The identification of nonlinear models for process control using tailored “plant-friendly” input sequences

Abstract This paper considers certain practical aspects of the identification of nonlinear empirical models for chemical process dynamics. The primary focus is the identification of second-order Volterra models using input sequences that offer the following three advantages: (1) they are “plant friendly;” (2) they simplify the required computations; (3) they can emphasize certain model parameters over others. To provide a quantitative basis for discussing the first of these advantages, this paper defines a friendliness index f that relates to the number of changes that occur in the sequence. For convenience, this paper also considers an additional nonlinear model structure: the Volterra–Laguerre model. To illustrate the practical utility of the input sequences considered here, second-order Volterra and Volterra–Laguerre models are developed that approximate the dynamics of a first-principles model of methyl methacrylate polymerization.

[1]  Robert D. Nowak,et al.  Random and pseudorandom inputs for Volterra filter identification , 1994, IEEE Trans. Signal Process..

[2]  Jay H. Lee,et al.  Input sequence design for parametric identification of nonlinear systems , 1997, Proceedings of the 1997 American Control Conference (Cat. No.97CH36041).

[3]  M. Schetzen The Volterra and Wiener Theories of Nonlinear Systems , 1980 .

[4]  S. A. Billings,et al.  Experimental design and identifiability for non-linear systems , 1987 .

[5]  C. Kravaris,et al.  Feedforward/feedback control of multivariable nonlinear processes , 1990 .

[6]  Ronald K. Pearson,et al.  Identification of structurally constrained second-order Volterra models , 1996, IEEE Trans. Signal Process..

[7]  G. Dumont,et al.  An optimum time scale for discrete Laguerre network , 1993, IEEE Trans. Autom. Control..

[8]  Babatunde A. Ogunnaike,et al.  Process Dynamics, Modeling, and Control , 1994 .

[9]  Michael Nikolaou,et al.  NONLINEARITY QUANTIFICATION AND ITS APPLICATION TO NONLINEAR SYSTEM IDENTIFICATION , 1998 .

[10]  E. Zafiriou,et al.  Nonlinear system identification for control using Volterra-Laguerre expansion , 1995, Proceedings of 1995 American Control Conference - ACC'95.

[11]  Leon O. Chua,et al.  Fading memory and the problem of approximating nonlinear operators with volterra series , 1985 .

[12]  Daniel E. Rivera,et al.  Restricted Complexity Approximation of Nonlinear Processes Using a Control-Relevant Approach , 1996 .

[13]  Jay H. Lee Modeling and Identification for NonlinearModel Predictive Control: Requirements,Current Status and Future Research Needs , 2000 .

[14]  Manfred Morari,et al.  PLS/neural networks , 1992 .

[15]  W. Harmon Ray,et al.  On the Mathematical Modeling of Polymerization Reactors , 1972 .

[16]  J. Kurth,et al.  Identification of Nonlinear Systems with Reduced Volterra-series , 1994 .

[17]  Lennart Ljung,et al.  System Identification: Theory for the User , 1987 .

[18]  Ronald K. Pearson,et al.  Nonlinear model-based control using second-order Volterra models , 1995, Autom..

[19]  W. Rugh Nonlinear System Theory: The Volterra / Wiener Approach , 1981 .

[20]  Guy A. Dumont,et al.  Non-linear adaptive control via Laguerre expansion of Volterra kernels , 1993 .

[21]  A. Isidori Nonlinear Control Systems: An Introduction , 1986 .

[22]  John P. Congalidis,et al.  Feedforward and feedback control of a solution copolymerization reactor , 1989 .

[23]  Francis J. Doyle,et al.  Identification and Control Using Volterra Models , 2001 .

[24]  E. Zafiriou,et al.  Nonlinear dynamical system identification using reduced Volterra models with generalised orthonormal basis functions , 1997, Proceedings of the 1997 American Control Conference (Cat. No.97CH36041).

[25]  Thomas J. McAvoy,et al.  Nonlinear PLS Modeling Using Neural Networks , 1992 .