DESIGN OF DECOUPLED PI CONTROLLERS FOR TWO-INPUT TWO-OUTPUT NETWORKED CONTROL SYSTEMS WITH INTRINSIC AND NETWORK-INDUCED TIME DELAYS
Abstract
Proportional integral controller design for two-input two-output (TITO) networked control systems (NCSs) with intrinsic
and network-induced time delays is studied in this paper. The TITO NCS consists of two delayed sub-systems coupled in a 1-1/2-2 pairing
mode. In order to simplify the controller design, a decoupling method is first applied to obtain a decoupled system. Then, the controllers
are designed based on the transfer function matrix of the obtained decoupled system and using the boundary locus method for determining
the stability region and the well-known Mikhailov criterion for the stability test. A comparative analysis of the designed controllers and other
controllers proposed in previous literature works is thereafter carried out. To demonstrate the validity and efficacy of the proposed method
and to show that it achieves better results than other methods proposed in earlier literature works, the implementation in simulation
of Wood–Berry distillation column model (methanol–water separation), a well-known benchmark for TITO systems, is carried out.