An Enhanced Smith Predictor Based Control System Using Feedback-feedforward Structure for Time-delay Processes

M. Mohammadzaheri, R. Tafreshi

Abstract


This paper presents enhanced Smith predictor based control systems (SPBCSs) for processes with a time-varying or fixed time delay. This work focuses on improving the arrangement and asynchrony of SPBCS components rather than the design of the predictor and the feedback controller, which have been well discussed in the literature. The proposed control system advances SPBCS through implementation of two design recommendations: (i) replacing the classical feedback controller by a feedback-feedforward control system, and (ii) synchronizing the reference signal and the predicted output. As a result, common shortcomings of SPBCSs or control systems based on Pade approximation, i.e. the trade-off between performance and steady-state error, and instability associated with non-minimum-phase systems do not exist in the proposed SPBCS. The superior performance of the proposed control system is demonstrated with two examples: temperature control of an infrared dryer (a system with fixed time-delay) and air-fuel ratio of a lean-burn spark-ignition engine (a system with time-varying delay and lag). The proposed control system is shown to clearly outperform the conventional SPBCS and Internal Model Control (IMC) PID based on Pade approximation for aforementioned examples and performs satisfactorily in the presence of noises, actuator saturations, and severe model inaccuracies.


Keywords


Smith predictor; Time delay system; Dryer; Engine.

Full Text:

PDF

References


Aryan P, Mohammadzaheri M, Chen L, Ghanbari M, Mirsepahi A (2010), GA-IMC based PID control design for an infrared dryer, Chemeca Adelaide, South Australia.

Astrom KJ, Hang CC, Lim B (1994), A new smith predictor for controlling a process with an integrator and long dead-time. IEEE transactions on Automatic Control 39(2): 343-345.

Bequette BW (2008), Process control, modeling, design and simulation. New Delhi, Prentice Hall of India.

Bresch-Pietri D, Krstic M (2009), Adaptive trajectory tracking despite unknown input delay and plant parameters. Automatica 45(9): 2074-2081.

Chuanzhu S, Xiangyou W, Chao G, Lifang P (2005), Development of far infrared dryer of 5HY model for vegetables [J]. Transactions of The Chinese Society of Agricultural Engineering 5: 020.

De Luca A (2000), Feedforward/feedback laws for the control of flexible robots, IEEE International Conference on Robotics and Automation San Francisco, USA.

DePoar A (1985), A modified smith predictor and controller for unstable processes with time delay. International Journal of Control 41(4): 1025-1036.

Ebrahimi B, Tafreshi R, Franchek M, Grigoriadis KM Mohammadpour J (2014a), A dynamic feedback control strategy for control loops with time-varying delay. International Journal of Control 87(5): 887-897.

Ebrahimi B, Tafreshi R, Masudi H, Franchek M, Mohammadpour J, Grigoriadis K (2012), A parameter-varying filtered PID strategy for air-fuel ratio control of spark ignition engines. Control Engineering Practice 20(8): 805-815.

Ebrahimi BR, Tafreshi J, Mohammadpour M, Franchek K, Grigoriadis, Masudi H (2014b), Second-order sliding mode strategy for air--fuel ratio control of lean-burn SI engines. IEEE Transactions on Control System Technology 22(4): 1374-1384.

Fiengo G, Grizzle J, Cook JA, Karnik AY (2005), Dual-UEGO active catalyst control for emissions reduction: Design and experimental validation. IEEE Transactions on Control Systems Technology 13(5): 722-736.

Ghodsi M, Hosseinzadeh N, Özer A, Dizaj HR, Hojjat Y, Varzeghani NG, Sheykholeslami MR, Talebian S, Ghodsi MH, Al-Yahmadi A (2017), Development of gasoline direct injector using giant magnetostrictive materials. IEEE Transactions on Industry Applications 53(1): 521-529.

Kwak HJ, Sung SW, Lee IB, Park JY (1999), A modified smith predictor with a new structure for unstable processes. Industrial and Engineering Chemistry Research 38(2): 405-411.

Li X, deSouza CE (1997), Delay-dependent robust stability and stabilization of uncertain linear delay systems: A linear matrix inequality approach. IEEE Transactions on Automatic Control 42(8): 1144-1148.

Lin JH, Chen P, Wang (2017), AFR control of a gasoline engine using triple-step method, 29th Chinese Control And Decision Conference, Chongqing, China.

Liu PL (2014), Further results on delay-range-dependent stability with additive time-varying delay systems. ISA Transactions 53(2): 258-266.

Mataušek MR, Ribić AI (2012), Control of stable, integrating and unstable processes by the modified smith predictor. Journal of Process Control 22(1): 338-343.

Mirsepahi A, Mehdizadeh A, Chen L, O’Neill B, Mohammadzaheri M (2017), Comparison of inverse modelling and optimization-based methods in the heat flux estimation problem of an irradiative dryer/furnace. Journal of Computational Science 19: 77-85.

Mohammadzaheri M, Chen L, Behnia-Willison F, Aryan P (2009), A design approach for feedback-feedforward control systems. IEEE International Conference on Control and Automation, Christchurch, New Zealand.

Mohammadzaheri M, Chen L, Mirsepahi A, Ghanbari M, Tafreshi R (2015), Neuro‐predictive control of an infrared dryer with a feedforward‐feedback approach. Asian Journal of Control 17(5): 1972-1977.

Mohammadzaheri M, Tafreshi R, Ebrahimi B, Grigoriadis (2015), A predictive strategy to control time-varying delay systems: Lean-Burn Engines, ASME Dynamic Systems and Control Conference, Columbus, Ohio, USA.

Pace S, Zhu GG (2014), Transient air-to-fuel ratio control of an spark ignited engine using linear quadratic tracking. Journal of Dynamic Systems, Measurement, and Control 136(2): 021008.

Reed TR, Meyer WJ, Van EM, Hermann D (2000), Infrared dryer system for printing presses, Google Patents.

Roknul AS, Zhang M, Mujumdar AS, Wang Y (2014), A comparative study of four drying methods on drying time and quality characteristics of stem lettuce slices (Lactuca sativa L.). Drying Technology 32(6): 657-666.

Sanz RP, García QC, Zhong, Albertos (2017), Predictor-based control of a class of time-delay systems and its application to quadrotors. IEEE Transactions on Industrial Electronics 64(1): 459-469.

Sharma G, Verma R, Pathare P (2005), Mathematical modeling of infrared radiation thin layer drying of onion slices. Journal of Food Engineering, 71(3): 282-286.

Smith OJ (1957), Closer control of loops with dead time. Chemical Engineering Progress 53(5): 217-219.

Woodward (2014), Fuel controls for engines. from http:// www.woodward.com / Applications-Engines.aspx.

Wu M, He Y, She JH (2010), Stability analysis and robust control of time-delay systems, Springer.

Zhong QC (2006), Robust control of time-delay systems, Springer.

Zope R, Mohammadpour J, Grigoriadis K, Franchek M, Tafreshi R, Masoudi H (2011), Identification of air-fuel ratio dynamics in SI engines using linear parameter varying techniques control and applications, Vancouver, Canada.




DOI: http://dx.doi.org/10.24200/tjer.vol14iss2pp156-165

Refbacks

  • There are currently no refbacks.




Copyright (c) 2018 M. Mohammadzaheri and R. Tafreshi

Creative Commons License
This work is licensed under a Creative Commons Attribution-NoDerivatives 4.0 International License.

TJER 2017-CC BY-ND

This journal and its content is licensed under a Attribution-NoDerivatives 4.0 International.

Flag Counter