Wind turbine and wind turbine blade
AssigneeEnvision Energy (Denmark) ApS
InventorsPeter Grabau, Michael Friedrich
Life of this patent
Estimating the term…
Abstract
A partial pitch wind turbine is described wherein the wind turbine blade has an inner blade section designed for stall-controlled operation and an outer blade section designed for pitch-controlled operation. The different blade profiles for the different sections allow for the efficient operation of the blade while providing for the control of the wind turbine to effectively reduce blade root moments. The outer blade sections can be pitched out of the wind to reduce root moments due to the outer blade sections, while the increasing power capture of the inner blade section maintains nominal power output.
Claims15
A partial pitch wind turbine blade of at least 35 meters length, the blade comprising:
- an inner blade section;
- an outer blade section coupled to said inner blade section at a pitch junction, said outer blade section operable to pitch relative to said inner blade section, wherein
- said inner blade section comprises a first blade profile for a stall-controlled aerodynamic blade with a first aerodynamic profile having a first maximum lift coefficient (CLmax1) and a first cord (Ch1) at the end facing said pitch junction and wherein
- said outer blade section comprises a second blade profile for a pitch-controlled aerodynamic blade with a second aerodynamic profile having a second maximum lift coefficient (CLmax2) and a second cord (Ch2) at the end facing said pitch junction, and
- wherein said blade comprises a discontinuity between said first and second blade profiles between said pitch junction, which discontinuity is such that [(CLmax1)×(Ch1)] is at least 20% greater than [(CLmax2)×(Ch2)].
Dependencies are inferred from the claim text.