Structure identification and parameter estimation of benchmark processes using shape information from relay feedback test

Abstract

Most of the chemical industries use PIPID controllers Proper newlinetuning of PIPID loop needs accurate process parameters estimated from the newlineexact model structure The introduction of relay feedback test has received newlinemuch attention in the field of autotuning of PID controller Most of the relay newlinefeedback autotuners use ZeiglerNichols ZN type tuning rules to set newlinecontroller parameters which are independent of model structure and newlineassociated model parameters Such cases can lead to poor performance newlinebecause no single tuning rule can work well for all model structures The newlineshape of the relay response obtained from the relay feedback test can be used newlineas additional information in model structure identification and hence the newlineestimation of associated model parameters In this present work an attempt is made to identify the model structure of different benchmark processes using the shape information of relay response and then to estimate corresponding model parameters from the relay response data newline newline