Testing Method and Testing Device for Pitch Cylinders of Wind Turbines

Abstract

The present disclosure provides a test method and a test device for a pitch cylinder of a wind turbine generator. The test method includes: obtaining time-series load data of the wind turbine generator, where the time-series load data includes rotational torque and external wind load; performing simulation analysis on the time-series load data to obtain parameters during the full-life cycle operation of the pitch cylinder; and accelerating the pitch cylinder to operate under the parameters to determine whether the pitch cylinder meets the requirements for in-service operation. The test method and the test device according to the embodiments of the present invention can simulate various working conditions during the in-service operation of the wind turbine generator, and can perform effectiveness tests on the pitch cylinder, ensuring the reliability of the pitch cylinder.

Description

Technical Field

[0001] The present invention relates to the field of wind power, and more specifically, to a test method and a test device for a pitch cylinder of a wind turbine generator set. Background Art

[0002] The pitch system in a wind turbine generator set is mainly used to control the rotational speed of the impeller by controlling the angle of the blades, thereby controlling the output power of the wind turbine generator.

[0003] The reliable operation of the pitch cylinder, which is an indispensable component of the pitch system of the wind turbine generator set, is an important guarantee for the normal operation of the wind turbine generator set.

[0004] Taking a 6MW offshore wind turbine generator set as an example, the service life requirement of the pitch cylinder is 25 years. The newly designed pitch cylinder has not been fully tested, resulting in batch replacement of the cylinder due to leakage, and the direct economic loss may reach 200,000 yuan per unit.

[0005] In order to avoid similar problems, it is required that the technology readiness level reaches TRL6 before hanging up. However, the domestic technical research on pitch cylinders is basically in a blank state, and there is no unified design and test standard in the industry. How to test and ensure the reliability of the pitch cylinder throughout its life cycle has become an industry problem that needs to be solved urgently.

[0006] At present, there is no mature solution. Existing cylinder manufacturers conduct tests according to existing experience, which is far from the actual working conditions of the wind turbine generator set and cannot fully test and demonstrate. Summary of the Invention

[0007] One object of the present invention is to provide a test method and a test device capable of testing the reliability of a pitch cylinder.

[0008] One object of the present invention is to provide a test device and a test method capable of simulating the service conditions or service environment of a pitch cylinder and determining whether the pitch cylinder meets the service requirements.

[0009] According to one aspect of the present invention, there is provided a test method for a pitch cylinder of a wind turbine generator set, the test method comprising: obtaining time-series load data of the wind turbine generator set, the time-series load data including rotational torque and external wind load; performing simulation analysis on the time-series load data to obtain parameters during the full life cycle operation of the pitch cylinder; and causing the pitch cylinder to operate at an accelerated speed under the parameters to determine whether the pitch cylinder meets the requirements for in-service operation.

[0010] According to an embodiment of the present invention, the above method may further include obtaining structural parameters of the pitch bearing, and the steps of performing simulation analysis on the time-series load data to obtain parameters during the full life cycle operation of the pitch cylinder include: calculating the pitch driving torque based on the structural parameters and the time-series load data, and the structural parameters may include the friction coefficient, the swivel diameter, and the preloading friction torque; performing low-pass filtering with a specific time constant on the pitch driving torque to obtain parameters during the full life cycle operation of the pitch cylinder.

[0011] According to an embodiment of the present invention, the time-series load data may be the time-series load data of the blade root, and the parameters during the full life cycle operation include: the lower limit of the ultimate load of the full life cycle of the pitch cylinder, the running mileage of the full life cycle of the pitch cylinder, and the fatigue life of the full life cycle of the pitch cylinder.

[0012] According to an embodiment of the present invention, perform first-order low-pass filtering with a specific time constant on the time series with the highest load in the pitch driving torque to obtain parameters during the full life cycle operation of the pitch cylinder.

[0013] According to an embodiment of the present invention, the step of accelerating the operation of the pitch cylinder under the parameters may include at least one of the following steps: applying the lower limit of the ultimate load to the pitch cylinder to test whether the strength of the pitch cylinder meets the requirements, or applying a load to the pitch cylinder to break it and comparing the breaking value with the lower limit value of the ultimate bearing capacity to test whether the strength of the pitch cylinder meets the requirements; accelerating the operation of the pitch cylinder for the running mileage of the full life cycle to test whether the seals of the pitch cylinder are worn out; performing pulse pressure loading test on the inner cavity of the pitch cylinder to test whether the fatigue life of the pitch cylinder meets the requirements; moving the pitch cylinder within a predetermined range to judge whether the anti-wear ability of the pitch cylinder meets the requirements.

[0014] According to another aspect of the present invention, there is provided a test device for a pitch cylinder of a wind turbine generator, including: a time-series load data acquisition unit configured to acquire the time-series load data of the blade root of the wind turbine generator, and the time-series load data may include the rotational torque and the external wind load; a load processing and analysis module configured to perform simulation analysis on the time-series load data to obtain parameters during the full life cycle operation of the pitch cylinder; a test module configured to accelerate the operation of the pitch cylinder under the parameters to judge whether the pitch cylinder meets the requirements for in-service operation.

[0015] According to an embodiment of the present invention, the load processing and analysis module may be further configured to: calculate the pitch driving torque based on the structural parameters of the pitch bearing and the time-series load data; perform low-pass filtering with a specific time constant on the pitch driving torque to obtain parameters during the full life cycle operation of the pitch cylinder, and the structural parameters may include the friction coefficient, the swivel diameter, and the preloading friction torque.

[0016] According to an embodiment of the present invention, the time-series load data may be the time-series load data of the blade root, and the parameters during the full-life cycle operation may include: the lower limit of the ultimate load of the pitch cylinder during the full-life cycle, the running mileage of the pitch cylinder during the full-life cycle, and the fatigue life of the pitch cylinder during the full-life cycle.

[0017] According to an embodiment of the present invention, the load processing and analysis module may be further configured to: perform a first-order low-pass filter with a specific time constant on the time series with the highest load in the pitch driving torque to obtain the parameters during the full-life cycle operation of the pitch cylinder.

[0018] According to an embodiment of the present invention, the test module may include at least one of the following modules: an ultimate load test module, which applies the lower limit of the ultimate load to the pitch cylinder to test whether the strength of the pitch cylinder meets the requirements, or applies a load to the pitch cylinder to break it and compares the breaking value with the lower limit value of the ultimate bearing capacity to test whether the strength of the pitch cylinder meets the requirements; a full-life cycle stroke test module, which accelerates the pitch cylinder to run the running mileage during the full-life cycle to test whether the seals of the pitch cylinder are worn out; a fatigue test module, which performs a pulse pressure loading test on the inner cavity of the pitch cylinder to test whether the fatigue life of the pitch cylinder meets the requirements; a fretting wear test module, which moves the pitch cylinder within a predetermined range to determine whether the anti-fretting wear ability of the pitch cylinder meets the requirements. Description of the Drawings

[0019] Through the following detailed description in conjunction with the drawings, the objectives and features of the present invention will become clearer, where:

[0020] Figure 1 is a flowchart of a test method according to the first embodiment of the present invention;

[0021] Figure 2 is a flowchart of a test method according to the second embodiment of the present invention;

[0022] Figure 3 is a schematic diagram of a mechanical model according to an embodiment of the present invention;

[0023] Figure 4 is a curve graph showing the filtering of the pitch torque or the pitch driving torque;

[0024] Figure 5 is a block diagram of a test device according to an embodiment of the present invention;

[0025] Figure 6 is a block diagram of the specific configuration of a test module according to an embodiment of the present invention;

[0026] Figure 7 is the schematic diagram of the full life cycle stroke test module according to an embodiment of the present invention;

[0027] Figure 8 is the schematic diagram of the fatigue test module according to an embodiment of the present invention;

[0028] Figure 9 is the schematic diagram of the fretting wear test module according to an embodiment of the present invention. Specific embodiments

[0029] The test method and test device according to the embodiment of the present invention highly restore the wind power working conditions, perform targeted loading and action tests, and can customize the test boundary conditions in combination with the time-series load simulation analysis, fully simulating the operating conditions of the oil cylinder in the full life cycle.

[0030] The features of the examples described herein can be combined in various ways that will be apparent after understanding the disclosure of the present application, as long as the combination of these features does not violate the technical idea of the present invention and does not conflict with each other.

[0031] In addition, although the examples described herein have various configurations, other configurations that will be apparent after understanding the disclosure of the present application are also feasible.

[0032] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be noted that in the description and drawings of the following embodiments, the same reference numerals always denote the same components, and repeated descriptions are omitted.

[0033] The test method and test device according to the embodiment of the present invention can test the pitch oil cylinder for a wind turbine generator to determine whether the pitch oil cylinder meets the requirements for normal operation for a predetermined number of years in service.

[0034] Figure 1 is the flowchart of the test method according to the first embodiment of the present invention, Figure 2 is the flowchart of the test method according to the second embodiment of the present invention, Figure 3 is the schematic diagram of the mechanical model according to the embodiment of the present invention.

[0035] As Figure 1 shown, the test method according to the first embodiment of the present invention may include steps S110, S120, and S130.

[0036] In step S110, time-series load data of a wind turbine generator set is acquired. The time-series load data may be the time-series load of a pitch bearing or the time-series load data of the root of a blade of the wind turbine generator set. However, the present invention is not limited thereto. In other words, as long as the boundary conditions of the pitch cylinder (for example, the limit values of test data) can be calculated or obtained, the time-series load data is not specifically limited.

[0037] According to an embodiment of the present invention, the pitch torque of the pitch cylinder can be calculated based on the time-series load data, and various limit parameters of the pitch cylinder can be obtained based on the pitch torque (for example, time-series pitch torque).

[0038] For example, in step S120, simulation analysis is performed on the time-series load data to obtain parameters during the whole-life cycle operation of the pitch cylinder.

[0039] For example, a load package containing the following time-series load data can be input into the load directory of an analysis module (for example, the load processing and analysis module described below) in a certain format, so as to calculate the pitch torque based on various mechanical parameters and / or the structural parameters of the pitch bearing.

[0040] Furthermore, various boundary conditions (limit parameters) used in the test process of the pitch cylinder can be determined based on the pitch torque.

[0041] Specifically, based on the pitch torque data that changes with time, data such as the force, driving torque, flow rate at a predetermined pitch speed, mileage, number of pitch operations, etc. of the pitch cylinder under various working conditions can be obtained. Further, based on the proportion of the distribution of this working condition in the entire service life, various limit parameters of the pitch cylinder during the entire service cycle can be calculated.

[0042] As shown in Table 1 below, the time-series load data may include a rotational torque M xy and an external wind load M z , and may further include at least one of an axial component force F a and a radial component force F r . These parameters may be various parameters (for example, mechanical parameters) of the blade root or the pitch bearing as described above.

[0043] Table 1:

[0044]

[0045] In step S130, the pitch cylinder can be accelerated to operate under the above parameters (limit parameters) to determine whether the pitch cylinder meets the requirements for in-service operation.

[0046] In addition, the structural parameters of the pitch bearing can be obtained, and the pitch driving torque (or pitch torque) is calculated based on both the structural parameters of the pitch bearing and the time-series load data.

[0047] As Figure 2 shown, the test method according to the second embodiment of the present invention may include steps S210, S220, S230, S240, and S250.

[0048] In step S210, the time-series load data of the wind turbine generator set is obtained. As described above, the time-series load data may be the time-series load data of the pitch bearing.

[0049] In step S220, the structural parameters of the pitch bearing are obtained. The structural parameters of the pitch bearing can be obtained through actual measurement or can be determined in advance through its product parameters.

[0050] The structural parameters of the pitch bearing used in calculating the pitch driving torque are shown in Table 2:

[0051] Table 2:

[0052]

[0053] In step S230, the pitch driving torque is calculated based on the structural parameters and the time-series load data. The specific algorithm is not particularly limited.

[0054] The structural parameters of the pitch bearing may include the friction coefficient μ, the turning diameter d m and the preloading friction torque M pre and so on. The following takes Figure 3 as an example to describe the mechanical model according to the embodiment of the present invention, and the calculation method of the pitch torque or the pitch driving torque.

[0055] As Figure 3 shown, a three-dimensional coordinate system (XB, YB, and ZB) of the blade root is established. The direction from the blade tip to the hub is the ZB direction, the XB direction is parallel to the hub center axis, and the YB direction is perpendicular to the XB direction and the ZB direction respectively. M XB 、F XB 、M YB 、F YB 、M ZB 、F ZB are the torques and forces in the three wind directions of XB, YB, and ZB respectively.

[0056] The angular velocity of the blade rotation is ω, which is positive when rotating clockwise. M z and M f are the external wind load and the dynamic load friction torque respectively.

[0057] The dynamic load friction torque M fMainly related to the rotational torque M xy According to an embodiment of the present invention, the pitch driving torque or pitch torque can be obtained based at least on the time-series load data including the rotational torque M xy and the external wind load M z .

[0058] As an example, the pitch driving torque or pitch torque can be calculated based on the structural parameters of the pitch bearing and the time-series load data. For example, the dynamic load friction torque can be calculated by Equation 1 below:

[0059] M f = k1μ(M xy + F a × d m + k2× F r × d m ) + M pre (1)

[0060] Wherein, the meanings of μ, M xy , F a , d m , F r , d m , M pre are as described above, k1 and k2 are both constants, k 1 and k 2 can be empirical values and can be determined in advance. Equation 1 above is only an example of calculating the pitch driving torque or pitch torque, and the calculation can be performed by considering at least one of the friction coefficient, the turning diameter, and the preloaded friction torque in the structural parameters of the pitch bearing. As an example, the pitch torque can be calculated based on other similar mechanical models.

[0061] The hydraulic pitch system itself has no moment of inertia, and the moment of inertia of the blade itself can be considered in advance in other models (for example, the Blade model). Therefore, when calculating the pitch torque or pitch driving torque, only M z and M f need to be considered.

[0062] According to the three states of blade opening, feathering, and parking, a mechanical analysis and calculation of the pitch driving torque (pitch torque) required by the pitch system can be performed.

[0063] For example, when the pitch system is normally feathering, ω > 0. If the external wind load M z < 0 and greater than the friction torque, then the pitch cylinder only needs to provide a sufficient damping torque |M f | - |M z | (considering the direction).

[0064] Summarizing the analysis of each working condition, the detailed calculation can be shown in Table 3.

[0065] Table 3:

[0066]

[0067] In Table 3, M pitch represents the pitch torque or the corresponding pitch driving torque. When ω > 0, sign = +1; when ω < 0, sign = -1; when ω = 0, sign = 0.

[0068] M f can be calculated by Equation 1 above, which will not be elaborated here. Optionally, M f can also be calculated by other methods. For example, it can be calculated by only considering some structural parameters of the pitch bearing.

[0069] As Figure 2 shown, in step S240, a low-pass filter with a specific time constant is performed on the pitch driving torque to obtain the parameters during the full life cycle operation of the pitch cylinder. For example, a first-order low-pass filter with a specific time constant can be performed on the time series with the highest load in the pitch driving torque to obtain the parameters during the full life cycle operation of the pitch cylinder.

[0070] Specifically, a first-order low-pass filter with a certain time constant can be performed on the calculated pitch driving torque with time series characteristics.

[0071] As an example, the algorithm formula of the first-order low-pass filter can be Equation (2) below:

[0072] Y(n) = αX(n) + (1 - α)Y(n - 1) (2)

[0073] In Equation (2):

[0074] α is the filter coefficient, X(n) = the current sampling value, Y(n - 1) = the previous filtered output value, and Y(n) = the current filtered output value.

[0075] The first-order low-pass filter method weights the current sampling value and the previous filtered output value to obtain an effective filtered value, making the output have a feedback effect on the input.

[0076] The filter coefficient α can be determined by Equation (3) below:

[0077]

[0078] where Δt: the specific time constant, (where f is the sampling frequency).

[0079] The output value of the pitch driving torque after simulation filtering can reflect various parameters of the pitch cylinder during its entire life cycle (for example, the lower limit of the ultimate load of the pitch cylinder during its entire life cycle, the running mileage of the pitch cylinder during its entire life cycle, the fatigue life of the pitch cylinder during its entire life cycle, etc.), and provide the required data for each test module of the cylinder.

[0080] Figure 4 It is a curve graph showing the filtering of the pitch torque or the pitch driving torque;

[0081] As Figure 4 shown, the pitch driving torque changes with time. G1 is the curve of the original data without filtering, and G2, G3, and G4 are the curves of the output values after simulation filtering changing with time. Specifically, G2 is the curve of the output value changing with time when performing first-order low-pass filtering with a specific time constant (for example, 50 ms), G3 is the curve of the output value changing with time when performing first-order low-pass filtering with a specific time constant (for example, 150 ms), and G4 is the curve of the output value changing with time when performing first-order low-pass filtering with a specific time constant (for example, 350 ms).

[0082] By performing first-order low-pass filtering on the pitch driving torque with a specific time constant, various parameters of the pitch cylinder can be obtained more precisely (for example, the lower limit of the ultimate load of the pitch cylinder during its entire life cycle can be accurately extracted, the running mileage of the pitch cylinder during its entire life cycle can be calculated, the fatigue life of the pitch cylinder during its entire life cycle can be determined, etc.).

[0083] The steps of accelerating the pitch cylinder to run under parameters can include various test methods.

[0084] As an example, the lower limit of the ultimate load can be applied to the pitch cylinder to test whether the strength of the pitch cylinder meets the requirements, or a load can be applied to the pitch cylinder to break it and compare the breaking value with the lower limit value of the ultimate bearing to test whether the strength of the pitch cylinder meets the requirements. Specifically, it can be determined whether the pitch cylinder is normal by directly visually inspecting the external form of the pitch cylinder. If necessary, the pitch cylinder can be disassembled to visually inspect whether the internal components are damaged or there are cracks.

[0085] As an example, the pitch cylinder can be accelerated to run the running mileage of its entire life cycle to test whether the seals of the pitch cylinder are worn out.

[0086] As an example, pulse pressure loading test is performed on the inner cavity of the pitch cylinder to test whether the fatigue life of the pitch cylinder meets the requirements.

[0087] As an example, the pitch cylinder can be moved within a predetermined range (a small range) to determine whether the anti-wear ability of the pitch cylinder meets the requirements. The following will be described in detail in conjunction with Figure 5 and Figure 6 to describe these test modules in detail.

[0088] Figure 5 is a block diagram of a test device according to an embodiment of the present invention, Figure 6 is a block diagram of the specific configuration of a test module according to an embodiment of the present invention.

[0089] The test device according to an embodiment of the present invention may include a timing load data acquisition unit 100, a load processing and analysis module 200, and a test module 300.

[0090] The timing load data acquisition unit 100 can acquire the timing load data of the wind turbine generator. The timing load data can also be the timing load of the pitch bearing, or the timing load data of the root of the blade of the wind turbine generator. However, the present invention is not limited thereto. In other words, as long as the boundary conditions of the pitch cylinder (for example, the limit value of the test data) can be calculated or obtained, the timing load data is not specifically limited.

[0091] The load processing and analysis module 200 can perform simulation analysis on the timing load data to obtain the parameters during the full life cycle operation of the pitch cylinder.

[0092] The load processing and analysis module 200 can calculate the pitch driving torque based on the structural parameters of the pitch cylinder and the timing load data, and perform low-pass filtering with a specific time constant on the pitch driving torque to obtain the parameters during the full life cycle operation of the pitch cylinder.

[0093] A load packet containing the following timing load data can be input into the load directory of the load processing and analysis module 200 in a certain format, so that the load processing and analysis module 200 calculates the pitch torque based on various mechanical parameters and / or the structural parameters of the pitch bearing. The structural parameters can include the friction coefficient, the turning diameter, and the preloading frictional torque of the pitch bearing.

[0094] The timing load data can be the timing load data of the blade root or the pitch bearing. The timing load data can include the rotational torque M xy and the external wind load M z , and can also include at least one of the axial component force F a , the radial component force F r . These parameters can be the respective parameters (for example, mechanical parameters) of the blade root or the pitch bearing as described above. The specific calculation method can be as described above and will not be elaborated here.

[0095] The load processing and analysis module 200 can perform first-order low-pass filtering with a specific time constant on the time series of the pitch driving torque with the highest load to obtain the parameters during the full life cycle operation of the pitch cylinder. The parameters here may include: the lower limit of the ultimate load in the full life cycle of the pitch cylinder, the running mileage in the full life cycle of the pitch cylinder, the fatigue life in the full life cycle of the pitch cylinder, etc.

[0096] The load processing and analysis module 200 can perform simulation filtering on the calculated pitch driving torque, and its output value can reflect various parameters of the pitch cylinder during the full life cycle (for example, the lower limit of the ultimate load in the full life cycle of the pitch cylinder, the running mileage in the full life cycle of the pitch cylinder, the fatigue life in the full life cycle of the pitch cylinder, etc.), providing the required data for each test module of the pitch cylinder.

[0097] The test module 300 can accelerate the operation of the pitch cylinder under parameters (limit parameters) to determine whether the pitch cylinder meets the requirements for in-service operation.

[0098] As Figure 6 shown, the test module 300 may include at least one of an ultimate load test module 301, a full life cycle stroke test module 302, a fatigue test module 303, and a fretting wear test module 304.

[0099] The ultimate load test module 301 can apply the lower limit of the ultimate load to the pitch cylinder to test whether the strength of the pitch cylinder meets the requirements, or apply a load to the pitch cylinder to break it and compare the breaking value with the lower limit value of the ultimate bearing capacity to test whether the strength of the pitch cylinder meets the requirements.

[0100] Specifically, the ultimate load test module 301 can use two ultra-high pressure cylinders to perform a breaking test on the tested cylinder, and monitor the pressure change during the breaking process through the pressure sensor of the loading cylinder to test the ultimate bearing capacity of the tested cylinder.

[0101] Furthermore, the measured breaking value can be compared with the result of the time series load analysis to determine whether the index is qualified. As an example, data such as the breaking position and failure mode of the tested cylinder will be applied to the design review and optimization of the cylinder.

[0102] The full life cycle stroke test module 302 can accelerate the operation of the pitch cylinder for the running mileage in the full life cycle to test whether the seals of the pitch cylinder are worn out.

[0103] The fatigue test module 303 can perform pulse pressure loading test on the inner cavity of the pitch cylinder to test whether the fatigue life of the pitch cylinder meets the requirements.

[0104] The fretting wear test module 304 can move the pitch cylinder within a predetermined range to determine whether the anti-fretting wear ability of the pitch cylinder meets the requirements. The specific implementation methods of the full life cycle stroke test module 302, the fatigue test module 303, and the fretting wear test module 304 will be described in detail below.

[0105] Figure 7 is a schematic diagram of the full life cycle stroke test module according to an embodiment of the present invention. Figure 8 is a schematic diagram of the fatigue test module according to an embodiment of the present invention. Figure 9 is a schematic diagram of the fretting wear test module according to an embodiment of the present invention.

[0106] The full life cycle stroke test module 302 can control the oil inlet and oil return of the two chambers of the pitch cylinder through a hydraulic circuit, thereby realizing the rapid extension and retraction of the pitch cylinder, testing the dynamic wear performance of dynamic seals such as piston seals and rod seals, and then determining whether the life of the dynamic seal meets the requirements. The life judgment is equivalent and compared according to the results of the time-sequence load simulation analysis.

[0107] As Figure 7 shown, the full life cycle stroke test module 302 may include an oil supply and return unit 10, a valve unit 20, and a pitch cylinder 30.

[0108] The oil supply and return unit 10 may include common components such as a common hydraulic oil tank, a driving pump, and an overflow valve. The valve unit 20 may include various directional valves. The oil supply and return unit 10 can supply hydraulic oil in the hydraulic oil tank to the small chamber of the pitch cylinder 30, and the oil supply direction is direction A. At the same time, the hydraulic oil in the large chamber of the pitch cylinder 30 flows back to the hydraulic oil tank of the oil supply and return unit 10 through the valve unit 20, and the oil return direction is direction B.

[0109] In addition, when it is necessary to supply oil to the large chamber, the oil supply and return unit 10 can supply hydraulic oil in the hydraulic oil tank to the large chamber of the pitch cylinder 30, and the oil supply direction is direction D. At the same time, the hydraulic oil in the small chamber of the pitch cylinder 30 flows back to the hydraulic oil tank of the oil supply and return unit 10 through the valve unit 20, and the oil return direction is direction C.

[0110] Therefore, the full life cycle stroke test module 302 controls the oil inlet and oil return of the large chamber and the small chamber of the pitch cylinder through a hydraulic circuit, thereby realizing the rapid extension and retraction of the cylinder, accelerating the full life cycle running and mileage of the pitch cylinder, and testing whether the seals of the pitch cylinder are worn out. The pitch cylinder can be disassembled to visually distinguish whether the seals are damaged.

[0111] The above hydraulic oil circuit of the full life cycle stroke test module 302 is only an example and is not limited to a specific structure. In addition, the above hydraulic oil circuit may further include other auxiliary components.

[0112] As Figure 8 shown, the fatigue test module 303 may include an oil supply and return unit 10, a valve unit 20, a pitch cylinder 30, a first supercharger 41, and a second supercharger 42.

[0113] Similar to Figure 7 the description of similar components will be omitted. The oil supply and return unit 10 can supply hydraulic oil in the hydraulic oil tank to the large chamber of the pitch cylinder 30 via the valve unit 20 and the first supercharger 41, and the oil supply direction is direction A. At the same time, the hydraulic oil in the small chamber of the pitch cylinder 30 flows back to the hydraulic oil tank of the oil supply and return unit 10 via the second supercharger 42 and the valve unit 20, and the oil return direction is direction B.

[0114] In addition, the oil supply and return unit 10 can supply hydraulic oil in the hydraulic oil tank to the small chamber of the pitch cylinder 30 via the valve unit 20 and the second supercharger 42, and the oil supply direction is direction D. At the same time, the hydraulic oil in the large chamber of the pitch cylinder 30 flows back to the hydraulic oil tank of the oil supply and return unit 10 via the first supercharger 41 and the valve unit 20, and the oil return direction is direction C.

[0115] The fatigue test module 303 can fix both ends of the pitch cylinder on the tooling bench and perform an alternating pulse pressure test on the pressure output by the simulation results of the rod chamber and the rodless chamber. The number of pulse cycles is the equivalent fatigue load number output by the time-series load simulation analysis, and the frequency can be 1 Hz.

[0116] Similarly, the above hydraulic oil circuit of the fatigue test module 303 is only an example and is not limited to a specific structure. In addition, the above hydraulic oil circuit may also include other auxiliary components.

[0117] As Figure 9 shown, the fretting wear test module 304 may include an oil supply and return unit 10, a valve unit 20, and a pitch cylinder 30. The structure of the fretting wear test module 304 may be similar to that of the full life cycle stroke test module 302, which will not be elaborated here.

[0118] The fretting wear test module 304 can simulate the working conditions of a wind turbine generator operating in a small angle or a local angle range for a long time through a hydraulic oil circuit, and can verify whether it will cause problems such as abnormal wear of the cylinder seal due to poor lubrication.

[0119] The fretting wear test module 304 can install both ends of the pitch cylinder on the tooling bench. This tooling bench allows the cylinder to have a small displacement of 0-x, and the x value is given according to the seal structure design and the wind power working conditions, and corresponding tests are carried out to evaluate its anti-fretting wear ability.

[0120] The above hydraulic oil circuit of the fretting wear test module 304 is only an example and is not limited to a specific structure. Additionally, the above hydraulic oil circuit may further include other auxiliary components.

[0121] It should be noted that some components (such as the oil supply and return unit) in the above full-life cycle stroke test module 302, fatigue test module 303, and fretting wear test module 304 can be shared.

[0122] The pitch cylinder test method and test device according to the embodiments of the present invention can directly convert the time-series load data of the blade into the design input and test boundary parameters of the pitch cylinder, facilitating the test of whether the pitch cylinder meets the requirements.

[0123] The pitch cylinder test method and test device according to the embodiments of the present invention can simulate various working conditions during the in-service operation of the wind turbine generator set and can conduct an effectiveness test on the pitch cylinder, ensuring the reliability of the pitch cylinder.

[0124] The test method and test device according to the embodiments of the present invention fill the industry gap.

[0125] The above is only the preferred embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any change or replacement that is easily conceivable by those skilled in the art within the technical scope disclosed by the present invention should be covered by the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claimed rights.

Claims

1. A testing method for a pitch cylinder of a wind turbine generator, characterized in that, the testing method includes: obtaining the time-series load data of the wind turbine generator, where the time-series load data includes rotational torque and external wind load; performing simulation analysis on the time-series load data to obtain parameters during the full life cycle operation of the pitch cylinder; accelerating the operation of the pitch cylinder under the parameters to determine whether the pitch cylinder meets the requirements for in-service operation, wherein, the testing method further includes obtaining the structural parameters of the pitch bearing, the step of performing simulation analysis on the time-series load data to obtain parameters during the full life cycle operation of the pitch cylinder includes: calculating the pitch driving torque based on the structural parameters and the time-series load data, performing low-pass filtering with a specific time constant on the pitch driving torque to obtain parameters during the full life cycle operation of the pitch cylinder.

2. The testing method for a pitch cylinder of a wind turbine generator according to claim 1, characterized in that, the structural parameters include friction coefficient, swing diameter and preloading frictional torque.

3. The testing method for a pitch cylinder of a wind turbine generator according to claim 2, characterized in that, the time-series load data is the time-series load data at the blade root, and the parameters during the full life cycle operation include: the lower limit of the ultimate load during the full life cycle of the pitch cylinder, the running mileage during the full life cycle of the pitch cylinder, and the fatigue life during the full life cycle of the pitch cylinder.

4. The testing method for a pitch cylinder of a wind turbine generator according to claim 3, characterized in that, performing first-order low-pass filtering with a specific time constant on the time series with the highest load in the pitch driving torque to obtain parameters during the full life cycle operation of the pitch cylinder.

5. The testing method for a pitch cylinder of a wind turbine generator according to claim 3, characterized in that, the step of accelerating the operation of the pitch cylinder under the parameters includes at least one of the following steps: applying the lower limit of the ultimate load to the pitch cylinder to test whether the strength of the pitch cylinder meets the requirements, or applying a load to the pitch cylinder to break it and comparing the breaking value with the lower limit value of the ultimate load-bearing to test whether the strength of the pitch cylinder meets the requirements; accelerating the operation of the pitch cylinder for the running mileage during the full life cycle to test whether the seals of the pitch cylinder are worn out; performing pulse pressure loading test on the inner cavity of the pitch cylinder to test whether the fatigue life of the pitch cylinder meets the requirements; moving the pitch cylinder within a predetermined range to determine whether the anti-wear ability of the pitch cylinder meets the requirements.

6. A testing device for a pitch cylinder of a wind turbine generator, characterized in that, includes: a time-series load data acquisition unit configured to acquire the time-series load data of the wind turbine generator, where the time-series load data includes rotational torque and external wind load; a load processing and analysis module configured to perform simulation analysis on the time-series load data to obtain parameters during the full life cycle operation of the pitch cylinder; The test module is configured to accelerate the pitch cylinder to operate under the parameters to determine whether the pitch cylinder meets the requirements for in-service operation. Wherein, the load processing and analysis module is further configured to: calculate the pitch driving torque based on the structural parameters of the pitch bearing and the time-series load data; perform low-pass filtering with a specific time constant on the pitch driving torque to obtain the parameters during the full life cycle operation of the pitch cylinder.

7. The test device for the pitch cylinder of a wind turbine according to claim 6, Characterized in that The structural parameters include the friction coefficient, the turning diameter, and the preloading friction torque.

8. The test device for the pitch cylinder of a wind turbine according to claim 7, Characterized in that The time-series load data is the time-series load data at the blade root, and the parameters during the full life cycle operation include: the lower limit of the ultimate load of the full life cycle of the pitch cylinder, the running-in mileage of the full life cycle of the pitch cylinder, and the fatigue life of the full life cycle of the pitch cylinder.

9. The test device for the pitch cylinder of a wind turbine according to claim 8, Characterized in that The load processing and analysis module is further configured to: perform first-order low-pass filtering with a specific time constant on the time series with the highest load in the pitch driving torque to obtain the parameters during the full life cycle operation of the pitch cylinder.

10. The test device for the pitch cylinder of a wind turbine according to claim 9, Characterized in that The test module includes at least one of the following modules: The ultimate load test module applies the lower limit of the ultimate load to the pitch cylinder to test whether the strength of the pitch cylinder meets the requirements, or applies a load to the pitch cylinder to break it and compares the breaking value with the lower limit value of the ultimate load-bearing to test whether the strength of the pitch cylinder meets the requirements; The full life cycle stroke test module accelerates the pitch cylinder to operate the running-in mileage of the full life cycle to test whether the seals of the pitch cylinder are worn out; The fatigue test module performs pulse pressure loading tests on the inner cavity of the pitch cylinder to test whether the fatigue life of the pitch cylinder meets the requirements; The fretting wear test module moves the pitch cylinder within a predetermined range to determine whether the anti-fretting wear ability of the pitch cylinder meets the requirements.

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