Abstract
This paper provides a closed-loop identification method based on generalized minimum variance (GMV) evaluation in case of unknown dead time. A new variance criterion to obtain process parameters and dead time simultaneously is introduced. The optimal dead time is searched for over a prescribed range of dead time. The criterion consists of input and output measurements collected from the closed-loop system with the nominal GMV control law in regulatory control. The paper proves that the optimization of the proposed criterion results in the unique optimal solution which corresponds to the true system parameters and the actual dead time. The efficiency of the proposed method is demonstrated through a numerical example.
