Lightning-suppressed wind power generation equipment and wind turbines for wind power generation

Abstract

To provide a lightning strike suppression type wind power generation facility that gives a lightning suppression effect to blades, and can suppress damage to the blades, etc. caused by a lightning strike even if it occurs, and a wind power generation wind turbine.SOLUTION: A lightning strike suppression type wind power generation facility comprises a wind power generation wind turbine 1. The wind power generation wind turbine 1 comprises an erected strut 11, a power generator 12 provided on an upper part of the strut 11, a hub H provided on a drive shaft 13 for rotating and driving the power generator 12, a plurality of blades B provided on the hub H radially around the drive shaft 13, charged bodies E provided at tips of the blades B, a capacitor C provided in an internal space of the hub H, and electric resistance bodies R for converting a portion of discharge energy of a lightning strike on the blades B used as receptors, to thermal energy. The capacitor C includes a grounded first electrode body C1, and a second electrode body C2 made to face the first electrode body C1 via an electric insulation layer. The second electrode body C2 is connected to the charged bodies E via the electric resistance bodies R.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a lightning-suppressed wind power generation facility having a function of suppressing lightning strikes on the wind power generation facility and protecting the wind power generation facility from lightning damage, and to a wind turbine for wind power generation. [Background technology]

[0002] Lightning is an electrical discharge that occurs in the atmosphere. There are various types of lightning discharge, including intracloud discharge, intercloud discharge, and cloud-to-ground discharge. Of these, it is cloud-to-ground discharge (hereafter referred to as lightning) that causes the most damage. Lightning (electrical discharge to the ground) usually occurs under cumulonimbus clouds (clouds commonly known as thunderclouds) when the amount of electric charge inside the cloud becomes so large that a strong electric field is formed that exceeds the electrical breakdown of the air between the cloud and the ground. The mechanism of lightning strikes will now be described in more detail below.

[0003] Positive and negative charges are generated and accumulated within clouds by the interaction of rising air currents and particles (e.g., hail, ice crystals, water droplets) passing through various atmospheric temperature zones. First, moist air near the ground surface is transported upward by rising air currents, and as the temperature of the air decreases with altitude, it eventually becomes saturated with water vapor. And at the -10 degree mark, hail becomes negatively charged and ice crystals become positively charged, with the lighter ice crystals being transported upward by the updraft and the heavier hail being transported downward, resulting in a distribution of positive and negative charges within the cloud. Meanwhile, on the ground, charges of the opposite polarity (positive charges) corresponding to the charge at the cloud base gather and accumulate due to electrostatic induction, causing the voltage between the cloud and the ground to increase. Eventually, the insulation by the atmosphere is broken down, forming an electrical connection, causing a discharge between the cloud and the ground.

[0004] In addition, lightning does not occur until the electric field near the ground is about 100 to 150 times greater than the clear-weather electric field (about +100 to 200 volts per meter). In the case of winter lightning, the electric field near the ground can be an order of magnitude greater, more than 1,000 times greater than the clear-weather electric field. When a strong electric field is formed near the ground, any protruding part of the ground will emit positive and negative ions called "corona discharge" toward the bottom of the thundercloud with the opposite charge in the sky. This is the phenomenon known as the "welcoming discharge" that occurs just before a lightning strikes.

[0005] In the conventional lightning protection concept, it was considered impossible to prevent lightning strikes, and so most methods involved receiving the lightning strike with a needle-type lightning rod (Franklin rod) and directing it to the ground. In other words, conventional lightning rods exacerbate the above-mentioned phenomenon of backscattering, thereby "actively" causing lightning to strike (attract) the lightning rod itself.

[0006] In response to this, the present inventors have proposed a lightning strike suppression device as disclosed in Patent Document 1, in order to protect an object to be protected by minimizing the occurrence of lightning strikes.

[0007] This lightning suppression device has an upper electrode body and a lower electrode body arranged with an electrical insulator between them, and only the lower electrode body is grounded.

[0008] For example, when a thundercloud with negative charges distributed at its base approaches, the opposite charge (positive charges) is distributed on the surface of the earth, and the grounded lower electrode body also becomes positively charged. An upper electrode body is placed on top of this lower electrode body via an insulator containing an air layer, so that the upper electrode body and the lower electrode body function as a capacitor with the lower electrode body grounded.

[0009] This prevents the charge that generates the lightning discharge from flowing from the ground surface to the top surface of the upper electrode body until discharge breakdown of the capacitor occurs, thereby suppressing the lightning discharge that causes lightning strikes. As a result, it has become possible to suppress lightning strikes in a protected area centered around the lightning suppression device. [Prior art documents] [Patent documents]

[0010] [Patent Document 1] Patent No. 5839331 Summary of the Invention [Problem to be solved by the invention]

[0011] Incidentally, in recent years, wind power generation facilities have been gaining attention as a type of power generation device that utilizes renewable energy.

[0012] This wind power generation facility is configured such that a generator covered by a nacelle is installed on the top of a support column, and a plurality of blades are attached to this generator for rotating the generator. Furthermore, some of the larger blades have a length of more than 100 m.

[0013] In this way, the upper part of the wind power generation facility is located in a position close to the thundercloud, and the tips of the blades in particular are easily struck by lightning because they approach the closest position to the thundercloud as a result of rotation.

[0014] For this reason, the inventors have come to the conclusion that it would be effective to impart the above-mentioned lightning suppression function to the tips of the blades in order to suppress lightning strikes on wind power generation facilities. On the other hand, even if the tip of the blade is given the above-mentioned lightning suppression function, the effect obtained is merely to "suppress" lightning strikes, and there are cases in which lightning strikes may still occur. In this case, there is a risk that the blades or the wind power generation facility itself may be damaged by a transient so-called lightning surge.

[0015] The present invention has been made in consideration of the above-described situation, and has an object to provide a lightning-suppression type wind power generation facility and a wind turbine for wind power generation that can provide a lightning suppression effect on the blades and also suppress damage to the blades, etc., even if lightning does strike. [Means for solving the problem]

[0016] In order to solve the above problems, the present invention provides a wind turbine for wind power generation, The wind turbine for wind power generation comprises an upright support, a generator attached to the top of the support, a hub attached to a drive shaft that rotates and drives the generator, a plurality of blades radially attached to the hub around the drive shaft, charged bodies attached to the tips of the blades, a capacitor provided in the internal space of the hub, and an electrical resistor that converts a portion of the discharge energy of a lightning strike, with the blades acting as receptors, into thermal energy; the capacitor includes a first electrode body that is grounded and a second electrode body that faces the first electrode body via an electrical insulating layer; The second electrode body is connected to the charged body via the electrical resistor.

[0017] According to the present invention, for example, if a support pillar is erected on the ground, when a thundercloud with negative charges distributed at the cloud base approaches the wind power generation equipment, the opposite charge (positive charges) is distributed on the surface of the ground, and similarly, the first electrode body, which is grounded and forms part of the capacitor, is also positively charged.

[0018] Since the second electrode body faces the first electrode body via an electrically insulating layer (air layer), the second electrode body is negatively charged by the function of a capacitor. Then, the charged body electrically connected to the negatively charged second electrode body also becomes negatively charged.

[0019] In this way, when the blade tip and the cloud base become the same charge, the oncoming discharge from the blade tip toward the thundercloud, which is the cause of lightning strikes, is suppressed until discharge breakdown of the capacitor occurs. Due to this action, the generation of upward streamers around the tips of the blades positioned at the highest positions is reduced, and lightning strikes on the blades and their surrounding areas are suppressed.

[0020] Here, in the present invention, the second electrode body is connected to the charged body via an electric resistor. This means that even if lightning strikes a blade, the voltage and discharge energy from the lightning strike can be dispersed to the electrical resistor and the ground wire, thereby reducing damage to the wind power generation equipment, including the blades. In addition, heat generated during a lightning strike can be dispersed over the electrical resistor, thereby preventing localized heating of the blade.

[0021] In addition, in the present invention, the capacitor that constitutes the main part of the device for suppressing the occurrence of the aforementioned return discharge is installed in the internal space of the hub. This makes it possible to utilize the dead space inside the hub, and equipment can be installed without providing new installation space or requiring any processing on the blades. In addition, since the lightning suppression equipment can be positioned on the center line of rotation of the drive shaft that is rotated by the hub, i.e., the blades, the center of rotation of the equipment can easily be aligned with the center of rotation of the drive shaft.

[0022] In a preferred embodiment of the present invention, the electrical resistor has a generally elongated shape extending over substantially the entire length of the blade.

[0023] With this configuration, the voltage and discharge energy that the blades receive when struck by lightning, as well as the heat generated by the blades, can be more effectively dispersed.

[0024] In a preferred embodiment of the present invention, the electrical resistor is formed by a support tube connected at both ends to the charged body and the second electrode body, and a non-metallic heating element enclosed inside the support tube.

[0025] With this configuration, in manufacturing the electrical resistor, an appropriate material can be selected as the non-metallic heating element to be enclosed depending on the environment of the installation location, etc., thereby improving manufacturing convenience.

[0026] In a preferred embodiment of the present invention, the first electrode body and the second electrode body are formed as cylindrical bodies of different diameters from a conductive material and are arranged approximately coaxially, and the electrical insulation layer is formed between the first electrode body and the second electrode body.

[0027] With this configuration, air, which has a high insulating effect, is used as the electrical insulation layer, which ensures that electric charge is applied to each electrode body, while also reducing the number of components that make up the capacitor, thereby reducing the cost of the capacitor.

[0028] In a preferred embodiment of the present invention, a plurality of unit capacitors are disposed between the first electrode body and the second electrode body.

[0029] With this configuration, the first electrode body and the second electrode body can be connected uniformly and firmly with a uniform gap therebetween, and the electrical insulating layer can be reliably formed, while the rigidity of the capacitor can be increased.

[0030] In a preferred embodiment of the present invention, the plurality of unit capacitors are disposed between the first electrode body and the second electrode body, radially arranged about a center line thereof.

[0031] With this configuration, the weight of the unit capacitors can be easily and uniformly distributed around the center of rotation of the drive shaft, ensuring smooth rotation of the blades and the drive shaft.

[0032] The present invention also provides a wind turbine for wind power generation, The lightning suppression means is provided at the tip of the blade, and an electric resistor converts a part of the discharge energy of the lightning, which uses the blade as a receptor, into thermal energy, the lightning suppression means includes a first electrode body formed in a substantially spherical shell shape having an internal space, a second electrode body arranged in the internal space at a distance from the first electrode body, and an electrical insulator interposed between the first electrode body and the second electrode body; The electrical resistor has a generally elongated shape extending along the extension direction of the blade, An opening is formed in a part of a shell wall of the first electrode body to connect the internal space to the outside, and a connecting tube is protruded from an edge of the opening toward the outside, One end of the electrical resistor inserted through the connecting tube and the opening is fixed to the second electrode body, the electrical insulator is provided to cover the inner and outer surfaces of the connecting tube and the electrical resistor, and is fixed to the connecting tube and the electrical resistor by a connecting means formed of an electrical insulating material; The other end of the electrical resistor is electrically connected to a ground wire.

[0033] According to the present invention, it is possible to reduce the occurrence of upward streamers from the blades toward the thunderclouds, thereby suppressing the occurrence of lightning strikes, and the electrical resistor can reduce damage to the wind power generation equipment, including the blades, when lightning strikes the blades, and prevent localized heating of the blades. Effect of the Invention

[0034] According to the present invention, it is possible to provide a lightning-suppression type wind power generation facility and a wind turbine for wind power generation, which have a lightning suppression effect on the blades and are capable of suppressing damage to the blades, etc., even if lightning does strike, [Brief description of the drawings]

[0035] [Figure 1] 1 is a schematic diagram showing a lightning-suppressed wind power generation facility according to an embodiment of the present invention. [Diagram 2] FIG. 1 is a perspective view showing an upper portion of a wind turbine for wind power generation according to an embodiment of the present invention. [Diagram 3] FIG. 2 is an enlarged vertical cross-sectional view showing a blade according to an embodiment of the present invention. [Figure 4] FIG. 2 is an enlarged vertical cross-sectional view showing an electric resistor according to an embodiment of the present invention. [Diagram 5] FIG. 2 is a longitudinal sectional view showing a nacelle and a hub according to the embodiment of the present invention. [Figure 6]1A and 1B are diagrams showing a capacitor according to an embodiment of the present invention, in which (a) is a longitudinal sectional view of a unit capacitor, and (b) is a sectional view of the capacitor taken along line PP'. [Figure 7] 13A and 13B are diagrams illustrating a modified example of a capacitor according to an embodiment of the present invention. [Figure 8] FIG. 13 is a diagram showing a modified example of the wind turbine for wind power generation according to the embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0036] A lightning-suppressed wind power generation facility (hereinafter simply referred to as wind power generation facility) according to an embodiment of the present invention will be described below with reference to Figs. 1 to 6. The embodiment described below is merely an example of the present invention, and the present invention is not limited to the embodiment described below. In these drawings, the symbol X indicates a wind power generation facility according to this embodiment.

[0037] <Configuration> As shown in FIG. 1, the wind power generation facility X includes a wind turbine 1 (hereinafter simply referred to as wind turbine 1) that generates electricity, and a power transmission facility 3 that transmits the electricity generated by the wind turbine 1 via a power transmission line 2.

[0038] As shown in Figures 1 to 3, the wind turbine 1 has a pillar 11 erected on the ground G, a generator 12 mounted on the top of the pillar 11, a hub H mounted on a drive shaft 13 that rotates and drives the generator 12, a plurality of blades B arranged radially on the hub H around the drive shaft 13, a charged body E mounted on the tip of the blade B, a capacitor C provided in the internal space of the hub H for supplying an electric charge to the charged body E, and an electrical resistor R for converting a portion of the discharge energy of a lightning strike, with the blade B as a receptor, into thermal energy.

[0039] In addition, the wind turbine 1 has a transmission 14 and a rotating electrical contact 15 . The transmission 14, the generator 12, and a part of the drive shaft 13 are housed in the nacelle N. A rotating electrical contact 15 is interposed between the nacelle N and the hub H. The configurations of the nacelle N (the generator 12, the drive shaft 13, the transmission 14), the hub H, and the rotary electrical contacts 15 are similar to those of known wind turbines for wind power generation.

[0040] As shown in FIG. 3, the blade B has a hollow portion k formed therein over almost the entire length. In addition, blade B has a flange f1 at its base, and flange f1 is fastened to flange f2 provided on hub H by a number of fastening members t (bolts and nuts), thereby fixing blade B to hub H. The blades B are formed of fiber-reinforced plastic such as fiberglass, similar to known wind turbines for wind power generation.

[0041] The charged body E is electrically connected to one of the electrodes of the capacitor C via an electrical resistor R provided inside the blade B. In addition, the charged body E is provided at the tip of the blade B via an electrical insulator I.

[0042] As shown in FIG. 4, the electrical resistor R has an elongated, approximately cylindrical shape extending over approximately the entire length of the blade B, and in this embodiment includes a support tube R1 and a non-metallic heating element R2 enclosed inside the support tube R1.

[0043] The support tube R1 is composed of a support tube main body R11 having both ends open, and a cover portion R12 that closes each opening of the support tube main body R11. In this case, the support tube body R11 can be made of an insulator, and the cover portion R12 can be made of a conductor.

[0044] The non-metallic heating element R2 is filled in the support cylinder R1, and can be made of, for example, ceramics containing as its main component a material selected from the group including SiC, MoSiO2, and ZrO2. Furthermore, the non-metallic heating element R2 may be in the form of a powder, a sintered body, or a porous body, and there are no limitations on the materials and their ratios. In addition, the material of the non-metallic heating element R2 may also be a graphite electrode made of ceramics whose main component is graphite, or it may be a flexible conductive structure such as a conductive gel, conductive rubber, or conductive elastomer.

[0045] Here, the electric resistor R has male threads m formed on both ends thereof, and the male threads m and fixing means T fix and support the electric resistor R in the hollow portion k.

[0046] More specifically, as shown in FIG. 3, the fixing means T is formed by a first plate T1 provided in the hollow portion k and abutting against the base end of the charged body E, a second plate T2 hooked onto the base end of the blade B, and a plurality of nuts T3 screwed into each male thread portion m. The first plate T1 and the second plate T2 can be configured as insulators, with an electric resistor R passing through each of them.

[0047] The male screw portion m on the charged body E side is screwed into a screw hole h formed in the charged body E and communicating with the hollow portion k. In addition, the nut T3 on the charged body E side is screwed onto the male thread portion m in such a manner that the nut T3 and the charged body E sandwich the first plate T1, thereby connecting the charged body E and the electrical resistor R. Furthermore, a metal plate j, through which an electric resistor R is provided and passes, is clamped and fixed between the nut T3 on the hub H side and the second plate T2, and an electric wire W is attached to the metal plate j.

[0048] With the above-mentioned configuration, the second electrode body C2 is electrically connected to the charged body E via the electric resistor R (and the fixing means T and the electric wire W).

[0049] As shown in FIG. 5, the capacitor C is incorporated in the internal space of the hub H coaxially with the hub H. In detail, the capacitor C includes a first electrode body C1 and a second electrode body C2, a plurality of unit capacitors C3 formed of an insulating material and connecting each of the electrode bodies C1, C2 at a predetermined interval, and a spacer C4 formed of an insulating material and fixing each of the electrode bodies C1, C2 to the hub H.

[0050] The first electrode body C1 and the second electrode body C2 are formed in a cylindrical shape from a conductive material, and the diameter of the first electrode body C1 is smaller than the diameter of the second electrode body C2. Furthermore, each unit capacitor C3 is interposed between these and the electrode bodies C1, C2 are fixed, so that they are held at a predetermined interval and their respective axes are aligned.

[0051] A spacer C4 is attached to the outer periphery of the second electrode body C2, and each electrode body C1, C2 is mounted within the internal space of the hub H by fixing this spacer C4 to the inner surface of the hub H using bolts, adhesive, etc.

[0052] The first electrode body C1 and the second electrode body C2 thus mounted have their central axes aligned with the rotation axis of the drive shaft 13. In addition, a rotary electrical contact 15 is attached to the first electrode body C1, and the first electrode body C1 is electrically connected to a ground line L via this rotary electrical contact 15. Furthermore, the second electrode body C2 is electrically connected to a charged body E via an electric wire W. An access hole d that connects the inside of the first electrode body C1 and the second electrode body C2 to the outside of the capacitor C is formed on the side surface of each of the first electrode body C1 and the second electrode body C2.

[0053] As shown in FIG. 6(a), the unit capacitor C3 includes a cylindrical holder C31 made of an electrically insulating material such as ceramics, and unit electrode bodies C32 and C33 provided at the upper and lower ends of the holder C31.

[0054] The holder C31 is formed in a cylindrical shape, and an explosion-proof ventilation hole C31a is provided in the peripheral wall thereof.

[0055] The electrode units C32 and C33 are made of a conductive material and have projections C32a, C32b, C33a, and C33b on their upper and lower surfaces, respectively. Furthermore, the projections C32b and C33b are provided with screw holes C32c and C33c, respectively.

[0056] As shown in FIG. 6(b), a plurality of unit capacitors C3 having the above configuration are radially arranged in a space formed between the first electrode body C1 and the second electrode body C2.

[0057] Then, the outer unit electrode body C32 is screwed to the second electrode body C2, and the inner unit electrode body C33 is screwed to the first electrode body C1, thereby fixing each of the electrode bodies C1 and C2 coaxially and maintaining a predetermined gap between them, thereby forming the capacitor C. In FIG. 6(b), the spacer C4 is omitted.

[0058] <Effects> In the wind power generation facility X according to this embodiment configured as described above, wind energy is converted into rotational motion by the plurality of blades B, and the generator 12 is driven by this rotational motion to generate power.

[0059] At this time, as shown in Figure 1, when a thundercloud with negative charges distributed at the cloud base approaches, the opposite charge (positive charge) is distributed on the surface of the ground G, and the first electrode body C1 of the capacitor C, which is grounded to the ground G, also becomes positively charged.

[0060] As a result, the second electrode body C2, which faces the first electrode body C1 via an electrical insulating layer (an air layer in this embodiment), is negatively charged by the action of the capacitor C. Further, the charged body E, which is electrically connected to the second electrode body C2 via the electrical resistor R and is maintained in an electrically insulated state with respect to the ground G, also becomes negatively charged.

[0061] In this way, when charged body E becomes negatively charged, an area where negative charges are distributed is formed around the tip of blade B, i.e., above wind power generation equipment X, and is confronted by the negative charges distributed at the base of the thundercloud.

[0062] This makes it difficult for upward streamers to occur around the tip of blade B, which is positioned at the highest position, and suppresses lightning strikes on blade B and its surrounding area. Furthermore, since the electrical resistor R has an approximately elongated shape extending over almost the entire length of the blade B, the voltage and discharge energy that the blade B receives during a lightning strike, as well as the heat generated by the blade B, can be more effectively dispersed.

[0063] Furthermore, since the electrical resistor R is formed of a support tube R1 and a non-metallic heating element R2, when manufacturing the electrical resistor R, an appropriate material can be selected for the enclosed non-metallic heating element R2 in accordance with the environment of the installation location, etc., thereby improving manufacturing convenience.

[0064] In addition, due to the shape and arrangement of the first electrode body C1 and the second electrode body C2, air, which has a high insulating effect, can be used as an electrical insulating layer to reliably charge each electrode body C1, C2, while the number of components of the capacitor C can be reduced, thereby reducing the cost of the capacitor C.

[0065] Furthermore, the unit capacitor C3 can connect the first electrode body C1 and the second electrode body C2 uniformly and firmly, reliably forming an electrical insulating layer, and increasing the rigidity of the capacitor C.

[0066] Furthermore, by arranging multiple unit capacitors C3 radially, the weight of the unit capacitors C3 can be easily and uniformly distributed around the center of rotation of the drive shaft 13, making the rotation of the blade B and the drive shaft 13 smooth.

[0067] Hereinafter, modifications of the wind turbine 1' and the capacitor C' according to the embodiment of the present invention will be described with reference to Figs. FIG. 7 is an enlarged vertical cross-sectional view of a main portion of a blade B of the wind turbine 1'. Moreover, Figure 8(a) is a longitudinal cross-sectional view showing a nacelle N and hub H including a capacitor C', and Figure 8(b) is a cross-sectional view of the capacitor C' taken along line QQ', in which the first electrode body C1 and the second electrode body C2 are roughly indicated by dashed double-dotted lines.

[0068] <Configuration (Windmill 1´)> As shown in FIG. 7, the wind turbine 1' has a lightning suppression means A provided at the tip of the blade B, and an electric resistor R that converts part of the discharge energy of the lightning, which uses the blade B as a receptor, into thermal energy.

[0069] The lightning suppression means A includes a first electrode body A1 formed in an approximately spherical shell shape having an internal space V, a second electrode body A2 arranged in the center of the internal space V at a distance from the first electrode body A1, and an electrical insulator A3 interposed between the first electrode body A1 and the second electrode body A2.

[0070] As described with reference to FIG. 4 etc., the electric resistor R includes a support cylinder R1 and a non-metallic heating element R2 enclosed inside the support cylinder R1. Moreover, the electrical resistor R has two annular grooves g1, g2 formed on the tip side, and a male screw portion m formed only on the base end portion.

[0071] The fixing means T is formed by a first connecting means T1 for connecting the electrical resistor R to the second electrode body A2, a second connecting means T2 for connecting the electrical resistor R to the electrical insulator A3 and the connecting tube A13, a third connecting means T3 for connecting the electrical resistor R to the blade B, and a plate T4 clamped between the third connecting means T3 and the base end of the blade B.

[0072] The first electrode body A1 is composed of a substantially spherical shell-shaped first electrode body main body A11, an opening A12 formed in part of the shell wall of the first electrode body main body A11 and connecting the internal space V to the outside, and a connecting tube A13 protruding outward from the edge of the opening A12. The first electrode body A11 is made of a conductive material such as stainless steel and is formed into a spherical shell having a perfectly circular cross section, with a portion of the shell being cut away to form an opening A12. An outwardly extending connecting tube A13 is integrally provided on the edge of the opening A12.

[0073] One end of an electric resistor R is fixed to the second electrode body A2 and inserted through the connecting tube A13 and the opening A12. The second electrode body A2 is a solid sphere made of a conductive material, and is fixed by a first connecting means T1 to the insertion end of the electrical resistor R inserted into the first electrode body A11.

[0074] The electrical insulator A3 is provided to cover the inner and outer surfaces of the connecting tube A13 and the electrical resistor R, and is fixed to the electrical resistor R together with the connecting tube A13 by second connecting means T2 made of an electrical insulating material. In addition, the electrical insulator A3 is composed of a first electrical insulator A31 that covers the tip of the electrical resistor R and fills the gap between the electrical resistor R and the connecting tube A13, and a second electrical insulator A32 that is provided to cover the lower peripheral surface and bottom surface of the first electrical insulator A31. A reinforcing ring r is interposed between the overlapping portion of the first electrical insulator A31 and the connecting tube A13.

[0075] The portion where the male thread portion m of the electrical resistor R is formed penetrates a plate T4 which is engaged with a locking step formed at the base end of the blade B, and a third connecting means T3 (nut) is screwed into this penetrating portion.

[0076] Then, the third connecting means T3 is pressed against the plate T4, and the blade B is clamped lengthwise between this third connecting means T3 and the electrical insulator A3 fixed to the electrical resistor R, so that the electrical resistor R, the first electrode body A1, the second electrode body A2 and the electrical insulator A3 are fixed to the blade B. The grounded wire L is electrically connected to the plate T4.

[0077] The upper second connecting means T2 is made of an electrically insulating material, and is screwed into the first electrical insulator A31 in a penetrating state, and is pressed into the annular groove g1 of the electrical resistor R. The lower second connecting means T2 is screwed through the second electrical insulator A32, the reinforcing ring r, and the first electrical insulator A31, and is pressed into the annular groove g2 of the electrical resistor R.

[0078] As a result, the lightning suppression means A is fixed to the blade B with relative movement of the blade B in the longitudinal direction being restricted.

[0079] <Effect(Windmill 1´)> According to this modified example, using the same principle as wind turbine 1, when a thundercloud with negative charges distributed at the cloud base approaches, the second electrode body A2 electrically connected via the ground wire L becomes positively charged, and the first electrode body A1 arranged via an insulator becomes negatively charged due to the action of the capacitor. Here, as the windmill rotates, the first electrode body A1 faces the thundercloud, and because they are charged with the same negative charge, the generation of upward streamers from the blade B toward the thundercloud is unlikely, thereby suppressing the occurrence of lightning strikes.

[0080] In this modified example, the electrical resistor R provided inside the blade B can reduce damage to the wind power generation equipment X including the blade B when lightning strikes the blade B, and can prevent localized heating of the blade B.

[0081] In addition, according to this modified example, the first electrode body A1 is spherical and the tip of the blade B is positioned at the base of the connecting tube A13 of the first electrode body A1, so that the first electrode body A1 can be exposed as much as possible from the blade B. This makes it possible to increase the area of ​​the first electrode body A1 exposed upward even when the lightning suppression means A is moved downward, thereby expanding the area of ​​negative charge that faces the thundercloud. As a result, the effect of suppressing the generation of upward streamers is enhanced, and lightning strikes can be effectively suppressed.

[0082] <Configuration (Capacitor C´)> As shown in Figure 8, capacitor C' has a structure in which two circular conductive plates are arranged at a distance from each other and fixed within hub H via an insulator so that one serves as the first electrode body C1 and the other serves as the second electrode body C2. In this case, it is preferable from the viewpoint of rotational balance that the disk-shaped first electrode body C1 and second electrode body C2 are arranged coaxially with the drive shaft 13 as in the illustrated example.

[0083] In addition, by adjusting the center of gravity and center of rotation of the first electrode body C1 and the second electrode body C2, the electrode bodies C1 and C2 can be formed into a rectangular, polygonal, elliptical or other shape in addition to being disc-shaped.

[0084] Even in a structure in which the first electrode body C1 and the second electrode body C2 are arranged within the hub H in this manner, a configuration in which multiple unit capacitors C3 are arranged between the first electrode body C1 and the second electrode body C2 can be adopted. When a plurality of unit capacitors C3 are arranged, a large number of them can be arranged by arranging them in a ring shape around the central axis of the first electrode body C1 and the second electrode body C2.

[0085] <Effect (Capacitor C´)> According to this modification, substantially the same effects as those of capacitor C can be obtained, but in particular, the capacitor itself can be produced simply and at lower cost.

[0086] The shapes and dimensions of the components shown in the above-described embodiment are merely examples and can be modified in various ways based on design requirements, etc.

[0087] For example, the electrical resistor R is not limited to the above configuration, and may be formed as a solid rod-shaped body using various materials used for the non-metallic heating element R2 exemplified above. In addition, the electrical resistor R may be entirely made of a metal heating element selected from the group including, for example, Fe, Cr, Al, Cu, Ni, a Cu-Ni alloy, a Cu-Mn alloy, a Ni-Al alloy, a Ni-Cr alloy, and an Fe-Cr-Al alloy. Furthermore, the shape of the electrical resistor R is not limited to a cylindrical shape, and may be, for example, a foil, wire, strip, or flat braid, and there is no restriction on its shape. It may be provided with a round or L-shaped terminal at its tip for connection. [Explanation of symbols]

[0088] X Wind power generation facilities 1, 1´ Wind turbine for wind power generation 2. Power Lines 3. Power transmission facilities E Charged body B-Blade R Electrical resistor R1 support tube R2 Non-metallic heating element C, C´ capacitor C1 1st electrode body C2 Second electrode body C3 Unit Capacitor C4 Spacer A. Lightning strike prevention measures A1 1st electrode body A2 2nd electrode body A3 Electrical insulators G ground

Claims

1. Equipped with wind turbines for wind power generation, The wind turbine for wind power generation comprises an upright support, a generator attached to the top of the support, a hub attached to a drive shaft that rotates and drives the generator, a plurality of blades radially attached to the hub around the drive shaft, charged bodies attached to the tips of the blades, a capacitor provided in the internal space of the hub, and an electrical resistor that converts a portion of the discharge energy of a lightning strike, with the blades acting as receptors, into thermal energy; The capacitor includes a first electrode body that is grounded, and a second electrode body that faces the first electrode body via an electrical insulating layer, The second electrode body is connected to the charged body via the electrical resistor, The electrical resistor has a roughly elongated shape extending over roughly the entire length of the blade, and includes a support tube connected to the charged body and the second electrode body at both ends, and a non-metallic heating element sealed inside the support tube.

2. the first electrode body and the second electrode body are formed as cylindrical bodies having different diameters from each other using a conductive material, and are arranged substantially coaxially; The lightning-suppressed wind power generation facility according to claim 1 , wherein the electrical insulating layer is formed between the first electrode body and the second electrode body.

3. The lightning-suppressed wind power generation facility according to claim 2 , wherein a plurality of unit capacitors are arranged between the first electrode body and the second electrode body.

4. The lightning-suppressed wind power generation facility according to claim 3 , wherein the plurality of unit capacitors are disposed between the first electrode body and the second electrode body, radially arranged around a center line thereof.

5. The lightning suppression means is provided at the tip of the blade, and an electric resistor converts a part of the discharge energy of the lightning, which uses the blade as a receptor, into thermal energy, the lightning suppression means includes a first electrode body formed in a substantially spherical shell shape having an internal space, a second electrode body arranged in the internal space at a distance from the first electrode body, and an electrical insulator interposed between the first electrode body and the second electrode body; the electrical resistor has a generally elongated shape extending along the extension direction of the blade, and includes a support tube connected to the second electrode body at one end thereof, and a non-metallic heating element enclosed inside the support tube, An opening is formed in a part of a shell wall of the first electrode body to connect the internal space to the outside, and a connecting tube is provided protruding outward from an edge of the opening, One end of the electrical resistor inserted through the connecting tube and the opening is fixed to the second electrode body, the electrical insulator is provided to cover the inner and outer surfaces of the connecting tube and the electrical resistor, and is fixed to the connecting tube and the electrical resistor by a connecting means formed of an electrical insulating material; The other end of the electrical resistor is electrically connected to a ground wire.

Images