Evaluation Method, Related Device and Storage Medium for Power Limit of Fan Inertia Support

Abstract

The present application provides a method for evaluating the power limit of the inertia support of a fan, related devices and storage media, which are applied to the technical field of power systems. The fitting coefficient of the mechanical power is determined based on the power coefficient of the fan; then, according to the preset active power output drop constraint, the first rotational speed constraint, the mechanical power input to the fan, and the fitting coefficient of the mechanical power, the target rotational speed constraint and the mechanical power of the fan under the target rotational speed constraint are determined; thereafter, based on the fan rotational speed at the start of the inertia support stage, the mechanical power at the start of the inertia support stage, the target rotational speed constraint, and the mechanical power of the fan under the target rotational speed constraint, the approximate coefficient of the mechanical power is determined; finally, based on the approximate coefficient of the mechanical power, the angular velocity of the wind turbine rotor, the target rotational speed constraint, and the incremental limit of the fan output, the evaluation result of the power limit of the inertia support of the fan is generated. It effectively provides a basis for the optimal power distribution of the wind farm during inertia support and for ensuring the safe operation of the unit.

Description

Technical Field

[0001] This application relates to the technical field of power systems, and particularly to an evaluation method for the power limit of wind turbine inertia support, related devices, and storage media. Background Art

[0002] With the continuous increase of wind power penetration in the power grid, the equivalent inertia of the power grid shows a significant downward trend, which makes the participation of wind farms in power grid inertia support a key technology to ensure the frequency safety of the power grid.

[0003] The existing operation mechanism is that the wind farm supports the power grid frequency recovery by dynamically increasing the active power based on the inertia coefficient and droop coefficient specified by the power grid. However, while this regulation method improves the frequency stability of the power grid, it may cause excessive consumption of the kinetic energy of the wind turbine and rotor, resulting in the safety risk of the wind turbine tripping due to low-speed protection actions. Summary of the Invention

[0004] In view of this, this application provides an evaluation method for the power limit of wind turbine inertia support, related devices, and storage media, which effectively provides a basis for the optimal power distribution of the wind farm during inertia support and ensures the safe operation of the units.

[0005] The first aspect of this application provides an evaluation method for the power limit of wind turbine inertia support, including:

[0006] Obtain the power coefficient of the wind turbine, the mechanical power input to the wind turbine, the wind turbine speed at the start of the inertia support stage, and the mechanical power at the start of the inertia support stage in real time;

[0007] Determine the fitting coefficient of the mechanical power based on the power coefficient of the wind turbine;

[0008] Determine the target speed constraint and the mechanical power of the wind turbine under the target speed constraint according to the preset active power drop constraint, the first speed constraint, the mechanical power input to the wind turbine, and the fitting coefficient of the mechanical power;

[0009] Determine the approximation coefficient of the mechanical power based on the wind turbine speed at the start of the inertia support stage, the mechanical power at the start of the inertia support stage, the target speed constraint, and the mechanical power of the wind turbine under the target speed constraint;

[0010] Generate an evaluation result for the power limit of wind turbine inertia support based on the approximation coefficient of the mechanical power, the angular velocity of the wind turbine rotor, the target speed constraint, and the increment limit of the wind turbine output.

[0011] Optionally, the determining the fitting coefficient of the mechanical power based on the power coefficient of the wind turbine includes:

[0012] Perform fitting on the power coefficient of the wind turbine to obtain the fitting coefficient of the power data of the wind turbine;

[0013] Based on the fitting coefficient of the power data of the fan and the mathematical model of the mechanical power of the fan, the fitting coefficient of the mechanical power is obtained.

[0014] Optionally, the determination of the target speed constraint and the mechanical power of the fan under the target speed constraint according to the preset active power drop constraint, the first speed constraint, the mechanical power input by the fan, and the fitting coefficient of the mechanical power includes:

[0015] Determine the mechanical power constraint of the fan based on the preset active power drop constraint, the mechanical power at the start of the inertia support stage, and the mechanical power input by the fan;

[0016] Determine the second speed constraint based on the mechanical power constraint of the fan, the preset active power drop constraint, the mechanical power at the start of the inertia support stage, and the fitting coefficient of the mechanical power;

[0017] Take the larger value of the first speed constraint and the second speed constraint as the target speed constraint;

[0018] Determine the mechanical power of the fan under the target speed constraint according to the target speed constraint and the fitting coefficient of the mechanical power.

[0019] Optionally, the generation of the fan inertia support power limit evaluation result based on the approximate coefficient of the mechanical power, the wind turbine angular velocity, the target speed constraint, and the increment limit of the fan output includes:

[0020] Determine the approximate value of the mechanical power according to the approximate coefficient of the mechanical power and the wind turbine angular velocity;

[0021] Determine the duration of the inertia support stage according to the approximate value of the mechanical power and the fan rotor motion equation based on a single mass block;

[0022] Determine the corresponding relationship between the target speed constraint and the inertia support power limit according to the equivalent rotational inertia of the fan on the wind turbine side, the duration of the inertia support stage, the approximate coefficient of the mechanical power, the inertia support power output by the fan, the target speed constraint, and the mechanical power at the start of the inertia support stage;

[0023] Generate the fan inertia support power limit evaluation result based on the corresponding relationship between the target speed constraint and the inertia support power limit, the mechanical power at the start of the inertia support stage, and the increment limit of the fan output.

[0024] Optionally, after generating the fan inertia support power limit evaluation result based on the approximate coefficient of the mechanical power, the wind turbine angular velocity, the target speed constraint, and the increment limit of the fan output, it further includes:

[0025] Determine the optimal power distribution plan of the wind farm during the inertia support based on the power limit of the fan inertia support.

[0026] Optionally, after generating the evaluation result of the fan inertia support power limit based on the approximate coefficient of the mechanical power, the angular velocity of the wind turbine, the target speed constraint, and the increment limit of the fan output, it further includes:

[0027] Report the evaluation result of the fan inertia support power limit.

[0028] Optionally, the evaluation method of the fan inertia support power limit further includes:

[0029] Determine the electromagnetic power output by the fan during the speed recovery stage according to the approximate value of the fan mechanical power at the end of the inertia support stage, the approximate coefficient of the mechanical power, the fan speed at the end of the inertia support stage, the duration of the inertia support stage, the equivalent rotational inertia of the fan on the wind turbine side, the inertia support power output by the fan, and the fan speed at the start of the inertia support stage.

[0030] The second aspect of this application provides an evaluation device for the fan inertia support power limit, including:

[0031] An acquisition unit for real-time acquisition of the power coefficient of the fan, the mechanical power input to the fan, the fan speed at the start of the inertia support stage, and the mechanical power at the start of the inertia support stage;

[0032] A first determination unit for determining the fitting coefficient of the mechanical power based on the power coefficient of the fan;

[0033] A second determination unit for determining the target speed constraint and the mechanical power of the fan under the target speed constraint according to the preset active power drop constraint, the first speed constraint, the mechanical power input to the fan, and the fitting coefficient of the mechanical power;

[0034] A third determination unit for determining the approximate coefficient of the mechanical power based on the fan speed at the start of the inertia support stage, the mechanical power at the start of the inertia support stage, the target speed constraint, and the mechanical power of the fan under the target speed constraint;

[0035] A generation unit for generating an evaluation result of the fan inertia support power limit based on the approximate coefficient of the mechanical power, the angular velocity of the wind turbine, the target speed constraint, and the increment limit of the fan output.

[0036] Optionally, the first determination unit includes:

[0037] A fitting unit for fitting the power coefficient of the fan to obtain the fitting coefficient of the power data of the fan;

[0038] A first determination subunit, configured to obtain a fitting coefficient of mechanical power based on a fitting coefficient of power data of a wind turbine and a mathematical model of the mechanical power of the wind turbine.

[0039] Optionally, the second determination unit includes:

[0040] A wind turbine mechanical power constraint determination unit, configured to determine a wind turbine mechanical power constraint based on a preset active power output drop constraint, the mechanical power at the start of the inertia support stage, and the mechanical power input to the wind turbine;

[0041] A second rotational speed constraint determination unit, configured to determine a second rotational speed constraint based on the wind turbine mechanical power constraint, the preset active power output drop constraint, the mechanical power at the start of the inertia support stage, and the fitting coefficient of the mechanical power;

[0042] A target rotational speed constraint determination unit, configured to use the larger value between the first rotational speed constraint and the second rotational speed constraint as the target rotational speed constraint;

[0043] A mechanical power determination unit under the target rotational speed constraint, configured to determine the mechanical power of the wind turbine under the target rotational speed constraint according to the target rotational speed constraint and the fitting coefficient of the mechanical power.

[0044] Optionally, the generating unit includes:

[0045] An approximation value determination unit, configured to determine an approximation value of the mechanical power according to the approximation coefficient of the mechanical power and the angular velocity of the wind wheel;

[0046] A duration determination unit of the inertia support stage, configured to determine the duration of the inertia support stage according to the approximation value of the mechanical power and the wind turbine rotor motion equation based on a single mass block;

[0047] A correspondence determination unit, configured to determine the correspondence between the target rotational speed constraint and the inertia support power limit according to the equivalent rotational inertia of the wind turbine on the wind wheel side, the duration of the inertia support stage, the approximation coefficient of the mechanical power, the inertia support power output by the wind turbine, the target rotational speed constraint, and the mechanical power at the start of the inertia support stage;

[0048] A generating subunit, configured to generate an evaluation result of the inertia support power limit of the wind turbine based on the correspondence between the target rotational speed constraint and the inertia support power limit, the mechanical power at the start of the inertia support stage, and the increment limit of the wind turbine output.

[0049] Optionally, the evaluation device for the inertia support power limit of the wind turbine further includes:

[0050] An optimal allocation scheme determination unit, configured to determine an optimal power allocation scheme of the wind farm during the inertia support period based on the inertia support power limit of the wind turbine.

[0051] Optionally, the evaluation device for the power limit of the fan inertia support further includes:

[0052] A reporting unit for reporting the evaluation result of the power limit of the fan inertia support.

[0053] Optionally, the evaluation device for the power limit of the fan inertia support further includes:

[0054] An electromagnetic power determination unit for determining the electromagnetic power output by the fan during the speed recovery stage according to the approximation of the mechanical power of the fan at the end moment of the inertia support stage, the approximation coefficient of the mechanical power, the fan speed at the end moment of the inertia support stage, the duration of the inertia support stage, the equivalent rotational inertia of the fan on the wind turbine side, the inertia support power output by the fan, and the fan speed at the start moment of the inertia support stage.

[0055] A third aspect of the present application provides an electronic device, including:

[0056] One or more processors;

[0057] A storage device having one or more programs stored thereon;

[0058] When the one or more programs are executed by the one or more processors, the one or more processors are caused to implement the evaluation method for the power limit of the fan inertia support as described in any one of the first aspects.

[0059] A fourth aspect of the present application provides a storage medium having a computer program stored thereon, wherein the computer program implements the evaluation method for the power limit of the fan inertia support as described in any one of the first aspects when executed by a processor.

[0060] As can be seen from the above solutions, the present application provides an evaluation method, related device, and storage medium for the power limit of the fan inertia support. By determining the fitting coefficient of the mechanical power based on the power coefficient of the fan; then, determining the target speed constraint and the mechanical power of the fan under the target speed constraint according to the preset active power drop constraint, the first speed constraint, the mechanical power input by the fan, and the fitting coefficient of the mechanical power; then, determining the approximation coefficient of the mechanical power based on the fan speed at the start moment of the inertia support stage, the mechanical power at the start of the inertia support stage, the target speed constraint, and the mechanical power of the fan under the target speed constraint; finally, generating an evaluation result for the power limit of the fan inertia support based on the approximation coefficient of the mechanical power, the angular velocity of the wind turbine, the target speed constraint, and the increment limit of the fan output. It effectively provides a basis for the optimal power distribution of the wind farm during inertia support and ensuring the safe operation of the unit. Description of the Drawings

[0061] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings described below are only the embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on the provided drawings.

[0062] Figure 1 It is a specific flowchart of a method for evaluating the power limit of a fan inertia support provided by an embodiment of the present application;

[0063] Figure 2 It is a flowchart of a method for determining the target speed constraint and the mechanical power of a fan under the target speed constraint provided by another embodiment of the present application;

[0064] Figure 3 It is a flowchart of a method for generating an evaluation result of the power limit of a fan inertia support provided by another embodiment of the present application;

[0065] Figure 4 It is a schematic diagram of the comparison between the fitted value and the approximate value of the mechanical power provided by another embodiment of the present application;

[0066] Figure 5 It is a schematic diagram of an evaluation device for the power limit of a fan inertia support provided by another embodiment of the present application;

[0067] Figure 6 It is a schematic diagram of an electronic device for implementing a method for evaluating the power limit of a fan inertia support provided by another embodiment of the present application. Specific Embodiments

[0068] The following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of them. Based on the embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope protected by the present application.

[0069] The term "comprising" and its variants used herein are open-ended, that is, "including but not limited to". The term "based on" is "at least partially based on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments". The relevant definitions of other terms will be given in the following description.

[0070] It should be noted that the information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties.

[0071] It should be noted that the concepts such as "first", "second", etc. mentioned in this application are only used to distinguish different devices, modules or units, and are not used to limit the order or interdependent relationship of the functions performed by these devices, modules or units.

[0072] It should be noted that the modifications of "one" and "multiple" mentioned in this application are illustrative rather than restrictive. Those skilled in the art should understand that unless otherwise clearly specified in the context, it should be understood as "one or more".

[0073] The embodiment of this application provides an evaluation method for the power limit of the fan inertia support, as Figure 1 shown, which specifically includes the following steps:

[0074] S101. Real-time obtain the power coefficient of the fan, the mechanical power input to the fan, the fan speed at the start moment of the inertia support stage, and the mechanical power at the start of the inertia support stage.

[0075] In the specific implementation process of this application, it is possible but not limited to directly and real-time obtain the power coefficient of the fan, the mechanical power input to the fan, the fan speed at the start moment of the inertia support stage, and the mechanical power at the start of the inertia support stage in the control system, and no limitation is made here.

[0076] S102. Determine the fitting coefficient of the mechanical power based on the power coefficient of the fan.

[0077] Optionally, in another embodiment of this application, an implementation manner of step S102 specifically includes the following steps:

[0078] Perform fitting on the power coefficient of the fan to obtain the fitting coefficient of the power data of the fan; based on the fitting coefficient of the power data of the fan and the mathematical model of the mechanical power of the fan, obtain the fitting coefficient of the mechanical power.

[0079] First of all, it should be noted that the fan rotor motion equation based on a single mass block is:

[0080] (1)

[0081] In formula (1), represents the equivalent rotational inertia of the fan on the wind turbine side, represents the angular velocity of the wind turbine, and respectively represent the mechanical torque and electromagnetic torque of the fan, and respectively represent the mechanical power input to the fan and the electromagnetic power output, t represents time, and d is the differential symbol.

[0082] Among them, the mathematical model of mechanical power is:

[0083] (2)

[0084] In Equation (2), represents the air density, represents the power coefficient of the fan, represents the blade radius, represents the wind speed, represents the tip speed ratio, represents the pitch angle of the fan. The empirical formula of

[0085] (3)

[0086] In Equation (3), , and are all fitting coefficients of the power coefficient. It should be noted that Equation (3) mainly describes the quantitative relationship between the power coefficient and the tip speed ratio when the pitch angle is fixed. When the pitch angle changes, the fitting coefficients will also change accordingly.

[0087] Among them, the fan manufacturer will give the corresponding values of the power coefficient at different tip speed ratios and pitch angles in tabular form. Based on these data, quadratic fitting as shown in Equation (3) is performed to obtain the three coefficients , and of the quadratic function.

[0088] In the specific implementation process of the present invention, after substituting Equation (3) into Equation (2), the mechanical power of the fan can also be transformed into the form of a quadratic function related to the fan speed:

[0089] (4)

[0090] In Equation (4), , and are respectively the fitting coefficients of the mechanical power.

[0091] S103. Determine the target speed constraint and the mechanical power of the fan under the target speed constraint according to the preset active power output drop constraint, the first speed constraint, the mechanical power input by the fan, and the fitting coefficient of the mechanical power.

[0092] Among them, the preset active power output drop constraint is set according to the specified active power drop constraint, and the first speed constraint is set according to the lower limit of the motor speed safety given by the manufacturer, which is not limited here.

[0093] Optionally, in another embodiment of the present application, an implementation manner of step S103 is as Figure 2 shown, including:

[0094] S201. Determine the mechanical power constraint of the fan based on the preset active power output drop constraint, the mechanical power at the start of the inertia support stage, and the mechanical power input by the fan.

[0095] In the specific implementation process of the present application, the following formula can be used to determine the mechanical power constraint of the fan:

[0096] (5)

[0097] Among them, is the preset active power output drop constraint, is the mechanical power at the start of the inertia support stage, represents the mechanical power input by the fan.

[0098] S202. Determine the second speed constraint based on the mechanical power constraint of the fan, the preset active power output drop constraint, the mechanical power at the start of the inertia support stage, and the fitting coefficient of the mechanical power.

[0099] Continuing with the above example, according to formulas (4) and (5), the fan speed constraint corresponding to the active power output drop constraint can be solved, that is, the second speed constraint is:

[0100] (6)

[0101] S203. Take the larger value of the first speed constraint and the second speed constraint as the target speed constraint.

[0102] Among them, the target speed constraint is the speed constraint including the active power output drop constraint.

[0103] Specifically, take the larger value of the first speed constraint and the second speed constraint as the target speed constraint .

[0104] S204. Determine the mechanical power of the fan under the target speed constraint according to the fitting coefficient of the target speed constraint and the mechanical power.

[0105] Continuing the above example, the corresponding fan mechanical power can be solved according to Equation (4). The corresponding mechanical power of the fan , that is, the mechanical power of the fan under the target speed constraint.

[0106] S104. Determine the approximate coefficient of the mechanical power based on the fan speed at the start of the inertia support stage, the mechanical power at the start of the inertia support stage, the target speed constraint, and the mechanical power of the fan under the target speed constraint.

[0107] In the specific implementation process of this application, the following formula can be used to determine the approximate coefficient of the mechanical power:

[0108] (7)

[0109] In Equation (7), represents the fan speed at the start of the inertia support stage, and are both approximate coefficients of the mechanical power.

[0110] S105. Generate an evaluation result of the fan inertia support power limit based on the approximate coefficient of the mechanical power, the angular velocity of the wind turbine rotor, the target speed constraint, and the increment limit of the fan output.

[0111] Among them, the increment limit of the fan output is generally set to 12% of the rated power of the fan, which is not limited here.

[0112] Optionally, in another embodiment of this application, an implementation manner of step S105, as Figure 3 shown, includes:

[0113] S301. Determine the approximate value of the mechanical power according to the approximate coefficient of the mechanical power and the angular velocity of the wind turbine rotor.

[0114] Continuing the above example, substituting Equation (4) into Equation (1) can obtain the complete differential equation of the wind turbine rotor speed during the inertia support period:

[0115] (8)

[0116] In the formula, represents the inertia support power output by the fan. The general solution of Equation (8) is:

[0117] (9)

[0118] In Equation (9), represents the duration of the inertia support stage, and represent the mechanical power of the wind turbine at the start and end moments of the inertia support stage respectively, and represent the rotational speed of the wind turbine at the start and end moments of the inertia support stage respectively.

[0119] However, Equation (9) is still too complex to obtain an explicit expression for the rotational speed, and it is thus difficult to analyze the influence mechanism of various constraints on the inertia support power limit. In order to obtain an explicit expression for the rotational speed, the present invention further proposes a scaling method for mechanical power, and the approximate value of the mechanical power is:

[0120] (10)

[0121] Figure 4 shows the comparison between the fitted value and the approximate value of the mechanical power. It can be found that the approximate value of the mechanical power is always less than the fitted value within the set rotational speed range, that is . The main purposes of this scaling are: one is to facilitate obtaining an explicit expression for the rotational speed, and the other is to reserve part of the mechanical power as standby power to further reduce the probability of the event that the rotational speed of the wind turbine drops rapidly due to the wind speed drop during the inertia support period.

[0122] S302. Determine the duration of the inertia support stage according to the approximate value of the mechanical power and the wind turbine rotor motion equation based on a single mass block.

[0123] Specifically, substituting Equation (10) into Equation (1) can re-obtain the complete differential equation of the wind turbine rotational speed during the inertia support period:

[0124] (11)

[0125] The general solution of the above is:

[0126] (12)

[0127] In the formula, represents squared, represents squared.

[0128] S303. Determine the corresponding relationship between the target rotational speed constraint and the inertia support power limit according to the equivalent rotational inertia of the wind turbine on the rotor side, the duration of the inertia support stage, the approximate coefficient of the mechanical power, the inertia support power output by the wind turbine, the target rotational speed constraint, and the mechanical power at the start of the inertia support stage.

[0129] Continuing with the above example, Equation (12) can be further transformed into:

[0130] (13)

[0131] Then the corresponding relationship between the target speed constraint and the inertia support power limit can be obtained:

[0132] (14)

[0133] S304. Generate the evaluation result of the fan inertia support power limit based on the corresponding relationship between the target speed constraint and the inertia support power limit, the mechanical power at the start of the inertia support stage, and the increment limit of the fan output.

[0134] Continuing with the above example, calculate the corresponding fan inertia support power limit according to Equation (14), and at the same time consider the increment limit of the fan output , to obtain the fan inertia support power limit under multiple constraints:

[0135] (15)

[0136] Specifically, generate the evaluation result of the fan inertia support power limit based on the fan inertia support power limit.

[0137] It should be noted that the electromagnetic power output by the fan during the speed recovery stage needs to be lower than the mechanical power input to the fan to achieve the speed recovery of the fan. Therefore, the upper limit of the electromagnetic power output by the fan during the speed recovery stage is the mechanical power input to the fan at the moment of the lowest speed.

[0138] To effectively suppress the active power drop of the fan during the speed recovery stage, the evaluation result of the fan inertia support power limit also includes the electromagnetic power output by the fan during the speed recovery stage. The electromagnetic power output by the fan during the speed recovery stage is its upper limit value. For this reason, an implementation manner of the evaluation method of the fan inertia support power limit in the present invention further includes:

[0139] Determine the electromagnetic power output by the fan during the speed recovery stage according to the approximate value of the fan mechanical power at the end of the inertia support stage, the approximate coefficient of the mechanical power, the fan speed at the end of the inertia support stage, the duration of the inertia support stage, the equivalent rotational inertia of the fan on the wind turbine side, the inertia support power output by the fan, and the fan speed at the start of the inertia support stage.

[0140] In the specific implementation process of the present application, the following calculation formula can be used to calculate the electromagnetic power output by the fan during the speed recovery stage :

[0141] (16)

[0142] Wherein, It represents an approximation of the mechanical power of the wind turbine at the termination moment of the inertia support stage.

[0143] In the specific implementation process of this application, after obtaining the evaluation result of the inertia support power limit of the wind turbine, a power optimization distribution plan for the wind farm during the inertia support period can be further determined based on the inertia support power limit of the wind turbine to ensure the safe operation of the unit.

[0144] In the specific implementation process of this application, after obtaining the evaluation result of the inertia support power limit of the wind turbine, the evaluation result of the inertia support power limit of the wind turbine can be further reported to evaluate the overall frequency stability of the system.

[0145] As can be seen from the above solutions, this application provides a method for evaluating the inertia support power limit of a wind turbine. By determining the fitting coefficient of the mechanical power based on the power coefficient of the wind turbine; then, according to the preset active power drop constraint, the first rotational speed constraint, the mechanical power input to the wind turbine, and the fitting coefficient of the mechanical power, the target rotational speed constraint and the mechanical power of the wind turbine under the target rotational speed constraint are determined; after that, based on the rotational speed of the wind turbine at the start of the inertia support stage, the mechanical power at the start of the inertia support stage, the target rotational speed constraint, and the mechanical power of the wind turbine under the target rotational speed constraint, the approximate coefficient of the mechanical power is determined; finally, based on the approximate coefficient of the mechanical power, the angular velocity of the wind wheel, the target rotational speed constraint, and the increment limit of the wind turbine output, the evaluation result of the inertia support power limit of the wind turbine is generated. It effectively provides a basis for the power optimization distribution of the wind farm during the inertia support period and ensuring the safe operation of the unit.

[0146] Another embodiment of this application provides an evaluation device for the inertia support power limit of a wind turbine, as Figure 5 shown, specifically including:

[0147] An acquisition unit 501, configured to acquire in real time the power coefficient of the wind turbine, the mechanical power input to the wind turbine, the rotational speed of the wind turbine at the start of the inertia support stage, and the mechanical power at the start of the inertia support stage.

[0148] A first determination unit 502, configured to determine the fitting coefficient of the mechanical power based on the power coefficient of the wind turbine.

[0149] Optionally, in another embodiment of this application, an implementation manner of the first determination unit 502 includes:

[0150] A fitting unit, configured to fit the power coefficient of the wind turbine to obtain the fitting coefficient of the power data of the wind turbine.

[0151] A first determination subunit, configured to obtain the fitting coefficient of the mechanical power based on the fitting coefficient of the power data of the wind turbine and the mathematical model of the mechanical power of the wind turbine.

[0152] For the specific working process of the unit disclosed in the above embodiments of the present application, reference may be made to the corresponding method embodiment content, which will not be elaborated here.

[0153] The second determination unit 503 is configured to determine a target speed constraint and the mechanical power of the fan under the target speed constraint according to a preset active power output drop constraint, a first speed constraint, the mechanical power input by the fan, and the fitting coefficient of the mechanical power.

[0154] Optionally, in another embodiment of the present application, an implementation manner of the second determination unit 503 includes:

[0155] The fan mechanical power constraint determination unit is configured to determine a fan mechanical power constraint based on a preset active power output drop constraint, the mechanical power at the start of the inertia support stage, and the mechanical power input by the fan.

[0156] The second speed constraint determination unit is configured to determine a second speed constraint based on the fan mechanical power constraint, a preset active power output drop constraint, the mechanical power at the start of the inertia support stage, and the fitting coefficient of the mechanical power.

[0157] The target speed constraint determination unit is configured to use the larger value between the first speed constraint and the second speed constraint as the target speed constraint.

[0158] The mechanical power determination unit under the target speed constraint is configured to determine the mechanical power of the fan under the target speed constraint according to the target speed constraint and the fitting coefficient of the mechanical power.

[0159] For the specific working process of the unit disclosed in the above embodiments of the present application, reference may be made to the corresponding method embodiment content, as Figure 2 shown, which will not be elaborated here.

[0160] The third determination unit 504 is configured to determine an approximation coefficient of the mechanical power based on the fan speed at the start of the inertia support stage, the mechanical power at the start of the inertia support stage, the target speed constraint, and the mechanical power of the fan under the target speed constraint.

[0161] The generation unit 505 is configured to generate a fan inertia support power limit evaluation result based on the approximation coefficient of the mechanical power, the wind turbine angular velocity, the target speed constraint, and the increment limit of the fan output.

[0162] For the specific working process of the unit disclosed in the above embodiments of the present application, reference may be made to the corresponding method embodiment content, as Figure 1 shown, which will not be elaborated here.

[0163] Optionally, in another embodiment of the present application, an implementation manner of the generation unit 505 includes:

[0164] An approximation value determination unit for determining an approximation value of mechanical power according to an approximation coefficient of mechanical power and a wind turbine angular velocity.

[0165] A duration determination unit for the inertia support stage, configured to determine the duration of the inertia support stage according to the approximation value of mechanical power and the wind turbine rotor motion equation based on a single mass block.

[0166] A correspondence determination unit for determining the correspondence between the target speed constraint and the inertia support power limit according to the equivalent rotational inertia of the wind turbine on the wind turbine side, the duration of the inertia support stage, the approximation coefficient of mechanical power, the inertia support power output by the wind turbine, the target speed constraint, and the mechanical power at the start of the inertia support stage.

[0167] A generation subunit for generating an evaluation result of the wind turbine inertia support power limit based on the correspondence between the target speed constraint and the inertia support power limit, the mechanical power at the start of the inertia support stage, and the increment limit of the wind turbine output.

[0168] For the specific working process of the units disclosed in the above embodiments of the present application, reference may be made to the corresponding method embodiment content, as Figure 3 shown, and details are not described herein again.

[0169] Optionally, in another embodiment of the present application, an implementation manner of the evaluation device for the wind turbine inertia support power limit further includes:

[0170] An optimization allocation scheme determination unit for determining an optimized power allocation scheme for the wind farm during the inertia support period based on the wind turbine inertia support power limit.

[0171] For the specific working process of the units disclosed in the above embodiments of the present application, reference may be made to the corresponding method embodiment content, and details are not described herein again.

[0172] Optionally, in another embodiment of the present application, an implementation manner of the evaluation device for the wind turbine inertia support power limit further includes:

[0173] A reporting unit for reporting the evaluation result of the wind turbine inertia support power limit.

[0174] For the specific working process of the units disclosed in the above embodiments of the present application, reference may be made to the corresponding method embodiment content, and details are not described herein again.

[0175] Optionally, in another embodiment of the present application, an implementation manner of the evaluation device for the wind turbine inertia support power limit further includes:

[0176] An electromagnetic power determination unit is configured to determine the electromagnetic power output by the fan during the rotational speed recovery phase based on the approximation of the mechanical power of the fan at the termination moment of the inertia support phase, the approximation coefficient of the mechanical power, the rotational speed of the fan at the termination moment of the inertia support phase, the duration of the inertia support phase, the equivalent rotational inertia of the fan on the wind turbine side, the inertia support power output by the fan, and the rotational speed of the fan at the start moment of the inertia support phase.

[0177] For the specific working process of the unit disclosed in the above embodiments of the present application, reference may be made to the corresponding method embodiment content, which will not be elaborated herein.

[0178] As can be seen from the above solutions, the present application provides an evaluation device for the inertia support power limit of a fan. By determining the fitting coefficient of the mechanical power based on the power coefficient of the fan; then, determining the target rotational speed constraint and the mechanical power of the fan under the target rotational speed constraint according to the preset active power output drop constraint, the first rotational speed constraint, the mechanical power input to the fan, and the fitting coefficient of the mechanical power; then, based on the rotational speed of the fan at the start moment of the inertia support phase, the mechanical power at the start of the inertia support phase, the target rotational speed constraint, and the mechanical power of the fan under the target rotational speed constraint, determining the approximation coefficient of the mechanical power; finally, generating an evaluation result of the inertia support power limit of the fan based on the approximation coefficient of the mechanical power, the angular velocity of the wind turbine, the target rotational speed constraint, and the increment limit of the fan output. It effectively provides a basis for the optimal power distribution of the wind farm during inertia support and ensuring the safe operation of the unit.

[0179] The functions described above in this article can be at least partially performed by one or more hardware logic components. For example, without limitation, the exemplary types of hardware logic components that can be used include: Field Programmable Gate Array (FPGA), Application Specific Integrated Circuit (ASIC), Application Specific Standard Product (ASSP), System on Chip (SOC), Complex Programmable Logic Device (CPLD), and so on.

[0180] Another embodiment of the present application provides an electronic device, as Figure 6 shown, including:

[0181] One or more processors 601.

[0182] A storage device 602, on which one or more programs are stored.

[0183] When the one or more programs are executed by the one or more processors 601, the one or more processors 601 are caused to implement the method for evaluating the inertia support power limit of the fan as described in the above embodiments.

[0184] Another embodiment of the present application provides a storage medium, on which a computer program is stored. When the computer program is executed by a processor, it implements the method for evaluating the power limit of the fan inertia support as described in the above embodiments.

[0185] In the context of the present application, a machine-readable medium may be a tangible medium that can contain or store a program for use by or in connection with an instruction execution system, apparatus, or device. A machine-readable medium may be a machine-readable signal medium or a machine-readable storage medium. A machine-readable medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination of the foregoing. More specific examples of a machine-readable storage medium would include an electrical connection based on one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0186] It should be noted that the computer-readable medium in the present application may be a computer-readable signal medium, a computer-readable storage medium, or any combination of the two. The computer-readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination of the above. More specific examples of the computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In the present application, the computer-readable storage medium may be any tangible medium that contains or stores a program that can be used by or in connection with an instruction execution system, apparatus, or device. In the present application, the computer-readable signal medium may include a data signal propagated in a baseband or as part of a carrier wave, which carries computer-readable program code. Such a propagated data signal may take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. The computer-readable signal medium may also be any computer-readable medium other than the computer-readable storage medium, which can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device. The program code contained on the computer-readable medium may be transmitted by any suitable medium, including but not limited to: wires, optical cables, RF (radio frequency), etc., or any suitable combination of the above.

[0187] The above computer-readable medium may be included in the above electronic device; or it may exist separately and not be assembled into the electronic device.

[0188] Another embodiment of the present application provides a computer program product, which is used to execute the above method for evaluating the power limit of the fan inertia support when the computer program product is executed.

[0189] Specifically, according to the embodiments of the present application, the process described above with reference to the flowchart can be implemented as a computer software program. For example, an embodiment of the present application includes a computer program product, which includes a computer program carried on a non-transitory computer-readable medium, and the computer program includes program codes for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from the network through a communication device, or installed from a storage device, or installed from a ROM. When the computer program is executed by a processing device, the above functions defined in the method of the embodiments of the present application are executed.

[0190] Although the subject matter has been described in language specific to structural features and / or methodological logical acts, it should be understood that the subject matter defined in this application is not necessarily limited to the specific features or acts described above. On the contrary, the specific features and acts described above are only example forms of implementing this application.

[0191] Although several specific implementation details are included in the above discussion, these should not be construed as limitations on the scope of this application. Certain features described in the context of separate embodiments can also be implemented in combination in a single embodiment. On the contrary, the various features described in the context of a single embodiment can also be implemented separately or in any suitable sub-combination in multiple embodiments.

[0192] The above description is only a preferred embodiment of this application and an explanation of the applied technical principles. Those skilled in the art should understand that the scope of the application involved in this application is not limited to the technical solutions formed by the specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the above application concept. For example, the technical solutions formed by mutually replacing the above features with (but not limited to) technical features with similar functions applied in this application.

Claims

1. A method for evaluating the inertia support power limit of a wind turbine, characterized in that: include: Obtain in real time the fan power coefficient, the fan input mechanical power, the fan speed at the start of the inertia support phase, and the mechanical power at the start of the inertia support phase; Fitting the power coefficient of the fan to obtain the fitting coefficient of the power data of the fan; Based on the fitting coefficient of the power data of the fan and the mathematical model of the mechanical power of the fan, the fitting coefficient of the mechanical power is obtained; Determine the mechanical power constraint of the wind turbine based on the preset active power drop constraint, the mechanical power at the start of the inertia support phase, and the mechanical power input to the wind turbine; Determine the second speed constraint based on the wind turbine mechanical power constraint, the preset active power output drop constraint, the mechanical power at the start of the inertia support phase, and the fitting coefficient of the mechanical power; The larger value of the first speed constraint and the second speed constraint is used as the target speed constraint; wherein the first speed constraint is set according to the motor speed safety lower limit provided by the manufacturer; Determining the mechanical power of the fan under the target speed constraint according to the target speed constraint and the fitting coefficient of the mechanical power; Determine the approximate mechanical power coefficient based on the fan speed at the start of the inertia support phase, the mechanical power at the start of the inertia support phase, the target speed constraint, and the mechanical power of the fan under the target speed constraint. Generate the wind turbine inertia support power limit assessment result based on the approximate mechanical power coefficient, rotor angular velocity, target speed constraint, and incremental limit of wind turbine output; The power coefficient of the wind turbine is fitted to obtain the fitting coefficient of the power data of the wind turbine, including: ； Where, represents the power coefficient of the fan, represents the blade radius, represents wind speed, represents the tip speed ratio, represents the angular velocity of the wind wheel, 、 and All are fitting coefficients of power data; The fitting coefficient of the mechanical power is obtained based on the fitting coefficient of the power data of the wind turbine and the mathematical model of the mechanical power of the wind turbine, including: The mathematical model of mechanical power is: ； Where, represents the air density, represents the power coefficient of the fan, represents the blade radius, represents wind speed, represents the tip speed ratio, represents the pitch angle of the wind turbine, represents the angular velocity of the wind wheel; Represents the mechanical power input by the fan; The power coefficient of the above fan Substituting the corresponding formula into the mathematical model of mechanical power yields the quadratic function of the fan speed: ； Where, 、 and are the fitting coefficients of mechanical power respectively; The second speed constraint is determined based on the wind turbine mechanical power constraint, the preset active power output drop constraint, the mechanical power at the start of the inertia support phase, and the fitting coefficient of the mechanical power, including: Wind turbine mechanical power constraints: ； Where, For the preset active power output drop constraint, is the mechanical power at the beginning of the inertia support stage, Represents the mechanical power input by the fan; According to the mechanical power constraint of the fan and the quadratic function of the fan speed, the fan speed constraint corresponding to the active output drop constraint is solved, that is, the second speed constraint for: ； The approximate coefficient of mechanical power is determined based on the fan speed at the start of the inertia support phase, the mechanical power at the start of the inertia support phase, the target speed constraint, and the mechanical power of the fan under the target speed constraint, including: ； Where, Indicates the fan speed at the start of the inertia support phase, and are approximate coefficients of mechanical power, The target speed constraint can be solved according to the quadratic function of the fan speed. Corresponding fan mechanical power , that is, the mechanical power of the fan under the target speed constraint.

2. The method for evaluating the wind turbine inertia support power limit according to claim 1, characterized in that: The method generates a wind turbine inertia support power limit assessment result based on the approximate coefficient of mechanical power, the rotor angular velocity, the target speed constraint, and the incremental limit of the wind turbine output, including: Determining an approximate value of mechanical power according to the approximate coefficient of mechanical power and the angular velocity of the wind wheel; Determine the duration of the inertia support phase based on an approximate value of the mechanical power and the equation of motion of the wind turbine rotor based on a single mass block; Determine the corresponding relationship between the target speed constraint and the inertia support power limit based on the equivalent rotational inertia of the wind turbine on the rotor side, the duration of the inertia support phase, the approximate coefficient of mechanical power, the inertia support power output by the wind turbine, the target speed constraint, and the mechanical power at the start of the inertia support phase; Based on the correspondence between the target speed constraint and the inertia support power limit, the mechanical power at the start of the inertia support phase, and the incremental limit of the wind turbine output, the wind turbine inertia support power limit evaluation result is generated.

3. The method for evaluating the wind turbine inertia support power limit according to claim 1, characterized in that: After generating the wind turbine inertia support power limit assessment result based on the approximate coefficient of mechanical power, the rotor angular velocity, the target speed constraint, and the incremental limit of the wind turbine output, the method further includes: The optimal power allocation scheme of the wind farm during inertia support period is determined based on the wind turbine inertia support power limit.

4. The method for evaluating the wind turbine inertia support power limit according to claim 1, characterized in that: After generating the wind turbine inertia support power limit assessment result based on the approximate coefficient of mechanical power, the rotor angular velocity, the target speed constraint, and the incremental limit of the wind turbine output, the method further includes: Report the assessment results of the wind turbine inertia support power limit.

5. The method for evaluating the wind turbine inertia support power limit according to claim 1, characterized in that: Also includes: The electromagnetic power output by the fan during the speed recovery phase is determined based on the approximate value of the fan mechanical power at the end of the inertia support phase, the approximate coefficient of the mechanical power, the fan speed at the end of the inertia support phase, the duration of the inertia support phase, the equivalent rotational inertia of the fan on the rotor side, the inertia support power output by the fan, and the fan speed at the start of the inertia support phase.

6. A device for evaluating the inertia support power limit of a wind turbine, characterized in that: include: An acquisition unit is used to acquire in real time the power coefficient of the fan, the mechanical power input to the fan, the fan speed at the start of the inertia support phase, and the mechanical power at the start of the inertia support phase; A fitting unit, used for fitting the power coefficient of the fan to obtain a fitting coefficient of the power data of the fan; A first determining subunit is configured to obtain a fitting coefficient of mechanical power based on the fitting coefficient of the power data of the wind turbine and a mathematical model of the mechanical power of the wind turbine; a wind turbine mechanical power constraint determination unit, configured to determine the wind turbine mechanical power constraint based on a preset active power output drop constraint, the mechanical power at the start of the inertia support phase, and the mechanical power input to the wind turbine; a target speed constraint determining unit, configured to use the larger value of the first speed constraint and the second speed constraint as the target speed constraint; wherein the first speed constraint is set according to the motor speed safety lower limit provided by the manufacturer; a mechanical power determination unit under target speed constraint, configured to determine the mechanical power of the wind turbine under target speed constraint according to the target speed constraint and a fitting coefficient of the mechanical power; a third determining unit, configured to determine an approximate coefficient of mechanical power based on the fan speed at the start of the inertia support phase, the mechanical power at the start of the inertia support phase, the target speed constraint, and the mechanical power of the fan under the target speed constraint; A generating unit, configured to generate a wind turbine inertia support power limit assessment result based on an approximate coefficient of mechanical power, a wind rotor angular velocity, a target speed constraint, and an incremental limit of wind turbine output; The power coefficient of the wind turbine is fitted to obtain the fitting coefficient of the power data of the wind turbine, including: ； Where, represents the power coefficient of the fan, represents the blade radius, represents wind speed, represents the tip speed ratio, represents the angular velocity of the wind wheel, 、 and All are fitting coefficients of power data; The fitting coefficient of the mechanical power is obtained based on the fitting coefficient of the power data of the wind turbine and the mathematical model of the mechanical power of the wind turbine, including: The mathematical model of mechanical power is: ； Where, represents the air density, represents the power coefficient of the fan, represents the blade radius, represents wind speed, represents the tip speed ratio, represents the pitch angle of the wind turbine, represents the angular velocity of the wind wheel; Represents the mechanical power input by the fan; The power coefficient of the above fan Substituting the corresponding formula into the mathematical model of mechanical power yields the quadratic function of the fan speed: ； Where, 、 and are the fitting coefficients of mechanical power respectively; The second speed constraint is determined based on the wind turbine mechanical power constraint, the preset active power output drop constraint, the mechanical power at the start of the inertia support phase, and the fitting coefficient of the mechanical power, including: Wind turbine mechanical power constraints: ； Where, For the preset active power output drop constraint, is the mechanical power at the beginning of the inertia support stage, Represents the mechanical power input by the fan; According to the mechanical power constraint of the fan and the quadratic function of the fan speed, the fan speed constraint corresponding to the active output drop constraint is solved, that is, the second speed constraint for: ； The approximate coefficient of mechanical power is determined based on the fan speed at the start of the inertia support phase, the mechanical power at the start of the inertia support phase, the target speed constraint, and the mechanical power of the fan under the target speed constraint, including: ； Where, Indicates the fan speed at the start of the inertia support phase, and are approximate coefficients of mechanical power, The target speed constraint can be solved according to the quadratic function of the fan speed. Corresponding fan mechanical power , that is, the mechanical power of the fan under the target speed constraint.

7. An electronic device, characterized in that: include: one or more processors; a storage device having one or more programs stored thereon; When the one or more programs are executed by the one or more processors, the one or more processors are enabled to implement the method for evaluating the inertia support power limit of a wind turbine as claimed in any one of claims 1 to 5.

8. A storage medium, characterized in that: A computer program is stored thereon, wherein when the computer program is executed by a processor, the method for evaluating the wind turbine inertia support power limit as claimed in any one of claims 1 to 5 is implemented.

Images