Haven’t posted an update in a while.
Dug into the compressor characteristic / turbine power calculations a bit and put together this. Excuse the MSPaint skills ....
View attachment 17199
KW value from compressor characteristic table corrected with PID based on boost error and exhaust target flow then goes into exhaust flow, temp, and pressure models to get a WG/Turbine distribution factor. This distribution factor is turned into WGDC with the WG Position model and then the spring in the actuator is compensated for with the WGFEDER table. This “base WGDC” value is then blended with the feed forward tables. That value is summed with the altitude correction, pressure dynamics correction, and offset by gear. This value goes into the adaption function, a damping function and is then added to the output of the I controller. Note, this is a second I controller, the first adds kW to the turbine power value and uses exhaust gas mass flow. The I controller most are familiar with is the second one which adds or subtracts WGDC and uses mass airflow and boost error as axes. There are various limiters, most of which are raised in the stock M2 BIN. For the most part I have been successful leaving most of the PID set as in the M2 bin and modifying/rescaling just the compressor characteristic table with the P, I, and D tables zero’d to get boost close to target. Then turning PID back on. I found one of what I thought was my best revisions made about 8psi less with PID turned off. Obviously the compressor table wasn’t right and PID was just adding a ton. Would really be nice to be able to log the individual PID terms like N54.
A couple more notes. WGDC Base log channel appears to be the output of the compressor characteristic table in kW. I don’t believe it is WGDC.
I’m not sure what WGDC after PID is.
In my bin I’ve rescaled the WG position model to a linear 1-100% and zero’d the WGFEDER table (how an EWG car is). I know this is incorrect as the PWG model is not linear because the WGDC does not result in a linear change in WG position but I personally have found it easier to tune this way.
There’s a lot more I’m leaving out I’m sure but just wanted to spark up the PID tuning discussion again.
Spool is great, boost follows target no problem, but it still spikes a few PSI post shift on DCT and AT cars. The WG tables for post shift are all only active on MT.
@LamboLover you mentioned your custom boost control strategy on GTR resolves a similar issue. Any insight?