Introduction to the Discrete LSDP Controller and the Performance by Exploiting the Gap Metric Theory

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This paper describes the introduction to the discrete LSDP (Loop Shaping Design Procedure) controller in order to develop a robust controller which guarantees the stability for the family of uncertain systems. To determine the validity domain of the discrete LSDP (DLSDP) we propose to use the gap metric theory for studying robustness properties as a function of the stability margin provided by the DLSDP controller with respect to parameter uncertainties. The latter are modeled by using the left normalized coprime factors (NCFs) representation. The effectiveness of the DLSDP controller is validated on a second-order electrical linear system.
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Discrete Loop Shaping; DLSDP Controller; Robust Control; Gap Metric

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