A comparison of different scheduling techniques for H-infinity controllers

Abstract

Several approaches to designing schedule H-infinity control systems are compared. These include a controller switching approach and also parameter scheduling of an observer representation of the controller. They are illustrated by application to a Generic VSTOL Aircraft Model (GVAM) supplied by The Royal Aerospace Establishment (RAE) at Bedford. The switched design has been tested on the simulator at RAE Bedford. The linear H-infinity designs make use of a loop-shaping followed by robust stabilisation to additive perturbations of a normalised coprime factorisation of the shaped plant. The different scheduling approaches are compared with respect to achieved robust stability levels, performance and complexity of implementation.

Keywords

H-infinity robust control VSTOL scheduling switching

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