A device for measuring the wind direction and wind speed of the incoming flow of an upwind horizontal axis wind turbine

Abstract

The application discloses a device for measuring the wind direction and wind speed of an upwind horizontal shaft wind turbine, which is characterized by installing a set of front wind measuring components in front of a guide cone to realize the wind measurement in the upwind direction of the impeller of the wind turbine. Since the wind measurement device is not affected by the wake of the impeller, the wind measurement device has higher reliability compared with the existing wind measurement mode of setting a wind speed meter on the top of the nacelle in the impeller change, and can more accurately and reliably measure the wind direction and wind speed of the incoming flow, thereby providing reference data for the performance improvement, control and performance evaluation of the wind turbine.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of wind power, and relates to a wind measuring device, in particular to a device for measuring the wind direction and wind speed of an upwind horizontal axis wind turbine, which can accurately measure the accurate incoming flow direction and size near the hub center of the wind turbine, has high reliability and strong robustness, and has wide application prospects and market value in the field of wind power generation. BACKGROUND

[0002] In the field of wind power generation, the capture and conversion efficiency of wind energy is affected by many factors, among which accurate measurement of the wind turbine incoming flow direction and wind speed is of great significance for wind turbine control. When the wind turbine is running directly against the incoming flow, the energy absorption efficiency of wind energy is best, and the load on the unit is also correspondingly lower, so accurate measurement of wind direction and wind speed is crucial for precise control of the wind turbine. By monitoring the wind speed and direction of the incoming flow in real time, the blades of the wind turbine can be better controlled and adjusted to the best working state, thereby improving the power generation efficiency and system reliability. When measuring the wind direction, the wind vane is currently used to measure the wind direction in the industry, but for upwind units, the wind vane can only be installed in the wake area, which is greatly disturbed by the wake, so the measurement deviation is also great, and accordingly the wind alignment of the wind turbine often has a large deviation, so other wind measuring equipment (such as laser radar) needs to be used to make up for the shortcomings of the wind vane and anemometer to improve the accuracy and reliability of wind direction measurement. The accuracy of measuring wind speed and direction will also be affected by other factors, such as wind resistance when the wind turbine rotates, air pressure changes and environmental interference, etc. Therefore, it is very important to choose the right wind measuring equipment and install it in the right place, and calibration and verification are needed to ensure the accuracy and reliability of the measurement results. If the wind direction can be accurately measured, then the wind turbines in a single wind turbine or even the entire wind farm can be precisely controlled, and through the use of advanced control strategies and algorithms such as model predictive control, maximum power tracking, etc., the power generation performance of a single unit or the entire wind farm can be maximized.

[0003] Currently, the main wind direction measurement methods in the wind power industry include wind vanes, ultrasonic anemometers, and laser radars. In the prior art, such as Chinese invention patents CN101389967B and CN101929426B and related patents, pressure sensors and angle sensors are installed on the nacelle or the fairing of a wind turbine generator, and the wind speed and direction of the incoming flow of the wind turbine are determined accordingly. However, the relationship between the incoming flow speed and the surface pressure is too complex to be established, and the effects of the rotor rotation, the inclination deformation of the tower and the tower under load are also difficult to correct, and there is also a lack of universality. Specifically, first, the relationship between the incoming flow speed and the surface pressure is very complex, which means that it is relatively difficult to determine the wind direction and speed using the above method. Although the pressure sensor and the angle sensor can provide information about the pressure and angle of the wind turbine blade surface, it is necessary to perform complex calculations and simulations to convert this information into information about the incoming flow speed and direction. This will increase uncertainty and errors, thereby affecting the accuracy of the results. Second, factors such as the rotation of the wind turbine rotor, the inclination deformation of the tower and the tower under load will also affect the measurement of wind speed and direction. These factors will change the pressure and angle of the blade surface, resulting in inaccurate measurement results. Although dynamic correction of the rotor and the tower can be used to correct these effects, it requires complex control algorithms and high-precision sensors to achieve, which is costly and difficult. Finally, this method also has problems in terms of universality for different types of wind turbines. Due to the differences in the shape, size and material of the fairing and blades of different types of wind turbines, the use of the same sensors and algorithms to measure wind speed and direction may have different effects. Therefore, the above method may need to be customized and adjusted for different wind turbines, which is costly and difficult.

[0004] The common prior art including the above patent has its respective defects and disadvantages, for example: (1) for the wind vane, the cup anemometer, the ultrasonic anemometer and the like, the accuracy thereof is low, especially for the upwind wind turbine, since the wind measuring device is usually installed above the nacelle and works in the wake range of the impeller, directly affected by the wake, the wind vane and the anemometer are in the separated airflow with great fluctuation, resulting in great uncertainty of the measurement result and failing to truly reflect the wind direction; (2) for the wind measuring means by installing the pressure sensor and the angle sensor on the nacelle or the fairing of the wind turbine, the calibration is complicated and lacks practicability due to the influence of the shape of the fairing, the nacelle and the inner side of the blade; (3) for the laser radar, although the wind speed and the wind direction can be measured accurately, the cost is high and the calibration is complicated, and the laser source has a problem of service life and is affected by the weather environment (such as fog, rainfall and snowfall), for example, too clean air or too much suspended matter will affect the reliability and accuracy of the wind speed measurement. In summary, in the wind power industry, accurate measurement of the wind direction and the wind speed has always been a difficult problem, and various existing measurement methods have certain defects and disadvantages. In order to solve these problems, it is necessary to deeply research, develop and improve the wind measuring technology to improve the operation efficiency of the wind turbine and the energy utilization rate. SUMMARY

[0005] (I) Invention purpose

[0006] In view of the above defects and disadvantages of the prior art, the present application aims to provide a device for measuring the wind direction and the wind speed of the upwind horizontal axis wind turbine, which is mainly characterized by installing a front wind measuring component in front of the fairing of the upwind horizontal axis wind turbine to measure the wind direction and the wind speed, using gravity to make the front wind measuring component approximately stay in front of the fairing, and the front wind measuring component can automatically adjust and calibrate according to the running state of the wind turbine to ensure the accuracy and stability of the measurement result. The device for measuring the wind direction and the wind speed of the upwind horizontal axis wind turbine of the present application has higher reliability and stronger robustness than the prior art, and can more accurately and reliably measure the wind direction and the wind speed, which uses gravity to make the front wind measuring component approximately stay in front of the fairing, avoiding the problems of wake interference and signal noise in the traditional wind vane measurement, improving the measurement accuracy and stability. At the same time, the front measuring device has a simple structure and is easy to install and maintain. The present application is suitable for measuring the upwind horizontal axis wind turbine and has a wide application prospect in the field of wind power generation. By accurately measuring the wind direction and the wind speed, precise control of a single wind turbine or even the wind turbines in the entire wind farm can be realized, and the power generation performance of the single turbine or the entire wind farm is maximized.

[0007] (II) Technical solution

[0008] The technical scheme adopted by the present application to achieve the object and solve the technical problems is as follows:

[0009] A device for measuring the wind speed and direction of the upwind horizontal axis wind turbine, comprising at least a guide cone arranged on the hub of the wind turbine and a front wind measuring component arranged on the guide cone, and a three-dimensional Cartesian coordinate system is defined according to the wind turbine, wherein the horizontal direction opposite to the wind turbine is the y-axis, the direction perpendicular to the y-axis and in the horizontal plane is the x-axis, and the vertical upward direction is the z-axis, characterized in that,

[0010] The front wind measuring component is arranged at the front end of the guide cone, and comprises at least a horizontal rigid rod, a movable rigid rod, a weight, an anemometer and a wind vane, wherein,

[0011] The horizontal rigid rod and the movable rigid rod are both elongated rod-shaped components, wherein the horizontal rigid rod extends along the y-axis direction and is consistent with the center line of the guide cone, one end of the horizontal rigid rod is rigidly connected with the front end of the guide cone and rotates synchronously with the guide cone, and the other end of the horizontal rigid rod is movably connected with the upper end of the movable rigid rod through a hinge, the hinge is a certain direction constraint hinge, so that the end of the movable rigid rod can freely swing around the x-axis and the y-axis without constraint and has no rotational freedom in the z-axis direction relative to the horizontal rigid rod; the lower end of the movable rigid rod is rigidly connected with the weight, and the torsional stiffness of the movable rigid rod as a whole should be such that the torsional torque generated by the movable rigid rod itself and the related components arranged thereon under a large wind force level does not cause torsional deformation of the movable rigid rod itself and affect the wind measurement accuracy.

[0012] The weight of the weight should be one order of magnitude higher than the weight of the movable rigid rod, and the weight is always in a vertically downward state under its own gravity during the rotation of the guide cone;

[0013] The anemometer and the wind vane are fixedly arranged on the movable rigid rod, the weight and / or the extension thereof through their rigid supports without interference between them, and the anemometer and the wind vane are communicatively connected with the wind turbine control system to transmit the measurement data to the wind turbine control system.

[0014] In a preferred example of the present application, the anemometer and the wind vane are fixedly arranged on the movable rigid rod near the lower end and above the weight through their rigid supports, and the anemometer and the wind vane are respectively fixed on the movable rigid rod or the weight. When arranging the anemometer and the wind vane, the anisotropy of the incoming flow should be considered to ensure accurate measurement results in different directions. In addition, in order to reduce the interference of the wind field, a multi-point averaging method or a differential method can be used to improve the measurement method.

[0015] In the preferred embodiment of the present application, the anemometer and the wind vane are in communication connection with the wind turbine control system through wired or wireless mode to realize the transmission of the measured data to the wind turbine control system.

[0016] In the preferred embodiment of the present application, the anemometer and the wind vane are above the horizontal rigid rod in the height direction and are fixedly arranged at the upper end of the movable rigid rod through the rigid support thereof.

[0017] In the preferred embodiment of the present application, a plurality of anemometers and wind vanes are arranged on the movable rigid rod and are arranged at different positions respectively to obtain more accurate and comprehensive inflow information.

[0018] In the alternative embodiment of the present application, the anemometer and the wind vane are each provided with a self-weight, and in the case where the weight is cancelled, the anemometer and the wind vane are fixedly arranged near the lower end of the movable rigid rod through the rigid support thereof.

[0019] In the preferred embodiment of the present application, the weight is an adjustable weight, so that the adjustment can be made according to the actual situation to obtain the best measurement effect under different working conditions.

[0020] In the preferred embodiment of the present application, the weight is a solid sphere, the aerodynamic drag coefficient of which is about 0.5, and the deflection angle of the solid sphere around the x-axis under the action of the aerodynamic force F is calculated, the wind direction measured by the wind vane is corrected, and the aerodynamic force F aero and the weight G of the solid sphere are calculated, and the deflection angle of the solid sphere around the x-axis under the action of the aerodynamic force is calculated. According to the following relationship, the deflection angle of the solid sphere around the x-axis under the action of the aerodynamic force is calculated:

[0021]

[0022] The length of the movable rigid rod is L, the movable rigid rod and the solid sphere form a pendulum system, and the swing period T of the pendulum system is:

[0023]

[0024] In the above formulae, F aeRO is the aerodynamic force received by the solid sphere, is the deflection angle of the solid sphere around the x-axis under the action of the aerodynamic force, G is the weight of the solid sphere, p 空气 is the density of the incoming air, V is the wind speed of the incoming air, R is the radius of the solid sphere, Cd is the aerodynamic drag coefficient of the solid sphere, p 固 is the density of the solid sphere, G is the acceleration of gravity, and T is the swing period of the pendulum system.

[0025] In further examples of the present application, the hinge is provided with a structure that provides damping in at least two rotation directions around the y-axis and the x-axis, so as to reduce the possibility of the solid sphere oscillating around the y-axis and the x-axis, and / or to use the air resistance of the shape of the weight during oscillation as a damping force to attenuate the amplitude, with the drag coefficient of a sphere being about 0.5 and the drag coefficient of a cube being about 1.05.

[0026] In further examples of the present application, a plurality of pressure sensors are arranged on the surface of the solid sphere, each of the pressure sensors being arranged on the surface of the solid sphere in the manner of a five-hole probe, so as to obtain a more accurate flow direction and size by measuring the pressure values of several points on the surface of the solid sphere using the five-hole probe principle.

[0027] In preferred examples of the present application, the movable rigid rod has an upward deflection angle at the connection of the upper end, so that the movable rigid rod deforms the end point after being loaded, and the hinge is located above the center line of the fairing. Due to the bending deformation of the horizontal rigid rod after being loaded, the backward inclination of the unit after being loaded, the inclination angle of the impeller itself, and / or the installation deviation of the horizontal rigid rod, during the rotation of the impeller, the weight, the anemograph, and the wind vane will move around the rotation axis of the impeller, which in turn will affect the wind speed measurement. Therefore, the movable rigid rod can be upwardly deflected by a certain angle, so that the movable rigid rod deforms the end point after being loaded, i.e. the hinge is located on the rotation axis of the impeller.

[0028] In preferred examples of the present application, if the clearance between the weight and the fan is sufficient, the length of the horizontal rod can be shortened to zero, i.e. the hinge is directly connected to the fairing.

[0029] The device for measuring the incoming wind direction and wind speed of an upwind horizontal axis wind turbine of the present application can use aerodynamic simulation technology to optimize the structure of the pre-measuring wind component when designing, so as to ensure that it can work stably under various working conditions and obtain the best measurement effect.

[0030] (Three) Technical effects

[0031] Compared with the prior art, the device for measuring the incoming wind direction and wind speed of an upwind horizontal axis wind turbine of the present application has significant technical advantages, mainly in that:

[0032] (1) The device for measuring the incoming wind direction and wind speed of an upwind horizontal axis wind turbine of the present application uses gravity to keep the wind direction and wind speed measuring equipment from rotating with the impeller, and approximately keeps it stationary in front of the impeller in space. The mechanism is similar to a "tumbler", and the wind direction and wind speed are measured on the mechanism.

[0033] (2) The device for measuring the wind direction and speed of the upwind horizontal axis wind turbine according to the present application has higher credibility and can more accurately and reliably measure the wind direction and speed of the incoming flow, compared with the prior art wind measuring method of setting a wind speed meter on the top of the nacelle, because it is not affected by the tail flow of the impeller. Moreover, the present application is less affected by the rotation of the impeller and the inclination of the unit under wind load when measuring the wind, and can make relevant data correction or compensation on the hardware, and has stronger practicability. BRIEF DESCRIPTION OF DRAWINGS

[0034] Figure 1 It is a schematic diagram of the device for measuring the wind speed and direction of the upwind horizontal axis wind turbine according to the present application.

[0035] Figure 2 It is an assembly schematic diagram of the fairing and the front wind measuring component in the present application.

[0036] Figure 3 It is an installation schematic diagram of several front wind measuring components in the present application.

[0037] Figure 4 It is a force diagram of the front wind measuring component under wind load in the present application.

[0038] Figure 5 It is a displacement deformation and compensation schematic diagram of the front wind measuring component in the present application.

[0039] BRIEF DESCRIPTION OF DRAWINGS:

[0040] 10 - fairing, 20 - front wind measuring component, 21 - horizontal rigid rod, 22 - hinge, 23 - movable rigid rod, 24 - wind speed meter, 25 - wind vane, 26 - weight. DETAILED DESCRIPTION

[0041] In order to better understand the present application, the content of the present application will be further illustrated below in combination with embodiments, so that the advantages and features of the present application can be more easily understood by those skilled in the art. It should be noted that the following description is only a preferred embodiment of the present application, but the content of the present application is not limited to the following embodiments. In fact, various modifications and changes can be made in the present application without departing from the scope or spirit of the present application, which will be apparent to those skilled in the art. For example, features shown or described as part of one embodiment can be used with another embodiment to produce yet another embodiment. Therefore, it is intended that the present application include such modifications and changes within the scope of the appended claims and their equivalents.

[0042] Currently, the inflow measurement and control of horizontal axis wind turbine is an important research direction in the field of wind power generation. For the horizontal axis wind turbine, the anemometer and wind vane are usually installed on the nacelle cover behind the impeller in the prior art. Due to the rotating motion of the horizontal axis wind turbine and the aerodynamic characteristics of the blade, especially the disturbance, turbulence and non-uniformity of the impeller wake, the anemometer and wind vane work in a very unstable flow, which will affect the measurement accuracy of the anemometer and wind vane, and thus the anemometer and wind vane cannot reflect the real inflow wind speed and direction. Although the power control of the wind turbine does not rely on the anemometer, the wind turbine mainly relies on the wind vane when it is upwind. Since the wind vane works in the impeller wake, the wind turbine often has a large deviation when it is upwind. The deviation of the wind turbine will directly affect the output power and power generation efficiency of the unit. When the wind turbine works in a non-ideal upwind deviation, the change of torque and speed will cause the load of the power system to change, thereby causing the output power of the generator to change. On the one hand, the wind turbine loses part of the power generation capacity; on the other hand, due to the measurement error of the wind vane and the deviation of the wind turbine, the wind turbine needs to be adjusted frequently, which will cause the unit to work under high cyclic load and may cause some mechanical stress and fatigue, affecting the reliability and service life of the unit. Therefore, the deviation is an important technical problem, which needs to be considered and optimized in the design, operation control and other aspects of the unit.

[0043] For the horizontal axis wind turbine, the wind measurement is usually affected by the impeller wake, especially the root of the blade corresponding to the measurement point. There is usually a strong flow separation phenomenon. Due to the disturbance of the blade wake, the anemometer and wind vane work in the separated flow, and it is difficult to obtain stable and reliable wind direction and speed measurement values. Therefore, only the wind measurement in front of the impeller can provide meaningful wind speed and direction measurement data. This is because the air flow in front of the impeller is relatively stable and is not affected by the impeller wake, so that the wind measurement device can work in a relatively stable flow environment, thereby obtaining more accurate and reliable wind direction and speed data. Therefore, in the design and operation of the upwind wind turbine, the measurement point in front of the impeller should be arranged to obtain more accurate and reliable wind speed and direction data, and improve the operation efficiency and power generation capacity of the unit.

[0044] In order to solve the series of defects and deficiencies of low measurement accuracy caused by installing the anemometer and wind vane on the nacelle cover behind the impeller in the prior art, and to improve the accuracy and accuracy of wind speed and direction measurement, the device for measuring the inflow wind speed and direction of the upwind horizontal axis wind turbine provided by the present application is shown as Figures 1-5 The technical scheme is implemented as follows:

[0045] The device for measuring the wind speed and direction of the upwind horizontal axis wind turbine comprises a guide vane 10 arranged on the hub of the wind turbine and a front wind measuring component 20 arranged on the guide vane 10, and a three-dimensional Cartesian coordinate system is defined according to the wind turbine, wherein the direction opposite to the wind turbine is the y-axis, the direction perpendicular to the y-axis and in the horizontal plane is the x-axis, and the vertical upward direction is the z-axis.

[0046] As shown in Figure 1 , 2 , the front wind measuring component 20 is arranged on the front end of the guide vane 10, and the front wind measuring component 20 comprises at least a horizontal rigid rod 21, a movable rigid rod 23, a weight 26, an anemograph 24 and a wind vane 25. The horizontal rigid rod 21 is a horizontal rod with sufficient rigidity, and the horizontal rigid rod 21 extends along the y-axis direction and is consistent with the center line of the guide vane 10. One end of the horizontal rigid rod 21 is fixedly connected with the front end of the guide vane 10 and rotates synchronously with the guide vane 10, and the other end of the horizontal rigid rod 21 is movably connected with the upper end of the movable rigid rod 23 through a hinge 22. The hinge 22 is a certain direction constraint hinge, which can make the movable rigid rod 23 freely swing around the x-axis and the y-axis, and has no rotational freedom in the z-axis direction. The movable rigid rod 23 has sufficient torsional rigidity, and the torsional rigidity of the movable rigid rod and the related components arranged thereon should be sufficient to prevent the torsional deformation of the movable rigid rod and the related components arranged thereon from affecting the wind measurement accuracy under a large wind force. The weight 26 is fixedly connected with the movable rigid rod 23. The weight of the weight 26 should be one order of magnitude higher than the weight of the movable rigid rod, and the weight 26 is always in the vertical downward state under the action of gravity during the rotation of the impeller. The anemograph 24 and the wind vane 25 are fixedly arranged on the movable rigid rod 23, the weight 26 and / or the extension part thereof through their rigid supports without interference between each other, and the anemograph 24 and the wind vane 25 are in communication connection with the wind turbine control system.

[0047] As shown in Figure 3 , the device for measuring the wind speed and direction is arranged on the movable rigid rod 23 or the weight 26 or the extension part thereof, such as the anemograph 24 and the wind vane 25. Alternatively, the wind vane 25 and the anemograph 24 can be directly selected as the plumb weight, and the measurement data can be transmitted to the wind turbine control system through wired or wireless mode.

[0048] In the device for measuring the wind speed and direction of the upwind horizontal axis wind turbine, the weight 26 is preferably a spherical body, and the aerodynamic drag coefficient Cd of the weight 26 is about 0.5. The angle around the x-axis can be calculated according to the measured wind speed and the weight of the weight 26, and the measured wind direction can be corrected, as shown in Figure 4 , the aerodynamic force F aeroand the gravity G of the weight ball, assuming that the weight ball is a solid body, the radius of which is R, the deflection angle around the x axis satisfies the following relationship:

[0049]

[0050] wherein F aero is the aerodynamic force received by the weight ball, is the deflection angle of the weight around the x axis under the action of the aerodynamic force, G is the gravity of the weight ball, p 空气 is the density of the incoming air, v is the wind speed of the incoming air, R is the radius of the solid weight ball, Cd is the aerodynamic drag coefficient of the solid weight ball, p 固 is the density of the solid weight ball, and g is the acceleration of gravity. According to the above relationship, for an iron ball with R = 0.1 m, the deflection angle of the weight around the x axis under the action of the aerodynamic force at a wind speed V = 10 m / s is

[0051]

[0052] The aerodynamic force F aero It is difficult to make the weight ball produce too large deflection angle and amplitude around the x axis.

[0053] Assuming that the length L of the vertical rod is 0.2 m, the swing period of the weight is

[0054]

[0055] Therefore, in the later data processing and analysis, if the influence of the weight on the single pendulum motion is considered, i.e. the period thereof needs to be considered, in addition, the sampling period of the measured data of the wind speed and the wind direction is suggested to be T / 10, so as to meet various needs of data analysis.

[0056] In the preferred example of the present application, a plurality of pressure sensors are arranged on the surface of the weight ball, each of the pressure sensors is arranged on the surface of the weight ball in the manner of a five-hole probe, the pressure values of several points on the surface of the weight ball are measured by each of the pressure sensors, and the incoming flow direction and size are obtained more accurately by using the five-hole probe principle.

[0057] For example Figure 5As shown, the device for measuring the upwind horizontal axis wind turbine incoming flow wind speed and wind direction of the application, in the actual wind measurement process, due to the bending deformation of the horizontal rigid rod 21 after being loaded, the inclination of the unit after being loaded, the inclination of the impeller itself, the installation deviation of the horizontal rigid rod 21 and many other factors, during the rotation of the impeller, the weight 26 and the wind measuring equipment (anemometer 24, wind vane 25) may rotate around the impeller rotation axis, then produce additional tangential velocity, and then affect the wind speed measurement. In order to minimize its influence, the movable rigid rod 23 can be moved upward by a certain angle through calculation, so that the movable rigid rod 23 deforms its end point, i.e. the hinge 22 on the impeller rotation axis, after being loaded. In addition, if the length of the horizontal rigid rod 21 is L, the cross-sectional stiffness is EI, and the total weight of the movable rigid rod, the anemometer, the wind vane, the weight and the like is G, then the deflection of the hinge downward is:

[0058]

[0059] Then the angle of the horizontal rigid rod 21 should be shifted upward along the direction of the fairing rotation is:

[0060]

[0061] The working principle of the device for measuring the upwind horizontal axis wind turbine incoming flow wind speed and wind direction of the application is as follows: when the wind turbine rotates, the incoming flow is directly measured by the front wind measuring component. The horizontal rigid rod is fixed to the front end of the fairing and rotates synchronously with it, and the movable rigid rod is connected with the horizontal rigid rod through the hinge. Due to the directional constraint of the hinge, the movable rigid rod can freely swing and is not limited by any rotational freedom to ensure that the movable rigid rod can rotate along the x-axis and y-axis, but will not rotate in the z-axis direction. The weight is fixed to the lower end of the movable rigid rod, so that the entire front wind measuring component can maintain a balanced state during rotation, and the mass of the weight should be one order of magnitude higher than the weight of the movable rigid rod. The anemometer and the wind vane are fixed on the movable rigid rod, the weight and the extension thereof through the rigid support, and are in communication connection with the wind turbine control system. The measurement data can be transmitted through the wind turbine control system. The application adopts the front wind measuring component, which is located at the front end of the fairing, thereby avoiding the installation error and interference caused by the traditional anemometer and wind vane arranged behind the impeller, and improving the measurement accuracy. The application adopts the hinge and the weight to maintain the balanced state, so that the movable rigid rod can freely swing and is not limited by any rotational freedom, which is beneficial to reduce the disturbance to the incoming flow and improve the measurement accuracy. The application makes the weight always in the vertical downward state, so as to reduce the disturbance to the incoming flow and improve the measurement stability. In summary, the technical scheme of the application realizes the accurate measurement of the upwind horizontal axis wind turbine incoming flow wind speed and wind direction by adopting the front wind measuring component and maintaining the balanced state through the hinge and the weight, and has the advantages of high precision, good stability and the like.

[0062] The objects of the present application are achieved completely and effectively by the above-described embodiments. Equivalent or simple changes made in accordance with the configuration, features and principles described in the patent concept of the present application are included in the scope of protection of the present application. Various modifications or supplements or similar replacements of the described specific embodiments can be made by those skilled in the art to which the present application belongs, as long as they do not deviate from the structure of the present application or exceed the scope defined by the claims, and should belong to the scope of protection of the present application.

Claims

1. A device for measuring the wind speed and direction of the incoming flow of an upwind horizontal axis wind turbine, comprising at least a nose cone arranged on the hub of the wind turbine and a front mounted anemometry unit arranged on said nose cone, defining a three dimensional Cartesian coordinate system, wherein the horizontal direction in which the wind turbine is facing is the y-axis, the direction perpendicular to the y-axis and in the horizontal plane is the x-axis and the vertical upward direction is the z-axis, characterized in that, The front wind measuring component is arranged at the front end of the fairing, and comprises at least a horizontal rigid rod, a movable rigid rod, a weight, an anemograph and a wind vane, wherein, The horizontal rigid rod and the movable rigid rod are both elongated rod-shaped components, the horizontal rigid rod extends along the y-axis direction and is consistent with the center line of the fairing, one end of the horizontal rigid rod is rigidly connected with the front end of the fairing and rotates synchronously, the other end of the horizontal rigid rod is movably connected with the upper end of the movable rigid rod through a hinge, the hinge is a certain direction constraint hinge, so that the end of the movable rigid rod can swing around the x-axis and the y-axis without constraint and has no rotational freedom in the z-axis direction; the lower end of the movable rigid rod is rigidly connected with the weight, and the torsional stiffness of the movable rigid rod as a whole should be such that the torque generated by the movable rigid rod and the related components arranged thereon under a large wind force level does not cause torsional deformation of the movable rigid rod itself and affect the wind measuring accuracy; The weight of the weight should be one order of magnitude higher than the weight of the movable rigid rod, and the weight is always in a vertically downward state under the action of its own gravity during the rotation of the fairing; the hinge is provided with structures for providing damping in the two rotation directions around the y-axis and the x-axis to reduce the swing of the weight around the y-axis and the x-axis, and the air resistance of the shape of the weight in the swing process is used as damping force to attenuate the amplitude; the anemograph and the wind vane are fixedly arranged on the movable rigid rod near the lower end in a manner that they do not interfere with each other and are located above the weight, and the anemograph and the wind vane are in communication connection with the wind turbine control system; and wherein, The weight is a solid sphere, the wind speed measured by an anemometer V and the weight of the solid sphere G the angle of deflection of the weight about the x-axis φ The wind direction measured by the wind vane is corrected by calculating the aerodynamic force F aero and the weight of the solid sphere G, the angle of deflection of the solid sphere about the x-axis under the action of the aerodynamic force φ According to The length of the active rigid rod is L and forms a pendulum system with the solid sphere, the oscillation period , the density of the incoming air flow, R , Cd , respectively the radius of the solid sphere, the aerodynamic drag coefficient, the density, g the acceleration of gravity.

2. A device for measuring the wind speed and direction of the flow incident on an upwind horizontal axis wind turbine according to claim 1, characterised in that, The anemograph and the wind vane are in communication connection with the wind turbine control system through wired or wireless mode to realize the transmission of the measurement data to the wind turbine control system.

3. A device for measuring the wind speed and direction of the flow incident on a horizontal axis wind turbine located upwind of said wind turbine according to claim 1, characterised in that, The surface of the solid sphere is arranged with a plurality of pressure sensors, each pressure sensor is arranged on the surface of the solid sphere in the manner of a five-hole probe, the pressure values of several points on the surface of the solid sphere are measured, and the five-hole probe principle is used to obtain more accurate incoming flow direction and size.

4. A device for measuring the wind speed and direction of the flow incident on a horizontal axis wind turbine located upwind of said wind turbine according to claim 1, characterised in that, The movable rigid rod has an upward offset angle at the connection of the upper end, so that the end point of the movable rigid rod is deformed after being loaded, and the hinge is located above the center line of the fairing.

5. A device for measuring the wind speed and direction of the flow incident on a horizontal axis wind turbine located upwind of the wind turbine as claimed in claim 1, characterised in that, The movable rigid rod is provided with a plurality of anemographs and wind vanes, and is arranged at different positions of the movable rigid rod to obtain more accurate and comprehensive incoming flow information.

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