Wind turbine hub load monitoring method and system based on main shaft displacement

Abstract

The application discloses a kind of wind turbine hub load monitoring method and system based on main shaft displacement, comprising steps, select at least one wind turbine in same model as representative unit;Obtain main shaft displacement data and hub load true value;Based on main shaft displacement data and hub load true value, and in combination with the operation data of representative unit under multiple working conditions, mapping model is established by fitting operation, that is, the same model common experience model representing the mapping relationship between main shaft displacement and hub load;Mapping model is deployed on the remaining wind turbine of same model with representative unit;Respectively obtain the main shaft displacement data of representative unit and the remaining wind turbine;Based on the main shaft displacement data of each wind turbine, the real-time hub load data of each wind turbine is calculated respectively using the deployed mapping model.The application can effectively avoid the problems of insufficient accuracy of traditional theoretical model calculation method, low reliability and high cost of direct measurement method.

Description

Technical Field

[0001] This invention relates to the technical field of wind turbine hub load monitoring, and in particular to a method and system for monitoring wind turbine hub load based on main shaft displacement. Background Technology

[0002] Currently, there are several main technical approaches to obtaining hub loads in wind turbine generators: The first is the direct measurement method, which involves directly installing strain gauges or other sensors on the rotating components of the main shaft to obtain the hub load, or permanently installing sensors at the roots of all blades. The hub load is calculated by real-time acquisition of blade root loads and coordinate transformation. While these two methods offer high accuracy, they require the deployment of expensive and complex sensing systems on each unit, resulting in extremely high overall costs and hindering large-scale deployment. The second method is the theoretical model derivation method, which involves measuring the main shaft displacement and deriving the hub load based on classical materials mechanics formulas. This method relies on a universally idealized physical model. However, the actual hub is a complex assembly, and its load response is influenced by numerous non-ideal factors such as main shaft bearing stiffness, assembly tolerances, and temperature changes, leading to discrepancies between the theoretical model and the actual situation, and limiting the calculation accuracy.

[0003] In summary, existing methods have shortcomings in terms of accuracy, reliability, and cost. Establishing and solidifying an empirical mapping model of "main shaft displacement-hub load" that accurately reflects the true mechanical characteristics of a specific unit, thereby avoiding the problems of insufficient accuracy of traditional theoretical model derivation methods and the low reliability and high cost of direct measurement methods, has become an urgent problem to be solved. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a method for monitoring the hub load of wind turbine generator sets based on the main shaft displacement, which can effectively avoid the problems of insufficient accuracy of traditional theoretical model deduction methods, low reliability of direct measurement methods, and high cost.

[0005] Another objective of this invention is to provide a hub load monitoring system for wind turbine generator sets based on main shaft displacement.

[0006] The objective of this invention is achieved through the following technical solution:

[0007] A method for monitoring hub load of a wind turbine generator based on main shaft displacement, comprising the following steps:

[0008] S1. Select at least one wind turbine generator set of the same type from the wind farm to be monitored as a representative unit;

[0009] S2. Obtain the main shaft displacement data and hub load true value representing the unit;

[0010] S3. Based on the main shaft displacement data and true value of hub load of the representative unit, and combined with the operating data of the representative unit under multiple working conditions, a common empirical model of the same model is established through fitting calculation to characterize the mapping relationship between main shaft displacement and hub load, namely the mapping model.

[0011] S4. Deploy the mapping model on other wind turbines of the same model as the representative unit in the wind farm;

[0012] S5. Obtain the main shaft displacement data of the representative unit and the remaining wind turbine units respectively;

[0013] S6. Based on the main shaft displacement data of each wind turbine generator set, the real-time hub load data of each wind turbine generator set is calculated using the deployed mapping model.

[0014] Furthermore, the main shaft displacement data is obtained by a main shaft displacement sensor installed on the front bearing housing of the wind turbine generator.

[0015] Furthermore, the main shaft displacement sensor is mounted on the front bearing housing via an adjustable bracket, which ensures that the probe of the main shaft displacement sensor is aligned with the surface to be measured on the main shaft of the wind turbine generator set. The adjustable bracket includes a fixed bracket and an adapter plate. One end of the fixed bracket is fixed to the front end face of the front bearing housing, and one end of the adapter plate is connected to the other end of the fixed bracket. The other end of the adapter plate is used to mount the main shaft displacement sensor.

[0016] Furthermore, the process of obtaining the true value of the hub load is as follows:

[0017] Deploy load truth acquisition sources on representative units;

[0018] The original hub load data in the rotating coordinate system is obtained through a load truth acquisition source;

[0019] The rotor rotation angle signal output by the proximity switch sensor and rotor azimuth angle sensor representing the unit is obtained to obtain the rotor rotation angle data representing the unit.

[0020] The wind turbine rotation angle data and the original hub load data in the rotating coordinate system of the representative unit are preprocessed, and the coordinate transformation is performed based on the preprocessed original hub load data and wind turbine rotation angle data to obtain the hub load data in the fixed coordinate system, which is the true value of the hub load.

[0021] Furthermore, the true load value acquisition source is a leaf root load sensor.

[0022] Furthermore, in step S3, after establishing a mapping model representing the mapping relationship between spindle displacement and hub load, it is determined whether to remove the load truth acquisition source according to the preset operation and maintenance strategy; if the determination result is yes, the load truth acquisition source is removed to recover hardware costs; if the determination result is no, the load truth acquisition source is retained.

[0023] Furthermore, the linear functional relationship of the mapping model is:

[0024] ;

[0025] in, This refers to real-time hub load data, specifically hub pitch moment. Main axis displacement data; and These are the coefficients of the mapping model determined through fitting operations, representing the intercept term and the linear coefficients, respectively. This represents the residual of the mapping model.

[0026] Furthermore, it also includes step S7, where the wind turbine generator control system performs pitch control on the wind turbine generator based on real-time hub load data.

[0027] Another objective of this invention is achieved through the following technical solution:

[0028] A hub load monitoring system for wind turbine generators based on main shaft displacement, used to implement the aforementioned method for monitoring hub loads of wind turbine generators based on main shaft displacement, includes:

[0029] The selection unit is used to select at least one wind turbine generator set of the same type from the wind farm to be monitored as a representative unit.

[0030] The acquisition unit is used to acquire the main shaft displacement data and hub load true value of the representative unit, as well as the main shaft displacement data of the representative unit and other wind turbine units.

[0031] The load calibration unit is used to establish a common empirical model of the same type of generator, namely the mapping model, based on the main shaft displacement data and the true value of the hub load of the representative unit, and combined with the operating data of the representative unit under multiple working conditions, through fitting calculations.

[0032] The load calculation unit is used to calculate the real-time hub load data of each wind turbine generator set based on the main shaft displacement data of each wind turbine generator set and using the deployed mapping model.

[0033] The control system is used to perform pitch control on the wind turbine generator based on real-time hub load data.

[0034] Furthermore, the acquisition unit includes a main shaft displacement sensor, a blade root load sensor, a proximity switch sensor, and a rotor azimuth angle sensor. The main shaft displacement sensor is used to acquire main shaft displacement data representing the turbine unit and other wind turbine units. The blade root load sensor is used to acquire raw hub load data in a rotating coordinate system. The proximity switch sensor and rotor azimuth angle sensor are used to acquire rotor rotation angle data representing the turbine unit. The rotor rotation angle data and raw hub load data in the rotating coordinate system of the representative turbine unit are preprocessed, and coordinate transformation is performed based on the preprocessed raw hub load data and rotor rotation angle data to obtain hub load data in a fixed coordinate system, which is the true value of the hub load.

[0035] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0036] 1. Reduced cost and complexity: This invention only requires temporary calibration on a few representative units, eliminating the need to install high-cost sensors on all units, which significantly reduces hardware costs and deployment complexity, while also achieving technical and economic efficiency.

[0037] 2. Improved installation and measurement accuracy: This invention improves the installation accuracy and engineering convenience of the sensor by using an adjustable bracket to install the spindle displacement sensor, ensuring the initial quality of data acquisition and providing a key guarantee for the accuracy of subsequent empirical models.

[0038] 3. Improved calculation accuracy: The common empirical model established in this invention is based on measured true values ​​and fully considers the common characteristics of the aircraft type. Compared with the universal physical model that does not consider the characteristics of the aircraft type, it effectively improves the accuracy and reliability of load estimation.

[0039] 4. Improved promotion efficiency: By establishing a unified model applicable to specific models, this invention achieves the technical effect of "one-time calibration, universal for the same model", which greatly improves the promotion and application efficiency of the load monitoring solution. Attached Figure Description

[0040] Figure 1 This is a flowchart of the method of the present invention.

[0041] Figure 2 This is a schematic diagram of the installation of the spindle displacement sensor in this invention.

[0042] Figure 3 This is a schematic diagram of the fixed bracket in this invention.

[0043] Figure 4 This is a schematic diagram of the adapter plate in this invention.

[0044] Figure 5 This is a system structure diagram of the present invention. Detailed Implementation

[0045] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0046] Example 1:

[0047] like Figure 1 As shown, this embodiment provides a method for monitoring the hub load of a wind turbine generator based on the main shaft displacement, including the following steps:

[0048] S1. Model calibration preparation stage: Select at least one wind turbine generator of the same type from the wind farm to be monitored as a representative unit and as the calibration object;

[0049] S2, Data Acquisition Stage: Acquire the main shaft displacement data and hub load true value of the representative unit; among which, the main shaft displacement data is acquired by the main shaft displacement sensor 101 installed on the front bearing housing 600 of the wind turbine generator set.

[0050] like Figures 2 to 4 As shown, to ensure the quality and alignment accuracy of the measurement signal, the spindle displacement sensor 101 is fixed to the front bearing housing 600 or other preset positions via an adjustable bracket 500 with attitude adjustment function. The adjustment function of the adjustable bracket 500 is used to precisely adjust the installation attitude of the spindle displacement sensor 101, ensuring that the probe of the spindle displacement sensor 101 is accurately aligned with the surface to be measured on the spindle and eliminating installation deviations. The adjustable bracket 500 includes a fixed bracket 501 and an adapter plate 502. One end of the fixed bracket 501 is fixed to the front end face of the front bearing housing 600, and one end of the adapter plate 502 is connected to the other end of the fixed bracket 501. The other end is used to install the spindle displacement sensor 101. During installation, the fixed bracket 501 is first rigidly connected to the front bearing housing 600 as a stable mounting base. Then, the adapter plate 502 carrying the spindle displacement sensor 101 is installed onto the fixed bracket 501.

[0051] The process of obtaining the true value of the hub load is as follows:

[0052] A load truth acquisition source is deployed on the representative unit. In this embodiment, the load truth acquisition source is the blade root load sensor 104.

[0053] The original hub load data in the rotating coordinate system is obtained through a load truth acquisition source;

[0054] The wind turbine rotation angle signal output by the proximity switch sensor 102 and the wind turbine azimuth angle sensor 103 representing the unit is acquired to obtain the wind turbine rotation angle data representing the unit.

[0055] The wind turbine rotation angle data and the original hub load data in the rotating coordinate system of the representative unit are preprocessed, and the coordinate transformation is performed based on the preprocessed original hub load data and wind turbine rotation angle data to obtain the hub load data in the fixed coordinate system, which is the true value of the hub load, specifically the true value of the hub pitch moment.

[0056] S3. Model Construction Stage: Based on the main shaft displacement data and true values ​​of hub loads of the representative unit, and combined with the operating data of the representative unit under multiple operating conditions (such as different wind speeds, rotational speeds, and wind shear conditions), a common empirical model for the same type of unit is established through fitting calculations. This embodiment uses the least squares method to characterize the mapping relationship between main shaft displacement and hub load; this is the mapping model. The specific form of the common empirical model for the same type of unit can be flexibly selected according to actual engineering needs, testing objectives, and the required estimation accuracy. In this embodiment, a linear regression model is used to balance computational efficiency and ease of engineering deployment. At this point, the common empirical model for the same type of unit is specifically represented by a linear function relationship, which is as follows:

[0057] ;

[0058] in, This refers to real-time hub load data, specifically hub pitch moment. Main axis displacement data; and These are the coefficients of the mapping model determined through fitting operations. For the constant intercept term of the mapping model, The linear influence weight of the main shaft displacement on the hub pitch moment; For mapping model residuals;

[0059] Once the parameters are determined, the calibration is complete. Then, based on the preset operation and maintenance strategy, it is determined whether to remove the load truth acquisition source. If the determination result is yes, the load truth acquisition source is removed to recover hardware costs. If the determination result is no, the load truth acquisition source is retained.

[0060] S4. Model Deployment Phase: Deploy the mapping model on the remaining wind turbines of the same model as the representative unit in the wind farm.

[0061] S5. Real-time data acquisition stage: Acquire the main shaft displacement data of the representative unit and other wind turbine units respectively.

[0062] S6. Load Calculation Stage: Based on the main shaft displacement data of each wind turbine generator set, the real-time hub load data of each wind turbine generator set is calculated using the deployed mapping model.

[0063] S7. Load Application Stage: The wind turbine generator control system 400 performs pitch control on the wind turbine generator based on real-time hub load data, thereby achieving effective management of the generator load.

[0064] Example 2:

[0065] like Figure 5 As shown, this embodiment provides a wind turbine hub load monitoring system based on main shaft displacement, used to implement the wind turbine hub load monitoring method based on main shaft displacement in Embodiment 1, including:

[0066] The selection unit (not shown in the figure) is used to select at least one wind turbine generator set of the same type from the wind farm to be monitored as a representative unit.

[0067] The acquisition unit is used to acquire the main shaft displacement data and hub load true value of the representative unit, as well as the main shaft displacement data of the representative unit and other wind turbine units.

[0068] The load calibration unit 200 is used to establish a common empirical model of the same model, namely the mapping model, based on the main shaft displacement data and the true value of the hub load of the representative unit, and combined with the operating data of the representative unit under multiple working conditions, through fitting calculations.

[0069] The load calculation unit 300 is used to calculate the real-time hub load data of each wind turbine generator set based on the main shaft displacement data of each wind turbine generator set and using the deployed mapping model.

[0070] The control system 400 is used to perform pitch control on the wind turbine generator set based on real-time hub load data.

[0071] Specifically, the acquisition unit includes a main shaft displacement sensor 101, a blade root load sensor 104, a proximity switch sensor 102, and a wind turbine azimuth angle sensor 103. The main shaft displacement sensor 101 is used to acquire the main shaft displacement data of the representative unit and other wind turbine generators. The blade root load sensor 104 is used to acquire the original hub load data in the rotating coordinate system. The proximity switch sensor 102 and the wind turbine azimuth angle sensor 103 are used to acquire the wind turbine rotation angle data of the representative unit. The wind turbine rotation angle data of the representative unit and the original hub load data in the rotating coordinate system are preprocessed, and coordinate transformation is performed based on the preprocessed original hub load data and wind turbine rotation angle data to obtain the hub load data in the fixed coordinate system, which is the true value of the hub load.

[0072] In the data input layer of this invention, the spindle displacement sensor 101 serves as the core sensing element of the system, responsible for real-time acquisition of the displacement change of the spindle. To ensure the quality and alignment accuracy of the measurement signal, the spindle displacement sensor 101 is fixed to the front bearing seat 600 or other preset positions by an adjustable bracket 500 with attitude adjustment function.

[0073] At the data processing level, the load calibration unit 200 is specifically responsible for processing the data stream during the calibration phase. It performs key fitting calculations to construct a "common experience model for the same model". The load calculation unit 300 plays a role in the application phase, responsible for substituting the real-time collected main shaft displacement data into the established mapping model to accurately calculate the real-time hub load data of each wind turbine.

[0074] At the data output level, the calculated real-time hub load data is sent to the control system 400 as the input basis for executing the independent pitch control strategy, thereby achieving effective management of the unit load.

[0075] This invention creatively employs a "substitution calibration" strategy, selecting a representative unit of the same turbine model for short-term high-precision calibration to establish a universal model, thus replacing the high-cost method of calibrating each unit individually. This method utilizes a data source collaboration mechanism, employing a temporarily deployed blade root load sensor 104 as the ground truth acquisition source, synchronously collecting data with the permanently installed main shaft displacement sensor 101 to construct a training set. Combined with the assistance of a proximity switch sensor 102 and a rotor azimuth sensor 103, a rigorous coordinate system transformation is performed, converting the original hub load data in the rotating coordinate system to hub load data in the stationary hub coordinate system, ensuring a physical correspondence with the main shaft displacement data. Based on this, this invention uses a multiple linear regression algorithm to construct a common empirical model for the same turbine model, establishing a strong correlation between main shaft displacement and hub load (especially pitch moment), ultimately achieving low-cost deployment. This allows other units of the same turbine model to achieve high-precision monitoring without installing expensive load sensors, relying solely on displacement data and this common model.

[0076] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope disclosed in the present invention, based on the technical solution and inventive concept of the present invention, shall fall within the scope of protection of the present invention.

Claims

1. A method for monitoring hub load of a wind turbine generator set based on main shaft displacement, characterized in that: Including steps, S1. Select at least one wind turbine generator set of the same type from the wind farm to be monitored as a representative unit; S2. Obtain the main shaft displacement data and hub load true value representing the unit; S3. Based on the main shaft displacement data and true value of hub load of the representative unit, and combined with the operating data of the representative unit under multiple working conditions, a common empirical model of the same model is established through fitting calculation to characterize the mapping relationship between main shaft displacement and hub load, namely the mapping model. S4. Deploy the mapping model on other wind turbines of the same model as the representative unit in the wind farm; S5. Obtain the main shaft displacement data of the representative unit and the remaining wind turbine units respectively; S6. Based on the main shaft displacement data of each wind turbine generator set, the real-time hub load data of each wind turbine generator set is calculated using the deployed mapping model.

2. The method for monitoring hub load of a wind turbine generator based on main shaft displacement according to claim 1, characterized in that: Main shaft displacement data is obtained by a main shaft displacement sensor installed on the front bearing housing of the wind turbine generator set.

3. The method for monitoring hub load of a wind turbine generator based on main shaft displacement according to claim 2, characterized in that: The main shaft displacement sensor is mounted on the front bearing housing via an adjustable bracket. The adjustable bracket ensures that the probe of the main shaft displacement sensor is aligned with the surface to be measured on the main shaft of the wind turbine generator set. The adjustable bracket includes a fixed bracket and an adapter plate. One end of the fixed bracket is fixed to the front end face of the front bearing housing, and one end of the adapter plate is connected to the other end of the fixed bracket. The other end of the adapter plate is used to mount the main shaft displacement sensor.

4. The method for monitoring hub load of a wind turbine generator based on main shaft displacement according to claim 1, characterized in that, The process of obtaining the true value of the hub load is as follows: Deploy load truth acquisition sources on representative units; The original hub load data in the rotating coordinate system is obtained through a load truth acquisition source; The wind turbine rotation angle signal output by the proximity switch sensor and the wind turbine azimuth angle sensor representing the unit is obtained to obtain the wind turbine rotation angle data representing the unit. The wind turbine rotation angle data and the original hub load data in the rotating coordinate system of the representative unit are preprocessed, and the coordinate transformation is performed based on the preprocessed original hub load data and wind turbine rotation angle data to obtain the hub load data in the fixed coordinate system, which is the true value of the hub load.

5. The method for monitoring hub load of a wind turbine generator based on main shaft displacement according to claim 4, characterized in that: The true load value acquisition source is a leaf root load sensor.

6. The method for monitoring hub load of a wind turbine generator based on main shaft displacement according to claim 4, characterized in that: In step S3, after establishing a mapping model that characterizes the mapping relationship between spindle displacement and hub load, it is determined whether to remove the load true value acquisition source according to the preset operation and maintenance strategy. If the judgment result is yes, then the load truth acquisition source is removed to recover hardware costs; If the judgment result is negative, the true value acquisition source of the load is retained.

7. The method for monitoring hub load of a wind turbine generator based on main shaft displacement according to claim 4, characterized in that: The linear functional relationship of the mapping model is: ； in, This refers to real-time hub load data, specifically hub pitch moment. Main axis displacement data; and These are the coefficients of the mapping model determined through fitting operations, representing the intercept term and the linear coefficients, respectively. This represents the residual of the mapping model.

8. The method for monitoring hub load of a wind turbine generator based on main shaft displacement according to claim 1, characterized in that: It also includes step S7, in which the wind turbine generator control system performs pitch control on the wind turbine generator based on real-time hub load data.

9. A hub load monitoring system for wind turbine generator sets based on main shaft displacement, characterized in that: A method for monitoring hub loads of a wind turbine generator set based on main shaft displacement, as described in any one of claims 1 to 8, includes: The selection unit is used to select at least one wind turbine generator set of the same type from the wind farm to be monitored as a representative unit. The acquisition unit is used to acquire the main shaft displacement data and hub load true value of the representative unit, as well as the main shaft displacement data of the representative unit and other wind turbine units. The load calibration unit is used to establish a common empirical model of the same type of generator, namely the mapping model, based on the main shaft displacement data and the true value of the hub load of the representative unit, and combined with the operating data of the representative unit under multiple working conditions, through fitting calculations. The load calculation unit is used to calculate the real-time hub load data of each wind turbine generator set based on the main shaft displacement data of each wind turbine generator set and using the deployed mapping model. The control system is used to perform pitch control on the wind turbine generator based on real-time hub load data.

10. A hub load monitoring system for wind turbine generator sets based on main shaft displacement according to claim 9, characterized in that: The acquisition unit includes a main shaft displacement sensor, a blade root load sensor, a proximity switch sensor, and a rotor azimuth angle sensor; the main shaft displacement sensor is used to acquire main shaft displacement data representing the unit and other wind turbine units; the blade root load sensor is used to acquire raw hub load data in a rotating coordinate system; the proximity switch sensor and the rotor azimuth angle sensor are used to acquire rotor rotation angle data representing the unit. The wind turbine rotation angle data and the original hub load data in the rotating coordinate system of the representative unit are preprocessed, and the coordinate transformation is performed based on the preprocessed original hub load data and wind turbine rotation angle data to obtain the hub load data in the fixed coordinate system, which is the true value of the hub load.

Images