EXPONENTIAL TRACKING WITH DISTURBANCE ATTENUATION (ETDA) BY OUTPUT FEEDBACK

This paper considers an exponential zero-offset tracking problem for a class of nonlinear systems with model uncertainty and unmeasured disturbances. A nonlinear H∞-controller with exponential stability is firstly developed based on a technique in Lu and Doyle (IEEE Trans. Automatic Control 39 (1994) 2517) and then applied to establish a controller which guarantees exponential tracking with zero-offset of step reference signals. Further, a robust control scheme is designed to handle model uncertainties. Finally, the application of the new control method is demonstrated through simulations of controlling a pH neutralisation process in the presence of disturbances and model uncertainties.

[1]  P. Moylan,et al.  Connections between finite-gain and asymptotic stability , 1980 .

[2]  J. Willems.  Dissipative dynamical systems part I: General theory , 1972 .

[3]  P. Khargonekar,et al.  State-space solutions to standard H/sub 2/ and H/sub infinity / control problems , 1989 .

[4]  J. Doyle,et al.  𝓗∞ Control of Nonlinear Systems via Output Feedback: Controller Parameterization , 1994, IEEE Trans. Autom. Control..

[5]  P. Khargonekar,et al.  State-space solutions to standard H2 and H∞ control problems , 1988, 1988 American Control Conference.

[6]  M. A. Henson,et al.  Critique of exact linearization strategies for process control , 1991 .

[7]  J. Helton,et al.  H/sup infinity / control for nonlinear plants: connections with differential games , 1989, Proceedings of the 28th IEEE Conference on Decision and Control,.

[8]  Dale E. Seborg,et al.  Modelling and Self-Tuning Control of a Multivariable pH Neutralization Process Part I: Modelling and Multiloop Control , 1989, 1989 American Control Conference.

[9]  P. Moylan,et al.  The stability of nonlinear dissipative systems , 1976 .

[10]  G. Johnson,et al.  Synthesis of control systems with stability constraints via the direct method of Lyapunov , 1964 .

[11]  Weibiao Zhou,et al.  Exponential tracking with disturbance attenuation (EDTA) and its numerical solution , 1998 .

[12]  J. Helton,et al.  H" CONTROL FOR NONLINEAR PLANTS: CONNECTIONS WITH DIFFERENTIAL GAMES , 1989 .

[13]  Austin Blaquière,et al.  Nonlinear System Analysis , 1966 .

[14]  A. Schaft.  L/sub 2/-gain analysis of nonlinear systems and nonlinear state-feedback H/sub infinity / control , 1992 .

[15]  J. Cloutier,et al.  Control designs for the nonlinear benchmark problem via the state-dependent Riccati equation method , 1998 .