A device for identifying the position of a fan blade, a fan control method and a system

Abstract

The present invention provides a device for identifying the position of a fan blade, a fan control method and a system. The device includes a code disk and proximity switches; the code disk is synchronously rotationally connected to the main shaft of the fan; the code disk is annular, and a plurality of groups of positioning holes corresponding to the number of fan blades are distributed thereon; the plurality of groups of positioning holes are respectively distributed on a plurality of concentric circles at different distances from the center of the code disk; each group of positioning holes includes at least one positioning hole distributed in an arc-shaped area at the same distance from the center of the code disk; the number of proximity switches is the same as the number of fan blades, and they are arranged facing the code disk; each group of proximity switches is respectively arranged facing the corresponding concentric circle of each group of positioning holes and corresponds to each group of positioning holes respectively; when the code disk rotates and the positioning hole group on the concentric circle passes by the corresponding proximity switch, the proximity switch generates a pulse signal. The present invention can identify the blades that are about to operate in the dangerous area below the fan nacelle plane and may collide with the tower barrel.

Description

Technical Field

[0001] The present invention relates to the technical field of wind turbine control, and particularly to a device for identifying the position of a wind turbine blade, a method and a system for controlling a wind turbine. Background Art

[0002] With the development of wind power generation technology and the increasingly fierce competition in the wind power market, areas with poor wind energy quality, such as complex wind resource areas with low wind speeds and high turbulence, are gradually being developed. Especially in mountainous areas, due to terrain factors such as narrow tube terrain and gentle slopes, negative wind shear wind conditions are more likely to occur: as the height in the vertical direction increases, the wind speed shows a gradually decreasing trend.

[0003] In order to improve economic efficiency, the single-unit capacity and rotor diameter of wind turbines are continuously increasing, and the blades of wind turbines are getting longer and longer, with a significant decrease in stiffness. This makes the impact of negative wind shear on the wind turbine continuously intensify. The direct impact is that the uneven force on the blades leads to an increase in the root load of the blades, which not only significantly increases the unbalanced load on the rotor plane, but also easily causes the situation of the blade sweeping the tower, seriously endangering the safety of the whole machine.

[0004] Currently, in order to solve the problem of blade sweeping the tower, some detect the wind speed in front of the hub height and adjust the blades in advance to reduce the thrust. Some detect the vertical wind shear in a partial area in front of the hub and determine whether to change the blade position according to whether the wind speed change exceeds a threshold.

[0005] The prior art has the following defects:

[0006] 1. Adjusting the blades in advance refers to the wind speed information at the hub height, and does not involve the wind speed below the hub height, which has a greater impact, and cannot well solve the problem of tower sweeping caused by negative wind shear.

[0007] 2. Detecting the wind shear in a partial vertical area in front of the hub, due to the limited detection range, cannot completely detect the wind conditions of the entire blade height. Coupled with complex calculations and the same pitch change of the three blades, it cannot well avoid the risks brought by negative wind shear. Summary of the Invention

[0008] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a device for identifying the position of a wind turbine blade, a method and a system for controlling a wind turbine, which can identify the blades in the dangerous area that is about to operate below the plane of the wind turbine nacelle and may collide with the tower, so as to solve the problem of tower sweeping caused by ultra-long blades under negative wind shear.

[0009] To achieve the above purpose, the present invention is implemented by the following technical solutions:

[0010] In a first aspect, the present invention provides a device for identifying the position of a fan blade, comprising a code disk and proximity switches;

[0011] The code disk is synchronously rotationally connected to the main shaft of the fan; the code disk is annular, and a plurality of groups of positioning holes corresponding to the number of fan blades are distributed thereon;

[0012] The plurality of groups of positioning holes are respectively distributed on a plurality of concentric circles at different distances from the center of the code disk; each group of positioning holes includes at least one positioning hole distributed in an arc region at the same distance from the center of the code disk;

[0013] The number of the proximity switches is the same as the number of fan blades, and they are fixedly arranged facing the code disk; each group of proximity switches is respectively arranged facing the concentric circle corresponding to each group of positioning holes and corresponds to each group of positioning holes respectively;

[0014] When the code disk rotates and the group of positioning holes on the concentric circle passes by the corresponding proximity switch, the proximity switch generates a pulse signal, indicating that the blade corresponding to this group of positioning holes is in the danger area.

[0015] The effects achieved by the above settings: By using a blade identification device that rotates with the main shaft of the fan to identify the blades that are about to operate below the plane of the fan nacelle and may collide with the tower barrel, and determining the blades that are about to enter the danger area through the code disk and proximity switches installed on the transmission chain. The position of the proximity switch can be freely set because the relative positions of the positioning holes and the blades can be freely set, as long as the corresponding blade position is in the danger area when the proximity switch is close to the positioning hole.

[0016] Further, the danger area refers to the area where the blade is below a preset height plane.

[0017] The effects achieved by the above settings: The danger area represents that the blade may collide with the tower barrel. The preset height plane can be the plane of the fan nacelle or the plane at half the length of the blade below the plane of the fan nacelle, and can be set according to experience depending on the specific situation.

[0018] Further, the number of fan blades is 3; the number of positioning holes is 3 groups; the number of proximity switches is 3.

[0019] The effects achieved by the above settings: Three fan blades are a common setting, and the settings of three groups of positioning holes and proximity switches are simple and the cost is low.

[0020] Further, each group of positioning holes includes 5 positioning holes, which are distributed in an arc region at the same distance from the center of the code disk; the first hole in each group of positioning holes corresponds to the position of the root center line of a blade.

[0021] The effects achieved by the above settings are as follows: Each group contains 5 positioning holes to improve the error tolerance rate and perform redundant measurements, preventing the positioning holes from being missed due to too high a rotational speed, thus avoiding misjudgment of the device.

[0022] The angular range of the arc area where a group of positioning holes are distributed is less than 90 degrees, which not only improves the response error tolerance rate but also prevents the warning time from being overly delayed due to too large an angular distribution of the positioning holes, resulting in a collision between the blade and the tower barrel.

[0023] Furthermore, the code disk is sleeved on the main shaft and can rotate synchronously with the main shaft.

[0024] The effects achieved by the above settings are as follows: The circular ring shape is suitable for directly sleeving on the main shaft, which can effectively ensure the detection accuracy.

[0025] Furthermore, the three concentric circles corresponding to the three groups of positioning holes are equally spaced on the circular ring surface of the code disk; the three proximity switches are arranged side by side at equal intervals and are respectively oriented towards the three concentric circles.

[0026] The effects achieved by the above settings are as follows: The equal-spacing arrangement is more conducive to the setting of the proximity switches and the positioning holes.

[0027] Furthermore, the three groups of positioning holes are 120 degrees apart around the center of the code disk; the three proximity switches are horizontally placed on the fan frame.

[0028] The effects achieved by the above settings are as follows: The 120-degree difference between groups corresponds to the positions of the three blades.

[0029] In a second aspect, the present invention provides a fan control method for coping with complex wind conditions, including the following steps:

[0030] Based on the fan blade position recognition device described in the first aspect, perform blade recognition and detection to identify the blade entering the dangerous area.

[0031] Obtain and calculate the additional angle required for the blade entering the dangerous area according to the wind speed and wind direction information in the vertical direction of the fan, and add the value of the additional angle to the original angle of the blade.

[0032] When another blade enters the dangerous area, cancel the additional angle of the original blade.

[0033] Furthermore, obtaining the wind speed and wind direction information in the vertical direction of the fan includes:

[0034] Install a nacelle-mounted lidar anemometer at both the upper and lower parts of the fan nacelle. The two lidar anemometers are set with the same wind measurement reference plane, and the wind measurement reference plane is parallel to the rotation plane of the fan impeller;

[0035] Set the lidar anemometer parameters according to the hub height, blade length, and installation position of the lidar anemometer. Measure the wind speed and direction information in the vertical direction of the wind turbine within the wind measurement reference plane.

[0036] Further, according to the wind speed and direction information in the vertical direction of the wind turbine, calculate the additional angles required for the blades entering the danger zone, including:

[0037] When the blade enters the danger zone, according to the obtained wind speed and direction information in the vertical direction of the wind turbine, after screening and processing, obtain the wind speed V at the lowest height of the blade tip wl and the wind speed V at the height of the nacelle center line hub .

[0038] Calculate the wind speed V at the lowest height of the blade tip wl and the wind speed V at the height of the nacelle center line hub . The wind speed difference dV = (V wl - V hub );

[0039] Obtain the height H at the lowest tip leaL from the height H of the hub center line hub . The height difference dH = H hub - H leaL ;

[0040] Calculate the rate of change of wind speed with height ρ = dV / dH according to the wind speed difference and height difference.

[0041] Obtain the pre-set wind speed threshold V hubThr at the height of the nacelle center line, and the rate of change of wind speed with height threshold ρ thr ;

[0042] When the wind speed V hub at the height of the nacelle center line exceeds the wind speed threshold V hubThr at the height of the nacelle center line and the value of the rate of change of wind speed with height ρ exceeds the rate of change of wind speed with height threshold ρ thr , calculate the additional angle values of each blade according to the load simulation.

[0043] The effect of the above settings: Add this additional angle to the original angle value. The controller adjusts the blade to the corresponding angle, and the control system controls the three blades to deploy different angles according to the positions of the three blades to reduce the problem of blade tower sweeping caused by uneven thrust due to reverse wind shear.

[0044] Further, the method further includes:

[0045] Real-time detect the measured rotation speed of the wind turbine blade;

[0046] Compare the measured rotational speed with the set rated rotational speed. If the rotational speed difference exceeds the threshold, control to re-adjust the original angle of the fan blades.

[0047] In a third aspect, the present invention provides a fan control system for coping with complex wind conditions, including:

[0048] A main controller for executing the fan control method as described in the second aspect;

[0049] The fan blade position recognition device as described in the first aspect, which is used for blade recognition detection to identify the blades entering the dangerous area;

[0050] Two nacelle-mounted lidar anemometers are respectively installed on the upper and lower parts of the fan nacelle.

[0051] The effects achieved by the above settings: The nacelle-mounted lidar anemometers on the upper and lower parts of the fan nacelle can prevent the occurrence of measurement blind spots and improve the measurement accuracy.

[0052] Compared with the prior art, the beneficial effects achieved by the present invention:

[0053] 1. The position of the blade of the present invention is calibrated by a code disk, and the code disk detects the blade entering the dangerous area, reducing the calculation difficulty.

[0054] 2. The present invention completely detects the wind condition information in the vertical direction through the upper and lower lidar anemometers and can completely detect the wind speed in the vertical direction;

[0055] 3. The present invention adopts an independent control mode for three blades to avoid the risk of tower sweeping. Description of the Drawings

[0056] Figure 1 It is a schematic installation diagram of a lidar anemometer;

[0057] In the figure: 11, lidar anemometer; 12, nacelle; 13, anemometry reference plane; 14, lowest tip height; 15, hub center line.

[0058] Figure 2 It is a schematic structural diagram of a fan blade position recognition device;

[0059] In the figure: 1, annular code disk; 2, positioning hole; 3, proximity switch; 4, blade root center line; 5, fan main shaft.

[0060] Figure 3 It is a control logic block diagram. Detailed Embodiments

[0061] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present invention and cannot be used to limit the protection scope of the present invention.

[0062] Embodiment 1: As Figure 2 shown, this embodiment provides a device for identifying the position of a fan blade, including a code disk and a proximity switch 3;

[0063] The code disk is synchronously rotationally connected to the main shaft 5 of the fan; the code disk is annular, and a plurality of groups of positioning holes 2 corresponding to the number of fan blades are distributed thereon;

[0064] The plurality of groups of positioning holes 2 are respectively distributed on a plurality of concentric circles at different distances from the center of the code disk; each group of positioning holes 2 includes at least one positioning hole 2 distributed in an arc region at the same distance from the center of the code disk;

[0065] The number of the proximity switches 3 is the same as the number of fan blades, and they are arranged facing the code disk; each group of proximity switches 3 is respectively arranged on the concentric circle corresponding to each group of positioning holes 2 and corresponds to each group of positioning holes 2 respectively;

[0066] When the code disk rotates and the group of positioning holes 2 on the concentric circle passes through the corresponding proximity switch 3, the proximity switch 3 generates a pulse signal, indicating that the blade corresponding to this group of positioning holes 2 is in the dangerous area.

[0067] It is determined by the code disk and the proximity switch 3 installed on the transmission chain to identify the blade that is about to enter the dangerous area. The position of the proximity switch 3 can be freely set because the relative positions of the positioning holes 2 and the blades can be freely set, as long as the corresponding blade position is in the dangerous area when the proximity switch 3 is close to the positioning holes 2.

[0068] The dangerous area means that the blade is below the preset height plane. The dangerous area represents that the blade may collide with the tower barrel. The preset height plane can be the plane of the fan nacelle 12, or the plane of half the blade length below the fan nacelle 12 plane, which can be set according to specific circumstances, but at least it needs to include the range within 60 degrees at the bottom of the blade.

[0069] Specifically, the number of the fan blades is 3; the number of the positioning holes 2 is 3 groups; the number of the proximity switches 3 is 3. Three fan blades are a common setting, and the setting of 3 groups of positioning holes 2 and proximity switches 3 is simple and the cost is low.

[0070] Preferably, each group of positioning holes 2 includes 5 positioning holes 2, which are distributed in an arc region at the same distance from the center of the code disk; the first hole in each group of positioning holes 2 corresponds to the position of the root center line of a blade. Each group containing 5 positioning holes 2 is to improve the error tolerance, perform redundant measurement, prevent missing the positioning holes 2 due to too fast rotation speed, and thus cause misjudgment of the device.

[0071] Generally speaking, for the general setting, the angular range of the arc area where a group of positioning holes are distributed should be less than 90 degrees, preferably 60 degrees, which can not only improve the response error tolerance but also prevent the warning time from being overly delayed due to an overly large angular distribution of the positioning holes.

[0072] The code disc is sleeved on the main shaft and can rotate synchronously with the main shaft. The circular ring shape is suitable for directly sleeving on the main shaft, which can effectively ensure the detection accuracy.

[0073] Three concentric circles corresponding to the 3 groups of positioning holes 2 are equally spaced on the circular ring surface of the code disc; three proximity switches 3 are arranged side by side at equal intervals and are respectively arranged facing the three concentric circles. The equal-spacing arrangement is more conducive to the setting of the proximity switches 3 and the positioning holes 2.

[0074] The 3 groups of positioning holes 2 are 120 degrees apart around the center of the code disc; the three proximity switches 3 are horizontally placed on the fan frame. The 120-degree difference between groups corresponds to the positions of 3 blades. The positions of the positioning holes 2 and the proximity switches 3 can be freely set because the relative positions of the positioning holes 2 and the blades can be freely set.

[0075] In another optional form, the three proximity switches 3 can be arranged with a 120-degree difference around the center of the code disc, and the 3 groups of positioning holes 2 are arranged side by side, so that each group of positioning holes 2 and the corresponding proximity switch 3 are aligned with a concentric circle, thus corresponding to the position relationship of one blade.

[0076] During specific use, an annular code disc 11 that rotates with the main shaft is installed on the nut of the fan main shaft 5.

[0077] Three concentric rings with different radii are equally spaced on the annular code disc 1. Each ring is distributed with a group of positioning holes 2, and each group consists of five adjacent holes. The first hole of each group of positioning holes 2 corresponds to the center line position of the root of one blade. That is, each group of positioning holes 2 corresponds to one blade.

[0078] On the plane of the fan frame, three proximity switches 3 are installed. The proximity switches 3 are arranged in a row, and the radial positions correspond to the positioning holes 2 of the three groups of code discs, that is, the three proximity switches 3 correspond to the three groups of positioning holes 2. When the main shaft rotates, it drives the code disc to rotate. When the positioning holes 2 pass by the proximity switches 3, the corresponding proximity switches 3 generate pulse signals. The blade about to enter the dangerous area is identified according to the signals of different proximity switches 3.

[0079] Embodiment 2: This embodiment provides a fan control method for coping with complex wind conditions, as Figure 3 shown, including the following steps:

[0080] Step 1: Based on the fan blade position recognition device described in Embodiment 1, perform blade recognition and detection to identify the blades entering the dangerous area.

[0081] Step 2: Obtain the wind speed and direction information in the vertical direction of the wind turbine, calculate the additional angle required for the blade entering the dangerous area, and add the value of this additional angle to the original angle of the blade.

[0082] Step 3: Cancel the additional angle of the original blade when another blade enters the dangerous area.

[0083] Specifically, a lidar anemometer 11 is installed above and below the nacelle 12 of the wind turbine to measure the wind speed and direction information on the blade rotation plane.

[0084] A blade identification device rotating with the main shaft 5 of the wind turbine is used to identify the blade that is about to operate in the dangerous area below the plane of the nacelle 12 and may collide with the tower barrel.

[0085] The control system obtains the wind direction and speed information and the blade positions, and then obtains the additional angle required for each blade according to the control strategy. The additional angle is superimposed on the corresponding blade position to reduce the thrust on the blade under severe wind conditions and reduce the risk of the wind turbine hitting the tower.

[0086] Specifically, obtaining the wind speed and direction information in the vertical direction of the wind turbine includes:

[0087] The wind speed detection system of this system is installed as Figure 1 shown. An nacelle-mounted lidar anemometer 11 is installed above and below the nacelle 12 of the wind turbine. The two lidar anemometers 11 are set with the same wind measurement reference plane 13, and the wind measurement reference plane 13 is parallel to the wind turbine impeller rotation plane. The goal of the upper and lower lidar anemometers 11 is to include the highest and lowest positions of the blade tip in the measurement range to avoid blind spots caused by the nacelle 12 and the blade blocking.

[0088] Set the parameters of the lidar anemometer 11 according to the position of the hub center line 15, the length of the blade, and the installation position of the lidar anemometer 11, and measure the wind conditions at the lowest height 14 of the blade tip and the height of the hub center line 15 of the nacelle 12 in the reference plane.

[0089] Set the parameters of the lidar anemometer 11 according to the hub height, the length of the blade, and the installation position of the lidar anemometer 11, and measure the wind speed and direction information in the vertical direction of the wind turbine in the wind measurement reference plane 13.

[0090] Specifically, calculating the additional angle required for the blade entering the dangerous area according to the wind speed and direction information in the vertical direction of the wind turbine includes:

[0091] When the blade enters the dangerous area, according to the obtained wind speed and direction information in the vertical direction of the wind turbine, after screening and processing, the wind speed V at the lowest height 14 of the wind turbine blade tip is obtained wlWind speed V at the height of the hub center line 15 of the nacelle 12 hub .

[0092] Calculate the wind speed V at the lowest height 14 of the wind turbine blade tip wl Wind speed V at the height of the hub center line 15 of the nacelle 12 hub The wind speed difference dV = (V wl - V hub ).

[0093] Obtain the height H at the lowest point of the blade tip leaL The height difference dH from the height H of the hub center line 15 hub is dH = H hub - HleaL. This height difference can be calculated based on the height H from the hub center line 15 to the lowest height HleaL of the blade tip stored in the system, or can be input by the operator hub .

[0094] Calculate the rate of change ρ of wind speed with height according to the wind speed difference and height difference. Obtain the pre-set wind speed threshold V at the height of the hub center line 15 of the nacelle 12 hubThr and the rate of change threshold ρ of wind speed with height thr .

[0095] When the wind speed V at the height of the hub center line 15 of the nacelle 12 hub exceeds the wind speed threshold V at the height of the hub center line 15 of the nacelle 12 hubThr and the value of the rate of change ρ of wind speed with height exceeds the rate of change threshold ρthr of wind speed with height, calculate the additional angle values of each blade according to the load simulation

[0096] When the wind speed V at the height of the nacelle center line hub exceeds the wind speed threshold V at the height of the hub center line 15 of the nacelle 12 hubThr and the value of the rate of change ρ of wind speed with height exceeds the rate of change threshold ρ of wind speed with height thr , it means that the lower blades in the dangerous area may collide with the tower barrel. Therefore, at this time, special adjustment of the angles of the lower blades is required

[0097] The specific additional angle values are generally calculated by load simulation software. Conventional wind turbine load simulation software can be used, or the method of calculating empirical values through simulated load tests can also be adopted. After multiple tests, record the corresponding additional angles

[0098] After calculating the additional angle values, add this additional angle to the original angle value. The controller adjusts the blade to the corresponding angle, and the control system controls the three blades to deploy different angles according to the positions of the three blades to reduce the problem of blade tower sweeping caused by uneven thrust due to reverse wind shear

[0099] The original angle is obtained according to the power mode, that is, by selecting the corresponding angle empirical value pre-stored in the power generation power mode of the wind turbine through the system, and this method is also a conventional method of the existing wind turbine blade angle control software. The determination of the original angle is determined by the software of the wind turbine blade angle control system, and this method can be applied to the conventional wind turbine blade angle control system software on the market, such as the LabVIEW wind turbine intelligent blade control system.

[0100] Such as Figure 3 , this method further includes:

[0101] Real-time detect the measured rotational speed of the wind turbine blade;

[0102] Compare the measured rotational speed with the set rated rotational speed. If the rotational speed difference exceeds the threshold, control to re-adjust the original angle of the wind turbine blade.

[0103] Embodiment 3: This embodiment provides a wind turbine control system for coping with complex wind conditions, including:

[0104] The main controller is used to execute the wind turbine control method as described in Embodiment 2;

[0105] The wind turbine blade position recognition device as described in Embodiment 1 is used to perform blade recognition detection and identify the blades entering the dangerous area;

[0106] Two nacelle 12-type lidar anemometers 11 are respectively installed on the upper part and the lower part of the wind turbine nacelle 12.

[0107] Specifically, this solution completely measures the wind condition information from the lowest tip height 14 to the highest tip height by installing two lidar anemometers 11 on the upper and lower parts of the nacelle 12, and at the same time identifies the blades entering the dangerous area, and adopts an independent control method for three blades to avoid the risk of tower sweeping.

[0108] The specific installation and use method of the wind turbine control system includes:

[0109] 1. Measure the wind speed and wind direction information in the area from the lowest tip height 14 to the hub center line 15 height of the nacelle 12 by using the lidar anemometer 11, and process the collected wind speed and wind direction with vectors with directions.

[0110] 1.1 Install two lidar anemometers 11 on the top and bottom of the nacelle 12.

[0111] 1.2 Set the lidar anemometer 11 according to the blade length and the wind turbine hub height. Based on the standard of being able to measure all the wind direction and wind speed information in the vertical height of the wind turbine blade, and after processing the information (data screening, deleting the wind condition information except for the two points required, eliminating), transmit it to the control system.

[0112] 2. Confirmation of blades in dangerous areas. The method of combining the code disk in Embodiment 1 with the proximity switch 3 is adopted to detect which blade is about to enter the dangerous area where it may collide with the tower barrel.

[0113] 2.1 Install the code disk on the spindle nut, and the code disk rotates with the spindle.

[0114] 2.2 The code disk is an annular device. Three concentric circles are equally distributed on the annular surface. A set of positioning holes 2 is distributed on each circle. Each set of positioning holes 2 consists of 5 holes. The groups are 120 degrees apart corresponding to the positions of the three blades. When the fan rotates, the first hole of each set of code disks corresponds to the position of the root center of a blade, which is used to distinguish different blades.

[0115] 2.3 Installation of the proximity switch 3: Install a set of three horizontally placed proximity switches 3 on the horizontal plane of the fan frame. The positions of the proximity switches 3 correspond to the three sets of positioning holes 2 respectively. When rotating, the three sets of positioning holes 2 pass through their respective corresponding proximity switches 3, that is, a signal is sent to identify the blade about to enter the dangerous area.

[0116] Determine the position of the blade. First, determine the blade entering the dangerous area, and then determine the positions of the other blades according to the relative positions of the blades. When another blade enters the dangerous area, the additional angle value of the previous blade is automatically cancelled, and so on in a cycle.

[0117] 3. Adopt the blade independent control method for the blades entering the dangerous area:

[0118] Based on the angles of the original three blades, combined with the measured wind condition information, simulate and calculate the additional angle of the blade in the dangerous area, as well as the additional angles of the other two blades to overcome vibration, and add this angle to the original angle. The original angle is obtained according to the power mode, that is, select the corresponding angle empirical value pre-stored in the power generation power mode selection system of the fan. This method is also a conventional method of the existing fan blade angle control software.

[0119] Figure 3 It is a block diagram of the fan control method. According to the wind condition information at the hub center height obtained by the lidar anemometer 11, and the difference between the rated speed and the actually measured speed of the fan's own encoder, the control system obtains the angle values of the three blades according to the control strategy.

[0120] As Figure 1 shown, when the blade enters the dangerous area, using the obtained wind condition information, after screening and processing, the wind speed V at the lowest height 14 of the fan blade tip is obtained wl and the wind speed V at the height of the hub center line 15 of the nacelle 12 hub .

[0121] Then calculate the wind speed V at the lowest height 14 of the wind turbine blade tip wl and the wind speed V at the height of the hub center line 15 of the nacelle 12 hub The difference dV = (V wl - V hub );

[0122] Then calculate the height H at the lowest point of the blade tip leaL The height difference dH between the height H from the hub center line 15 hub is dH = H hub - H leaL ;

[0123] Furthermore, calculate the rate of change ρ of the wind speed with height, ρ = dV / dH

[0124] Then set the wind speed threshold V hubThr at the height of the hub center line 15 of the nacelle 12 according to the simulation results, thr and the rate of change threshold ρ of the wind speed with height. The thresholds can be determined by empirical values or through specific tests

[0125] When the values of both V hub and ρ exceed the thresholds, calculate the additional angle values of each blade according to the load simulation. The load simulation calculation is a prior art

[0126] Add this additional angle to the original angle value, and the main controller adjusts the blade to the corresponding angle

[0127] The main controller controls the three blades to deploy different angles according to the positions of the three blades, so as to reduce the problem of blade tower sweeping caused by uneven thrust caused by reverse wind shear

[0128] Those skilled in the art should understand that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code

[0129] This application is described with reference to the flowcharts and / or block diagrams of methods, apparatuses (systems), and computer program products according to embodiments of the present application. It should be understood that each flow and / or block in the flowchart and / or block diagram, and the combination of flows and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, such that the instructions executed by the processor of the computer or other programmable data processing devices generate means for implementing the functions specified in one flow Figure 1 one flow or multiple flows and / or blocks Figure 1 or multiple blocks.

[0130] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, such that the instructions stored in the computer-readable memory generate a manufactured article including instruction means that implement the functions specified in one flow Figure 1 one flow or multiple flows and / or blocks Figure 1 or multiple blocks.

[0131] These computer program instructions can also be loaded onto a computer or other programmable data processing device, such that a series of operation steps are executed on the computer or other programmable device to generate a computer-implemented process, so that the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in one flow Figure 1 one flow or multiple flows and / or blocks Figure 1 or multiple blocks.

[0132] The above is only the preferred embodiment of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the technical principle of the present invention, several improvements and modifications can be made, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A fan control method for dealing with complex wind conditions, characterized in that: The following steps are involved: Perform blade identification detection based on the fan blade position identification device to identify blades that have entered the dangerous area; Obtain and calculate the additional angle required for the blades to enter the danger zone based on the wind speed and direction information in the vertical direction of the wind turbine, and add the value of the additional angle to the original angle of the blades; When another blade enters the danger zone, the additional angle of the original blade is cancelled; The fan blade position identification device comprises a code disk and a proximity switch; The code disc is connected to the fan main shaft for synchronous rotation; the code disc is in a circular shape and has a plurality of groups of positioning holes corresponding to the number of fan blades; The multiple groups of positioning holes are respectively distributed on multiple concentric circles with different distances from the center of the code disk; each group of positioning holes includes at least one positioning hole distributed in an arc area with the same distance from the center of the code disk; The number of the proximity switches is the same as the number of the fan blades, and they are fixedly arranged toward the code disk; each group of proximity switches is respectively arranged toward the concentric circles corresponding to each group of positioning holes, and respectively corresponds to each group of positioning holes; When the code disk rotates and the positioning hole group on the concentric circle passes the corresponding proximity switch, the proximity switch generates a pulse signal, indicating that the blade corresponding to the positioning hole group is in the danger zone; Based on the wind speed and direction information in the vertical direction of the wind turbine, calculate the additional angle required for the blades to enter the danger zone, including: When the blade enters the danger zone, the wind speed V at the lowest height of the fan blade tip is obtained after screening and processing based on the wind speed and direction information in the vertical direction of the fan. wl Wind speed V at the centerline height of the nacelle hub ; Calculate the wind speed V at the lowest height of the fan blade tip wl Wind speed V at the centerline height of the nacelle hub The wind speed difference dV = (V wl -V hub ); Get the lowest tip height H leaL Height from hub centerline H hub The height difference dH = H hub -H leaL , Calculate the rate of change of wind speed with height ρ=dV / dH based on the wind speed difference and height difference; Get the wind speed threshold V at the centerline height of the cabin hubThr and the wind speed change rate threshold ρ thr ; When the wind speed V at the centerline height of the nacelle hub Exceeding the wind speed threshold V at the centerline height of the cabin hubThr And the value of the rate of change of wind speed with height ρ exceeds the threshold value of the rate of change of wind speed with height ρ thr When the load is emulated, the additional angle value of each blade is calculated based on the load simulation.

2. The wind turbine control method for dealing with complex wind conditions according to claim 1, characterized in that: Obtain wind speed and direction information in the vertical direction of the wind turbine, including: A nacelle-type laser radar anemometer is installed at the upper part and the lower part of the wind turbine nacelle respectively, and the two laser radar anemometers are provided with the same wind measurement reference surface, and the wind measurement reference surface is parallel to the rotation plane of the wind turbine impeller; The laser radar anemometer parameters are set according to the hub height, blade length and installation position of the laser radar anemometer, and the wind speed and direction information in the vertical direction of the wind turbine is measured within the wind measurement reference plane.

3. The wind turbine control method for dealing with complex wind conditions according to claim 1, characterized in that: The method further comprises: Real-time detection of the actual speed of the fan blades; The measured rotation speed is compared with the set rated rotation speed. If the rotation speed difference exceeds a threshold value, the original angle of the fan blades is readjusted.

4. The wind turbine control method for dealing with complex wind conditions according to claim 1, characterized in that: The number of the fan blades is 3; the number of the positioning holes is 3 groups; and the number of the proximity switches is 3.

5. The wind turbine control method for dealing with complex wind conditions according to claim 4, characterized in that: Each group of positioning holes includes 5 positioning holes, which are distributed in an arc area with the same distance from the center of the code disk; the first hole of each group of positioning holes corresponds to the root center line position of a blade.

6. The wind turbine control method for dealing with complex wind conditions according to claim 4, characterized in that: The three concentric circles corresponding to the three groups of positioning holes are evenly spaced and distributed on the annular surface of the code disk; the three proximity switches are evenly spaced and arranged in parallel, and are respectively set toward the three concentric circles.

7. The wind turbine control method for dealing with complex wind conditions according to claim 6, characterized in that: The center points of the three groups of positioning holes differ by 120 degrees from the center point of the code disk; the three proximity switches are horizontally placed side by side on the fan frame.

8. A fan control system for dealing with complex wind conditions, comprising: A main controller, configured to execute the fan control method according to claim 1; The fan blade position recognition device is used to perform blade recognition detection and identify blades that have entered the dangerous area; Two nacelle-type lidar anemometers are installed on the upper and lower parts of the wind turbine nacelle respectively.

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