FRIT of the Smith Compensator for MIMO Time Delay Systems―The Case of Output Delays

Abstract

In this paper, we develop a controller tuning method of the Smith compensator for multi input multi output (MIMO) linear time-invariant systems with output time delays. Particularly, we apply fictitious reference iterative tuning (FRIT), which is one of the controller tuning methods with only one-shot experimental data, to such systems. Since the Smith compensator contains a model of a plant, it is expected that the model is also obtained together with control parameters by FRIT. To realize this expectation, we introduce a special structure of the Smith compensator with tunable parameters. Then, we also show that the application of FRIT to the parameterized Smith compensator yields not only a desired control parameter but also an appropriate mathematical model of a plant. To show the validity of the proposed method, we give an illustrative numerical example.