Robust controller design using H/sub /spl infin// loop-shaping and the method of inequalities

A new approach to robust controller design is proposed. By using plant-weighting functions as the design parameters, the approach combines the method of inequalities with robust stabilization of normalized coprime factor descriptions of the weighted plant to design explicitly for closed-loop performance and stability robustness. A procedure for the design of robust two degree-of-freedom controllers is presented and is illustrated on a high-purity distillation column example.<
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