Voltage source doubly fed wind turbine transient stability analysis method and device, electronic equipment

Abstract

The present invention discloses a method and device for transient stability analysis of a voltage source doubly fed wind turbine, and electronic equipment, comprising: constructing a priority current limiter expression and stator voltage and stator current expressions of a voltage source doubly fed wind turbine using the priority current limiter, wherein the voltage source doubly fed wind turbine is connected to a remote AC power grid via a power grid inductance; calculating, according to the priority current limiter expression, two power angle sets for causing the system to enter a fault current limiting state and restore to a normal operating state; calculating, according to the priority current limiter expression and the stator voltage and stator current expressions of the voltage source doubly fed wind turbine, the output active power of the voltage source doubly fed wind turbine in the fault current limiting state; and determining, according to the two power angle sets and the output active power, the influence of different saturation current angles on the transient stability of the voltage source doubly fed wind turbine.

Description

Technical Field

[0001] The present application relates to the technical field of grid-connected control of doubly-fed wind turbines, and in particular to a transient stability analysis method and device for a voltage source doubly-fed wind turbine, and electronic equipment. Background Art

[0002] With the gradual increase in the penetration rate of new energy, the global wind power installed capacity has increased significantly, which requires wind turbines to adopt voltage source control strategies to support grid voltage and frequency.

[0003] Because voltage-source doubly-fed wind turbines exhibit voltage-source characteristics, selecting an appropriate overcurrent protection strategy to protect the rotor-side converter during large disturbances is crucial. Given that the current controllers of voltage-source devices often achieve fast command tracking, the application of a current limiter can effectively limit rotor overcurrent in voltage-source doubly-fed wind turbines. Among various current limiters, priority current limiters offer the advantage of flexible adjustment of the d-axis current ratio during fault conditions, leading to their widespread application.

[0004] Since the priority current limiter is always triggered during the grid fault, it is worth further analyzing whether the system can resume normal operation and ensure transient stability after the grid fault is cleared. To this end, relevant scholars have conducted the following research: ① The literature [Huang L, Xin H, Wang Z, Zhang L, Wu K and Hu J, Transient Stability Analysis and Control Design of Droop-Controlled Voltage Source Converters Considering Current Limitation [J]. IEEE Transactions on Smart Grid, 2019, 10(1): 578-591.] reveals the transient instability mechanism of a voltage source converter with a d-axis priority current limiter after the grid fault is cleared. ② The literature [Rokrok E, Qoria T, Bruyere A, Francois B and Guillaud X, Transient Stability Assessment and Enhancement of Grid-Forming Converters Embedding Current Reference Saturation as Current Limiting Strategy[J]. IEEE Transactions on Power Systems, 2022, 37(2): 1519-1531.] designed the optimal saturation current angle to increase the critical fault clearing time of the voltage source converter. ③ The literature [Fan B and Wang X, Fault Recovery Analysis of Grid-Forming Inverters with Priority-Based Current Limiters[J]. IEEE Transactions on Power Systems, 2023, 38(6): 5102-5112.] explained the influence of short-circuit ratio and current limiter parameters on the fault recovery process of the voltage source converter. It can be seen that the above research is mainly carried out on the voltage source converter, and the characteristics of the power controller are mainly considered when establishing the system transient model.

[0005] However, when studying voltage-source doubly-fed (VSFD) wind turbines, the presence of an asynchronous motor as the intermediate link between the control target (stator-side voltage source function) and the implementation method (rotor voltage output by the rotor converter) necessitates additional consideration of the dynamic response of the voltage controller during transient stability analysis. This characteristic is fundamentally different from that of a VSC. Therefore, directly applying existing VSC research to VSFD wind turbines can lead to inaccurate transient stability analysis and a failure to reflect the unit's true operating conditions. Summary of the Invention

[0006] In view of this, embodiments of the present application provide a method and device for analyzing transient stability of a voltage source doubly fed wind turbine, and an electronic device.

[0007] According to a first aspect of an embodiment of the present application, a method for transient stability analysis of a voltage source doubly fed wind turbine is provided, comprising:

[0008] Constructing a priority current limiter expression and stator voltage and stator current expressions of a voltage source doubly fed wind turbine using the priority current limiter, wherein the voltage source doubly fed wind turbine is connected to a remote AC grid via a grid inductor;

[0009] According to the priority current limiter expression, two power angle sets are calculated to respectively cause the system to enter a fault current limiting state and restore to a normal operating state;

[0010] Calculating the output active power of the voltage source doubly fed wind turbine in a fault current limiting state according to the priority current limiter expression and the stator voltage and stator current expressions of the voltage source doubly fed wind turbine;

[0011] According to the two power angle sets and the output active power, the influence of different saturation current angles on the transient stability of the voltage source doubly fed wind turbine is determined.

[0012] According to a second aspect of an embodiment of the present application, a voltage source doubly fed wind turbine transient stability analysis device is provided, comprising:

[0013] A construction module is used to construct an expression for a priority current limiter and an expression for a stator voltage and a stator current of a voltage source doubly fed wind turbine using the priority current limiter, wherein the voltage source doubly fed wind turbine is connected to a remote AC power grid via a grid inductor;

[0014] A first calculation module is used to calculate two power angle sets for causing the system to enter a fault current limiting state and restore a normal operating state respectively according to the priority current limiter expression;

[0015] A second calculation module is used to calculate the output active power of the voltage source doubly fed wind turbine in a fault current limiting state according to the priority current limiter expression and the stator voltage and stator current expressions of the voltage source doubly fed wind turbine;

[0016] The analysis module is used to determine the influence of different saturation current angles on the transient stability of the voltage source doubly fed wind turbine according to the two power angle sets and the output active power.

[0017] According to a third aspect of an embodiment of the present application, there is provided an electronic device, including:

[0018] one or more processors;

[0019] a memory for storing one or more programs;

[0020] When the one or more programs are executed by the one or more processors, the one or more processors implement the method as described in the first aspect.

[0021] According to a third aspect of an embodiment of the present application, a computer-readable storage medium is provided, on which computer instructions are stored. When the instructions are executed by a processor, the steps of the method described in the first aspect are implemented.

[0022] The technical solutions provided by the embodiments of the present application may have the following beneficial effects:

[0023] This application calculates two sets considering the dynamic coupling of the voltage controller and the priority current limiter, overcoming the lack of research on the transient stability of voltage source doubly fed wind turbines in related technologies, which leads to the problem of being unable to provide guidance for the design of key control parameters. It then achieves the effect of quantitatively analyzing the impact of different saturation current angles on the transient stability of voltage source doubly fed wind turbines, and guides the selection of current limiting parameters to improve system robustness.

[0024] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0026] Figure 1 The present invention is a flow chart showing a method for transient stability analysis of a voltage source doubly fed wind turbine according to an exemplary embodiment.

[0027] Figure 2 The topology of a voltage source doubly fed wind turbine is shown according to an exemplary embodiment.

[0028] Figure 3 The figure shows the transient stability analysis results of the system under different saturation current angle selections according to an exemplary embodiment.

[0029] Figure 4 is a simulation waveform shown according to an exemplary embodiment.

[0030] Figure 5 The present invention is a block diagram of a device for analyzing transient stability of a voltage source doubly fed wind turbine according to an exemplary embodiment. DETAILED DESCRIPTION

[0031] Exemplary embodiments will be described in detail herein, with examples illustrated in the accompanying drawings. In the following description, when referring to the drawings, identical numerals in different figures represent identical or similar elements, unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all embodiments consistent with the present application. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present application, as detailed in the appended claims.

[0032] The terms used in this application are for the purpose of describing specific embodiments only and are not intended to limit this application. As used in this application and the appended claims, the singular forms "a," "an," "the," and "the" are intended to include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the term "and / or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.

[0033] It should be understood that although the terms first, second, third, etc. may be used in this application to describe various information, such information should not be limited to these terms. These terms are only used to distinguish information of the same type from each other. For example, without departing from the scope of this application, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Depending on the context, the word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining".

[0034] Figure 1 FIG. 1 is a flow chart showing a method for transient stability analysis of a voltage source doubly fed wind turbine according to an exemplary embodiment. Figure 1 As shown, the method may include the following steps:

[0035] S1: Constructing a priority current limiter expression and stator voltage and stator current expressions of a voltage source doubly fed wind turbine using the priority current limiter, wherein the voltage source doubly fed wind turbine is connected to a remote AC grid via a grid inductor;

[0036] Specifically, the priority current limiter can flexibly adjust the ratio of the dq axis rotor current of the voltage source doubly fed wind turbine during a fault, and has the advantage of supporting the grid voltage / frequency. Its expression is as follows:

[0037] ;

[0038] in: Output reference current phasor for voltage controller, Output reference current phasor for priority current limiter, I max is the maximum allowable current amplitude on the rotor side of the doubly fed wind turbine, is the saturation current angle of the priority current limiter, j is a unit imaginary number.

[0039] The stator voltage equation and grid impedance voltage drop expression of the voltage source doubly fed wind turbine are as follows:

[0040] ;

[0041] in: u sdq is the stator voltage of the doubly fed wind turbine, j is a unit imaginary number, ω 1 is the rated angular frequency, L s is the stator inductance of the doubly fed wind turbine, i sdq is the stator current of the doubly fed wind turbine, L m is the excitation inductance of the doubly fed wind turbine, i rdq is the doubly fed wind turbine rotor current, V g is the grid voltage amplitude, δ is the power angle, L g is the grid inductance.

[0042] According to the above expressions, the stator voltage and stator current expressions of the voltage source doubly fed wind turbine can be obtained as follows:

[0043] ;

[0044] in: u sdq is the stator voltage of the doubly fed wind turbine, L s is the stator inductance of the doubly fed wind turbine, V g is the grid voltage amplitude, δ is the power angle, j is a unit imaginary number, ω 1 is the rated angular frequency, L g is the grid inductance, L m is the excitation inductance of the doubly fed wind turbine, i rdq is the doubly fed wind turbine rotor current,i sdq is the stator current of the doubly fed wind turbine.

[0045] The expressions of the stator voltage and stator current of the doubly fed wind turbine are functions of the rotor current and will be used many times in the following analysis and calculation.

[0046] S2: Calculate two power angle sets that cause the system to enter a fault current limiting state and restore to a normal operating state, respectively, according to the priority current limiter expression;

[0047] Specifically, since the voltage source doubly fed wind turbine realizes the stator side voltage source function through the rotor side converter, it is necessary to consider the dynamic characteristics of its voltage controller to reflect the control effect of the rotor current on the stator voltage. Figure 2 As shown in Figure 2, the voltage controller expression of the voltage source doubly fed wind turbine is:

[0048]

[0049] in: Output reference current phasor for voltage controller, E is the internal voltage phasor, ω 1 is the rated angular frequency, j is a unit imaginary number, Z v = R v + jω 1 L v is the virtual impedance, R v and L v are virtual resistance and virtual inductance respectively, i sdq is the stator current of the doubly fed wind turbine, k pv is the proportional coefficient of the voltage controller of the doubly fed wind turbine, u sdq is the stator voltage of the doubly fed wind turbine, L s is the stator inductance of the doubly fed wind turbine, L m is the excitation inductance of the doubly fed wind turbine.

[0050] When the system is in normal operation, the stator voltage and stator current expressions of the voltage source doubly fed wind turbine are substituted into the voltage controller expression to obtain the power angle set that causes the voltage source doubly fed wind turbine to enter the fault current limiting state as follows:

[0051]

[0052] in: δis the power angle, Ω1 represents the power angle set for switching from normal operation to fault current limiting state, and the set S represents the unit circle, δ́ is the power angle within the unit circle, ω 1 is the rated angular frequency, L g is the grid inductance, L s is the stator inductance of the doubly fed wind turbine, E is the internal voltage phasor, j is a unit imaginary number, Z v = R v + jω 1 L v is the virtual impedance, R v and L v are virtual resistance and virtual inductance respectively, V g is the grid voltage amplitude, L m is the excitation inductance of the doubly fed wind turbine, I max is the maximum allowable current amplitude on the rotor side of the doubly fed wind turbine.

[0053] When the system is in the fault current limiting state, the expression of the priority current limiter triggering period is substituted into the voltage controller expression of the voltage source doubly fed wind turbine, and the power angle set that enables the voltage source doubly fed wind turbine to return to normal operation can be obtained as follows:

[0054]

[0055]

[0056] in: δ is the power angle, Ω2 represents the power angle set for switching from the fault current limiting state to the normal operating state, and the set S represents the unit circle, δ́ is the power angle within the unit circle, E is the internal voltage phasor, k pv is the proportional coefficient of the voltage controller of the doubly fed wind turbine, L s is the stator inductance of the doubly fed wind turbine, V g is the grid voltage amplitude, j is a unit imaginary number, ω 1 is the rated angular frequency, L g is the grid inductance, Lm is the excitation inductance of the doubly fed wind turbine, I max is the maximum allowable current amplitude on the rotor side of the doubly fed wind turbine, is the saturation current angle of the priority current limiter, Z v = R v + jω 1 L v is the virtual impedance, R v and L v are virtual resistance and virtual inductance respectively. Figure 3 The yellow area represents δ Ω2 and δ Ω1 is established, the pink area represents δ Ω2 and δ Ω1 holds.

[0057] S3: Calculating the output active power of the voltage source doubly fed wind turbine in a fault current limiting state according to the priority current limiter expression and the stator voltage and stator current expressions of the voltage source doubly fed wind turbine;

[0058] Specifically, according to the stator voltage and stator current expressions of the voltage source doubly fed wind turbine, the output active power of the voltage source doubly fed wind turbine is calculated as follows:

[0059]

[0060] in: P The output active power of the voltage source doubly fed wind turbine is: L m is the excitation inductance of the doubly fed wind turbine, V g is the grid voltage amplitude, i rdq is the doubly fed wind turbine rotor current, δ is the power angle, L g is the grid inductance, L s is the stator inductance of the doubly fed wind turbine.

[0061] According to the priority current limiter expression, the output active power of the voltage source doubly fed wind turbine in the fault current limiting state is calculated as follows:

[0062]

[0063] in:P limit is the output active power of the voltage source doubly fed wind turbine under fault current limiting state, L m is the excitation inductance of the doubly fed wind turbine, V g is the grid voltage amplitude, I max is the maximum allowable current amplitude on the rotor side of the doubly fed wind turbine, is the saturation current angle of the priority current limiter, δ is the power angle, L g is the grid inductance, L s is the stator inductance of the doubly fed wind turbine.

[0064] According to the output active power expression of the voltage source doubly fed wind turbine under the fault current limiting state, the stable equilibrium point and unstable equilibrium point of the system under different saturation current angle selection can be obtained, as shown in the figure below: Figure 3 Shown as red and blue lines in (a).

[0065] S4: determining the influence of different saturation current angles on the transient stability of the voltage source doubly fed wind turbine according to the two power angle sets and the output active power of the voltage source doubly fed wind turbine in the fault current limiting state;

[0066] Specifically, Figure 3 In (a), the purple star-shaped vertical axis represents the saturation current angle of the selected priority current limiter, and the horizontal axis represents the position of the corresponding power angle at the moment the grid fault is cleared. The green solid line with an arrow represents the direction of movement of the power angle after the fault is cleared.

[0067] like Figure 3 As shown in Case 1, after the grid fault is cleared, δ Ω2 and δ If Ω1 is established, the system exits the fault current limiting state, corresponding to Figure 4 The simulation results shown in (a) are as follows;

[0068] like Figure 3 As shown in Case 2, after the grid fault is cleared, δ Ω2 and δ If Ω1 holds true, the system will experience high-frequency oscillation, corresponding to Figure 4 The simulation results shown in (b) are as follows;

[0069] like Figure 3 As shown in Case 3, after the grid fault is cleared, δWhen the system reaches the stable equilibrium point under the fault current limiting state, the system is locked in the fault current limiting state, corresponding to Figure 4 The simulation results are shown in (c).

[0070] It can be seen from the above embodiments that the present application achieves the effect of quantitatively analyzing the impact of different saturation current angles on the transient stability of the voltage source doubly fed wind turbine by calculating two sets considering the dynamic coupling of the voltage controller and the priority current limiter, thereby guiding the selection of current limiting parameters to improve the robustness of the system.

[0071] Corresponding to the aforementioned embodiment of the method for analyzing transient stability of a voltage source doubly fed wind turbine, the present application also provides an embodiment of a device for analyzing transient stability of a voltage source doubly fed wind turbine.

[0072] Figure 5 This is a block diagram of a voltage source doubly fed wind turbine transient stability analysis device according to an exemplary embodiment. Figure 5 , the device comprises:

[0073] Construction module 1 is used to construct a priority current limiter expression and a stator voltage and stator current expression of a voltage source doubly fed wind turbine using the priority current limiter, wherein the voltage source doubly fed wind turbine is connected to a remote AC power grid via a grid inductor;

[0074] A first calculation module 2 is used to calculate two power angle sets for causing the system to enter a fault current limiting state and restore a normal operating state according to the priority current limiter expression;

[0075] A second calculation module 3 is used to calculate the output active power of the voltage source doubly fed wind turbine in a fault current limiting state according to the priority current limiter expression and the stator voltage and stator current expressions of the voltage source doubly fed wind turbine;

[0076] The analysis module 4 is configured to determine the influence of different saturation current angles on the transient stability of the voltage source doubly fed wind turbine according to the two power angle sets and the output active power.

[0077] Regarding the apparatus in the above embodiment, the specific manner in which each module performs operations has been described in detail in the embodiment of the method, and will not be elaborated here.

[0078] For the device embodiments, since they basically correspond to the method embodiments, the relevant parts can be referred to the partial description of the method embodiments. The device embodiments described above are merely schematic, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the present application scheme. A person of ordinary skill in the art can understand and implement it without paying any creative work.

[0079] Accordingly, the present application also provides an electronic device, comprising: one or more processors; a memory for storing one or more programs; when the one or more programs are executed by the one or more processors, the one or more processors implement the transient stability analysis method of the voltage source doubly fed wind turbine as described above.

[0080] Accordingly, the present application also provides a computer-readable storage medium having computer instructions stored thereon, which, when executed by a processor, implement the above-mentioned method for transient stability analysis of a voltage source doubly-fed wind turbine.

[0081] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the contents disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present application that follow the general principles of the present application and include common knowledge or customary techniques in the art not disclosed herein. The description and examples are to be considered merely as exemplary, and the true scope and spirit of the present application are indicated by the claims.

[0082] It should be understood that the present application is not limited to the exact structures described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. A transient stability analysis method for a voltage source doubly fed wind turbine, characterized in that: include: Constructing a priority current limiter expression and stator voltage and stator current expressions of a voltage source doubly fed wind turbine using the priority current limiter, wherein the voltage source doubly fed wind turbine is connected to a remote AC grid via a grid inductor; According to the priority current limiter expression, two power angle sets are calculated to respectively cause the system to enter a fault current limiting state and restore to a normal operating state; Calculating the output active power of the voltage source doubly fed wind turbine in a fault current limiting state according to the priority current limiter expression and the stator voltage and stator current expressions of the voltage source doubly fed wind turbine; Determining the effects of different saturation current angles on the transient stability of a voltage source doubly fed wind turbine based on the two power angle sets and the output active power; The priority current limiter expression is as follows: ； in: Output reference current phasor for voltage controller, Output reference current phasor for priority current limiter, I max is the maximum allowable current amplitude on the rotor side of the doubly fed wind turbine, φ is the saturation current angle of the priority current limiter, j is a unit imaginary number; The stator voltage and stator current of the voltage source doubly fed wind turbine are expressed as follows: ； in: u sdq is the stator voltage of the doubly fed wind turbine, L s is the stator inductance of the doubly fed wind turbine, V g is the grid voltage amplitude, δ is the power angle, ω 1 is the rated angular frequency, L g is the grid inductance, L m is the excitation inductance of the doubly fed wind turbine, i rdq is the doubly fed wind turbine rotor current, i sdq is the stator current of the doubly fed wind turbine, j is a unit imaginary number; Among them, the power angle set that causes the voltage source doubly fed wind turbine to enter the fault current limiting state is as follows: in: δ is the power angle, Ω1 represents the power angle set for switching from normal operation to fault current limiting state, and the set S represents the unit circle, δ́ is the power angle within the unit circle, ω 1 is the rated angular frequency, L g is the grid inductance, L s is the stator inductance of the doubly fed wind turbine, E is the internal voltage phasor, j is a unit imaginary number, Z v = R v + jω 1 L v is the virtual impedance, R v and L v are virtual resistance and virtual inductance respectively, V g is the grid voltage amplitude, L m is the excitation inductance of the doubly fed wind turbine; Among them, the power angle set that enables the voltage source doubly fed wind turbine to return to normal operation is as follows: in: δ is the power angle, Ω2 represents the power angle set for switching from the fault current limiting state to the normal operating state, and the set S represents the unit circle, δ́ is the power angle within the unit circle, E is the internal voltage phasor, k pv is the proportional coefficient of the voltage controller of the doubly fed wind turbine, L s is the stator inductance of the doubly fed wind turbine, V g is the grid voltage amplitude, j is a unit imaginary number, ω 1 is the rated angular frequency, L g is the grid inductance, L m is the excitation inductance of the doubly fed wind turbine, I max is the maximum allowable current amplitude on the rotor side of the doubly fed wind turbine, φ is the saturation current angle of the priority current limiter, Z v = R v + jω 1 L v is the virtual impedance, R v and L v are virtual resistance and virtual inductance respectively.

2. The method according to claim 1, characterized in that The output active power is as follows: in: P limit is the output active power of the voltage source doubly fed wind turbine under fault current limiting state.

3. The method according to claim 2, characterized in that According to the two power angle sets and the output active power, the influence of different saturation current angles on the transient stability of the voltage source doubly fed wind turbine is determined, including: When the grid fault is cleared, δ Ω2 and δ If Ω1 holds, the system exits the fault current limiting state; When the grid fault is cleared, δ Ω2 and δ If Ω1 holds, the system will experience high-frequency oscillations; When the grid fault is cleared, δ When the system reaches the stable equilibrium point under the fault current limiting state, the system is locked in the fault current limiting state.

4. A voltage source doubly fed wind turbine transient stability analysis device, characterized in that: include: A construction module is used to construct an expression for a priority current limiter and an expression for a stator voltage and a stator current of a voltage source doubly fed wind turbine using the priority current limiter, wherein the voltage source doubly fed wind turbine is connected to a remote AC power grid via a grid inductor; A first calculation module is used to calculate two power angle sets for causing the system to enter a fault current limiting state and restore a normal operating state respectively according to the priority current limiter expression; A second calculation module is used to calculate the output active power of the voltage source doubly fed wind turbine in a fault current limiting state according to the priority current limiter expression and the stator voltage and stator current expressions of the voltage source doubly fed wind turbine; An analysis module, configured to determine the effects of different saturation current angles on the transient stability of the voltage source doubly fed wind turbine according to the two power angle sets and the output active power; The priority current limiter expression is as follows: ； in: Output reference current phasor for voltage controller, Output reference current phasor for priority current limiter, I max is the maximum allowable current amplitude on the rotor side of the doubly fed wind turbine, φ is the saturation current angle of the priority current limiter, j is a unit imaginary number; The stator voltage and stator current of the voltage source doubly fed wind turbine are expressed as follows: ； in: u sdq is the stator voltage of the doubly fed wind turbine, L s is the stator inductance of the doubly fed wind turbine, V g is the grid voltage amplitude, δ is the power angle, ω 1 is the rated angular frequency, L g is the grid inductance, L m is the excitation inductance of the doubly fed wind turbine, i rdq is the doubly fed wind turbine rotor current, i sdq is the stator current of the doubly fed wind turbine, j is a unit imaginary number; Among them, the power angle set that causes the voltage source doubly fed wind turbine to enter the fault current limiting state is as follows: in: δ is the power angle, Ω1 represents the power angle set for switching from normal operation to fault current limiting state, and the set S represents the unit circle, δ́ is the power angle within the unit circle, ω 1 is the rated angular frequency, L g is the grid inductance, L s is the stator inductance of the doubly fed wind turbine, E is the internal voltage phasor, j is a unit imaginary number, Z v = R v + jω 1 L v is the virtual impedance, R v and L v are virtual resistance and virtual inductance respectively, V g is the grid voltage amplitude, L m is the excitation inductance of the doubly fed wind turbine; Among them, the power angle set that enables the voltage source doubly fed wind turbine to return to normal operation is as follows: in: δ is the power angle, Ω2 represents the power angle set for switching from the fault current limiting state to the normal operating state, and the set S represents the unit circle, δ́ is the power angle within the unit circle, E is the internal voltage phasor, k pv is the proportional coefficient of the voltage controller of the doubly fed wind turbine, L s is the stator inductance of the doubly fed wind turbine, V g is the grid voltage amplitude, j is a unit imaginary number, ω 1 is the rated angular frequency, L g is the grid inductance, L m is the excitation inductance of the doubly fed wind turbine, I max is the maximum allowable current amplitude on the rotor side of the doubly fed wind turbine, φ is the saturation current angle of the priority current limiter, Z v = R v + jω 1 L v is the virtual impedance, R v and L v are virtual resistance and virtual inductance respectively.

5. An electronic device, characterized in that: include: one or more processors; a memory for storing one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors implement the method according to any one of claims 1 to 3.

6. A computer-readable storage medium having computer instructions stored thereon, characterized in that: When the instruction is executed by a processor, the steps of the method according to any one of claims 1 to 3 are implemented.

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