Observer‐based synthesis of linear parameter‐varying mixed sensitivity controllers

• Published in: International journal of robust and nonlinear control Vol. 30; no. 13; pp. 5021 - 5039
• Main Authors: Theis, Julian, Pfifer, Harald
• Format: Journal Article
• Language: English
• Published: Bognor Regis Wiley Subscription Services, Inc 10.09.2020
• Subjects: Active control; Aeroelasticity; control synthesis algorithm; coprime factorization; Feedback; Feedback control; Flutter; flutter suppression; linear parameter‐varying control; observer; Output feedback; Parameter sensitivity; State feedback; Synthesis; Unmanned aircraft
• ISSN: 1049-8923; 1099-1239; 1099-1239
• DOI: 10.1002/rnc.5038

Summary This article presents a computationally efficient way of synthesizing linear parameter‐varying (LPV) controllers. It reviews the possibility of a separate observer and state feedback synthesis with guaranteed performance and shows that a standard mixed sensitivity problem can be solved in this way. The resultant output feedback controller consists of an LPV observer, augmented with dynamic filters to incorporate integral control and roll‐off properties, and an LPV state feedback gain. It is thus highly structured, which is beneficial for implementation. Moreover, it does not depend on scheduling parameter rates regardless of whether parameter‐dependent Lyapunov matrices are used during synthesis. A representative control design for active flutter suppression on an aeroelastic unmanned aircraft demonstrates the benefits of the proposed method in comparison with state‐of‐the‐art LPV output feedback synthesis.