Exploiting Actuator Limits with Feedforward Control based on Inverse Models

Manuel Gräber
TLK-Thermo GmbH, Braunschweig, Germany

Ladda ner artikelhttp://dx.doi.org/10.3384/ecp14096637

Ingår i: Proceedings of the 10th International Modelica Conference; March 10-12; 2014; Lund; Sweden

Linköping Electronic Conference Proceedings 96:67, s. 637-645

Visa mer +

Publicerad: 2014-03-10

ISBN: 978-91-7519-380-9

ISSN: 1650-3686 (tryckt), 1650-3740 (online)


Feedforward control based on inverse dynamic plant models (linear or nonlinear) is a suitable method to enhance set-point tracking performance of control systems. In reality actuators always have limits; but limiting functions can not be inverted. A common approach to handle this issue is to invert the unlimited plant model and detune the feedforward filter in order to stay always in between the actuator limits. This approach causes a loss in performance for rapid set-point changes; because the actuator range is not entirely used. In this article a rather simple but powerful method is presented; which overcomes this performance issue for many types of plant models. Actuator limits are fully exploited; and the obtained trajectories are close to optimal ones. Simulation and measurement results demonstrate the usability of the proposed feedforward structure.


Set-point tracking; model inversion; actuator saturation; nonlinear control; model-based control; anti-windup


[1] Karl Johan Åström and Lars Rundqwist. Integrator windup and how to avoid it. In Proc. of the American Control Conference, 1989.

[2] N. Bajcinca and T. Bünte. A novel control structure for dynamic inversion and tracking tasks. In Proc. of the 16th IFAC World Congress,, Prague, 2005.

[3] T. Blochwitz, M. Otter, M. Arnold, C. Bausch, C. Clauß, H. Elmqvist, A. Junghanns, J. Mauss,M. Monteiro, T. Neidhold, D. Neumerkel, H. Olsson, J.-V. Peetz, and S. Wolf. The Functional Mockup Interface for Tool independent Exchange of Simulation Models. In Proc of the 8th International Modelica Conference, Dresden, 2011.

[4] H. G. Bock and K. J. Plitt. A Multiple Shooting algorithm for direct solution of optimal control problems. In Proc. of the 9th IFAC World Congress Budapest, pages 243–247. Pergamon Press, 1984.

[5] G.M. Clayton, S. Tien, a.J. Fleming, S.O.R. Moheimani, and S. Devasia. Inverse-feedforward of charge-controlled piezopositioners. Mechatronics, 18(5-6):273–281, June 2008.

[6] Moritz Diehl. Real-Time Optimization for Large Scale Nonlinear Processes. Phd thesis, Universität Heidelberg, 2001.

[7] R. Hanus, M. Kinnaert, and J.-L. Henrotte. Conditioning technique, a general anti-windup and bumpless transfer method. Automatica, 23(6):729–739, 1987.

[8] Stephen W John, Gursel Alici, and Christopher D Cook. Inversion-based feedforward control of polypyrrole trilayer bender actuators. IEEE/ASME Transactions on Mechatronics, 15(1):149–156, 2010.

[9] D B Leineweber, I Bauer, A A S Schäfer, H G Bock, and J P Schlöder. An Efficient Multiple Shooting Based Reduced SQP Strategy for Large-Scale Dynamic Process Optimization (Parts I and II). Computers and Chemical Engineering, 27:157–174, 2003.

[10] Chung Seng Ling, Michael D Brown, Paul FWeston, and Clive Roberts. Gain Tuned Internal Model Control for Handling Saturation in Actuators. In Proc. of the American Control Conference, Boston, 2004.

[11] Gertjan Looye, Michael Thümmel, Matthias Kurze, Martin Otter, and Johann Bals. Nonlinear Inverse Models for Control. In Proc. of the 4th International Modelica Conference, Hamburg, 2005.

[12] Riccardo Marino. High-gain feedback in nonlinear control systems. International Journal of Control, 42(6):1369–1385, 1985.

Citeringar i Crossref