Multi-objective control for stochastic model reference systems based on LMI approach and sliding mode control concept

Abstract

In this article, a multi-objective control u(t) is designed for stochastic model reference systems to achieve the following three objectives simultaneously: the pole placement constraint, H _∞-norm constraint and individual error state variance constraint. Using the invariance property of sliding mode control, the reference model input and the plant error term will disappear on the sliding mode of the error system. By combining the upper bound covariance control theory, pole placement skill and H _∞-norm control theory, a controller, in which the control feedback gain matrix is synthesised utilising linear matrix inequality (LMI) approach, is derived to achieve the above multiple objectives. Furthermore, a practical example for the problem of ship yaw-motion systems is adopted to illustrate the proposed method.

Keywords:

• stochastic model reference systems
• sliding mode control
• individual error state variance constraint
• ship yaw-motion systems
• linear matrix inequality approach

Acknowledgements

This study was supported by the National Science Council of Taiwan, ROC, under the grant NSC 93-2218-E-270-003.