Lightning protection system for wind turbine blades with conducting structural components

Patent metadata

Field	Value
Publication number	US-10125744-B2
Application number	US-201615137159-A
Country	US
Kind code	B2
Filing date	Apr 25, 2016
Priority date	May 8, 2015
Publication date	Nov 13, 2018
Grant date	Nov 13, 2018

Abstract

The invention provides a lightning protection system for a wind turbine blade (10), whose structure comprises two structural shells (11, 13) with two caps (19, 21) formed by carbon fiber laminates and two spars (15, 17). In addition to a first subsystem formed by one or more lightning receptors connected to one or two conductor cables the lightning protection system comprises a second subsystem formed by lateral lightning receptors (30, 31) arranged at the leading and trailing edges of the wind turbine blade (10) in at least two cross sections (22, 23) of it connected with the caps (19, 21) and connecting means between the two subsystems for equipotentializing the lightning protection system.

First claim

The invention claimed is:

1. Lightning protection system of a wind turbine blade ( 10 ), whose structure comprises two structural shells ( 11 , 13 ) including two caps ( 19 , 21 ) formed by carbon fiber laminates and two spars ( 15 , 17 ), comprising:
a first subsystem comprising one or more lightning receptors ( 25 , 25 ′) connected to a first conductor cable ( 41 ) disposed inside of the wind turbine blade ( 10 ) for driving lightning to ground;
a second subsystem comprising connecting means between the caps ( 19 , 21 ) and the first conductor cable ( 41 ) allowing equipotentializing the lightning protection system in at least two cross sections ( 22 , 23 ) of the wind turbine blade ( 10 );
characterized in that:
the second subsystem also comprises in each of said cross sections ( 22 , 23 ) a first lateral lightning receptor ( 31 ) arranged on one edge of said cross sections ( 22 , 23 ) including first internal conducting blocks ( 36 , 37 ) in the structural shells ( 11 , 13 ) and first external connectors ( 56 , 57 ) configured so that they can interconnect electrically the first internal conducting blocks ( 36 , 37 );
the first internal conducting blocks ( 36 , 37 ) are connected to the caps ( 19 , 21 ) by first auxiliary cables ( 46 , 47 );
the first conductor cable ( 41 ) is connected to one of the first auxiliary cables ( 46 , 47 ) via a second auxiliary cable ( 53 ).

2. Lightning protection system according to claim 1 , wherein the terminals of the caps ( 19 , 21 ) to which said first auxiliary cables ( 46 , 47 ) are connected are metal plates.

3. Lightning protection system according to claim 1 , wherein the first lightning conductor cable ( 41 ) is attached to one of the spars ( 15 , 17 ) of the wind turbine blade ( 10 ).

4. Lightning protection system according to claim 1 , wherein one of the first external connectors ( 56 , 57 ) is dimensioned to contact with the first internal conducting blocks ( 36 , 37 ).

5. Lightning protection system according to claim 1 , wherein:
the first subsystem further comprises a second conductor cable ( 43 ) arranged inside of the wind turbine blade ( 10 ) for driving lightning to ground;
the second subsystem further comprises in each of said cross sections ( 22 , 23 ) a second lateral lightning receptor ( 30 ) arranged at the edge of said cross sections opposite to the edge of the first lateral lightning receptor ( 31 ) that includes second internal conducting blocks ( 34 , 35 ) in the structural shells ( 11 , 13 ) and second external connectors ( 54 ; 55 ) configured so that they allow to interconnect electrically the second internal conducting blocks ( 34 , 35 );
the second internal conducting blocks ( 34 , 35 ) are connected to the caps ( 19 , 21 ) by third auxiliary cables ( 44 , 45 );
the second conductor cable ( 43 ) is connected to one of said third auxiliary cables ( 44 , 45 ) by a fourth auxiliary cable ( 53 );
the second subsystem further comprises an equipotential bar ( 50 ) connected to the first and second conductor cables ( 41 , 43 ).

6. System according to claim 5 , wherein the terminals of caps ( 19 , 21 ) to which said third auxiliary cables ( 44 , 45 ) are connected are metal plates.

7. System according to claim 5 , wherein the second conductor cable ( 43 ) is attached to the one of the spars ( 15 , 17 ) of the wind turbine blade ( 10 ) to which is not attached the first lightning conductor cable ( 41 ).

8. Method of installing a lightning protection system according to claim 1 in a wind turbine blade ( 10 ) whose structure comprises two structural shells ( 11 , 13 ) including two caps ( 19 , 21 ) formed by carbon fiber laminates and two spars ( 15 , 17 );
the manufacturing process of the wind turbine blade ( 10 ) comprising a first stage of manufacturing said caps ( 19 , 21 ), a second stage of manufacturing the structural shells ( 11 , 13 ) with said caps ( 19 , 21 ) embedded therein; a third stage of joining the spars ( 15 , 17 ) to the lower structural shell ( 13 ) and a fourth stage of joining the two structural shells ( 11 , 13 );
characterized by comprising the following steps:
a) including conducting terminals in the caps ( 19 , 21 ) in the first stage;
b) mounting in each of said cross sections ( 22 , 23 ) the first internal conducting blocks ( 36 , 37 ) of the first lateral lightning receptor ( 31 ) during the second stage and after it connect them to the caps ( 19 , 21 ) by the first auxiliary cables ( 46 , 47 );
c) attaching the first conductor cable ( 41 ) to the spar ( 17 ) closest to the first lateral lightning receptor ( 31 ) and connect it to the first auxiliary cable ( 47 ) through the second auxiliary cable ( 51 ) in the third stage;
d) interconnect the first internal conducting blocks ( 36 , 37 ) by means of the first external connectors ( 56 , 57 ) in the fourth stage.

9. Method of installing a lightning protection system according to claim 5 in a wind turbine blade ( 10 ) whose structure comprises two structural shells ( 11 , 13 ) including two caps ( 19 , 21 ) formed by carbon fiber laminates and two spars ( 15 , 17 );
the manufacturing process of the wind turbine blade ( 10 ) comprising a first stage of manufacturing said caps ( 19 , 21 ), a second stage of manufacturing the structural shells ( 11 , 13 ) with said caps embedded therein, a third step of joining the spars ( 15 , 17 ) to the lower shell ( 13 ) and a fourth step of joining the two structural shells ( 11 , 13 );
characterized by comprising the following steps:
a) including conductive terminals in the caps ( 19 , 21 ) in the first stage;
b) mounting in each of said cross sections ( 22 , 23 ) the first and second internal conducting blocks ( 34 , 35 ; 36 , 37 ) of the first and second lateral lightning receptors ( 30 , 31 ) during the second stage and after it connecting them to the caps ( 19 , 21 ) through the first auxiliary cables ( 46 , 47 ) and the third auxiliary cables ( 44 , 45 );
c) attach the first and second conductor cables ( 41 , 43 ) to the spars ( 15 , 17 ), mounting the equipotential bar ( 20 ) between them and connect them, respectively, to the first and third auxiliary cable ( 47 , 45 ) by the second and fourth auxiliary cable ( 51 , 53 ) in the third stage;
d) interconnect the first and second internal conducting blocks ( 36 , 37 ; 34 , 35 ) through the first and second external connectors ( 56 , 57 ; 54 , 55 ) in the fourth stage.

Assignees

• Gamesa Innovation & Tech Sl

Inventors

• March Nomen Victor
• Bandres Gomez Francisco Javier
• Iriarte Eleta Javier

Classifications

• F03D80/30 Primary

  Lightning protection · CPC title

• F05B2280/6003

  Composites; e.g. fibre-reinforced · CPC title

• F05B2280/2006

  Carbon, e.g. graphite · CPC title

• F03D13/10

  Assembly of wind motors; Arrangements for erecting wind motors · CPC title

• F03D1/0675 Primary

  of the blades · CPC title