...

I advise you to drop the tranny and switch to OEM gearbox.
User avatar
Zapatero
Posts: 443
Joined: Fri Oct 25, 2019 11:08 am
Location: Germany, Ulm
Has thanked: 25 times
Been thanked: 39 times
Contact:

Re: Audi A2 /w Prius Gen2 Transaxle & Inverter

Post by Zapatero »

geduxaz wrote: Mon Mar 21, 2022 6:04 pm
i just bought "real" EV (Nissan Leaf). Now i know how should feel factory EV and what goals should be reached :D
I had a Nissan leaf, too. It drove great but the car itself was terrible. Now I have an ioniq and it's a million times better
User avatar
Zapatero
Posts: 443
Joined: Fri Oct 25, 2019 11:08 am
Location: Germany, Ulm
Has thanked: 25 times
Been thanked: 39 times
Contact:

Re: Audi A2 /w Prius Gen2 Transaxle & Inverter

Post by Zapatero »

arber333 wrote: Mon Mar 21, 2022 9:34 pm

I advise you to drop the tranny and switch to OEM gearbox.
Totally agree
I would not go any other route again. That's why the Subaru Impreza gets 2 OEM EV gearboxes with the OEM motors. It's gonna be so much better considering noises of the drive train and smootheness compared to my GT86.
User avatar
johu
Site Admin
Posts: 5683
Joined: Thu Nov 08, 2018 10:52 pm
Location: Kassel/Germany
Has thanked: 153 times
Been thanked: 960 times
Contact:

Re: Audi A2 /w Prius Gen2 Transaxle & Inverter

Post by johu »

Put all the charging switchgear into a box.

Next I installed the A/C pipes from cabin to dryer and radiator. They actually fit rather well!

Then tried a test fit of the Audis front assembly. While it fits by itself it doesn't fit with the fan installed. The transmission sits too far forward. So need to do something about that fan, maybe a smaller one will do (it only runs A/C).

Also it seems the A/C pipes from dryer to compressor might not clear the transmission. I currently don't have them here, will see later.
Attachments
IMG_20220320_103445.jpg
IMG_20220322_180615.jpg
IMG_20220322_180606.jpg
IMG_20220320_103446.jpg
Support R/D and forum on Patreon: https://patreon.com/openinverter - Subscribe on odysee: https://odysee.com/@openinverter:9
User avatar
geduxaz
Posts: 125
Joined: Wed Jun 23, 2021 7:00 am
Has thanked: 3 times

Re: Audi A2 /w Prius Gen2 Transaxle & Inverter

Post by geduxaz »

How you are planning to run cooling system?
Pump always on?
Front radiator or cabin heater?
Any switch between cabin/front radiator?

Also please advice. Run with my 80s pack and go for custom BMS/Charger or buy full Leaf pack and use its BMS and maybe Leaf charger (6.6kW).
Post Reply