Feedforward component in PID tuning (DBW)

[VSCM]

Hi all. While I was tuning a pid (drive-by-wire) on my m800 I noticed the section "feedforward". I know that feedforward consists of sending a percentage of the input directly to the output with no control action.
How does this affect the behaviour of the system? How can I choose the correct value while tuning the PID without damaging the ETB? Using the feedforward component could reduce the lag between TPD and TPS?
Thank you for your support.

[Blu302]

The feed forward is used to counter against the return spring.

The safest option is to get Motec to tune it if they don't have the settings already.

The lag between the TPD and TPS is from the PID being slow. When Motec tuned my BMW throttle for my M800, it reacts faster than you can move with your foot. I was shown this using hand input with a twitch, which it followed perfectly.

[Vlad]

Yep...ask MoTeC for that info...it’s quite risky to do it yourself

[Blu302]

If the "system" doesn't track fast enough, it will go into fault and shut down the DBW