Korean Chemical Engineering Research

The Korean Institute of Chemical Engineers (한국화학공학회)
권호 표지
DOI QR코드

DOI QR Code

Liquid Level System Realizing Van de Vusse Reactor Dynamics and its Control Experiments

Van de Vusse 반응기 동특성을 구현하는 액위시스템 및 제어 실험

  • Lee, Jietae (Department of Chemical Engineering, Kyungpook National University)
  • 이지태 (경북대학교 화학공학과)
  • Received : 2019.09.18
  • Accepted : 2020.03.06
  • Published : 2020.05.01
Download PDF
⟨ Previous Next ⟩

Abstract

Van de Vusse reactors show the maximum points in input-output steady state maps and dramatic changes in their dynamic characteristics around those maximum points. According to their operating regions, there appear sign changes in steady state gains and nonlinear characteristics such as non-minimum phase dynamics which cause difficulties in applying controllers. Many nonlinear controllers that are available and newly designed are applied to these Van de Vusse reactor processes and their performances are tested. Reactor examples with real reactions have been reported. However, due to difficulties in constructing and operating chemical reactor systems, they are not adequate to be used for real applications of control experiments and hence most of results are based on simulations studies. Here, we propose a liquid level system that realizes most of the steady state and dynamic characteristics of Van de Vusse reactor, and two nonlinear control methods that can be used as base methods to compare nonlinear controllers newly designed. Liquid level experimental system and two nonlinear control methods are very simple and can be used to test performances of nonlinear controllers in practice.

Van de Vusse 반응기는 정상상태 입출력 관계에서 최대값을 그리고 이 최대값을 기준으로 동특성의 형태가 크게 바뀌는 특성을 보인다. 운전영역에 따라 정상상태 이득의 부호가 바뀌고, non-minimum phase 동특성 등의 제어를 매우 어렵게 하는 특성들이 나타난다. 매우 많은 비선형제어 방법들과 새로이 고안되고 있는 방법들이 이 Van de Vusse 반응기 공정에 적용되어 그 성능 검증이 이루어지고 있다. 이 반응기의 실제 예가 보고되어 있으나, 화학반응 특성상 제어기 실험에 일상적으로 사용되기에는 어려움이 많아 대부분 모사연구에 그치고 있다. 여기서는 이 Van de Vusse 반응기의 특성을 모두 구현하는 액위시스템을 제작하고, 새로이 고안되는 비선형 제어기의 성능을 밝히는 기준이 될 수 있는 간단한 두 제어 방법의 실험 결과를 제안하고자 한다. 액위시스템 실험장치와 제안된 제어 방법들은 매우 간단하며, 비선형 제어기의 성능과 현장 적용 가능성을 검증하는데 유용하게 사용될 수 있을 것이다.

Keywords

References

  1. Van de Vusse, J. G.. "Plug-flow Type Reactor Versus Tank Reactor," Chem. Eng. Sci., 19, 994-997(1964). https://doi.org/10.1016/0009-2509(64)85109-5
  2. Engeli, S. and Klatt, K. U., "Nonlinear Control of a Non-Minimum-Phase CSTR," American Control Conference, San Francisco, June 1993.
  3. Koppel, L. B., "Input Multiplicities in Nonlinear, Multivariable Control Systems," AIChE Journal, 28(6), 935(1982). https://doi.org/10.1002/aic.690280608
  4. Dash, S. K. and Koppel, L. B., "Sudden Destabilisation of Controlled Chemical Processes," Chem. Eng. Comm., 84, 129-157(1989). https://doi.org/10.1080/00986448908940339
  5. Sistu, P. B. and Bequette, B. W., "Model Predictive Control of Processes with Input Multiplicities," Chem. Eng. Sci., 50, 921-936(1995). https://doi.org/10.1016/0009-2509(94)00477-9
  6. Lee, J. and Edgar, T. F., "Nonlinear Parallel Compensators for Controlling Processes with Input Multiplicities," Korean J. Chem. Eng., 32, 1-7(2015). https://doi.org/10.1007/s11814-014-0286-x
  7. Krstic, M. and Wang, H. H., "Stability of Extremum Seeking Feedback for General Dynamic Systems," Automatica, 36, 595-601 (2000). https://doi.org/10.1016/S0005-1098(99)00183-1
  8. Guay, M., "A Time-varying Extremum-seeking Control Approach for Discrete-time Systems," J. Process Control, 24, 98-112(2014). https://doi.org/10.1016/j.jprocont.2013.11.014
  9. Lee, J. and Lee, K. S., "Extremum Seeking Control Using a Partial Sum of Input-Output Product," Korean J. Chem. Eng., 33, 3079-3084(2016). https://doi.org/10.1007/s11814-016-0223-2
  10. Wright, R. A. and Kravaris, C., "Nonminimum Phase Compensation for Nonlinear Processes," AIChE Journal, 38(1), 26-40(1992). https://doi.org/10.1002/aic.690380104
  11. Kuhlmann, A. and Bogle, D., "Study on Nonminimum Phase Behaviour and Optimal Operation," Comp. Chem. Engng, 21, 397-402(1997). https://doi.org/10.1016/S0098-1354(97)00081-1
  12. Wu, W., "Stable Inverse Control for Nonminimum-phase Nonlinear Processes," J. Process Control, 9, 171-183(1999). https://doi.org/10.1016/S0959-1524(98)00030-4
  13. Doyle III, F. J., Ogunnaike, B. A. and Pearson, R. K., "Nonlinear Model-based Control Using Second-order Volterra Models," Automatica, 31, 697-714(1995). https://doi.org/10.1016/0005-1098(94)00150-H
  14. Klatt, K. U. and Engell, S., "Gain-scheduling Trajectory Control of a Continuous Stirred Tank Reactor," Comp. Chem. Engng, 22, 491-502(1998). https://doi.org/10.1016/S0098-1354(97)00261-5
  15. Wu, W., "Adaptive Nonlinear Control of Nonminimum-phase Processes," Chem. Eng. Sci., 54, 3815-3829(1999). https://doi.org/10.1016/S0009-2509(99)00030-5
  16. Perez, H., Ogunnaike, B. and Devasia, S., "Output Tracking Between Operating Points for Nonlinear Processes: Van de Vusse Example," IEEE Transactions on Control Systems Technology, 10, 611-617(2002). https://doi.org/10.1109/TCST.2002.1014680
  17. Ma, K., Valdes-Gonzalez, H., David, I. and Bogle, L., "Process Design in SISO Systems with Input Multiplicity Using Bifurcation Analysis and Optimization," J. Process Control, 20, 241-247(2010). https://doi.org/10.1016/j.jprocont.2009.12.005
  18. Tsai, S. H., "Robust $H_{\infty}$ Control for Van de Vusse reactor via T-S Fuzzy Bilinear Scheme," Expert Systems with Applications, 38, 4935-4944(2011). https://doi.org/10.1016/j.eswa.2010.09.158
  19. Kuntanapreeda, S. and Marusak, P. M., "Nonlinear Extended Output Feedback Control for CSTRs with Van de Vusse Reaction," Comp. Chem. Engng, 41, 10-23(2012). https://doi.org/10.1016/j.compchemeng.2012.02.010
  20. Seborg, D. E., Mellichamp, D. A., Edgar, T. F. and Doyle III, F. J., Process Dynamics and Control, 3rd ed. New York, Wiley, 2010.