Modified Smith predictor scheme for periodic disturbance reduction in linear delay systems

Yi De Chen, Pi Cheng Tung, Chyun Chau Fuh

Research output: Contribution to journalArticlepeer-review

50 Scopus citations


This paper presents a disturbance reduction scheme for linear systems with time delays. The linear systems in the study are assumed to be nominally stable, minimum phase, and relative degree one systems. The proposed scheme is a combination of Astrom's modified Smith predictor with a disturbance reduction controller and a grey predictor. Unlike conventional disturbance rejection methods, the scheme proposed in this study does not require the estimation of disturbance frequencies. The grey prediction method is used to approximate the inverse of the time delay and to enhance the robustness of the disturbance reduction scheme against errors in the estimated delay time. The simulation results demonstrate the successful performance of the proposed disturbance reduction method for controlling a linear system with time delays, subjected to both step and periodic disturbances.

Original languageEnglish
Pages (from-to)799-804
Number of pages6
JournalJournal of Process Control
Issue number10
StatePublished - Dec 2007


  • Delay time
  • Disturbance reduction
  • Grey predictor
  • Modified Smith predictor


Dive into the research topics of 'Modified Smith predictor scheme for periodic disturbance reduction in linear delay systems'. Together they form a unique fingerprint.

Cite this