Robust controller design for uncertain systems with variable time delay

• DOI: 10.1016/s0967-0661(01)00040-5
• Publication Date: 2002-07-25T21:22:19Z
• Authors: M. Garcı́a-Sanz; J.C. Guillén; J.J. Ibarrola
• Keywords: Robustness; Smith predictor

Abstract A Smith predictor controller (SPC) is designed for an uncertain pasteurisation process exhibiting variable time delay. As the SPC may be very sensitive to model-plant mismatch, especial attention must be paid to ensure robustness of the design when the model of the plant is not precisely known. This paper introduces two criteria for such cases. The first criterion is based on bandwidth considerations and the second one introduces some guidelines to improve the design by using the quantitative feedback theory technique. An experimental verification of the proposed methodology on the pasteurisation plant is also presented.