DK201870496A1

DK201870496A1 - Temporary clamp assembly for repair and assembly of a sectional wind turbine blade and methods of using same

Info

Publication number: DK201870496A1
Application number: DKPA201870496A
Authority: DK
Inventors: Bech Anton
Original assignee: Vestas Wind Systems A/S
Priority date: 2018-07-20
Filing date: 2018-07-20
Publication date: 2019-07-18

Abstract

A temporary clamp assembly for a sectional wind turbine blade having a first blade section and a second blade section includes a first clamp support configured to be coupled to the first blade section, a second clamp support configured to be coupled to the second blade section, and a latch movably coupled to the first clamp support and movable between first and second positions. The latch is configured to be engaged with the second clamp support in the first position and disengaged from the second clamp support in the second position. A method of repairing a sectional wind turbine blade connected by a clamp assembly includes connecting a plurality of temporary clamp assemblies to the first and second blade sections, disconnecting the clamp assembly, supporting the second blade section with a hoisting system, and releasing the temporary clamp assemblies to disengage the blade sections. A method of assembling a sectional wind turbine blade using temporary clamp assemblies is also disclosed.

Description

TEMPORARY CLAMP ASSEMBLY FOR REPAIR AND ASSEMBLY OF A SECTIONAL WIND TURBINE BLADE AND METHODS OF USING SAME

Technical Field

The invention relates generally to wind turbines, and more particularly to a temporary clamp assembly that facilitates the repair and assembly of a sectional wind turbine rotor blade either up-tower or down-tower, and a method of repair and assembly of a sectional wind turbine rotor blade using such a temporary clamp assembly.

Background

Wind turbines are used to produce electrical energy using a renewable resource and without combusting a fossil fuel. Generally, a wind turbine converts kinetic energy from the wind into electrical power. A horizontal-axis wind turbine includes a tower, a nacelle located at the apex of the tower, and a rotor having a central hub and a plurality of blades coupled to the hub and extending outwardly therefrom. The rotor is supported on a shaft extending from the nacelle, which shaft is either directly or indirectly operatively coupled with a generator which is housed inside the nacelle. Consequently, as wind forces the blades to rotate, electrical energy is produced by the generator.

Traditional wind turbine blades include an outer shell positioned about an inner structural support. The outer shell typically includes upper and lower shell halves that mate together at corresponding edges to define an aerodynamic cross-sectional profile. The outer shell may be appropriately shaped so as to provide the aerodynamic aspects of the wind turbine blade. In a conventional process, the upper and lower shell halves are provided as one-piece structures which may be formed in a moulding process, for example. The inner structural support, which may include one or more spars, is typically positioned in a cavity between the upper and lower shell halves and extends in a longitudinal direction of the blade. The spar provides strength and stiffness to the blade such that the blades may withstand the loads imposed during operation of the wind turbine. The spar generally includes spar caps associated with the upper and lower shells and one or more spar webs that span between the spar

DK 2018 70496 A1 caps associated with the upper and lower shells. By way of example, the spar may include a box-shaped tubular element having spar caps engaged with the upper and lower shells and two spar webs extending therebetween. More recently, spar caps are being integrated into the formation of the upper and lower shells, such that the spar caps form part of the outer surface of the blades. One or more spar webs then extend between the integrated spar caps to provide structural support to the blade.

In recent years, wind power has become a more attractive alternative energy source and the number of wind turbines, wind farms, etc., has significantly increased, both on land and off-shore. Additionally, the size of wind turbines has also significantly increased, with modern wind turbine blades extending between 50 to 80 meters in length and is expected to further increase in the future. The increased length in the wind turbine blades has introduced a number of interesting considerations for wind turbine designers and manufacturers. For example, production facilities, including the physical space as well as the equipment for manufacturing the blades (e.g., moulds, cranes and other handling equipment) must accommodate the increased size of the blades. Additionally, the logistics and transportation of such large blades becomes increasingly difficult as the length of the blades continues to increase. In the end, the production, handling and transportation of large scale wind turbine blades is associated with significant challenges and high costs that may present a practical limit to the length of wind turbine blades which may be manufactured.

One approach for addressing these issues is to provide a wind turbine blade having two or more sections which are subsequently coupled together to form the complete wind turbine blade. In this approach, each blade section may include an outer shell and an inner spar. The blade sections are then brought together at a joint interface and secured together to form the complete blade. A typical design includes a plurality of connectors at the joint interface to provide a positive coupling between the blade sections. By way of example, a plurality of bolt/nut fasteners may be used to couple the blade sections together.

During operation of a wind turbine, a wind turbine blade may be damaged such that the wind turbine is taken out of operation and the damaged wind turbine blade repaired or replaced. In this regard, the damaged wind turbine blade may be disconnected

DK 2018 70496 A1 from the wind turbine at the rotor hub and removed from the wind turbine. The wind turbine blade will then be repaired down-tower or replaced. In order to remove a damaged wind turbine blade from the wind turbine, a large crane must be brought to the wind turbine site to effectuate the removal of the damaged blade. These largescale cranes are expensive to transport and operate. Accordingly, repair or replacement of a wind turbine blade is very expensive and drives up the costs associated with wind turbine operation.

Large scale cranes are also used during the initial assembly of the wind turbine, such as by hoisting a wind turbine blade up-tower for connection to the rotor hub. In addition, when the wind turbine includes sectional wind turbine blades, the crane may also be used to assemble the sectional blades. In this regard, a first blade section (e.g., a root blade section) may be in a fixed position on a support surface (e.g., ground, deck, quay, etc.) using, for example, one or more support frames. The crane is then used to lift and align a second blade section (e.g., tip blade section) relative to the first blade section. Once aligned, technicians will start securing fasteners to the sectional blade to secure the two blade sections together. This process of fastening the two sections together, however, can be a time-consuming process, during which the crane is holding the second blade section and cannot be used for other activities. As the cost of the crane is high, this process for assembling sectional wind turbine blades is also costly.

In view of the high costs of crane usage, a need exists for improved apparatus and methods for assembling, repairing, or replacing sectional wind turbine blades in a more efficient manner. More particularly, a need exists for apparatus and methods that use cranes and other hoisting equipment in a more efficient, cost-effective manner.

Summary

To these and other ends, aspects of the invention are directed to a temporary clamp assembly for use with a sectional wind turbine rotor blade having a first blade section and a second blade section configured to be coupled at a joint interface. The temporary clamp assembly includes a first clamp support configured to be coupled to the first blade section, a second clamp support configured to be coupled to the second

DK 2018 70496 A1 blade section, and a latch movably coupled to the first clamp support and movable between a first position and a second position. The latch is configured to be engaged with the second clamp support in the first position and is configured to be disengaged from the second clamp support in the second position. In one embodiment, a biasing mechanism is configured to bias the latch toward the first position. In this regard, the biasing mechanism may include a spring, wherein the spring is configured to be deflected as the latch moves away from the first position to generate a spring force. The temporary clamp assembly may further include a drive device. The drive device is configured to move the latch away from the first position and toward the second position under the action of the drive device. In this embodiment, the temporary clamp assembly further includes a remote controller for controlling the operation of the drive device. The remote controller may wirelessly communicate with the drive device. The first clamp support includes a first cross pin and the second clamp support includes a second cross pin. The latch may be pivotally coupled to the first clamp support and be carried thereby. The second clamp support includes a retention groove configured to facilitate the retention of the latch to the second clamp support. The second clamp support may also include an inclined surface, wherein the inclined surface is configured to cause movement of the latch away from the first position as the first and second blade sections are brought together at the joint interface.

In one embodiment, a wind turbine rotor blade includes a first blade section having a first blade interface, and a second blade section having a second blade interface, wherein the first blade interface engages with the second blade interface across a joint interface. A plurality of temporary clamp assemblies is coupled to the first and second blade sections across the joint interface. The plurality of temporary clamp assemblies provides the only connection between the first and second blade sections. In another embodiment, a wind turbine includes a tower, a nacelle coupled to the tower and a rotor coupled to the nacelle. The rotor includes at least one wind turbine rotor blade as described above.

Aspects of the invention are also directed to a method of repairing a sectional wind turbine blade having a first blade section and a second blade section connected together by a clamp assembly across a joint interface. The method includes connecting a plurality of temporary clamp assemblies to the first and second blade

DK 2018 70496 A1 sections, disconnecting the clamp assembly that holds the first and second blade sections together such that only the plurality of temporary clamp assemblies hold the first and second blade sections together, supporting the second blade section with a hoisting system, and releasing the plurality of temporary clamp assemblies so as to disengage the second blade section from the first blade section.

The method further includes disconnecting a portion of the clamp assembly prior to connecting the plurality of temporary clamp assemblies to the first and second blade sections and disconnecting a remaining portion of the clamp assembly after connecting the plurality of temporary clamp assemblies to the first and second blade sections. In one embodiment, the method includes connecting the plurality of temporary clamp assemblies to connecting elements made available through the disconnection of the portion of the clamp assembly. In one embodiment, supporting the second blade section may include supporting the second blade section with a ground-based hoisting system or a wind turbine-based hoisting system. Additionally, releasing the plurality of temporary clamp assemblies may further include remotely releasing the plurality of temporary clamp assemblies. In this regard, the plurality of temporary clamp assemblies each include a drive device, wherein remotely releasing the plurality of temporary clamp assemblies further includes remotely activating the drive devices to release the plurality of temporary clamp assemblies. Furthermore, in one embodiment, supporting the second blade section with the hoisting system occurs after the plurality of temporary clamp assemblies hold the first and second blade sections together.

In accordance with a further aspect of the invention, the method further includes providing a third blade section, supporting the third blade section with the hoisting system, positioning the third blade section adjacent the first blade section at the joint interface, engaging the plurality of temporary clamp assemblies such that only the plurality of temporary clamp assemblies hold the first and third blade sections together, connecting the clamp assembly that holds the first and third blade sections together, and disconnecting the plurality of temporary clamp assemblies. In one embodiment, engaging the plurality of temporary clamp assemblies further includes automatically engaging the plurality of temporary clamp assemblies as the first and third blade sections are brought together. The plurality of temporary clamp assemblies includes

DK 2018 70496 A1 a biasing mechanism having a spring. The method further includes deflecting the spring as the first and third blade sections are brought together to generate a spring force and releasing the spring force after the first and third blade sections engage each other at the joint interface to automatically engage the plurality of temporary clamp assemblies in a snap-fit manner. In one embodiment, connecting the clamp assembly that holds the first and third blade sections together further includes connecting a portion of the clamp assembly after engaging the plurality of temporary clamp assemblies. The method further includes connecting a remaining portion of the clamp assembly after disconnecting the plurality of temporary clamp assemblies. In one embodiment, the remaining portion of the clamp assembly may make use of connecting elements made available through the disconnection of the plurality of temporary clamp assemblies. In one embodiment, the third blade section may be released from the hoisting system upon the plurality of temporary clamp assemblies holding the first and third blade sections together.

In one embodiment, the method described above is directed to an up-tower repair wherein the wind turbine blade is attached to a hub of a wind turbine. In another embodiment, however, the repair is a down-tower repair wherein the wind turbine blade is removed from the wind turbine and positioned on a support surface, such as the ground, deck of a ship, etc., to conduct the repair.

In yet another embodiment, a method of assembling a sectional wind turbine blade having a first blade section and a second blade section includes supporting the first blade section in a fixed position, supporting the second blade section with a hoisting system, positioning the second blade section adjacent the first blade section at a joint interface, engaging a plurality of temporary clamp assemblies such that only the plurality of temporary clamp assemblies hold the first and second blade sections together, connecting a clamp assembly to hold the first and second blade sections together, and disconnecting the plurality of temporary clamp assemblies. In one embodiment, engaging the plurality of temporary clamp assemblies further includes automatically engaging the plurality of temporary clamp assemblies as the first and second blade sections are brought together. Connecting the clamp assembly that holds the first and second blade sections together may further include connecting a portion of the clamp assembly after engaging the plurality of temporary clamp

DK 2018 70496 A1 assemblies. In this embodiment, the method further includes connecting a remaining portion of the clamp assembly after disconnecting the plurality of temporary clamp assemblies. The second blade section may be released from the hoisting system upon the plurality of temporary clamp assemblies holding the first and second blade sections together.

Brief Description of the Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate one or more embodiments of the invention and, together with a general description of the invention given above, and the detailed description given below, serve to explain the invention.

Fig. 1 is a diagrammatic perspective view of a wind turbine in which embodiments of the invention may be used;

Fig. 2 is a perspective view of a sectional wind turbine blade;

Fig. 3 is a partial perspective view of a sectional wind turbine blade;

Fig. 3A is a cross-sectional view of the blade shown in Fig. 3;

Fig. 3B is another cross-sectional view of the blade shown in Fig. 3;

Fig. 4 is a perspective view of a clamp assembly for a sectional wind turbine blade;

Fig. 5 is a flow chart of a repair procedure in accordance with an embodiment of the invention;

Fig. 6 is a perspective view of a partially disassembled clamp assembly;

Fig. 7 is a perspective view of assembly of a temporary clamp assembly in accordance with an embodiment of the invention;

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Fig. 8 is another perspective view of assembly of a temporary clamp assembly in accordance with an embodiment of the invention;

Fig. 9 is an exploded disassembled view of a temporary clamp assembly in accordance with one embodiment of the invention;

Fig. 10 is a perspective view of disassembly of a remining portion of the clamp assembly;

Fig. 11 is a perspective view illustrating actuation of the temporary clamp assembly to disconnect blade sections of a wind turbine blade;

Fig. 12A is a perspective view of a hoisting system for handling a section of a wind turbine blade in accordance with an embodiment of the invention;

Fig. 12B is another perspective view of a hoisting system for handling a section of a wind turbine blade in accordance with an embodiment of the invention;

Figs. 13A-13D illustrate a snap-in feature of the temporary clamp assemblies;

Fig. 14 is a perspective view of another clamp assembly in accordance with one embodiment of the invention; and

Figs. 15A and 15B illustrate assembly of a sectional wind turbine blade in accordance with an embodiment of the invention.

Detailed Description

With reference to Fig. 1, a wind turbine 10 includes a tower 12, a nacelle 14 disposed at the apex of the tower 12, and a rotor 16 operatively coupled to a generator (not shown) housed inside the nacelle 14. In addition to the generator, the nacelle 14 houses miscellaneous components required for converting wind energy into electrical energy and various components needed to operate, control, and optimize the performance of the wind turbine 10. The tower 12 supports the load presented by the

DK 2018 70496 A1 nacelle 14, the rotor 16, and other components of the wind turbine 10 that are housed inside the nacelle 14 and also operates to elevate the nacelle 14 and rotor 16 to a height above ground level or sea level, as may be the case, at which faster moving air currents of lower turbulence are typically found.

The rotor 16 of the wind turbine 10, which is represented as a horizontal-axis wind turbine, serves as the prime mover for the electromechanical system. Wind exceeding a minimum level will activate the rotor 16 and cause rotation in a plane substantially perpendicular to the wind direction. The rotor 16 of wind turbine 10 includes a central hub 18 and at least one rotor blade 20 that projects outwardly from the central hub 18 at locations circumferentially distributed thereabout. In the representative embodiment, the rotor 16 includes three blades 20, but the number may vary. The blades 20 are configured to interact with the passing air flow to produce lift that causes the central hub 18 to spin about a central longitudinal axis.

The wind turbine 10 may be included among a collection of similar wind turbines belonging to a wind farm or wind park that serves as a power generating plant connected by transmission lines with a power grid, such as a three-phase alternating current (AC) power grid. The power grid generally consists of a network of power stations, transmission circuits, and substations coupled by a network of transmission lines that transmit the power to loads in the form of end users and other customers of electrical utilities. Under normal circumstances, the electrical power is supplied from the generator to the power grid as known to a person having ordinary skill in the art.

Figs. 2 and 3 illustrate an exemplary sectional wind turbine blade 20. The wind turbine blade 20 includes a first blade section 22 and a second blade section 24 which are connected to each other at a joint interface 26 to form an assembled blade 20. In an exemplary embodiment, the joint interface 26 may be located at approximately the mid-span of the wind turbine blade 20; however, other positions for a joint interface along the span of the blade 20 are also possible. The first blade section 22 includes a root end 28, a leading edge 30a, a trailing edge 32a, a suction side 34a and a pressure side 36a. The first blade section 22 terminates at a first blade interface 38 opposite to the root end 28. Similarly, the second blade section 24 includes a tip end 40, a leading edge 30b, a trailing edge 32b, a suction side 34b and a pressure side

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36b. The second blade section 24 begins at a second blade interface 42 opposite to the tip end 40. The first blade interface 38 and the second blade interface 42 may be brought together to form the joint interface 26.

Fig. 3A illustrates a cross section of the blade 20 in accordance with one embodiment of the invention (wherein the webs have been removed for clarity purposes) through the first blade section 22. As illustrated in this figure, the first blade section 22 includes spar caps 50a, 52a associated with an upper shell half that defines the suction side 34a and a lower shell half that defines the pressure side 36a of the blade 20, respectively. Additionally, the blade 20 may include additional support elements adjacent the trailing edge 32 in the form of trailing edge stringers 54a, 56a also associated with the shell halves that define the suction and pressure sides 34a, 36a of the blade 20. Fig. 3B shows a similar cross section through the second blade section 24, which includes spar caps 50b, 52b and trailing edge stringers 54b, 56b associated with the upper and lower shell halves that define the suction and pressure sides 34b, 36b of the blade 20. In one embodiment, the spar caps 50, 52 and trailing edge stringers 54, 56 may be incorporated into the blade so as to form part of the outer shell of the blade sections 22, 24. In an alternative embodiment, the spar caps and possibly the training edge stringers do not form part of the outer shell of the blade sections, but engage with an interior surface of the outer shell.

Figs. 3 and 4 illustrate exemplary clamp assemblies 60 for securing the first and second blade sections 22, 24 together across the joint interface 26. The clamp assembly 60 includes a plurality of clamp supports, which may take the form of a plurality of cross pins 62, a plurality of retention heads 64, and a plurality of fasteners 66. The clamp assembly 60 cooperates with a plurality of connecting elements 68 having eyes 70 provided with the blade sections 22, 24 adjacent the blade interfaces 38, 42 to securely couple the blade sections 22, 24 together across the joint interface 26 to thereby form the assembled blade 20. Additional details of clamp assembly 60, as well as alternative clamp assemblies in accordance with aspects of the invention, may be provided in commonly-owned International Application Nos. PCT/DK2017/050441 and Danish Patent Application No. 2018 70299, each being incorporated by reference herein. Accordingly, a further description of clamp assembly 60 will not be provided herein. It is noted, however, that the connection joint

DK 2018 70496 A1 at the joint interface 26 includes a plurality of clamp supports, retention heads, and fasteners that are manually assembled by one or more technicians during assembly of the sectional wind turbine blade 20.

As noted above, in some instances, wind turbine blades may become damaged during operation, and the entire wind turbine blade may have to be removed from the wind turbine to effectuate a repair or replacement. It has been noted, however, that much of the damage to wind turbine blades occurs to the outer portion of the wind turbine blade, for example, from the mid span section to the tip. The inner portion of the wind turbine blade is often undamaged and capable of further operation. For example, lightning strikes and strikes with foreign objects typically damage a blade adjacent its tip. In any event, replacing the entire wind turbine blade to address damage along the outer portion of the blade is costly and inefficient. Ideally, wind turbine manufacturers would like to replace only the portion of the wind turbine blade that has been damaged and maintain the undamaged portion of the blade. Sectional wind turbine blades not only offer certain advantages in manufacturing and transportation, but also provide the opportunity to replace only an outer portion of a wind turbine blade that has been damaged while maintaining an inner portion of a wind turbine blade that remains operationally viable. Aspects of the present invention take advantage of the modular feature of sectional wind turbine blades to effectuate a repair/replacement procedure.

In this regard, one aspect of the present invention provides a sectional wind turbine blade having a first (inner) blade section 22 and a second (outer) blade section 24 coupled together at a joint interface 26. The second blade section 24 has sustained some type of damage such that repair or replacement of the second blade section 24 is desired. As used herein, the term repair procedure encompasses both a repair and a replacement of a wind turbine blade portion. In this regard, and in an exemplary wind turbine blade repair procedure, the two blade sections 22, 24 are disconnected at the joint interface 26 and the second blade section 24 removed. In one embodiment, the second blade section 24 may be moved to a location, either at the wind turbine site or remote from the wind turbine site, where a repair is implemented in order to fix the damaged aspects of the existing blade 20. The repaired second blade section 24a may then be moved back to the location of the first blade section 22 and the two blade sections 22, 24 coupled together again. In an alternative embodiment, after the

DK 2018 70496 A1 second blade section 24 is removed from the first blade section 22, a new or refurbished blade section 24a may be moved into position and connected to the first blade section 22. In an exemplary embodiment, the repair procedure described above may be implemented up-tower, i.e., while the wind turbine blade 20 is attached to the wind turbine 10. In an alternative embodiment, the repair procedure may be implemented down-tower, i.e., while the wind turbine blade 20 is removed from the wind turbine 10.

Fig. 5 provides a flow chart outlining the steps for effectuating an up-tower repair procedure for a wind turbine blade 20 having a damaged outer portion of the blade 20 in accordance with one embodiment of the invention. In a first step 72 of the repair procedure and as illustrated in Fig. 1, for example, after the wind turbine 10 is taken out of operation the damaged wind turbine blade 20 may be positioned in a downward direction (e.g., generally parallel to the tower 12) and the rotor 16 locked against further rotation. Rotor locks are generally well known in the industry and will not be described further herein. A technician located at the rotor hub 18 will then be lowered downwardly along the blade 20 from the rotor hub 18 and be positioned at the joint interface 26 between the first blade section 22 (e.g., the root blade section) and the second blade section 24 (e.g., the tip blade section). In this regard, a winch system may be operatively coupled to a basket or platform and be used to lower the technician downwardly along the blade 20. In one embodiment, the technician may be lowered downwardly along an exterior of the blade 20. In an alternative embodiment, the technician may be lowered downwardly along an interior of the blade 20. In any event and in a next step 74, when the technician has been lowered to the joint interface 26 of the sectional blade 20, the technician may disassemble a portion of the clamp assembly 60 holding the two blade sections 22, 24 together. In this step, however, only a relatively small portion of the clamp assembly 60 may be disassembled such that the integrity of the connection joint between the blade sections 22, 24 is not jeopardized. In other words, the remaining portion of the clamp assembly 60 is more than sufficient to maintain the connection between the two blade sections 22, 24 when in this standstill configuration.

Fig. 6 illustrates the disassembly of a portion of the clamp assembly 60 in accordance with one embodiment of the invention. In this regard, the fasteners 66 may include a

DK 2018 70496 A1 plurality of stud bolts 76 and nuts 78 which extend across the joint interface 26 and engage with the retention heads 64 on either side of the joint interface 26. In this embodiment, the retention heads 64 may have a modular arrangement and be formed from a plurality of bridge elements 80. The technician may loosen the nuts 78 and remove the stud bolts 76, bridge elements 80 and cross pins 62 associated with the stud bolts 76.

In a subsequent step 82 of the repair procedure, the technician may install several temporary clamp assemblies 84 at the joint interface 26 for temporarily connecting the blade sections 22, 24 together. This step is illustrated, for example, in Figs. 7 and 8. Fig. 9 illustrates an exemplary embodiment of a temporary clamp assembly 84 and includes a pair of clamp supports configured as cross pins 86, 88 and a fastener configured as a movable latch 90. The cross pins 86, 88 are sized similar to the cross pins 62 so as to fit within the eyes 70 of the connecting elements 68 in a similar manner. The cross pins 86, 88, however, are not identical, for purposes that will be explained more fully below. Cross pin 86 includes a body having generally planar upper and lower surfaces 94, 96, generally planar first and second side surfaces 98, 100, a generally arcuate inner end surface 102, and a generally planar outer end surface 104. The inner end surface 102 may be shaped (e.g., curved) to generally correspond to the curvature of the arcuate end of the eyes 70 of the connecting elements 68, and thereby distribute loads in an efficient manner. The upper surface 94 includes a raised boss 106 that extends above the connecting elements 68 when the cross pin 86 is coupled to a blade section (Figs. 7 and 8). Cross pin 88 includes a body having generally planar upper and lower surfaces 108, 110, generally planar first and second side surfaces 112, 114, a generally arcuate inner end surface 116, and a generally planar outer end surface 118. The inner end surface 116 may be shaped to generally correspond to the curvature of the arcuate end of the eyes 70 of the connecting elements 68, similar to the above. For reasons that will become clear below, the upper surface 108 of cross pin 88 has an inclined configuration such that the outer end surface 108 extends further than the inner end surface 116 (e.g., further above the connecting element 68). The outer end surface 118 includes a groove 120 adjacent to the upper surface 108.

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In this exemplary embodiment, the moveable latch 90 is movably attached to cross pin 86. More particularly, latch 90 is rotatably (e.g., pivotably) coupled to the raised boss 106 of the cross pin 86. In this regard, the latch 90 includes a drive shaft 122 that extends through a bore in the cross pin 86 to define end portions outboard of the raised boss 106. The latch further includes a U-shaped pawl 124 having a pair of generally parallel legs 126 and a cross leg 128 at one end of the legs 126. The opposed ends of the legs 126 include generally circular hubs 130 secured to the drive shaft 122 such that the pawl 124 rotates with rotation of the drive shaft 122. To this end, the latch 90 may include a drive device 132 (shown schematically in Figs. 7 and 8), such as a motor or suitable actuator, for controllably providing the rotation of the drive shaft 122. In one embodiment, the drive device 132 includes a clutch or other release device that selectively allows the pawl 124 to be driven by the drive device (e.g., through rotation of the drive shaft 122) in one or both rotational directions or allows the pawl 124 to rotate relative to the drive shaft 122 in one or both rotational directions. In this regard, the drive shaft 122 and the hubs 130 of the pawl 124 may have drive wheels (e.g., gears, cogs, etc.) that provide a drive mode and a slip mode of operation. The reasons for allowing slippage will become clear below.

The pawl 124 of the latch 90 is movable between a first position and a second position. From the perspective of Figs. 7 and 8, when the latch 90 is in the first position (e.g., a down position), the pawl 124 is positioned to engage the cross pin 88 across the joint interface 26 when the blade sections 22, 24 are brought together (Fig. 8), and when the latch 90 is in the second position (e.g., an up position), the pawl 124 is configured so as to not engage with the cross pin 88 across the joint interface 26 (Fig. 7) when the blade sections 22, 24 are brought together. In an exemplary embodiment, the latch 90 may include a biasing mechanism 134 for biasing the pawl 124 toward the first down position. In this regard, the biasing mechanism 134 includes a bridge 136 extending between the generally parallel legs 126 of the pawl 124. The bridge 136 includes an opening or slot which receives a tension screw 138 having a threaded shaft and a head. A linear spring 140 is captured between the head of the tension screw 138 and an upper surface of the bridge 136. The threaded end of the shaft of the tension screw 138 is received in a threaded bore in the upper surface 94 of the cross pin 86. The bridge 136 may not be fixedly coupled to the legs 126, but float between the legs 126 and the head of the tension screw 138. In this way, as the pawl

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124 is moved away from the first position toward the second position, the spring 140 becomes compressed and creates a biasing force on the pawl 124 in a direction back toward the first position.

To install the temporary clamp assembly 84 at the joint interface 26, the technician will insert the cross pin 86 in one of the available eyes 70 of a connecting element 68 in one of the blade sections 22, 24. If the technician is positioned external of the wind turbine blade 20, then the latch 90 will generally face the exterior of the blade 20. If the technician is positioned internal of the wind turbine blade 20, then the latch will generally face the interior of the blade 20. In an exemplary embodiment, the cross pin 86 is positioned in the first blade section 22 which remains attached to the wind turbine 10. Alternatively, the cross pin 86 may be positioned in the second blade section 24 (not shown). The technician then inserts the cross pin 88 in the aligned eye 70 of the connecting element 68 on the other blade section 24 across the joint interface 26. The cross pins 86, 88 may include stop pins 142 (Fig. 7) or other stop mechanisms that provide an indication of proper seating of the cross pins 86, 88 in the blade sections 22, 24 and prevent the cross pins 86, 88 from sliding through the eyes 70 of the connecting elements 68. Lastly, the pawl 124 may be placed or allowed to move (e.g., under the force from the drive device 132 or biasing mechanism 134) to the first position such that the temporary clamp assembly 84 is fully engaged and connects the first and second blade sections 22, 24 (Fig. 8). In an exemplary embodiment, the technician may install anywhere between two to seven temporary clamping mechanisms 84 between the two blade sections 22, 24. In one embodiment, for example, one temporary clamp assembly 84 may be positioned in each of the spar caps 50, 52, and one temporary clamp assembly 84 may be positioned in one of the trailing edge stringers 54, 56 (e.g., thus a total of three temporary clamp assemblies may be connected across the joint interface 26). Other numbers and arrangements of the temporary clamp assemblies 84 are also possible, depending on various factors including size of the blade, standstill wind conditions, etc.

In a next step 144, the technician may disassemble the remaining portion of the clamp assembly 60. Similar to the above and as illustrated in Fig. 10, the technician may loosen the nuts 78 and remove the stud bolts 76, bridge elements 80 and cross pins 62 associated with the remaining stud bolts 76. After this disassembly step, the only

DK 2018 70496 A1 elements maintaining the connection between the two blade sections 22, 24 are the temporary clamp assemblies 84, of which there are relatively few. At this point in the repair procedure, the technician may move away from the joint interface 26 and away from the wind turbine blade 20 at the rotor hub 18.

Also, at this point in the repair procedure and in a next step 146, the second blade section 24 may be operatively coupled to a hoisting system 148 configured to support the second blade section 24 upon being separated from the first blade section 22 and for moving the second blade section 24 away from the joint interface 26. In one embodiment, as illustrated in Fig. 12A, the hoisting system 148 may be a ground crane 148a. In an alternative embodiment, however, the hoisting system 148 may be a hoisting arrangement associated with the wind turbine 10 itself, such as the internal wind turbine crane in the nacelle 14 (not shown) or a winch system 148b associated with the hub 18, as illustrated, for example, in Fig. 12B. In any event, the hoisting system 148 typically includes a hoisting cable 150 that couples to the second blade section 24. In this regard, various attachment mechanisms, such as various blade slings and gripping devices, may be coupled to the hoisting cable 150 for interfacing with the second blade section 24. Such attachment mechanisms are generally known in the art and thus will not be discussed further herein. In addition to the hoisting cable 150, one or more guide cables 152 may be attached near the tip end 40 of the second blade section 24. One or more technicians on the ground, for example, may use the guide cables 152 to manipulate the blade during its movement with the hoisting system 148.

Once the hoisting system 148 is in place to support the second blade section 24, in a next step 153 of the repair procedure, the temporary clamp assemblies 84 may be disengaged such that the second blade section 24 is free of the first blade section 22 and is being supported by the hoisting system 48, which may be used to lower the second blade section 24 to the ground, deck of a ship, etc. This step is illustrated in Fig. 11. In this regard, it may be undesirable to have personnel around the joint interface 26 and wind turbine blade 10 as the second blade section 24 is being separated from the first blade section 22. Accordingly, and in one aspect of the invention, the temporary clamp assemblies 84 may be disengaged in a manner that does not require technicians near the joint interface 26.

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In this regard, the drive device 132 may include an internal drive controller 154 configured to control the operation of the drive device 132. The drive controller 154 may be configured to communicate with a remote controller 156 such that the drive device 132 may be controlled from a remote location. In an exemplary embodiment, the remote controller 156 may be configured to wirelessly communicate with the drive controller 154 of the drive device 132. Other forms of communication between the two controllers 154, 156, however, may also be possible. Such drive controllers 154 and remote controllers 156 are generally known in the art and will not be described further herein. The remote controller 156 may be positioned in a host of locations, such as in the cab of the ground crane 148a or in the rotor hub 18 or nacelle 14. The remote controller 156 may also be positioned at various locations on the ground, deck, platform, etc. In any event, a technician may trigger the remote controller 156 so as to active the drive device 132 and actively drive the pawls 124 from their first position (e.g., their closed or engaged positions) to their second position (e.g., their opened or disengaged positions), thereby disengaging the pawls 124 from the cross pins 88 and releasing the second blade section 24 from its engagement with the first blade section 22. Once the pawls 124 are free of the cross pins 88, the hoisting system 148 may move the second blade section 24 away from the joint interface 26 and to the ground, deck, etc. (Figs. 12A and 12B). The remote controller 156 may also be activated to release the drive device 132 such that the biasing mechanism 134 moves the pawls 124 back to their first positions. Once on the ground, deck, etc., a technician may remove the cross pins 88 from the eyes 70 of the connecting elements 68 at the blade interface 42 of the second blade section 24.

In a further step 158 of the repair procedure, a repaired, refurbished, or new blade section, referred to herein as a third blade section 24a, may be provided at the site of the wind turbine 10 which is substantially similar to the second blade section 24 removed from the wind turbine 10. A technician on the ground, deck, etc., may position cross pins 88 in the eyes 70 of the connecting elements 68 of the third blade section 24a corresponding to the location of the cross pins 86 and latches 90 on the first blade section 22 that remains attached to the rotor hub 18 of the wind turbine 10. Guide cables 152 may also be attached near the tip end 40 of the third blade section 24a. The attachment mechanism at the end of the hoisting cable 150 may be attached to

DK 2018 70496 A1 the third blade section 24a and the hoisting system 148 activated to lift the third blade section 24a toward the joint interface 26.

During the lift of the third blade section 24a, the guide cables 152 may be manipulated by technicians on the ground, deck, etc. so as to align the two blade sections 22, 24a. With the two blade sections 22, 24a generally aligned relative to each other and the pawls 124 of the latches 90 in their first position, the hoisting system 148 may execute one final lift which causes the temporary clamp assemblies 84 to automatically engage such that the first and third blade sections 22, 24a are sufficiently secured together at the joint interface 26. Similar to the above, it may be undesirable to have personnel around the joint interface 26 and wind turbine blade 10 as the third blade section 24a is being attached to the first blade section 22. Accordingly, and in one aspect of the invention, the temporary clamp assemblies 84 are configured to be engaged in a manner that does not require technicians near the joint interface 26. This may be achieved, for example, by providing the temporary clamp assemblies 84 with a snapfit feature.

Figs. 13A-13D illustrate the snap-fit feature that allows automatic engagement of the temporary clamp assemblies 84 as the two blade sections 22, 24a are brought together. In this regard, and as noted above, the pawls 124 of the latches 90 disposed adjacent the blade interface 38 of the first blade section 22 are in their first positions. In this position, the ends of the pawls 126 extend beyond the blade interface 38 of the first blade section 22 (Fig. 13A). As the third blade section 24a approaches the first blade section 22, and with the blade interface 42 confronting the blade interface 38, the ends of the pawls 124 engage with the inclined upper surface 108 of the cross pins 88. As the two blade sections 22, 24a are brought closer together, the ends of the pawls 124 ride up the inclined surface 108 (operating as a cam surface) causing a deflection of the pawls 126 away from the first closed position and toward the second opened position (Fig. 13B). This deflection compresses the spring 140 of the biasing mechanism 134 creating or increasing the biasing force urging the pawls 124 back toward the first closed position. When the two blade sections 22, 24a come together such that the blade interfaces 38, 42 engage each other (Fig. 13C), the biasing force caused by the deflection of the pawls 124 and compression of the springs 140 is sufficient to cause to pawls 124 to move over the apex 160 of the cross pin 88 and be

DK 2018 70496 A1 seated in the groove 120 of the cross pin 88 adjacent the apex 160 (Fig. 13D). Because of this snap-fit feature, it is unnecessary for a technician to be at the joint interface 26 when the third blade section 24a is attached to the first blade section 22. The temporary clamp assemblies 84 are configured to support the connection between the first and third blade sections 22, 24a, and the hoisting device 148 may be disengaged from the third blade section 24a such that the connection joint is being supported only by the temporary clamp assemblies 84.

In a following step 162 of the repair procedure, the technician will then be lowered back down along the interior of the blade 20 (i.e., either along the exterior or the interior of the blade) and be positioned at the joint connection 26 between the first blade section 22 and the third blade section 24a. At this point, the technician will assemble a portion of the clamp assembly 60. In this regard, the technician will insert the cross pins 62 into the eyes 70 of the connecting elements 68, assemble the retention heads 64 from the bridge elements 80, insert the stud bolts 76 through the retention heads 64, and secure the nuts thereto to couple the blade sections 22, 24a together. These steps are essentially the reverse steps of that illustrated in Fig. 10. The assembled portion of the clamp assembly 60 is configured to fully support the connection between the first and third blade sections 22, 24a even in the absence of the temporary clamp assemblies 84 during standstill conditions. Accordingly, and in a next step 164, the temporary clamp assemblies 84 may be disassembled and removed from the joint interface 26. These steps are essentially the reverse steps of that illustrated in Figs. 7 and 8. In this regard, a technician may engage the remote controller 156 to activate the drive device 132 to disengage the pawls 124 from the cross pins 88. Alternatively, the disengagement of the pawls 124 from the cross pins 88 may also be done manually. In any event, once the pawls 124 are disengaged from the cross pins 88, the cross pins 88 may then be removed from their respective connecting elements 68 in the third blade section 24a. The technician may then release the biasing mechanism 134, such as by disengaging the tension screw 138 from the threaded bore in the upper surface 94 of the cross pin 86. The cross pins 86 and latches 90 may then be removed from their respective connecting elements 68 in the first blade section 22.

In another step 166 of the repair procedure, the remaining portion of the clamp assembly 60 may be assembled to complete the connection between the first and third

DK 2018 70496 A1 blade sections 22, 24a via the clamp assembly 60. Of course, similar to the above, the technician will insert the cross pins 62 into the eyes 70 of the connecting elements 68, assemble the retention heads 64 from the bridge elements 80, insert the stud bolts 76 through the retention heads 64, and secure the nuts 78 thereto to couple the blade sections 22, 24a together. These steps are essentially the reverse steps of that illustrated in Fig. 6. In a final step 168, the technician may then move away from the joint interface 26 and away from the wind turbine blade 20. If other blades 20 of the wind turbine 10 have been damaged, then the process described above may be repeated. In any event, after all the blades 20 have been repaired, the wind turbine 10 may be placed back in operation.

The up-tower repair procedure described above provides a number of advantages to wind turbine operators and manufacturers. First, and as mentioned above, a considerable amount of the damage to wind turbine blades occurs in the outer portion of the blades. As many wind turbine blades today are sectional blades, repair processes can make use of their modular design to limit the amount of the blade that needs to be repaired. However, there needs to be various apparatus and methods that as a practical matter allow only an outer portion of a wind turbine blade to be repaired (e.g., replaced) in a cost-effective manner. Aspects of the present invention provide such apparatus and methods for a cost effective up-tower repair procedure that takes advantage of the modular design of many modern wind turbine blades. The cost savings come in the form of potentially replacing only a portion of a damaged blade instead of replacing the entire blade. The material costs alone may be quite significant. However, because the replacement portions are smaller, the associated transportation costs may also be reduced. Moreover, because the replacement portions are smaller in size compared to an entire blade, the size of the equipment used to effectuate the replacement, for example, may also be smaller. In the inventive repair procedure described above, the large ground cranes used during initial assembly are not required for effectuating a repair. In this regard, because the portion of the blade being replaced is smaller, a smaller crane may be used during the procedure. Additionally, crane rental and operation are expensive and efficient usage of a crane is desirable. Aspects of the present invention provide for efficient use of a crane. For example, in the normal course, the crane might be used to support the blade during the entire time of the repair procedure. This may be a considerable period

DK 2018 70496 A1 of time. According to aspects of the present invention, however, much of the assembly and disassembly of the clamp assemblies that hold the blade sections together at the joint interface are done without a crane. According to the inventive method, the crane is limited in its use to when it is necessary to support the blade section with something other than an adjacent blade section. Thus, it is believed that the amount of crane time is significantly reduced in the inventive method as compared to more conventional approaches, which will further reduce the costs of the repair procedure.

While the temporary clamp assembly and method of using the temporary clamp assembly was described above relative to a particular clamp assembly 60 having cross pins 62, retention heads 64 formed from a plurality of bridge elements 80, and fasteners 66, it is contemplated that the aspects of the present invention may be used with a host of clamp assembly designs used to couple adjacent sections of a sectional wind turbine blade. Accordingly, the present invention is not limited to the particular clamp assembly shown and described herein. For example, other clamp assemblies disclosed in commonly-owned International Application Nos. PCT/DK2017/050441 and Danish Patent Application No. 2018 70299 may be used in accordance with aspects of the invention. Those of ordinary skill in the art will understand how to adapt the present invention to the particular clamp assembly used to secure the sectional wind turbine blade together.

Fig. 14 illustrates another alternative embodiment of a temporary clamp assembly 84a, in which like reference numbers refer to like features illustrated in the prior figures. The temporary clamp assembly 84a is similar to temporary clamp assembly 84 but for the biasing mechanism 136a that generates the force that urges the pawl 124 toward the first position (shown in Fig. 14). In this embodiment, a torsional spring 140a may be used to generate the biasing force. In this regard, the spring 140a includes a portion coupled to the legs 126 and a portion disposed about the drive shaft 122. When the pawl 124 is rotated away from the first position, such as under the action of the drive device 132, the spring is torsionally compressed so as to generate the biasing force urging the pawl 124 back toward the first position in much that same way as spring 140.

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While aspects of the present invention were described as part of an up-tower repair procedure, the invention is not so limited. In this regard, aspects of the present invention may be used during the initial assembly of the sectional wind turbine blade, e.g., such as during initial installation of the wind turbine. As understood, sectional wind turbine blades are typically transported in sections. When the sectional blades arrive at the installation site, the blades must be assembled to form the complete blade. To this end, the first blade section may be fixed in position, such as by using one or more frames. Subsequently, a crane is used to lift and align the second blade section with the first blade section. This crane is often the large crane used to assemble the wind turbine. One or more technicians then assemble some type of clamp assembly for securing the blade sections together. This step is typically manually done and takes considerable time. In the normal course, the crane is used to support the second blade section during the assembly of the clamp assembly and is therefore prohibited from being used in a more efficient manner during this time.

To reduce crane time and improve the use of the crane in a more efficient manner, the initial assembly of a sectional wind turbine blade 20 may use aspects of the present invention. To this end, Figs. 15A and 15B illustrate the initial assembly of a sectional wind turbine blade 20 in accordance with an embodiment of the invention. Similar to current practice, the first wind turbine section 22 may be fixed in position by supporting the blade section 22 with one or more frames 178. A crane or other hoisting system may be used to move and align the second blade section 24 with the first blade section 22. However, unlike conventional approaches, the temporary clamp assemblies 84 may be used to temporarily connect the second blade section 24 to the first blade section 22 such that the temporary clamp assemblies 84 support the second blade section 24 without the need of the crane or other large hoisting system. In this way, the hoisting system may be utilized in other, perhaps more productive activities.

In this regard, either before or after placing the first blade section 22 in frames 174, a technician may couple a plurality of cross pin 86/latch 90 assemblies to the first blade section 22 adjacent the first blade interface 38. The latches 90 may be positioned in their first position. This may be done, for example, in the manner more fully described above in relation to the connecting elements 68. Additionally, before or after the second blade section 24 is lifted by the crane, the technician may couple a plurality of

DK 2018 70496 A1 cross pins 88 in corresponding locations on the second blade section 24 adjacent the second blade interface 42. Once these elements of the temporary clamp assemblies 84 are in place, the crane may move the blade sections 22, 24 together. When the blade interfaces 38, 42 engage with each other, the temporary clamp assemblies 84 automatically engage such that the first and second blade sections 22, 24 are sufficiently secured together at the joint interface 26. With relatively few temporary clamp assemblies 84 (e.g., between two to seven temporary clamp assemblies) the second blade section 24 may be supported by the first blade section 22. Accordingly, the hoisting system may be disengaged from the second blade section 24. In one embodiment, the second blade section 24 may be cantilevered off of the first blade section 22. In an alternative embodiment, however, a frame (not shown) may be located near the tip 40 to provide additional support for the second blade section 24.

In any event, at this point, a technician may then begin to assemble the clamp assembly 60, such as in the manner described above in reference to step 162. After this step, the temporary clamp assemblies 84 may be disassembled similar to that described above in reference to step 164 and the remaining portion of the clamp assembly 60 assembled, similar to that described above in reference to step 166. With the completion of this step, the wind turbine blade 20 is essentially assembled and ready to be coupled to the hub 18 of the wind turbine 10. Fig. 15A illustrates an assembly procedure when the chord of the wind turbine blade 20 is generally in a vertical direction and Fig. 15B illustrates an assembly procedure when the chord of the wind turbine blade 20 is generally in a horizontal direction.

While the repair procedure discussed above was directed to an up-tower repair of a wind turbine blade, in some instances, it may be desirable to conduct the repair procedure down-tower by removing the entire wind turbine blade 20 from the wind turbine 10. Even in this instance, aspects of the present invention may be used to provide certain benefits, such as more efficient usage of the crane or other hoisting system. In this embodiment, the damaged wind turbine blade 20 may be removed from the wind turbine 10 and placed on one or more frames 178 on the ground, deck, etc. Once the wind turbine blade 20 is located in the frames 178, the repair procedure described above starting with step 74 (Fig. 5) may be implemented using the

DK 2018 70496 A1 temporary clamp assemblies 78. Thus, aspects of the invention may be used in a wide variety of applications to provide certain advantages and benefits.

While the present invention has been illustrated by a description of various preferred embodiments and while these embodiments have been described in some detail, it is not the intention of the Applicant to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art. Thus, the various features of the invention may be used alone or in any combination depending on the needs and preferences of the user.

Claims

Claims

1. A temporary clamp assembly (84) for use with a sectional wind turbine rotor blade (20) having a first blade section (22) and a second blade section (24) configured to be coupled at a joint interface (26), the temporary clamp assembly (84) comprising:

a first clamp support (86) configured to be coupled to the first blade section (22);

a second clamp support (88) configured to be coupled to the second blade section (24); and a latch (90) movably coupled to the first clamp support (86) and movable between a first position and a second position, wherein the latch (90) is configured to be engaged with the second clamp support (88) in the first position and is configured to be disengaged from the second clamp support (88) in the second position.
2. The temporary clamp assembly of claim 1, further comprising a biasing mechanism (134) configured to bias the latch (90) toward the first position.
3. The temporary clamp assembly of claim 2, wherein the biasing mechanism (134) includes a spring (140, 140a), wherein the spring is configured to be deflected as the latch (90) moves away from the first position to generate a spring force.
4. The temporary clamp assembly of any of the preceding claims, further comprising a drive device (132), the drive device configured to move the latch (90) away from the first position and toward the second position under the action of the drive device (132).
5. The temporary clamp assembly of claim 4, further comprising a remote controller (156) for controlling the operation of the drive device (132).
6. The temporary clamp assembly of claim 5, wherein the remote controller (156) wirelessly communicates with the drive device (132).

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7. The temporary clamp assembly of any of the preceding claims, wherein the first clamp support includes a first cross pin (86) and the second clamp support includes a second cross pin (88).
8. The temporary clamp assembly of any of the preceding claims, wherein the latch (90) is pivotally coupled to the first clamp support (86).
9. The temporary clamp assembly of any of the preceding claims, wherein the second clamp support (88) includes a retention groove (120) configured to facilitate the retention of the latch (90) to the second clamp support (88).
10. The temporary clamp assembly of any of the preceding claims, wherein the second clamp support (88) includes an inclined surface (108), the inclined surface configured to cause movement of the latch (90) away from the first position as the first and second blade sections (22, 24) are brought together at the joint interface (26).
11. A wind turbine rotor blade (20), comprising:

a first blade section (22) having a first blade interface (38);

a second blade section (24) having a second blade interface (42), wherein the first blade interface (138) engages with the second blade interface (42) across a joint interface (26); and a plurality of temporary clamp assemblies (84) each according to any of claims 1-10 coupled to the first and second blade sections (22, 24) across the joint interface (26).
12. The wind turbine rotor blade of claim 11, wherein the plurality of temporary clamp assemblies (60) provides the only connection between the first and second blade sections (22, 24).
13. A wind turbine (10), comprising:

a tower (12);

a nacelle (14) coupled to the tower (12); and a rotor (16) coupled to the nacelle (14), the rotor (16) including at least one wind turbine rotor blade (20) according to claim 11 or 12.

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14. A method of repairing a sectional wind turbine blade (20) having a first blade section (22) and a second blade section (24) connected together by a clamp assembly (60) across a joint interface (26), comprising:

connecting a plurality of temporary clamp assemblies (84) to the first and second blade sections (22, 24);

disconnecting the clamp assembly (60) that holds the first and second blade sections (22, 24) together such that only the plurality of temporary clamp assemblies (84) hold the first and second blade sections (22, 24) together;

supporting the second blade section (24) with a hoisting system (148); and releasing the plurality of temporary clamp assemblies (84) so as to disengage the second blade section (24) from the first blade section (22).
15. The method of claim 14, further comprising disconnecting a portion of the clamp assembly (60) prior to connecting the plurality of temporary clamp assemblies (84) to the first and second blade sections (22, 24).
16. The method of claim 15, further comprising disconnecting a remaining portion of the clamp assembly (60) after connecting the plurality of temporary clamp assemblies (84) to the first and second blade sections (22, 24).
17. The method of claim 15 of 16, further comprising connecting the plurality of temporary clamp assemblies (84) to connecting elements (68) made available through the disconnection of the portion of the clamp assembly (60).
18. The method of any of claims 14-17, wherein supporting the second blade section (24) with the hoisting system (148) further comprises supporting the second blade section (24) with a ground-based hoisting system.
19. The method of any of claims 14-17, wherein supporting the second blade section (24) with the hoisting system (148) further comprises supporting the second blade section (24) with a wind turbine-based hoisting system.

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20. The method of any of claims 14-19, wherein releasing the plurality of temporary clamp assemblies (84) further comprises remotely releasing the plurality of temporary clamp assemblies (84).
21. The method of claim 20, wherein the plurality of temporary clamp assemblies (84) each include a drive device (132), and wherein remotely releasing the plurality of temporary clamp assemblies (84) further comprises remotely activating the drive devices (132) to release the plurality of temporary clamp assemblies (84).
22. The method of any of claims 14-21, wherein supporting the second blade section (24) with the hoisting system (148) occurs after the plurality of temporary clamp assemblies (84) hold the first and second blade sections (22, 24) together.
23. The method of any of claims 14-21, further comprising:

providing a third blade section (24a);

supporting the third blade section (24a) with the hoisting system (148);

positioning the third blade section adjacent the first blade section (22) at the joint interface (26);

engaging the plurality of temporary clamp assemblies (84) such that only the plurality of temporary clamp assemblies (84) hold the first and third blade sections (22, 24a) together;

connecting the clamp assembly (60) that holds the first and third blade sections (22, 24a) together; and disconnecting the plurality of temporary clamp assemblies (68).
24. The method of claim 23, wherein engaging the plurality of temporary clamp assemblies (84) further comprises automatically engaging the plurality of temporary clamp assemblies (84) as the first and third blade sections (22, 24a) are brought together.

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25. The method of claim 24, wherein the plurality of temporary clamp assemblies (84) includes a biasing mechanism (134) having a spring (140, 140a), and wherein the method further comprises:

deflecting the spring (140, 140a) as the first and third blade sections (22, 24a) are brought together to generate a spring force; and releasing the spring force after the first and third blade sections (22, 24a) engage each other at the joint interface (26) to automatically engage the plurality of temporary clamp assemblies (84) in a snap-fit manner.
26. The method of any of claims 23-25, wherein connecting the clamp assembly (60) that holds the first and third blade sections (22, 24a) together further comprises connecting a portion of the clamp assembly (60) after engaging the plurality of temporary clamp assemblies (84).
27. The method of claim 26, further comprising connecting a remaining portion of the clamp assembly (60) after disconnecting the plurality of temporary clamp assemblies (84).
28. The method of claim 27, further comprising connecting the remaining portion of the clamp assembly (60) to connecting elements (68) made available through the disconnection of the plurality of temporary clamp assemblies (84).
29. The method of any of claims 23-28, further comprising releasing the third blade section (24a) from the hoisting system (148) upon the plurality of temporary clamp assemblies (184) holding the first and third blade sections (22, 24a) together.
30. The method of any of claims 14-29, wherein the repair is an up-tower repair with the wind turbine blade (20) attached to a hub (18) of a wind turbine (10).
31. The method of any of claims 14-29, wherein the repair is a down-tower repair with the wind turbine blade (20) positioned on a support surface.

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32. A method of assembling a sectional wind turbine blade (20) having a first blade section (22) and a second blade section (24), comprising:

supporting the first blade section (22) in a fixed position;

supporting the second blade section (24) with a hoisting system (148);

positioning the second blade section (24) adjacent the first blade section (22) at a joint interface (26);

engaging a plurality of temporary clamp assemblies (68) such that only the plurality of temporary clamp assemblies (68) hold the first and second blade sections (22, 24) together;

connecting a clamp assembly to hold the first and second blade sections together; and disconnecting the plurality of temporary clamp assemblies (68).
33. The method of claim 32, wherein engaging the plurality of temporary clamp assemblies (84) further comprises automatically engaging the plurality of temporary clamp assemblies (84) as the first and second blade sections (22, 24) are brought together.
34. The method of claim 32 or 33, wherein connecting the clamp assembly (60) that holds the first and second blade sections (22, 24) together further comprises connecting a portion of the clamp assembly (60) after engaging the plurality of temporary clamp assemblies (84).
35. The method of claim 34, further comprising connecting a remaining portion of the clamp assembly (60) after disconnecting the plurality of temporary clamp assemblies (84).
36. The method of any of claims 32-35, further comprising releasing the second blade section (24) from the hoisting system (148) upon the plurality of temporary clamp assemblies (84) holding the first and second blade sections (22, 24) together.