On-line PI controller tuning for integrator/dead time processes

This paper presents two new methods for tuning PI controllers for integrato r plus dead time models (IPDT). The simple IPDT model was found to be a use ful approximation of more complex models such as first-order plus dead time models with large time constants. The use of IPDT models can, in these cas es, simplify and also accelerate the auto-tuning step especially in MIMO pr ocesses. The advantages of the proposed methods over the known tuning metho ds are demonstrated through simulation examples.