Aalborg Universitet Wind Energy Systems and Technologies, Aalborg University Frigaard, Peter Bak Publication date: 2007 Document Version Publisher's PDF, also known as Version of record Link to publication from Aalborg University Citation for published version (APA): Frigaard, P. (2007). Wind Energy Systems and Technologies, Aalborg University. Aalborg: Department of Civil Engineering, Aalborg University. General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. ? Users may download and print one copy of any publication from the public portal for the purpose of private study or research. ? You may not further distribute the material or use it for any profit-making activity or commercial gain ? 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Downloaded from vbn.aau.dk on: September 29, 2016 Faculty of Engineering, Science and Medicine - Aalborg University Wind Energy Systems and Technologies Aalborg University Research areas: • Energy planning • Power electronics and power systems • Control • Blade design – composite materials • Aerodynamics and aeroelasticity • Structural dynamics • Foundation • Load and safety Master and PhD programs in wind energy Offshore wind turbine at Aalborg Østhavn Faculty of Engineering, Science and Medicine - Aalborg University Department of Energy Technology Research Focus in Wind Turbine Systems: Control System Rotor Wind Energy Gearbox Generator Power electronics Mechanical Energy Transformer Grid Electrical Energy Grid Requirements! Faculty of Engineering, Science and Medicine - Aalborg University Research Projects Examples of Project : • • • • • • • • Stability and control of Wind farms in Power Systems Integration and Control of Wind Farms in the Danish Electricity System Offshore Wind Power Grid Connection and Reliability Operation and control of distribution systems with high level integration of renewable generation units Modeling and Control of Grid Converter Simulation Platform for Wind Turbines Monitoring and Advanced Control of Three Phase DPGS Project Advanced Power Converter for UNIversal and FLEXible Power Management in Future Electricity Network (EU) Faculty of Engineering, Science and Medicine - Aalborg University Simulation Platform Home Page for Simulation Platform Project: http://www.iet.aau.dk/Research/spp.htm Faculty of Engineering, Science and Medicine - Aalborg University Department of Electronic Systems - Section for Automation & Control Current wind energy activities: • Industrial study group in model based control of wind turbines • Research in connection with MSc projects • Industrial PhD project regarding robust control of wind turbines • Industrial PhD project regarding model predictive control of wind turbines Faculty of Engineering, Science and Medicine - Aalborg University Department of Mechanical Engineering Wind energy activities: • • Almost exclusively devoted to characterisation, modelling/analysis, design and optimization of advanced composite materials and sandwich structures for wind turbine blades Several ongoing and recent projects with partners in wind energy sector (wind turbine blade manufacturers, material suppliers, research institutions) Faculty of Engineering, Science and Medicine - Aalborg University Examples of research projects “Structural Instability Phenomena in Wind Turbine Blades” Objectives: • Characterisation and modelling of buckling phenomena in wind turbine blades: Faculty of Engineering, Science and Medicine - Aalborg University “Buckling of wind turbine rotor blades: Analysis, design and experimental validation” Industrial Ph.D. project with Vestas Wind Systems A/S - 2002-2007 Objectives: • Development of analysis tools for the prediction of local buckling. • Analytical (closed-form) and numerical methods. • Verification/validation of analysis results through comparison with experimenatal data obtained form model tests as well as full scale tests. • Structural design optimization of wing/blade. Faculty of Engineering, Science and Medicine - Aalborg University 9 m test section – 4 pt. bending Faculty of Engineering, Science and Medicine - Aalborg University Department of Civil Engineering Wind energy activities: • • • Loads and safety – risk analysis Foundation – geotechnics Wave and current loads - scour Faculty of Engineering, Science and Medicine - Aalborg University Load & Safety – Risk analysis Probabilistic design of wind turbines: • Reliability & risk analysis of components using probabilistic methods: – Blades + hub + tower + foundation – Gearboxes, generators, … • Reliability updating using measurements / condition monitoring • Probabilistic adjustment of safety factors using test results etc. Faculty of Engineering, Science and Medicine - Aalborg University Load & Safety – Risk analysis Risk-based operation & maintenance of offshore wind turbines: Key aspects: • Reliability - Availability • Maintenance costs • Energy production (benefits) Offshore: • Weather windows • Availability of transport and equipment Probabilistic approach Probabilistic approach Optimal decisions: Minimum total expected costs in lifetime Experience from RBI for offshore oil & gas structures Faculty of Engineering, Science and Medicine - Aalborg University Foundation and Geotechnics • Soil - Structure interaction of foundations for offshore wind turbines • Wind-turbine footings on layered ground • Verification by tests – Laboratory model test – Field trials at reduced scale – Full-scale tests and measurements Faculty of Engineering, Science and Medicine - Aalborg University Foundation and Geotechnics Soil - Structure interaction of foundations for offshore wind turbines: gravity based foundation - bucket foundation - monopile foundation - tripod foundation Faculty of Engineering, Science and Medicine - Aalborg University Foundation and Geotechnics Wind-turbine footings on layered ground: Faculty of Engineering, Science and Medicine - Aalborg University Foundation and Geotechnics Laboratory tests: Faculty of Engineering, Science and Medicine - Aalborg University Foundation and Geotechnics Test site for offshore wind turbine research in Frederikshavn: Faculty of Engineering, Science and Medicine - Aalborg University Foundation and Geotechnics Test site for offshore wind turbine research in Frederikshavn: Faculty of Engineering, Science and Medicine - Aalborg University Wave and current loads - Scour Characterization of the environmental loads related to the offshore position: In order to evaluate the structure •Waves; irregular breaking •Currents; wave generated / tidal •Loads from wave/current •Loads from ice •Erosion holes (Scour) •Scour protection Faculty of Engineering, Science and Medicine - Aalborg University Wave and current loads - scour Wave Run-up Height (level) of Spray Slamming forces on Boat Landings Total Wave Forces on Shaft Laboratory tests: Faculty of Engineering, Science and Medicine - Aalborg University Measurements of Scour hole in laboratory test (Pile removed) Area:1.5 m x 0.93 m Step:1.5 cm Time:35 min Faculty of Engineering, Science and Medicine - Aalborg University Wave and current loads - scour Comparative tests with Scour Protection: Faculty of Engineering, Science and Medicine - Aalborg University Contacts Energy: www.iet.aau.dk/ Assoc. Professor John K. Pedersen: jkp@iet.aau.dk Control: www.control.aau.dk Professor Jakob Stoustrup: jakob@es.aau.dk Mechanical: www.ime.auc.dk Professor Ole Thybo Thomsen: ott@ime.aau.dk Civil Engineering: Professor John Dalsgaard Sørensen jds@civil.aau.dk