Simple analytical min-max model matching approach to robust proportional-integrative-derivative tuning with smooth set-point response

This communication addresses the set-point robust proportional-integrative- derivative (PID) tuning for stable first order plus time delay systems from a general min-max model matching formulation. As opposed to some recent optimization-based numerical procedures, the derivation is carried out analytically, and it is based on a Smith-type inverse response configuration. Within the considered context, several choices result in a standard PID. This work investigates the simplest one, leading to a PID controller solely depending on a single design parameter. This contrasts with other analytical approaches resulting in more involved tuning. Attending to common performance/robustness indicators, the free parameter is finally fixed to provide an automatic tuning solely dependent on the model information. Toward this transition, dimensional analysis proves fruitful and allows us to establish that the proposed tuning rule is very robust for lead-dominant plants in the presence of parametric uncertainty. Lastly, simulation examples show that the suggested compensator yields very good results. © 2010 American Chemical Society.