Power step control method and device, equipment and storage medium

Abstract

The invention discloses a power step control method, device and equipment and a storage medium, and the method comprises the steps: starting control to provide frequency support for a system when monitoring that a frequency deviation or a frequency change rate exceeds a threshold value, and obtaining a power step through the relation between the rotating speed of a computer side converter and time; the wind energy lost in the process of providing frequency support for the system by the rotor kinetic energy released by the fan is solved, and then the DC voltage reference value is changed through the grid-side converter to release the DC-side capacitor energy storage so as to compensate the lost wind energy. By implementing the method, the frequency supporting capacity of the fan can be fully utilized, and the system frequency stability is improved.

Description

Technical Field

[0001] The present invention relates to the field of electric power technology, and in particular to a power step control method, device, equipment and storage medium. Background Art

[0002] At present, with the widespread access of wind power to the power grid, the inertia level of the system has been greatly reduced, posing a certain threat to the frequency stability of the system. The operating procedures of power grids in various countries require that grid-connected wind turbines can provide a certain amount of inertia and frequency support. In this context, the control strategy of wind turbines participating in system frequency support has received widespread attention. By releasing the kinetic energy of the wind turbine rotor, the wind turbine can provide frequency support for the system under zero standby conditions, taking into account both economic efficiency and frequency support performance.

[0003] At present, permanent magnet synchronous wind turbines have become the mainstream model of new wind power generation. Permanent magnet synchronous wind turbines are connected to the grid through full-size power electronic converters. The DC side capacitors are usually large. By releasing the energy stored in the DC side capacitors, additional inertia response can be provided to the system. However, the existing power step control strategy is designed for doubly fed asynchronous wind turbines, which does not fully utilize the frequency support capability of the DC side capacitors of the converter. Therefore, how to fully coordinate the kinetic energy of the wind turbine rotor and the energy stored in the DC side capacitors of the permanent magnet synchronous wind turbine for frequency support is an urgent problem to be solved. Summary of the invention

[0004] The present invention provides a power step control method, device, equipment and storage medium, which can fully coordinate the kinetic energy of the fan rotor and the DC side capacitor energy storage of the permanent magnet synchronous fan for frequency support to improve the system frequency stability.

[0005] An embodiment of the present invention provides a power step control method, comprising:

[0006] Obtain the basic parameters of the wind turbine, the frequency deviation value at the wind turbine PCC point, and the power reference value of the machine-side converter in real time; wherein the basic parameters include the rated DC voltage, the initial speed of the wind turbine, the inertia of the wind turbine, and the size of the DC side capacitor;

[0007] When the frequency deviation value at the PCC point of the wind turbine is detected to be abnormal, the real-time wind power captured by the generator-side converter is collected;

[0008] Determining a power step amount of a machine-side converter according to the power reference value and the real-time captured wind power;

[0009] Determine the relationship between the speed of the machine-side converter and time according to the power step amount, the initial speed of the wind turbine, the inertia of the wind turbine, and the real-time power support duration;

[0010] Determine the wind energy lost during the support process of the wind turbine according to the relationship between the speed of the machine-side converter and time, the basic parameters and the real-time captured wind power;

[0011] Determine a real-time voltage reference value of a wind turbine grid-side converter according to the lost wind energy, the rated DC voltage and the DC side capacitor;

[0012] Determine the active power injected into the power grid by the wind turbine according to the real-time voltage reference value, the power reference value and the DC side capacitor size;

[0013] According to the active power injected into the grid by the wind turbine, the energy stored in the DC side capacitor is released to compensate for the power loss of the wind turbine.

[0014] Further, specifically:

[0015]

[0016] Where Δf is the frequency deviation at the PCC point; Δf th is the frequency deviation threshold; RoCoF th is the frequency change rate threshold.

[0017] Further, determining the relationship between the speed of the machine-side converter and time according to the power step amount, the initial speed of the wind turbine, the inertia of the wind turbine, and the real-time power support duration includes:

[0018] The relationship between fan speed and time is determined by the following formula:

[0019]

[0020] Among them, ω r0 Indicates the initial speed of the fan; H WT Indicates the fan inertia; t start Indicates the start time of the power support phase; ΔP step is the power step amount; t represents a moment in the power support stage.

[0021] Furthermore, the basic parameters also include: power constant, initial mechanical power of the wind turbine, total duration of the support phase, wind energy utilization coefficient of the wind turbine, maximum wind energy utilization coefficient of the wind turbine, tip speed ratio of the wind turbine, and pitch angle of the wind turbine;

[0022] The determining of the wind energy loss of the wind turbine during the supporting process according to the relationship between the speed of the machine-side converter and time, the basic parameters and the real-time captured wind power includes:

[0023] The lost wind energy is calculated by the following formula:

[0024]

[0025] P ref =P m (t)+ΔP step ,t start <t<t ter ;

[0026] In the formula, C p Indicates the wind energy utilization coefficient of the fan; C pmax represents the maximum wind energy utilization coefficient of the wind turbine; λ represents the tip speed ratio of the wind turbine; β represents the pitch angle of the wind turbine; ω rsw Indicates the speed of the fan when it ends support; T support Indicates the total duration of the support phase; ω r0 is the initial speed of the fan; k g Represents the power constant; P m0 Indicates the initial mechanical power of the fan; ΔP step Indicates the power step amount; P ref Indicates the power reference value; P m (t) represents real-time capture of wind power.

[0027] Further, determining the real-time voltage reference value of the wind turbine grid-side converter according to the lost wind energy, the rated DC voltage and the DC side capacitor size includes:

[0028] The real-time voltage reference value of the wind turbine grid-side converter is calculated by the following formula:

[0029]

[0030] In the formula, V0 represents the rated DC voltage; C represents the DC side capacitance; E loss (t) represents the lost wind energy.

[0031] Further, the determining the active power injected into the power grid by the wind turbine according to the real-time voltage reference value, the power reference value and the DC side capacitor size includes:

[0032] The active power injected into the grid by the wind turbine is calculated by the following formula:

[0033]

[0034] Where P ref Indicates the power reference value; V ref Indicates the real-time voltage reference value; C indicates the DC side capacitance.

[0035] An embodiment of the present invention further provides a power step control device, comprising: a data acquisition module, a real-time wind power acquisition module, a power step amount acquisition module, a speed and time relationship determination module, a lost wind energy determination module, a real-time voltage reference value determination module, an active power determination module, and a DC side capacitor energy storage release module;

[0036] The data acquisition module is used to acquire the basic parameters of the wind turbine, the frequency deviation value at the PCC point of the wind turbine, and the power reference value of the machine-side converter in real time; wherein the basic parameters include the rated DC voltage, the initial speed of the wind turbine, the inertia of the wind turbine, and the size of the DC side capacitor;

[0037] The real-time captured wind power acquisition module is used to collect the real-time captured wind power of the machine-side converter when the frequency deviation value at the PCC point of the wind turbine is detected to be abnormal;

[0038] The power step amount acquisition module is used to determine the power step amount of the machine-side converter according to the power reference value and the real-time captured wind power;

[0039] The speed and time relationship determination module is used to determine the relationship between the speed and time of the machine-side converter according to the power step amount, the initial speed of the wind turbine, the inertia of the wind turbine and the real-time power support duration;

[0040] The lost wind energy determination module is used to determine the lost wind energy of the wind turbine during the support process according to the relationship between the speed and time of the machine-side converter, the basic parameters and the real-time captured wind power;

[0041] The real-time voltage reference value determination module is used to determine the real-time voltage reference value of the wind turbine grid-side converter according to the lost wind energy, the rated DC voltage and the DC side capacitor size;

[0042] The active power determination module is used to determine the active power injected into the power grid by the wind turbine according to the real-time voltage reference value, the power reference value and the DC side capacitor size;

[0043] The DC side capacitor energy storage release module is used to release the DC side capacitor energy storage according to the active power injected into the power grid by the wind turbine to compensate for the power loss of the wind turbine.

[0044] Furthermore, the basis for judging the occurrence of an abnormality is specifically:

[0045]

[0046] Where Δf is the frequency deviation at the PCC point; Δf th is the frequency deviation threshold; RoCoF th is the frequency change rate threshold.

[0047] The present application also provides a terminal device, including:

[0048] one or more processors;

[0049] A memory, coupled to the processor, for storing one or more programs;

[0050] When the one or more programs are executed by the one or more processors, the one or more processors implement the power step control method as described in the above-mentioned embodiment of the invention.

[0051] The present application also provides a computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the power step control method as described in the above-mentioned embodiment of the invention is implemented.

[0052] The following beneficial effects are achieved by implementing the present invention:

[0053] The present invention provides a power step control method, device, equipment and storage medium. When the method detects that the frequency deviation at the PCC point of the wind turbine is abnormal, the method determines the wind energy loss of the wind turbine during the support process through the relationship expression between the speed and time of the machine-side converter, the basic parameters and the real-time captured wind power; thereby determining the real-time voltage reference value of the wind turbine grid-side converter according to the calculated lost wind energy and the rated DC voltage and DC side capacitor size in the basic parameters; then determining the active power injected into the grid by the wind turbine according to the real-time voltage reference value, the power reference value and the DC side capacitor size, and releasing the DC side capacitor energy storage according to the active power injected into the grid by the wind turbine to supplement the power loss of the wind turbine;

[0054] Therefore, through the coordinated work of each wind turbine during the supporting process, the kinetic energy stored in the rotor is released to provide frequency support for the power grid, thereby reducing the amplitude of frequency drop and contributing to the stability of the power grid frequency. Subsequently, the wind energy lost by the wind turbine during the supporting process is calculated so that the DC side capacitor releases the stored electrical energy according to the lost wind energy to compensate for the wind energy lost by the wind turbine during the supporting process due to the reduction in power generation. Compared with the existing control strategy, the control performance of the present application is better. By coordinating the kinetic energy of the wind turbine rotor and the DC side capacitor, it is beneficial to fully utilize the frequency support capability of the wind turbine and improve the frequency stability of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] In order to more clearly illustrate the technical solution of the present application, the drawings required for use in the implementation manner will be briefly introduced below. Obviously, the drawings described below are only some implementation manners of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0056] Figure 1 is a flowchart of a power step control method provided in a certain embodiment of the present application;

[0057] Figure 2 It is a schematic diagram of the control structure topology provided by a certain embodiment of the present application;

[0058] Figure 3 is a topological diagram of a test system provided by a certain embodiment of the present application;

[0059] Figure 4 is a response curve of a test system after a frequency event provided by a certain embodiment of the present application;

[0060] Figure 5 It is the active power curve of the 3# wind turbine after the frequency event provided by a certain embodiment of the present application;

[0061] Figure 6 is a structural schematic diagram of a power step control device provided in a certain embodiment of the present application;

[0062] Figure 7 It is a structural diagram of a terminal device provided in a certain embodiment of the present application. DETAILED DESCRIPTION

[0063] In order to make the purpose, technical solutions and advantages of this application clearer, the technical solutions in this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0064] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0065] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0066] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0067] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0068] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0069] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0070] See also Figure 1 , is a flow chart of a power step control method provided by an embodiment of the present invention, comprising:

[0071] S1. Obtain the basic parameters of the wind turbine, the frequency deviation value at the PCC point of the wind turbine, and the power reference value of the machine-side converter in real time; wherein the basic parameters include the rated DC voltage, the initial speed of the wind turbine, the inertia of the wind turbine, and the size of the DC side capacitor;

[0072] In a preferred embodiment, the basic parameters also include: power constant, initial mechanical power of the wind turbine, total duration of the support phase, wind energy utilization coefficient of the wind turbine, maximum value of the wind energy utilization coefficient of the wind turbine, tip speed ratio of the wind turbine and pitch angle of the wind turbine.

[0073] S2. When the frequency deviation value at the PCC point of the wind turbine is detected to be abnormal, the real-time captured wind power of the generator-side converter is collected;

[0074] In a preferred embodiment, the basis for judging the occurrence of an abnormality is specifically:

[0075]

[0076] Where Δf is the frequency deviation at the PCC point; Δf th is the frequency deviation threshold; RoCoF th is the frequency change rate threshold.

[0077] S3. Determine a power step amount of the machine-side converter according to the power reference value and the real-time captured wind power;

[0078] Specifically, after the power step control is started, the power reference of the generator-side converter can be expressed as:

[0079]

[0080] Among them, P m (t) represents real-time capture of wind power; ΔP step Indicates the power step amount; P ref Indicates the power reference value; t start represents the start time of the power support phase; t represents a certain moment in the power support phase; t ter Indicates the end time of the power support phase; k g represents the power constant; ω represents the speed.

[0081] S4. Determine the relationship between the speed of the machine-side converter and time according to the power step amount, the initial speed of the wind turbine, the inertia of the wind turbine, and the real-time power support duration;

[0082] According to formula (2), the fan rotor motion equation can be written as:

[0083]

[0084] In a preferred embodiment, determining the relationship between the speed of the machine-side converter and time according to the power step amount, the initial speed of the wind turbine, the inertia of the wind turbine, and the real-time power support duration includes:

[0085] The relationship between fan speed and time is determined by the following formula:

[0086]

[0087] Among them, ω r0 Indicates the initial speed of the fan; H WT Indicates the fan inertia; t start Indicates the start time of the power support phase; ΔP step is the power step amount; t represents a certain moment in the power support stage;

[0088] Specifically, by integrating the above formula (3), the relationship between the fan speed and time can be obtained, that is, formula (4).

[0089] S5. Determine the wind energy loss of the wind turbine during the support process according to the relationship between the speed and time of the machine-side converter, the basic parameters and the real-time captured wind power;

[0090] Indicatively, during the frequency support process, the wind turbine speed will deviate from the optimal speed, and the wind power captured in real time will decrease during the support phase, resulting in the loss of captured wind energy. The amount of wind energy lost by the wind turbine is defined as the integral of the reduction in captured wind power over time.

[0091] In a preferred embodiment, the determining of the wind energy loss of the wind turbine during the support process according to the relationship between the speed of the machine-side converter and time, the basic parameters and the real-time captured wind power includes:

[0092] The lost wind energy is calculated by the following formula:

[0093]

[0094]

[0095] In the formula, C p Indicates the wind energy utilization coefficient of the fan; C pmax represents the maximum wind energy utilization coefficient of the wind turbine; λ represents the tip speed ratio of the wind turbine; β represents the pitch angle of the wind turbine; ω rsw Indicates the speed of the fan when it ends support; T support Indicates the total duration of the support phase; ω r0 is the initial speed of the fan; k g Represents the power constant; P m0 Indicates the initial mechanical power of the fan; ΔP step Indicates the power step amount; P ref Indicates the power reference value; P m (t) represents real-time capture of wind power;

[0096] Specifically, according to formula (4), the total duration of the support stage and the speed of the fan when the support ends satisfy the following relationship:

[0097]

[0098] Furthermore, in order to better calculate the lost wind energy, the integral variable is replaced by u, where Based on formula (6), it is transformed into the following formula:

[0099]

[0100] Where λ0 is the initial tip speed ratio and Φ(·) is the original function obtained by integration:

[0101]

[0102] S6. Determine a real-time voltage reference value of the wind turbine grid-side converter according to the lost wind energy, the rated DC voltage and the DC side capacitance;

[0103] Schematically, the voltage reference value of the wind turbine grid-side converter is related to the real-time wind energy loss;

[0104] In a preferred embodiment, determining the real-time voltage reference value of the wind turbine grid-side converter according to the lost wind energy, the rated DC voltage and the DC side capacitor size includes:

[0105] The real-time voltage reference value of the wind turbine grid-side converter is calculated by the following formula:

[0106]

[0107] In the formula, V0 represents the rated DC voltage; C represents the DC side capacitance; E loss (t) represents the lost wind energy;

[0108] Specifically, according to formula (11) and formula (9), formula (11) can be converted into the following formula:

[0109]

[0110] S7, determining the active power injected into the power grid by the wind turbine according to the real-time voltage reference value, the power reference value and the DC side capacitance;

[0111] In a preferred embodiment, determining the active power injected into the power grid by the wind turbine according to the real-time voltage reference value, the power reference value and the DC side capacitor size includes:

[0112] The active power injected into the grid by the wind turbine is calculated by the following formula:

[0113]

[0114] Where P ref Indicates the power reference value; V ref Indicates the real-time voltage reference value; C indicates the DC side capacitance.

[0115] S8. According to the active power injected into the grid by the wind turbine, the energy stored in the DC capacitor is released to compensate for the power loss of the wind turbine;

[0116] Specifically, see Figure 2, which is a schematic diagram of the control structure of the proposed control strategy. When an accident is detected, a start signal is sent to the output timing module. After the control is started, the power reference of the machine-side converter is switched from the maximum power tracking mode to the given output timing, and the DC voltage reference of the grid-side converter is switched from the rated DC voltage to the given DC voltage reference.

[0117] See also Figure 3 , Figure 3 The topology diagram of the test system.

[0118] Figure 3 The test system consists of three equivalent permanent magnet synchronous fans, one synchronous machine, AC bus, local load and variable load. The simulation is implemented based on MATLAB / Simulink.

[0119] See also Figure 4 , is the response curve of the test system after the frequency event. Figure 4 As can be seen from (a), compared with the case where the wind farm does not participate in frequency regulation, the proposed control effectively improves the overall frequency minimum point. Figure 4 (b) is the speed change curve of the three wind turbines. It can be seen that each wind turbine releases the rotor kinetic energy in a coordinated manner during the support process. Figure 4 (c) is the DC voltage variation curve of the 3# wind turbine. It can be seen that the DC side capacitor releases the stored electric energy and compensates for the wind energy lost during the support process of the wind turbine; and the lowest point of the DC voltage does not exceed the limit of the minimum DC voltage.

[0120] See also Figure 5 , Figure 5 This is the active power curve of the 3# wind turbine after the frequency event. Figure 5 As shown in the figure, in the support stage, the actual active power of the machine-side converter tracks its reference value well, that is, the designed wind turbine output curve; in the speed recovery stage, the active power output of the wind turbine is reduced to restore the speed; the active power characteristics of the grid-side converter output are basically consistent with the existing power step control, which verifies the effectiveness of the proposed control strategy.

[0121] See also Figure 6 , is a power step control device provided by a certain embodiment of the present application, comprising: a data acquisition module, a real-time wind power acquisition module, a power step quantity acquisition module, a speed and time relationship determination module, a lost wind energy determination module, a real-time voltage reference value determination module, an active power determination module, and a DC side capacitor energy storage release module;

[0122] The data acquisition module is used to acquire the basic parameters of the wind turbine, the frequency deviation value at the PCC point of the wind turbine, and the power reference value of the machine-side converter in real time; wherein the basic parameters include the rated DC voltage, the initial speed of the wind turbine, the inertia of the wind turbine, and the size of the DC side capacitor;

[0123] The real-time captured wind power acquisition module is used to collect the real-time captured wind power of the machine-side converter when the frequency deviation value at the PCC point of the wind turbine is detected to be abnormal;

[0124] The power step amount acquisition module is used to determine the power step amount of the machine-side converter according to the power reference value and the real-time captured wind power;

[0125] The speed and time relationship determination module is used to determine the relationship between the speed and time of the machine-side converter according to the power step amount, the initial speed of the wind turbine, the inertia of the wind turbine and the real-time power support duration;

[0126] The lost wind energy determination module is used to determine the lost wind energy of the wind turbine during the support process according to the relationship between the speed and time of the machine-side converter, the basic parameters and the real-time captured wind power;

[0127] The real-time voltage reference value determination module is used to determine the real-time voltage reference value of the wind turbine grid-side converter according to the lost wind energy, the rated DC voltage and the DC side capacitor size;

[0128] The active power determination module is used to determine the active power injected into the power grid by the wind turbine according to the real-time voltage reference value, the power reference value and the DC side capacitor size;

[0129] The DC side capacitor energy storage release module is used to release the DC side capacitor energy storage according to the active power injected into the power grid by the wind turbine to compensate for the power loss of the wind turbine.

[0130] In a preferred embodiment, the basis for judging the occurrence of an abnormality is specifically:

[0131]

[0132] Where Δf is the frequency deviation at the PCC point; Δf th is the frequency deviation threshold; RoCoF th is the frequency change rate threshold.

[0133] See also Figure 7 , a certain embodiment of the present application further provides a terminal device, including:

[0134] one or more processors;

[0135] A memory, coupled to the processor, for storing one or more programs;

[0136] When the one or more programs are executed by the one or more processors, the one or more processors implement the power step control method as described above.

[0137] The processor is used to control the overall operation of the terminal device to complete all or part of the steps of the above-mentioned power step control method. The memory is used to store various types of data to support the operation of the terminal device, and these data may include, for example, instructions for any application or method used to operate on the terminal device, and data related to the application. The memory can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (Static Random Access Memory, referred to as SRAM), electrically erasable programmable read-only memory (Electrically Erasable Programmable Read-Only Memory, referred to as EEPROM), erasable programmable read-only memory (Erasable Programmable Read-Only Memory, referred to as EPROM), programmable read-only memory (Programmable Read-Only Memory, referred to as PROM), read-only memory (Read-Only Memory, referred to as ROM), magnetic memory, flash memory, magnetic disk or optical disk.

[0138] In an exemplary embodiment, the terminal device can be implemented by one or more application specific integrated circuits (ASIC), digital signal processors (DSP), digital signal processing devices (DSPD), programmable logic devices (PLD), field programmable gate arrays (FPGA), controllers, microcontrollers, microprocessors or other electronic components to execute the power step control method described in any of the above embodiments and achieve the same technical effect as the above method.

[0139] In another exemplary embodiment, a computer-readable storage medium including a computer program is also provided, and when the computer program is executed by a processor, the steps of the power step control method as described in any of the above embodiments are implemented. For example, the computer-readable storage medium can be the above-mentioned memory including the computer program, and the above-mentioned computer program can be executed by the processor of the terminal device to complete the power step control method as described in any of the above embodiments, and achieve the technical effect consistent with the above method.

[0140] The above is a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several improvements and modifications without departing from the principle of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A power step control method, characterized in that: include: Obtain the basic parameters of the wind turbine, the frequency deviation value at the wind turbine PCC point, and the power reference value of the machine-side converter in real time; wherein the basic parameters include the rated DC voltage, the initial speed of the wind turbine, the inertia of the wind turbine, and the size of the DC side capacitor; When the frequency deviation value at the PCC point of the wind turbine is detected to be abnormal, the real-time wind power captured by the generator-side converter is collected; Determining a power step amount of a machine-side converter according to the power reference value and the real-time captured wind power; Determine the relationship between the speed of the machine-side converter and time according to the power step amount, the initial speed of the wind turbine, the inertia of the wind turbine, and the real-time power support duration; Determine the wind energy lost during the support process of the wind turbine according to the relationship between the speed of the machine-side converter and time, the basic parameters and the real-time captured wind power; Determine a real-time voltage reference value of a wind turbine grid-side converter according to the lost wind energy, the rated DC voltage and the DC side capacitor; Determine the active power injected into the power grid by the wind turbine according to the real-time voltage reference value, the power reference value and the DC side capacitor size; According to the active power injected into the grid by the wind turbine, the energy stored in the DC side capacitor is released to compensate for the power loss of the wind turbine.

2. The power step control method according to claim 1, characterized in that: The basis for judging the occurrence of abnormality is as follows: Where Δf is the frequency deviation at the PCC point; Δf th is the frequency deviation threshold; RoCoF th is the frequency change rate threshold.

3. The power step control method according to claim 1, characterized in that: The determining the relationship between the speed of the machine-side converter and time according to the power step amount, the initial speed of the wind turbine, the inertia of the wind turbine, and the real-time power support duration includes: The relationship between fan speed and time is determined by the following formula: Among them, ω r0 Indicates the initial speed of the fan; H WT Indicates the fan inertia; t start Indicates the start time of the power support phase; ΔP step is the power step amount; t represents a certain moment in the power support stage; t ter Indicates the end time of the power support phase.

4. The power step control method according to claim 3, characterized in that: The basic parameters also include: power constant, initial mechanical power of the wind turbine, total duration of the support phase, wind energy utilization coefficient of the wind turbine, maximum wind energy utilization coefficient of the wind turbine, tip speed ratio of the wind turbine, and pitch angle of the wind turbine; The determining of the wind energy loss of the wind turbine during the supporting process according to the relationship between the speed of the machine-side converter and time, the basic parameters and the real-time captured wind power includes: The lost wind energy is calculated by the following formula: In the formula, C p Indicates the wind energy utilization coefficient of the fan; C pmax represents the maximum wind energy utilization coefficient of the wind turbine; λ represents the tip speed ratio of the wind turbine; β represents the pitch angle of the wind turbine; ω rsw Indicates the speed of the fan when it ends support; T support Indicates the total duration of the support phase; ω r0 is the initial speed of the fan; k g Represents the power constant; P m0 Indicates the initial mechanical power of the fan; ΔP step Indicates the power step amount; P ref Indicates the power reference value; P m (t) represents real-time capture of wind power.

5. The power step control method according to claim 4, characterized in that: The step of determining a real-time voltage reference value of a wind turbine grid-side converter according to the lost wind energy, the rated DC voltage, and the DC side capacitor includes: The real-time voltage reference value of the wind turbine grid-side converter is calculated by the following formula: In the formula, V0 represents the rated DC voltage; C represents the DC side capacitance; E loss (t) represents the lost wind energy.

6. The power step control method according to claim 5, characterized in that: The step of determining the active power injected into the power grid by the wind turbine according to the real-time voltage reference value, the power reference value and the DC side capacitor value comprises: The active power injected into the grid by the wind turbine is calculated by the following formula: Where P ref Indicates the power reference value; V ref Indicates the real-time voltage reference value; C indicates the DC side capacitance.

7. A power step control device, characterized in that: include: Data acquisition module, real-time wind power acquisition module, power step acquisition module, speed and time relationship determination module, lost wind energy determination module, real-time voltage reference value determination module, active power determination module and DC side capacitor energy storage release module; The data acquisition module is used to acquire the basic parameters of the wind turbine, the frequency deviation value at the PCC point of the wind turbine, and the power reference value of the machine-side converter in real time; wherein the basic parameters include the rated DC voltage, the initial speed of the wind turbine, the inertia of the wind turbine, and the size of the DC side capacitor; The real-time captured wind power acquisition module is used to collect the real-time captured wind power of the machine-side converter when the frequency deviation value at the PCC point of the wind turbine is detected to be abnormal; The power step amount acquisition module is used to determine the power step amount of the machine-side converter according to the power reference value and the real-time captured wind power; The speed and time relationship determination module is used to determine the relationship between the speed and time of the machine-side converter according to the power step amount, the initial speed of the wind turbine, the inertia of the wind turbine and the real-time power support duration; The lost wind energy determination module is used to determine the lost wind energy of the wind turbine during the support process according to the relationship between the speed and time of the machine-side converter, the basic parameters and the real-time captured wind power; The real-time voltage reference value determination module is used to determine the real-time voltage reference value of the wind turbine grid-side converter according to the lost wind energy, the rated DC voltage and the DC side capacitor size; The active power determination module is used to determine the active power injected into the power grid by the wind turbine according to the real-time voltage reference value, the power reference value and the DC side capacitor size; The DC side capacitor energy storage release module is used to release the DC side capacitor energy storage according to the active power injected into the power grid by the wind turbine to compensate for the power loss of the wind turbine.

8. The power step control device according to claim 7, characterized in that: The basis for judging the occurrence of abnormality is as follows: Where Δf is the frequency deviation at the PCC point; Δf th is the frequency deviation threshold; RoCoF th is the frequency change rate threshold.

9. A device, characterized in that: include: one or more processors; A memory, coupled to the processor, 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 power step control method as described in any one of claims 1 to 7.

10. A medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the power step control method according to any one of claims 1 to 7 is implemented.

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