Tesla SDU - Unable to get any regen at all  [SOLVED]

Topics concerning the Tesla front and rear drive unit drop-in board
Post Reply
User avatar
cloudy
Posts: 202
Joined: Wed Oct 02, 2019 12:15 am
Location: UK
Been thanked: 1 time

Tesla SDU - Unable to get any regen at all

Post by cloudy »

Pulling my hair out, so posting here as a last resort. Otherwise fine Tesla SDU running on openinverter - however I cannot no matter what I try and do, get any regen at all (potnom never drops below zero)

Params attached, but I've tried many variations and trying to have pot2 both set to zero and 4095. My expectation is there should be some regen ramped in when off throttle. I'm really hoping I've missed something incredibly stupid. Can anyone suggest? Is it possible I need a pot2 value above the value of ~23 I have now - even when setting pot2 max to zero?

Running 5.14 - params attached

Thankyou!
Attachments
params (1).json
(1.44 KiB) Downloaded 60 times
User avatar
johu
Site Admin
Posts: 5682
Joined: Thu Nov 08, 2018 10:52 pm
Location: Kassel/Germany
Has thanked: 153 times
Been thanked: 960 times
Contact:

Re: Tesla SDU - Unable to get any regen at all

Post by johu »

Looks ok. Is udc measuring correctly?
Support R/D and forum on Patreon: https://patreon.com/openinverter - Subscribe on odysee: https://odysee.com/@openinverter:9
User avatar
cloudy
Posts: 202
Joined: Wed Oct 02, 2019 12:15 am
Location: UK
Been thanked: 1 time

Re: Tesla SDU - Unable to get any regen at all

Post by cloudy »

Yes, reading about 400V - I've even reapplied damian's default params and tried to add some regen to no avail. Perhaps I have a corrupt config memory? Is it worth using the default revert button?
remy_martian
Posts: 47
Joined: Fri Mar 22, 2019 7:44 pm

Re: Tesla SDU - Unable to get any regen at all

Post by remy_martian »

Is there a flag or other boolean / signal that says the battery is fully charged?
Friends don't let software friends do hardware design
User avatar
johu
Site Admin
Posts: 5682
Joined: Thu Nov 08, 2018 10:52 pm
Location: Kassel/Germany
Has thanked: 153 times
Been thanked: 960 times
Contact:

Re: Tesla SDU - Unable to get any regen at all

Post by johu »

If the parameter memory is corrupt it will load (useless) defaults anyway as a CRC is stored along with the parameters.

I'm assuming your throttle is also calibrated correctly?
Support R/D and forum on Patreon: https://patreon.com/openinverter - Subscribe on odysee: https://odysee.com/@openinverter:9
User avatar
cloudy
Posts: 202
Joined: Wed Oct 02, 2019 12:15 am
Location: UK
Been thanked: 1 time

Re: Tesla SDU - Unable to get any regen at all

Post by cloudy »

Yes, throttle within range. I've also added a brake digital input and wired up pot2. Even with pot2 calibrated and set high - potnom never drops below zero. Pulling the digital brake input high shows activated, and inhibits throttle, but again no regen and no negative potnom at rest or whilst motor spinning. Error memory showing no errors.

What parameters out of range could cause regen to be inhibited? udcmax, idcmin, throtmin, bmslimlow? Possible to have a sign wrong? idcmin should be entered as negative value right?
User avatar
johu
Site Admin
Posts: 5682
Joined: Thu Nov 08, 2018 10:52 pm
Location: Kassel/Germany
Has thanked: 153 times
Been thanked: 960 times
Contact:

Re: Tesla SDU - Unable to get any regen at all

Post by johu »

Code: Select all

   throtSpnt = GetUserThrottleCommand();
   bool determineDirection = GetCruiseCreepCommand(finalSpnt, throtSpnt);
   finalSpnt = Throttle::RampThrottle(finalSpnt);

   if (hwRev != HW_TESLA)
      Throttle::BmsLimitCommand(finalSpnt, Param::GetBool(Param::din_bms));

   Throttle::UdcLimitCommand(finalSpnt, Param::GetFloat(Param::udc));
   Throttle::IdcLimitCommand(finalSpnt, Param::GetFloat(Param::idc));
   Throttle::FrequencyLimitCommand(finalSpnt, Param::GetFloat(Param::fstat));

   if (Throttle::TemperatureDerate(Param::GetFloat(Param::tmphs), Param::GetFloat(Param::tmphsmax), finalSpnt))
   {
      DigIo::err_out.Set();
      ErrorMessage::Post(ERR_TMPHSMAX);
   }

   if (Throttle::TemperatureDerate(Param::GetFloat(Param::tmpm), Param::GetFloat(Param::tmpmmax), finalSpnt))
   {
      DigIo::err_out.Set();
      ErrorMessage::Post(ERR_TMPMMAX);
   }
Does that help? It's not the BMS input it is masked out on Tesla hardware. It's none of the temp deraters because they would limit acceleration as well and trigger an error message. idc/udc you have configured correctly. Maybe try setting idlemode to off?
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: 5682
Joined: Thu Nov 08, 2018 10:52 pm
Location: Kassel/Germany
Has thanked: 153 times
Been thanked: 960 times
Contact:

Re: Tesla SDU - Unable to get any regen at all  [SOLVED]

Post by johu »

Oh yeah, just checked again. You have speedkp=0 . That means the idle speed controller will override any negative throttle. Not greatest usability I admit. Set idlemode off and speedkp=0.25
Support R/D and forum on Patreon: https://patreon.com/openinverter - Subscribe on odysee: https://odysee.com/@openinverter:9
User avatar
cloudy
Posts: 202
Joined: Wed Oct 02, 2019 12:15 am
Location: UK
Been thanked: 1 time

Re: Tesla SDU - Unable to get any regen at all

Post by cloudy »

That fixed it! Many thanks 8-) 8-) 8-)
Post Reply