Adaptive Tuning – Example Application

It is often possible to spot where adaptive control is needed by observing trends of control loops that show the control parameter and valve position during a time period when the process conditions change over their normal span of operation. If the control performance varies with changes in operating conditions, then adaptive tuning may be applied where the state parameter reflects the operating condition. For example, when change in performance is caused by non-linear installed valve characteristics then the implied valve position as indicated by the PID output may be used as the state parameter in the implementation of adaptive tuning. An example of this is illustrated below.

Adaptive tuning is addressed in chapter 5 of Advanced Control Foundation – Tools, Techniques and Application. The workshop for this chapter involves the implementation of adaptive control using the DeltaV control system. A YouTube video that is contained on the book’s web site shows the workshop solution .Some differences will be seen when implementing adaptive tuning on other control systems.