Improved design of the weighting matrices for the S/KS/T mixed sensitivity problem-application to a multivariable thermodynamic system

This paper describes an improved design procedure for the weighting matrices of the S/KS/T mixed sensitivity problem. Using low-order models, as usual in industrial processes, and based on recent works, the new design will allow to significantly reduce the time response overshoots, without degrading the speed of these responses. Weighting matrices are designed in such a way that they depend only on a few parameters, which can be easily adjusted by means of the proposed methodology. Experimental results in the simultaneous control of two temperatures of a pilot plant (which constitutes a typical example of industrial process) are included in order to validate the proposed methodology.