TY  - CHAP
A1  - Altay, Okyay
A1  - Taddei, Francesca
A1  - Butenweg, Christoph
A1  - Klinkel, Sven
T1  - Vibration mitigation of wind turbine towers with tuned mass dampers
T2  - Wind turbine control and monitoring. (Advances in industrial control)
N2  - Because of its minor environmental impact, electricity generation using wind power is getting remarkable. The further growth of the wind industry depends on technological solutions to the challenges in production and construction of the turbines. Wind turbine tower vibrations, which limit power generation efficiency and cause fatigue problems with high maintenance costs, count as one of the main structural difficulties in the wind energy sector. To mitigate tower vibrations auxiliary measures are necessary. The effectiveness of tuned mass damper is verified by means of a numeric study on a 5 MW onshore reference wind turbine. Hereby, also seismic-induced vibrations and soil–structure interaction are considered. Acquired results show that tuned mass damper can effectively reduce resonant tower vibrations and improve the fatigue life of wind turbines. This chapter is also concerned with tuned liquid column damper and a semiactive application of it. Due to its geometric versatility and low prime costs, tuned liquid column dampers are a good alternative to other damping measures, in particular for slender structures like wind turbines.
Y1  - 2014
SN  - 978-3-319-08412-1 (Print) ; 978-3-319-08413-8 (E-Book)
U6  - https://doi.org/10.1007/978-3-319-08413-8_12
SP  - 337
EP  - 373
PB  - Springer
CY  - Cham ; Heidelberg ; New York ; Dordrecht ; London
ER  - 
TY  - CHAP
A1  - Altay, Okyay
A1  - Butenweg, Christoph
A1  - Klinkel, Sven
A1  - Taddei, Francesca
T1  - Vibration mitigation of wind turbine towers by tuned liquid column dampers
T2  - Proceedings of the 9th European Conference on Structural Dynamics, EURODYN 2014 Porto, Portugal, 30 June - 2 July 2014 / A. Cunha, E. Caetano, .... (eds.)
Y1  - 2014
SN  - 978-972-752-165-4
SP  - 1531
EP  - 1538
CY  - Porto
ER  - 
TY  - CHAP
A1  - Altay, Okyay
A1  - Butenweg, Christoph
A1  - Klinkel, Sven
T1  - Vibration mitigation of wind turbine towers by a new semiactive Tuned Liquid Column Damper
T2  - 6. Word Congress on Structural Control and Monitoring, 15 - 17 July, 2014 Barcelona,Spain
Y1  - 2014
ER  - 
TY  - JOUR
A1  - Alebouyeh Samami, Behzad
A1  - Pieper, Martin
A1  - Breitbach, Gerd
A1  - Hodapp, Josef
T1  - Heat production in the windings of the stators of electric machines under stationary condition
JF  - Heat and mass transfer
N2  - In electric machines due to high currents and resistive losses (joule heating) heat is produced. To avoid damages by overheating the design of effective cooling systems is required. Therefore the knowledge of heat sources and heat transfer processes is necessary. The purpose of this paper is to illustrate a good and effective calculation method for the temperature analysis based on homogenization techniques. These methods have been applied for the stator windings in a slot of an electric machine consisting of copper wires and resin. The key quantity here is an effective thermal conductivity, which characterizes the heterogeneous wire resin-arrangement inside the stator slot. To illustrate the applicability of the method, the analysis of a simplified, homogenized model is compared with the detailed analysis of temperature behavior inside a slot of an electric machine according to the heat generation. We considered here only the stationary situation. The achieved numerical results are accurate and show that the applied homogenization technique works in practice. Finally the results of simulations for the two cases, the original model of the slot and the homogenized model chosen for the slot (unit cell), are compared to experimental results.
Y1  - 2014
U6  - https://doi.org/10.1007/s00231-014-1371-8
SN  - 0947-7411 (Print) ; 1432-1181 (E-Journal)
VL  - 50
SP  - 1707
EP  - 1716
PB  - Springer
CY  - Heidelberg
ER  -