Details

Autor(en) / Beteiligte

• K, Ghousiya Begum
• A, Seshagiri Rao
• T.K., Radhakrishnan

Titel

Performance assessment of control loops involving unstable systems for set point tracking and disturbance rejection

Ist Teil von

• Journal of the Taiwan Institute of Chemical Engineers, 2018-04, Vol.85, p.1-17

Ort / Verlag

Elsevier B.V

Erscheinungsjahr

2018

Link zum Volltext

Quelle

Elsevier ScienceDirect Journals Complete

Beschreibungen/Notizen

• •A direct synthesis and IAE based performance index was developed to evaluate the controller's performance.•Lower bound of IAE was determined for step and ramp type of changes.•Unstable first and second order time delay processes are considered for evaluation.•Eight simulation examples were presented to evaluate the proposed performance benchmark. In this article, a performance assessment method that measures the performances of set point tracking as well as disturbance rejection characteristics of PID controllers designed for unstable processes is proposed. The lower bounds of integral absolute errors (IAEo) are derived from the desired closed loop transfer function subjected to set point changes which may be of step or ramp types. The performance index is developed by considering Direct Synthesis (DS) method for PID controller design. Based on the theoretical bound IAE0, a dimensionless index is elucidated as the ratio between IAE0 and the actual IAE obtained from closed loop response under step set point changes and load variable changes. Considering this IAE based index as the performance measure of PI/PID control loops, the effectiveness of the controller is evaluated and tested on different types of unstable first order or second order plus time delay processes. Simulation studies for both set-point changes and disturbance rejection on various numerical examples are performed to prove the validity of the suggested performance benchmark. [Display omitted]