Lightning protection system for a wind turbine rotor blade

Abstract

A rotor blade assembly includes a first blade segment and a second blade segment extending in opposite directions from a chord-wise joint. Each of the first and second blade segments include at least one shell member defining an airfoil surface and an internal support structure. The internal support structure of the first blade segment includes a beam structure extending lengthwise that structurally connects with the internal support structure of the second blade segment via a receiving section. The beam structure includes a receiving end having a pin tube extending in a span-wise direction of the rotor blade assembly. Further, the rotor blade assembly includes a lightning protection system including a conductive mesh integrated with the beam structure and a first electrical connection electrically connecting the conductive mesh and the pin tube.

Description

LIGHTNING PROTECTION SYSTEM FOR A WIND TURBINE ROTOR BLADEFIELD

[0001] The present disclosure relates in general to wind turbine rotor blades, and more particularly to a lightning protection system for a wind turbine rotor blade.BACKGROUND

[0002] Wind power is considered one of the cleanest, most environmentally friendly energy sources presently available, and wind turbines have gained increased attention in this regard. A modem wind turbine typically includes a tower, generator, gearbox, nacelle, and one or more rotor blades. The rotor blades capture kinetic energy from wind using known foil principles and transmit the kinetic energy through rotational energy to turn a shaft coupling the rotor blades to a gearbox, or if a gearbox is not used, directly to the generator. The generator then converts the mechanical energy to electrical energy that may be deployed to a utility grid.

[0003] Wind turbine rotor blades generally include a body shell formed of a composite laminate material. In general, the body shell is relatively lightweight and has structural properties (e.g., stiffness, buckling resistance and strength) which are not configured to withstand the bending moments and other loads exerted on the rotor bade during operation. To increase the stiffness, buckling resistance and strength of the rotor blade, the body shell is typically reinforced using spar caps that engage the inner surfaces of the shell. The spar caps may be constructed of various materials, including but not limited to glass fiber laminate composites and / or carbon fiber laminate composites.

[0004] During the life of the wind turbine, the rotor blades are particularly prone to lightning strikes. In particular, when carbon fibers are used in the body shell, lightning may attach to these fibers, thereby causing severe damage to the body shell. Thus, lightning protection systems are essential to protecting wind turbine blades because of their sharp edges and insulation capabilities. Modem lightning protection system typically include one or more lightning receptors disposed on the exterior of the rotor blades and a lightning conductor or cable wire coupled to the lightning receptor(s) and extending through the body shell from a blade tip to a blade root andthrough other components until grounded down through the tower to a ground location. Accordingly, when lightning strikes the rotor blade, the electrical current flows through the lightning receptor(s) and is conducted through the lightning system to the ground. However, when a lightning strike occurs, unwanted internal arcs may arise from the spar caps to the lightning conductor, which may cause significant damage to the rotor blade.

[0005] Accordingly, the art is continuously seeking new and improved lightning protection systems for wind turbine rotor blades.BRIEF DESCRIPTION

[0006] Aspects and advantages of the present disclosure will be set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the present disclosure.

[0007] In an aspect, the present disclosure is directed to a rotor blade assembly. The rotor blade assembly includes a first blade segment and a second blade segment extending in opposite directions from a chord- wise joint. Each of the first and second blade segments include at least one shell member defining an airfoil surface and an internal support structure. The internal support structure of the first blade segment includes a beam structure extending lengthwise that structurally connects with the internal support structure of the second blade segment via a receiving section. The beam structure includes a receiving end having a pm tube extending in a span-wise direction of the rotor blade assembly. Further, the rotor blade assembly includes a lightning protection system including a conductive mesh integrated with the beam structure and a first electrical connection electrically connecting the conductive mesh and the pin tube.

[0008] In another aspect, the present disclosure is directed to a method of retrofitting a rotor blade assembly of a wind turbine with a lighting protection system. The method includes detaching a first blade segment from a second blade segment. Each of the first and second blade segments have at least one shell member defining an airfoil surface and an internal support structure. The internal support structure of the first blade segment includes a beam structure extending lengthwise that structurally connects with the internal support structure of the second blade segmentvia a receiving section. The beam structure includes a receiving end having a pin tube extending in a span- wise direction of the rotor blade assembly. The beam structure includes a first conductive mesh integrated therewith. The method also includes integrating a second conductive mesh with the beam structure. Further, the method includes electrically connecting a first end of the second conductive mesh with the first conductive mesh of the beam structure. Moreover, the method includes electrically connecting a second end of the second conductive mesh to the pm tube via a first electrical connection. The method further includes threading a ground conductor at least partially through the pin tube. In addition, the method includes electrically connecting the pin tube to ground via the ground conductor. The method also includes arranging the first blade segment with the second blade segment in opposite directions from a chord- wise joint. Further, the method includes reattaching the first and second blade segments together.

[0009] These and other features, aspects and advantages of the present disclosure will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and, together with the description, serve to explain the principles of the disclosure.BRIEF DESCRIPTION OF THE DRAWINGS

[0010] A full and enabling disclosure of the present disclosure, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which:

[0011] FIG. 1 illustrates a perspective view of one embodiment of a wind turbine according to the present disclosure;

[0012] FIG. 2 illustrates a plan view of one embodiment of a rotor blade having a first blade segment and a second blade segment according to the present disclosure;

[0013] FIG. 3 illustrates a perspective view of a section of one embodiment of the first blade segment according to the present disclosure;

[0014] FIG. 4 illustrates a perspective view of one embodiment of a section of the second blade segment at the chord-wise joint according to the present disclosure;

[0015] FIG. 5 illustrates an assembly of one embodiment of the rotor blade of thewind turbine having the first blade segment joined with the second blade segment according to the present disclosure;

[0016] FIG. 6 illustrates an exploded perspective view of one embodiment of the multiple supporting structures of the assembly of the rotor blade of the wind turbine according to the present disclosure;

[0017] FIG. 7 illustrates a partial, perspective view of an embodiment of a rotor blade according to the present disclosure;

[0018] FIG. 8 illustrates a partial, perspective view of an embodiment of an internal support structure of a rotor blade according to the present disclosure, particularly illustrating components of a lighting protection system arranged on or otherwise integrated therewith;

[0019] FIG. 9 illustrates a partial, perspective view of an embodiment of a beam structure of a rotor blade according to the present disclosure, particularly illustrating components of a lighting protection system arranged on a receiving end of the beam structure;

[0020] FIG. 10 illustrates a partial, top view of a beam structure of a rotor blade, particularly illustrating a pin flange of a pin tube on the beam structure and having a first electrical connection secured thereto;

[0021] FIG. 11 illustrates a cross-sectional view of the rotor blade of FIG. 7 at the pin tube along line 11-11;

[0022] FIG. 12 illustrates a cross-sectional view of an embodiment of a rotor blade at a location of a pin tube according to the present disclosure;

[0023] FIG. 13 illustrates a partial, perspective view of an embodiment of internal support structures of a rotor blade according to the present disclosure, particularly illustrating a pin tube positioned through a pin joint slot and defining a spark gap;

[0024] FIG. 14 illustrates another partial, perspective view of an embodiment of internal support structures of a rotor blade according to the present disclosure, particularly illustrating a pin tube positioned through a pm joint slot and defining a spark gap;

[0025] FIG. 15 illustrates a flow diagram of an embodiment of a method of retrofitting a rotor blade assembly of a wind turbine with a lighting protection systemis illustrated in accordance with aspects of the present disclosure; and

[0026] FIG. 16 illustrates a partial, cross-sectional view of an embodiment of a rotor blade that has been retrofitted with a lighting protection system in accordance with aspects of the present disclosure.DETAILED DESCRIPTION

[0027] Reference now will be made in detail to embodiments of the present disclosure, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the present disclosure, not limitation of the present disclosure. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present disclosure without departing from the scope or spirit of the present disclosure. For instance, features illustrated or described as part of one embodiment can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present disclosure covers such modifications and variations as come within the scope of the appended claims and their equivalents.

[0028] Referring now to the drawings, FIG. 1 illustrates a perspective view of one embodiment of a wind turbine 10 according to the present disclosure. In the illustrated embodiment, the wind turbine 10 is a horizontal-axis wind turbine. Alternatively, the wind turbine 10 may be a vertical-axis wind turbine. In addition, as shown, the wind turbine 10 may include a tower 12 that extends from a support surface 14, a nacelle 16 mounted on the tower 12, a generator 18 positioned within the nacelle 16, a gearbox 20 coupled to the generator 18, and a rotor 22 that is rotationally coupled to the gearbox 20 with a rotor shaft 24. Further, as shown, the rotor 22 includes a rotatable hub 26 and at least one rotor blade 28 coupled to and extending outward from the rotatable hub 26. As shown, the rotor blade 28 includes a blade tip 17 and a blade root 19.

[0029] Referring now to FIG. 2, a plan view of one of the rotor blades 28 of FIG.1 is illustrated. As shown, the rotor blade 28 may include a first blade segment 30 and a second blade segment 32. Further, as shown, the first blade segment 30 and the second blade segment 32 may each extend in opposite directions from a chord-wise joint 34. In addition, as shown, each of the blade segments 30, 32 may include atleast one shell member, such as a pressure side shell member, a suction side shell member, a leading edge shell member, a trailing edge shell member and so on. The first blade segment 30 and the second blade segment 32 are connected by at least an internal support structure 36 extending into both blade segments 30, 32 to facilitate joining of the blade segments 30, 32. The arrow 38 shows that the segmented rotor blade 28 in the illustrated example includes two blade segments 30, 32 and that these blade segments 30, 32 are joined by inserting the internal support structure 36 into the second blade segment 32.

[0030] Referring now to FIG. 3, a perspective view of a section of the first blade segment 30 according to the present disclosure is illustrated. As shown, the first blade segment 30 includes a beam structure 40 that forms a portion of the internal support structure 36 and extends lengthwise for structurally connecting with the second blade segment 32. Further, as shown, the beam structure 40 forms at least a part of a shear web 42 connected with a suction side spar beam 44 and a pressure side spar beam 46 (also referred to herein as lower and upper conductive beams).

[0031] Moreover, as shown, the first blade segment 30 may include one or more first pin joints at a receiving end 54 of the beam structure 40. In one embodiment, the pin joint may include a pin that is in a tight interference fit with a bushing. More specifically, as shown, the pin joint(s) may include one pin tube 52 located on the receiving end 54 of the beam structure 40. Thus, as shown, the pin tube 52 may be oriented in a span-wise direction, i.e., along the span or length of the rotor blade 28 which is defined along an axis that extends from the blade root to the blade tip of the rotor blade 28. Further, the first blade segment 30 may also include a pin joint slot 50 located on the beam structure 40. Moreover, as shown, the pin joint slot 50 may be oriented in a chord-wise direction, i.e., along a chord of the rotor blade 28 which is defined along an axis that extends from the leading edge to the trailing edge of the rotor blade 28.

[0032] Referring now to FIG. 4, a perspective view of a section of the second blade segment 32 according to the present disclosure is illustrated. As shown, the second blade segment 32 includes a receiving section 60 extending lengthwise within the second blade segment 32 for receiving the beam structure 40 of the first blade segment 30. Further, as shown, the receiving section 60 may include the sparstructures 66 that extend lengthwise for connecting with the beam structure 40 of the first blade segment 30. In addition, as shown, the receiving section 60 may include a chord-wise member 48 having a span-wise pin joint slot 56 defined therethrough. Moreover, as shown, the receiving section 60 may include a chord-wise pin joint slot 58 defined therethrough that aligns with the pin joint slot 50 of the beam structure 40.

[0033] Referring now to FIG. 5, an assembly 70 of the rotor blade 28 having the first blade segment 30 joined with the second blade segment 32 according to the present disclosure is illustrated. As shown, the assembly 70 illustrates multiple supporting structures beneath outer shell members of the rotor blade 28. More specifically, as shown, the span-wise extending pin 52 of the receiving end 54 of the beam structure 40 is received within the span- wise pin joint slot 56 of the receiving section 60 so as to secure the first and second blade segments 30, 32 together. In addition, as shown in FIGS. 3 and 5, each of the beam structure 40 and the receiving section 60 may define spar beams 44, 46, 53, 55, respectively, of the rotor blade 28.

[0034] Referring now to FIG. 6, an exploded perspective view of the multiple supporting structures of the assembly 70 towards the blade tip of the rotor blade 28 is illustrated. As shown, the receiving section 60 is configured to receive the beam structure 40 and may include the chord-wise pin joint slot 58 that aligns with the pin joint slot 50 of the beam structure 40 through which a chord-wise extending pin 62 may be inserted. Further, as shown, the chord-wise extending pin 62 may be configured to remain in a tight interference fit within the aligning pin joint slots 50, 58 such that the receiving section 60 and the beam structure 40 are joined together during assembly. Further, FIG. 6 also illustrates the chord-wise member 48 that includes the pin joint slot 56 configured for receiving the pin tube 52 of the beam structure 40. As such, the pin tube 52 is configured to form a tight interference fit joint.

[0035] Referring now to FIGS. 7-14, various view's of embodiments of a rotor blade, such as rotor blade 28, having a lightning protection system 100 according to the present disclosure are illustrated. FIG. 7 illustrates a partial, perspective view of the rotor blade 28 according to the present disclosure. FIG. 8 illustrates a partial, perspective view of an embodiment of the internal support structure 36 of the rotor blade 28 according to the present disclosure, particularly illustrating components of the lighting protection system 100 arranged on or otherwise integrated therewith.FIG. 9 illustrates a partial, perspective view of an embodiment of the beam structure 40 of the rotor blade 28 according to the present disclosure, particularly illustrating components of the lighting protection system 100 arranged on a receiving end of the beam structure 40. FIG. 10 illustrates a partial, top view of the beam structure 40 of the rotor blade 28, particularly illustrating a pin flange of the pin tube 52 having a first electrical connection secured thereto. FIG. 11 illustrates a cross-sectional view of the rotor blade 28 of FIG. 7 at the pin tube 52 along line 11-11. FIG. 11 illustrates a cross-sectional view of an embodiment of the rotor blade 28 at the pin tube 52 according to the present disclosure. FIGS. 13 and 14 illustrate partial, perspective views of an embodiment of internal support structures of the rotor blade 28 according to the present disclosure, particularly illustrating the pin tube 52 positioned through the pin joint slot 56 and defining a spark gap.

[0036] Furthermore, as shown in FIGS. 8 and 9, the lightning protection system 100 includes a conductive mesh 102 integrated with the beam structure 40. More specifically, in an embodiment, the conductive mesh 102 extends over an entire length of the beam structure 40. As such, in an embodiment, the conductive mesh 102 is of sufficient length to protect pultrusion members inside the beam structure 40, and therefore may act as a Faraday cage or shield. In such embodiments, for example, the conductive mesh 102 may be constructed of one of a solid sheet, a wire mesh, a webbing, a netting, or a woven sheet.

[0037] Moreover, as shown in FIGS. 8 and 9, the lightning protection system 100 may include one or more electrical connections 104, 106 electrically connecting the conductive mesh 102 and the pin tube 52, e.g., by extending from the pin tube 52 and across at least a portion of the receiving end 34 of the beam structure and to the conductive mesh 102. For example, as shown, the lightning protection system 100 includes a first electrical connection 104 and a second electrical connection 106 electrically connecting the conductive mesh 102 and the pin tube 52. In an embodiment, the first and second electrical connections 104, 106 may include flexible connectors, such flexible circuits, flexible braided circuits, flexible bus bars, flexible cables (such as braided cables), flexible bar stocks, flexible layered stacks, flexible rails, or any other suitable flexible connector. In a particular embodiment, as shown in FIGS. 8 and 9, the first and second electrical connections 104, 106 may be, forexample, flexible braided cables 108, 110, respectively. Moreover, as shown, the first and second electrical connections 104, 106 may be secured to an end of the conductive mesh 102 using any suitable means, e.g., such as soldering, mechanical fasteners, adhesives, or a combination of both.

[0038] Moreover, as shown in FIGS. 8 and 9, the pin tube 52 may generally have a pin flange 112. Thus, in an embodiment, as shown particularly in FIG. 9, the pin flange 112 may include a first tab 114 on a first side 116 ofthe pin flange 112. In such embodiments, the first electrical connection 104 is connected to the first tab 114. Furthermore, as shown, the pin flange 112 may further include a second tab 118 on an opposing, second side 120 of the pin flange 112. Thus, in an embodiment, as shown, the second electrical connection 106 is connected to the second tab 118.

[0039] Accordingly, in an embodiment, the lighting protection system 100 may also include one or more fasteners, press sleeves, and / or adhesives for securing the first and second electrical connections 104, 106 to the first and second tabs 114, 118, respectively. For example, as shown in FIG. 9, the first and second electrical connections 104, 106 are secured to the first and second tab 114, 118, respectively, via a combination of rivets 122 and electrically conductive adhesives, such as silver Loctite® (not shown). In another embodiment, as shown in FIG. 10, the first and second electrical connections 104, 106 are secured to the first and second tab 114, 118, respectively, via a rivet 122 and a press sleeve 124. In such embodiments, as shown, the lighting protection system 100 may also include an edge sealer 126 for assisting with a vacuum injection process through vacuum foil.

[0040] Moreover, as shown in FIGS. 11-14, the lightning protection system 100 further includes at least one conductor cable 128. More specifically, in an embodiment, as shown, the conductor cable(s) 128 may include a first conductor cable 136 and a down conductor 138 electrically connected to the first conductor cable 136. Furthermore, as shown, the first conductor cable 136 is electrically- connected to the pin tube 52 via a spark gap 130, whereas the down conductor 128 is electrically connected to the first conductor cable 136 through a bolt connection 134. Thus, the first and second electrical connections 104, 106 described herein may be grounded via the down conductor 138. In addition, as shown in FIG. 14, the conductor cable(s) 128 may be electrically connected to one or more lightningreceptors 132 of the lighting protection system 100.

[0041] Accordingly, in an embodiment, the conductive mesh 102 described herein is configured to generate an electric field therein to reduce a potential difference between the down conductor 138 and the lightning receptor(s) 132. As such, the conductive mesh 102, the conductor cable(s) 128, and / or the lightning receptor(s) 132 are configured to function to control the electric field caused by a lightning strike.

[0042] In an embodiment, the conductive components described herein (such as the conductive mesh 102, the first and second electrical connections 104, 106, the first and second tabs 114, 118, the pin tube 52 (in whole or in part), the conductor cable(s) 128, and / or the lightning receptor(s) 132) may be constructed of any suitable conductive material, e.g., such as copper, steel, tin, or any other suitable conductive material. Furthermore, such conductive components may have different thicknesses and / or shapes as needed to assist with the lightning current.

[0043] Referring particularly now to FIGS. 13 and 14, the lighting protection system 100 may further include a spark cap 140 arranged at least partially around the pin tube 52. More specifically, as shown, the spark gap 130 is formed between a portion of the spark cap 140 and the pin tube 52. Furthermore, as shown, the spark cap 140 may include one or more teeth 142 arranged at an interface of the spark gap 130. In such embodiments, the teeth 142 of the spark cap 140 are configured to initiate a corona discharge, which allows current to more likely jump the arc from the pin tube 52 to the spark cap 140. Moreover, in an embodiment, the pin tube 52 as described herein is a moving part that is generally inaccessible. As such, a direct electrical connection can cause maintenance issues. Accordingly, the spark gap 130 and the spark cap 140 allow the pin tube 52 to be conductive only when the arc is initiated. In other words, in an embodiment, there is not a permanent, direct electrical connection between the pm tube 52 and the spark cap 140 (and therefore the conductor cable(s) 128 to ground).

[0044] Referring now to FIGS. 15 and 16, the present disclosure is further directed to retrofitting a rotor blade assembly, such as rotor blade 28 with a lighting protection system. More specifically, as shown in FIG. 15, a flow diagram of an embodiment of a method 200 of retrofitting a rotor blade assembly of a wind turbinewith a lighting protection system is illustrated in accordance with aspects of the present disclosure. FIG. 16 illustrates a partial, cross-sectional view of an embodiment of a rotor blade that has been retrofitted with a lighting protection system in accordance with aspects of the present disclosure.

[0045] In general, the method 200 of FIG. 15 will be described herein as being implemented using a wind turbine rotor blade, such as the rotor blade 28 described herein and in reference to FIG. 16. However, it should be appreciated that the disclosed method 200 may be implemented using any other rotor blade having any lightning protection system. In addition, although FIG. 15 depicts steps performed in a particular order for purposes of illustration and discussion, the methods described herein are not limited to any particular order or arrangement. One skilled in the art, using the disclosures provided herein, will appreciate that various steps of the methods can be omitted, rearranged, combined and / or adapted in various ways.

[0046] As shown at (202), the method 200 includes detaching the first blade segment 30 from the second blade segment 32. As mentioned, each of the first and second blade segments 30, 32 have at least one shell member defining an airfoil surface and an internal support structure. Furthermore, as mentioned, the internal support structure of the first blade segment 30 may include the beam structure 40 extending lengthwise that structurally connects with the internal support structure of the second blade segment 32 via a receiving section 60. Moreover, the beam structure 40 has a receiving end with the pin tube 52 extending in a span-wise direction of the rotor blade assembly. In addition, the beam structure 40 includes a first conductive mesh 218 integrated therewith.

[0047] As shown at (204), the method 200 includes integrating a second conductive mesh 220 with the beam structure 40. As shown at (206), the method 200 includes electrically connecting a first end 222 of the second conductive mesh 220 with the first conductive mesh 218 of the beam structure 40. As shown at (208), the method 200 includes electrically connecting a second end 224 of the second conductive mesh 220 to the pm tube 52 via a first electrical connection 226. In another embodiment, the method 200 may also include electrically connecting the second end 224 of the second conductive mesh 220 to the pin tube 52 via a second electrical connection 228 in addition to the first electrical connection 226. It shouldbe understood that the first and second electrical connections 226, 228 of FIG. 16 may be configured the same as the first and second electrical connections 104, 106 of FIGS. 8-14.

[0048] Still referring to FIG. 15, as shown at (210), the method 200 includes threading a ground conductor 230 at least partially through the pin tube 52. For example, as shown in FIG. 16, the ground conductor 230 may be threaded into the pin tube 52 and secured in place via a threaded terminal 232.

[0049] In another embodiment, the method 200 may also include retrofitting the pin tube 52 with a first tab on a first side of the pin tube and / or a second tab on an opposing, second side of the pin tube 52 (as explained with reference to FIG. 9). As such, the method 200 may also include securing the first and second electrical connections 226, 228 to the first and second tabs, respectively, via one or more fasteners, a press sleeve, an adhesive, or combinations thereof. In such embodiments, and as mentioned, the first and second electrical connections 226, 228 may be a flexible circuit, a flexible braided circuit, a flexible bus bar, a flexible cable, a flexible bar stock, a flexible layered stack, a flexible rail, or similar.

[0050] As shown at (212), the method 200 includes electrically connecting the pin tube 52 to ground via the ground conductor 230, e.g., by electrically connecting the ground conductor into an existing lighting protection system. As shown at (214), the method 200 includes arranging the first blade segment 30 with the second blade segment 32 in opposite directions from a chord-wise joint. As shown at (216), the method 200 includes reattaching the first and second blade segments 30, 32 together.

[0051] In certain embodiments, the retrofit solution is used for existing rotor blades in the field, where the blade tip 17 can be removed from the blade root 19. The conductive mesh 220 can then be placed on top of the beam structure 40 as a faraday cage. The conductive mesh 220 is also electrically connected to the electrical connection 226 (e.g., braided cable) and to the ground conductor 230 through the threaded terminal 232, which is electrically connected to the one or more lighting receptors 132 (the other parallel down conductor system). In this way, lightning energy is configured to flow through the faraday cage (i.e., the conductive mesh 220) on the beam structure 40, securing it against internal flashover in the carbon pultrusions in the beam structure 40. Further, by the ground conductor 230, thevoltage is secured in two pathways, which minimizes a voltage difference securing no flashover between conductive elements.

[0052] Various aspects and embodiments of the present disclosure are defined by the following numbered clauses:

[0053] A rotor blade assembly, comprising: a first blade segment and a second blade segment extending in opposite directions from a chord- wise joint, each of the first and second blade segments comprising at least one shell member defining an airfoil surface and an internal support structure, the internal support structure of the first blade segment comprising a beam structure extending lengthwise that structurally connects with the internal support structure of the second blade segment via a receiving section, the beam structure comprising a receiving end having a pin tube extending in a span-wise direction of the rotor blade assembly; a lightning protection system, comprising: a conductive mesh integrated with the beam structure; and a first electrical connection electrically connecting the conductive mesh and the pin tube.

[0054] The rotor blade assembly of any preceding clause, wherein the pin tube comprises a pin flange, the pin flange comprising a first tab on a first side of the pin flange, the first electrical connection being connected to the first tab.

[0055] The rotor blade assembly of any preceding clause, wherein the first electrical connection comprises at least one of a flexible circuit, a flexible braided circuit, a flexible bus bar, a flexible cable, a flexible bar stock, a flexible layered stack, or a flexible rail.

[0056] The rotor blade assembly of any preceding clause, wherein the lighting protection system further comprises at least one of one or more first fasteners, a first press sleeve, or an adhesive for securing the first electrical connection to the first tab.

[0057] The rotor blade assembly of any preceding clause, wherein the lighting protection system further comprises a second electrical connection electrically connecting the conductive mesh and the pin tube.

[0058] The rotor blade assembly of any preceding clause, wherein the pin flange further comprises a second tab on an opposing, second side of the pin flange, the second electrical connection being connected to the second tab.

[0059] The rotor blade assembly of any preceding clause, wherein the second electrical connection comprises at least one of a flexible circuit, a flexible braidedcircuit, a flexible bus bar, a flexible cable, a flexible bar stock, a flexible layered stack, or a flexible rail.

[0060] The rotor blade assembly of any preceding clause, wherein the lighting protection system further comprises at least one of one or more second fasteners, a second press sleeve, or an adhesive for securing the second electrical connection to the second tab.

[0061] The rotor blade assembly of any preceding clause, wherein at least one of the conductive mesh, the first and second tabs, or the first and second electrical connections are constructed of at least one of copper, steel, or tin.

[0062] The rotor blade assembly of any preceding clause, wherein the conductive mesh extends over an entire length of the beam structure.

[0063] The rotor blade assembly of any preceding clause, wherein the lighting protection system further comprises at least one conductor cable electrically connected to the pin tube via a spark gap and one or more lightning receptors electrically connected to the at least one conductor cable.

[0064] The rotor blade assembly of any preceding clause, wherein the lighting protection system further comprises a spark cap arranged at least partially around the pin tube, and wherein the spark gap is formed between a portion of the spark cap and the pin tube.

[0065] The rotor blade assembly of any preceding clause, wherein the spark cap comprises one or more teeth arranged at an interface of the spark gap.

[0066] The rotor blade assembly of any preceding clause, wherein the rotor blade assembly is part of a wind turbine.

[0067] A method of retrofitting a rotor blade assembly of a wind turbine with a lighting protection system, the method comprising: detaching a first blade segment from a second blade segment, each of the first and second blade segments having at least one shell member defining an airfoil surface and an internal support structure, the internal support structure of the first blade segment comprising a beam structure extending lengthwise that structurally connects with the internal support structure of the second blade segment via a receiving section, the beam structure comprising a receiving end having a pin tube extending in a span-wise direction of the rotor blade assembly, the beam structure comprising a first conductive mesh integrated therewith;integrating a second conductive mesh with the beam structure; electrically connecting a first end of the second conductive mesh with the first conductive mesh of the beam structure; electrically connecting a second end of the second conductive mesh to the pin tube via a first electrical connection; threading a ground conductor at least partially through the pin tube; electrically connecting the pin tube to ground via the ground conductor; arranging the first blade segment with the second blade segment in opposite directions from a chord- wise joint; and reattaching the first and second blade segments together.

[0068] The method of any preceding clause, further comprising retrofitting the pin tube with a first tab on a first side of the pin tube, the first electrical connection being connected to the first tab.

[0069] The method of any preceding clause, further comprising securing the first electrical connection to the first tab via at least one of one or more first fasteners, a first press sleeve, or an adhesive.

[0070] The method of any preceding clause, further comprising electrically connecting the second end of the second conductive mesh to the pin tube via a second electrical connection in addition to the first electrical connection.

[0071] The method of any preceding clause, further comprising retrofitting the pin tube with a second tab on a second side of the pin tube, the second electrical connection being connected to the second tab.

[0072] The method of any preceding clause, further comprising securing the second electrical connection to the second tab via at least one of one or more second fasteners, a second press sleeve, or an adhesive.

[0073] This written description uses examples to disclose the present disclosure, including the best mode, and also to enable any person skilled in the art to practice the present disclosure, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the present disclosure is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.

Claims

WHAT IS CLAIMED IS:

1. A rotor blade assembly, comprising: a first blade segment and a second blade segment extending in opposite directions from a chord-wise joint, each of the first and second blade segments comprising at least one shell member defining an airfoil surface and an internal support structure, the internal support structure of the first blade segment comprising a beam structure extending lengthwise that structurally connects with the internal support structure of the second blade segment via a receiving section, the beam structure comprising a receiving end having a pin tube extending in a span-wise direction of the rotor blade assembly; a lightning protection system, comprising: a conductive mesh integrated with the beam structure; and a first electrical connection electrically connecting the conductive mesh and the pin tube.

2. The rotor blade assembly of claim 1, wherein the pin tube comprises a pin flange, the pm flange comprising a first tab on a first side of the pin flange, the first electrical connection being connected to the first tab.

3. The rotor blade assembly of claim 2, wherein the first electrical connection comprises at least one of a flexible circuit, a flexible braided circuit, a flexible bus bar, a flexible cable, a flexible bar stock, a flexible layered stack, or a flexible rail.

4. The rotor blade assembly of claim 2, wherein the lighting protection system further comprises at least one of one or more first fasteners, a first press sleeve, or an adhesive for securing the first electrical connection to the first tab.

5. The rotor blade assembly of claim 2, wherein the lighting protection system further comprises a second electrical connection electrically connecting the conductive mesh and the pin tube.

6. The rotor blade assembly of claim 5, wherein the pin flange further comprises a second tab on an opposing, second side of the pin flange, the second electrical connection being connected to the second tab.

7. The rotor blade assembly of claim 5, wherein the second electrical connection comprises at least one of a flexible circuit, a flexible braided circuit, aflexible bus bar, a flexible cable, a flexible bar stock, a flexible layered stack, or a flexible rail.

8. The rotor blade assembly of claim 6, wherein the lighting protection system further comprises at least one of one or more second fasteners, a second press sleeve, or an adhesive for securing the second electrical connection to the second tab.

9. The rotor blade assembly of claim 6, wherein at least one of the conductive mesh, the first and second tabs, or the first and second electrical connections are constructed of at least one of copper, steel, or tin.

10. The rotor blade assembly of claim 1, wherein the conductive mesh extends over an entire length of the beam structure.

11. The rotor blade assembly of claim 1, wherein the lighting protection system further comprises at least one conductor cable electrically connected to the pin tube via a spark gap and one or more lightning receptors electrically connected to the at least one conductor cable.

12. The rotor blade assembly of claim 11 , wherein the lighting protection system further comprises a spark cap arranged at least partially around the pin tube, and wherein the spark gap is formed between a portion of the spark cap and the pin tube.

13. The rotor blade assembly of claim 12, wherein the spark cap comprises one or more teeth arranged at an interface of the spark gap.

14. The rotor blade assembly of claim 1, wherein the rotor blade assembly is part of a wind turbine.

15. A method of retrofitting a rotor blade assembly of a wind turbine with a lighting protection system, the method comprising: detaching a first blade segment from a second blade segment, each of the first and second blade segments having at least one shell member defining an airfoil surface and an internal support structure, the internal support structure of the first blade segment comprising a beam structure extending lengthwise that structurally connects with the internal support structure of the second blade segment via a receiving section, the beam structure comprising a receiving end having a pin tube extending in a span-wise direction of the rotor blade assembly, the beam structurecomprising a first conductive mesh integrated therewith; integrating a second conductive mesh with the beam structure; electrically connecting a first end of the second conductive mesh with the first conductive mesh of the beam structure; electrically connecting a second end of the second conductive mesh to the pin tube via a first electrical connection; threading a ground conductor at least partially through the pin tube; electrically connecting the pin tube to ground via the ground conductor; arranging the first blade segment with the second blade segment in opposite directions from a chord-wise joint; and reattaching the first and second blade segments together.

16. The method of claim 15, further comprising retrofitting the pin tube with a first tab on a first side of the pin tube, the first electrical connection being connected to the first tab.

17. The method of claim 16, further comprising securing the first electrical connection to the first tab via at least one of one or more first fasteners, a first press sleeve, or an adhesive.

18. The method of claim 15, further comprising electrically connecting the second end of the second conductive mesh to the pin tube via a second electrical connection in addition to the first electrical connection.

19. The method of claim 18, further comprising retrofitting the pin tube with a second tab on a second side of the pin tube, the second electrical connection being connected to the second tab.

20. The method of claim 19, further comprising securing the second electrical connection to the second tab via at least one of one or more second fasteners, a second press sleeve, or an adhesive.

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