MSc defence Srdjan Blagojevic

Supervisors: Gunner Chr. Larsen; Albert Meseguer Urban; Jaime Yikon Liew (DTU Wind Energy)

Examiner: Bjarne Kallesøe (Siemens-Gamesa)

Title: Load implications of wake steering for wind farm de-rating
Wake steering is used in wind farms where wind turbines are yawed intentionally in order to steer the wakes. Previous research has shown to yield an increase in total wind farm energy production by steering of wakes in wind farms, whereas there is lacking research regarding load implications of wake steering, which is the focus of this thesis.

In this study of wake steering, a two-turbine array is simulated using the aeroelastic code HAWC2 with the DTU 10 MW reference turbine in order to investigate the load implications of wake steering for wind farm derating, with the main focus being on foreaft tower bottom damage equivalent loads and flapwise blade root damage equivalent loads. The power output in the two-turbine array is studied as well.

The results show that yaw steering of the upstream turbine leads to significant load reductions on the downstream turbine, as well as power output increase, albeit the steered wake is never fully deflected from the downstream turbine in an aligned two-turbine array. However, the negative effects of yawing the upstream turbine outweigh the positive effects on the downstream turbine, and with combination of the effects of yaw steering on both turbines, the load reductions are insignificant. The results also show that yaw steering in combination with derating could potentially be complementary to each other as yaw steering is most effective below rated, for the aligned two-turbine array, whereas derating is most effective at higher wind speeds.

Time

Mon 26 Aug 19
13:00 - 15:00

Organizer

DTU Vindenergi

Where

DTU Wind Energy, DTU Risø Campus, Frederiksborgvej 399, 4000 Roskilde, Meeting room Poul La Cour