Improved LQG Method for Active Gust Load Alleviation
Publication: Journal of Aerospace Engineering
Volume 30, Issue 4
Abstract
Against a background of various techniques for gust load alleviation (GLA), this paper aims at proposing an improved linear quadratic Gaussian (LQG) method, which is robust to variations of flight parameters, structural parameters, and modeling errors and suitable for application in structure/control design optimization. This new technique differs from the traditional LQG methodology by the introduction of properly constructed fictitious high-frequency noise. Furthermore, to accurately measure the stability margins of the multi-input multi-output (MIMO) controllers, a variable-structure analysis method is proposed. The parameters of the Dryden continuous gust model are adjusted according to the structural natural frequencies to meet the design requirements, and model reduction combined with input signal scaling is applied to reduce the controller order. Using a general transport aircraft (GTA) model, the robust performance and robust stability of the improved LQG method are compared with those of modern robust controllers, including the controller and the -synthesis controller. The numerical results demonstrate the successful application of this new technique.
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Acknowledgments
This research work was fully supported by the Industry-University-Research Project of China Aviation Industry Corporation (Grant No. Cxy2010xG18). The authors are grateful for the financial support.
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Published In
Journal of Aerospace Engineering
Volume 30 • Issue 4 • July 2017
Copyright
©2017 American Society of Civil Engineers.
History
Received: May 18, 2016
Accepted: Oct 5, 2016
Published online: Jan 30, 2017
Discussion open until: Jun 30, 2017
Published in print: Jul 1, 2017
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