10089_001.pdf - Load set calculation - ECN

Load set calculation DOWEC 6MW H. Efdé
Contents
Quality.....................................................................................................................................................2
Summary.................................................................................................................................................3
Contents..................................................................................................................................................4
1 Introduction ......................................................................................................................................5
2 Wind turbine .....................................................................................................................................6
2.1 Wind turbine modelling ........................................................................................................... 6
3 Load set. ..........................................................................................................................................7
3.1 Introduction. ............................................................................................................................ 7
3.2 Definitions of the quantities..................................................................................................... 7
3.3 Forces, moments and deflections........................................................................................... 8
3.4 User defined parameters ........................................................................................................ 9
4 Results...........................................................................................................................................11
4.1 Maximum tower foot bending moment ................................................................................. 11
4.2 Extreme tables...................................................................................................................... 12
4.3 1 Hz equivalent signals......................................................................................................... 13
5 Design variations. ...........................................................................................................................15
5.1 Cost of energy....................................................................................................................... 15
5.2 Structural pitch...................................................................................................................... 15
5.2.1 Cost of energy. .............................................................................................................. 16
5.3 Tower eigenfrequencies. ...................................................................................................... 17
5.3.1 Cost of energy. .............................................................................................................. 17
5.4 Turbine control. ..................................................................................................................... 18
5.4.1 Cost of energy. .............................................................................................................. 18
5.5 Tapered blade....................................................................................................................... 20
5.5.1 Cost of energy. .............................................................................................................. 20
5.6 Low Lambda control. ............................................................................................................ 21
5.6.1 Cost of energy. .............................................................................................................. 22
6 Conclusion. ....................................................................................................................................23
References. ...........................................................................................................................................24
Appendix A. Phatas file listing ..........................................................................................................25
Appendix B. Load cases listing.........................................................................................................26
Appendix C. Plot of loadcase GrEog1Voc.........................................................................................31
Appendix D. Tables structural pitch. .................................................................................................32
Appendix E. Tables tower frequencies..............................................................................................41
Appendix F. Tables pitch control. .....................................................................................................50
Appendix G. Tables tapered blade....................................................................................................59
Appendix H. Low Lambda control. ....................................................................................................68
Appendix I. Plots tower eigenfrequencies. ..........................................................................................69
Appendix J. Base line control versus Peak Shave control. ...............................................................72
R45.04/01.03/03 Stentec, 3-1-03 page 4