Method for calculating front wind speed of cabin of wind generating set

Abstract

The invention relates to the field of wind power generation, in particular to a wind generating set cabin front wind speed calculation method, which comprises the following steps of: acquiring wind measurement data of a project location and cabin wind speed of each machine position; selecting a representative machine position according to a selection principle; calculating an anemometer annual wind speed of the anemometer tower, and calculating a representative annual wind speed; representative year judgment is carried out on the current year of the representative camera; correcting the representative annual wind speed of the anemometer tower to the wind speed of the current year; the time sequence of the anemometer tower data is imported into numerical simulation software to be calculated, and the front average wind speed of a cabin of each representative machine position is obtained; establishing a quantitative relationship between the cabin wind speed of each representative aircraft position and the cabin front average wind speed to obtain a transfer function; and calculating the cabin front wind speed through the transfer function. According to the method, the existing early-stage anemometer tower data is used for analysis, so that the post-evaluation working efficiency is improved, and the investment of newly added anemometer equipment is saved.

Description

Technical Field

[0001] The invention relates to the field of wind power generation, and in particular to a method for calculating the wind speed in front of a nacelle of a wind power generator set. Background Art

[0002] After the wind turbine is built, a post-evaluation of the wind power project will be carried out. By processing and analyzing the wind turbine operating data, the operating effects of the wind turbine in the wind farm will be restored and verified, providing experience guidance for subsequent design.

[0003] Normally, the cabin wind speed V used in the post-evaluation is n Generally affected by the impeller, the wind speed is lower than the actual value, resulting in a certain deviation between the wind turbine operation status obtained by this wind speed analysis and the actual situation. In order to obtain the wind speed V in front of the nacelle that is not affected by the impeller, the usual practice is to install a new wind tower or lidar in front of a wind turbine for synchronous observation, or to install a lidar wind measurement device in front of the nacelle. All of the above methods require the installation of new wind measurement equipment, which has the problems of complex installation process, increased investment, and long time consumption. Summary of the invention

[0004] In order to solve the above technical problem, the present invention provides a method for calculating the wind speed in front of a nacelle of a wind turbine generator set.

[0005] The present invention provides a method for calculating the wind speed in front of a nacelle of a wind turbine generator set, which adopts the following technical solution:

[0006] A method for calculating the wind speed in front of a nacelle of a wind turbine generator set, characterized in that it comprises the following steps:

[0007] Obtain wind measurement data at the project site and cabin wind speed at each position;

[0008] According to the selection principle, select representative seats;

[0009] Calculate the annual wind speed measured by the wind tower and the representative annual wind speed;

[0010] Determine the representative year for the current year of the representative aircraft positions;

[0011] Correct the annual wind speed represented by the wind tower to the wind speed of the current year;

[0012] The time series of wind tower data was imported into numerical simulation software for calculation to obtain the average wind speed in front of the cabin of each representative aircraft position;

[0013] Establish a quantitative relationship between the cabin wind speed of each representative aircraft position and the average wind speed in front of the cabin to obtain the transfer function;

[0014] The wind speed in front of the cabin is calculated by the transfer function.

[0015] In a specific feasible implementation plan, the selection principles are as follows: the horizontal distance between the machine site and the wind tower shall not exceed 2km, and the vertical height difference shall not exceed 50m; for mountain wind farms, the machine site and the wind tower shall be located on the same ridge, and there shall be no obvious obstructions around them.

[0016] In a specific embodiment, the wind measurement data includes hourly wind speed and wind direction data for at least one full year;

[0017] Wind data is obtained through wind towers;

[0018] The nacelle wind speed is recorded by the SCADA system installed on the nacelle of the wind turbine.

[0019] In a specific implementation scheme, the method for calculating the annual wind speed of the wind tower is:

[0020] By fitting the wind shear power law index through the wind tower, the hourly wind speed in the wind measurement data is extrapolated to the wind speed when the height is consistent with the hub height of the wind turbine;

[0021] Calculate the average value to obtain the annual wind speed V1 measured by the wind tower for a full year.

[0022] In a specific possible implementation scheme, the method for calculating the representative annual wind speed is:

[0023] Combined with long-sequence reference data, the wind measurement year of the wind tower is judged;

[0024] According to the wind tower wind measurement year, the wind speed V1 of the wind measurement year is corrected to the representative year wind speed V2. The calculation formula is:

[0025]

[0026] In the above formula, V2 represents the annual wind speed;

[0027] VP represents the multi-year average wind speed;

[0028] VP1 represents the average wind speed in the wind measurement year.

[0029] In a specific feasible implementation plan, the basis for judging the wind measurement year of the wind tower in combination with the long sequence reference data is:

[0030] If the deviation between the average wind speed VP1 of the long-sequence reference data in the wind measurement year and the multi-year average wind speed VP is less than or equal to 2%, it indicates that the wind measurement year of the wind tower is a year of average wind;

[0031] If the average wind speed VP1 of the long-series reference data in the wind measurement year is more than 2% higher than the average wind speed VP of many years, it indicates that the wind measurement year of the wind tower is a strong wind year;

[0032] If the average wind speed VP1 of the long-series reference data in the wind measurement year is more than 2% smaller than the average wind speed VP of many years, it indicates that the wind measurement year of the wind tower is a year with low wind.

[0033] In a specific implementation scheme, the calculation formula for the average wind speed in front of the nacelle is:

[0034]

[0035] In the above formula, M is the total number of representative seats;

[0036] i represents the i-th representative camera position, i=1,2,…,M;

[0037] is the average wind speed in front of the nacelle;

[0038] V m is the wind speed in front of the nacelle.

[0039] In a specific feasible implementation plan, a quantitative relationship is established between the cabin wind speed of each representative aircraft position and the average wind speed in front of the cabin, and a method for obtaining a transfer function is as follows:

[0040] Calculate the average wind speed in the computer cabin;

[0041] Calculate the multiplication factor based on the average wind speed in the cabin and the average wind speed in front of the cabin;

[0042] Construct the transfer function based on the multiplication coefficients.

[0043] In a specific embodiment, the calculation formula of the rate coefficient is:

[0044]

[0045] In the above formula, σ is the multiplication factor;

[0046] is the average wind speed in the cabin;

[0047] is the average wind speed in front of the nacelle.

[0048] In a specific implementation scheme, the transfer function is: j =σV j '

[0049] In the above formula, V j represents the wind speed in front of the cabin at the jth position, V j ′ represents the cabin wind speed at the jth aircraft position.

[0050] In summary, the present invention has the following beneficial effects:

[0051] By using the measured wind tower data around the built wind turbines, the wind speed in front of the nacelle of the built wind turbines is obtained through data processing, numerical simulation calculation and other methods, and a transfer function is established with the wind speed in the nacelle of the wind turbines. The nacelle wind speed transfer function can be accurately calculated, providing a better data basis for power curve verification and unit operation status judgment in the post-evaluation of wind power projects. At the same time, the use of existing early wind tower data for analysis improves the efficiency of post-evaluation work and saves investment in new wind measurement equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 It is a flow chart of the method for calculating the wind speed in front of the nacelle of a wind turbine generator set.

[0053] Figure 2 This is a schematic diagram showing the camera layout. DETAILED DESCRIPTION

[0054] The following combination Figure 1-Figure 2 The present invention is described in further detail.

[0055] Reference Figure 1 , the method for calculating the wind speed in front of the nacelle of a wind turbine generator set includes the following steps:

[0056] S100, obtaining wind measurement data at the project site and cabin wind speed at each machine position.

[0057] The wind measurement data includes hourly wind speed and direction data for at least one full year at the project site, and the wind measurement data is obtained through the wind tower at the project site. The nacelle wind speed is recorded by the SCADA system installed on the nacelle of the wind turbine.

[0058] S200, select a representative camera position according to the selection principle.

[0059] The specific selection principles are: the horizontal distance between the machine site and the wind tower shall not exceed 2km, and the vertical height difference shall not exceed 50m; for mountain wind farms, the machine site and the wind tower shall be located on the same ridge, and there shall be no obvious obstructions around them.

[0060] For ease of understanding, combined Figure 2 Further explanation. There is a camera position 1 at the wind tower, and camera positions 2 to 8 are distributed around camera position 1. Camera positions 8, camera position 2 and camera position 5 are located on the same ridge as the wind tower and are relatively close to the wind tower. After further analysis, camera position 5 is far away from the wind tower; although camera position 2 is relatively close to the wind tower, the altitude is significantly lower; camera position 8 is close to the wind tower and the altitude is similar. Therefore, camera positions 1 and 8 are more representative and are selected as representative camera positions.

[0061] S300. Calculate the annual wind speed V1 of the anemometer tower and the representative annual wind speed V2.

[0062] Use the anemometer tower to fit the wind shear power law exponent, and extrapolate the hourly wind speed in the anemometer data to the wind speed at the same height as the wind turbine hub height. By calculating the average value, the annual wind speed V1 of the anemometer tower for a complete year can be further obtained. Combine long-term reference data such as meteorological station data or mesoscale data to judge the anemometer tower's measurement year. The anemometer tower's measurement year is specifically a high-wind year, a normal-wind year, or a low-wind year. Specifically:

[0063] If the deviation between the average wind speed VP1 of the long-term reference data in the measurement year and the multi-year average wind speed VP is less than or equal to 2%, that is it indicates that the anemometer tower's measurement year is a normal-wind year;

[0064] If the average wind speed VP1 of the long-term reference data in the measurement year is more than 2% larger than the multi-year average wind speed VP, that is VP1 > VP, and it indicates that the anemometer tower's measurement year is a high-wind year;

[0065] If the average wind speed VP1 of the long-term reference data in the measurement year is more than 2% smaller than the multi-year average wind speed VP, that is VP1 < VP, and it indicates that the anemometer tower's measurement year is a low-wind year.

[0066] Revise the annual wind speed V1 of the measurement year according to the anemometer tower's measurement year to obtain the representative annual wind speed V2. The revision method can adopt the proportional revision method or the sector-by-sector revision method. For the sake of easy understanding, the proportional revision method is used for elaboration.

[0067] Revise the annual wind speed V1 of the measurement year according to the ratio of the difference between the average wind speed VP1 of the long-term reference data in the measurement year and the multi-year average wind speed VP to the multi-year average wind speed VP. The calculation formula is as follows:

[0068]

[0069] Thus, the representative annual wind speed V2 is obtained.

[0070] S400. Judge the representative year of the anemometer tower for the current year of the representative location.

[0071] Combine long-term reference data such as meteorological station data or mesoscale data to judge the representative year of the current year.

[0072] S500. Revise the representative annual wind speed V2 of the anemometer tower to the wind speed V3 of the current year.

[0073] Use the proportional revision method or the sector-by-sector revision method to revise the representative annual wind speed V2 to the wind speed V3 of the current year. The calculation method is the same as that in step S300 and will not be elaborated here.

[0074] S600, import the time series of wind tower data V3 into numerical simulation software for calculation to obtain the average wind speed V in front of the cabin of each representative aircraft position.

[0075] Simulate the terrain of the project site, and the simulation modeling can be done by CFD flow field simulation, etc. Substitute the time series of the wind speed V3 of the current year into the model for calculation to obtain the wind speed V in front of the cabin of the representative position. m The wind speed V in front of the nacelle passing through the representative aircraft position m Average wind speed in front of computer cabin The calculation formula is as follows:

[0076]

[0077] In the above formula, M is the total number of representative camera positions, i represents the i-th representative camera position, and i=1,2,…,M.

[0078] The example in step S200 is used for further explanation:

[0079] Substituting the time series of wind speed V3 in the current year into the model for calculation, we can get the wind speed in front of the cabin at stand 1 as V m1 , the wind speed in front of the cabin at station 8 is V m8 Average wind speed in front of the nacelle

[0080] S700: Establish a quantitative relationship between the cabin wind speed of each representative aircraft position and the average wind speed V in front of the cabin to obtain a transfer function NTF.

[0081] Calculate the average cabin wind speed based on the cabin wind speed at the representative aircraft position According to the average wind speed in the cabin and the average wind speed in front of the nacelle Calculate the multiplication factor σ.

[0082] The calculation formula of the multiplication factor σ is:

[0083] We can further construct the transfer function NTF: V j =σV j '

[0084] In the above formula, V j represents the wind speed in front of the cabin at the jth position, V j ′ represents the nacelle wind speed at the jth position. Through the transfer function NTF, the wind speed in front of the nacelle can be calculated by recording the nacelle wind speed obtained by the SCADA system installed on the nacelle of the wind turbine generator without setting up an additional wind tower.

[0085] The above are all preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention. Therefore, any equivalent changes made based on the structure, shape, and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for calculating the wind speed in front of a nacelle of a wind turbine generator set, characterized in that: The steps include: Obtain wind measurement data at the project site and cabin wind speed at each position; According to the selection principle, select representative seats; Calculate the annual wind speed measured by the wind tower and the representative annual wind speed; Determine the representative year for the current year of the representative aircraft positions; Correct the annual wind speed represented by the wind tower to the wind speed of the current year; The time series of wind tower data was imported into numerical simulation software for calculation to obtain the average wind speed in front of the cabin of each representative aircraft position; Establish a quantitative relationship between the cabin wind speed of each representative aircraft position and the average wind speed in front of the cabin to obtain the transfer function; The wind speed in front of the cabin is calculated by the transfer function.

2. The method for calculating the wind speed in front of the nacelle of a wind turbine generator set according to claim 1, characterized in that: The specific selection principles are: the horizontal distance between the machine site and the wind tower shall not exceed 2km, and the vertical height difference shall not exceed 50m; for mountain wind farms, the machine site and the wind tower shall be located on the same ridge, and there shall be no obvious obstructions around them.

3. The method for calculating the wind speed in front of the nacelle of a wind turbine generator set according to claim 1, characterized in that: Wind data include hourly wind speed and direction data for at least one full year; Wind data is obtained through wind towers; The nacelle wind speed is recorded by the SCADA system installed on the nacelle of the wind turbine.

4. The method for calculating the wind speed in front of the nacelle of a wind turbine generator set according to claim 1, characterized in that: The method for calculating the annual wind speed of the wind tower is: By fitting the wind shear power law index through the wind tower, the hourly wind speed in the wind measurement data is extrapolated to the wind speed when the height is consistent with the hub height of the wind turbine; Calculate the average value to obtain the annual wind speed V1 measured by the wind tower for a full year.

5. The method for calculating the wind speed in front of the nacelle of a wind turbine generator set according to claim 4, characterized in that: The method for calculating the representative annual wind speed is: Combined with long-sequence reference data, the wind measurement year of the wind tower is judged; According to the wind tower wind measurement year, the wind speed V1 of the wind measurement year is corrected to the representative year wind speed V2. The calculation formula is: In the above formula, V2 represents the annual wind speed; VP represents the multi-year average wind speed; VP1 represents the average wind speed in the wind measurement year.

6. The method for calculating the wind speed in front of the nacelle of a wind turbine generator set according to claim 5, characterized in that: The basis for judging the wind measurement year of the wind tower in combination with the long sequence reference data is: If the deviation between the average wind speed VP1 of the long-sequence reference data in the wind measurement year and the multi-year average wind speed VP is less than or equal to 2%, it indicates that the wind measurement year of the wind tower is a year of average wind; If the average wind speed VP1 of the long-series reference data in the wind measurement year is more than 2% higher than the average wind speed VP of many years, it indicates that the wind measurement year of the wind tower is a strong wind year; If the average wind speed VP1 of the long-series reference data in the wind measurement year is more than 2% smaller than the average wind speed VP of many years, it indicates that the wind measurement year of the wind tower is a year with low wind.

7. The method for calculating the wind speed in front of the nacelle of a wind turbine generator set according to claim 1, characterized in that: The calculation formula for the average wind speed in front of the nacelle is: In the above formula, M is the total number of representative seats; i represents the i-th representative camera position, i=1,2,…,M; is the average wind speed in front of the nacelle; V m is the wind speed in front of the nacelle.

8. The method for calculating the wind speed in front of the nacelle of a wind turbine generator set according to claim 1, characterized in that: The method of establishing a quantitative relationship between the cabin wind speed of each representative position and the average wind speed in front of the cabin to obtain the transfer function is: Calculate the average wind speed in the computer cabin; Calculate the multiplication factor based on the average wind speed in the cabin and the average wind speed in front of the cabin; Construct the transfer function based on the multiplication coefficients.

9. The method for calculating the wind speed in front of the nacelle of a wind turbine generator set according to claim 8, characterized in that: The calculation formula of the multiplication factor is: In the above formula, σ is the multiplication factor; is the average wind speed in the cabin; is the average wind speed in front of the nacelle.

10. The method for calculating the wind speed in front of the nacelle of a wind turbine generator set according to claim 9, characterized in that: The transfer function is: V j =σV′ j In the above formula, V j represents the wind speed in front of the cabin at the jth position, V′ j represents the cabin wind speed at the j-th aircraft position.

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