Stabilizing dynamic control design for systems with time-varying delay in control loop

Behrouz Ebrahimi, Reza Tafreshi, Javad Mohammadpour, Matthew Franchek, Karolos Grigoriadis

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

Synthesis of nth-order dynamic systems with time-varying delay in the control loop is considered in this paper. First-order Padé approximation is sought to solve the infinite-dimensional problem of the pure delay. Although the approximation describes the problem in a finite-dimensional state space, it poses internal dynamics instability inherited from the resulted non-minimum phase system. The unstable internal dynamics restricts the system closed-loop bandwidth and leads to an imperfect tracking performance. To circumvent this problem, the overall system dynamics is explored in terms of unstable internal dynamics and input/output pairs. The system internal dynamics is used to design a parameter-varying dynamic compensator which stabilizes the internal dynamics based on a desired tracking error profile. The presented dynamic compensator is used to develop a dynamic controller whose parameter-varying gains are explicitly determined in a systematic and straightforward manner. The proposed approach is used to design a controller for a spark ignition lean-burn engine with large time-varying delay in the control loop. The results are demonstrated against a baseline PI controller combined with a parameter-varying Smith predictor to compensate for the time-varying delay.

Original languageEnglish
Title of host publication2014 American Control Conference, ACC 2014
PublisherInstitute of Electrical and Electronics Engineers Inc.
Pages5558-5563
Number of pages6
ISBN (Print)9781479932726
DOIs
Publication statusPublished - 1 Jan 2014
Event2014 American Control Conference, ACC 2014 - Portland, OR, United States
Duration: 4 Jun 20146 Jun 2014

Publication series

NameProceedings of the American Control Conference
ISSN (Print)0743-1619

Other

Other2014 American Control Conference, ACC 2014
CountryUnited States
CityPortland, OR
Period4/6/146/6/14

    Fingerprint

Keywords

  • Automotive
  • Delay systems
  • Time-varying systems

ASJC Scopus subject areas

  • Electrical and Electronic Engineering

Cite this

Ebrahimi, B., Tafreshi, R., Mohammadpour, J., Franchek, M., & Grigoriadis, K. (2014). Stabilizing dynamic control design for systems with time-varying delay in control loop. In 2014 American Control Conference, ACC 2014 (pp. 5558-5563). [6859299] (Proceedings of the American Control Conference). Institute of Electrical and Electronics Engineers Inc.. https://doi.org/10.1109/ACC.2014.6859299