Wind turbine yaw control method and system based on tower load

Abstract

The present invention discloses a wind turbine yaw control method and system based on tower load. First, the tower load is measured and filtered, and then the filtered tower load is processed to obtain a load My representing the tower My direction. Tower and represents the load Mz in the tower Mz direction Tower , then My Tower , Mz Tower The yaw angle A is calculated by performing an inverse tangent, and the yaw angle A is corrected based on different yaw angle ranges multiplied by a correction coefficient. Finally, the corrected yaw angle A is issued as a yaw command. The present invention measures the tower load and gives an accurate yaw command after calculation, thereby avoiding problems such as inaccurate wind direction and failure of the anemometer, and also avoids the problems of expensive laser radar and inapplicability in bad weather, and can also increase power generation and reduce unit load.

Description

Technical Field

[0001] The present invention relates to the technical field of wind power generation, and in particular to a tower load-based wind turbine yaw control method, system, storage medium and computing device. In view of the situation where an anemometer fails during a typhoon, yaw by load can significantly reduce the load on various components of the wind turbine. Background Art

[0002] The existing technology is to use an anemometer to measure wind direction to guide the yaw action of the unit, or to use a laser radar to measure wind direction to guide the yaw action of the wind turbine unit.

[0003] There are the following problems with using anemometers to measure wind direction. For upwind wind turbines, the anemometer is located behind the impeller plane. When the impeller rotates, the blades also drive the air to move, causing the wind direction behind the impeller to be disturbed and not consistent with the wind direction in front of the impeller. This results in a large error between the wind direction measured by the anemometer and the actual wind direction, and this error is difficult to assess, resulting in the inability of the wind turbine to accurately face the wind, resulting in a loss of power generation.

[0004] There are the following problems with using LiDAR to measure wind direction: LiDAR is expensive, not suitable for mass use, and has failure problems in rainy, foggy, snowy and other weather conditions, making it unusable.

[0005] When a typhoon occurs, anemometers and lidars are prone to malfunction, making it impossible for wind turbines to issue yaw commands, causing excessive load on the wind turbines and resulting in accidents. Summary of the invention

[0006] The first purpose of the present invention is to overcome the shortcomings and deficiencies of the prior art and to provide a wind turbine yaw control method based on tower load. By measuring the tower load and giving accurate yaw instructions through calculation, problems such as inaccurate wind direction and failure of anemometers are avoided, as well as the high price of laser radars and their unsuitability in bad weather. The method can also increase power generation and reduce unit load.

[0007] A second object of the present invention is to provide a wind turbine yaw control system based on tower load.

[0008] A third object of the present invention is to provide a storage medium.

[0009] A fourth object of the present invention is to provide a computing device.

[0010] The first object of the present invention is achieved by the following technical solution: A yaw control method of a wind turbine based on tower load, comprising the following steps:

[0011] 1) Measure the tower load, including the front and rear loads Mz at the top of the tower top and lateral load My top And the front and rear loads Mz of the tower bottom btm and lateral load My btm , and the measured tower load is filtered through a sliding average filter;

[0012] 2) Calculate the filtered tower load using the following formula to obtain the load My representing the tower in the direction My: Tower and represents the load Mz in the tower Mz direction Tower :

[0013] My Tower = Filter My btm -FilterMy top

[0014] Mz Tower = Filter Mz btm -Filter Mz top

[0015] In the formula, filter My btm Represents the load in the direction of the tower bottom My after filtering, filtered My top represents the load in the direction of My at the top of the tower after filtering, so My Tower The load on the tower My direction is pure tower load, excluding the wind turbine host; filter Mz btm Represents the load in the Mz direction at the bottom of the tower after filtering, and the filtered Mz top represents the load in the Mz direction of the tower top after filtering, so Mz Tower The load on the tower in the Mz direction is purely on the tower, excluding the main engine of the wind turbine;

[0016] 3) My Tower , Mz Tower The yaw angle A is calculated by taking the inverse tangent, and the formula is as follows:

[0017] A=arctan(My Tower / Mz Tower )

[0018] 4) Correcting the yaw angle A by multiplying different yaw angle ranges by a correction coefficient, wherein the larger the yaw angle range, the smaller the correction coefficient;

[0019] 5) The corrected yaw angle A is issued as a yaw command.

[0020] Furthermore, in step 1), four strain gauges are installed at the bottom and top of the tower, one every 90°, to measure the front and rear loads Mz at the top of the tower. topand lateral load My top And the front and rear loads Mz of the tower bottom btm and lateral load My btm , the formula is as follows:

[0021] Mz top =Sttx·sind([Az_nac]-a)+Stty·cosd([Az_nac]-a)

[0022] My top =Sttx·cosd([Az_nac]-a)-Stty·sind([Az_nac]-a)

[0023] Mz btm =Stx·sind([Az_nac]-b)+Sty·cosd([Az_nac]-b)

[0024] My btm =Stx·cosd([Az_nac]-b)-Sty·sind([Az_nac]-b)

[0025] Wherein, Sttx is the load in the X-axis direction measured by the strain gauge at the top of the tower; Stty is the load in the Y-axis direction measured by the strain gauge at the top of the tower; Stx is the load in the X-axis direction measured by the strain gauge at the bottom of the tower; Sty is the load in the Y-axis direction measured by the strain gauge at the bottom of the tower; Az_nac is the nacelle azimuth output by the main control of the wind turbine; a is the nacelle azimuth corresponding to the trough of Sty; b is the nacelle azimuth corresponding to the trough of Sty.

[0026] Further, in step 5), when the yaw error of the wind turbine set is greater than ±5°, the yaw is started; when the yaw error of the wind turbine set is less than 2°, the yaw is stopped; and more than 10 seconds after the yaw is stopped, yaw is allowed again.

[0027] The second object of the present invention is achieved by the following technical solution: a wind turbine yaw control system based on tower load, comprising:

[0028] Tower load measurement module, used to measure tower loads, including the front and rear loads Mz at the top of the tower top and lateral load My top And the front and rear loads Mz of the tower bottom btm and lateral load My btm , and the measured tower load is filtered through a sliding average filter;

[0029] The first calculation module is used to calculate the filtered tower load using the following formula to obtain the load My representing the tower My direction: Tower and represents the load Mz in the tower Mz direction Tower :

[0030] My Tower = Filter My btm -FilterMy top

[0031] Mz Tower = Filter Mz btm -Filter Mz top

[0032] In the formula, filter My btm Represents the load in the direction of the tower bottom My after filtering, filtered My top represents the load in the direction of My at the top of the tower after filtering, so My Tower The load on the tower My direction is pure tower load, excluding the wind turbine host; filter Mz btm Represents the load in the Mz direction at the bottom of the tower after filtering, and the filtered Mz top represents the load in the Mz direction of the tower top after filtering, so Mz Tower The load on the tower in the Mz direction is purely on the tower, excluding the main engine of the wind turbine;

[0033] The second calculation module is used to calculate the My calculated by the first calculation module Tower , Mz Tower The yaw angle A is calculated by taking the inverse tangent, and the formula is as follows:

[0034] A=arctan(My Tower / Mz Tower )

[0035] A yaw angle correction module, used to correct the yaw angle A calculated by the second calculation module, based on different yaw angle ranges multiplied by a correction coefficient, wherein the larger the yaw angle range, the smaller the correction coefficient;

[0036] The yaw instruction issuing module is used to issue a yaw instruction based on the yaw angle A corrected by the yaw angle correction module.

[0037] Furthermore, for the tower load measurement module, four strain gauges need to be installed at the bottom and top of the tower, one every 90°, to measure the front and rear loads Mz at the top of the tower. top and lateral load My top And the front and rear loads Mz of the tower bottom btm and lateral load My btm , the formula is as follows:

[0038] Mz top =Sttx·sind([Az_nac]-a)+Stty·cosd([Az_nac]-a)

[0039] My top =Sttx·cosd([Az_nac]-a)-Stty·sind([Az_nac]-a)

[0040] Mz btm =Stx·sind([Az_nac]-b)+Sty·cosd([Az_nac]-b)

[0041] My btm =Stx·cosd([Az_nac]-b)-Sty·sind([Az_nac]-b)

[0042] Wherein, Sttx is the load in the X-axis direction measured by the strain gauge at the top of the tower; Stty is the load in the Y-axis direction measured by the strain gauge at the top of the tower; Stx is the load in the X-axis direction measured by the strain gauge at the bottom of the tower; Sty is the load in the Y-axis direction measured by the strain gauge at the bottom of the tower; Az_nac is the nacelle azimuth output by the main control of the wind turbine; a is the nacelle azimuth corresponding to the trough of Sty; b is the nacelle azimuth corresponding to the trough of Sty.

[0043] Furthermore, for the yaw command issuing module, when the yaw error of the wind turbine is greater than ±5°, the yaw is started; when the yaw error of the wind turbine is less than 2°, the yaw is stopped; and yaw is allowed to resume after more than 10s of stopping yaw.

[0044] The third object of the present invention is achieved through the following technical solution: a storage medium stores a program, and when the program is executed by a processor, the above-mentioned wind turbine yaw control method based on tower load is implemented.

[0045] The fourth objective of the present invention is achieved through the following technical solution: a computing device, comprising a processor and a memory for storing a program executable by the processor, wherein when the processor executes the program stored in the memory, the above-mentioned tower load-based wind turbine yaw control method is implemented.

[0046] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0047] 1. The present invention can better replace traditional anemometers and expensive laser radars to identify wind direction and issue yaw commands. Its accuracy is within ±5°, which is much higher than the wind direction identified by anemometers. Its price is much lower than that of laser radars, and its applicability is also higher than that of laser radars.

[0048] 2. The present invention can achieve more precise yaw, reduce unnecessary yaw movements, reduce fatigue load on yaw bearings, increase unit life, increase power generation, improve profitability, reduce unit limit load, and avoid accidents caused by excessive unit load. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 Schematic diagram of the wind turbine tower coordinate system of Example 1.

[0050] Figure 2 This is a diagram of the simulation results of the method of the present invention in Example 1.

[0051] Figure 3 This is a system architecture diagram of the present invention according to Example 2. DETAILED DESCRIPTION

[0052] The present invention is further described in detail below in conjunction with embodiments and drawings, but the embodiments of the present invention are not limited thereto.

[0053] Example 1

[0054] This embodiment discloses a yaw control method for a wind turbine generator system based on tower load, the details of which are as follows:

[0055] 1) Measure the tower load, including the front and rear loads Mz at the top of the tower top and lateral load My top And the front and rear loads Mz of the tower bottom btm and lateral load My btm , and the measured tower load is filtered through a sliding average filter;

[0056] Among them, 4 strain gauges are installed at the bottom and top of the tower, one every 90°, to measure the front and rear loads Mz at the top of the tower. top and lateral load My top And the front and rear loads Mz of the tower bottom btm and lateral load My btm , the formula is as follows:

[0057] Mz top =Sttx·sind([Az_nac]-a)+Stty·cosd([Az_nac]-a)

[0058] My top =Sttx·cosd([Az_nac]-a)-Stty·sind([Az_nac]-a)

[0059] Mz btm =Stx·sind([Az_nac]-b)+Sty·cosd([Az_nac]-b)

[0060] My btm =Stx·cosd([Az_nac]-b)-Sty·sind([Az_nac]-b)

[0061] Wherein, Sttx is the load in the X-axis direction measured by the strain gauge at the top of the tower; Sty is the load in the Y-axis direction measured by the strain gauge at the top of the tower; Stx is the load in the X-axis direction measured by the strain gauge at the bottom of the tower; Sty is the load in the Y-axis direction measured by the strain gauge at the bottom of the tower; Az_nac is the nacelle azimuth output by the main control of the wind turbine; a is the nacelle azimuth corresponding to the trough of Sty; b is the nacelle azimuth corresponding to the trough of Sty; the wind turbine tower coordinate system can be found in Figure 1 shown.

[0062] 2) Calculate the filtered tower load using the following formula to obtain the load My representing the tower in the direction My: Tower and represents the load Mz in the tower Mz direction Tower :

[0063] My Tower = Filter My btm -FilterMy top

[0064] Mz Tower = Filter Mz btm -Filter Mz top

[0065] In the formula, filter My btm Represents the load in the direction of the tower bottom My after filtering, filtered My top represents the load in the direction of My at the top of the tower after filtering, so My Tower The load on the tower My direction is pure tower load, excluding the wind turbine host; filter Mz btm Represents the load in the Mz direction at the bottom of the tower after filtering, and the filtered Mz top represents the load in the Mz direction of the tower top after filtering, so Mz Tower The load on the tower in the Mz direction is purely on the tower, excluding the main engine of the wind turbine;

[0066] 3) My Tower , Mz Tower The yaw angle A is calculated by taking the inverse tangent, and the formula is as follows:

[0067] A=arctan(My Tower / Mz Tower )

[0068] 4) Correcting the yaw angle A by multiplying different yaw angle ranges by a correction coefficient, wherein the larger the yaw angle range, the smaller the correction coefficient;

[0069] 5) The corrected yaw angle A is issued as a yaw command. When the yaw error of the wind turbine is greater than ±5°, the yaw is started. When the yaw error of the wind turbine is less than 2°, the yaw is stopped. Yaw is allowed again after more than 10s of stopping yaw.

[0070] According to the above logic, Bladed simulation is performed. Figure 2 is the simulation result, where line 1 is the north wind direction (°), line 2 is the wind speed (m / s), line 3 is the yaw error (°), and line 4 is the yaw command calculated based on the tower load (°). Figure 2 It can be seen that the yaw command calculated based on the tower load is basically consistent with the yaw error, and the unit can yaw according to the yaw command calculated based on the tower load.

[0071] Example 2

[0072] This embodiment discloses a wind turbine yaw control system based on tower load, see Figure 3 As shown, the system includes the following functional modules:

[0073] Tower load measurement module, used to measure tower loads, including the front and rear loads Mz at the top of the tower top and lateral load My top And the front and rear loads Mz of the tower bottom btm and lateral load My btm , and the measured tower load is filtered through a sliding average filter;

[0074] The first calculation module is used to calculate the filtered tower load using the following formula to obtain the load My representing the tower My direction: Tower and represents the load Mz in the tower Mz direction Tower :

[0075] My Tower = Filter My btm -FilterMy top

[0076] Mz Tower = Filter Mz btm -Filter Mz top

[0077] In the formula, filter My btm Represents the load in the direction of the tower bottom My after filtering, filtered My top represents the load in the direction of My at the top of the tower after filtering, so My Tower The load on the tower My direction is pure tower load, excluding the wind turbine host; filter Mz btm Represents the load in the Mz direction at the bottom of the tower after filtering, and the filtered Mz toprepresents the load in the Mz direction of the tower top after filtering, so Mz Tower The load on the tower in the Mz direction is purely on the tower, excluding the main engine of the wind turbine;

[0078] The second calculation module is used to calculate the My calculated by the first calculation module Tower , Mz Tower The yaw angle A is calculated by taking the inverse tangent, and the formula is as follows:

[0079] A=arctan(My Tower / Mz Tower )

[0080] A yaw angle correction module, used to correct the yaw angle A calculated by the second calculation module, based on different yaw angle ranges multiplied by a correction coefficient, wherein the larger the yaw angle range, the smaller the correction coefficient;

[0081] The yaw command issuing module is used to issue the yaw command based on the yaw angle A corrected by the yaw angle correction module. When the yaw error of the wind turbine is greater than ±5°, the yaw is started. When the yaw error of the wind turbine is less than 2°, the yaw is stopped. Yaw is allowed again after more than 10s of stopping yaw.

[0082] Specifically, for the tower load measurement module, four strain gauges need to be installed at the bottom and top of the tower, one every 90°, to measure the front and rear loads Mz at the top of the tower. top and lateral load My top And the front and rear loads Mz of the tower bottom btm and lateral load My btm , the formula is as follows:

[0083] Mz top =Sttx·sind([Az_nac]-a)+Stty·cosd([Az_nac]-a)

[0084] My top =Sttx·cosd([Az_nac]-a)-Stty·sind([Az_nac]-a)

[0085] Mz btm =Stx·sind([Az_nac]-b)+Sty·cosd([Az_nac]-b)

[0086] My btm =Stx·cosd([Az_nac]-b)-Sty·sind([Az_nac]-b)

[0087] Wherein, Sttx is the load in the X-axis direction measured by the strain gauge at the top of the tower; Stty is the load in the Y-axis direction measured by the strain gauge at the top of the tower; Stx is the load in the X-axis direction measured by the strain gauge at the bottom of the tower; Sty is the load in the Y-axis direction measured by the strain gauge at the bottom of the tower; Az_nac is the nacelle azimuth output by the main control of the wind turbine; a is the nacelle azimuth corresponding to the trough of Sty; b is the nacelle azimuth corresponding to the trough of Sty.

[0088] Example 3

[0089] This embodiment discloses a storage medium storing a program. When the program is executed by a processor, the wind turbine yaw control method based on tower load described in Embodiment 1 is implemented.

[0090] The storage medium in this embodiment can be a disk, an optical disk, a computer memory, a read-only memory (ROM), a random access memory (RAM), a USB flash drive, a mobile hard disk, or other media.

[0091] Example 4

[0092] This embodiment discloses a computing device, including a processor and a memory for storing a program executable by the processor. When the processor executes the program stored in the memory, the tower load-based wind turbine yaw control method described in Embodiment 1 is implemented.

[0093] The computing device described in this embodiment may be a desktop computer, a laptop computer, a smart phone, a PDA handheld terminal, a tablet computer, a programmable logic controller (PLC), or other terminal devices with a processor function.

[0094] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. A wind turbine yaw control method based on tower load, characterized in that: The following steps are involved: 1) Measure the tower load, including the front and rear loads Mz at the top of the tower top and lateral load My top And the front and rear loads Mz of the tower bottom btm and lateral load My btm , and the measured tower load is filtered through a sliding average filter; 2) Calculate the filtered tower load using the following formula to obtain the load My representing the lateral direction of the tower: Tower and represents the load Mz in the fore-aft direction of the tower Tower : My Tower = Filter My btm -FilterMy top Mz Tower = Filter Mz btm -Filter Mz top In the formula, filter My btm Represents the load on the lateral direction of the tower bottom after filtering, and the filtered My top represents the load on the lateral direction of the tower top after filtering, so My Tower The load on the lateral direction of the tower is purely the tower, not including the main engine of the wind turbine; the filter Mz btm Represents the load in the front and rear directions of the tower bottom after filtering, and the filtered Mz top represents the load on the top of the tower in the fore-aft direction after filtering, so Mz Tower The load on the tower in the front and rear directions is purely on the tower, excluding the main engine of the wind turbine; 3) My Tower , Mz Tower The yaw angle A is calculated by taking the inverse tangent, and the formula is as follows: A=arctan(My Tower / Mz Tower ) 4) Correcting the yaw angle A by multiplying different yaw angle ranges by a correction coefficient, wherein the larger the yaw angle range, the smaller the correction coefficient; 5) The corrected yaw angle A is issued as a yaw command.

2. A wind turbine yaw control method based on tower load according to claim 1, characterized in that: In step 1), four strain gauges are installed at the bottom and top of the tower, one every 90°, to measure the front and rear loads Mz at the top of the tower. top and lateral load My top And the front and rear loads Mz of the tower bottom btm and lateral load My btm , the formula is as follows: Mz top =Sttx·sind([Az_nac]-a)+Stty·cosd([Az_nac]-a) My top =Sttx·cosd([Az_nac]-a)-Stty·sind([Az_nac]-a) Mz btm =Stx·sind([Az_nac]-b)+Sty·cosd([Az_nac]-b) My btm =Stx·cosd([Az_nac]-b)-Sty·sind([Az_nac]-b) Wherein, Sttx is the load in the X-axis direction measured by the strain gauge at the top of the tower; Stty is the load in the Y-axis direction measured by the strain gauge at the top of the tower; Stx is the load in the X-axis direction measured by the strain gauge at the bottom of the tower; Sty is the load in the Y-axis direction measured by the strain gauge at the bottom of the tower; Az_nac is the nacelle azimuth output by the main control of the wind turbine; a is the nacelle azimuth corresponding to the trough of Sty; b is the nacelle azimuth corresponding to the trough of Sty.

3. The method for controlling the yaw of a wind turbine generator system based on tower load according to claim 1, characterized in that: In step 5), when the yaw error of the wind turbine set is greater than 5°, the yaw is started; when the yaw error of the wind turbine set is less than 2°, the yaw is stopped; and more than 10 seconds after the yaw is stopped, the yaw is allowed to start again.

4. A wind turbine yaw control system based on tower load, characterized in that: include: Tower load measurement module, used to measure tower loads, including the front and rear loads Mz at the top of the tower top and lateral load My top And the front and rear loads Mz of the tower bottom btm and lateral load My btm , and the measured tower load is filtered through a sliding average filter; The first calculation module is used to calculate the filtered tower load using the following formula to obtain the load My representing the lateral direction of the tower Tower and represents the load Mz in the fore-aft direction of the tower Tower : My Tower = Filter My btm -FilterMy top Mz Tower = Filter Mz btm -Filter Mz top In the formula, filter My btm Represents the load on the lateral direction of the tower bottom after filtering, and the filtered My top represents the load on the lateral direction of the tower top after filtering, so My Tower The load on the lateral direction of the tower is purely the tower, not including the main engine of the wind turbine; the filter Mz btm Represents the load in the front and rear directions of the tower bottom after filtering, and the filtered Mz top represents the load on the top of the tower in the fore-aft direction after filtering, so Mz Tower The load on the tower in the front and rear directions is purely on the tower, excluding the main engine of the wind turbine; The second calculation module is used to calculate the My calculated by the first calculation module Tower , Mz Tower The yaw angle A is calculated by taking the inverse tangent, and the formula is as follows: A=arctan(My Tower / Mz Tower ) A yaw angle correction module, used to correct the yaw angle A calculated by the second calculation module, based on different yaw angle ranges multiplied by a correction coefficient, wherein the larger the yaw angle range, the smaller the correction coefficient; The yaw instruction issuing module is used to issue a yaw instruction based on the yaw angle A corrected by the yaw angle correction module.

5. A wind turbine yaw control system based on tower load according to claim 4, characterized in that: For the tower load measurement module, four strain gauges need to be installed at the bottom and top of the tower, one every 90°, to measure the front and rear loads Mz at the top of the tower. top and lateral load My top And the front and rear loads Mz of the tower bottom btm and lateral load My btm , the formula is as follows: Mz top =Sttx·sind([Az_nac]-a)+Stty·cosd([Az_nac]-a) My top =Sttx·cosd([Az_nac]-a)-Stty·sind([Az_nac]-a) Mz btm =Stx·sind([Az_nac]-b)+Sty·cosd([Az_nac]-b) My btm =Stx·cosd([Az_nac]-b)-Sty·sind([Az_nac]-b) Wherein, Sttx is the load in the X-axis direction measured by the strain gauge at the top of the tower; Stty is the load in the Y-axis direction measured by the strain gauge at the top of the tower; Stx is the load in the X-axis direction measured by the strain gauge at the bottom of the tower; Sty is the load in the Y-axis direction measured by the strain gauge at the bottom of the tower; Az_nac is the nacelle azimuth output by the main control of the wind turbine; a is the nacelle azimuth corresponding to the trough of Sty; b is the nacelle azimuth corresponding to the trough of Sty.

6. A wind turbine yaw control system based on tower load according to claim 4, characterized in that: For the yaw command issuing module, when the yaw error of the wind turbine is greater than 5°, the yaw is started; when the yaw error of the wind turbine is less than 2°, the yaw is stopped; and yaw is allowed to resume after more than 10s of stopping yaw.

7. A storage medium storing a program, characterized in that: When the program is executed by a processor, the wind turbine yaw control method based on tower load according to any one of claims 1 to 3 is implemented.

8. A computing device comprising a processor and a memory for storing a program executable by the processor, characterized in that: When the processor executes the program stored in the memory, the wind turbine yaw control method based on tower load according to any one of claims 1 to 3 is implemented.

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