openinverter forum

I like to convert an old VW T2b Westfalia with a rear SDU from Tesla. I’m located in Switzerland and the regulations allow 20+ HP without test approval and there’s an approval from Cagero in Switzerland for 119 hp. Both values are below the power output from the SDU. Can I limit only the throttle max value or is it possible to also set a power/ torque curve?
Switzerland’s approved test Centers are very restrictive on the regulation side and follow the UN ECE regulations and the national regulations on modifications. I need to make sure that all is correct. Any documentation on this issue or a video showing these settings?

Check the wiki. it’s an open inverter board, same brain for every inverter, just tuned differently for each motor. Open up the web interface and adjust from there.

Bratitude wrote: ↑Sun Mar 08, 2020 4:13 pm Check the wiki. it’s an open inverter board, same brain for every inverter, just tuned differently for each motor. Open up the web interface and adjust from there.

I’m currently in the planning phase, selecting the components to get in touch with the test agency for a first talk. My question is only about “is it possible”. No SDU here and no inverter board. I can’t test it, I appreciate any proof with a Video/ Screenshot.

If torque reduction is not possible I need to go ahead with a Leaf Motor (loser power rating) and the open inverter board.

Gaston wrote: ↑Sun Mar 08, 2020 5:27 pm

Bratitude wrote: ↑Sun Mar 08, 2020 4:13 pm Check the wiki. it’s an open inverter board, same brain for every inverter, just tuned differently for each motor. Open up the web interface and adjust from there.

I’m currently in the planning phase, selecting the components to get in touch with the test agency for a first talk. My question is only about “is it possible”. No SDU here and no inverter board. I can’t test it, I appreciate any proof with a Video/ Screenshot.

If torque reduction is not possible I need to go ahead with a Leaf Motor (loser power rating) and the open inverter board.

.... if you read the open inverter wiki then you’ll see that you can tune any power/torque parameters you like. Doesn’t matter what motor you use, you can try to push as much or as little power as you like...

These drop in boards are all the same basic set of software. It’s an open inverter Brain transplanted.

Bratitude wrote: ↑Sun Mar 08, 2020 8:23 pm

Gaston wrote: ↑Sun Mar 08, 2020 5:27 pm

Bratitude wrote: ↑Sun Mar 08, 2020 4:13 pm Check the wiki. it’s an open inverter board, same brain for every inverter, just tuned differently for each motor. Open up the web interface and adjust from there.

I’m currently in the planning phase, selecting the components to get in touch with the test agency for a first talk. My question is only about “is it possible”. No SDU here and no inverter board. I can’t test it, I appreciate any proof with a Video/ Screenshot.

If torque reduction is not possible I need to go ahead with a Leaf Motor (loser power rating) and the open inverter board.

.... if you read the open inverter wiki then you’ll see that you can tune any power/torque parameters you like. Doesn’t matter what motor you use, you can try to push as much or as little power as you like...

These drop in boards are all the same basic set of software. It’s an open inverter Brain transplanted.

I‘ve read/ searched the wiki and can‘t find a torque limitation value. The only lImitation which states in this direction is ocurlim to limit power torque. If I like to limit it to 87,5 kAw @ 450 V I need to set ocurlim to 194 (or a bit more to compensate losses in the motor)? Correct?

There are 4 ways to limit power:
- throtmax, limits maximum throttle, like a brick under throttle pedal
- idcmax, limits maximum DC current
- motor parameters: setting fslipmin=fslipmax=1 Hz and slipstart=100 should result in fairly low power output even from a Tesla motor
- Use a lower DC voltage - it decreases power linearly. Say 200kW @ 400V will become 50kW @ 100V with the same parameter set
ocurlim will power down the inverter completely, it is meant for hardware protection, not power limiting

Please update the wiki if it isn't clear enough.

johu wrote: ↑Mon Mar 09, 2020 12:04 pm - Use a lower DC voltage - it decreases power linearly.

Out of curiosity, how does that affect field weakening? The graphs I saw showed field weakening starts slightly above open road speed at the nominal voltage, surely if you dropped the voltage significantly it'd be running in fw mode a lot of the time and the efficiency would take a hit?