Control of high-order processes: repeated-pole plus dead-time models' identification

This paper aims to present two approaches for repeated-pole plus dead-time (RPPDT) models identification procedures for highorder processes based. First approach is based on using two or three points over the process reaction curve −an open-loop test− whereas the second approach is based on the use of the process relay control oscillating signals −a closed-loop test. Equations are provided for both model parameters identification as well as order estimation. Comparison tests confirm that the RPPDT models provide a better representation of the high-order process dynamics than its simple, usually employed, first-order approximation. These models are suitable for process representation in dynamic simulations and control system design studies.