Patent ID: 11885293
Assignee: LM WIND POWER A/S
Field: Engines, pumps, turbines (Mechanical engineering)
Classification: CPC F  Y | IPC F

Claim 10:
11. An extendable wind turbine blade, comprising:
a root end and a tip end, the wind turbine blade extendable along a longitudinal axis running between the root end and the tip end;
an exterior surface with a root region and an airfoil region;
a leading edge and a trailing edge, and a chord line extending between the leading edge and trailing edge;
a first blade segment including a first portion of the exterior surface and a first end;
a second blade segment including a second portion of the exterior surface and a second end, the second blade segment being separate from the first blade segment, the first end and the second end being opposite and facing each other;
a connection device engaged between the first blade segment and the second blade segment, the connection device having a first length when the second blade segment is in a retracted state when the wind turbine blade operates above a threshold;
the connection device having a second length when the second blade segment is in an extended state when the wind turbine blade operates below the threshold;
wherein, in the retracted state, the wind turbine blade has a first length from the root end to tip end and the first portion of the exterior surface is arranged flush with and adjoining the second portion of the exterior surface;
wherein, in the extended state, the wind turbine blade has a second length from the root end to tip end and the second blade segment is arranged with a gap to the first blade segment so that the first portion of the exterior surface and the second portion of the exterior surface are disconnected;
wherein the second length is greater than the first length; and
wherein the connection mechanism comprises an actuator configured to apply an actuation force in a default state and a release state, wherein in the default state the actuator applies an actuation force that urges the second blade segment towards the first blade segment to bring the wind turbine blade to the retracted state, wherein in the release state, the actuator is configured to reduce the actuation force so that a centrifugal force overcomes the actuation force to bring the wind turbine blade to the extended state.