PID - changing Gain parameter

BryanG2001

Hello to you too.

When the seagulls follow the trawler, it is because they think sardines will be thrown into the sea.

Or to put it another way, philosophy is great but it don't feed the chickens.

Regards

The PID Compact controller has additional parameters. With these parameters, the overshoot can be reduced (step setpoint change). The disadvantage is, at each PID parameters change, the I-Part has to be manipulated for bumpless switching. The I-Part is shown in the writable variable

sPid_Cmpt.r_Ctrl_IOutv

The calculation of an appropriate I-Part is not that easy. But the controller can do this automatically. You have to write the parameters into the structure “sBackUp” in static DB. You activate the new parameters using the “sPid_Cmpt.b_LoadBackUp” in static. The controller calculates a new I-Part for bumpless switching automatically.

EFE700 is right, by setting DB.LoadBackUp to TRUE for one cycle it will adapt to the new settings without bumping the output.

Works fine during Mode=3 on PID_Compact V2.2

Yes I know it's been a while since the last post, but this tip is very helpful and the only one I could find that address this problem with changing gain etc on the fly.

I'll guess this is a feature of autotuning when you want to go back to the previous settings.