Section: New Results

PID tuning for controlling delayed dynamics

Participants : Jie Chen [City University of Hong Kong] , Jianqi Chen [City University of Hong Kong] , Andong Liu [City University of Hong Kong] , Dan Ma [Northeastern University, China] , Silviu Niculescu.

Nowadays, the PID controller is the most used in controlling industrial processes. In [21] such a controller is further explored in the control of delayed dynamics. An explicit lower bound on the delay margin of second-order unstable delay systems achievable by PID control is established, which provides a priori a guaranteed range of delay values over which a second-order delay plant can be stabilized by a PID, and more generally, a finite-dimensional LTI controller. This is done by deriving lower bounds on the delay margin achievable by PD controllers, whereas this margin constitutes a lower bound on that achievable by PID controllers. Analysis shows that in most cases our results can be significantly less conservative than the lower bounds obtained elsewhere using more sophisticated, general LTI controllers.