CN109973321B - Tower door opening and tower of wind generating set and wind generating set - Google Patents
Tower door opening and tower of wind generating set and wind generating set Download PDFInfo
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- CN109973321B CN109973321B CN201711445775.XA CN201711445775A CN109973321B CN 109973321 B CN109973321 B CN 109973321B CN 201711445775 A CN201711445775 A CN 201711445775A CN 109973321 B CN109973321 B CN 109973321B
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
- F03D—WIND MOTORS
- F03D13/00—Assembly, mounting or commissioning of wind motors; Arrangements specially adapted for transporting wind motor components
- F03D13/20—Arrangements for mounting or supporting wind motors; Masts or towers for wind motors
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
- F03D—WIND MOTORS
- F03D80/00—Details, components or accessories not provided for in groups F03D1/00 - F03D17/00
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/70—Wind energy
- Y02E10/72—Wind turbines with rotation axis in wind direction
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/70—Wind energy
- Y02E10/728—Onshore wind turbines
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
- Y02P70/50—Manufacturing or production processes characterised by the final manufactured product
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- Sustainable Development (AREA)
- Sustainable Energy (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Wind Motors (AREA)
Abstract
The invention provides a tower frame door opening of a wind generating set, a tower frame and the wind generating set. The tower door opening of the wind generating set comprises arc-shaped parts which are symmetrical up and down, and the arc-shaped parts meet the following formula: (x/a)m+(y/b)n1, wherein X and Y represent coordinate values of any point on the arc part on an X axis and a Y axis respectively, a represents 1/2 value of the width of the arc part on the X axis, and b represents a height value of the arc part on the Y axis; and m and n respectively satisfy: m is more than or equal to 1.65 and less than or equal to 1.80, and n is more than or equal to 1.65 and less than or equal to 1.80. The tower door opening, the tower and the wind generating set of the wind generating set can effectively reduce the stress concentration coefficient of the tower door opening and reduce the thickness of the tower at the position of the tower door opening, thereby reducing the weight of the tower and reducing the manufacturing cost.
Description
Technical Field
The invention relates to the technical field of wind power generation, in particular to a tower door opening of a wind generating set, a tower comprising the tower door opening and the wind generating set, wherein the tower door opening can reduce the stress concentration coefficient of the tower door opening.
Background
A door opening arranged at the bottom of the tower frame of the wind generating set is a main channel for maintenance operators and equipment to enter the fan. Due to the opening of the tower door opening, the tower has a phenomenon of local stress increase (stress concentration). The stress concentration can cause fatigue cracks on the object and also can cause static load fracture of parts made of brittle materials. In engineering, the stress Concentration factor SCF (stress Concentration factor) is used to represent the degree of stress Concentration, and the SCF value can be calculated by dividing the maximum stress at which stress Concentration occurs by the average stress, and is greater than 1. Engineering experience shows that the more drastic the change in cross-sectional dimension, the greater the SCF value.
Therefore, holes or grooves with sharp corners are avoided as much as possible when designing the tower frame door opening, and circular arc transition is needed for designing the opening. From the manufacturing process, the existing door opening cutting method adopts a numerical control cutting machine to directly cut a cylinder. The method avoids the trouble that the coordinates of the tower frame door opening shape need to be transformed when the method of firstly cutting the steel plate and then rolling the steel plate into the cylinder is adopted. In the operation of the numerically controlled cutting machine, the cutting machine can read the coordinates of the points and process them to obtain the shape adopted by the design, by taking only enough coordinate points on the curve projected onto the XOY plane (i.e., the front view). Therefore, in actual production, as long as the cutting shape function of the tower door opening can be obtained, enough points can be obtained, and the required shape can be obtained through processing.
In the conventional tower door opening design, the upper and lower end portions of the door opening are generally designed to be oval in front view (see fig. 1). However, the SCF value near the tower door opening designed according to the ellipse is still large, which can generally reach 1.40 to 1.50, and since the sensitivity of the tower wall thickness to the SCF value is large, in order to make the tower design meet the strength requirement, the existing ellipse design still needs to thicken the tower wall thickness at the tower door opening part, resulting in the tower having a large mass.
Considering that the magnitude of the SCF value directly affects the magnitude of the wall thickness of the tower at the tower door opening, there is a need to design a tower door opening that can reduce the SCF value at the current state of the art to reduce the wall thickness and weight of the tower.
Disclosure of Invention
In order to solve the technical problem, the invention provides the tower door opening of the wind generating set, which can reduce the SCF value of the tower door opening and reduce the thickness of the tower at the position of the door opening.
According to an aspect of the invention, a tower door opening of a wind generating set is provided, the tower door opening of the wind generating set comprises arc-shaped parts which are symmetrical up and down, and the arc-shaped parts satisfy the following formula:
wherein X and Y represent coordinate values of any point on the arc part on the X axis and the Y axis respectively, a represents 1/2 value of the width of the arc part on the X axis, and b represents height value of the arc part on the Y axis; and m and n respectively satisfy: m is more than or equal to 1.65 and less than or equal to 1.80, and n is more than or equal to 1.65 and less than or equal to 1.80, so as to reduce the stress concentration coefficient of the tower door opening.
According to an exemplary embodiment of the present invention, in the formula that the arc portion satisfies, m and n are respectively: and m is 1.70, and n is 1.69, so that the stress concentration coefficient of the tower door opening is reduced to a greater extent.
According to an exemplary embodiment of the present invention, a straight line is disposed between the upper and lower arc-shaped portions of the tower door opening to meet the design requirement of the size of the tower door opening.
According to another aspect of the invention, a tower for a wind power plant is provided, comprising a tower door opening as described above.
According to another aspect of the invention, there is provided a wind park comprising a tower as described above.
The tower door opening, the tower and the wind generating set of the wind generating set can effectively reduce the SCF value of the tower door opening and reduce the thickness of the tower at the position of the door opening, thereby reducing the weight of the tower and reducing the manufacturing cost.
Drawings
The above and other features and advantages of the present invention will become more apparent from the following detailed description of exemplary embodiments thereof, taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a diagram showing an elliptic function curve;
FIG. 2 is a diagram illustrating a hyperelliptic function curve according to an exemplary embodiment of the present invention;
FIG. 3 is a partial view schematically illustrating a tower including a tower door opening of a super-elliptical design, according to an exemplary embodiment of the present invention;
FIG. 4 is a schematic diagram illustrating a tower door opening shape of a hyperelliptical design in accordance with an exemplary embodiment of the present invention;
FIG. 5 is a stress cloud when an axial force Fz is applied to the tower door opening of the hyperelliptical design shown in FIG. 4;
FIG. 6 is a stress cloud when a bending moment Mxy is applied to the tower door opening of the hyperelliptical design shown in FIG. 4;
FIG. 7 is a schematic illustration of a prior art elliptical design tower door opening shape;
FIG. 8 is a stress cloud when an axial force Fz is applied to the elliptically designed tower door opening shown in FIG. 7; and
FIG. 9 is a stress cloud when a bending moment Mxy is applied to the elliptically designed tower door opening shown in FIG. 7.
The reference numbers illustrate:
1: a tower; 10: a tower door opening; 11: an upper arcuate portion; 12: a lower arcuate portion; 13: a straight line segment.
Detailed Description
Embodiments of the present invention will now be described more fully with reference to the accompanying drawings, in which exemplary embodiments of the invention are shown.
According to the invention, the shape of the door opening in the bottom tower 1 of the wind generating set is optimized, so that the stress is as small as possible, and the purpose of reducing the SCF value is achieved. According to an exemplary embodiment of the invention, a tower door opening 10 of a wind generating set and a tower comprising the tower door opening 10 are provided, and a wind generating set comprising the tower door opening 10 is also provided.
The tower door opening 10 according to an exemplary embodiment of the present invention includes arc parts 11 and 12 that are symmetrical up and down, and the arc parts 11 and 12 satisfy the following formula (1):
wherein X and Y represent coordinate values of any point on the arc parts 11 and 12 on the X and Y axes, respectively, a represents 1/2 value of the width of the arc parts 11 and 12 on the X axis, and b represents height value of the arc parts 11 and 12 on the Y axis; and m and n respectively satisfy: m is more than or equal to 1.65 and less than or equal to 1.80, and n is more than or equal to 1.65 and less than or equal to 1.80.
Here, a rectangular coordinate system XOY is established with the center O of the tower door opening 10 of the wind turbine generator system as an origin, and a horizontal axis and a vertical axis are defined as an X axis and a Y axis, respectively, where m and n are positive numbers.
Here, the expression (1) is referred to as a hyperelliptic function expression. As shown in fig. 3, the hyperelliptic function is a new shape function proposed based on an elliptic function, and a family of curves including an ellipse can be drawn by two variables m and n. A curve drawn according to a hyperelliptic function is called a hyperelliptic curve. When m is 2, the hyperelliptic curve is degenerated into an elliptic curve; when m is equal to n is equal to 1, the hyperelliptic curve is degenerated into a straight line. Due to the introduction of the variables m and n, the range of the design domain is enlarged, and therefore, in the shape optimization process, the purpose of reducing the SCF value is achieved by setting proper values of m and n.
M and n satisfy: when m is more than or equal to 1.65 and less than or equal to 1.80 and n is more than or equal to 1.65 and less than or equal to 1.80, the tower door opening designed according to the shape function formula (1) can effectively reduce the stress concentration coefficient SCF, thereby reducing the thickness of the tower at the position of the tower door opening, reducing the total weight of the tower and lowering the production cost.
If m and n are outside the above range, the above effect cannot be achieved. In detail, in the case where m and n are less than 1.65, the shape of the tower door opening tends to be a rhombus, so that the tower door opening has a sharp corner, so that the stress concentration coefficient SCF of the corresponding position becomes large, resulting in an increase in the wall thickness of the tower at the corresponding position, an increase in the overall weight of the tower, and an increase in the production cost. In the case where m and n are larger than 1.80, the shape of the tower door opening approaches a rectangle having corners, so that the stress concentration coefficient SCF becomes large at the corresponding location, resulting in an increase in the wall thickness of the tower at the corresponding location, an increase in the overall weight of the tower, and an increase in the production cost.
According to an exemplary embodiment of the present invention, a straight line section 13 is disposed between the upper and lower arc sections 11 and 12 of the tower door opening 10, the height of the straight line section 13 in the Y axis is 2h, the straight line section 13 is symmetrical about the X axis, and the upper arc section 11 and the lower arc section 12 satisfy the following equations (2) and (3), respectively:
wherein X and Y represent coordinate values of any point on the arc parts 11 and 12 on the X and Y axes, respectively, a represents 1/2 value of the width of the arc parts 11 and 12 on the X axis, b represents height value of the arc parts 11 and 12 on the Y axis, and h represents 1/2 value of the height of the straight line part 13 on the Y axis; and m and n respectively satisfy: m is more than or equal to 1.65 and less than or equal to 1.80, and n is more than or equal to 1.65 and less than or equal to 1.80.
The purpose of the straight section 13 is here primarily to allow the relevant equipment to pass smoothly through the tower door opening 10 without touching the door opening, so that the design requirements for the size of the door opening can be met by adjusting the height of the straight section 13 according to the actual needs.
As an example, if the height (2b +2h) of the tower door opening 10 on the Y axis is 4000mm, the width (2a) of the tower door opening 10 on the X axis is 1700mm, the height (2h) of the straight line segment 13 on the Y axis is 1100mm, and the height (b) of the arc portions 11 and 12 on the Y axis is 1450mm, the upper arc portion 11 and the lower arc portion 12 satisfy the following formula (4) and formula (5), respectively:
using the parameters of the tower door opening 10 described above, a tower door opening designed using a hyperelliptic function according to the present invention is compared to an existing tower door opening designed using a standard elliptic function. Specifically, the shape of the tower door opening according to the present invention is designed by a hyper elliptic function equation where m is 1.70 and n is 1.69, and the existing shape of the tower door opening is designed by a standard elliptic function equation (m is 2 and n is 2).
Table 1 below shows the dimensions of the tower door opening and the nominal stress calculation results, and Table 2 below shows the SCF calculation results of the tower door opening designed by the hyperelliptic function according to the present invention and the existing tower door opening designed by the standard elliptic function.
TABLE 1
TABLE 2
Referring to fig. 5 and 6, as compared with fig. 8 and 9, respectively, and by combining the calculation results shown in table 2, it can be seen that when m is 1.70 and n is 1.69, the maximum stress concentration coefficient SCF of the tower door opening designed by the hyperelliptic function formula according to the present invention is 1.328, and the maximum stress concentration coefficient SCF of the conventional tower door opening designed by the standard elliptic function formula is 1.400. Therefore, compared with the existing tower door opening designed by adopting a standard elliptic function formula, the tower door opening designed by adopting the hyperelliptic function formula reduces the maximum stress concentration coefficient by 5.14 percent. As a result, a super-elliptical shaped tower door opening according to the present invention may be more conducive to reducing the stress concentration factor SCF than a conventional standard elliptical shaped tower door opening. Therefore, under the existing process conditions, the shape of the door opening is optimally designed by adopting the hyperelliptic function, and the SCF value can be effectively reduced, so that the thickness of the tower at the door opening section is reduced, and the effect of reducing the weight of the tower is achieved.
Based on the calculation results shown in table 2, the SCF value of the standard elliptical tower door opening can reach 1.400, and the SCF value of the super elliptical tower door opening according to the present invention can be reduced to 1.328, so that for a tower with a diameter of 7m and a height of 10m, the weight of the tower door opening according to the present invention designed by the super elliptical function formula can be reduced by about 5t, compared to the existing tower door opening designed by the standard elliptical function formula; according to a wind field, 50 wind driven generators are arranged, and each ton of steel plates is quoted by 1 ten thousand yuan, so that about 250 ten thousand yuan can be saved, namely, the tower frame door opening designed by adopting the hyperelliptic function formula can reduce the manufacturing cost by about 250 ten thousand yuan.
The tower door opening, the tower and the wind generating set of the wind generating set can effectively reduce the stress concentration coefficient SCF of the tower door opening and reduce the thickness of the tower at the position of the door opening, thereby reducing the weight of the tower and reducing the manufacturing cost.
While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the following claims.
Claims (5)
1. A tower door opening of a wind power plant, characterized in that the tower door opening (10) of the wind power plant comprises arc-shaped parts (11, 12) which are symmetrical up and down, and the arc-shaped parts (11, 12) satisfy the following formula:
wherein X and Y represent coordinate values of any point on the arc-shaped parts (11 and 12) on the X axis and the Y axis respectively, a represents 1/2 value of the width of the arc-shaped parts (11 and 12) on the X axis, and b represents height value of the arc-shaped parts (11 and 12) on the Y axis; and m, n satisfy:
1.65≤m≤1.80，1.65≤n≤1.80。
2. a tower door opening of a wind park according to claim 1, wherein in the formula fulfilled by the arc-shaped parts (11, 12), m, n are: m is 1.70 and n is 1.69.
3. A tower door opening of a wind power plant according to claim 1 or 2, characterized in that a straight line section (13) is provided between the upper and lower arc-shaped parts (11, 12) of the tower door opening.
4. A tower for a wind park, characterized in that it comprises a tower door opening (10) according to any of claims 1-3.
5. A wind park according to claim 4, wherein the wind park comprises a tower according to claim 4.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201711445775.XA CN109973321B (en) | 2017-12-27 | 2017-12-27 | Tower door opening and tower of wind generating set and wind generating set |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201711445775.XA CN109973321B (en) | 2017-12-27 | 2017-12-27 | Tower door opening and tower of wind generating set and wind generating set |
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| Publication Number | Publication Date |
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| CN109973321A CN109973321A (en) | 2019-07-05 |
| CN109973321B true CN109973321B (en) | 2020-05-05 |
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Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN112648148A (en) * | 2020-12-30 | 2021-04-13 | 华能国际电力股份有限公司江苏清洁能源分公司 | Wind turbine generator, circular tower frame door opening structure of wind turbine generator and manufacturing method |
| CN114987688A (en) * | 2022-06-20 | 2022-09-02 | 中国华能集团清洁能源技术研究院有限公司 | Anchor chain and chain ring thereof and processing device of chain ring |
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| CN102434408A (en) * | 2011-12-23 | 2012-05-02 | 北京金风科创风电设备有限公司 | Wind generating set tower frame door opening and design method thereof |
| DE102012019595B3 (en) * | 2012-10-05 | 2013-11-21 | E.N.O. Energy Systems Gmbh | Opening for providing ventilation in e.g. steel pipe tower of wind energy plant, has reinforcing element provided in support structure, where opening is formed by door and reinforcing element in support structure |
| CN203420838U (en) * | 2013-08-15 | 2014-02-05 | 山西天宝风电法兰有限公司 | Reinforced seamless plate type wind power tower forging elliptic door frame |
| EP3219982A1 (en) * | 2016-03-14 | 2017-09-20 | Siemens Aktiengesellschaft | Door frame of a wind turbine tower |
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2017
- 2017-12-27 CN CN201711445775.XA patent/CN109973321B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201696236U (en) * | 2008-12-04 | 2011-01-05 | 维斯塔斯风力***集团公司 | Tower section and plate slab for same |
| CN102434408A (en) * | 2011-12-23 | 2012-05-02 | 北京金风科创风电设备有限公司 | Wind generating set tower frame door opening and design method thereof |
| DE102012019595B3 (en) * | 2012-10-05 | 2013-11-21 | E.N.O. Energy Systems Gmbh | Opening for providing ventilation in e.g. steel pipe tower of wind energy plant, has reinforcing element provided in support structure, where opening is formed by door and reinforcing element in support structure |
| CN203420838U (en) * | 2013-08-15 | 2014-02-05 | 山西天宝风电法兰有限公司 | Reinforced seamless plate type wind power tower forging elliptic door frame |
| EP3219982A1 (en) * | 2016-03-14 | 2017-09-20 | Siemens Aktiengesellschaft | Door frame of a wind turbine tower |
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