A method and system for measuring the inertia and damping parameters of a grid-type wind turbine.

Abstract

This invention discloses a method and system for measuring the inertia and damping parameters of a grid-connected wind turbine, relating to the field of grid-connected converter testing technology. The method includes: connecting a grid-connected wind turbine operating in off-grid mode to a test device; initially applying frequency and small-phase disturbances to the test device; collecting voltage and current data at the turbine ports until the virtual synchronous generator reaches a stable operating state; acquiring the steady-state value of the active power change and the transient response curve of the active power change throughout the entire response process; calculating the damping coefficient based on the steady-state value of the active power change and the applied frequency disturbance according to a first relationship; calculating the envelope of the transient response curve to obtain the product of the natural oscillation angular frequency and the damping ratio; and calculating the virtual inertia based on the reference angular frequency and the damping coefficient according to a second relationship. This invention enables accurate and efficient measurement of inertia and damping parameters.

Description

Technical Field

[0001] This invention relates to the field of grid-connected converter testing technology, and in particular to a method and system for measuring the inertia and damping parameters of grid-connected wind turbines. Background Technology

[0002] With the rapid development of new energy technologies, the penetration rate of new energy power generation, represented by wind power and photovoltaics, is constantly increasing. Faced with the problems of weak active support capability and low system inertia brought about by grid-connected control systems, various grid-forming (GFM) converter control strategies have been proposed domestically and internationally in recent years. Among them, the most typical grid-forming converter control strategy is the virtual synchronous generator (VSG) control strategy. This VSG technology enables the grid-connected converter to simulate the operating characteristics of a synchronous generator, embedding the rotor motion model of the synchronous generator into the control algorithm of the grid-connected converter. This controls the formation of an internal electromotive force with virtual rotor motion characteristics, thereby autonomously constructing voltage and thus possessing the ability to actively support the power grid. Currently, research on VSG mainly focuses on technological applications, neglecting research on measuring the actual external characteristics exhibited by the converter after adopting the VSG control strategy.

[0003] The main parameters of VSG control include the inertia and damping coefficients of the active and reactive power control links. The inertia and damping parameters in the rotor motion equations reflect the inertia and damping characteristics exhibited by the controlled object, which constitute the external characteristics. Currently, research on the virtual inertia and damping coefficients of converters mainly focuses on improving the dynamic and static characteristics of converters, lacking methods for calculating and identifying multiple parameters using voltage and current information under off-grid conditions. However, inertia and damping are crucial parameters for dynamic performance evaluation and stability analysis of microgrids. Therefore, determining the off-grid parameters of virtual inertia (or simply inertia) and damping for VSGs has significant practical implications.

[0004] For new energy power generation systems such as grid-connected wind turbines, existing methods for testing virtual synchronous generator parameters in off-grid environments mainly face the following challenges:

[0005] (1) Currently, the testing methods for grid-connected wind turbines are mostly used. Grid-connected wind turbines rely on detecting the rate of change and amount of change in grid frequency to perform virtual inertia and active power-frequency droop control. During testing, the corresponding performance parameters can be tested by applying an external frequency change signal and observing the active power output response. However, for grid-connected wind turbines, their virtual inertia and droop control response depend on the internal virtual rotor speed. The relationship between external frequency and active power response cannot accurately reflect their performance parameters. Therefore, the grid-connected testing method is not actually suitable for testing grid-connected wind turbines, and the test results obtained using the grid-connected wind turbine testing method are inaccurate.

[0006] (2) Multiple power performance parameters are coupled and affect power characteristics. For example, there are complex interactions between parameters such as frequency, phase, and inertia, which together affect power characteristics. During the test, the influence of multiple parameters needs to be considered at the same time. In addition, under the off-grid test, only the voltage and current of the test equipment port can be obtained, and the signal waveforms of important parameters such as frequency and phase angle cannot be obtained, which makes the test complicated and difficult. Summary of the Invention

[0007] To address the shortcomings of the existing technology, this invention provides a method and system for measuring the inertia and damping parameters of a grid-connected wind turbine. Based on the relationship between the active power of the grid-connected wind turbine and its inertia and damping parameters, a specific testing device is connected to the wind turbine under test. This device applies frequency and phase disturbances to the turbine for testing. During the test, the voltage and current output at the turbine's ports are measured to calculate the active power. The inertia parameter J and damping parameter D of the grid-connected wind turbine under off-grid testing are calculated based on the observed and collected steady-state values ​​and transient response curves of the active power variation. This achieves accurate and efficient measurement of the inertia and damping parameters.

[0008] In a first aspect, the present invention provides a method for measuring the inertia and damping parameters of a grid-type wind turbine.

[0009] A method for determining the inertia and damping parameters of a grid-connected wind turbine generator, comprising:

[0010] To connect the grid-connected wind turbine under test to the test equipment in off-grid mode, the test equipment applies frequency disturbance and small phase disturbance to the test unit at the initial moment, and collects the voltage and current at the unit port until the virtual synchronous generator reaches a stable working state. The steady-state value of the change in active power of the unit and the transient response curve of the change in active power during the entire response process are obtained respectively.

[0011] Based on the steady-state value of the change in active power and combined with the applied frequency disturbance, the damping parameters are calculated according to the first relationship.

[0012] Based on the transient response curve, the envelope of the curve is calculated, and then the product of the natural oscillation angular frequency and the damping ratio is obtained. Then, the inertia parameter is calculated by combining this product value, the reference angular frequency and the calculated damping parameter according to the second relationship.

[0013] Secondly, the present invention provides a system for measuring the inertia and damping parameters of a grid-type wind turbine.

[0014] A system for measuring the inertia and damping parameters of a grid-connected wind turbine includes:

[0015] The data acquisition module is used to connect the test equipment to the grid-connected wind turbine under test operating in off-grid mode. At the initial moment, the test equipment applies frequency disturbance and small phase disturbance to the test unit respectively, and collects the voltage and current at the unit port until the virtual synchronous generator reaches a stable operating state. The steady-state value of the change in active power of the unit and the transient response curve of the change in active power during the entire response process are obtained respectively.

[0016] The damping parameter measurement module is used to calculate the damping parameter based on the steady-state value of the change in active power and the applied frequency disturbance, according to the first relationship.

[0017] The inertia parameter measurement module is used to calculate the envelope of the transient response curve, thereby obtaining the product of the natural oscillation angular frequency and the damping ratio. Then, by combining this product value, the reference angular frequency, and the calculated damping parameter, the inertia parameter is calculated according to the second relationship.

[0018] Thirdly, the present invention also provides an electronic device, including a memory and a processor, and computer instructions stored in the memory and running on the processor, wherein the computer instructions, when executed by the processor, perform the steps of the method described in the first aspect.

[0019] Fourthly, the present invention also provides a computer-readable storage medium for storing computer instructions, which, when executed by a processor, perform the steps of the method described in the first aspect.

[0020] The above one or more technical solutions have the following beneficial effects:

[0021] 1. This invention provides a method and system for measuring the inertia and damping parameters of a grid-connected wind turbine. Based on the relationship between the active power of the grid-connected wind turbine and the inertia and damping parameters, a specific testing device is connected to the grid-connected wind turbine under test. The testing device applies frequency and phase disturbances to the turbine under test. During the test, the voltage and current output at the turbine's port are measured to calculate the active power. The steady-state value and transient response curve of the active power change of the turbine are observed and collected to solve for the inertia parameter J and damping parameter D of the grid-connected wind turbine under off-grid testing, achieving accurate and efficient measurement of the inertia and damping parameters. Compared with the measurement method for grid-connected turbines, the measurement method proposed in this invention only uses the external characteristics exhibited by the turbine without interacting with the control system. The measurement results fully reflect the actual operating results, and the measurement results are more accurate.

[0022] 2. In the method for determining the inertia and damping parameters of the grid-type wind turbine proposed in this invention, the rotor motion equation of the virtual synchronous generator is used as the mathematical model for controlling the virtual synchronous generator. The relationship between the active power of the unit and the inertia and damping parameters is obtained through analysis, and the corresponding parameter determination method is generated accordingly. The inertia parameter J and the damping parameter D can be calculated using this method, and the accuracy of the determination results is further verified by simulation test. Attached Figure Description

[0023] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0024] Figure 1 This is a flowchart of the method for determining the inertia and damping parameters of a grid-type wind turbine according to an embodiment of the present invention;

[0025] Figure 2 A schematic diagram illustrating the rotor operating characteristics of a virtual synchronous generator;

[0026] Figure 3 The equivalent circuit diagram of a grid-connected converter system based on voltage source virtual synchronous generator control is shown below.

[0027] Figure 4 This is a schematic diagram showing the transient response curve reaching its maximum value in an embodiment of the present invention;

[0028] Figure 5 This is a schematic diagram of the frequency perturbation applied during the simulation verification process of an embodiment of the present invention;

[0029] Figure 6 This is a schematic diagram of the active power output curve of the wind turbine during the simulation verification process of an embodiment of the present invention;

[0030] Figure 7This is a schematic diagram showing the calculated values ​​of damping parameters during the simulation verification process of an embodiment of the present invention;

[0031] Figure 8 This is a schematic diagram of the small phase perturbation applied during the simulation verification process of an embodiment of the present invention;

[0032] Figure 9 This is a schematic diagram of the transient response curve and envelope of the active power output of the wind turbine during the simulation verification process of an embodiment of the present invention.

[0033] Figure 10 This is a schematic diagram of the attenuation curve during the simulation verification process of an embodiment of the present invention. Detailed Implementation

[0034] It should be noted that the following detailed descriptions are exemplary and are intended only to describe specific embodiments and to provide further explanation of the invention, and are not intended to limit the scope of exemplary embodiments of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0035] Example 1

[0036] This embodiment provides a method for determining the inertia and damping parameters of a grid-type wind turbine, such as... Figure 1 As shown, it includes the following steps:

[0037] To connect the grid-connected wind turbine under test to the test equipment in off-grid mode, the test equipment applies frequency disturbance and small phase disturbance to the test unit at the initial moment, and collects the voltage and current at the unit port until the virtual synchronous generator reaches a stable working state. The steady-state value of the change in active power of the unit and the transient response curve of the change in active power during the entire response process are obtained respectively.

[0038] Based on the steady-state value of the change in active power and combined with the applied frequency disturbance, the damping parameters are calculated according to the first relationship.

[0039] Based on the transient response curve, the envelope of the curve is calculated, and then the product of the natural oscillation angular frequency and the damping ratio is obtained. Then, the inertia parameter is calculated by combining this product value, the reference angular frequency and the calculated damping parameter according to the second relationship.

[0040] The following content provides a more detailed introduction to the method for determining the inertia and damping parameters of the grid-type wind turbine proposed in this embodiment.

[0041] (1) Modeling the control data model of the virtual synchronous generator

[0042] Virtual synchronous generator control enables grid-connected converters to simulate the output characteristics of traditional synchronous generators, thereby improving system stability. Its control block diagram is shown below. Figure 2 As shown. The method proposed in this embodiment uses the rotor motion equation of a virtual synchronous generator as a basis to mathematically model the VSG control.

[0043] First, the rotor motion equation of the virtual synchronous generator is used as the mathematical model for the control of the virtual synchronous generator, and the rotor motion equation of the virtual synchronous generator is normalized.

[0044] Specifically, the mathematical model for controlling the virtual synchronous generator adopts the rotor motion equation of the virtual synchronous machine, which is:

[0045]

[0046] In the above formula, J and D are the virtual inertial time constants (kg·m). 2 The damping coefficient is the virtual inertial time constant, which is the virtual inertia. ref P e ω represents the input mechanical power and output active power (W) of the virtual synchronous generator, respectively; ω is the rotor angular frequency of the virtual synchronous generator (rad / s); ω0 is the angular frequency of the VSG grid-connected common bus (rad / s), by default ω0 is equal to the reference angular frequency, which can be treated as a constant: ω ref =ω0=2πf0,ω ref The reference value for angular frequency is given by f0, which represents the rated frequency of the power grid. In this embodiment, f0 = 50Hz.

[0047] Next, the above rotor operating equations are normalized, including:

[0048] First, divide both sides by the power reference value S. b (This value is a constant):

[0049]

[0050] Then, normalizing ω, we have the following process:

[0051]

[0052] The per-unit form is as follows:

[0053]

[0054] Meanwhile, if we let the reference value of J be... The baseline value of D is Then we have the following unit-standardized equation:

[0055]

[0056] Furthermore, removing the asterisks to indicate per-unit values, the per-unit formula has the following simplified form:

[0057]

[0058] Where, ω b It refers to the reference value of angular frequency, which is consistent with the parameter ω0, and both are equal to 100π.

[0059] In the above formula, in order to simulate a synchronous generator, parameter P... ref On the control side, there is a power reference value. Unless there is special control, this reference value will not change abruptly. It is treated as a constant within the test time scale.

[0060] Secondly, based on the equivalent circuit diagram of the grid-connected converter system controlled by a voltage source virtual synchronous generator, a virtual impedance is introduced to determine the expression for the active power of the converter. Then, the expression for the active power of the converter is substituted into the rotor motion equation after per-unit processing and linearization is performed.

[0061] Specifically, the equivalent circuit diagram of a grid-connected converter system based on voltage source virtual synchronous generator (VSG) control is as follows: Figure 3 As shown, Z = R + jωL represents the sum of the line impedance and the converter's equivalent impedance. In high-voltage lines, the effect of R can be ignored, and the line impedance is almost inductive. However, in medium- and low-voltage lines, virtual impedance control technology is often introduced to make the line impedance primarily inductive, reducing power coupling caused by line impedance. Based on the above method, the converter's active power P can be obtained. e The expression is:

[0062]

[0063] In the above formula, X represents the equivalent impedance of the converter output; θ E θ U These represent the converter phase angle and the grid phase angle, respectively.

[0064] Substituting it into equation (6), we get:

[0065]

[0066] Linearizing equation (8) yields:

[0067]

[0068] Since the inertia and damping of synchronous generators affect the stability of power systems, the virtual inertia time constant J and the damping coefficient D are the two most critical parameters in the VSG control algorithm. The damping parameter D and the inertia parameter J are measured sequentially in the following manner.

[0069] (2) Determine the damping coefficient D and the virtual inertia time constant J (i.e., the damping parameter D and the inertia parameter J).

[0070] (2.1) For the damping coefficient D, the active power is calculated by measuring the voltage and current at the unit port, and then the power reference value P is subtracted from this active power. ref The change in active power is obtained, and simultaneously, the change in rotor angular frequency of the virtual synchronous generator, i.e., the frequency disturbance Δω, is introduced for solution. The frequency disturbance Δω is:

[0071] ω=ω0+Δω (10)

[0072] Furthermore, based on the rotor motion equations after the per-unit processing described above, a first relationship is determined between the damping coefficient and the changes in rotor angular frequency and active power of the virtual synchronous generator. Based on this, according to the determined first relationship, the damping coefficient can be calculated by measuring the changes in active power and the introduced frequency disturbance (i.e., the change in rotor angular frequency) of the virtual synchronous generator.

[0073] Specifically, the test equipment is used to connect the grid-connected wind turbine under test to the test unit operating in off-grid mode. This test equipment can use a high-capacity, four-quadrant, programmable fast-response three-phase AC power supply. At the initial moment, the test equipment applies a frequency disturbance Δω to the test unit, at which time the active power output of the unit will change accordingly. The current and voltage output of the unit port of the virtual synchronous generator are measured and collected when the virtual synchronous generator reaches a stable operating state, and then the change in active power ΔP of the unit is calculated. e The steady-state value is the change in active power under steady-state conditions.

[0074] Secondly, based on the steady-state value of the active power change and the applied frequency disturbance, the damping coefficient is calculated according to the first relationship. The expression for the first relationship is:

[0075] P e -P ref =D(ω0-ω) (11)

[0076]

[0077] Substituting the frequency disturbance and the steady-state value of the measured change in active power into the expression of the first relationship, the damping coefficient D is calculated. This parameter D can be used as a known parameter for the next step of determining parameter J.

[0078] (2.2) For the virtual inertial time constant J (i.e., inertia parameter J), the product of the natural oscillation angular frequency and the damping ratio is introduced to solve the problem.

[0079] First, based on the formula (9) obtained after linearization, the change in the rotor angular frequency of the virtual synchronous generator Δω and the change in the phase angle of the voltage source Δθ in the formula are used as the basis for the calculation. E Assuming the state variables are used, the state equations, i.e., the transfer function model, are derived. The process is as follows:

[0080]

[0081] The transfer function model is then:

[0082]

[0083] From the above formula, we can obtain the natural oscillation angular frequency ω. n The damping ratio ξ is as follows:

[0084]

[0085]

[0086] Based on the above transfer function model, the second relationship between the inertia parameter and the damping coefficient, reference angular frequency, natural oscillation angular frequency, and damping ratio can be determined as follows:

[0087]

[0088] Based on this, according to the established second relationship, the inertia parameter J can be calculated by measuring the product of the natural oscillation angular frequency and the damping ratio, combined with the reference angular frequency and the calculated damping coefficient.

[0089] Specifically, firstly, the test equipment is connected to the grid-connected wind turbine under test operating in off-grid mode. At the initial moment, a small phase disturbance is applied to the turbine under test using this test equipment. In this embodiment, a disturbance with an angle less than 8° is considered a small phase disturbance. The output power at the turbine port is collected until the virtual synchronous generator reaches a stable operating state, and the transient response curve of the active power change during the entire response process is obtained. In this embodiment, a small phase disturbance Δθ is applied to the test equipment at the initial moment (i.e., time t0). U The phase disturbance needs to be small here to prevent the voltage regulation from having a significant impact, so the internal potential can be considered to remain unchanged. The change in active power ΔP is obtained by measurement. e The transient response curve is a periodic function whose amplitude decays exponentially with time. Furthermore, since the disturbance occurs at time t0, the initially obtained ΔP needs to be...e The transient response curve is shifted to the left by t0 to obtain the transient response curve that oscillates from 0s.

[0090] Secondly, the envelope of the transient response curve is obtained. In this embodiment, the envelope of the curve is obtained by taking the maximum value of the curve, such as... Figure 4 As shown, the expression for this envelope is:

[0091]

[0092] Then take multiple maxima ΔP em Substituting (i) and its corresponding point t(i) into the expression / equation (17) of the envelope, we get:

[0093]

[0094] Solving the system of equations, we obtain the product of the natural oscillation angular frequency and the damping ratio, which is:

[0095]

[0096] In the above solution process, n maximum points are selected and substituted pairwise into the calculation. That is, the n maximum points and their corresponding points are substituted into the envelope expression to calculate the product ω of the natural oscillation angular frequency and the damping ratio. n ξ(i); then average the n-1 product values ​​to obtain the final product ω of the natural oscillation angular frequency and the damping ratio. n ξ.

[0097] Finally, based on the product of the natural oscillation angular frequency and the damping ratio obtained above, and in conjunction with the product value, the reference angular frequency and the calculated damping coefficient, the inertia parameter J is calculated according to the second relationship (i.e., equation (16)).

[0098] Furthermore, the calculated damping coefficient and inertia parameter are all per-unit values, and these per-unit values ​​of the damping coefficient and inertia parameter are respectively compared with the reference values. benchmark value The product of these two values ​​gives the final nominal values ​​of the damping parameter and the nominal value of the inertia parameter.

[0099] To verify the effectiveness of the measurement method proposed in this embodiment, the following simulation example is used for verification and illustration. Specifically, a test equipment model is built using Power Factory software, and parameter calculations are performed in Matlab. The model parameter settings are shown in Table 1 below.

[0100] Table 1 Model Setting Parameters

[0101]

[0102] First, measure the damping coefficient D. For example... Figure 5 As shown, at 1 second, the grid frequency abruptly changes from the rated frequency of 50Hz to 49.2Hz. At this time, the unit's output power increases, and the active power change curve is as follows. Figure 6 As shown. Taking the change in active power of the unit under steady state, the damping coefficient D is solved by equation (12), and the result is as follows. Figure 7 As shown, the per-unit value of the damping coefficient D calculated after steady state is 12.0367, and the nominal value of the damping coefficient D is 0.115MNms / rad. By comparing this calculated value with the set value, the accuracy of the measurement method proposed in this embodiment is further verified.

[0103] Secondly, using the damping coefficient obtained from the above calculation as a known parameter, the virtual inertia coefficient J is determined. For example... Figure 8 As shown, an application is performed on the grid side at 1 second. The phase disturbance, the active power change curve after steady state and its envelope are as follows: Figure 9 As shown, the obtained attenuation curve is as follows: Figure 10 As shown. By substituting the methods proposed in this embodiment into equations (18), (19), and (16), the virtual inertia coefficient J can be solved. The final solution is J = 1.8703 × 10⁻⁶. 2 kg·m 2 , compared to the model setting value of 1.824 × 10 2 kg·m 2 Almost identical.

[0104] Example 2

[0105] This embodiment provides a system for measuring the inertia and damping parameters of a grid-type wind turbine, including:

[0106] The data acquisition module is used to connect the test equipment to the grid-connected wind turbine under test operating in off-grid mode. At the initial moment, the test equipment applies frequency disturbance and small phase disturbance to the test unit respectively, and collects the voltage and current at the unit port until the virtual synchronous generator reaches a stable operating state. The steady-state value of the change in active power of the unit and the transient response curve of the change in active power during the entire response process are obtained respectively.

[0107] The damping parameter measurement module is used to calculate the damping parameter based on the steady-state value of the change in active power and the applied frequency disturbance, according to the first relationship.

[0108] The inertia parameter measurement module is used to calculate the envelope of the transient response curve, thereby obtaining the product of the natural oscillation angular frequency and the damping ratio. Then, by combining this product value, the reference angular frequency, and the calculated damping parameter, the inertia parameter is calculated according to the second relationship.

[0109] Example 3

[0110] This embodiment provides an electronic device, including a memory and a processor, as well as computer instructions stored in the memory and running on the processor. When the computer instructions are executed by the processor, they complete the steps in the method for determining the inertia and damping parameters of a grid-type wind turbine as described above.

[0111] Example 4

[0112] This embodiment also provides a computer-readable storage medium for storing computer instructions, which, when executed by a processor, complete the steps in the method for determining the inertia and damping parameters of a grid-type wind turbine as described above.

[0113] The steps and methods involved in Embodiments 2 to 4 above correspond to those in Embodiment 1. For specific implementation details, please refer to the relevant description section of Embodiment 1. The term "computer-readable storage medium" should be understood as a single medium or multiple media including one or more instruction sets; it should also be understood as including any medium capable of storing, encoding, or carrying an instruction set for execution by a processor and enabling the processor to perform any of the methods in this invention.

[0114] Those skilled in the art will understand that the modules or steps of the present invention described above can be implemented using general-purpose computer devices. Optionally, they can be implemented using computer-executable program code, thereby allowing them to be stored in a storage device for execution by a computer device, or they can be fabricated as separate integrated circuit modules, or multiple modules or steps can be fabricated as a single integrated circuit module. The present invention is not limited to any particular combination of hardware and software.

[0115] The above description is only a preferred embodiment of the present invention. Although the specific implementation of the present invention has been described in conjunction with the accompanying drawings, it is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that, based on the technical solution of the present invention, various modifications or variations that can be made by those skilled in the art without creative effort are still within the scope of protection of the present invention.

Claims

1. A method for determining the inertia and damping parameters of a grid-type wind turbine, characterized in that, include: To connect the grid-connected wind turbine under test to the test equipment in off-grid mode, the test equipment applies frequency disturbance and small phase disturbance to the test unit at the initial moment, and collects the voltage and current at the unit port until the virtual synchronous generator reaches a stable working state. The steady-state value of the change in active power of the unit and the transient response curve of the change in active power during the entire response process are obtained respectively. Based on the steady-state value of the change in active power and combined with the applied frequency disturbance, the damping parameters are calculated according to the first relationship. Based on the transient response curve, the envelope of the curve is calculated, and then the product of the natural oscillation angular frequency and the damping ratio is obtained. Then, the inertia parameter is calculated according to the second relationship by combining the product value, the reference angular frequency and the calculated damping parameter. The expression for the first relation is: ； in, D Indicates the damping coefficient. This represents the frequency disturbance, specifically the change in the rotor angular frequency of the virtual synchronous generator. P ref The mechanical power of the virtual synchronous generator is used as a power reference value. P e The active power of the virtual synchronous generator; The expression for the second relation is: ； in, D Indicates the damping coefficient. J Represents the virtual inertia coefficient. Indicates the natural oscillation angular frequency. Indicates the damping ratio. This indicates the angular frequency of the VSG grid-connected common bus.

2. The method for determining the inertia and damping parameters of a grid-type wind turbine as described in claim 1, characterized in that, Determining the first relationship includes: The rotor motion equation of the virtual synchronous generator is used as the mathematical model for the control of the virtual synchronous generator, and the rotor motion equation of the virtual synchronous generator is normalized. Based on the rotor motion equations after standardization, the first relationship between the damping coefficient and the changes in rotor angular frequency and active power of the virtual synchronous generator is determined; whereby the changes in rotor angular frequency of the virtual synchronous generator are the frequency disturbances.

3. The method for determining the inertia and damping parameters of a grid-type wind turbine as described in claim 1, characterized in that, Determining the second relationship includes: The rotor motion equation of the virtual synchronous generator is used as the mathematical model for the control of the virtual synchronous generator, and the rotor motion equation of the virtual synchronous generator is normalized. Substituting the expression for the active power of the converter into the rotor motion equation after standardization, and after linearization, the state equation set, i.e. the transfer function model, is derived by taking the change in the rotor angular frequency of the virtual synchronous generator and the change in the phase angle of the voltage source in the formula as state variables. Based on the transfer function model, a second relationship is determined between virtual inertia and damping coefficient, reference angular frequency, natural oscillation angular frequency, and damping ratio.

4. The method for determining the inertia and damping parameters of a grid-type wind turbine as described in claim 1, characterized in that, The determination of the inertia parameter includes: Based on the transient response curve, the envelope of the curve is obtained by taking the maximum value; Substituting multiple maxima and their corresponding points into the expression for the envelope, the product of the natural oscillation angular frequency and the damping ratio is obtained; where, n Substituting the maxima and their corresponding points into the envelope expression, we can calculate and obtain... n -1 is the product of the natural oscillation angular frequency and the damping ratio; for n -1 product values ​​are averaged to obtain the final product of the natural oscillation angular frequency and the damping ratio; The virtual inertia is calculated based on the product of the natural oscillation angular frequency and the damping ratio, combined with the reference angular frequency and the calculated damping coefficient.

5. The method for determining the inertia and damping parameters of a grid-type wind turbine as described in claim 1, characterized in that, The calculated damping coefficient and virtual inertia are both per-unit values. The product of the per-unit value of the damping coefficient and the per-unit value of the virtual inertia with the corresponding reference value is the final nominal value of the damping coefficient and the nominal value of the virtual inertia.

6. A system for measuring the inertia and damping parameters of a grid-type wind turbine, characterized in that, include: The data acquisition module is used to connect the test equipment to the grid-connected wind turbine under test operating in off-grid mode. At the initial moment, the test equipment applies frequency disturbance and small phase disturbance to the test unit respectively, and collects the voltage and current at the unit port until the virtual synchronous generator reaches a stable operating state. The steady-state value of the change in active power of the unit and the transient response curve of the change in active power during the entire response process are obtained respectively. The damping parameter measurement module is used to calculate the damping parameter based on the steady-state value of the change in active power and the applied frequency disturbance, according to the first relationship. The inertia parameter measurement module is used to calculate the envelope of the transient response curve, thereby obtaining the product of the natural oscillation angular frequency and the damping ratio. Then, by combining the product value, the reference angular frequency, and the calculated damping parameter, the inertia parameter is calculated according to the second relationship. The expression for the first relation is: ； in, D Indicates the damping coefficient. This represents the frequency disturbance, specifically the change in the rotor angular frequency of the virtual synchronous generator. P ref The mechanical power of the virtual synchronous generator is used as a power reference value. P e The active power of the virtual synchronous generator; The expression for the second relation is: ； in, D Indicates the damping coefficient. J Represents the virtual inertia coefficient. Indicates the natural oscillation angular frequency. Indicates the damping ratio. This indicates the angular frequency of the VSG grid-connected common bus.

7. An electronic device, characterized in that, It includes a memory and a processor, as well as computer instructions stored in the memory and running on the processor. When the processor executes the computer instructions, it completes the steps of the method for determining the inertia and damping parameters of a grid-type wind turbine as described in any one of claims 1-5.

8. A computer-readable storage medium, characterized in that, Used to store computer instructions, which, when executed by a processor, complete the steps of a method for determining the inertia and damping parameters of a grid-type wind turbine as described in any one of claims 1-5.

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