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Title A Fatigue Approach to Wind Turbine Control
Author Hammerum, Keld
Supervisor Poulsen, Niels Kjølstad (Mathematical Statistics, Informatics and Mathematical Modelling, Technical University of Denmark, DTU, DK-2800 Kgs. Lyngby, Denmark)
Institution Technical University of Denmark, DTU, DK-2800 Kgs. Lyngby, Denmark
Thesis level Master's thesis
Year 2006
Abstract Due to the turbulent nature of wind, the structural components of a wind turbine are exposed to highly varying loads. Therefore, fatigue damage is a major consideration when designing wind turbines. The control scheme applied to the wind turbine affects a subset of the loads. In this report, the basics of wind turbine control are outlined, and a summary of traditional fatigue damage estimation is given, including a treatment of SN curves and rainflow counting procedures. Spectrally based techniques providing approximate results for the fatigue damage estimate are presented. These methods describe the fatigue damage as a function of the spectral moments of the load history. This motivates the development of an efficient algorithm for computation of spectral moments of linear, stochastic processes. These methods are combined to provide efficient evaluation of a turbine performance measure taking into account fatigue damage. An application of this cost function is demonstrated through numerical optimisation of a wind turbine controller, based directly on fatigue damage design objectives.
Note Supervised in collaboration with the Loads, Aerodynamics and Control group at Vestas Wind Systems, Denmark
Series IMM-Thesis-2006-105
Original PDF imm4980.pdf (1.30 MB)
Admin Creation date: 2007-06-11    Update date: 2007-09-14    Source: dtu    ID: 200747    Original MXD