On-line retuning of PID controllers with fixed threshold samplers

Oscar Miguel-Escrig; Julio-Ariel Romero-Pérez; José Sánchez-Moreno; Sebastián Dormido

doi:10.1016/j.isatra.2023.04.003

On-line retuning of PID controllers with fixed threshold samplers

ISA Trans. 2023 Aug:139:253-262. doi: 10.1016/j.isatra.2023.04.003. Epub 2023 Apr 11.

Authors

Oscar Miguel-Escrig¹, Julio-Ariel Romero-Pérez², José Sánchez-Moreno³, Sebastián Dormido⁴

Affiliations

¹ Departamento de Ingeniería de Sistemas Industriales y Diseño, UJI, Castelló, Spain. Electronic address: omiguel@uji.es.
² Departamento de Ingeniería de Sistemas Industriales y Diseño, UJI, Castelló, Spain. Electronic address: romeroj@uji.es.
³ Departamento de Informática y Automática, UNED, Madrid, Spain. Electronic address: jsanchez@dia.uned.es.
⁴ Departamento de Informática y Automática, UNED, Madrid, Spain. Electronic address: sdormido@dia.uned.es.

PMID: 37059671
DOI: 10.1016/j.isatra.2023.04.003

Abstract

The appearance of limit cycle oscillations in control systems with fixed threshold based samplers degrades the performance of the control loop, accelerates the wear out of actuators, and introduces an unnecessary communication overhead in distributed control systems. In this paper, the role of the input signals to the control loop is taken into account when analyzing the existence of limit cycles induced by fixed threshold samplers. With this analysis, a methodology to re-tune PID controllers while running to avoid limit cycle oscillations generated by ramp-like excitation signals is presented. Implementation guidelines and several examples to illustrate the usefulness of the method are provided.

Keywords: DIDF; EBC; PID control; Retuning; Robustness.