the handbrake was unfortunately not the problem, the inverter was defective. probably got too hot and therefore 1 or 2 phases failed. With a new inverter it drives smoothly again

Hahaha, you are right

Is it possible to change the topic name to jerky car problems, it makes more sense then rotordir problem

Thanks, I re-run the updater and it works again

I also found the jerking problem!!!
The handbrake of one wheel got stuck. After fixing the brake it all works

Thanks Johannes for your responses and help.

I tried 3 different firmware versions: v5.35_r_sine, v5.32_r_sine and v5.27_r_sine, same problem.

During the last firmware update by accident the 12V to the SDU was disconnected, now I can't connect to the board again.....

Is there a way to connect to the board again with CAN and upload a new ...

Is it possible with my hardware to downgrade to 5.13.R-sine? I have more experience with this firmware version.

This problem only happens once in the 5 times at starting up the car. The other 4 times there is no problem at all and the car drives smoothly

It is not possible to drive, the car only bouncing. When you press the throttle the bouncung gets louder.
When you push the car a bit forward and it starts rolling it is possible to drive bud it drives jerky.

Here is a plot of fstat, idc and potnom

Here are two plots with potnom, pot and idc.

One drive unit

Sorry Johannes, you are right about the version, it is v5.34.R-sine

My maximum voltage is 84cells x 4,2V = 353V

I have attached the 2 screenshots of the spot values, one is from a godd working SDU and one from a jerky SDU.

When the SDU starts jerking the rotordir and seldir have opposite value, this behaviour is very constant.

Here are the params

(5.35.R on inverter, v2.2 of web interface)

I have some trouble with my SDU rotordir.
The SDU works fine, only sometimes when I start the drive unit the spotvalues 'seldir' and 'rotordir' are opposite. In this case the car is not driving at all, when I press the trottle the car is very jerky. This ...