PidCC increase rate limits not working 800xA 5.1 fp4
I'm having problems with the new PidCC included in ControlStandardLib 1.5-11 released in 800xA 5.1 feature pack 4.
I want to block the output of the PID from increasing and I have set the following in the interaction parameters:
InteractionPar.Aux.LimitOutput := True;
InteractionPar.Aux.OutIncLim := 0.0;
Usually this is enough to block output increase but not in the new PidCC. Output is still increasing if I change the process value.
I have also triede enabling output ramping in manual mode, setting output range and disabling PDpart at antiwindup.
Any ideas or experiences here?
Voted best answer
In my experience, the "Limit Output" option only enables the Min/Max Limit for the Output, there is no "Change Rate Limitation" built into PidCC. The OutIncLim only applies for Output changes during Mode change with no "I" Part where there would be a step in the Ouput otherwise. I believe the behavior was like this in earlier Versions as well but i could be wrong...
You could use a "VelocityLimiterCC" after the PidCC to have a Limit applied on the Output, but this will affect the Controller behaviour (windup etc.).