Method and device for determining theoretical power of wind turbine generator

Abstract

According to the method and device for determining the theoretical power of the wind turbine generator set, a set theoretical power calculation scheme integrating multiple theoretical power calculation algorithms is provided from the power generation control principle of the wind turbine generator set, the method does not depend on a traditional scheme based on wind speed prediction, and the method and device have the advantages of being high in precision and accurate in calculation. The method for determining the theoretical power of the wind turbine generator comprises the steps that the current generator rotating speed and the variable pitch angle of the wind turbine generator are obtained; according to the rotating speed and the variable pitch angle of the generator, selecting a target determination curve matched with the rotating speed and the variable pitch angle of the generator from a plurality of pre-calibrated theoretical power determination curves, and determining theoretical power based on the target determination curve; wherein the pre-calibrated determination curve of the various theoretical powers is obtained through calibration according to historical operation data of the wind turbine generator.

Description

Technical Field

[0001] This application relates to the field of wind turbine generators, specifically a method and apparatus for determining the theoretical power of a wind turbine generator. Background Technology

[0002] The theoretical power of a wind turbine generator set is the theoretical output of the unit under specific operating conditions and wind resource conditions.

[0003] With the development of the domestic wind power market, wind power prices have evolved from grid parity for coal to market-based bidding. Accurate calculation of the theoretical power of wind turbines: 1) Helps wind farms formulate optimal bidding strategies, avoiding penalties (such as balancing mechanism fees) due to over- or under-generation, which is especially crucial in time-of-use pricing or spot markets. 2) Supports wind farms in participating in ancillary services such as frequency regulation and reserve capacity, enabling them to dynamically adjust output to meet grid demand and generate additional revenue.

[0004] Current theoretical power calculations are generally based on extrapolation from power curves.

[0005] The power curve represents the statistical relationship between wind speed and unit power at different levels. Typical power curves and scatter plots of power curves are shown below. Figure 1 As shown, due to factors such as turbulence, wake, flow, shear, and the operating lag of wind turbines, the power curve scatter points exhibit a wide range of characteristics, indicating that the relationship between wind speed and power is not a simple linear one. Therefore, using wind speed to estimate theoretical power based on the statistical results of the power curve results in uncertainties. Summary of the Invention

[0006] This application provides a method for determining the theoretical power of wind turbine units. Based on the power generation control principle of wind turbine units, it proposes a scheme for calculating the theoretical power of the unit by integrating multiple theoretical power calculation algorithms. This scheme does not rely on the traditional wind speed prediction-based scheme and has the characteristics of high accuracy and accurate calculation.

[0007] The technical solution of this invention is as follows: A method for determining the theoretical power of a wind turbine generator set, comprising: Obtain the current generator speed and pitch angle of the wind turbine; Based on the generator speed and pitch angle, a target determination curve matching the generator speed and pitch angle is selected from a variety of pre-calibrated theoretical power determination curves, and the theoretical power is determined based on the target determination curve. The pre-calibrated curves for determining various theoretical power values ​​are obtained based on historical operating data of the wind turbine.

[0008] Preferably, the step of selecting a target determination curve that matches the generator speed and the pitch angle from a variety of pre-calibrated theoretical power determination curves includes: When the generator speed is lower than the preset speed N1, the target determination curve is selected as the wind speed and power curve, and the theoretical power is directly obtained by interpolating the current generator wind speed on the wind speed and power curve. When the generator speed is in the first speed range, the target determination curve is selected as the pitch angle versus wind energy utilization coefficient curve. The wind energy utilization coefficient is obtained by interpolating the current pitch angle of the wind turbine on the pitch angle versus wind energy utilization coefficient curve. The theoretical input power is determined according to the ratio of the current output power of the wind turbine to the wind energy utilization coefficient. The theoretical power is determined according to the relationship between the theoretical input power and the theoretical output power. When the generator speed is in the second speed region, the target determination curve is selected as the generator speed and power curve, and the theoretical efficiency is obtained by interpolating the current generator speed on the generator speed and power curve. When the generator speed is in the third speed region or the pitch angle exceeds the preset angle, the target determination curves are selected as the pitch angle versus wind energy utilization coefficient curve and the wind speed versus wind energy curve. The wind energy utilization coefficient is obtained by interpolating the current pitch angle of the wind turbine on the pitch angle versus wind energy utilization coefficient curve. The theoretical input power is determined according to the ratio of the current output power of the wind turbine to the wind energy utilization coefficient. The theoretical power is determined according to the relationship between the theoretical input power and the theoretical output power. The first speed region, the second speed region, and the third speed region increase sequentially.

[0009] Preferably, the pre-calibrated curves for determining various theoretical power outputs are obtained during the calibration process based on historical operating data of the wind turbine generator set. Based on the historical operating data of the wind turbine units after anomaly screening, wind speed and power curves were constructed at intervals of 0.1 m / s; and generator speed and power curves and pitch angle and power curves were constructed at intervals of 50 kW respectively. Based on the pitch angle and power curve, determine the power corresponding to different pitch angles; Based on the power corresponding to different pitch angles, the wind energy utilization coefficient is determined to construct a pitch angle versus wind energy utilization coefficient curve.

[0010] A device for determining the theoretical power of a wind turbine, comprising: The acquisition module is used to obtain the current generator speed and pitch angle of the wind turbine. The theoretical power determination module is used to select a target determination curve that matches the generator speed and the pitch angle from a variety of pre-calibrated theoretical power determination curves, and determine the theoretical power based on the target determination curve; The pre-calibrated curves for determining various theoretical power values ​​are obtained based on historical operating data of the wind turbine.

[0011] Preferably, the theoretical power determination module includes: The first theoretical power determination unit is used to select the target determination curve as the wind speed and power curve when the generator speed is lower than the preset speed N1, and directly obtain the theoretical power by interpolating the current generator wind speed on the wind speed and power curve. The second theoretical power determination unit is used to select the target determination curves as the pitch angle versus wind energy utilization coefficient curve and the wind speed versus wind energy curve when the generator speed is in the first speed range. The wind energy utilization coefficient is obtained by interpolating the current pitch angle of the wind turbine on the pitch angle versus wind energy utilization coefficient curve. The theoretical input power is determined according to the ratio of the current output power of the wind turbine to the wind energy utilization coefficient. The theoretical power is determined according to the relationship between the theoretical input power and the theoretical output power. The third theoretical power determination unit is used to select the target determination curve as the generator speed and power curve when the generator speed is in the second speed region, and to obtain the theoretical efficiency by interpolating the current generator speed on the generator speed and power curve. The fourth theoretical power determination unit is used to select the target determination curves as the pitch angle versus wind energy utilization coefficient curve and the wind speed versus wind energy curve when the generator speed is in the third speed range or the pitch angle exceeds the preset angle. The wind energy utilization coefficient is obtained by interpolating the current pitch angle of the wind turbine on the pitch angle versus wind energy utilization coefficient curve. The theoretical input power is determined according to the ratio of the current output power of the wind turbine to the wind energy utilization coefficient. The theoretical power is determined according to the relationship between the theoretical input power and the theoretical output power. The second speed range, the third speed range, and the second speed range increase sequentially.

[0012] The beneficial effects of this invention are as follows: Based on the power generation control principle of wind turbine units, a theoretical power estimation scheme integrating multiple theoretical power estimation algorithms is proposed. This scheme does not rely on traditional wind speed prediction-based schemes and features high accuracy and precise calculation. Attached Figure Description

[0013] Figure 1 A comparison chart showing the variation of theoretical and actual power of wind turbines at different wind speeds; Figure 2 This is a flowchart illustrating the method for determining the theoretical power of a wind turbine in an embodiment of this application. Figure 3 This is a schematic diagram of the operation control area of ​​the generator set in the embodiments of this application; Figure 4 This is a schematic diagram of the generator speed and power curve constructed in the embodiments of this application; Figure 5 This is a schematic diagram of the pitch angle versus power curve constructed in the embodiments of this application; Figure 6 This is a schematic diagram of the pitch angle versus generator speed curve constructed in the embodiments of this application; Figure 7 This is a schematic diagram of the pitch angle versus wind energy utilization coefficient curve constructed in the embodiments of this application; Figure 8 This is a comparison chart of theoretical power and actual power in the embodiments of this application; Figure 9 This is a comparison chart of theoretical power and actual power in the embodiments of this application. Detailed Implementation

[0014] Reference Figure 3 In the embodiments of this application, the wind turbine operation control area is typically divided as follows: In the region near N1 (i.e., the first speed region), the pitch angle is at its minimum position (0 or close to 0). As the wind speed increases, the generator speed of the wind turbine remains constant, while the power gradually increases. N1 speed represents the minimum speed at which power generation is performed.

[0015] In the N1-Nr region (i.e., the second speed region), the generator speed and power of the wind turbine are linearly related in order to track the optimal wind energy utilization.

[0016] In the Nr region (i.e., the third speed region), the generator speed and power of the generator set are kept stable through pitch and power control. As the wind speed increases, the generator speed of the wind turbine remains constant, while the power gradually increases.

[0017] Based on the above principles, the theoretical power of the wind turbine can be calculated according to the relationship between the generator speed and power of the wind turbine in the embodiments of this application.

[0018] Furthermore, the wind energy utilization factor Cp can be expressed by the following formula: The wind energy utilization coefficient Cp is calculated, where ρ is the air density in kg / m3; P is the actual shaft power obtained by the wind turbine in W; s is the swept area of ​​the wind turbine in m2; and v is the actual wind speed in m / s.

[0019] The characteristics of a wind turbine are typically represented by a set of dimensionless performance curves for the power coefficient Cp. The wind energy utilization coefficient is a function of the tip speed ratio ψ and the pitch angle β of the wind turbine blades. The wind energy utilization coefficient Cp can be approximated by the following formula: It is evident that the wind energy utilization coefficient Cp is related to the tip speed ratio ψ and the pitch angle β of the wind turbine blades. When the generator speed remains constant, the wind energy utilization coefficient Cp exhibits a functional relationship with the pitch angle β.

[0020] In actual operation, the operating state differs from the design state due to external factors such as wind speed measurement, turbulence, and shear; the transmission efficiency of the unit itself; and the individual differences in installation and wind turbine units. Therefore, the design wind energy utilization coefficient is not entirely applicable to the evaluation of wind farms.

[0021] Here, we borrow the concept of wind energy utilization factor Cp, calculate and fit the wind energy utilization rate based on the wind speed measured by the unit, and then deduce the theoretical power.

[0022] The theoretical power is calculated based on the operating power curve.

[0023] This scheme mainly combines the above three calculation methods, updates the historical operation database of wind turbines in real time, constructs the required curves, and thus calculates the theoretical power.

[0024] Reference Figure 2 This application provides a method for determining the theoretical power of a wind turbine, including: S101, obtain the current generator speed and pitch angle of the wind turbine; S102, based on the generator speed and pitch angle, select a target determination curve that matches the generator speed and pitch angle from a variety of pre-calibrated theoretical power determination curves, and determine the theoretical power based on the target determination curve; The pre-calibrated curves for determining various theoretical power values ​​are obtained based on historical operating data of the wind turbine.

[0025] The pre-calibrated curves for various theoretical power outputs are obtained based on historical operating data of the wind turbine generators. This historical operating data includes the generator speed, output power, and wind speed. During the calibration process: Based on long-term historical operating data of wind turbines after filtering out abnormal conditions such as power limitation, such as more than 3 months of second-level data, the first curve between wind speed and turbine output power is constructed at an interval of 0.1 m / s; and the second curve between generator speed and turbine output power and the third curve between pitch angle and turbine output power are constructed at an interval of 50 kW. The unit output power corresponding to different pitch angles is determined based on the third curve between pitch angle and unit output power. Based on the turbine output power and wind speed corresponding to different pitch angles, the wind energy utilization factor Cp is determined, and a fourth curve relating the pitch angle and the wind energy utilization factor is constructed. Simultaneously, the turbine input power can be determined based on wind speed, thus establishing the correspondence between the turbine input power and the turbine output power.

[0026] Historical operating data includes instantaneous wind speed, instantaneous power, pitch angle, generator speed, and abnormal operating status indicators. All historical operating data is filtered to remove data indicating abnormal operating conditions or no power generation, retaining only data indicating normal power generation. The process of filtering out abnormal data is not an improvement in this application and will not be elaborated upon here.

[0027] When constructing the first curve, the 5-second average wind speed and 5-second average power are used as the wind speed and power values ​​corresponding to each point in the curve. The desired first curve is formed by fitting the curve using methods such as quadratic curve fitting.

[0028] Similarly, when constructing the second curve, the 5-second average generator speed and 5-second average power are used as the generator speed and power values ​​corresponding to each point on the curve. The desired second curve is formed by fitting the curve using methods such as quadratic curve fitting. Figure 4 .

[0029] Similarly, when constructing the third curve, the 5-second average pitch angle and 5-second average power are used as the pitch angle and power values ​​corresponding to each point on the curve. The desired third curve is formed by fitting the curve using methods such as quadratic curve fitting. Figure 5 .

[0030] After completing the third curve, the turbine output power corresponding to different pitch angles is determined by interpolation. Then, based on the turbine output power corresponding to different pitch angles, the wind energy utilization coefficient corresponding to different pitch angles is determined using the aforementioned theoretical calculation formula for the wind energy utilization coefficient. Finally, the result is fitted as shown below. Figure 7 The fourth curve shown.

[0031] Furthermore, in this embodiment of the application, in order to distinguish the specific values ​​of different speed ranges during subsequent theoretical power calculations, a system as follows was also constructed. Figure 6 The pitch angle versus generator speed curve shown is used to determine the relationship between the pitch angle and generator speed. Figure 3 The specific generator speed values ​​for the first speed range, the second speed range, and the third speed range are determined.

[0032] Furthermore, in this embodiment of the application, step S102, which selects a target determination curve that matches the generator speed and the pitch angle from a variety of pre-calibrated theoretical power determination curves based on the generator speed and the pitch angle, includes: S1021, when the generator speed is lower than the preset speed N1, the target determination curve is selected as the wind speed and power curve, and the theoretical power is directly obtained by interpolating the current generator wind speed on the wind speed and power curve; wherein, the preset speed N1 is the minimum speed for power generation operation; S1022, when the generator speed is in the first speed range. The target curve is selected as the pitch angle versus wind energy utilization coefficient curve. The wind energy utilization coefficient is obtained by interpolating the current pitch angle of the wind turbine on the pitch angle versus wind energy utilization coefficient curve. The theoretical input power is determined according to the ratio of the current output power of the wind turbine to the wind energy utilization coefficient. The theoretical power is determined according to the relationship between the theoretical input power and the theoretical output power. S1023, when the generator speed is in the second speed region, the target determination curve is selected as the generator speed and power curve, and the theoretical efficiency is obtained by interpolating the current generator speed on the generator speed and power curve. S1024, when the generator speed is in the third speed range or the pitch angle exceeds the preset angle, the target determination curve is selected as the pitch angle versus wind energy utilization coefficient curve and the wind speed versus wind energy curve. The wind energy utilization coefficient is obtained by interpolating the current pitch angle of the wind turbine on the pitch angle versus wind energy utilization coefficient curve. The theoretical input power is determined according to the ratio of the current output power of the wind turbine to the wind energy utilization coefficient. The theoretical power is determined according to the relationship between the theoretical input power and the theoretical output power. The first speed range, the second speed range, and the third speed range increase sequentially.

[0033] The first speed range is the calibration range where the pitch angle is close to 0. The third speed range is a calibration range where the pitch angle is greater than a preset angle, which is the minimum value that keeps the generator speed and power stable.

[0034] Reference Figure 8 and Figure 9 The theoretical power calculated by using the determination method described in the embodiments of this application is close to the actual power of the unit, within ±20kW, which is much higher than the theoretical power calculated by the power curve.

[0035] This application also provides a device for determining the theoretical power of a wind turbine, comprising: The acquisition module is used to obtain the current generator speed and pitch angle of the wind turbine. The theoretical power determination module is used to select a target determination curve that matches the generator speed and the pitch angle from a variety of pre-calibrated theoretical power determination curves, and determine the theoretical power based on the target determination curve; The pre-calibrated curves for determining various theoretical power values ​​are obtained based on historical operating data of the wind turbine.

[0036] Preferably, the theoretical power determination module includes: The first theoretical power determination unit is used to select the target determination curve as the wind speed and power curve when the generator speed is lower than the preset speed N1, and directly obtain the theoretical power by interpolating the current generator wind speed on the wind speed and power curve. The second theoretical power determination unit is used to select the target determination curve as the pitch angle versus wind energy utilization coefficient curve when the generator speed is in the first speed range. The wind energy utilization coefficient is obtained by interpolating the current pitch angle of the wind turbine on the pitch angle versus wind energy utilization coefficient curve. The theoretical input power is determined according to the ratio of the current output power of the wind turbine to the wind energy utilization coefficient. The theoretical power is determined according to the relationship between the theoretical input power and the theoretical output power. The third theoretical power determination unit is used to select the target determination curve as the generator speed and power curve when the generator speed is in the second speed region, and to obtain the theoretical efficiency by interpolating the current generator speed on the generator speed and power curve. The fourth theoretical power determination unit is used to select the target determination curves as the pitch angle versus wind energy utilization coefficient curve and the wind speed versus wind energy curve when the generator speed is in the third speed range or the pitch angle exceeds the preset angle. The wind energy utilization coefficient is obtained by interpolating the current pitch angle of the wind turbine on the pitch angle versus wind energy utilization coefficient curve. The theoretical input power is determined according to the ratio of the current output power of the wind turbine to the wind energy utilization coefficient. The theoretical power is determined according to the relationship between the theoretical input power and the theoretical output power. The second speed range, the third speed range, and the second speed range increase sequentially.

[0037] Furthermore, the term “exemplary” is used herein to mean serving as an example, instance, or illustration. Any aspect or design described herein as “exemplary” is not necessarily to be construed as advantageous compared to other aspects or designs. Rather, the use of the term “exemplary” is intended to present the concept in a concrete manner. As used herein, the term “or” is intended to mean an inclusive “or” rather than an exclusive “or.” That is, unless otherwise specified or clear from the context, “X applies A or B” is intended to mean any of the natural inclusive arrangements. That is, “X applies A or B” satisfies any of the foregoing instances if X applies A; X applies B; or both X applies A and B. Additionally, unless otherwise specified or clear from the context to refer to the singular form, the articles “a” and “an” as used in this application and the appended claims are generally understood to mean “one or more.”

[0038] Similarly, although this disclosure has been shown and described with respect to one or more implementations, equivalent variations and modifications will occur to those skilled in the art upon reading and understanding the specification and drawings. This disclosure includes all such modifications and variations and is limited only by the scope of the claims. In particular, with respect to the various functions performed by the components described above (e.g., elements, resources, etc.), unless otherwise indicated, the terminology used to describe such components is intended to correspond to any component (functionally equivalent) that performs the specific function of the described component, even if structurally not equivalent to the disclosed structure. Furthermore, although specific features of this disclosure may have been disclosed with respect to only one of several implementations, such features may be combined with one or more other features of other implementations, as may be desired and advantageous to any given or particular application. Moreover, with regard to the terms “comprising,” “owning,” “having,” “having,” or variations thereof as used in the detailed description or claims, such terms are intended to be inclusive in a manner similar to the term “including.”

[0039] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the following claims.

[0040] It should be understood that this disclosure is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this disclosure is limited only by the appended claims.

[0041] It should be noted that the terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this disclosure are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this disclosure described herein can be implemented in orders other than those illustrated or described herein. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this disclosure. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this disclosure as detailed in the appended claims.

[0042] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with an embodiment or example is included in at least one embodiment or example of this disclosure. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0043] Any process or method description in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or more executable instructions for implementing a particular logical function or process, and the scope of preferred embodiments of this disclosure includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the function involved, as will be understood by those skilled in the art to which embodiments of this disclosure pertain.

[0044] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a system including a processing module, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (control method), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic device, and portable optical disc read-only memory (CDROM). Furthermore, computer-readable media can even be paper or other suitable media on which programs can be printed, because programs can be obtained electronically, for example, by optically scanning the paper or other media, followed by editing, interpreting, or otherwise processing as necessary, and then stored in computer memory.

[0045] It should be understood that various parts of the embodiments of this disclosure can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0046] Those skilled in the art will understand that all or part of the steps of the methods in the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, the program includes one or a combination of the steps of the method embodiments.

[0047] Furthermore, the functional units in the various embodiments of this disclosure can be integrated into a single processing module, or each unit can exist physically separately, or two or more units can be integrated into a single module. The integrated module can be implemented in hardware or as a software functional module. If the integrated module is implemented as a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium. The aforementioned storage medium can be a read-only memory, a hard disk, or an optical disk, etc.

[0048] Although embodiments of the present disclosure have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present disclosure. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present disclosure.

Claims

1. A method for determining the theoretical power of a wind turbine generator set, characterized in that, include: Obtain the current generator speed and pitch angle of the wind turbine; Based on the generator speed and pitch angle, a target determination curve matching the generator speed and pitch angle is selected from a variety of pre-calibrated theoretical power determination curves, and the theoretical power is determined based on the target determination curve. The pre-calibrated curves for determining various theoretical power values ​​are obtained based on historical operating data of the wind turbine.

2. The method for determining the theoretical power of a wind turbine generator according to claim 1, characterized in that, The step of selecting a target determination curve that matches the generator speed and the pitch angle from a variety of pre-calibrated theoretical power determination curves, based on the generator speed and pitch angle, includes: When the generator speed is lower than the preset speed N1, the target determination curve is selected as the wind speed and power curve, and the theoretical power is directly obtained by interpolating the current generator wind speed on the wind speed and power curve. When the generator speed is in the first speed range, the target determination curve is selected as the pitch angle versus wind energy utilization coefficient curve. The wind energy utilization coefficient is obtained by interpolating the current pitch angle of the wind turbine on the pitch angle versus wind energy utilization coefficient curve. The theoretical input power is determined according to the ratio of the current output power of the wind turbine to the wind energy utilization coefficient. The theoretical power is determined according to the relationship between the theoretical input power and the theoretical output power. When the generator speed is in the second speed region, the target determination curve is selected as the generator speed and power curve, and the theoretical efficiency is obtained by interpolating the current generator speed on the generator speed and power curve. When the generator speed is in the third speed range or the pitch angle exceeds the preset angle, the target determination curves are selected as the pitch angle versus wind energy utilization coefficient curve and the wind speed versus wind energy curve. The wind energy utilization coefficient is obtained by interpolating the current pitch angle of the wind turbine on the pitch angle versus wind energy utilization coefficient curve. The theoretical input power is determined according to the ratio of the current output power of the wind turbine to the wind energy utilization coefficient. The theoretical power is determined according to the relationship between the theoretical input power and the theoretical output power. The first speed range, the second speed range, and the third speed range increase sequentially.

3. The method for determining the theoretical power of a wind turbine generator according to claim 1, characterized in that, The pre-calibrated curves for determining various theoretical power outputs are obtained based on historical operating data of the wind turbine generators. Based on the historical operating data of the wind turbine units after anomaly screening, wind speed and power curves were constructed at intervals of 0.1 m / s; and generator speed and power curves and pitch angle and power curves were constructed at intervals of 50 kW respectively. Based on the pitch angle and power curve, determine the power corresponding to different pitch angles; Based on the power corresponding to different pitch angles, the wind energy utilization coefficient is determined to construct a pitch angle versus wind energy utilization coefficient curve.

4. A device for determining the theoretical power of a wind turbine generator set, characterized in that, include: The acquisition module is used to obtain the current generator speed and pitch angle of the wind turbine. The theoretical power determination module is used to select a target determination curve that matches the generator speed and the pitch angle from a variety of pre-calibrated theoretical power determination curves, and determine the theoretical power based on the target determination curve; The pre-calibrated curves for determining various theoretical power values ​​are obtained based on historical operating data of the wind turbine.

5. The device for determining the theoretical power of a wind turbine generator according to claim 4, characterized in that, The theoretical power determination module includes: The first theoretical power determination unit is used to select the target determination curve as the wind speed and power curve when the generator speed is lower than the preset speed N1, and directly obtain the theoretical power by interpolating the current generator wind speed on the wind speed and power curve. The second theoretical power determination unit is used to select the target determination curves as the pitch angle and wind energy utilization coefficient curve and the wind speed and wind energy curve when the generator speed is in the first speed range. The wind energy is obtained by interpolating the current wind speed on the wind speed and wind energy curve, and the wind energy utilization coefficient is obtained by interpolating the current pitch angle on the pitch angle and wind energy utilization coefficient curve. The theoretical power is obtained by multiplying the wind energy and the wind energy coefficient. The third theoretical power determination unit is used to select the target determination curve as the generator speed and power curve when the generator speed is in the second speed region, and to obtain the theoretical efficiency by interpolating the current generator speed on the generator speed and power curve. The fourth theoretical power determination unit is used to select the target determination curves as the pitch angle and wind energy utilization coefficient curve and the wind speed and wind energy curve when the generator speed is in the third speed region. The wind energy is obtained by interpolating the current wind speed on the wind speed and wind energy curve, and the wind energy utilization coefficient is obtained by interpolating the current pitch angle on the pitch angle and wind energy utilization coefficient curve. The theoretical power is obtained by multiplying the wind energy and the wind energy coefficient. The second speed range, the third speed range, and the second speed range increase sequentially.

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