Pitch angle testing method and device based on fan tilt angle instrument, fan tilt angle instrument and control system

Abstract

This invention provides a method, apparatus, wind turbine inclinometer, and control system for measuring pitch angle based on a wind turbine inclinometer, relating to the field of inertial sensor technology. The wind turbine is equipped with an absolute encoder for measuring the real-time angle of a target blade, and also with a wind turbine inclinometer for measuring the real-time angle of the target blade. The method includes: acquiring a first angle value and a second angle value; wherein the first angle value is the real-time angle value output by the wind turbine inclinometer, and the second angle value is the real-time angle value output by the absolute encoder; performing weighted fusion processing on the first and second angle values ​​to obtain the real-time pitch angle of the target blade; acquiring the real-time tip speed ratio, and determining the optimal pitch angle of the target blade based on the relationship curve between the real-time tip speed ratio and the wind energy utilization coefficient; and sending the real-time pitch angle and the optimal pitch angle to a pitch controller. The method provided by this invention can provide an accurate pitch angle.

Description

Technical Field

[0001] This invention relates to the field of inertial sensor technology, and in particular to a method, apparatus, wind turbine inclination meter, and control system for measuring pitch angle based on a wind turbine inclination meter. Background Technology

[0002] With the rapid development of wind power technology, the proportion of wind power energy in electricity resources has been increasing year by year, and the number of wind turbines has also been increasing year by year.

[0003] In related technologies, to improve the wind energy utilization rate of wind turbines, absolute encoders need to be installed on the turbine blades. The pitch angle of the turbine blades is adjusted in real time by measuring the angle measured by the absolute encoder.

[0004] However, during long-term operation, the cumulative error of the absolute encoder will continue to increase, resulting in inaccurate pitch angle obtained by the absolute encoder, which prevents the wind turbine from reaching its maximum utilization rate. Summary of the Invention

[0005] This invention provides a method, apparatus, wind turbine inclination meter, and control system for testing pitch angle based on a wind turbine inclination meter, in order to solve the problem of inaccurate wind turbine pitch angle testing in current methods.

[0006] In a first aspect, embodiments of the present invention provide a method for testing blade pitch angle based on a wind turbine inclinometer, wherein the wind turbine is equipped with an absolute encoder for measuring the real-time angle of a target blade, and the wind turbine is also equipped with a wind turbine inclinometer for measuring the real-time angle of the target blade, the method comprising:

[0007] Obtain a first angle value and a second angle value; wherein, the first angle value is the real-time angle value output by the wind turbine tilt meter, and the second angle value is the real-time angle value output by the absolute encoder;

[0008] The first angle value and the second angle value are weighted and fused to obtain the real-time pitch angle of the target blade;

[0009] The real-time tip speed ratio is obtained, and the optimal pitch angle of the target blade is determined based on the relationship curve between the real-time tip speed ratio and the wind energy utilization coefficient.

[0010] The real-time pitch angle and the optimal pitch angle are sent to the pitch controller; wherein the pitch controller is used to adjust the angle of the wind turbine blades based on the real-time pitch angle and the optimal pitch angle.

[0011] In one possible implementation, the weighted fusion process of the first angle value and the second angle value includes:

[0012] The operating scenario of the wind turbine is obtained, and the weighting coefficients corresponding to the first angle value and the second angle value are determined based on the operating scenario; wherein, the weighting coefficients corresponding to the first angle value and the second angle value are dynamically adjusted based on the operating scenario;

[0013] A weighted fusion process is performed based on the weight coefficients corresponding to the first angle value and the second angle value, the first angle value, and the second angle value.

[0014] In one possible implementation, obtaining the operating scenario of the wind turbine and determining the weighting coefficients corresponding to the first angle value and the second angle value based on the operating scenario includes:

[0015] Get real-time wind speed and real-time temperature;

[0016] Based on the real-time wind speed, the real-time temperature, and the preset extreme environment judgment criteria, an adjustment strategy for the weighting coefficients is determined; wherein, the adjustment strategy for the weighting coefficients includes an adjustment strategy based on years or an adjustment strategy based on the environment.

[0017] Based on the adjustment strategy, the weight coefficients corresponding to the first angle value and the second angle value are determined respectively.

[0018] In one possible implementation, before performing the weighted fusion process on the first angle value and the second angle value, the method further includes:

[0019] Obtain the difference between the first angle value and the second angle value;

[0020] Based on the difference between the first angle value and the second angle value, and a preset difference threshold, it is determined whether to send an error over-value warning.

[0021] In one possible implementation, determining whether to send an error over-limit warning based on the difference between the first angle value and the second angle value, and a preset difference threshold, includes:

[0022] Get real-time wind speed and real-time temperature;

[0023] Based on the real-time wind speed and the real-time temperature, determine whether the fan is in an extreme operating scenario;

[0024] If the wind turbine is not in the extreme operating scenario, and the difference between the first angle value and the second angle value is greater than the preset difference threshold, an error over-value warning will be sent.

[0025] In one possible implementation, after sending the error exceeding the warning, the following is also included:

[0026] The real-time pitch angle is determined based on the first angle value;

[0027] and / or

[0028] Send a warning notification to replace the absolute encoder.

[0029] In one possible implementation, obtaining the real-time tip speed ratio and determining the optimal pitch angle of the target blade based on the relationship curve between the real-time tip speed ratio and the wind energy utilization coefficient includes:

[0030] Obtain real-time wind speed, wind turbine radius, and real-time wind turbine rotation speed;

[0031] The real-time tip speed ratio is determined based on the real-time wind speed, rotor radius, and real-time rotor speed.

[0032] Based on the real-time tip speed ratio and wind energy utilization coefficient relationship curve, the optimal pitch angle of the target blade is determined; wherein, the wind energy utilization coefficient relationship curve is a curve determined based on the wind energy utilization coefficient, pitch angle, and tip speed ratio.

[0033] Secondly, embodiments of the present invention also provide a blade pitch angle testing device based on a wind turbine inclinometer. The wind turbine is equipped with an absolute encoder for measuring the real-time angle of a target blade, and the wind turbine is also equipped with a wind turbine inclinometer for measuring the real-time angle of the target blade. The device includes:

[0034] An acquisition module is used to acquire a first angle value and a second angle value; wherein the first angle value is the real-time angle value output by the wind turbine tilt meter, and the second angle value is the real-time angle value output by the absolute encoder;

[0035] The processing module is used to perform weighted fusion processing on the first angle value and the second angle value to obtain the real-time pitch angle of the target blade;

[0036] The determination module is used to obtain the real-time tip speed ratio and, based on the relationship curve between the real-time tip speed ratio and the wind energy utilization coefficient, determine the optimal pitch angle of the target blade.

[0037] A transmitting module is used to transmit the real-time pitch angle and the optimal pitch angle to a pitch controller; wherein the pitch controller is used to adjust the angle of the wind turbine blades based on the real-time pitch angle and the optimal pitch angle.

[0038] Thirdly, embodiments of the present invention provide a wind turbine tilt meter, including a memory and an angle controller. The memory stores a computer program, and the angle controller executes the computer program to implement the method described in the first aspect or any possible implementation of the first aspect.

[0039] Fourthly, embodiments of the present invention also provide a control system, including an absolute encoder disposed on the wind turbine blades and a wind turbine tilt meter disposed on the wind turbine blades as described in the third aspect.

[0040] The absolute encoders widely used in wind turbines are prone to accumulating significant errors after prolonged use, resulting in large deviations in the pitch angles they provide. Therefore, in this embodiment of the invention, in order to accurately test the pitch angle of the wind turbine blades, a wind turbine inclinometer is added in addition to the absolute encoder on the blade. The inclinometer measures the first angle value of the target blade in real time and simultaneously acquires the second angle value measured by the absolute encoder. After acquiring the first and second angle values, to offset the accumulation of errors or performance degradation from a single test, the first and second angle values ​​are weighted and fused to compensate for the errors of the inclinometer or absolute encoder, thus obtaining an accurate real-time pitch angle. Furthermore, to achieve maximum wind energy utilization, the wind turbine needs to reach its maximum wind energy utilization coefficient during operation, which requires the wind turbine blades to be at the optimal pitch angle. Therefore, the optimal pitch angle needs to be determined based on the relationship curve between the real-time tip speed ratio and the wind energy utilization coefficient. Once the real-time and optimal pitch angles are determined, the wind turbine tilt meter sends these two data points to the pitch controller. The pitch controller then adjusts the angle of the wind turbine blades based on the real-time and optimal pitch angles. This ensures the wind turbine blades operate at the optimal pitch angle, allowing the wind turbine to achieve maximum wind energy utilization. Attached Figure Description

[0041] Figure 1 This is a flowchart illustrating the implementation of the pitch angle testing method based on a wind turbine tilt meter provided in this embodiment of the invention.

[0042] Figure 2 This is a two-dimensional curve diagram of Cp versus λ and β provided in an embodiment of the present invention;

[0043] Figure 3 This is a three-dimensional curve diagram of Cp versus λ and β provided in an embodiment of the present invention;

[0044] Figure 4 This is a schematic diagram of the paddle pitch angle testing device based on a wind turbine tilt meter provided in an embodiment of the present invention;

[0045] Figure 5 This is a schematic diagram of the control system provided in an embodiment of the present invention. Detailed Implementation

[0046] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0047] As introduced in the background section, with the continuous increase in wind power penetration, wind turbines are being used more frequently in wind farm environments characterized by high volatility and randomness. In areas rich in wind energy, such as plateaus and coastal regions, instantaneous wind speeds can often reach 20-30 m / s, and in some extreme weather conditions, wind speeds may even reach 50 m / s. However, the optimal utilization rate of wind energy is not directly correlated with wind speed. Therefore, how to accurately adjust the blade pitch angle under different wind speeds to obtain maximum wind energy is a problem that needs to be explored in wind turbine design.

[0048] Furthermore, wind turbines currently primarily use absolute encoders to measure the blade pitch angle. However, the bearings of absolute encoders are prone to wear after prolonged use, leading to decreased rotational accuracy and uneven, unstable rotation of the encoder disk, thus causing a continuous increase in measurement errors. Therefore, how to monitor the accuracy of absolute encoders on wind turbines while reducing the cost of replacing large quantities of absolute encoders has become a pressing technical problem to be solved.

[0049] This invention addresses the problem of inaccurate pitch angle measurements caused by accumulated errors in absolute encoders over extended periods of use. It also addresses the issue of reduced wind turbine utilization due to failure to replace the encoder promptly when the accumulated error exceeds a threshold. In addition to installing an absolute encoder on the wind turbine to measure the real-time angle of the target blades, a wind turbine inclinometer is also installed on the turbine to measure the same real-time angle.

[0050] For example, a wind turbine inclinometer can be installed at the root of the target blade, and an absolute encoder can be installed at the tail of the pitch motor in the hub of the target blade. The target blade is any one of the blades in the wind turbine.

[0051] In this embodiment, the pitch angle testing method based on the wind turbine inclinometer can be integrated as a program into the angle controller within the wind turbine inclinometer to achieve pitch angle testing. The execution entity of this method is the angle controller within the wind turbine inclinometer.

[0052] See Figure 1 The document illustrates a flowchart of the implementation of the pitch angle testing method based on a wind turbine tilt meter provided in this embodiment of the invention, which is described in detail below:

[0053] S110, Obtain the first angle value and the second angle value.

[0054] The first angle value is the real-time angle value output by the wind turbine tilt meter, and the second angle value is the real-time angle value output by the absolute encoder.

[0055] Absolute encoders are the core feedback components for achieving precise control and safe operation of wind turbines. Currently, while absolute encoders on wind turbines can measure the blade pitch angle, inaccuracies can occur after prolonged use or in harsh environments due to wear and tear on the encoder components or external interference. The accuracy of the pitch angle directly affects the wind energy utilization coefficient and the overall wind energy efficiency; therefore, improving the accuracy of the pitch angle is crucial for enhancing wind energy utilization.

[0056] To improve the accuracy of blade pitch angle testing, a wind turbine tilt meter is installed on the blades in this application. The tilt meter contains an angle controller, a tilt sensor, and an angle calculation module. The angle controller acquires the first angle value output by the tilt meter and the second angle value output by the absolute encoder. The tilt sensor calculates the tilt angle by sensing changes in the gravitational component, providing real-time acceleration and angular rate information. The angle calculation module uses the acceleration and angular rate information output by the tilt sensor to deduce the angle. The angular rate information is used to account for the influence of centrifugal force. Due to the presence of centrifugal force, the angle output by the angle calculation module (which is also the angle output by the tilt meter) is affected by centrifugal force, resulting in some deviation and preventing completely accurate measurement of the blade angle.

[0057] For example, the tilt sensor here can be a tilt meter fabricated using MEMS (Micro-Electro-Mechanical Systems) technology.

[0058] S120. The first angle value and the second angle value are weighted and fused to obtain the real-time pitch angle of the target blade.

[0059] Due to the influence of centrifugal force, the first angle value measured by the wind turbine inclinometer differs from the actual angle value of the target blade. Therefore, in order to more accurately measure the real-time pitch angle of the target blade, this application requires weighted fusion processing of the first angle value measured by the wind turbine inclinometer and the second angle value measured by the absolute encoder.

[0060] In some embodiments, considering that the absolute encoder and the wind turbine tilt meter are affected by different factors in terms of test accuracy during operation, in order to eliminate the error accumulation or performance degradation of a single sensor and improve the accuracy of the obtained real-time pitch angle, it is also necessary to adjust the weighting coefficients in the weighted fusion process of the first angle value and the second angle value.

[0061] In this embodiment, the operating scenario of the wind turbine can be obtained first, and the weighting coefficients corresponding to the first angle value and the second angle value can be determined based on the operating scenario. The weighting coefficients corresponding to the first angle value and the second angle value are dynamically adjusted based on the operating scenario. Then, a weighted fusion process can be performed based on the weighting coefficients corresponding to the first angle value and the second angle value, the first angle value, and the second angle value.

[0062] Specifically, the first angle value is multiplied by its weight to obtain the first data, the second angle value is multiplied by its weight to obtain the second data, and the sum of the first data and the second data is the real-time pitch angle of the target blade.

[0063] In some embodiments, when determining the weighting coefficients corresponding to the first angle value and the second angle value, real-time wind speed and real-time temperature can be obtained first. Then, based on the real-time wind speed, real-time temperature, and a preset extreme environment judgment standard, an adjustment strategy for the weighting coefficients can be determined. Finally, based on the adjustment strategy, the weighting coefficients corresponding to the first angle value and the second angle value can be determined respectively.

[0064] Absolute encoders record blade rotation angles using mechanical gears or optical grids. The core sources of error are mechanical wear and component aging. With prolonged use, gear meshing clearances may increase, and optical components may experience signal recognition deviations due to dust / oil contamination, leading to a gradual decrease in measurement accuracy. In high-vibration environments, such as wind turbines operating continuously in strong winds, the encoder's mechanical structure will wear down more rapidly, and the error will increase even faster.

[0065] The tilt sensor inside the wind turbine tiltmeter relies on a MEMS sensor to sense gravity or angular acceleration. The core source of error is environmental interference rather than mechanical wear. In extreme scenarios, such as low / high temperatures causing sensor drift or strong vibrations interfering with gravity direction recognition, the instantaneous measurement error of the tiltmeter can suddenly increase. However, the impact of its service life on its accuracy is far less than that of an absolute encoder. For example, in low temperatures during winter, the tiltmeter may have an error of ±0.5° due to temperature compensation algorithm deviation, while an absolute encoder that has been used for one year may still maintain a stable accuracy of ±0.1°.

[0066] Therefore, considering that the error source of an absolute encoder is mainly its service life, while the error source of an inclinometer is mainly environmental interference, the adjustment strategy for the weighting coefficient can be set as an adjustment strategy based on service life or an adjustment strategy based on the environment.

[0067] In this embodiment, the adjustment strategy based on years can be:

[0068] When the service life of an absolute encoder is 0-2 years, the mechanical wear of the absolute encoder is minimal and the signal recognition is accurate. At this time, the absolute encoder is given a higher weight. For example, the weight of the second angle value tested by the absolute encoder can be set to 0.8, and the weight of the first angle value tested by the wind turbine tilt meter can be set to 0.2.

[0069] When an absolute encoder has been in use for 2-5 years, it may experience slight wear and its accuracy may begin to decline slowly. At this time, its weight can be gradually reduced. For example, the weight of the second angle value tested by the absolute encoder can be set to 0.5, and the weight of the first angle value tested by the wind turbine tilt meter can be set to 0.5.

[0070] When an absolute encoder has been in use for more than 5 years, the encoder wear will increase and the error may exceed the allowable range. At this time, it should be given a low weight. For example, the weight of the second angle value tested by the absolute encoder can be set to 0.2, and the weight of the first angle value tested by the wind turbine tilt meter can be set to 0.8.

[0071] In this embodiment, the adjustment strategy based on the environment can be:

[0072] In stable weather conditions, the weights of the first angle value measured by the wind turbine tilt meter and the second angle value measured by the absolute encoder are set based on an adjustment strategy based on the number of years.

[0073] In extreme weather conditions, such as strong winds ≥15m / s, low temperatures ≤-20℃, or high temperatures ≥40℃, strong winds can cause severe vibrations in the unit. The absolute encoder's mechanical structure may momentarily jam due to this vibration. In such cases, based on an age-based adjustment strategy, the weight of the second angle value tested by the absolute encoder should be reduced, while the weight of the first angle value tested by the wind turbine inclinometer should be increased. Similarly, extreme temperatures can cause inclinometer sensor drift. In this situation, based on an age-based adjustment strategy, the weight of the second angle value should be increased, while the weight of the first angle value should be decreased.

[0074] For example, the reduction and increase rates can be set based on environmental meteorological data from the actual application scenario, and are not limited here. For instance, the rate can be reduced or increased by 30% based on an adjustment strategy based on years, and the sum of the weights of the first angle value tested by the wind turbine tilt meter and the second angle value tested by the absolute encoder is 1.

[0075] It should be noted that the above only applies to the case where a wind turbine inclinometer and an absolute encoder are installed on any one of the blades of the wind turbine, that is, only one wind turbine inclinometer and one absolute encoder are installed in the wind turbine.

[0076] In some embodiments, considering that the cumulative error of the absolute encoder is too large, determining the real-time pitch angle based on the weighted fusion result of the first and second angle values ​​may cause significant errors and prevent the wind turbine from achieving maximum wind energy utilization. Therefore, before performing weighted fusion processing on the first and second angle values, it is necessary to determine whether to continue using the test angle of the absolute encoder.

[0077] In this embodiment, the difference between the first angle value and the second angle value can be obtained first. Then, based on the difference between the first angle value and the second angle value, and a preset difference threshold, it can be determined whether to send an error over-limit warning.

[0078] In this embodiment, when determining the relationship between the difference between the first angle value and the second angle value and the preset difference threshold, it is also necessary to consider whether the second angle value is affected by the environment. For example, whether the inaccuracy of the angle measured by the absolute encoder is due to environmental influences.

[0079] Specifically, real-time wind speed and temperature can be obtained first. Then, based on the real-time wind speed and temperature, it can be determined whether the fan is operating in an extreme scenario. Finally, if the fan is not operating in an extreme scenario, and the difference between the first angle value and the second angle value is greater than a preset difference threshold, an error over-limit warning is sent.

[0080] The specific limitations of extreme operating scenarios can be determined based on the type and operating parameters of the absolute encoder used, and will not be elaborated here.

[0081] In addition, when the cumulative error of the absolute encoder test is large, after the error exceeds the warning value, the angle controller in the wind turbine tilt meter will determine the real-time pitch angle based only on the first angle value.

[0082] In addition, to allow maintenance personnel to stay informed about the status of the absolute encoder, an early warning notification for its replacement can be sent. This allows maintenance personnel to promptly replace the absolute encoder upon receiving the notification.

[0083] S130. Obtain the real-time tip speed ratio, and determine the optimal pitch angle of the target blade based on the relationship curve between the real-time tip speed ratio and the wind energy utilization coefficient.

[0084] In some embodiments, in order to obtain the real-time tip speed ratio, it is necessary to first determine the real-time tip speed ratio based on the real-time wind speed, the rotor radius, and the real-time rotor speed.

[0085] In this embodiment, the real-time rotor speed can be obtained first. Then, the real-time wind speed can be obtained. Finally, the ratio of the product of the real-time rotor speed and the rotor radius to the real-time wind speed is determined as the real-time tip speed ratio.

[0086] In this embodiment, a gyroscope can be installed at the end of the rotating main shaft of the wind turbine, and a wind speed sensor can be installed on the nacelle of the wind turbine.

[0087] A gyroscope can be mounted on the wind turbine hub, allowing it to detect the angular velocities of the X, Y, and Z axes in real time. In actual measurements, the gyroscope outputs the AD value corresponding to the angular velocities of the three axes. Multiplying the AD value by a specific conversion factor, such as 0.06° / s, yields the angular velocity of each axis. Then, using the Pythagorean theorem, the total real-time angular velocity of the hub is calculated, thus determining the wind turbine's rotational speed. For example, if the AD value of a certain axis is 200, its angular velocity is 200 × 0.06° / s = 12° / s. The overall rotational speed of the wind turbine is then calculated by combining these values.

[0088] Once the real-time tip speed ratio is determined, the optimal pitch angle of the target blade can be determined based on the relationship curve between the real-time tip speed ratio and the wind energy utilization coefficient.

[0089] In this embodiment, the wind energy utilization coefficient relationship curve is constructed based on the wind energy utilization coefficient, blade pitch angle, and blade tip speed ratio.

[0090] Specifically, the energy absorbed by the wind turbine is:

[0091] ;

[0092] in, The wind energy absorbed by the wind turbine, measured in W. The wind energy utilization coefficient, The density of wind energy gas, in units of , This is the radius of the wind turbine rotor, in meters. This refers to the blade pitch angle of a wind turbine, measured in degrees (deg). This refers to the tip speed ratio coefficient of the wind turbine blades; The wind speed at any given time is expressed in m / s. The wind turbine absorbs energy, and the wind energy utilization coefficient is also considered. There is a positive correlation. It's about the tip speed ratio. With pitch angle The function, in practical engineering applications, The value is:

[0093] ;

[0094] ;

[0095] in, The values ​​of each coefficient are: , , , , , .

[0096] As shown in the formula above, the wind energy utilization coefficient is a coefficient related to wind speed, wind turbine speed, and blade pitch angle. Currently, wind energy utilization coefficient control strategies are limited by single-variable control. Traditional strategies only adjust generator torque (i.e., control tip speed ratio) below rated wind speed, and only adjust blade pitch angle above rated wind speed, failing to coordinate and optimize the coupling relationship between wind speed and turbine speed. Furthermore, existing controllers mostly use piecewise linearization or lookup table methods, making it difficult to dynamically track the global optimum and failing to fully utilize the surface. During the adjustment process, the lag in pitch and speed response can cause deviations from the optimal trajectory.

[0097] In this embodiment, as Figure 2 and 3 As shown, the basic characteristics of a wind turbine are mainly represented by the Cp-λ curve. Cp is an important parameter characterizing the wind turbine system, with a theoretical limit of 0.593 (Betz limit). It is closely related to the aerodynamic characteristics of the wind turbine and is constrained by the aerodynamic design and control system. It is a function of the tip speed ratio λ of the wind turbine blade and the pitch angle β. As the pitch angle β of the wind turbine blade changes, the corresponding Cp-λ curve will also change accordingly, and Cp and β have a negative correlation.

[0098] In this embodiment, by dynamically decoupling the nonlinear relationship of the Cp(λ,β) surface, Cp is maximized across the entire wind speed range, thereby determining the optimal pitch angle.

[0099] S150: Send the real-time pitch angle and the optimal pitch angle to the pitch controller.

[0100] The pitch controller is used to adjust the angle of the wind turbine blades based on the real-time pitch angle and the optimal pitch angle.

[0101] In this embodiment, after determining the optimal pitch angle and the real-time pitch angle, the angle controller inside the wind turbine tiltmeter sends the optimal pitch angle and the real-time pitch angle to the pitch controller. After receiving the optimal pitch angle and the real-time pitch angle, the pitch controller adjusts the blade pitch angle according to the difference between the optimal pitch angle and the real-time pitch angle.

[0102] In this embodiment of the invention, to accurately test the pitch angle of the wind turbine blades, in addition to installing an absolute encoder on the blades, a wind turbine inclinometer is also added. The inclinometer measures the real-time first angle value of the target blade and simultaneously acquires the second angle value measured by the absolute encoder. After acquiring the first and second angle values, to offset the accumulation of errors or performance degradation from a single test, a weighted fusion process is performed on the first and second angle values ​​to complementaryly correct the errors of the inclinometer or absolute encoder, thus obtaining an accurate real-time pitch angle. Furthermore, to ensure the wind turbine achieves maximum wind energy utilization, it is also necessary to maximize the wind energy utilization coefficient during operation, which requires the wind turbine blades to be at the optimal pitch angle. Therefore, the optimal pitch angle needs to be determined based on the relationship curve between the real-time tip speed ratio and the wind energy utilization coefficient. After determining the real-time and optimal pitch angles, the inclinometer can send these two data points to the pitch controller, which can then adjust the angle of the wind turbine blades based on the real-time and optimal pitch angles. This allows the wind turbine blades to operate at the optimal pitch angle, enabling the wind turbine to achieve maximum wind energy utilization.

[0103] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0104] The following are device embodiments of the present invention. For details not described in detail, please refer to the corresponding method embodiments described above.

[0105] Figure 4 A schematic diagram of the blade pitch angle testing device based on a wind turbine tilt meter provided in an embodiment of the present invention is shown. For ease of explanation, only the parts related to the embodiment of the present invention are shown, and are described in detail below:

[0106] A blade pitch angle testing device based on a wind turbine inclinometer, comprising: an absolute encoder on the wind turbine for measuring the real-time angle of the target blade, and a wind turbine inclinometer on the wind turbine for measuring the real-time angle of the target blade; the device includes:

[0107] The acquisition module 410 is used to acquire a first angle value and a second angle value; wherein, the first angle value is the real-time angle value output by the wind turbine inclinometer, and the second angle value is the real-time angle value output by the absolute encoder;

[0108] The processing module 420 is used to perform weighted fusion processing on the first angle value and the second angle value to obtain the real-time pitch angle of the target blade.

[0109] The determination module 430 is used to obtain the real-time tip speed ratio and determine the optimal pitch angle of the target blade based on the relationship curve between the real-time tip speed ratio and the wind energy utilization coefficient.

[0110] The transmitting module 440 is used to transmit the real-time pitch angle and the optimal pitch angle to the pitch controller; wherein, the pitch controller is used to adjust the angle of the wind turbine blades based on the real-time pitch angle and the optimal pitch angle.

[0111] In one possible implementation, the processing module 420 is used for:

[0112] The operating scenario of the wind turbine is obtained, and the weighting coefficients corresponding to the first angle value and the second angle value are determined based on the operating scenario; wherein, the weighting coefficients corresponding to the first angle value and the second angle value are dynamically adjusted based on the operating scenario.

[0113] Weighted fusion processing is performed based on the weight coefficients corresponding to the first angle value and the second angle value, the first angle value, and the second angle value.

[0114] In one possible implementation, the processing module 420 is used for:

[0115] Get real-time wind speed and real-time temperature;

[0116] Based on real-time wind speed, real-time temperature, and preset extreme environment judgment criteria, the adjustment strategy for the weighting coefficients is determined; among them, the adjustment strategy for the weighting coefficients includes an adjustment strategy based on years or an adjustment strategy based on the environment.

[0117] Based on the adjustment strategy, the weight coefficients corresponding to the first angle value and the second angle value are determined respectively.

[0118] In one possible implementation, the processing module 420 is used for:

[0119] Obtain the difference between the first angle value and the second angle value;

[0120] Based on the difference between the first angle value and the second angle value, and a preset difference threshold, it is determined whether to send an error over-value warning.

[0121] In one possible implementation, the processing module 420 is used for:

[0122] Get real-time wind speed and real-time temperature;

[0123] Based on real-time wind speed and real-time temperature, determine whether the fan is in an extreme operating scenario;

[0124] If the wind turbine is not in an extreme operating scenario, and the difference between the first angle value and the second angle value is greater than the preset difference threshold, an error over-value warning will be sent.

[0125] In one possible implementation, the processing module 420 is used for:

[0126] Based on the first angle value, determine the real-time pitch angle;

[0127] and / or

[0128] Send a warning notification to replace the absolute encoder.

[0129] In one possible implementation, module 430 is defined for:

[0130] Obtain real-time wind speed, wind turbine radius, and real-time wind turbine rotation speed;

[0131] The real-time tip speed ratio is determined based on real-time wind speed, rotor radius, and real-time rotor speed.

[0132] The optimal pitch angle of the target blade is determined based on the relationship curve between the real-time tip speed ratio and the wind energy utilization coefficient; wherein, the wind energy utilization coefficient relationship curve is a curve determined based on the wind energy utilization coefficient, the pitch angle, and the tip speed ratio.

[0133] Thirdly, the present invention also provides a wind turbine tilt meter, including a memory and an angle controller. The memory stores a computer program that can run on the angle controller. When the angle controller executes the computer program, it implements the pitch angle testing method based on the wind turbine tilt meter as described in any of the first aspects.

[0134] Fourthly, embodiments of the present invention also provide a control system, including an absolute encoder disposed on the wind turbine blades and a wind turbine tilt meter, as described in the third aspect, disposed on the wind turbine blades.

[0135] like Figure 5 As shown, a control system includes an absolute encoder 510 and a wind turbine tilt meter 520 mounted on a wind turbine. Furthermore, the control system also includes a gyroscope 530, a wind speed sensor 540, a gearbox 550, and a pitch controller 570.

[0136] The wind speed sensor 540 is installed at the rear of the system nacelle, the gyroscope 530 is installed at the end of the rotor shaft, the absolute encoder 510 is installed at the tail of the pitch motor in each blade hub, and the inclinometer 520 sensor is installed at the blade root, 0.5m from the shaft. After receiving the real-time pitch angle and optimal pitch angle from the angle controller inside the inclinometer, the pitch controller 570 adjusts the pitch angle of the wind turbine blades through the gearbox 550.

[0137] In the above embodiments, the descriptions of each embodiment have their own emphasis. Parts not detailed or described in a particular embodiment can be referred to in the relevant descriptions of other embodiments. Unless otherwise specified or in conflict with logic, the terminology and / or descriptions between different embodiments are consistent and can be referenced interchangeably. Technical features in different embodiments can be combined to form new embodiments based on their inherent logical relationships.

[0138] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included within the protection scope of the present invention.

Claims

1. A method for testing blade pitch angle based on a wind turbine tiltmeter, wherein the wind turbine is equipped with an absolute encoder for measuring the real-time angle of a target blade, characterized in that, The fan is also equipped with a fan tilt meter for measuring the real-time angle of the target blade, and the method includes: Obtain a first angle value and a second angle value; wherein, the first angle value is the real-time angle value output by the wind turbine tilt meter, and the second angle value is the real-time angle value output by the absolute encoder; The first angle value and the second angle value are weighted and fused to obtain the real-time pitch angle of the target blade; The real-time tip speed ratio is obtained, and the optimal pitch angle of the target blade is determined based on the relationship curve between the real-time tip speed ratio and the wind energy utilization coefficient. The real-time pitch angle and the optimal pitch angle are sent to the pitch controller; wherein, the pitch controller is used to adjust the angle of the wind turbine blades based on the real-time pitch angle and the optimal pitch angle; The weighted fusion process of the first angle value and the second angle value includes: Get real-time wind speed and real-time temperature; Based on the real-time wind speed, the real-time temperature, and the preset extreme environment judgment criteria, an adjustment strategy for the weighting coefficients is determined; wherein, the adjustment strategy for the weighting coefficients includes an adjustment strategy based on years or an adjustment strategy based on the environment. Based on the adjustment strategy, weight coefficients corresponding to the first angle value and the second angle value are determined respectively; wherein, the weight coefficients corresponding to the first angle value and the second angle value are dynamically adjusted based on the running scenario; A weighted fusion process is performed based on the weight coefficients corresponding to the first angle value and the second angle value, the first angle value, and the second angle value.

2. The method for testing blade pitch angle based on a wind turbine tilt meter according to claim 1, characterized in that, Before performing the weighted fusion process on the first angle value and the second angle value, the method further includes: Obtain the difference between the first angle value and the second angle value; Based on the difference between the first angle value and the second angle value, and a preset difference threshold, it is determined whether to send an error over-value warning.

3. The method for testing blade pitch angle based on a wind turbine tilt meter according to claim 2, characterized in that, The step of determining whether to send an error over-limit warning based on the difference between the first angle value and the second angle value, and a preset difference threshold, includes: Get real-time wind speed and real-time temperature; Based on the real-time wind speed and the real-time temperature, determine whether the fan is in an extreme operating scenario; If the wind turbine is not in the extreme operating scenario, and the difference between the first angle value and the second angle value is greater than the preset difference threshold, an error over-value warning will be sent.

4. The method for testing the pitch angle based on a wind turbine tilt meter according to claim 3, characterized in that, After sending the error exceeding the warning, it also includes: The real-time pitch angle is determined based on the first angle value; and / or Send a warning notification to replace the absolute encoder.

5. The method for testing blade pitch angle based on a wind turbine tilt meter according to claim 1, characterized in that, The step of obtaining the real-time tip speed ratio and determining the optimal pitch angle of the target blade based on the relationship curve between the real-time tip speed ratio and the wind energy utilization coefficient includes: Obtain real-time wind speed, wind turbine radius, and real-time wind turbine rotation speed; The real-time tip speed ratio is determined based on the real-time wind speed, rotor radius, and real-time rotor speed. Based on the real-time tip speed ratio and wind energy utilization coefficient relationship curve, the optimal pitch angle of the target blade is determined; wherein, the wind energy utilization coefficient relationship curve is a curve determined based on the wind energy utilization coefficient, pitch angle, and tip speed ratio.

6. A blade pitch angle testing device based on a wind turbine tiltmeter, wherein the wind turbine is equipped with an absolute encoder for measuring the real-time angle of a target blade, characterized in that, The fan is also equipped with a fan tilt meter for measuring the real-time angle of the target blades, the device comprising: An acquisition module is used to acquire a first angle value and a second angle value; wherein the first angle value is the real-time angle value output by the wind turbine tilt meter, and the second angle value is the real-time angle value output by the absolute encoder; The processing module is used to perform weighted fusion processing on the first angle value and the second angle value to obtain the real-time pitch angle of the target blade; The determination module is used to obtain the real-time tip speed ratio and, based on the relationship curve between the real-time tip speed ratio and the wind energy utilization coefficient, determine the optimal pitch angle of the target blade. A transmitting module is used to transmit the real-time pitch angle and the optimal pitch angle to a pitch controller; wherein, the pitch controller is used to adjust the angle of the wind turbine blades based on the real-time pitch angle and the optimal pitch angle; The processing module is also used to obtain real-time wind speed and real-time temperature; Based on the real-time wind speed, the real-time temperature, and the preset extreme environment judgment criteria, an adjustment strategy for the weighting coefficients is determined; wherein, the adjustment strategy for the weighting coefficients includes an adjustment strategy based on years or an adjustment strategy based on the environment. Based on the adjustment strategy, weight coefficients corresponding to the first angle value and the second angle value are determined respectively; wherein, the weight coefficients corresponding to the first angle value and the second angle value are dynamically adjusted based on the running scenario; A weighted fusion process is performed based on the weight coefficients corresponding to the first angle value and the second angle value, the first angle value, and the second angle value.

7. A fan tilt meter, characterized in that, The device includes a memory and an angle controller, wherein the memory stores a computer program that can run on the angle controller, and the angle controller executes the computer program to implement the pitch angle testing method based on a wind turbine tilt meter as described in any one of claims 1 to 5.

8. A control system, characterized in that, It includes an absolute encoder mounted on the wind turbine blades and a wind turbine tilt meter as described in claim 7 mounted on the wind turbine blades.

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