Första steget mot ett egenutvecklat litet vindkraftverk : Framtagning av ett vindkraftsblad

Abstract:

Wind power is a mature market for large wind turbines but the small wind turbine market is still an open one. There is only one player of considerable size on the small wind market: the market leader Southwest Windpower. Now Skyllermarks Pressar AB (hereafter referred to as Skyllermarks) wants to develop a more competitive turbine than Southwest Windpower’s Skystream 3.7. The first step in this project is to develop a blade for injection moulding for FuturEnergy’s FE10XX turbine.

Skyllermarks is a reseller for the English small wind turbine manufacturer FuturEnergy. As a first step towards developing a new turbine the aim of this theisis is to provide the backbone for developing a new wind turbine blade for FuturEnergys FE10XX turbine. The turbine is a fixed pitch, variabel speed machine with a rotordiameter of 1.75 m. It uses furling for overspeed protection.

Southwest Windpower is Skyllermarks’s main competitor as the market leader in the small wind sector. Because of this, Southwest Windpower’s turbine Skystream 3.7 is used as a basis for comparsion for the FE10XX. It is found that the FE10XX turbine should be able to provide the desired annual energy production of 2000 kWh for a average wind speed of 4 to 6 m/s if the rotordiameter is expanded to 3.6 m. The blade profile family S822 or S833 from NREL should be used for the new blade. To make the turbine quieter the optimal tip speed ratio of the blades should be reduced from the present 5.5 to 4.5. The tip shape of the blade also has an impact on the sound and therefore a tip shape with a sweept leading edge is recomended. Is is concluded that the new blade can be produced in the largest injection moulding machine at Skyllermarks’s plastic mouldning partner Accenta Plast.

At the price of added complexity the rotor can be improved further by adding vortex generators to make the blades more efficient and quiet and by using PETD technology for de-icing the blades.