Titel: Medium Term Evaluation of Meteorological Conditions, Power Performance and Loads on the First Swedish Offshore wind farm at Bockstigen, EWEA Offshore Conference 2001
Författare/Author: Hans Ganander, Sten Dahlman, Göran Ronsten, Hans Bergström
Utgivare/Publisher: Vindforsk
Årtal/Year: 2001
Ämnesord/Subject: meteorologi
Sökord/Keywords: offshore, Bockstigen, monopile
Rapport (Pdf)
Sammanfattning/Abstract: The first offshore wind farm in Sweden; Bockstigen, consists of five 500 kW stall controlled wind turbines on monopile foundations. The main objectives of the technical evaluation are to a) verify the original design assumptions made for a load carrying monopile and bedrock, b) investigate offshore power production versus onshore ditto as well as to determine park effects and c) analyse meteorological multi-mast statistics which serve as reference data to a newly developed computer
code for offshore wind energy potential mapping. The “main” measurement system has continuously been acquiring data at 1 and 20 Hz/channel since the summer of 1998. A 40 m meteorological mast was built within the wind farm in the summer of 1999 in order to acquire relatively undisturbed wind speed data from “free” sectors as well as to enable wake measurements. The monopile and tower of one of the turbines are equipped with strain gauges at several depths and heights. Earlier, [1] and [2], the objective was limited to verify the design integrity based on measured dynamic response of the tower and static
loads in extreme situations. In this paper, and in addition to power performance and meteorology, the influence of wind direction on load variation contributions from wind and waves is presented.