Patent Publication Number: US-2023142518-A1

Title: Wind blade having a lightning protection system

Description:
BACKGROUND 
     Embodiments of the present specification generally relate to a lightning protection subsystem. In particular, the present specification discloses a lightning protection subsystem disposed along an edge of a wind blade, on an outer surface of the wind blade. The present disclosure also relates to method of installation of lightning protection subsystem along the edge of the wind blade. 
     It may be noted that lightning protection subsystem typically includes conductors/cables disposed in inner cavity of the wind blade. More specifically, the lightning conductors/cables are disposed along the shear web of the wind blade. Since, the lightning conductors/cables are disposed in the inner cavity of the wind blade, it is difficult to access the lightning conductors/cables. In case of failures in the lightning conductors/cables, it is difficult to access and repair the lightning conductors/cables. Manholes may need to be provided on wind blade surface to access the lightning conductors disposed in the inner cavity. These manholes/access panels are large holes on the wind blade surface and may in turn impact structural integrity of the wind blade. 
     In recent times, use of the lightning conductor/cables on the outer surface of the wind blade is disclosed. However, these lightning conductors/cables affect the aerodynamic profile of the wind blade. Accordingly, the aerodynamic performance of the wind blade is affected. 
     Moreover, generally, the lightning conductors/cables are long continuous cables. Hence, in the case of modular/split blades if a single continuous cable is employed as the lightning conductor, the transportation of different sections of the wind blades separately is not feasible. This in turn adds to the complexity of transport of long wind blades. 
     It is also known to integrate down conductors into the leading edge and/or the trailing edge of the wind turbine blade. However, such systems have the same problems as lightning protection systems with an internal down conductor and are further difficult to service. 
     BRIEF DESCRIPTION 
     In accordance with aspects of the present specification, a lightning protection subsystem for a wind blade is presented. The lightning protection subsystem includes one or more conductive segments, where each of the one or more conductive segments include a conductor and a coupling portion. The coupling portion is configured to secure the one or more conductive segments to an edge of the wind blade. Further, the one or more conductive segments form an elongated lightning conducting path along at least a portion of the length of the edge, at an outer surface of the wind blade. 
     In accordance with yet another aspect of the present specification, a method of manufacturing a wind blade having a lightning protection subsystem is presented. The method of manufacturing the wind blade includes moulding at least a portion of a wind blade and disposing one or more conductive segments along at least a portion of length of an edge of the wind blade, where the one or more conductive segments include a conductor and a coupling portion, where the coupling portion is configured to secure the one or more conductive segments to the edge of the wind blade, and where the one or more conductive segments form an elongated lightning conducting path along at least a portion of a length of the edge, at an outer surface of the wind blade. 
     In a preferred embodiment, the lightning protection subsystem may further include a plurality of connecting segments, where at least one connecting segment of the plurality of connecting segments is disposed between two conductive segments of the one or more conductive segments. 
     In a further preferred embodiment, the elongated lightning conducting path includes a lightning conductor, a lightning conducting cable, or a combination thereof. In another preferred embodiment, an airgap exists between at least two conductive segments, and wherein the airgap aids in conduction of electrical current. 
     In another preferred embodiment, the plurality of connecting segments is made of flexible material. 
     In another preferred embodiment, the one or more conductive segments comprise an outer covering wrapping at least partially the conductor, and wherein the outer covering comprises an insulator. 
     In another preferred embodiment, the insulator comprises composites, a thermoplastic material, or a combination thereof. 
     In another preferred embodiment, the one or more conductive segments are configured to provide a desired aerodynamic profile of the wind blade. 
     In another preferred embodiment, first dimensions of the one or more conductive segments vary along the length of the edge of the wind blade. 
     In another preferred embodiment, the first dimensions of the one or more conductive segments comprise at least one of height, length, and width of the one or more conductive segments. 
     In another preferred embodiment, the one or more conductive segments have a tapering geometry. 
     In another preferred embodiment, the one or more conductive segments comprise at least one of carbon fibres and conductive metals. 
     In another preferred embodiment, at least one conductive segment of the one or more conductive segments is disposed at a tip end of the wind blade. 
     In another preferred embodiment, at least one conductive segment disposed at the tip end of the wind blade acts as a toroid of the lightning protection subsystem. 
     In another preferred embodiment, the edge of the wind blade is at least one of a leading edge and a trailing edge. The conductive segments may advantageously have a substantially triangular cross-section for arrangement at the trailing edge of the wind blade. 
     In another preferred embodiment, the coupling portion of the one or more conductive segments comprises one or more first attachment subunits. 
     In another preferred embodiment, the one or more conductive segments form a portion of an aerofoil surface of the wind blade. 
     In one embodiment, a wind blade comprising a lightning protection subsystem. 
     In another embodiment, one or more conductive segments are secured to the edge of the wind blade using an adhesive. 
     In a preferred embodiment, the wind blade comprises one or more receiving units along the edge of the wind blade. 
     In another preferred embodiment, the coupling portion of each of the one or more conductive segments is received in the corresponding receiving unit of the one or more receiving units. 
     In another preferred embodiment, second dimensions of the one or more receiving units complement the first dimensions of the one or more conductive segments. 
     In yet another preferred embodiment, the second dimensions of the one or more receiving units comprises at least of depth, length, and width of the one or more receiving units. 
     In another preferred embodiment, moulding at least the portion of the wind blade includes forming one or more receiving units along an edge of the wind blade. 
     It is clear that the conductive segments are preferably connected to an exterior of the wind blade. Further, it is clear that the system is modular and that a plurality of the conductive segments may form a down conductor of the lightning protection system. The conductive segments may further be electrically connected to one or more receptors, or one or more of the conductive segments may function as a receptor. This makes the system easy and cost-effective to service, e.g. after a lightning strike, where part of the lightning protection system or blade may be damaged. The conductive segments may advantageously each have a longitudinal extent of 50-500 cm, preferably 50-250 cm. 
    
    
     
       DRAWINGS 
       These and other features, aspects, and advantages of the present disclosure will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein: 
         FIG.  1    illustrates conventional modern upwind wind turbine; 
         FIG.  2    is a diagrammatical representation of a wind blade with a lightning protection subsystem; 
         FIG.  3    is a detailed diagrammatical representation of at least a portion of the lightning protection subsystem disposed on a trailing edge of the wind blade; 
         FIG.  4    is a diagrammatical representation of one embodiment of a conductive segment employed in the lightning protection subsystem of  FIG.  3   ; 
         FIG.  5    is a diagrammatical representation of the trailing edge of the wind blade of  FIG.  2   ; 
         FIG.  6    is a diagrammatical representation of at least a portion of the lightning protection subsystem disposed on a leading edge of the wind blade; 
         FIG.  7    is a diagrammatical representation of one embodiment of a conductive segment employed in the lightning protection subsystem of  FIG.  6   ; 
         FIG.  8    is a diagrammatical representation of another embodiment of a conductive segment employed in the lightning protection subsystem of  FIG.  6   ; 
         FIG.  9    is another diagrammatical representation of the embodiment of  FIG.  8   ; and 
         FIG.  10    is a flow chart representation of a method of manufacturing a wind blade having a lightning protection subsystem. 
     
    
    
     DETAILED DESCRIPTION 
     Unless defined otherwise, technical and scientific terms used herein have the same meaning as is commonly understood by one of ordinary skill in the art to which this specification belongs. The terms “first”, “second”, and the like, as used herein do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. Also, the terms “a” and “an” do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced items. The use of “including,” “comprising” or “having” and variations thereof herein are meant to encompass the items listed thereafter and equivalents thereof as well as additional items. The terms “connected” and “coupled” are not restricted to physical or mechanical connections or couplings, and can include electrical connections or couplings, whether direct or indirect. 
     As will be described in detail hereinafter, various embodiments of a wind blade having a lightning protection subsystem and method of manufacturing a wind blade having a lightning protection subsystem are disclosed. As will be appreciated, the lightning protection subsystem includes lightning conducting cable, toroid, and lightning receptors. The present specification discloses use of conductive segments to form a lightning conducting path along an edge of the wind blade. The edge of the wind blade may include a leading edge of the wind blade, a trailing edge of the wind blade, and the like. Although the present specification describes some embodiments of the conductive segments, use of other embodiments of conductive segments to form a lightning conducting path is also anticipated. 
     In accordance with the embodiments of the present specification, the lightning conducting path is formed using one or more conductive segments disposed on an outer surface of the wind blade. Accordingly, it is relatively easy to access the lightning conducting path. Easier accessibility of the lightning conducting path enables hassle-free repair of the lightning conducting path in the event of a fault. Further, since the lightning conducting path is on outer surface of the wind blade, need of large manholes or hatches to access the lightning conducting cable is avoided. Furthermore, since the lightning conducting path may be formed using the conductive segments instead of a single long conductive cable, the proposed lightning conducting path is also suitable for modular blades/split blades. This in turn allows a comparatively easier transport of the modular blades/split blades. 
       FIG.  1    illustrates a conventional modern upwind wind turbine  2  according to the so-called “Danish concept” with a tower  4 , a nacelle  6  and a rotor with a substantially horizontal rotor shaft. The rotor includes a hub  8  and three blades  10  extending radially from the hub  8 , each having a blade root  16  nearest the hub and a blade tip  14  furthest from the hub  8 . 
       FIG.  2    is a diagrammatical representation  100  of a wind blade with a lightning protection subsystem in accordance with an embodiment of the present specification. A wind blade  101  includes an edge. In one example, the edge may include at least one of a trailing edge  102  and a leading edge  104 . Reference numeral  106  represents an outer surface of the wind blade  101 . Further, reference numeral  108  represents an inner surface of the wind blade  101 . 
     In the example of  FIG.  2   , elongated lightning conducting paths  110  and  111  are disposed on the outer surface  106  of the wind blade  101 . In one embodiment, the lightning conducting paths  110 ,  111  may be a lightning conducting cable, lightning conductor, down conductor and the like. The lightning conducting path  110  is disposed on outer surface  106  along the trailing edge  102  of the wind blade  101 . More specifically, the lightning conducting path  110  is disposed along length of the trailing edge  102  of the wind blade  101 . In another embodiment, the lightning conducting path  111  may be disposed along the leading edge  104  of the wind blade  101 . Since, the lightning conducting paths  110  and  111  are disposed on the outer surface  106 , it is easier to access the lightning conducting paths  110 ,  111  in the event of a fault. 
     In one embodiment, the lightning conducting paths  110 ,  111  are made of one or more conductive segments. The structure of the lightning conducting path  110  may be depicted in greater detail with respect to subsequent figures. Although the example of  FIG.  2    represents two lightning conducting paths  110 ,  111  along the respective edges, use of only one of the lightning conducting paths  110  and  111  along any one of the edges of the wind blade is anticipated. Specifically,  FIGS.  3 - 5    disclose the conductive segments  202  disposed along trailing edge of the wind blade. Further,  FIGS.  6 - 9    represent conductive segments disposed along leading edge of the wind blade. 
       FIG.  3    is a detailed diagrammatical representation  200  of at least a portion of the lightning protection subsystem disposed on a trailing edge of the wind blade. The wind blade  101  includes the trailing edge  102  and the leading edge  104 . In this example, the wind blade  101  is manufactured in such a manner that the trailing edge  102  is a band of flatter surface when compared to existing wind blades. Specifically, the trailing edge  102  includes one or more receiving units (not shown in  FIG.  3   ). The receiving units at the trailing edge  102  of the wind blade is described in detail with respect to  FIG.  5   . 
     In the example of  FIG.  3   , the lightning conducting path  110  is made of one or more conductive segments  202  disposed adjacent to one another. The one or more conductive segments  202  are couplable to the trailing edge  102 . Specifically, each of the conductive segments  202  may be received in the corresponding receiving units of the wind blade  101 . Once the conductive segments  202  are coupled to the trailing edge  102  a desired aerodynamic profile of the trailing edge of the wind blade  101  is achieved. Accordingly, the conductive segments  202  may form a portion of aerofoil surface of the wind blade. The term ‘aerofoil surface,’ as used herein, refers to a finished aerodynamic shell of the wind blade. 
     In one embodiment, each of the conductive segments  202  include a coupling portion  203 . The coupling portion  203  is configured to secure the one or more conductive segments  202  to the edge  102  or  104  of the wind blade  101 . In one embodiment, the coupling portion  203  is a portion of the conductive segment  202  which may be proximate and in physical contact with the edge  102  or  104  of the wind blade  101 . 
     In the example of  FIG.  2   , the coupling portion  203  includes a first attachment subunit  204 . The first attachment subunit  204  aids in coupling of the conductive segments  202  to the trailing edge  102  of the wind blade  101 . Specifically, the conductive segments  202  is securely received in the respective receiving units (not shown in  FIG.  2   ) at the trailing edge  102  of the wind blade  101 . In addition, the conductive segments  202  may be coupled to the trailing edge  102  of the wind blade  101  using adhesive, glue, double sided adhesive tapes, fasteners, clip-on mechanism, click mechanism, rail-based mechanism, and the like. 
     The conductive segments  202  includes a conductor. In one example, the conductor includes a carbon fibre, other conductive metals, and the like. The conductive metals may include at least one of copper and aluminium. In one embodiment, the conductive segment  202  includes a conductor may be at least partially covered by an outer covering. This outer covering may be an insulator, such as but not limited to composites, thermoplastics, and the like. 
     Additionally, the lightning conducting path  110  includes a plurality of connecting segments  206 . In one embodiment, at least one connecting segment  206  of the plurality of connecting segments is disposed between the two conductive segments  202 . The connecting segment  206  disposed between the two conductive segments  202  aids in providing a continuous path for the flow of electric current. The connecting segment  206  is made of a flexible and conductive material. In one example, the conductive material includes a carbon fibre, conductive metals, and the like. In one embodiment, a combination of the one or more conductive segments  202  and the plurality of connecting segments  206  form the elongated lightning conducting path  110 . 
     In another embodiment, instead of the connecting segment, an airgap is provided between two conductive segments  202 . The airgap is narrow in width such that the airgap allows conduction of electrical current between the conductive segments  202 . Thus, a continuous path may be provided for any electrical current that may flow via the lightning conducting path  110 . 
     As noted hereinabove, the lightning conducting path  110  is disposed on an outer surface of the wind blade  101  along the trailing edge  102 . Hence, in the event of a fault in the lightning conducting path  110 , it can be easily accessed and repaired. In one embodiment, the faulty conductive segment  202  of the one or more conductive segments  202  may be replaced with a non-faulty, newer conductive segment  202 . 
     In one embodiment, the conductive segment  202  disposed at tip of the wind blade  101  acts as a toroid of the lightning protection subsystem. Although, the example of  FIG.  3    depicts conductive segments  202  coupled to the trailing edge  102 , the conductive segments may be coupled along other edges of the wind blade  101 . Further, in another example, the conductive segments may be a built-in structure along the trailing edge of the wind blade  101 . 
     Now referring to  FIG.  4   , a diagrammatical representation of one embodiment of a conductive segment  202  employed in the lightning protection subsystem of  FIG.  3    is disclosed. In the example of  FIG.  4   , the conductive segment  202  has a shape that defines shape of trailing edge of the wind blade  101 . Thus, a desired aerodynamic profile of the trailing edge of the wind blade is achieved. In one specific embodiment, the conductive segment  202  is a wedge-shaped structure, e.g. with a substantially triangular cross-section as shown in  FIGS.  3  and  4   . In another embodiment, the conductive segment may be coupled to the leading edge of the wind blade. In this embodiment, the conductive segment may have a shape such that the conductive segment does not hinder the airflow when coupled at the leading edge of the wind blade. 
     Further, in the example of  FIG.  4   , the conductive segment  202  includes a first attachment subunit  204  which extends outwards. Moreover, the conductive segment  202  includes a conductor  302  having an outer covering  304 . The outer covering  304  is an insulator. In one embodiment, the outer covering  304  may be a composite material. In the example of  FIG.  4    the conductive segment  202  includes a conductor  302  embedded in the outer covering  304 , such that the outer covering  304  entirely wraps around circumferential area of the conductor  302 . In another embodiment, the conductive segment  202  may include the outer covering disposed in such a manner that the outer covering partially wraps around the conductor. 
     As noted hereinabove, the lightning conducting path  110  includes one or more conductive segments  202 . The first dimensions of the conductive segments  202  of the lightning conducting path  110  may vary along the length of the edge, such as the trailing edge. The term ‘first dimensions,’ as used herein, refers to length, width, and height of the conductive segment. Reference numeral  306  represents a length of the conductive segment  202 . Reference numeral  308  represents width of the conductive segment  202 . Also, reference numeral  310  represents height of the conductive segment  202 . The length  306 , width  308 , and height  310  varies for different conductive segments  202 . Furthermore, in one example, the conductive segment  202  may have a tapering geometry along direction  312 . Although the example of  FIG.  4    depicts a wedge-shaped conductive segment  202 , other dimensions, sizes, and shapes of the conductive segments is anticipated. 
       FIG.  5    is a diagrammatical representation  400  of the trailing edge of the wind blade  101  of  FIG.  2   . The wind blade  101  includes a trailing edge  102  and a leading edge  104 . Specifically, the example of  FIG.  5   , represents the trailing edge  102  of the wind blade  101 . More specifically,  FIG.  5    depicts the trailing edge  102  which is adapted is such a manner that it is configured to snugly receive the conductive segments. 
     As represented herein, the trailing edge  102  has relatively flatter surface when compared to the trailing edge of a traditional wind turbine blade. In one embodiment, the trailing edge is relatively thicker and chord length is shorter to enable coupling of the conductive segment  202 . As clearly depicted in  FIG.  5   , the trailing edge  102  is designed to includes one or more receiving units  402 . In one example, the receiving unit may be a single slot along the length of the trailing edge  102  configured to receive multiple conductive segments  202 . In another example, a plurality of receiving units  402  may be formed along the length of the trailing edge  102 . 
     Further, second dimensions of the one or more receiving units complement the first dimensions of the conductive segments. In one example, the second dimensions of the receiving units  402  may vary based on the first dimension of the conductive segments  202 . Specifically, based on the first dimension of the conductive segments  202  that may be received at the receiving units  402 , the second dimensions of the receiving unit  402  may be determined. Based on the determined second dimensions of the receiving units  402 , the moulds may be prepared to create the desired dimension of the receiving units  402  along the trailing edge  102 . The term ‘second dimensions,’ as used herein, refers to dimensions of the receiving units. Specifically, the second dimensions of the receiving units may include a depth, length, and width of the receiving units. 
     Additionally, the receiving unit  402  includes one or more second attachment subunits  404 . The second attachment subunit  404  may include at least one of a slot, an aperture or a hole. The second attachment subunits  404  are configured to securely receive the first attachment subunits  204  of the conductive segments  202 . Accordingly, the conductive segments  202  are securely coupled to the trailing edge  102 . Once, all the receiving units  402  receive the respective conductive segments  202 , a desired aerodynamic profile of the trailing edge of wind blade  101  may be obtained. 
     The conductive segments  202  disposed in the receiving units  402  at tip end  408  of the wind blade  101  has comparatively reduced height, width, and length when compared to the height, width, and length of the conductive segments  202  disposed in the receiving units  402  at root end  406  of the wind blade  101 . Accordingly, the receiving units  402  at tip end  408  of the wind blade  101  has a relatively lesser depth, width, and length when compared to the depth, width, and length of the receiving units  402  at root end  406  of the wind blade  101 . 
       FIG.  6    is a diagrammatical representation  600  of at least a portion of the lightning protection subsystem disposed on a leading edge of the wind blade. In the example of  FIG.  6   , the lightning protection subsystem includes the lightning conducting path  111 . Further, the lightning conducting path  111  includes one or more conductive segments  604  disposed adjacent to one another. The one or more conductive segments  604  are couplable to the leading edge  104 . Specifically, the conductive segments  604  are received on receiving units  608  along the leading edge  104 . The receiving units  608  along the leading edge may include an even surface. Furthermore, the receiving units  608  may have a standard rounded shape similar to the leading edge shape of any standard wind turbine. 
     Once the conductive segments  604  are coupled to the leading edge  104  a desired aerodynamic profile of the leading edge of the wind blade  101  is achieved. More specifically, the conductive segments  604  are coupled to the leading edge  104  such that it does not hinder airflow along the leading edge  104 . In one embodiment, the conductive segments  604  may be coupled to the leading edge  104  of the wind blade  101  using adhesive, glue, double sided adhesive tapes, fasteners, clip-on mechanism, click mechanism, rail mechanism, and the like. 
     The conductive segments  604  may include a conductor having an outer covering of an insulator. In one example, the conductor includes a carbon fibre, other conductive metals, and the like. The conductive metals may include at least one of copper and aluminium. One or more conductive segments  604  form the elongated lightning conducting path  111 . Thus, a continuous path may be provided for any electrical current that may flow via the lightning conducting path  111 . 
     As noted hereinabove, the lightning conducting path  111  is disposed on outer surface of the wind blade  101  along the leading edge  104 . Hence, in the event of a fault in the lightning conducting path  111 , it can be easily accessed and repaired. In one embodiment, the faulty conductive segment  604  of the one or more conductive segments  604  may be replaced with a non-faulty conductive segment  604 . Accordingly, the lightning conducting path  111  may be repaired. 
       FIG.  7    is a diagrammatical representation  700  of one embodiment of a conductive segment employed in the lightning protection subsystem of  FIG.  6   . Specifically,  FIG.  7    depicts a conductive segment  604  disposed on the wind blade  101  when viewed in direction  606  (as shown in  FIG.  6   ). As represented in the example of  FIG.  7   , the conductive segment  604  is disposed on the leading edge  104  of the wind blade  101 . 
     The conductive segment  604  includes an outer covering  702  and a conductor  704 . The conductive segment  604 , specifically, the outer covering  702  includes a coupling portion  203 . In the example of  FIG.  7   , the coupling portion  203  includes clip-on elements  706 . In  FIG.  7   , the outer covering  702  is clipped on the leading edge  104  using clip-on elements  706 . Accordingly, the outer covering  702  is securely coupled to the leading edge  104  of the wind blade  101 . 
     In one embodiment, the outer covering  702  may be made of a single elongated piece such that a single outer covering  702  is configured to be coupled on the entire length of the leading edge  104 . In another embodiment, the outer covering  702  may be made of multiple segments, where the segments are disposed adjacent to one another to form a continuous covering along the length of the leading edge  104 . 
     The outer covering  702  may be made of an insulator. In one example, the outer covering includes composite. In one example, the composite may be the same material which is used to manufacture the wind blade shells. In another example, the outer covering  702  may be formed of a thermoplastic material. 
     In another embodiment, the outer covering  702  is prefabricated on the wind blade leading edge  104 . Geometry of the outer covering  702  is such that it provides a smooth surface. Specifically, the outer covering  702  allows smooth flow of air along the leading edge portion of the wind blade  101 . 
     In the example of  FIG.  7   , the conductor  704  is disposed on the leading edge  104  of the wind blade  101 . Specifically, the conductor  704  is disposed in a cavity  708  formed between the leading edge  104  and the outer covering  702 . In one example, the conductor  704  is a single piece elongated structure disposed along the length of the leading edge  104  and enclosed by the outer covering  702 . In the event of any fault in the conductor  704 , the outer covering  702  may be removed and the conductor  704  may be repaired/replaced. In another example, the conductor  704  is formed by several adjacent conductive segments, such as the conductive segment  202  of  FIG.  4   , for an easier replacement in case of a defect/damage. 
       FIGS.  8  and  9    are different diagrammatical representations  800 ,  900  of other embodiments of a conductive segment employed in the lightning protection subsystem of  FIG.  6   . The conductive segment includes an outer covering  802  and a conductor  804 . The conductor  804  is embedded in the outer covering  802 . The outer covering  802 , having the conductor  804 , is disposed along the leading edge  104  of the wind blade  101 . Specifically, the outer covering  802  is coupled along the leading edge  104  of the wind blade  101  via a coupling portion  203 . The coupling portion  203  includes clip on elements  806 . In another embodiment, the coupling portion  203  may include other fasteners, click mechanism, rail-based mechanism and the like. 
     In yet another embodiment, the coupling portion  203  may be a concave surface of the conductive segment  800 . The concave surface of the conductive segment  800  aids in securely coupling the conductive segment  800  on the leading edge  104  of the wind blade  101 . In such an embodiment, an adhesive, glue, and double-sided adhesive tapes may also be used for securely coupling the conductive segment  800  to the leading edge  104  of the wind blade  101 . Specifically, the outer covering  802  of the conductive segment  800  may be coupled to the leading edge  104  of the wind blade  101 . 
     Accordingly, the conductor  804  embedded in the outer covering  802  runs along the leading edge  104  of the wind blade  101  as clearly depicted in  FIG.  9   . In the example of  FIG.  9   , the conductor  804  may be a single piece elongated conductor. In another embodiment, the conductor  804  may be formed using multiple conductive segments. 
     The outer covering  802  with the embedded conductor  804  offers a smooth outer surface of the wind blade  101  to allow turbulence free flow of air. Accordingly, the outer covering  802  aids in providing an aerodynamic profile for the wind blade  101 . Further, in one embodiment, the outer covering  802 , with embedded conductor  804 , may be prefabricated along the leading edge  104  of the wind blade  101 . 
       FIG.  10    is a flow chart  950  representation of a method of manufacturing a wind blade having a lightning protection subsystem. At step  952 , at least a portion of a wind blade is moulded. Specifically, the wind blade  101  is manufactured in a mould in such a manner to form one or more receiving units along an edge of the wind blade. The edge includes a trailing edge, in one example. 
     In one embodiment, the receiving units have a determined depth, length, and width. The dimensions of the receiving units vary from the root portion to the tip portion of the wind blade. The dimensions of the receiving units along the trailing edge are determined prior to moulding. Accordingly, the moulds are prepared to manufacture a wind blade having desired dimension of receiving units. In another embodiment, the receiving units may be a seamless, smooth, and aerodynamic surface along the edge of the wind blade. 
     Additionally, at step  954 , one or more conductive segments are disposed along at least a portion of length of the edge of the wind blade. In one embodiment, the one or more conductive segments are disposed adjacent to one another along the length of the edge. Specifically, in one example, the conductive segments are securely positioned in the one or more receiving units along the trailing edge of the wind blade. Further, the conductive segments are coupled to the trailing edge of the wind blade. The one or more conductive segments form an elongated lightning conducting path of the lightning protection subsystem along length of the trailing edge. Accordingly, the lightning conducting path is easily accessible from the outer surface of the wind blade. In another embodiment, the conductive segments may be disposed along the length of the leading edge of the wind blade. 
     According to aspects of the present specification, a wind blade having a lightning protection subsystem and a method of manufacture of such a wind blade is disclosed. In accordance with aspects of the present specification, the one or more conductive segments are disposed along the trailing/leading edge of the wind blade. The combination of the conductive segments aids in forming a lightning conducting path of the wind blade. Since the lightning conducting path is disposed along the trailing/leading edge on outer surface of the wind blade and is formed using one or more conductive segments, it is relatively easier to repair any faults in the lightning conducting path. Although the proposed system and method has been described with respect to single piece wind blade, this system and method may also find application in modular blades, split blades, wind blades with pin joint, and the like. 
     While the invention has been described with reference to exemplary embodiments, it will be understood by those skilled in the art that various changes may be made, and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof.