Assessment of passive instability suppression means on pitch-regulated wind turbines

Riziotis, VA; Voutsinas, SG; Politis, ES; Chaviaropoulos, PK

dc.contributor.author	Riziotis, VA	en
dc.contributor.author	Voutsinas, SG	en
dc.contributor.author	Politis, ES	en
dc.contributor.author	Chaviaropoulos, PK	en
dc.date.accessioned	2014-03-01T01:27:57Z
dc.date.available	2014-03-01T01:27:57Z
dc.date.issued	2008	en
dc.identifier.issn	1095-4244	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/18651
dc.subject	Aeroelastic stability	en
dc.subject	Eigenvalue modal analysis	en
dc.subject	Rotor aerodynamics	en
dc.subject.classification	Energy & Fuels	en
dc.subject.classification	Engineering, Mechanical	en
dc.subject.other	Airfoils	en
dc.subject.other	Damping	en
dc.subject.other	Eigenvalues and eigenfunctions	en
dc.subject.other	Modal analysis	en
dc.subject.other	Aeroelastic stability	en
dc.subject.other	Eigenvalue modal analysis	en
dc.subject.other	Rotor aerodynamics	en
dc.subject.other	Wind turbines	en
dc.subject.other	Airfoils	en
dc.subject.other	Damping	en
dc.subject.other	Eigenvalues and eigenfunctions	en
dc.subject.other	Modal analysis	en
dc.subject.other	Wind turbines	en
dc.subject.other	aerodynamics	en
dc.subject.other	design	en
dc.subject.other	eigenvalue	en
dc.subject.other	model	en
dc.subject.other	optimization	en
dc.subject.other	wind turbine	en
dc.title	Assessment of passive instability suppression means on pitch-regulated wind turbines	en
heal.type	journalArticle	en
heal.identifier.primary	10.1002/we.241	en
heal.identifier.secondary	http://dx.doi.org/10.1002/we.241	en
heal.language	English	en
heal.publicationDate	2008	en
heal.abstract	The significance of three types of design modifications in view of defining passive means to extend the stability bounds of modern wind turbines is assessed in this paper. The first concerns the use of optimized airfoil shapes on a fixed blade planform while the other two concern the increase of structural flexibility by either bringing closer the flap and lead-lag mode frequencies or introducing a soft yaw connection. Such an exploration of the stability envelope aims at providing the necessary understanding of the mechanisms that control aeroelastic damping and therefore at identifying means for improving the stability behaviour of the lowest damped system modes. Stability calculations are performed in the context of linear eigenvalue analysis using a state-of-the-art stability tool. The model accounts for the full wind turbine configuration and the eigenvalue problem is formulated with reference to the non-rotating (ground-fixed) frame of reference through the multi-blade transformation of all the rotating degrees of freedom. Results are presented in reference to a commercial multi-MW, pitch-regulated, variable-speed wind turbine. They indicate that the soft yaw concept offers more significant margins of improvement compared with the flap-lag coincidence, while aerodynamic optimization could be a basis for improvement. Copyright © 2007 John Wiley & Sons, Ltd.	en
heal.publisher	JOHN WILEY & SONS LTD	en
heal.journalName	Wind Energy	en
dc.identifier.doi	10.1002/we.241	en
dc.identifier.isi	ISI:000255144400003	en
dc.identifier.volume	11	en
dc.identifier.issue	2	en
dc.identifier.spage	171	en
dc.identifier.epage	192	en