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Editor-in-Chief

Nikiforov
Vladimir O.
D.Sc., Prof.
Partners
doi: 10.17586/2226-1494-2018-18-1-32-42
SMITH SCHEME APPLICATION IN THE SERVO SYSTEM WITH DELAY IN THE MAIN FEEDBACK
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Article in Russian
For citation: Bystrov S.V., Vunder N.A., Pavlov A.S., Sinetova M.M., Ushakov A.V. Smith scheme application in the servo system with delay in the main feedback. Scientific and Technical Journal of Information Technologies, Mechanics and Optics, 2018, vol. 18, no. 1, pp. 32–42 (in Russian). doi: 10.17586/2226-1494-2018-18-1-32-42
Abstract
For citation: Bystrov S.V., Vunder N.A., Pavlov A.S., Sinetova M.M., Ushakov A.V. Smith scheme application in the servo system with delay in the main feedback. Scientific and Technical Journal of Information Technologies, Mechanics and Optics, 2018, vol. 18, no. 1, pp. 32–42 (in Russian). doi: 10.17586/2226-1494-2018-18-1-32-42
Abstract
Subject of Research.The subject of the study is the system situation that arises when a continuous plant is included in the system, the main feedback in which contains the link of pure delay. It is shown that for this system situation it is advisable to design a control device for continuous plant in the form of a consecutive compensator. It is found that if the consecutive compensator is included in the structure of the system according to the Smith scheme, then the transfer function of the input-output ratio of such system will not contain the transfer function of the pure delay link neither in the numerator, nor in the denominator, therefore the delay in the main feedback does not affect the system behavior. This property of the system with a consecutive compensator included in the Smith scheme enables the developer to use an algorithm of its synthesis created for plant control systems without delay. Method. The algorithmic basis is based on the use of the Mason method of non-tangential circuits for the transformation of signal structures and the procedure for the synthesis of a consecutive compensator, as a device for controlling continuous plants without delay. The method is based on the properties of typical polynomial models. Main Results. The developer of continuous systems with main feedback with delay obtains a simple algorithm for the synthesis of a consecutive compensator included in the Smith scheme, which completely excludes the effect of the pure delay link on the system behavior. Practical Relevance. The obtained results are of practical value for cases when a plant is included in the system with main feedback containing a pure delay. This is especially important for real technological processes. Practical application of the obtained results is illustrated by computer experiment.
Keywords: continuous plant, servo system, consecutive compensator, pure delay link in the main feedback, Smith scheme, Mason rule, consecutive compensator synthesis algorithm
Acknowledgements. This work was supported by the Government of the Russian Federation, Grant 074-U01; the Ministry of Education and Science of the Russian Federation, Project 14.Z50.31.0031; the Russian Federation President Grant No.14.Y31.16.9281-НШ.
References
Acknowledgements. This work was supported by the Government of the Russian Federation, Grant 074-U01; the Ministry of Education and Science of the Russian Federation, Project 14.Z50.31.0031; the Russian Federation President Grant No.14.Y31.16.9281-НШ.
References
1. KimD.P. Algebraic method of the synthesis control system for a plant with a pure (transport) delay. Mechatronics, Automation, Control, 2012, no. 10, pp. 2–7. (In Russian)
2. Gaiduk A.R. Theory and Methods of Analytical Synthesis of Automatic Control Systems (Polynomial Approach). Moscow, Fizmatlit Publ., 2012, 360 p. (In Russian)
3. Bystrov S.V., Vunder N.A., Sinetova M.M., Ushakov A.V. Analytical design of consecutive compensator for control systems with delay based on modification of typical polynomial models. SPIIRAS Proceedings, 2017, vol. 52, no. 3, pp. 115–136. (In Russian)
4. Smith O.J.M. Close control of loops with dead time. Chemical Engineering Progress, 1957, vol. 53, pp. 217–235.
5. Smith O.J.M. A controller to overcome dead time. ISA J, 1959, vol. 6, no. 2, pp. 28–32.
6. Majhi S., Atherton D.P. New Smith predictor and controller for unstable and integrating processes with time delay. Proc. 37th IEEE Conference on Decision and Control. Tampa, USA, 1998, vol. 2, pp. 1341–1345.
7. Palmor Z.J. Time-delay compensation - Smith predictor and its modifications. In The Control Handbook. Ed. W.S. Levine. Boca Raton, USA, CRSC Press, 1996, pp. 224–237.
8. Astrom K.J., Hang C.C., Lim B.C. A new Smith predictor for controlling a process with an integrator and long dead-time. IEEE Transactions on Automatic Control, 1994, vol. 39, no. 2, pp. 343–345. doi: 10.1109/9.272329
9. Matausek M.R., Ribic A.I. Control of stable, integrating and unstable processes by the Modified Smith Predictor. Journal of Process Control, 2012, vol. 22, no. 1, pp. 338–343. doi: 10.1016/j.jprocont.2011.08.006
10. Karafyllis I., Krstic M. Delay-robustness of linear predictor feedback without restriction on delay rate. Automatica, 2013, vol. 49, no. 6, pp. 1761–1767. doi: 10.1016/j.automatica.2013.02.019
11. Vunder N.A., Ushakov A.V. Sensitivity analysis of systems with a cascade compensator embedded in a Smith predictor to dead-time variation. Optoelectronics, Instrumentation and Data Processing, 2016, vol. 52, no. 3, pp. 274–279. doi: 10.3103/S8756699016030092
12. Vunder N.A., Ushakov A.V. Sensitivity analysis of systems with a cascade compensator embedded in a Smith predictor to dead-time variation. Optoelectronics, Instrumentation and Data Processing, 2016, vol. 52, no. 3, pp. 274–279.doi: 10.3103/S8756699016030092
13. Bystrov S.V., Vunder N.A., Ushakov A.V. Solution of signal uncertainty problem at analytical design of consecutive compensator in piezo actuator control. Scientific and Technical Journal of Information Technologies, Mechanics and Optics, 2016, vol. 16, no. 3, pp. 451–459. (In Russian) doi: 10.17586/2226-1494-2016-16-3-451-459
14. Mason S.J. Feedback theory - further properties of signal flow graphs. Proceedings of the IRE, 1956, vol. 44, no. 7,
pp. 920–926. doi: 10.1109/JRPROC.1956.275147
pp. 920–926. doi: 10.1109/JRPROC.1956.275147
15. Zadeh L.А., Desoer C.А. Linear System Theory: The State Space Approach. NY,Dover Publications,2008, 656 p.