Heightening tool for assembling impeller of wind turbine generator and impeller assembling method

Abstract

The heightening tool comprises a heightening base and a transition section, the transition section is used for supporting and connecting a hub, the heightening base is formed by combining three base supports of the same structure, and the base supports correspond to blade mounting holes of the hub in position respectively. Each base support is provided with two inclined corner connecting parts which are symmetrically arranged, the base supports can be connected end to end through the inclined corner connecting parts to form an annular supporting structure, and the top contours of the base supports are matched with the lower end face of the transition section and used for supporting and connecting the transition section. The heightened base not only provides support for the transition section and the hub, but also further heightens the hub on the basis of the transition section, so that the hub is convenient to assemble, and the assembly efficiency is improved; by adjusting the connection mode and position between the base and the support, the hub and the transition section with larger sizes can be adapted, the adaptability is improved, and the production cost is saved.

Description

Technical Field

[0001] The present invention relates to the technical field of wind power generation, and in particular to a heightening tool for assembling an impeller of a wind turbine generator set and an impeller assembling method. Background Art

[0002] As a new type of renewable energy, wind energy has been valued by more and more countries, and wind power generation technology has been increasingly optimized. The hub of a wind turbine is one of the important components of a wind turbine. In the structure of a wind turbine, the hub is used to connect the main shaft and the blades, and transmit the load of the wind force on the blades to the main shaft and the gearbox. As an important load-bearing component in a wind turbine, the hub needs to have sufficient strength and rigidity and good shock absorption performance to reduce the load impact of the blades on the main shaft. At present, the hub size of large-power wind turbines is generally large. Due to the limitation of transportation height, the hub transportation no longer requires a hub transportation base, but this also leads to the need for a heightening tool to fix and support the hub and raise it when assembling the hub cover, and at the same time facilitate the installation of the hub cover and the components in the hub to improve assembly efficiency.

[0003] In addition, due to the large size and weight of the hub of a high-power wind turbine, how to design a hub assembly bracket with high support strength and advantages in terms of weight, cost and ease of assembly and disassembly is an urgent issue to be solved. Moreover, with the development of more and more models in the wind power industry, the hub size is also constantly changing. If each size of hub is equipped with a hub heightening tool, it will cause waste of resources and increase costs, so a heightening tool that can be used for the assembly of hubs of various sizes is needed. Summary of the invention

[0004] A series of simplified concepts are introduced in the Summary of the Invention, which will be further described in detail in the Detailed Description of the Invention. The Summary of the Invention does not mean to attempt to define the key features and essential technical features of the claimed technical solution, nor does it mean to attempt to determine the scope of protection of the claimed technical solution.

[0005] In order to at least partially solve the above-mentioned problems, the present invention provides a heightening tool for assembling a wind turbine impeller, comprising a heightening base and a transition section, wherein the transition section is constructed as an annular structure whose upper end face matches the main shaft side end face of the hub, and is used to support the hub and be connected to the hub by bolts, and the heightened base is formed by a combination of three base brackets of the same structure, and the positions of each base bracket correspond to the positions of the blade mounting holes of the hub, respectively, and the base bracket is constructed as a roughly rectangular contour structure with two symmetrically arranged inclined corner connecting parts, and the three base brackets can be connected end to end to each other through their respective inclined corner connecting parts to form an annular support structure, and the top contour of the heightened base matches the lower end face of the transition section, and is used to support the transition section and be connected to the transition section by bolts.

[0006] Furthermore, the base bracket includes a frame structure formed by welding angle steels, two side plates composed of channel steels and two connecting plates composed of steel plates. The side plates and the connecting plates are respectively welded to the frame structure, and the connecting plates are provided with bolt holes for interconnecting the base brackets.

[0007] Furthermore, the heightening tooling also includes three extension brackets of the same structure, and the extension brackets include two steel beams and at least one cross beam that are detachably connected to the two side plates of the base bracket, respectively. The steel beams extend radially along the transition section, and the two ends of the cross beam are respectively connected to the two steel beams.

[0008] Furthermore, the side panel is provided with a strip steel plate and bolt holes located on the upper and lower sides of the strip steel plate, and the steel beam is provided with two steel plates with bolt holes at one end thereof connected to the side panel, and the two steel plates are spaced apart in the height direction at a distance matching the strip steel plate, so that the extended bracket and the base bracket are connected to each other by bolts and a keyway structure.

[0009] Furthermore, the base support also includes a platform plate arranged on the top of the frame structure, and the platform plate is connected to the longitudinal angle steel and two transverse angle steels at the upper end of the inner side of the frame structure by bolts, so that the platform plate is located on the inner side of the transition section as a whole.

[0010] Furthermore, the transition section includes an upper ring plate connected to the wheel hub by bolts, a lower ring plate connected to the raised base by bolts, a cylindrical body whose upper and lower ends are welded to the upper ring plate and the lower ring plate respectively, and a plurality of webs evenly distributed along the circumferential direction, wherein the upper side edge, lower side edge and inner side edge of the web are respectively welded to the lower end surface of the upper ring plate, the upper end surface of the lower ring plate and the outer side surface of the cylindrical body.

[0011] Furthermore, the lower ring plate includes three first sections with straight outer edges and three second sections with arc-shaped outer edges, and the first sections and the second sections are alternately arranged so that the outer edges of the three first sections are flush with the outer edges of the three base brackets respectively.

[0012] Furthermore, the lower ring plate is provided with an outer bolt hole and an inner bolt hole respectively located on the outer side and the inner side of the cylindrical body, and both the outer bolt hole and the inner bolt hole are long round bolt holes extending along the length direction of the angle steel connected thereto.

[0013] The present invention also provides an impeller assembly method using the above-mentioned heightening tooling, comprising the following steps:

[0014] S1: Arrange the three base brackets symmetrically to form a raised base;

[0015] S2: Connect the transition section to the raised base with bolts;

[0016] S3: Connect the hub to the transition section by bolts so that the three blade mounting holes of the hub correspond to the three base brackets respectively;

[0017] S4: Assemble components and hub cover in the wheel hub.

[0018] Furthermore, the impeller assembly method further comprises the following steps:

[0019] S5: transporting the assembled hub to the wind farm;

[0020] S6: Connect the heightened base, transition section and lengthened bracket to form a heightened tooling at the wind farm;

[0021] S7: Install the assembled wheel hub to the transition section;

[0022] S8: hoist the three blades separately and install them to the hub;

[0023] S9: Dismantle the heightening tooling and lift the assembled impeller as a whole.

[0024] The heightening tooling of the present invention comprises two parts, a heightening base and a transition section. The heightening base not only provides support for the transition section and the wheel hub above it, but also further elevates the wheel hub on the basis of the transition section due to its own height, thereby facilitating the assembly of the wheel hub and improving assembly efficiency. The heightening base is formed by three base brackets of the same structure connected by bolts, which is convenient for production and processing, and is convenient for disassembly and assembly, thereby facilitating transportation and on-site assembly. By adjusting the connection method and position between the base brackets, it can adapt to larger-sized wheel hubs and transition sections, thereby improving adaptability and saving production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The following drawings of the present invention are used as part of the present invention for understanding the present invention. The drawings show the embodiments of the present invention and their descriptions, and are used to explain the device and principle of the present invention. In the drawings,

[0026] Figure 1 It is a schematic diagram of the three-dimensional structure of the heightening tooling according to an embodiment of the present invention;

[0027] Figure 2 It is a schematic diagram of the three-dimensional structure of the heightened base according to an embodiment of the present invention;

[0028] Figure 3 is a schematic diagram of the three-dimensional structure of a transition section according to an embodiment of the present invention;

[0029] Figure 4 It is a schematic diagram of the three-dimensional structure of the base support according to an embodiment of the present invention;

[0030] Figure 5 It is a three-dimensional structural schematic diagram of a heightening tooling with an extended bracket;

[0031] Figure 6 It is a schematic diagram of the three-dimensional structure of the extended bracket according to an embodiment of the present invention;

[0032] Figure 7 is a schematic diagram of the three-dimensional structure of a platform plate according to an embodiment of the present invention;

[0033] Figure 8 It is a schematic diagram of the three-dimensional structure of the connecting plate according to an embodiment of the present invention.

[0034] The symbols in the accompanying drawings are as follows:

[0035] 1. Raise the base; 11. Base bracket; 111. Frame structure; 1111. Longitudinal angle steel; 1112. Longitudinal angle steel; 1113. Horizontal angle steel; 1114. Vertical angle steel; 1115. Oblique angle steel; 112. Side plate; 113. Connecting plate; 1131. Bolt hole; 1132. Bolt hole; 1133. Bolt hole; 114. Platform plate; 1141. Bolt hole; 1142. Bolt hole;

[0036] 2. Transition section; 21. Upper ring plate; 211. Long round bolt hole; 22. Lower ring plate; 221. First part; 222. Second part; 223. Outer bolt hole; 224. Inner bolt hole; 23. Cylinder; 24. Web plate;

[0037] 3. Extended bracket; 31. Steel beam; 311. Steel plate; 3111. Bolt hole; 312. Bolt hole; 32. Cross beam; 321. Steel plate; 3211. Bolt hole. DETAILED DESCRIPTION

[0038] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention. The described embodiments are only preferred embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] It should be understood that, unless otherwise defined, the technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art of the present invention. The purpose of the terms used herein is only to describe specific embodiments and is not intended to limit the present invention. Terms such as "parts" and "pieces" that appear in this article can represent both single parts and combinations of multiple parts. The singular forms of "one", "an" and "said / the" are also intended to include plural forms unless the context clearly indicates otherwise. Ordinal numbers such as "first" and "second" are merely identifiers and do not have any other meaning, such as a specific order, etc. Moreover, for example, the term "first component" itself does not imply the existence of a "second component", and the term "second component" itself does not imply the existence of a "first component". When the terms "comprising" and / or "including" are used in this specification, it indicates the presence of the features, wholes, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or combinations thereof. The terms "upper", "lower", "front", "back", "left", "right", "inside", "outside", "center", "vertical", "horizontal" and similar expressions are for illustrative purposes only and are not limiting. The terms "connect", "install", "connected", and "set" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be a communication between the two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances. The features described in this document in one embodiment may be applied to another embodiment alone or in combination with other features, unless the feature is not applicable in the other embodiment or otherwise specified.

[0040] Hereinafter, specific embodiments of the present invention will be described in more detail with reference to the accompanying drawings. These drawings show representative embodiments of the present invention and do not limit the present invention.

[0041] The present invention provides a heightening tool for assembling a wind turbine impeller. Figure 1-8As shown, the heightening tooling includes a heightening base 1 and a transition section 2. The transition section 2 is constructed as an annular structure whose upper end face matches the main shaft side end face of the hub, and is used to support the hub and is connected to the hub by bolts; the heightening base 1 is formed by combining three base brackets 11 of the same structure, and the positions of each base bracket 11 correspond to the positions of the blade mounting holes of the hub, and the base bracket 11 is constructed as a roughly rectangular parallelepiped profile structure with an inclined corner connection portion, and the three base brackets 11 can be connected end to end with each other through their respective inclined corner connections to form an annular support structure, and the top profile of the heightening base 1 matches the lower end face of the transition section 2, and is used to support the transition section 2 and is connected to the transition section 2 by bolts. The elevated base 1 not only provides support for the transition section 2 and the wheel hub above it, but also further elevates the wheel hub on the basis of the transition section 2 due to its own height, which is convenient for installing the wheel hub and improves the installation efficiency; the elevated base 1 can be formed by three base brackets 11 of the same structure connected by respective inclined corner connecting parts and connected by bolts, which is convenient for production and processing, and is convenient for transportation and on-site assembly due to its convenient disassembly and assembly. Moreover, when a larger wheel hub needs to be assembled, the original three base brackets 11 can be used to match the enlarged transition section. Specifically, the three base brackets 11 can be arranged radially outward along the transition section and connected to the enlarged transition section by bolts, and the three base brackets 11 are spaced apart from each other and are not connected to each other.

[0042] According to an embodiment of the present invention, Figure 4As shown, the base support 11 includes a frame structure 111 formed by welding angle steels, two side plates 112 formed by channel steels, and two connecting plates 113 formed by steel plates, and the side plates 112 and the connecting plates 113 are respectively welded to the frame structure 111. Specifically, the frame structure 111 uses a total of 5 specifications of angle steels, including two longitudinal angle steels 1111 located at the upper and lower ends of the inner side, two longitudinal angle steels 1112 located at the upper and lower ends of the outer side, four transverse angle steels 1113 whose two ends are respectively welded to the longitudinal angle steels 1111 and 1112, six vertical angle steels 1114, and four oblique angle steels 1115. Among them, the two ends of the oblique angle steel 1115 are respectively welded to the side plates 112 and the longitudinal angle steel 1111 on the inner side of the frame structure, and the outer side surface of the oblique angle steel 1115 is welded to the connecting plate 113 to form the above-mentioned inclined corner connection part. The main structure of the base bracket 11 adopts a frame structure formed by welding angle steels, and channel steels and connecting steel plates are arranged on the two sides, which can reduce weight and save materials to the greatest extent while ensuring the supporting strength. The angles between the two connecting plates 113 of the base bracket 11 and the inner end faces of the frame structure 111 are both set to 150°, that is, the inclination angle of the inclined corner connection relative to the inner side face of the base bracket 11 where it is located is set to 30°, so that the three base brackets 11 are connected to each other through their respective connecting plates 113 to form a support structure with an equilateral triangle in the inner cross-section, wherein each base bracket 11 supports one-third of the transition section 2; the length and width of the base bracket 11 are set to be substantially equal to the maximum dimensions of the one-third transition section above it in the chord length direction and the radial direction, thereby providing sufficient supporting strength. Figure 4 and Figure 6 As shown, the connecting plate 113 is provided with three groups of bolt holes 1131, 1132, and 1133, respectively, and correspondingly, the upper and lower oblique angle steels 1115 are provided with bolt holes matching the upper and lower groups of bolt holes 1131 and 1133 of the connecting plate 113. During the processing of the base bracket 11, the upper and lower groups of bolt holes 1131 and 1133 of the connecting plate 113 are respectively aligned with the bolt holes of the upper and lower oblique angle steels 1113, and then the connecting plate 113 is welded to the upper and lower oblique angle steels 1113 along the edges; during the assembly of the base 1, the connecting plates of each base bracket 11 are butted against each other and bolted through the three groups of bolt holes 1131, 1132, and 1133. On the basis that the three base brackets 11 are respectively bolted to the upper transition section 2, the base brackets 11 are bolted to form a central symmetrical structure to improve the support strength, which is especially necessary when the hub and the blades are assembled in the wind farm before the impeller is hoisted as a whole.

[0043] like Figure 5 and Figure 6As shown, the heightening tool of the present invention can also include three extension brackets 3 of the same structure. The extension bracket 3 includes two steel beams 31 and at least one cross beam 32 that are detachably connected to the two side plates 112 of the base bracket 11. The steel beams 31 extend along the radial direction of the transition section 2, and the two ends of the cross beam 32 are respectively connected to the two steel beams 31. Channel steel can be used as the main structure of the steel beams 31 and the cross beams 32. In order to strengthen the connection strength between the base bracket 11 and the extension bracket 3, as shown in FIG. Figure 4 and Figure 6 As shown, the side plate 112 of the base bracket 11 is provided with a strip steel plate 1121 and bolt holes 1122 located on the upper and lower sides of the strip steel plate 1121, and the steel beam 31 is welded with two steel plates 311 with bolt holes 3111 at one end thereof connected to the side plate 112, and the two steel plates 311 are spaced apart in the height direction at a distance matching the strip steel plate 1121, so that the extended bracket 3 and the base bracket 11 are connected to each other through bolts and a keyway structure; the other end of the steel beam 31 is provided with a bolt hole 312, and accordingly, steel plates 321 with bolt holes 3211 are respectively welded at both ends of the cross beam 32, so as to be respectively connected to the two steel beams 31 by bolts. The extended bracket 3 is suitable for the situation where the impeller is hoisted as a whole during the on-site installation of the unit. That is, before the impeller is hoisted as a whole, it is necessary to arrange the heightening tooling and the hub on the ground of the wind farm, and then lift the three blades separately and install them to the hub. Since there may be a large overturning moment during the blade installation process, the heightening tooling connected to the bottom of the hub is increased by an extended bracket 3 extending along the length direction of the blade, and the extended bracket 3 is connected to the base bracket 11 by a bolt and keyway structure, which can effectively improve the safety and reliability of the unit during on-site installation.

[0044] According to an embodiment of the present invention, the base support 11 further includes a platform plate 114 disposed on the top of the frame structure 111, and the platform plate 114 is respectively connected to the longitudinal angle steel 1111 and two transverse angle steels 1112 located at the inner upper end of the frame structure 111 by bolts, so that the platform plate 114 is located on the inner side of the transition section 2 as a whole. When assembling the hub, the operator can stand steadily on the platform plate to install the internal components of the hub, thereby improving the assembly efficiency and the safety of the operation. The three platform plates 114 can be located at the positions of the three blade mounting holes of the hub, respectively, so that the operator can perform the corresponding installation operations.

[0045] According to an embodiment of the present invention, the transition section 2 includes an upper ring plate 21 for connecting to the wheel hub by bolts, a lower ring plate 22 connected to the elevated base 1 by bolts, a cylindrical body 23 with upper and lower ends welded to the upper ring plate 21 and the lower ring plate 22, respectively, and a plurality of webs 24 evenly distributed along the circumferential direction. Figure 1 and Figure 3As shown, the lower ring plate 22 includes three first sections 221 with straight outer sides and three second sections 222 with arc-shaped outer sides. The first sections 221 and the second sections 222 are alternately arranged so that the outer sides of the three first sections 221 are respectively flush with the outer sides of the three base brackets 11. In order to provide stable and reliable support, it is necessary to increase the area of ​​the lower ring plate 22 and the corresponding bearing area of ​​the base bracket 11 as much as possible. The above arrangement of the lower ring plate 22 can increase the contact area with the base bracket 11, reduce the weight and floor space, and reserve an inner area for installing the platform plate 114. Furthermore, the center position of each second section 222 of the lower ring plate 22 is pressed against the inclined corner connection portion where the two base supports 11 are interconnected. Accordingly, in order to strengthen the supporting strength of this position, the outer end of the inclined angle steel 1115 is welded to the side plate 112 formed by the channel steel, and the inner end is welded to the longitudinal angle steel 1111, and a vertical angle steel 1114 is added (four of the six vertical angle steels 1114 are located on the inner side of the base support 11). In addition, in addition to being used for interconnecting the base supports 11, the connecting plate 113 is also welded to the upper and lower inclined angle steels 1115 at its upper and lower ends and bolted, respectively, to further improve the supporting strength of the inclined corner connection.

[0046] like Figure 1 and Figure 3 As shown, the upper end of the cylinder 23 is welded to the inner edge of the upper ring plate 21 or the position close to the inner edge. Correspondingly, the upper side, lower side and inner side of the web 24 are welded to the lower end face of the upper ring plate 21, the upper end face of the lower ring plate 22 and the outer side face of the cylinder 23, respectively, to enhance the support strength of the transition section 2. Preferably, the upper ring plate 21 is provided with oblong bolt holes 211 uniformly distributed along the circumferential direction and elongated in the radial direction, thereby increasing the size range of the applicable hub and improving the adaptability. The lower ring plate 22 includes a wider part located outside the cylinder 23 and a narrower part located inside the cylinder 23. The two parts are respectively provided with an outer bolt hole 223 and an inner bolt hole 224. The outer bolt hole 223 and the inner bolt hole 224 are both oblong bolt holes elongated along the length direction of the angle steel connected thereto, so as to avoid connection difficulties caused by processing or installation errors and improve installation efficiency. The wider portion is provided with a plurality of aligned oblong bolt holes near each straight line segment, which are used to be connected with the longitudinal angle steel 1112 at the upper end of the outer side of the frame structure 111 by bolts. Figure 4 and Figure 5As shown, the longitudinal angle steel 1111 at the upper end of the inner side of the frame structure 111 and the transverse angle steel 1113 at the upper end are respectively provided with bolt holes for connecting with the lower ring plate 22 and the platform plate 114; accordingly, the platform plate 114 is provided with at least two bolt holes 1141 aligned in the transverse direction and spaced apart in the longitudinal direction for connecting with the longitudinal angle steel 1111, and at least two bolt holes 1142 aligned in the longitudinal direction and spaced apart in the transverse direction for connecting with the transverse angle steel 1113.

[0047] The present invention also provides an impeller assembly method using the above-mentioned heightening tooling, comprising the following steps:

[0048] S1: Arrange three base brackets 11 symmetrically to form a heightened base 1;

[0049] S2: Connect the transition section 2 to the heightened base 1 by bolts;

[0050] S3: Connect the hub to the transition section 2 by means of bolts, so that the three blade mounting holes of the hub correspond to the three base brackets 11 respectively;

[0051] S4: Assemble components and hub cover in the wheel hub.

[0052] After completing the above steps at the factory, if the impeller needs to be hoisted as a whole at the wind farm, the following steps can be continued:

[0053] S5: transporting the assembled hub to the wind farm;

[0054] S6: Connecting the heightening base 1, the transition section 2 and the lengthening bracket 3 to form a heightening tooling at the wind farm;

[0055] S7: Install the assembled wheel hub to the transition section 2;

[0056] S8: hoist the three blades separately and install them to the hub;

[0057] S9: Dismantle the heightening tooling and lift the assembled impeller as a whole.

[0058] The present invention has been described through the above-mentioned embodiments, but it should be understood that the above-mentioned embodiments are only for the purpose of example and description, and are not intended to limit the present invention to the scope of the described embodiments. In addition, it can be understood by those skilled in the art that the present invention is not limited to the above-mentioned embodiments, and more variations and modifications can be made according to the teachings of the present invention, and these variations and modifications all fall within the scope of the protection claimed by the present invention. The protection scope of the present invention is defined by the attached claims and their equivalents.

Claims

1. A heightening tool for assembling a wind turbine impeller, characterized in that: The invention comprises a raised base (1) and a transition section (2); the transition section (2) is constructed as an annular structure whose upper end face matches the main shaft side end face of the hub, and is used to support the hub and is connected to the hub via bolts; the raised base (1) is formed by combining three base brackets (11) of the same structure, and the positions of the base brackets (11) respectively correspond to the positions of the blade mounting holes of the hub; the base brackets (11) are constructed as a roughly rectangular parallelepiped profile structure having two symmetrically arranged inclined corner connecting parts; the three base brackets (11) can be connected end to end to each other via their respective inclined corner connecting parts to form an annular support structure; the top profile of the raised base (1) matches the lower end face of the transition section (2), and is used to support the transition section (2) and is connected to the transition section (2) via bolts.

2. The heightening tool according to claim 1, characterized in that: The base support (11) comprises a frame structure (111) formed by welding angle steels, two side plates (112) formed by channel steels, and two connecting plates (113) formed by steel plates. The side plates (112) and the connecting plates (113) are respectively welded to the frame structure (111), and the connecting plates (113) are provided with bolt holes (1131, 1132, 1133) for connecting the base supports (11) to each other.

3. The heightening tool according to claim 2, characterized in that: It also includes three extension brackets (3) of the same structure, wherein the extension brackets (3) include two steel beams (31) and at least one cross beam (32) which are detachably connected to the two side plates (112) of the base bracket (11), the steel beams (31) extending radially along the transition section (2), and the two ends of the cross beam (32) are respectively connected to the two steel beams (31).

4. The heightening tool according to claim 3, characterized in that: The side plate (112) is provided with a strip steel plate (1121) and bolt holes (1122) located at the upper and lower sides of the strip steel plate (1121); the steel beam (31) is provided with two steel plates (311) with bolt holes (3111) at one end thereof connected to the side plate (112); the two steel plates (311) are spaced apart in the height direction at a distance matching the strip steel plate (1121), so that the extension bracket (3) and the base bracket (11) are connected to each other through bolts and a keyway structure.

5. The heightening tool according to claim 2, characterized in that: The base support (11) also includes a platform plate (114) arranged on the top of the frame structure (111) and located entirely on the inner side of the transition section (2).

6. The heightening tool according to claim 1, characterized in that: The transition section (2) comprises an upper ring plate (21) for being connected to the wheel hub by bolts, a lower ring plate (22) connected to the elevated base (1) by bolts, a cylindrical body (23) whose upper and lower ends are respectively welded to the upper ring plate (21) and the lower ring plate (22), and a plurality of webs (24) evenly distributed along the circumferential direction, wherein the upper side edge, the lower side edge and the inner side edge of the web (24) are respectively welded to the lower end surface of the upper ring plate (21), the upper end surface of the lower ring plate (22) and the outer side surface of the cylindrical body (23).

7. The heightening tool according to claim 6, characterized in that: The lower ring plate (22) comprises three first sections (221) having straight outer edges and three second sections (222) having arc-shaped outer edges, and the first sections (221) and the second sections (222) are alternately arranged so that the outer edges of the three first sections (221) are respectively flush with the outer edges of the three base brackets (11).

8. The heightening tool according to any one of claims 1 to 7, characterized in that: The lower ring plate (22) is provided with an outer bolt hole (223) and an inner bolt hole (224) respectively located on the outer side and the inner side of the cylindrical body (23); the outer bolt hole (223) and the inner bolt hole (224) are both long round bolt holes extending along the length direction of the angle steel of the frame structure (111) connected thereto.

9. An impeller assembly method, using the heightening tooling according to any one of claims 1 to 8, characterized in that: The steps include: S1: Arrange three base brackets (11) symmetrically to form a heightened base (1); S2: Connect the transition section (2) to the raised base (1) by bolts; S3: Connect the wheel hub to the transition section (2) by means of bolts, so that the three blade mounting holes of the wheel hub correspond to the three base brackets (11) respectively; S4: Assemble components and hub cover in the wheel hub.

10. The impeller assembly method according to claim 9, characterized in that: The following steps are also included: S5: transporting the assembled hub to the wind farm; S6: Connecting the heightened base (1), the transition section (2) and the lengthened bracket (3) at the wind farm to form the heightened tooling as claimed in claim 3 or 4; S7: Install the assembled wheel hub to the transition section (2); S8: hoist the three blades separately and install them to the hub; S9: Dismantle the heightening tooling and lift the assembled impeller as a whole.

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