Simplified tuning of IMC based modified smith predictor for UFOPDT processes
-
Somak Karan
and
Chanchal Dey
Abstract
A simplified tuning guideline for internal model control (IMC) based modified Smith predictor technique is reported here for unstable lag dominated first-order processes with dead time (UFOPDT). Pole location in right half section of s-plane signifies the unstable behaviour of UFOPDT processes. Mostly, chemical processes like isothermal chemical reactor, bioreactor, dimerization reactor, fluid catalytic cracker etc. are found to be lag dominated and unstable along with considerable time delay. Smith predictor technique based control methodology is considered to be a well-accepted approach for such cases. However, conventional Smith predictor technique is not capable enough for controlling UFOPDT processes. Whereas modified Smith predictor is found to be quite competent in such cases as its design involves more than one controller. Modified Smith predictor structure is capable to provide desirable closed loop response during set point tracking along with the load recovery phases. To mitigate the tuning complexity of multiple controllers involved in modified Smith predictor designing, suggested IMC structure employs single tuning parameter λ i.e. closed loop time constant for all three controllers concerned. Noticeable performance enhancement is reported by the proposed scheme as no overshoot is observed during set point tracking. Moreover, smooth and efficient load rejection behaviour is also obtained. Supremacy of the proposed tuning is established through closed loop performance comparison with others’ reported modified Smith predictor based tuning relations for chemical reactor and bioreactor in terms of performance indices as well as stability margins.
Correction notes
Correction added after online publication on June 11, 2020: In a previous version of this article, one of the authors Somak Karan name was published mistakenly as Karan Somak. Also the running header on every page, was mistakenly published as “S. Karan and D. Chanchal: Mod. Smith pre. of UFOPDT processes”.
Author contribution: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.
Research funding: None declared.
Employment or leadership: None declared.
Honorarium: None declared.
Conflict of interest statement: The authors declare no conflicts of interest regarding this article.
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Articles in the same Issue
- Frontmatter
- Research Articles
- Simulation of CO2 removal from pressurized natural gas stream contains high CO2 concentration by absorption process using membrane contactors
- Simplified tuning of IMC based modified smith predictor for UFOPDT processes
- Numerical investigation of heat and mass transfer during hydrogen sorption in a mixture of AB2 – AB5 metal hydride for hydrogen storage
- Numerical study of serpentine flow field designs effect on proton exchange membrane fuel cell (PEMFC) performance
- Statistical Modelling and Optimisation of the Biosorption of Cd(II) and Pb(II) onto Dead Biomass of Pseudomonas Aeruginosa
- Numerical Modeling of Phenol Adsorption on Granular Activated Carbon Fixed Bed: Comparison of Two Numerical Methods to Solve the Advection-dispersion Equation
Articles in the same Issue
- Frontmatter
- Research Articles
- Simulation of CO2 removal from pressurized natural gas stream contains high CO2 concentration by absorption process using membrane contactors
- Simplified tuning of IMC based modified smith predictor for UFOPDT processes
- Numerical investigation of heat and mass transfer during hydrogen sorption in a mixture of AB2 – AB5 metal hydride for hydrogen storage
- Numerical study of serpentine flow field designs effect on proton exchange membrane fuel cell (PEMFC) performance
- Statistical Modelling and Optimisation of the Biosorption of Cd(II) and Pb(II) onto Dead Biomass of Pseudomonas Aeruginosa
- Numerical Modeling of Phenol Adsorption on Granular Activated Carbon Fixed Bed: Comparison of Two Numerical Methods to Solve the Advection-dispersion Equation
