Method for condition assessment of a wind turbine, controller and wind turbine

Abstract

The present disclosure provides a wind turbine unit state evaluation method, a controller and a wind turbine unit. The state evaluation method comprises: obtaining a blade root bending moment of the wind turbine unit; obtaining an aerodynamic torque according to the blade root bending moment; obtaining an impeller absorbed power based on a product of the aerodynamic torque, an impeller rotating speed of the wind turbine unit and a predetermined blade absorbed efficiency; obtaining a first power according to a product of the impeller absorbed power and a predetermined unit efficiency; and evaluating a state of the wind turbine unit according to a product of the first power and an actual output power or a grid-connected power of the wind turbine unit. The state evaluation method according to the embodiment of the present disclosure can determine whether the unit has an abnormal state of too much energy accumulation.

Description

Technical Field

[0001] This disclosure generally relates to the field of wind power, and more specifically, to a condition assessment method for wind turbine generators, a controller, and a wind turbine generator. Background Technology

[0002] The installed capacity of wind farms is increasing year by year, their distribution is becoming more widespread, and wind power accounts for a larger proportion of electricity generation, gradually becoming a conventional energy source. Monitoring the operating status of wind turbine generators (also known as wind turbines, units, or wind turbine units) to obtain operating status data allows for precise protection and control based on the high-precision measured data. Furthermore, condition monitoring or condition assessment provides a reliable basis for the safety control and stability evaluation of wind turbine generators.

[0003] Currently, operating status data such as unit speed, vibration, and power are obtained by installing sensors on core components such as impellers, blades, nacelles, towers, generators, and gearboxes. Although high-precision sensors and algorithms can accurately obtain unit status data, the actual power absorbed by the impeller from the wind is generally assessed using impeller speed, impeller moment of inertia, generator electromagnetic torque, and the efficiency of the entire transmission chain. This assessment method assumes that all energy absorbed by the impeller, except for power grid transmission, is used for impeller acceleration or deceleration, making it impossible to know whether other equipment bears this energy and suffers damage. Existing power prediction and assessment methods can be found in two Chinese patent documents with publication numbers CN109783828A and CN102693457A.

[0004] In addition, the aerodynamic torque Ta can be calculated by taking wind speed, air density, and blade length, and then multiplied by the impeller speed to obtain the wind energy absorbed by the impeller. However, the instability of wind speed and the tower shadow effect lead to certain deviations in the estimation of aerodynamic torque. Summary of the Invention

[0005] One of the objectives of the exemplary embodiments disclosed herein is to provide a state assessment method capable of determining whether the state of a wind turbine generator set is abnormal.

[0006] According to a first aspect of this disclosure, a method for assessing the condition of a wind turbine generator set includes: obtaining the blade root bending moment of the wind turbine generator set; obtaining the aerodynamic torque based on the blade root bending moment; obtaining the rotor absorbed power based on the product of the aerodynamic torque, the rotor speed of the wind turbine generator set, and the blade absorption efficiency; obtaining a first power based on the product of the rotor absorbed power and the unit efficiency; and assessing the condition of the wind turbine generator set based on the first power and the actual output power or grid-connected power of the wind turbine generator set.

[0007] According to embodiments of this disclosure, the step of obtaining the blade root bending moment of a wind turbine generator set may include: obtaining a first drive current of a first pitch motor of the wind turbine generator set; obtaining a first motor drive torque based on the first drive current and a first current-torque coefficient ratio of the first pitch motor; obtaining a first blade root bending moment of the wind turbine generator set based on the product of the first motor drive torque, the mechanical efficiency of the first pitch motor, the mechanical transmission efficiency of the first pitch motor, and the reduction ratio of the first pitch reducer; and determining the blade root bending moment based on the first blade root bending moment.

[0008] According to embodiments of this disclosure, the first pitch mechanical transmission efficiency can be determined by the product of the rotational efficiency of the first pitch reducer and the transmission efficiency of the first pitch reducer.

[0009] According to an embodiment of this disclosure, the step of determining the blade root bending moment based on the first blade root bending moment includes: obtaining the second blade root bending moment and the third blade root bending moment of the wind turbine generator set respectively; calculating the average value of the first blade root bending moment, the second blade root bending moment and the third blade root bending moment, and using the average value as the blade root bending moment.

[0010] According to embodiments of this disclosure, the step of obtaining aerodynamic torque based on blade root bending moment may include: obtaining aerodynamic torque based on the product of blade root bending moment and correction coefficient.

[0011] According to embodiments of this disclosure, the correction coefficient can be obtained by measuring the first aerodynamic torque of the wind turbine prototype using a torque sensor and obtaining the average root bending moment of the three blades of the wind turbine prototype; performing curve fitting or linear regression analysis on the first aerodynamic torque and the average root bending moment to obtain the correction coefficient.

[0012] According to embodiments of this disclosure, the unit efficiency can be determined by multiplying the generator mechanical efficiency, generator electrical efficiency, electrical transmission chain efficiency, and mechanical transmission chain efficiency of the wind turbine generator set.

[0013] According to embodiments of this disclosure, the condition assessment method may further include: obtaining the tip speed ratio, blade simulation parameters, and pitch angle of the wind turbine generator set, and determining the blade absorption efficiency based on the tip speed ratio, blade simulation parameters, pitch angle, and a pre-determined blade absorption efficiency model.

[0014] According to embodiments of this disclosure, the step of assessing the state of a wind turbine generator set based on a first power and the actual output power or grid-connected power of the wind turbine generator set may include: determining that the wind turbine generator set is in an abnormal state in response to the absolute value of the difference between the first power and the actual output power or grid-connected power being greater than or equal to a first predetermined threshold and lasting for a first predetermined time, or the absolute value being greater than or equal to a second predetermined threshold, less than the first predetermined threshold, and lasting for a second predetermined time, wherein the first predetermined threshold is greater than the second predetermined threshold, and the first predetermined time is less than the second predetermined time.

[0015] According to a second aspect of this disclosure, a computer-readable storage medium stores instructions or programs that, when executed by a processor, implement the aforementioned method for assessing the condition of a wind turbine generator set.

[0016] According to a third aspect of this disclosure, a condition assessment device for a wind turbine generator set includes: a blade root bending moment acquisition unit for acquiring the blade root bending moment of the wind turbine generator set; a first calculation unit for acquiring aerodynamic torque based on the blade root bending moment; a second calculation unit for acquiring rotor absorbed power based on the product of aerodynamic torque, rotor speed of the wind turbine generator set, and blade absorption efficiency; a third calculation unit for acquiring a first power based on the product of rotor absorbed power and generator set efficiency; and an assessment unit for assessing the condition of the wind turbine generator set based on the first power and the actual output power or grid-connected power of the wind turbine generator set.

[0017] According to a fourth aspect of this disclosure, a controller for a wind turbine generator set includes: a processor and a computer-readable storage medium, the computer-readable storage medium storing a program or instructions that, when executed by the processor, implement the aforementioned wind turbine generator set state assessment method.

[0018] According to a fifth aspect of this disclosure, a wind turbine generator set includes: the aforementioned condition assessment device or the aforementioned controller.

[0019] Based on the principle of energy conservation, this disclosure compares the calculated power with the generated power to predict in advance whether a large amount of energy is accumulating inside the unit, thereby avoiding excessive energy accumulation inside the unit that could cause local overheating or mechanical damage.

[0020] Further aspects and / or advantages of the general concept of the invention will be set forth in part in the description which follows, and in part will be obvious from the description or may be learned by practice of the general concept of the invention. Attached Figure Description

[0021] The above and other objects and features of exemplary embodiments of this disclosure will become clearer from the following description taken in conjunction with the accompanying drawings, which exemplarily illustrate the embodiments, wherein:

[0022] Figure 1 This is a flowchart illustrating a state assessment method according to a first embodiment of the present disclosure;

[0023] Figure 2 This is a flowchart illustrating a state assessment method according to a second embodiment of the present disclosure;

[0024] Figure 3 This is a flowchart illustrating a state assessment method according to a third embodiment of the present disclosure;

[0025] Figure 4 This is a graph showing the absorption efficiency of the blade according to the fourth embodiment of the present disclosure;

[0026] Figure 5 This is a block diagram illustrating a state assessment apparatus according to a first embodiment of the present disclosure;

[0027] Figure 6 This is a block diagram illustrating a controller according to a first embodiment of the present disclosure. Detailed Implementation

[0028] The following detailed description is provided to aid in obtaining a full understanding of the methods, apparatus, and / or systems described herein. However, the order of operations described herein is merely illustrative and is not limited to those orders set forth herein; equivalent substitutions or changes may be made, except for operations that must occur or be performed in a specific order. Furthermore, for clarity and conciseness, descriptions of content well-known in the art will be omitted or simplified.

[0029] Unless otherwise defined, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains upon understanding this disclosure. Unless expressly defined herein, terms (such as those defined in a general dictionary) shall be interpreted as having a meaning consistent with their meaning in the context of the relevant field and in this disclosure, and shall not be interpreted in an idealized or overly formalistic manner.

[0030] Unless otherwise specified, the same reference numerals generally refer to the same elements (e.g., components, steps, and methods). Reference numerals described in previous embodiments that reappear in later embodiments may be omitted. Furthermore, technical features described in different or the same embodiments can be combined in any way, as long as the combined embodiment or technical solution is complete and can solve the technical problem of this application or achieve the technical effects described or not described in this application but which can be determined based on the complete technical solution described above.

[0031] This disclosure determines the blade root bending moment M based on the pitch system. z The leaf root bending moment M z (For example, the root bending moment M of three blades) z The average value of the power absorbed by the impeller is combined with other parameters of the unit to obtain the impeller absorbed power. Under normal circumstances, considering the efficiency of the whole machine, the power absorbed by the unit (i.e., the impeller absorbed power) should match the power generated. If the impeller absorbed power is significantly higher than the power generated for a long time, there may be a component or some components in the unit that are subjected to excessive energy, which may lead to damage to these components.

[0032] This disclosure obtains the aerodynamic bending moment based on the blade root bending moment, and estimates the unit's output power or generating power based on the aerodynamic bending moment, impeller speed, and unit efficiency. The estimated output power or generating power is then compared with the actual generating power to determine if there is an abnormality of excessive energy accumulation within the unit. If such an abnormality is confirmed, the unit can be shut down for further inspection. The following will combine... Figures 1 to 6 Specific embodiments of this disclosure are described below.

[0033] Figure 1 This is a flowchart illustrating a state assessment method according to a first embodiment of the present disclosure. Figure 2 This is a flowchart illustrating a state assessment method according to a second embodiment of the present disclosure. Figure 3 This is a flowchart illustrating a state assessment method according to a third embodiment of the present disclosure. Figure 4 This is a graph showing the absorption efficiency of the blade according to the fourth embodiment of the present disclosure.

[0034] Reference Figure 1 The state assessment method according to the first embodiment of the present disclosure may include steps S110, S120, S130, S140 and S150.

[0035] In step S110, the blade root bending moment M of the wind turbine generator is obtained. z .

[0036] The inner ring of the pitch bearing of a wind turbine generator set can be connected to the drive motor of the pitch system, and the outer ring of the pitch bearing can be connected to the root of the blade (i.e., the blade root). As an example, the blade root bending moment M can be measured by a sensor. z .

[0037] Measuring the leaf root bending moment M z When it is inconvenient to install the sensor, the blade root bending moment M can be determined by the drive current of the pitch motor. z .

[0038] Specifically, refer to Figure 3 The step S110 of obtaining the blade root bending moment of the wind turbine generator set may include: step S111, step S112, step S113 and step S114.

[0039] A wind turbine generator set may include three pitch motors: a first pitch motor that drives the first blade to pitch, a second pitch motor that drives the second blade to pitch, and a third pitch motor that drives the third blade to pitch.

[0040] In step S111, the first drive current of the first pitch motor of the wind turbine generator set is obtained.

[0041] The first drive current of the first pitch motor can be obtained by installing a corresponding current sensor, or it can be obtained directly from the detection parameters of the relevant sensors of the original pitch controller, or converted based on the detection parameters.

[0042] In step S112, the first motor drive torque T is obtained based on the ratio of the first drive current to the first current torque coefficient of the first pitch motor. p .

[0043] The current-torque ratios (first, second, and third) of each pitch motor can be pre-calibrated. In other words, the ratio between the pitch motor's drive current and torque (the current-torque ratio) can be predetermined. Therefore, the motor drive torque T of each pitch motor can be obtained given the known pitch drive current and current-torque ratios. p .

[0044] In step S113, based on the first motor drive torque T p The mechanical efficiency η of the first pitch motor p First pitch mechanical transmission efficiency Ratio P The first blade root bending moment of the wind turbine generator is obtained by multiplying the first pitch reducer reduction ratio i by itself. For details, please refer to equation (1) below.

[0045] M z =η p * T p Ratio P * i (1)

[0046] In step S114, the blade root bending moment is determined based on the first blade root bending moment.

[0047] As an example, the first blade root bending moment can be directly determined as the blade root bending moment of the wind turbine generator.

[0048] Alternatively, the blade root bending moment can be obtained based on the second and third pitch motors. For example, the second blade root bending moment of the wind turbine can be obtained by multiplying the second motor's drive torque, the second pitch motor's mechanical efficiency, the second pitch mechanical transmission efficiency, and the second pitch reducer's reduction ratio. Of course, the third blade root bending moment of the wind turbine can also be obtained in a similar manner.

[0049] The blade root moment of a wind turbine can be determined based on the second and / or third blade root moments. It can be determined by averaging at least two of the first, second, and third blade root moments, and the resulting average value is used as the blade root moment of the wind turbine. For example, the blade root moment can be the average of the root moments of the three blades.

[0050] The pitch motor mechanical efficiency η associated with the pitch system for each blade p Pitch mechanical transmission efficiency Ratio P The reduction ratio i of the pitch reducer can be directly determined based on the parameters of the corresponding pitch system. In other words, the mechanical efficiency η of the pitch motor... p Pitch mechanical transmission efficiency Ratio P The reduction ratio i of the pitch reducer can be predetermined.

[0051] The pitch mechanical transmission efficiency can be determined by multiplying the rotational efficiency of the pitch reducer by its transmission efficiency. Specifically, the pitch mechanical transmission efficiency (e.g., the rotational efficiency of the first pitch reducer corresponding to the first pitch motor) can be directly determined as the product of the rotational efficiency of the pitch reducer (e.g., the rotational efficiency of the first pitch reducer corresponding to the first pitch motor) and its transmission efficiency (e.g., the transmission efficiency of the first pitch reducer corresponding to the first pitch motor). The second pitch mechanical transmission efficiency can also be determined based on the product of the rotational efficiency of the second pitch reducer corresponding to the second pitch motor and its transmission efficiency. The third pitch mechanical transmission efficiency can be determined in a similar manner.

[0052] Reference Figure 1 In step S120, the aerodynamic torque is obtained based on the blade root bending moment.

[0053] The steps for obtaining aerodynamic torque based on blade root bending moment may include: obtaining aerodynamic torque T by multiplying the blade root bending moment by a correction factor C. a The specific method of obtaining it is shown in equation (2) below.

[0054] T a =C * M z (2)

[0055] The correction factor can be a predetermined constant, and the correction factor C can be obtained based on a prototype wind turbine generator. Specifically, it can be obtained in the following ways:

[0056] The first aerodynamic torque of the wind turbine prototype is measured by a torque sensor, and the average root bending moment of the three blades of the wind turbine prototype is obtained. Then, curve fitting or linear regression analysis is performed on the first aerodynamic torque and the average root bending moment to obtain the correction coefficient C.

[0057] In other words, the functional relationship between aerodynamic torque and blade root bending moment can be obtained in advance. Given the blade root bending moment, the aerodynamic torque can be directly obtained by combining this functional relationship, without needing to calculate the aerodynamic torque T based on blade wind speed, air density, blade length, etc. aThis reduces the impact of wind speed instability and tower shadow effect on calculation accuracy.

[0058] Furthermore, the condition assessment method of this disclosure does not require the installation of a torque sensor for each wind turbine, thereby reducing costs. On the other hand, the aerodynamic torque T of this disclosure... a The bending moment M at the leaf root z The converted leaf root bending moment M z The value is calculated from the drive current of the pitch motor, so there is no need to install a sensor to measure the blade root bending moment.

[0059] Reference Figure 1 In step S130, based on the aerodynamic torque T a The rotor speed (Ω) and blade absorption efficiency (C) of the wind turbine generator set. p The product of these three factors yields the impeller absorption power P1.

[0060] As an example, the aerodynamic torque T can be directly expressed as... a The rotor speed Ω of the wind turbine generator set and the predetermined blade absorption efficiency C p The product of these three factors is determined as the impeller absorption power P1. The specific calculation method is shown in equation (3) below.

[0061] P1 = Ω * T a *C p (3)

[0062] The impeller speed Ω can be obtained through relevant sensors. Regarding the blade absorption efficiency C... p The blade absorption efficiency C can be determined based on a pre-defined blade absorption efficiency model. This model can be based on the tip speed ratio, blade simulation parameters, and blade pitch angle. The blade absorption efficiency C can be determined using the obtained tip speed ratio, blade simulation parameters, blade pitch angle, and the pre-defined blade absorption efficiency model. p .

[0063] Therefore, the state assessment method according to the embodiments of this disclosure may further include the steps of obtaining the tip speed ratio, blade simulation parameters (including blade airfoil, length, etc.) and pitch angle of the wind turbine generator set.

[0064] The tip speed ratio can be determined by the ratio of the blade tip speed (which can be calculated from the impeller speed and blade length) to the wind speed (which can be measured by the crosswind system). The blade simulation parameters can be determined based on the actual physical parameters of the blade. The pitch angle can be obtained from the rotary encoder or from the control commands of the pitch system.

[0065] For details, please refer to Figure 4 ,from Figure 4It is possible to obtain the same airfoil, the same tip speed ratio, and different blade pitch angles (0°, 2°, 3°, etc.) for the same blade absorption efficiency, as well as the same airfoil, the same blade pitch angle, and different tip speed ratios for the same blade absorption efficiency.

[0066] In step S140, the first power P2 is obtained by multiplying the impeller absorbed power and the unit efficiency η. Specifically, it can be obtained by the following equation (4):

[0067] P2 = η * P1 (4)

[0068] In other words, the product of the impeller absorption power P1 and the predetermined unit efficiency η can be directly determined as the first power P2. The first power P2 can be understood as the theoretical power. If the first power P2 is much greater than the generating power, it indicates that a large amount of energy has accumulated in the unit.

[0069] Specifically, in step S150, the status of the wind turbine generator set is evaluated based on the first power and the actual output power or grid-connected power of the wind turbine generator set.

[0070] As an example, the ratio of the first power P2 to the actual output power or grid-connected power P of the wind turbine generator set can be used to determine whether the wind turbine generator set is in an abnormal state where a large amount of energy has accumulated in the unit.

[0071] Specifically, when the ratio is greater than or equal to a first threshold and lasts for a first time, or when the ratio is greater than or equal to a second threshold, less than the first threshold, and lasts for a second time, the wind turbine generator is determined to be in an abnormal state, wherein the first threshold is greater than the second threshold, and the first time is less than the second time.

[0072] In other words, when the ratio is large (e.g., greater than 1.1 and less than 1.2) and the duration is long, the wind turbine generator can be determined to be in an abnormal state. Conversely, when the ratio is even larger (e.g., greater than or equal to 1.2) but the duration is short, the wind turbine generator can also be determined to be in an abnormal state.

[0073] Alternatively, the difference between the first power P2 and the actual output power or grid-connected power P of the wind turbine generator can be used to determine this. (Refer to...) Figure 2 Step S150 may include steps S151 and S152.

[0074] In step S151, it is determined whether the absolute value |ΔP| of the difference between the first power and the actual output power or grid-connected power is greater than or equal to a first predetermined threshold P. t1 And continue for the first predetermined time T1, or determine whether the absolute value |ΔP| is greater than or equal to the second predetermined threshold P. t2 Less than the first predetermined threshold P t1And it continues for a second predetermined time T2, wherein the first predetermined threshold P t1 Greater than the second predetermined threshold P t2 The first scheduled time T1 is less than the second scheduled time T2.

[0075] In step S152, if the above conditions are met, it can be determined that the wind turbine generator set is in an abnormal state.

[0076] In other words, the step of assessing the state of the wind turbine generator based on the first power and the actual output power or grid-connected power of the wind turbine generator includes: responding to the absolute value of the difference between the first power and the actual output power or grid-connected power, |ΔP|, being greater than or equal to a first predetermined threshold P. t1 And it continues for a first predetermined time T1, or the absolute value is greater than or equal to a second predetermined threshold P. t2 Less than the first predetermined threshold P t1 And for a second predetermined time T2, it is determined that the wind turbine generator is in an abnormal state, wherein the first predetermined threshold P t1 Greater than the second predetermined threshold P t2 The first scheduled time T1 is less than the second scheduled time T2.

[0077] When it is determined that the wind turbine is in the above-mentioned abnormal state, the wind turbine can be shut down, and further inspection can be conducted to determine which components of the wind turbine have accumulated energy (for example, by observing the heat).

[0078] The aforementioned unit efficiency η can be determined by multiplying the generator mechanical efficiency, generator electrical efficiency, electrical drive chain efficiency, and mechanical drive chain efficiency of the wind turbine generator set. The generator mechanical efficiency, generator electrical efficiency, electrical drive chain efficiency, and mechanical drive chain efficiency can all be determined based on the electrical parameters of the relevant components of the unit; that is, all four can be predetermined.

[0079] Figure 5 This is a block diagram illustrating a state assessment apparatus according to a first embodiment of the present disclosure. Figure 6 This is a block diagram illustrating a controller according to a first embodiment of the present disclosure.

[0080] Reference Figure 5 The state assessment device 500 according to the first embodiment of the present disclosure may include: a blade root bending moment acquisition unit 510, a first calculation unit 520, a second calculation unit 530, a third calculation unit 540, and an assessment unit 550.

[0081] The blade root bending moment acquisition unit 510 can obtain the blade root bending moment of the wind turbine generator set. As mentioned above, the blade root bending moment acquisition unit 510 can be determined based on the motor drive bending moment, which can be calculated based on the drive current of the pitch motor.

[0082] Specifically, the blade root bending moment acquisition unit 510 can be configured to: obtain the first drive current of the first pitch motor of the wind turbine generator set; obtain the first motor drive torque based on the first drive current and the first current-torque coefficient ratio of the first pitch motor; obtain the first blade root bending moment of the wind turbine generator set based on the product of the first motor drive torque, the predetermined mechanical efficiency of the first pitch motor, the predetermined mechanical transmission efficiency of the first pitch motor, and the predetermined reduction ratio of the first pitch reducer; and determine the blade root bending moment based on the first blade root bending moment.

[0083] The blade root bending moment acquisition unit 510 can directly determine the first blade root bending moment as the blade root bending moment of the wind turbine generator set. As an example, the blade root bending moment acquisition unit 510 can use the average value of the first blade root bending moment, the second blade root bending moment, and the third blade root bending moment as the blade root bending moment of the wind turbine generator set.

[0084] The blade root moment acquisition unit 510 can be configured to obtain the aerodynamic torque based on the product of the blade root moment and a predetermined correction coefficient. Specifically, the blade root moment acquisition unit can measure the first aerodynamic torque of the wind turbine prototype using a torque sensor and obtain the average blade root moment of the three blades of the wind turbine prototype. Curve fitting or linear regression analysis is then performed on the first aerodynamic torque and the average blade root moment to obtain the correction coefficient. The blade root moment and aerodynamic torque can also be calibrated to form a mapping table, allowing the aerodynamic torque to be determined by looking up the table when the blade root moment is known. Similarly, the blade root moment can be obtained in a similar manner, determining the blade root moment by looking up a table when the motor drive current is known.

[0085] The first calculation unit 520 can obtain the aerodynamic torque based on the blade root bending moment. The first calculation unit 520 can determine the aerodynamic torque based on the product of the blade root bending moment and the correction coefficient.

[0086] The second calculation unit 530 can obtain the impeller absorption power based on the product of aerodynamic torque, impeller speed of wind turbine generator set and predetermined blade absorption efficiency.

[0087] The third calculation unit 540 can obtain the first power based on the product of the impeller absorbed power and the predetermined unit efficiency.

[0088] As an example, the calculation steps of equations (1) to (4) as described above can be performed by a single computing unit, and equations (1) to (4) can be combined to obtain the first power. The unit efficiency can be determined by multiplying the predetermined mechanical efficiency of the wind turbine generator, the predetermined electrical efficiency of the generator, the predetermined electrical drive chain efficiency, and the predetermined mechanical drive chain efficiency. As an example, the unit efficiency can be directly determined by multiplying the above four factors.

[0089] The evaluation unit 550 can evaluate the status of the wind turbine generator set based on the first power and the actual output power or grid-connected power of the wind turbine generator set.

[0090] Specifically, the evaluation unit 550 can be configured to respond to the absolute value |ΔP| of the difference between the first power and the actual output power or grid-connected power being greater than or equal to a first predetermined threshold P. t1 And it continues for a first predetermined time T1, or the absolute value is greater than or equal to a second predetermined threshold P. t2 Less than the first predetermined threshold P t1 And for a second predetermined time T2, it is determined that the wind turbine generator is in an abnormal state, wherein the first predetermined threshold P t1 Greater than the second predetermined threshold P t2 The first scheduled time T1 is less than the second scheduled time T2.

[0091] In other words, when the absolute value mentioned above is large and the duration is long, it can be determined that the wind turbine generator is in an abnormal state. Conversely, when the absolute value mentioned above is even larger but the duration is short, it can also be determined that the wind turbine generator is in an abnormal state. The threshold or predetermined threshold mentioned above can be greater than the generator's self-consumption power (its own power consumption (e.g., the sum of the power consumption of the pitch system, crosswind system, etc.)).

[0092] It should be understood that the various units or modules in the control apparatus according to the exemplary embodiments of this disclosure may be implemented as hardware components and / or software components. Those skilled in the art can implement the various units, for example, using field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), software algorithms, etc., depending on the processes performed by each defined unit.

[0093] Each of the above steps can be programmed as a software program or instruction. Therefore, the control method according to the exemplary embodiments of this disclosure can be implemented via software. The computer-readable storage medium of the exemplary embodiments of this disclosure can store a computer program that, when executed by a processor, implements the state evaluation method as described in the exemplary embodiments above.

[0094] According to various embodiments of this disclosure, apparatus (e.g., modules or their functions) or methods can be implemented by programs or instructions stored in a computer-readable storage medium. When such instructions are executed by a processor, the processor can perform a function corresponding to the instruction or perform a method corresponding to the instruction. At least a portion of a module can be implemented (e.g., executed) by a processor. At least a portion of a programmed module can include modules, programs, routines, instruction sets, and procedures for performing at least one function. In one example, the instructions or software include machine code (such as machine code generated by a compiler) that is directly executed by one or more processors or computers. In another example, the instructions or software include higher-level code that is executed by one or more processors or computers using an interpreter. Instructions or software can be written using any programming language based on the block diagrams and flowcharts shown in the accompanying drawings and the corresponding description in the specification.

[0095] Computer-readable storage media include non-transitory computer-readable storage media, such as magnetic media like floppy disks and magnetic tapes, optical media (including optical disc (CD) ROMs and DVD ROMs), magneto-optical media like flexible optical discs, hardware devices such as ROMs and RAMs designed for storing and executing program instructions, and flash memory. The program instructions include language code executable by a computer using an interpreter and machine language code generated by a compiler. The aforementioned hardware devices can be implemented by one or more software modules for performing the operations of the various embodiments of this disclosure.

[0096] The modules or programming modules disclosed herein may include at least one of the aforementioned components, with some components omitted or others added. The operations of the modules, programming modules, or other components may be executed sequentially, in parallel, cyclically, or probingly. Furthermore, some operations may be executed in a different order, may be omitted, or may be extended with other operations.

[0097] The computer-readable storage medium and / or condition assessment apparatus of exemplary embodiments of this disclosure may be part of the controller (e.g., main controller) of a wind turbine generator set.

[0098] For example, refer to Figure 6 The controller 600 according to an exemplary embodiment of the present disclosure may include a processor 620 and a computer-readable storage medium 630, wherein the computer-readable storage medium 630 stores a computer program or instructions that, when executed by the processor 620, implement the state evaluation method as described in the exemplary embodiment above.

[0099] The wind turbine generator sets of embodiments of this disclosure may include the computer-readable storage medium, condition assessment device, or controller described above.

[0100] The condition assessment method and condition assessment device according to the embodiments of this disclosure can accurately determine whether a wind turbine generator set has an abnormal state of energy accumulation.

[0101] The condition assessment method and condition assessment apparatus according to the embodiments of this disclosure do not require blade root bending moment sensors, etc., which can reduce costs.

[0102] Based on the principle of energy conservation, this disclosure compares the calculated power with the generated power to predict in advance whether a large amount of energy is accumulating inside the unit, thus avoiding local overheating or mechanical damage caused by excessive energy accumulation inside the unit.

[0103] While some exemplary embodiments of this disclosure have been shown and described, those skilled in the art will understand that modifications may be made to these embodiments without departing from the principles and spirit of this disclosure as defined by the claims and their equivalents. For example, technical features of different embodiments may be combined.

Claims

1. A condition assessment method for wind turbine generator sets, characterized in that, include: Obtain the blade root bending moment of the wind turbine generator set; The aerodynamic torque is obtained based on the blade root bending moment; The impeller absorption power is obtained by multiplying the aerodynamic torque, the impeller speed of the wind turbine generator set, and the blade absorption efficiency. The first power is obtained by multiplying the impeller absorption power and the unit efficiency; Based on the first power and the actual output power or grid-connected power of the wind turbine generator set, determine whether the wind turbine generator set is in an abnormal state of energy accumulation. The step of determining whether the wind turbine is in an abnormal state of energy accumulation based on the first power and the actual output power or grid-connected power of the wind turbine includes: In response to the absolute value of the difference between the first power and the actual output power or the grid-connected power being greater than or equal to a first predetermined threshold and lasting for a first predetermined time, or the absolute value being greater than or equal to a second predetermined threshold, less than the first predetermined threshold, and lasting for a second predetermined time, it is determined that the wind turbine generator set is in an abnormal state of energy accumulation, wherein the first predetermined threshold is greater than the second predetermined threshold, and the first predetermined time is less than the second predetermined time.

2. The condition assessment method for wind turbine generator sets according to claim 1, characterized in that, The steps for obtaining the blade root bending moment of the wind turbine generator set include: Obtain the first drive current of the first pitch motor of the wind turbine generator set; The first motor drive torque is obtained based on the first drive current and the first current-torque coefficient ratio of the first pitch motor. The first blade root bending moment of the wind turbine is obtained by multiplying the first motor drive torque, the first pitch motor mechanical efficiency, the first pitch mechanical transmission efficiency, and the first pitch reducer reduction ratio. The blade root bending moment is determined based on the first blade root bending moment.

3. The condition assessment method for wind turbine generator sets according to claim 2, characterized in that, The first pitch mechanical transmission efficiency is determined by the product of the rotational efficiency of the first pitch reducer and the transmission efficiency of the first pitch reducer.

4. The condition assessment method for wind turbine generator sets according to claim 2, characterized in that, The steps for determining the blade root bending moment based on the first blade root bending moment include: The second and third blade root bending moments of the wind turbine generator set were obtained respectively. The average value of the first leaf root bending moment, the second leaf root bending moment, and the third leaf root bending moment is calculated, and the average value is taken as the leaf root bending moment.

5. The condition assessment method for wind turbine generator sets according to any one of claims 1 to 4, characterized in that, The step of obtaining the aerodynamic torque based on the blade root bending moment includes: obtaining the aerodynamic torque based on the product of the blade root bending moment and the correction coefficient.

6. The condition assessment method for wind turbine generator sets according to claim 5, characterized in that, The correction factor is obtained in the following way: The first aerodynamic torque of the wind turbine prototype was measured by a torque sensor, and the average root bending moment of the three blades of the wind turbine prototype was obtained. The correction coefficient is obtained by performing curve fitting or linear regression analysis on the first aerodynamic torque and the average value of the blade root bending moment.

7. The condition assessment method for wind turbine generator sets according to any one of claims 1 to 4, characterized in that, The unit efficiency is determined by the product of the generator mechanical efficiency, generator electrical efficiency, electrical transmission chain efficiency, and mechanical transmission chain efficiency of the wind turbine generator set.

8. The condition assessment method for wind turbine generator sets according to claim 7, characterized in that, The condition assessment method further includes: obtaining the tip speed ratio, blade simulation parameters, and pitch angle of the wind turbine generator set; and determining the blade absorption efficiency based on the tip speed ratio, the blade simulation parameters, the pitch angle, and a pre-determined blade absorption efficiency model.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores instructions or programs that, when executed by a processor, implement the condition assessment method for a wind turbine generator set according to any one of claims 1 to 8.

10. A condition assessment device for a wind turbine generator set, characterized in that, include: The blade root bending moment acquisition unit obtains the blade root bending moment of the wind turbine generator set. The first calculation unit obtains the aerodynamic torque based on the blade root bending moment; The second calculation unit obtains the rotor absorption power based on the product of the aerodynamic torque, the rotor speed of the wind turbine generator set, and the blade absorption efficiency. The third calculation unit obtains the first power based on the product of the impeller absorbed power and the unit efficiency; The evaluation unit determines whether the wind turbine is in an abnormal state of energy accumulation based on the first power and the actual output power or grid-connected power of the wind turbine. The evaluation unit is configured to determine that the wind turbine generator is in an abnormal state of energy accumulation in response to the absolute value of the difference between the first power and the actual output power or the grid-connected power being greater than or equal to a first predetermined threshold and lasting for a first predetermined time, or the absolute value being greater than or equal to a second predetermined threshold, less than the first predetermined threshold, and lasting for a second predetermined time. The first predetermined threshold is greater than the second predetermined threshold, and the first predetermined time is less than the second predetermined time.

11. A controller for a wind turbine generator set, characterized in that, The method includes a processor and a computer-readable storage medium storing a program or instructions that, when executed by the processor, implement the condition assessment method for a wind turbine generator set according to any one of claims 1 to 8.

12. A wind turbine generator set, characterized in that, Includes the condition assessment device according to claim 10 or the controller according to claim 11.

Images