초록 ▼

A partial pitch wind turbine blade in which the pitch system of the blade functions as a lightning receptor. As the pitch system is of a relatively large dimension, it is able to dissipate the effects of a lightning strike without damage, and removes the needs for additional blade features normally

A partial pitch wind turbine blade in which the pitch system of the blade functions as a lightning receptor. As the pitch system is of a relatively large dimension, it is able to dissipate the effects of a lightning strike without damage, and removes the needs for additional blade features normally used to conduct lightning around or away from the pitch system.

대표청구항 ▼

1. A partial pitch wind turbine blade comprising an inner blade extender section, an outer blade section and a pitch system, said outer blade section coupled to said inner blade extender section by said pitch system such that said outer blade section is operable to pitch relative to said inner blade

1. A partial pitch wind turbine blade comprising an inner blade extender section, an outer blade section and a pitch system, said outer blade section coupled to said inner blade extender section by said pitch system such that said outer blade section is operable to pitch relative to said inner blade extender section, wherein said pitch system comprises at least one conductive element, and wherein said partial pitch blade comprises a lightning down conductor coupled to said pitch system, and wherein said at least one conductive element of said pitch system is provided directly exposed to a lightning strike at the external surface of said pitch system thus acting as a lightning receptor for said partial pitch wind turbine blade. 2. The partial pitch wind turbine blade of claim 1, wherein the conductive element is part of the stationary part of the pitch system. 3. The partial pitch wind turbine blade of claim 1, wherein the lightning down conductor comprises a first lightning conductor provided at the inner blade extender section and a second lightning conductor provided at the outer blade section, each of the first and second lightning conductors being connected to the pitch system. 4. The partial pitch wind turbine blade of claim 1, wherein the pitch system has an inner pitch section and an outer pitch section of the pitch system where the inner and outer pitch sections are conductively connected. 5. The partial pitch wind turbine blade of claim 1, wherein said pitch system is a substantially circular pitch system of at least 2 meters diameter. 6. The partial pitch wind turbine blade of claim 1, wherein said at least one conductive element is provided about the external circumferential surface of said pitch system, and wherein the area of the external circumferential surface of said pitch system is at least 0.5 square meters. 7. The partial pitch wind turbine blade of claim 1, wherein said pitch system comprises a plurality of bearings disposed in at least one pitch system runway, and wherein the surface contact area between said bearings and the surface of said runway is selected to conduct a lightning strike through the pitch system without damaging the pitch system components. 8. The partial pitch wind turbine blade of claim 1, wherein said at least one conductive element comprises a projecting member provided on the external surface of said pitch system. 9. The partial pitch wind turbine blade of claim 8, wherein said blade comprises a plurality of projecting members evenly spaced about the external surface of said pitch system. 10. The partial pitch wind turbine blade of claim 1, wherein said at least one conductive element comprises a lightning rod provided on said pitch system. 11. The partial pitch wind turbine blade of claim 1, wherein said partial pitch blade comprises at least one shell member provided at said pitch system, wherein said at least conductive element is conductively coupled with at least one conductive member provided on the external surface of said at least one shell member. 12. The partial pitch wind turbine blade of claim 11, wherein said shell member provides an aerodynamic profile at said pitch system. 13. The partial pitch wind turbine blade of claim 1, wherein said blade comprises at least one stall fence provided at said pitch system, wherein at least one lightning receptor is provided at the distal end of said stall fence, said stall fence lightning receptor conductively coupled to said pitch system and said lightning down conductor. 14. The partial pitch blade of claim 3, wherein said second lightning conductor has a slack or flexible part connecting to the pitch system. 15. A partial pitch wind turbine comprising at least two partial pitch wind turbine blades, each of said blades comprising an inner blade extender section, an outer blade section and a pitch system, said outer blade section coupled to said inner blade extender section by said pitch system such that said outer blade section is operable to pitch relative to said inner blade extender section, wherein said pitch system comprises at least one conductive element, and wherein said partial pitch blade comprises a lightning down conductor coupled to said pitch system, and wherein said at least one conductive element of said pitch system is provided directly exposed to a lightning strike at the external surface of said pitch system thus acting as a lightning receptor for said partial pitch wind turbine blade. 16. The partial pitch wind turbine of claim 15, wherein the conductive element is part of the stationary part of the pitch system. 17. The partial pitch wind turbine of claim 15, wherein the lightning down conductor comprises a first lightning conductor provided at the inner blade extender section and a second lightning conductor provided at the outer blade section, each of the first and second lightning conductors being connected to the pitch system. 18. The partial pitch wind turbine of claim 15, wherein the pitch system has an inner pitch section and an outer pitch section of the pitch system where the inner and outer pitch sections are conductively connected.