research @ wolfgang-reinelt.de |
control and analysis of systems with hard constraints |
---|

This area of research is dedicated to the design of robust linear feedback controllers for MIMO and LTI plants, subject to hard constraints on the plant input (control variable). Most applications in control engineering involve hard constraints on the plant input (eg a flow rate in a valve); unfortunately, there are only few design procedures which deal with such constraints. In practical usage, this has led to ad-hoc methods (or, in the worst case, wait-and-see-what-happens methods), which have little theoretical justification.

The approach used is a saturation

To solve the problem of the constrained plant input as mentioned above,
the amplitude of the external (here: reference) signal has to be bounded,
too. Earlier works of Dourdoumas and Reichel showed, that the average load
of the control variable is better (and moreover some kind of optimisation
is possible), when the first derivative of the reference signal is bounded
(in amplitude) as well. A central problem within this approach is the determination
of the maximum output of a LTI-system (under these prerequisites), which
is solved via Reichel's "Balkenverfahren", that constructs the optimal (i.e.
the maximum output amplitude achieving input signal). An improvement of this
algorithm is possible via nonlinear optimisation. In many cases, however,
the optimal solution can be determined by linear programming techniques.
This problem is discussed in the Master's thesis and following works:

- W. Reinelt.
**Entwurf optimaler Regler bei amplitudenbeschränkten Systemgrössen.**Master's Thesis, Univ. Paderborn/Dept. of Mathematics, December 1993 - W. Reinelt.
**Maximum Output Amplitude of Linear Systems for certain Input Constraints.**In*Proc. of the 39th IEEE Conference on Decision and Control*. pp 1075-1080. Sydney, Australia, December 2000. A preliminary version is available as Technical Report LiTH-ISY-R-2292 - W. Reinelt.
**Worst case output of uncertain systems.**Technical Report LiTH-ISY-R-2347 October 2000.

- W. Reinelt.
**Entwurf von robusten Regelkreisen unter der Berücksichtigung von Stellgrössenbeschränkungen.**In*10. Steirisches Seminar über Regelungstechnik und Prozessautomatisierung*. Leibnitz/Austria, September 1997, pp54-70 - W. Reinelt.
**Robuste Mehrgrössenregelung von Systemen mit harten Stellgrössenbeschränkungen.**

In*32. Regelungstechnisches Kolloquium*. Boppard/Germany, February 1998, pp21-22 - W. Reinelt.
**Robust Control of Systems subject to Hard Constraints.**(abstract , light version , publisher info ) Dissertation, Paderborn University, April 1998. Published by Shaker Verlag, Aachen, Germany, 1998, ISBN 3 8265 3816 1 - W. Reinelt.
**H**In_{ }Loop Shaping for Systems with Hard Bounds.*Proc. of the Int. Symposium on Quantitative Feedback Theory and Robust Frequency Domain Methods*. Durban/South Africa, 26-27 August 1999 (an extended version is available in the Technical Report LiTH-ISY-R-2166 , Dept of EE, Linköping University, Linköping, Sweden, June 1999) - W. Reinelt.
**Loop Shaping of multivariable Systems with hard constraints on the control signal.***Electrical Engineering*Volume 83 Issue 4 (2001) pp.169-177. A preliminary version is available as Technical Report LiTH-ISY-R-2320 - W. Reinelt.
**Control of Multivariable Systems with hard constraints.**In*Proc. of the European Control Conference*. Porto, Portugal, Sept 2001. A preliminary version is available as Technical Report LiTH-ISY-R-2348

- W. Reinelt.
**Robust control of a two-mass-spring system subject to its input constraints.**In*Proc. of the American Control Conference*. Chicago, IL, USA. June 2000. A preliminary version is available as Technical Report LiTH-ISY-R-2201 , August 1999. - W. Reinelt and M. Canale.
**Robust control of SISO systems with hard input constraints.**In*Proc. of the European Control Conference*. Porto, Portugal, Sept 2001. A preliminary version is available as Technical Report LiTH-ISY-R-2349 , May 2001.

- W. Reinelt.
**Entwurf optimaler Regler bei amplitudenbeschränkten Systemgrössen.**Master's Thesis, Univ. Paderborn/Dept. of Mathematics, December 1993 - W. Reinelt.
**Design of optimal control systems with bounded control signals.**In*Proc. of the European Control Conference*. Porto, Portugal, Sept 2001. A preliminary version is available as Technical Report LiTH-ISY-R-2350 , May 2001.

- W. Reinelt.
**Aspects of analysis and design of saturation-avoiding controllers.**In E&CE Seminar. Dept of Electrical and Computer Engineering, University of Newcastle, NSW 2308, Australia, 15 Jan 2001. - W. Reinelt.
**Design of saturation-avoiding controllers: a double Youla approach to deal with plant uncertainty.**Seminar at Dept of Automatic Control, Lund Institute of Technology/Sweden, Nov 13, 2000 - W. Reinelt.
**Robust Control of Systems with Hard Constraints.**Seminar at Dept of Automatic Control, Lund Institute of Technology/Sweden, April 27, 1999 - W. Reinelt.
**Multivariable Control of Uncertain Systems with Bounded Inputs.**Seminar at Division of Automatic Control, University of Linköping/Sweden, November 12, 1998 - W. Reinelt.
**The Two-Mass-Spring Benchmark Problem: An Unstructured Uncertainty Approach for the Constrained Control Problem.**Seminar at Centre for Systems and Control, University of Glasgow/Scotland, October 9, 1998 - W. Reinelt.
**Entwurf von robusten Mehrgrössenregelkreisen unter der Berücksichtigung von harten Stellgrössenbeschränkungen.**Elektrotechnisches Kolloquium, Univ. of Paderborn/Germany, November 18, 1997

Last updated Mon Sep 2 19:25:43 2002 by Wolfgang Reinelt . Legal Disclaimer