blockTuningMonitor

Monitor the tuning process

Information

This block detects when a PID tuning period should start and end. Specifically, the tuning period is triggered to begin when either tOn or tOff becomes greater than 0. The tuning period is triggered to end when either tOn or tOff changes after the tuning period starts, as illustrated below:

image

Note:

This block monitors the values of tOn and tOff to detect the start and end of the tuning period. Rapid changes in these values can cause unreliable event triggering during variable time-step integration. To enhance robustness, a small tolerance eps is introduced. Increasing eps can help ensure correct event detection if any events are missed.

References

J. Berner (2017). "Automatic Controller Tuning using Relay-based Model Identification." Department of Automatic Control, Lund University.

Parameters

TypeNameDefaultDescription
Modelica.Units.SI.Timeeps1E-5A small tolerance applied to determine whether a variable is greater than zero

Connectors

TypeNameDefaultDescription
Buildings.Controls.OBC.CDL.Interfaces.RealInputtOnLength for the on period
Buildings.Controls.OBC.CDL.Interfaces.RealInputtOffLength for the off period
Buildings.Controls.OBC.CDL.Interfaces.BooleanOutputtriStaA boolean signal, true if the tuning starts
Buildings.Controls.OBC.CDL.Interfaces.BooleanOutputtriEndA boolean signal, true if the tuning completes

Revisions

  • March 31, 2026, by Michael Wetter:
    Corrected unit propagation error that causes Dymola 2026x to not show certain units.
    See #2100.
  • September 20, 2023, by Sen Huang:
    First implementation.