Observer-based control of systems with slope-restricted nonlinearities

An observer design is presented which makes use of bounds on the slope of system nonlinearities. Necessary and sufficient conditions are derived for the feasibility of the design. A class of state feedback control laws are characterized which, when implemented with the observer states, ensure global asymptotic stability. One such certainty-equivalence design is illustrated on an active magnetic bearing example.

[1]  P. Kokotovic,et al.  Feasibility conditions for circle criterion designs , 2001 .

[2]  P. Kokotovic,et al.  Nonlinear observers: a circle criterion design , 1999, Proceedings of the 38th IEEE Conference on Decision and Control (Cat. No.99CH36304).

[3]  Alberto Isidori,et al.  Nonlinear Control Systems II , 1999 .

[4]  E. Panteley,et al.  On global uniform asymptotic stability of nonlinear time-varying systems in cascade , 1998 .

[5]  A. Isidori.  Nonlinear Control Systems , 1985 .

[6]  Carl R. Knospe,et al.  Gain-scheduled control of a magnetic bearing with low bias flux , 1997, Proceedings of the 36th IEEE Conference on Decision and Control.

[7]  Panagiotis Tsiotras,et al.  Low-bias control of AMBs subject to saturation constraints , 2000, Proceedings of the 2000. IEEE International Conference on Control Applications. Conference Proceedings (Cat. No.00CH37162).

[8]  Petar V. Kokotovic,et al.  Nonlinear observers: a circle criterion design and robustness analysis , 2001, Autom..