Design of a PIα Controller for the Robust Control of the Steam Pressure in the Steam Drum of a Bagasse-Fired Boiler

Abstract

This paper proposes the design of a PI α fractional robust controller with which to regulate the steam pressure in the steam drum of a bagasse-fired boiler. The dynamic behavior of this process was identified by means of experimentation. This identification procedure yielded an equivalent third order plus time delay model, and showed wide process static gain variations. We, therefore, propose a new method with which to design fractional-order robust controllers for this kind of processes. This method is based on the exact attainment of certain nominal time specifications while using one of the parameters of the controller to maximize the gain margin. The controller attained was shown to significantly outperform the robustness achieved by using PI or PID controllers, in the sense of reducing the Integral Absolute Error (IAE) and improving the steam pressure uniformity.

Stabilizing region of fractional-order proportional integral derivative controllers for interval fractional-order plants

“…In this regard, some results on stability analysis of fractional-order systems can be found in Bonnet and Partington (2002), Busłowicz (2008), and Ghorbani and Tavakoli-Kakhki (2021a). However, the model parameters of physical systems cannot be identified precisely and may contain uncertainties because of the tolerance values of elements, nonlinear effects, or environmental conditions in practice (Feliu-Batlle et al, 2021; Yeroglu and Tan, 2011). Therefore, the parametric uncertainties are unavoidable in the real systems (Ghorbani et al, 2019).…”